# Maha MH-C9000 SUPPORT / FAQ - continuation



## willchueh

I would like to start this thread to answer user questions about the MH-C9000. The 2nd post contains a FAQ which shall be amended from the time to time. 

For features and general pre-sales questions/discussion, please use this thread:
https://www.candlepowerforums.com/threads/140144

William


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## willchueh

*Re: Maha MH-C9000 SUPPORT Thread*

*MH-C9000 Frequently Asked Questions
*
Updated Jan. 5, 2007

*Using the BREAK-IN mode, I am seeing a charging capacity much higher than the capacity I programmed. Why is the battery overcharged? 
*
When using the BREAK-IN mode, the charger puts in 1.6 times the capacity of the battery (entered at the start of the charge). This does not cause any harm to the battery as the charging rate is very low (only 10% of the battery capacity). The increased total charging capacity compensates for energy lost as heat. This is the charging scheme recommended by International Electrotechnical Commission (IEC). 



*I am charging some older batteries and see that the charging capacity is much higher than the capacity I programmed. Why doesn't the charger terminate correctly? 
*
The charger terminates by voltage and by temperature simultaneously. For certain older (and low quality) batteries, they do not produce the proper negative delta V signal (a small voltage drop at the conclusion of the charge) needed for the charger to stop. At the same time, the battery temperature failed to reach the termination limit as the charging rate was probably too low.

To address this issue, you should attempt to perform a BREAK-IN mode on the batteries first. You should also use a higher charging rate. 



*When using higher charging current, the charging capacity seems to reduce. Is this normal? 
*
When charging at higher current, the charge completeness reduces thereby lowering the charging capacity. This is to prevent battery overheating. This typically occurs at a rate greater than 1500mA. Generally speaking, 1000mA achieves nearly full charge completeness for AA batteries. 

Even after the charge ends (DONE appears on screen), the charger will apply a topoff charge and continuous maintenance charge. Despite that the capacity on the screen no longer increases, the batteries are being topped off. 

If you would like to achieve better charge completeness at higher currents, a small fan can be added to cool the batteries externally. 



*Why is it not recommended to charge battery below 0.33C? 
*
When charging below 0.33C (except in BREAK-IN) mode, the batteries may not produce a sufficient end-of-charge signal for the charger to terminate correctly. Although the temperature sensors will safeguard battery overheating, lower charging rate might not cause enough heating in the batteries to trip the sensors. 

If low charging rate is desired, you should use the BREAK-IN mode. Charging in that mode is terminated by only time (1.6 times battery capacity) and temperature. 



*After the charge begins, why do I see an abnormally high voltage (~ 1.6V to 2.0V) on the screen? 
*
In the first few seconds, the MH-C9000 performs a proprietary "high impedance" check to filter out batteries unsafe to charge including non-rechargeable batteries. During this time, a high current is applied and voltage measured to determine the impedance of the battery. 

The voltage will return to normal by the second time voltage data is displayed on the screen. 



*Why doesn't the charging and discharging current reach the set values exactly? I thought the charger is supposed to be precise. 
*
The charging and discharging current are pulsed, thereby causing the displayed current to go up and down. The capacity calculation is based on the actual current rather than the set current so capacity calculation remains accurate. 



*I am using the CHARGE mode. Why is the capacity different than my battery capacity? 
*
The capacity displayed in any charging process is called the "charging capacity." This is the amount of energy put into the batteries. This number does not equal to the battery's capacity as it is dependent on the amount of charge already in the battery as well as the battery's internal resistance. 

For example, a half used 2000mAh battery may only show a charging capacity of 1000mAh since the battery is half full. 

It is normal for the charging capacity to exceed battery capacity by as much as 30% depending on battery brand and charging rate. 

To determine the battery's useful capacity, you must look at the "discharge capacity." Such information is available in the REFRESH & ANALYZE, BREAK-IN, DISCHARGE, and CYCLE modes. Note that the battery is not recharged in the DISCHARGE mode. 



*How do I tell if the capacity displayed on the screen is charging or discharging capacity?
*
If charging or discharging is in-progress, a blackbox contain either CHARGE or DISCHG will be displayed on the screen. The capacity shown during charging is always the charging capacity. Similarly, the capacity shown during discharging is the discharging capacity. 

In the CHARGE mode, the final capacity displayed (after DONE appears) is the charging capacity.

In the REFRESH & ANALYZE and BREAK-IN mode, the final capacity displayed is the discharging capacity. The battery have also been recharged after the discharge. 

In the DISCHARGE mode, the final capacity displayed is also the discharging capacity. However, the battery is not recharged. 

In the CYLCE mode, the capacities saved in memory always refer to the discharging capacity.



*When I discharge certain batteries, the current seem to taper off near the end of the discharge and seems to take very long to finish. Why and does this affect the capacity of the battery?*

This is normal for batteries that exhibt high internal resistsance. MH-C9000 measures the voltage of the batteries while briefly pausing the discharge (every few seconds). For high resistance battery, this voltage might differ from the actual voltage of the battery. For the MH-C9000, it is not designed to maintain set current when battery is below 0.9V. 

This does not affect the calculated capacity as the realtime current is used in the capacity integration. 



*Using the CYCLE mode, why do I see a "0 mAh" capacity on the screen? What happened to the saved battery capacity? 
*
A CYCLE is consisted of:
Charge > 1 Hour Rest > Discharge > 1 Hour Rest (repeats for programmed number of times) 
The discharge capacity is saved into the memory at completion of discharge but cannot be reviewed until that cycle is completed (after the 1 hour rest). During the rest, a zero capacity is displayed.

During this period, all previously completed cycle data can be viewed, but not the most recent cycle. It will become available after that particular cycle is completed. 

Cycle data can be accessed anytime after completion of the first cycle by using the "UP" and "DOWN" keys. 



*There is an arrow that moves below the slot number. What does it mean? *

The LCD screen displays information a slot at a time. The information (capacity, current, time, voltage) is displayed twice before moving on to the next slot. The arrow points to the slot reporting. 



*Is it normal for the batteries to get warm during charging?
*
Yes, batteries do get warm during the charge due to both internal heat and heat produced by the charger. Lower charging rate can yield lower battery temperature, but it is not recommended to go below 0.33C or 0.33 times the battery capacity. 

Adding an external fan can also cool the battery. 



*The manual makes recommendations for charging rates. How about discharging rate*

Most NiMH batteries can accept discharge rate up to 3 times its capacity. A higher discharge rate will yield lower capacity. 

For accurate capacity measurement, use the BREAK-IN mode which complies with IEC standards (0.2C discharge rate). 



*Is the MH-C9000 compatible with the new "low self-discharge" batteries (e.g. Sanyo Eneloop)? *

Yes. Follow the same charging rate recommendations for general NiMH batteries. 



*What is the maximum capacity supported by the MH-C9000?
*
The maximum capacity supported is 20,000mAh making it compatible with future technologies. 



*The charger cannot detect my battery. What can be done? 
*
Virtually all batteries can be detected by the charger. Therefore, if a battery cannot be detected, it is likely not making good contact with the charger. This can be caused by improper seating of the battery or battery not meeting the IEC dimension standard. Try rotating the battery or placing it in another slot.



*There is a faint noise emanating from the charger. Is this normal? 
*
The charger can produce some high frequency hum, which is generated by the high frequency pulse charging and switchers.


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## Black Rose

I read a good portion of part 1 of this thread and it seems like all the big issues have been resolved with this charger.

The only thing that has me questioning getting one vs a BC-900 is the rather random clicking and squeeling. For the ones that do this, how loud is it?

My current charger is completely silent unless you put your head right next to it, then you can hear slight clicking.


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## Mr Happy

It makes a quiet whistling noise that pulses once a second. How much it bothers you might depend on the sample and how acute your hearing is. Other chargers I have make a similar noise -- most likely caused by switched mode regulator circuitry.

To my ears I can only hear it in a quiet room if I am close to the charger. For a teenager with really sharp hearing it might sound much louder. It doesn't bother me at all though; it gives me a comforting feeling that the charger is working.


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## Codeman

When I first got mine, I could hear it if the TV was off or on low and I was within 2-3 feet. It's become background noise to me, so I don't even notice it anymore. If it was me looking to buy, I wouldn't let this be a reason to not get the C9000.


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## Black Rose

Thanks for the feedback guys. Just ordered one.

I'll use it in my computer room instead of the hallway outside our bedroom like I do with the other charger. If nothing else, it will amuse the cats for a bit


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## Black Rose

Got my MH-C9000 yesterday, version 0G0KA.

Let the charging (and discharging) begin


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## Black Rose

I'm now running a second set of ROV NiMh AA cells through a Refresh Analyze cycle and my cells are in pretty bad shape.

Out of the first batch of ROV NiMh AA cells, two of them are showing 1/4 of their capacity, one cell in the second batch has finished and it also is showing 1/4 of it's capacity.

These cells were originally charged in a timed charger (22 hours) and later charged in a smart charger. I stopped using the timed charger when I got the smart charger.

Looks like I'm going to be running the Break-in cycle on all my batteries.
With the amount of batteries I need to put through the break-in cycle, I think I should have bought a second C9000.


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## Black Rose

Yesterday I was running a Refresh Analyze cycle on my second batch of 2000 mAh ROV batteries. 

One of the ones that is having issues showed a charge rate of 3950 ma  and was very hot to the touch. 

The FAQ says that the rate can be "much" higher but that seemed to be a bit excessive. I took the battery out and let if cool down.

I then put it back in to do a discharge on it before I run a Break-in cycle to see if I can bring the battery back to life.

Given that this particular battery is only has about 500 mAh capacity at the moment, was the 3950 ma normal? Another one of the cells in this bunch also has low capacity but showed the normal charge rate.

BTW, I was using 1000 ma charge and 500 ma discharge settings.


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## Mr Happy

Black Rose said:


> Yesterday I was running a Refresh Analyze cycle on my second batch of 2000 mAh ROV batteries.
> 
> One of the ones that is having issues showed a charge rate of 3950 ma  and was very hot to the touch.
> 
> The FAQ says that the rate can be "much" higher but that seemed to be a bit excessive. I took the battery out and let if cool down.
> 
> I then put it back in to do a discharge on it before I run a Break-in cycle to see if I can bring the battery back to life.
> 
> Given that this particular battery is only has about 500 mAh capacity at the moment, was the 3950 ma normal? Another one of the cells in this bunch also has low capacity but showed the normal charge rate.
> 
> BTW, I was using 1000 ma charge and 500 ma discharge settings.


The one that reached 3950 and got hot must have missed the normal charge termination. Considering you were using a 1000 mA charge rate, it must be a fairly sick cell to have done that. It neither generated a -dV signal, nor exceeded 1.47 V.

Although it takes ages, it is probably a good idea to run a break-in cycle on old and badly performing cells as the very first step before trying a normal refresh on them. If the break-in shows a lower than expected capacity, run another break-in and see if it improves by 10% or more. If it does, keep doing break-ins. If it doesn't, you are better to put it in the recycle bin and replace it.


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## TorchBoy

Black Rose said:


> One of the ones that is having issues showed a charge rate of 3950 ma  and was very hot to the touch.


A charge *rate* of just under 4 amps? (3950 mA, note capitalisation). I've never seen an MH-C9000 vary by that much on charge - even on discharge 1183 mA is the highest I've seen.

Do you mean it had been charged 3950 *mAh*?


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## Black Rose

TorchBoy said:


> Do you mean it had been charged 3950 *mAh*?


That's likely what it was.


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## Black Rose

I have some 750 mAh AAA cells that I want to run through the Break In cycle.

The C9000 doesn't allow 50 mAh steps in break in mode, so do I enter 800 mAh as the capacity and slightly overcharge them, or set 700 mAh as the capacity and under charge them?


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## Mr Happy

I'd go with 700. The actual capacity may come in under 750 anyway.

The break-in mode is always going to "overcharge" the cells. Even at 700 mAh, it will apply a charge of 1.6 x 700 = 1120 mAh.


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## TorchBoy

While you probably want more than a largely cynical answer, if 750 mAh is a typical capacity exaggeration then 700 mAh is probably closer to what they really are. But the 16 hour Break In will fill them anyway.


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## Black Rose

I have a question regarding the accuracy of the Capacity reported by the C9000 after a break in cycle has completed.

I just took the second set of 4 non-LSD Rayovac AA 2100 mAh NiMh cells off the C9000, and they too have lost a significant portion of their capacity.

The kicker with these cells is that I have had them for just over 6 months and they appear to be crap already. They were previously charged using a Rayovac charger and were used in Wii controllers. Compared to my other non-LSD cells, these ones were used properly (with the exception of the questionable Rayovac smart charger)

The 8 cells capacity as reported by the C9000 range from a low of 1240 mAh to a high of 1409 mAh.

The reason I am asking about the accuracy is that I am going to contact Rayovac about these particular cells since they are relatively new and were charged in a Rayovac branded charger designed for NiMh cells.

I've already replaced them with Eneloop and ROV Hybrids, but am ticked that they went bad so fast. They only cost $14 for the 8 cells, but still shouldn't have crapped out this soon.

*EDIT 3/31/2008: I contacted Rayovac about these cells and was told that these cells (NM715-40P with green/chrome/black battery labels) are 1400 mAh cells. If true, that would explain what I thought was a serious capacity loss. *

*However, the information provided from Rayovac does not match the data sheet posted on their technical site around the time these particular batteries showed up in the retail channels.*


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## TorchBoy

Black Rose, you could try putting them through a few cycles on the C9000, and see if they improve at all.


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## Eugene

I noticed that my rayovac cells test at a much lower than rated capacity compared to sanyo cells. I have sanyo's that are 7-9 years old that are down up to 80% capacity and 4 year old rayovacs that are down to 75% capacity.


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## Mr Happy

Black Rose said:


> I have a question regarding the accuracy of the Capacity reported by the C9000 after a break in cycle has completed.


The accuracy in general is quite good. In case you have any doubts about your particular sample of the C9000, you can check it by putting a set of Eneloops through a break-in cycle. You should find with those a reported capacity in the 1900 to 1950 mAh range.

It's not unheard of for some cells to be significantly down on their capacity though. I have a set of XG 2400 mAh that came with a charger, hardly even used, and they won't read higher than about 1600 mAh on a break-in cycle.


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## Black Rose

TorchBoy said:


> Black Rose, you could try putting them through a few cycles on the C9000, and see if they improve at all.


I think I'll put the crappy ROVs on my MH-C800S and run some conditioning cycles on them. The conditioning cycle on the C800S only takes about 16 hours vs the 45+ with the C9000.

I still have 24 Eneloops and 16 ROV Hybrids to break in yet, so I don't want to tie up the C9000 for these questionable cells right now.



Mr Happy said:


> The accuracy in general is quite good. In case you have any doubts about your particular sample of the C9000, you can check it by putting a set of Eneloops through a break-in cycle. You should find with those a reported capacity in the 1900 to 1950 mAh range.


I've got a few Eneloops to break in , so I'll use that as a benchmark since they are the cream of the crop of LSDs and seem to have very reliable capacities.


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## Mr Happy

Black Rose said:


> I still have 24 Eneloops and 16 ROV Hybrids to break in yet


There is no conclusive evidence that Eneloops need or benefit from a break-in charge mind, so there's no need to process all those cells through any cycles. Just get them out of the package and start using them


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## Black Rose

Mr Happy said:


> There is no conclusive evidence that Eneloops need or benefit from a break-in charge mind, so there's no need to process all those cells through any cycles. Just get them out of the package and start using them


I read something about that the other night in an older thread from sometime last year. 

I was going to ask that question again to see what the latest info was on that subject, to see if I needed to do the break in on those cells or not. 

I'll just use some, then charge them up and then check the capacity.


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## Bones

Mr Happy said:


> There is no conclusive evidence that Eneloops need or benefit from a break-in charge mind, so there's no need to process all those cells through any cycles. Just get them out of the package and start using them



Although you are absolutely correct insofar as the conclusive evidence is concerned, I have made it a habit to run 3 back-to-back forming charges on my Eneloops before putting them into service.

Considering that almost all the Eneloops sold in North America seem to have been made around the middle of 2006, it just seems like a reasonable precaution.

I consider it equivilant to a good stretch in the morning, only in the case of the Eneloop, the night has lasted close to two years now in some instances.

Notwithstanding the apparent stability of the Enleoop during storage, it just seems inevitable to me that some separation and/or settling of the chemicals has to have taken place.

While the forming charge may be less important for lower drain devices, it would seem almost critical for those devices that require a high drain.

As I understand it, if there is chemical separation and/or settling, then hot spots could form in the dryer areas at higher drain rates, causing permanent damage to the cell.

Besides, what possible harm can it do, especially with an alleged 1000 cycles to play with?



SilverFox said:


> ...
> The "forming" charge refers to a slow charge that is designed to equalize the electrolyte within the cell, and it also balances the cells within a battery pack. It also allows the separator to "soak up" the electrolyte so it can function to its maximum extent.


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## Mr Happy

Bones said:


> Besides, what possible harm can it do, especially with an alleged 1000 cycles to play with?


Those are good points. Nothing is lost by paying careful attention to how you prepare and use your cells, and it can only ensure you get the best out of them. I will think about that next time I break open a pack of Eneloops.


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## 45/70

I just thought I'd throw in a little C-9000/eneloop info here. I recently received 20 AA eneloops dated 8/06. I initially discharged them with the C-9000 @ 100mA rate. All were 1400+ mAh. I then ran the break in mode, but stopped it after the first charge. I then ran a refresh/analyze @ 1000mA charge, 500mA discharge. The cells checked out at 1939-2010mAh. The average was about 1970mAh. I realize this was only one 0.1C charge, however it would seem to indicate that the forming had little effect. Just the same, I'd probably do it that way again, as has been mentioned, it can't hurt. 

Dave


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## Codeman

Mr Happy said:


> There is no conclusive evidence that Eneloops need or benefit from a break-in charge mind, so there's no need to process all those cells through any cycles. Just get them out of the package and start using them



While a break-in technically shouldn't be needed with new and *fresh* cells, my 19 month test showed that they do need periodic maintenance. If someone buys some "new" Eneloops that were manufactured a year or more prior to purchase, they will need some help to get up to full capacity. All that's left to decide are the semantics of what to call such a charge.:shrug:


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## Mr Happy

Hi Codeman,

I just took another look at your 19 month test post, and I have to say your results are exactly in line with the normally expected performance for Eneloops. A normal charge with top-off on the C9000 will give discharge capacities in the 1850-1900 range, while a break-in charge will give capacities in the 1900-1950 range, sometimes up to 1980. A break-in charge is a fuller charge than a regular charge.

So it seems to me that your 19 month old cells were performing to spec right out of the package.

Of course, as discussed above, a refresh cycle or two might be a good idea anyway just to ensure the cells are in top condition.


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## Eugene

I thought eneloop were supposed to be a min of 2000mAh?


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## Mr Happy

Eneloops are nominally 2000 mAh, minimum 1900 mAh.

Here is the Sanyo data sheet: http://www.eneloop.info/uploads/media/Datasheet_-_HR-3UTG_01.pdf

According to the way industry measures and quotes nominal capacity, the full nominal capacity is not typically available in normal usage.

Also to reinforce what Bones said above, the linked Sanyo data sheet says the internal resistance of Eneloops will reach a typical low value of 25 milliohms after going through two to three break-in cycles from new.


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## Turak

Mr Happy said:


> There is no conclusive evidence that Eneloops need or benefit from a break-in charge mind, so there's no need to process all those cells through any cycles. Just get them out of the package and start using them


 
I would have to disagree with you regarding the Break-In cycles. I did a bit of testing on the Eneloops and found that they DID benefit from 1 or 2 Break-In cycles when new.

The test was actually trying to determine whether the new Eneloops did better with a few Refresh/Analyze cycles or a couple Break-In cycles when new.

The results.....the Eneloops, even though new, did benefit from both the R/A cycles and from the Break-In cycles, with the Break-In cycles coming out just slightly ahead.

Go read the following thread...

https://www.candlepowerforums.com/threads/175350


Batt# - Initial Capacity - BreakIn Cycle 1 - BreakIn Cycle 2
-----------------------------------------------------------
EL5 - 1478 mA - 2068 mA - 2150 mA
EL6 - 1477 mA - 2064 mA - 2141 mA
EL7 - 1468 mA - 2057 mA - 2141 mA
EL8 - 1488 mA - 2074 mA - 2169 mA

Generally speaking, the 'new' Eneloops have been sitting on the shelf for a year or two. General recommendations say to run a Break-In cycle on any battery that has been sitting idle for 3 months or more.

I think that the single test above shows that the batteries DID indeed benefit from 2 Break-In cycles, bringing them back up to their 'maximum' capacities. Not to mention helping to fully activate all the reactive materials in the battery.

I would say that, in general, if you want to try to maximize the life of your batteries. Run a Break-In cycle or two before ever using them. Then Run a R/A cycle every 10-15 cycles. Run a Break-In cycle every 25 or so.

Yes, you can just go ahead and start using them right out of the pack, although as the battery manufacturers state, "It may take a few charge/discharge cycles before the batteries reach their maximum performance".

For the low current draw devices, this is probably not too important. The high current draw devices, however, I think this becomes more of a factor for overall battery capacity/longevity.


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## Turak

Mr Happy said:


> There is no conclusive evidence that Eneloops need or benefit from a break-in charge mind, so there's no need to process all those cells through any cycles. Just get them out of the package and start using them


 
I would have to disagree with you regarding the Break-In cycles. I did a bit of testing on the Eneloops and found that they DID benefit from 1 or 2 Break-In cycles when new.

The test was actually trying to determine whether the new Eneloops did better with a few Refresh/Analyze cycles or a couple Break-In cycles when new.

The results.....the Eneloops, even though new, did benefit from both the R/A cycles and from the Break-In cycles, with the Break-In cycles coming out just slightly ahead.

Go read the following thread...

https://www.candlepowerforums.com/threads/175350


Batt# - Initial Capacity - BreakIn Cycle 1 - BreakIn Cycle 2
-----------------------------------------------------------
EL5 - 1478 mA - 2068 mA - 2150 mA
EL6 - 1477 mA - 2064 mA - 2141 mA
EL7 - 1468 mA - 2057 mA - 2141 mA
EL8 - 1488 mA - 2074 mA - 2169 mA

Generally speaking, the 'new' Eneloops have been sitting on the shelf for a year or two. General recommendations say to run a Break-In cycle on any battery that has been sitting idle for 3 months or more.

I think that the single test above shows that the batteries DID indeed benefit from 2 Break-In cycles, bringing them back up to their 'maximum' capacities. Not to mention helping to fully activate all the reactive materials in the battery.

I would say that, in general, if you want to try to maximize the life of your batteries. Run a Break-In cycle or two before ever using them. Then Run a R/A cycle every 10-15 cycles. Run a Break-In cycle every 25 or so.

Yes, you can just go ahead and start using them right out of the pack, although as the battery manufacturers state, "It may take a few charge/discharge cycles before the batteries reach their maximum performance".

For the low current draw devices, this is probably not too important. The high current draw devices, however, I think this becomes more of a factor for overall battery capacity/longevity.


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## Mr Happy

Turak said:


> I would have to disagree with you regarding the Break-In cycles. I did a bit of testing on the Eneloops and found that they DID benefit from 1 or 2 Break-In cycles when new.


No problem, I have revised my opinion on this -- see posts above.

For average users I'd say Eneloops don't _need_ breaking in, but for best performance they certainly can benefit from breaking in.

Incidentally, I'm puzzled by your ~2150 mAh capacity measurements. Have you measured numbers that high with other samples than just those four? They are higher numbers than I have measured myself or seen reported elsewhere.


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## Turak

I have checked the capacities on well over 30 'new' (2006) Eneloops so far...

I generally am getting between 2050 to 2150 out of all of them....when new and after at least 2 Break-In cycles.

I beleive it is because my MH-C9000 is a slightly older revision 0G0B01. It seems that the newer units are more conservative on their calculations. They are DEFINITELY more conservative on how fully they charge a cell now (basically they don't). Well....I should say, not as full as the earlier units did. Maha backed off because some cells were getting too hot when charging them at the 1A rate.

I definitely agree as far as the 'average' users. Its the power users and the maximize the life (cycles) that are going to see the most benefit from the extra care...


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## Rzr800

Turak said:


> "...I beleive it is because my MH-C9000 is a slightly older revision 0G0B01. It seems that the newer units are more conservative on their calculations. They are DEFINITELY more conservative on how fully they charge a cell now (basically they don't). Well....I should say, not as full as the earlier units did.."


 
This has to be the dumbest question of the month...yet is this why we witness the average "two hour" extra charging time in many member's posts...and is this advice centered around the newer chargers? (thanks in advance; I have an OGOE01).


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## Bones

Rzr800 said:


> This has to be the dumbest question of the month...



Sorry, but their actually valid questions all, Rzr800.



Rzr800 said:


> yet is this why we witness the average "two hour" extra charging time in many member's posts...



Yes.



Rzr800 said:


> and is this advice centered around the newer chargers?



Again, yes.



Rzr800 said:


> (thanks in advance; I have an OGOE01).



Your welcome, and the OGOE01 does qualify as a 'newer' charger.


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## Rzr800

You're a good man, my friend; as are the many others who have taken the time to educate us on this machine and batteries in general. I never fully realized previously how or if an investment such as this would benefit; yet having it together now with this site's guidance has made a big difference in something actually significant in our family's budget.


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## Mr Happy

Regarding the charging of Eneloops on the C9000, it's illuminating to look at Sanyo's data sheet for AA Eneloops that I linked to above: http://www.eneloop.info/uploads/media/Datasheet_-_HR-3UTG_01.pdf

If you look at the bottom of this document at the typical charge/discharge curves, this is what is shown:

Fast charge is recommended at 1C, 2000 mA, with termination at minus delta-V = -10 mV. At 25°C, the peak voltage prior to termination is above 1.6 V. With this charge, discharge at 400 mA with termination at 1.0 V will give a measured capacity a little less than 2000 mAh.

Now the later model C9000 chargers will stop charging when the cell voltage reaches 1.47 V, so they will never reach the 1.6 V minus delta-V point. This explains why you get "low" charge capacities of Eneloops on the C9000. On the other hand, the cells don't have a chance to get warm, so it is actually being kind to the cells this way.


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## TorchBoy

Mr Happy said:


> Incidentally, I'm puzzled by your ~2150 mAh capacity measurements.


I have seen Eneloop AA capacities as high as 2116 mAh, and a handful 2100 mAh or higher.



Bones said:


> Your welcome, and the OGOE01 does qualify as a 'newer' charger.


I believe 0G0E01 (zeros, not Os) was the first batch of the third firmware version.


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## chewy78

Well I have the ogoka version and i just finished a break in of my ''duraloop cells. They were 1968,1921,1955,and 1978. I did a 400ma discharge after that and I still got 1974,1926,1959, and 1986 respectively. Isn't that on the low side?


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## Bones

TorchBoy said:


> ...
> I believe 0G0E01 (zeros, not Os) was the first batch of the third firmware version.



Good to know Torchboy, and good news for Rzr800.

And you're correct in the format, which I must make it a point to remember.

Otherwise, searching for pertinent information on the MH-C9000 updates becomes a much more difficult endeavour.


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## Mr Happy

chewy78 said:


> Well I have the ogoka version and i just finished a break in of my ''duraloop cells. They were 1968,1921,1955,and 1978. I did a 400ma discharge after that and I still got 1974,1926,1959, and 1986 respectively. Isn't that on the low side?


It lines up exactly with the numbers I measure on my cells. 

Note that your second discharge gave slightly higher readings. If you have the patience you could do another one or two break-in cycles to see if they increase any more.


----------



## chewy78

I could break them in again, then my other cells will get jealous of them. but first I have to break in the other duralooops and energizer 2100's I have, so I have a base line to go on. This charger is kinda neat.


----------



## Doug.S

This is a new item but under this generic title topic....

I bought a C9000 about a year ago. Last Dec. slot 1 died....it got stuck trying to ALWAYS charge (as shown in the display) even with no batts in it....and would not reset after being unplugged for days....tho the start-up display seemed normal.

So nicely and responsibly it was replaced by mfr under warranty as being defective. That was just fine.

But now the replacement unit is doing the same thing...so I wrote but not heard back as yet.

My question is: others experiencing this same problem? is it a frequent problem? is there anyway to prevent such occurrence? 

I am a low usage user... 2 to 4 AA batts charged per week and do not do anything unusual with batts or charger.

Doug.S


----------



## TorchBoy

Hi Doug. It sounds like a problem I had, where the charger would think there was a cell in slot 2, then restart instead of charging it, and hence just endlessly restarted/rebooted. There have been a few others with the same problem.

What batch number does your present one have? It's on the label on the back, something like 0G0B01.


----------



## TorchBoy

Before I forget it, the manual that came with my latest MH-C9000 (0H0AA) still has the minimum recommended charge rate of 0.3C.


----------



## SilverFox

Hello Ian,

Yes, I don't believe the manual was included in the improvement...

Tom


----------



## TorchBoy

Tom, in the Cycle mode when it pauses for two (!) hours after charging, is it doing a top up charge? You don't mention it in your comparison.


----------



## Mr Happy

TorchBoy said:


> in the Cycle mode when it pauses for two (!) hours after charging, is it doing a top up charge?


I don't know the answer to this, but there is a way to determine what it is doing.

You can use an Eneloop for testing and watch it after the charge completes. The normal charge will finish when the cell reaches 1.47 V, and the voltage will then drop back down a bit, say to 1.45 V. Now if a top off charge is being applied the voltage will slowly creep back up again to 1.48 V or 1.49 V over the next two hours. However, if no top off charge is being applied, the voltage will stabilize at 1.45 V or even drop down to about 1.43 V.


----------



## TorchBoy

Yes, I think it did increase, which is why I first thought it was charging. Then I noticed that it took 2 hours, not the 1 hour the Break In rest takes. I'll run another test to confirm.


----------



## SilverFox

Hello Ian,

I believe we looked at that, but I can't find the information.

For some reason I think it does a trickle charge during the two hours between charging and discharging, bit I don't know that for sure.

Tom


----------



## Doug.S

TorchBoy said:


> Hi Doug. It sounds like a problem I had, where the charger would think there was a cell in slot 2, then restart instead of charging it, and hence just endlessly restarted/rebooted. There have been a few others with the same problem.
> 
> What batch number does your present one have? It's on the label on the back, something like 0G0B01.


 

0G0IA


----------



## Doug.S

TorchBoy said:


> Hi Doug. It sounds like a problem I had, where the charger would think there was a cell in slot 2, then restart instead of charging it, and hence just endlessly restarted/rebooted. There have been a few others with the same problem.
> 
> What batch number does your present one have? It's on the label on the back, something like 0G0B01.


 
0G0IA

Maha is sending another replacement and will test this failed unit I'll return to them.


----------



## junglemike

Hi. I am new Maha c9000 user. I have couple of questions, hope you can help me.

Question #1)
Suppose I perform a Refresh&Analyze function on some specific battery, choose charge current 700ma, discharge 400ma. When operation is done, capacity is (in my particular case 1320)
Than I do a charge mode of the same cell @ 700ma, than let it rest 20-30 min (not 2 hours as it rests in refresh mode) And then i perform a discharge operation @ 400ma, Result capacity is 1190 - somewhat less.
And the same pattern repeats itself with many cells, not just one.
Can anybody explain this?

Question #2). I have some very old dead cells, that i'm trying to revive.
They apparently have high internal resistance. Once i charge them (with slow current) and try to perform a discharge operation @ 800ma - I get DONE after less than 1 min, and capacity is 0mah (maybe 1-2mah)
Now, when i set a discharge current to be 100-200ma, it discharges it for a long time and reaches >1000mah. But more interestingly, voltage stays very low all the time <1v (0.94, 0.95v etc...) 
I've read that it terminates the discharge process when cell reaches 1v. So how is tis possible? And what to do with these old cells to try to revive them?


----------



## SilverFox

Hello Junglemike,

When you perform a discharge 20 minutes after Done is displayed, you are cutting out the top off charge. The C9000 applies a 100 mA top off charge for 2 hours after Done is displayed. If you add a little less than 200 mAh, due to charging inefficiencies, to your results, you should be close to what you saw on the Refresh/Analyze mode.

Crap cells should be recycled. If you want to play, you can do 12 cycles of Refresh/Analyze using 500 mA charging at 100 mA discharging. At the end of this, do a 1000 mA charge, wait 2 hours to complete the top off, then do a 500 mA discharge. This will give you an idea of how well your efforts paid off.

Now that you have run your experiment, recycle the cells if they have not returned to at least 80% of their labeled capacity. 

Tom


----------



## Glock40

I have a quick question that I felt did not warrant starting a new thread. Just bought a pack of 4 Duracells 2650mAh. I am wanting to do a break in on these using the C-9000. When i am prompted to enter the capacity i have to choose either 2600 or 2700. Should i go hi and select 2700 or stay safe and select 2600.


----------



## Black Rose

Go with 2600.

I asked a similar question with regards to some 750 mAh AAA cells I had.

The C9000 will put more charge into the cells during break in.

Here is the response I received regarding my AAA cells:
https://www.candlepowerforums.com/posts/2403650&postcount=14


----------



## junglemike

SilverFox, thanks very much for your valuable advice.


----------



## TorchBoy

junglemike said:


> I've read that it terminates the discharge process when cell reaches 1v.


It was only the very first release of the C9000 that terminated at 1 V. All the more recent ones terminate at 0.9 V.


----------



## stroberaver

Ok, so I'm in the market for a C9000, but naturally would prefer one of the later revisions without the cycle bug. I spoke to the UK distributor who said they received their stock at Christmas / end of last year. Is this likely to be recent enough to ensure getting a later revision? Anyone have an idea of when the revised versions entered the shipping/wholesale channels?

Thanks in advance.


----------



## TorchBoy

Very likely stroberaver. If you want to be really sure, get them to have a look at what batch number is on one before you buy it. It seems to take at least 2 or 3 months for new batches to get on the market but that will vary all over the place depending on stock levels of older ones.


----------



## stroberaver

Thanks for the advice - when I rang them they were unable to tell me the batch/revision numbers, but told me all their current Maha stock arrived last Christmas.


----------



## Doug.S

Doug.S said:


> 0G0IA
> 
> Maha is sending another replacement and will test this failed unit I'll return to them.


 

Replacement unit arrived and is another 0G0IA 

I ran 4 AA's "break-in" and worked just fine.

Installing a next batch of batts, the unit did not activate by inserting batt in any slot. Unplugged and re-plugged in power and it did start-up check OK and next set of batts now charging OK.

Just sent unit back to Maha so no news on cause of previous slot 1 failures.


----------



## Black Rose

Anyone know of a smaller wall wart that can safely be used with the C9000?

The wall wart that comes with the C9000 covers up 3 outlets on my power bar. I'd like to find one that is designed like the wall wart for the C800S.


----------



## Mr Happy

It's likely that if you found another wall wart of the same electrical specifications, it would be of similar size and weight.

However, I have a vague recollection of seeing some kind of short extender cable that allows you to plug in a wall wart without it covering up adjacent outlets. You could try looking for one of those maybe?


----------



## Bones

Black Rose said:


> Anyone know of a smaller wall wart that can safely be used with the C9000?
> 
> The wall wart that comes with the C9000 covers up 3 outlets on my power bar. I'd like to find one that is designed like the wall wart for the C800S.



These three prong adapters stand almost an inch tall, and the metal tang can be bent or cut back if necessary, which will almost always allow the utilization at least one adjacent outlet.

They're very common in hardware stores and home improvement outlets, so don't expect to pay Radio Shack's usurious price.

I have two in use at the moment to work around bulky adapters, one in a power bar and another in a wall outlet.


----------



## Bones

Black Rose said:


> Anyone know of a smaller wall wart that can safely be used with the C9000?
> 
> The wall wart that comes with the C9000 covers up 3 outlets on my power bar. I'd like to find one that is designed like the wall wart for the C800S.



These rather nifty 8" mini extension cords from Radio Shack are even purpose built to work around adapters.


----------



## Black Rose

Bones said:


> These rather nifty 8" mini extension cords from Radio Shack are even purpose built to work around adapters.


Those would do the trick.

I'll have to see if I can track down something like that here. We don't have Radio Shacks up here anymore. Radio Shack withdrew the RS naming rights in Canada when Circuit City bought out the RS licensee up here.


----------



## Black Rose

Found some. Had to order them from Tiger Direct.

I got a chuckle out of the packaging. Said it was RoHS compliant, and then the label on the cord basically says "Warning: Contains chemicals, including lead. Wash hands after handling".

I always assumed that RoHS meant lead free...


----------



## Mr Happy

Heh heh. They probably came from California.

California passed a law that requires any product to be carry a warning if it contains any substance that has ever been shown to be harmful. As a result, _everything_ in California now has such a warning attached.

Which reminds me, I must take this up with the water company. They put fluoride in tap water and that has definitely been shown to be harmful. They need to put this warning on everyone's water bill.


----------



## Black Rose

They were made in China (what a shocker) but the warning label did specifically name California.

They are supposedly Cables Unlimited liberator cables, but came in a Ziotek bag.


----------



## jusko

I read somewhere in this forum that the newer version C9000 will terminate the charging process when the battery voltage reaches 1.47V. I have version 0G0E02 and it does terminate before reaching 1.48V. That means I will never see 1.48V appears in my C9000.

But then I found that most of my batteries are prematurely "DONE" including the Powerex 2700 cells. Using the Refresh Analyze mode, my earlier version (the first launched version) of C9000 recorded around 2500-2600mah discharged capacity for the Powerex 2700. Due to missed termination of the early version, I exchanged it with a newer version 0G0E02 which showed a capacity of only around 2200-2300mah for the same cells.

I have run a capacity test for the same cells with another intelligent charger and found the discharged capacity of around 2500mah, quite similar to the early C9000.

I am disappointed that Maha adopted this "Voltage Termination" method resulting in premature termination in most of the batteries.

What do you think ? I want to see your view and comment please.

jusko


----------



## 45/70

jusko, did you let the C-9000 top off the cells for two hours _*after*_ "DONE"? That would add another 200mAh or so, as this is the "top off" charge method used. Basically, I'm with you though.

Dave


----------



## jusko

Hi, Dave, I used the "Refresh Analyze" mode and let it do all the thing until finished. I noticed there was "REST" (topping off) after the initial charging phase and then discharge and finally charging again.

Best Regards
jusko


----------



## 45/70

Humm, I'm too tired to look around for it, but I believe it was determined that in the "refresh and analyze" mode, the C-9000 does not top off during the rest period. This way the cells get a rest before discharging, and aren't "hot off the charger". Not sure though, you may want to look around.

Dave

Edit: After re-reading your post, I did see where you were using R&A mode. Missed that when I first posted.


----------



## Black Rose

I have a few Eneloops that reported 3.1% to 3.8% capacity loss during their first break-in cycle, so I decided to give them and the other June 2006 Eneloop AAs I have a refresh & analyze treatment.

I discharged the cells at 1A before performing the R & A. I used 1A for the charge and discharge values.

After the R & A cycle, the capacities reported were even lower than those from the break-in cycle (1948 after break-in, 1884 after R & A). The other cells showed similar capacity differences.

The Maha manual says that R & A is useful when the capacity of a cell needs to be determined, but if it's reporting lower capacities than the break-in cycle is it really useful?


----------



## SilverFox

Hello Black Rose,

The capacity of a cell is rated at a 0.2C discharge load. If you discharge at a higher rate, you can expect the capacity to drop off.

Also, keep in mind that while they are listed as 2000 mAh cells, they qualify that by also giving a minimum rating.

Tom


----------



## Mr Happy

Black Rose said:


> IThe Maha manual says that R & A is useful when the capacity of a cell needs to be determined, but if it's reporting lower capacities than the break-in cycle is it really useful?


One could argue it's useful because it's reporting the capacity likely to be obtained from a normal charge on the C9000. Since you don't normally charge cells with the slow timed charge that the break-in mode applies, the numbers from that are less directly applicable to real life.


----------



## Black Rose

OK, I see. So if I used 400 or 500 mA discharge rates, I'd see better numbers.

I just put another set on the C9000 for an R & A, 1000 mA charge and 500 mA discharge. Will see how that goes.


----------



## Mr Happy

Black Rose said:


> OK, I see. So if I used 400 or 500 mA discharge rates, I'd see better numbers.
> 
> I just put another set on the C9000 for an R & A, 1000 mA charge and 500 mA discharge. Will see how that goes.


You might see better numbers, but probably not a huge difference. NiMH are quite tolerant of variation in discharge rates and the measured capacity doesn't decrease all that much when you discharge at higher rates.

What makes more more difference in my opinion is the charging. When you do a break-in charge it is a bit like brimming your fuel tank in the car. It is like filling to the auto-cutoff, and then filling some more, and then trickling fuel in until the level is right up the filler pipe to the gas cap. On the other hand, a regular charge is like just filling to the auto-cutoff and stopping right a way.

Later model C9000s are particularly sensitive to this since they have a very conservative auto-cutoff. They stop charging quite a little time before the batteries are completely brimmed.


----------



## jusko

I found the latest version of C9000 uses the 1.48V cutoff rather than -△V if you would care to look at it at around that voltage.

But most cells won't be fully charged until the voltage is well beyond 1.5V. So the 1.48V is rather conservative.


----------



## TorchBoy

I have one from this year that stops at 1.46V or 1.47V with my Eneloops, before the top-up charge which takes them to 1.50V or sometimes 1.51V. Which version is yours, jusko?


----------



## Mr Happy

I have 0G0B01 and it stops at 1.48 V, but you have to watch very carefully to catch that. Once it stops charging the voltage drops in a few seconds to 1.47 V or lower so if you blink you will miss it.

The voltage actually drops all the way down to about 1.45 V and then slowly creeps up over the next hour to maybe 1.49 V on the top off charge before eventually resting back down to 1.44 V after two or three more hours.


----------



## jusko

TorchBoy said:


> ......Which version is yours, jusko?


 

My version is 0G0E02 which acts the same way as Mr. Happy's.

Best Regards
jusko


----------



## Handlobraesing

So, I've found this charger is no good at discharging batteries in not so good health or testing the capacity of batteries suffering a high internal resistance.

The termination voltage on discharge is fixed at 0.90v. The discharge current is fixed at 0.9-1A and you can not change it. Changing the current setting only changes the discharge duty cycle.

The discharge voltage is taken during on cycle, so the voltage is actually the voltage under 1A load. A deteriorating cell that works fine at 250mA that can't maintain 0.9v at 1A will cause this device to stop discharging immediately only to find that the battery still holds an open circuit voltage of 1.3v

If you want to cycle the cell to improve their health, this charger won't do it, because the discharging process will immediately terminate if the voltage under 1A load falls below 0.9v

So, 500mA discharge is really more like 1A discharge for one second, no discharge for one second, 1A discharge for one second and so on.

This charger is loaded with a lot of cool OPTIONS, but the method of modulating the current is flawed in my opinion.

Both the charging and discharging current is the maximum current and changing the setting only changes the 2 second time weighed average.


----------



## SilverFox

Hello Handlobraesing,

You have made an important discovery... Crap cells don't perform well. :devil:

I have found that it is far less frustrating to recycle crap cells and replace them with new cells that are performing well. However, there can be some educational opportunities from playing with crap cells.

If you want to play, try this...

Charge your cells at 1000 mA. When Done is displayed, set a timer for 3 hours. When the timer goes off, start a 500 mA discharge.

Record the capacity you get and compare it to the labeled capacity of the cell.

Leave the cells in the C9000 and set a timer for 30 minutes. Then do another discharge at 200 mA.

When that discharge is completed, once again, set the timer for 30 minutes, then do another discharge, this time at 100 mA.

Next, do a Break-In cycle. Once again, record the capacity and compare it to the labeled capacity.

Set a timer for 1 hour, then discharge at 500 mA. 

Record the capacity and compare it with what you got during the first 500 mA discharge. If you see an improvement in capacity, the cell is starting to recover and you can repeat this process again.

After 10 rounds of this, if your crap cells are going to recover, they should be at or above about 80% of their labeled capacity.

On the other hand, if your crap cells are still crap, recycle them and move on. If you have a secial "attachment" to them, find a crap application for them and don't be frustrated when they crap out on you. 

Have you tried running any healthy cells through charge/discharge cycles on the C9000? How did they do?

Tom


----------



## Handlobraesing

Simple. There is almost no difference in read-out voltage in 100mA or 1,000mA, because the voltage reading is taken under load and 100mA is just 1A at 10% duty cycle. 

The voltage falls below 0.90v(which is 0.95v at the terminals measured externally), then it immediately displays DONE Avail. cap 0mAh


----------



## Black Rose

SilverFox said:


> However, there can be some educational opportunities from playing with crap cells.
> 
> If you want to play, try this...


Wow, thats a lot of time to try and recover a set of cells. I guestimated that process would take approx 25 days for 2000 mAh cells.

It would be interesting to see how much electricity would be used by the C9000 during that process compared to the results (i.e. is it worth investing $X.00 of electricity to _attempt_ to revive the cells). 

As a test to see how much power is used by the C9000, I currently have it hooked up to an energy meter to see how much power it uses for a 1A discharge cycle followed by a break-in cycle. I noticed a sizable spike on my last electricty bill, so I'm curious to see how much the break-in cycles played into that.


----------



## SilverFox

Hello Handlobraesing,

OK, so your crap cells show 0 mAh under a 100 mA discharge on the C9000. What do you get after running the Break-In cycle?

Tom


----------



## Handlobraesing

SilverFox said:


> Hello Handlobraesing,
> 
> OK, so your crap cells show 0 mAh under a 100 mA discharge on the C9000. What do you get after running the Break-In cycle?
> 
> Tom



It wouldn't complete the break-in cycle. It would force charging at 2A * n% duty cycle and once it's done, it rests, and switch over to discharge, drops <0.90v and says "done". 

If the cell can't hold 0.90v at full one amp, MH-C9000 will terminate prematurely. The voltage measurement is taken under pulse load which causes the voltage to drop to what you'd get under 1A load.


----------



## Mr Happy

I think the important part of the break-in cycle is the charging part. If the 16 hour 0.1C charge did not improve the performance of the cell to the point where it can sustain any discharge at all, then the cell is toast methinks.


----------



## SilverFox

Hello Handlobraesing,

OK, we are making progress here...

So far your crap cells have 0 mAh capacity after a normal charge and a 500 mA discharge, and 0 mAh capacity after a 0.1C charge and 0.2C discharge.

Yet you claim that under a 250 mA constant load they work fine.

It's time to put them in a direct drive light, turn it on and let it run for around 4 hours. Hopefully you have a single cell light. If you need to run a pair of cells, you will have to watch it to make sure you don't ruin your crap cells further by reverse charging. 

At the end of this, you will need to jump start the cells to get them to have enough voltage to start the C9000. Once you get the voltage of the cell up to where the C9000 recognizes it, you can run another charge/discharge and see if you get past 0 mAh.

Tom


----------



## Handlobraesing

SilverFox said:


> Hello Handlobraesing,
> 
> OK, we are making progress here...
> 
> So far your crap cells have 0 mAh capacity after a normal charge and a 500 mA discharge, and 0 mAh capacity after a 0.1C charge and 0.2C discharge.
> 
> Yet you claim that under a 250 mA constant load they work fine.
> 
> It's time to put them in a direct drive light, turn it on and let it run for around 4 hours. Hopefully you have a single cell light. If you need to run a pair of cells, you will have to watch it to make sure you don't ruin your crap cells further by reverse charging.
> 
> At the end of this, you will need to jump start the cells to get them to have enough voltage to start the C9000. Once you get the voltage of the cell up to where the C9000 recognizes it, you can run another charge/discharge and see if you get past 0 mAh.
> 
> Tom



That's basically what I'm saying... because it only samples voltage under 1A load, it terminates prematurely, so it's not a useful discharge device to actually get say... discharge to 0.9v at 0.1A.


----------



## SilverFox

Hello Handlobraesing,

Actually, because of the pulsed discharge, it give slightly optimistic results compared to constant current discharging...

If you would like to do a comparison, you will need to pick up a CBA from West Mountain Radio, and a couple of new Alkaline AA cells. You will have to take some time and adjust the calibration of the CBA so that it is accurate at low current levels, then discharge a cell on the CBA at 100 mA with a discharge limit set to 0.9 volts, and also discharge another cell on the C9000 at 100 mA. You will find that the C9000 will give a slightly higher capacity.

When you move on from crap cells to healthy cells, what are you finding?

Tom


----------



## pobox1475

I just got a C9000 last week and am in the middle of running a couple break in cycles on some new Eneloop AAA & AA and old Rayocac NiMH. When that is done which mode should I use get the most accurate display of their capacities? I also have some really old AA NiCad's with the name Millennium on them but no current capacity listed. I had intended to see what performance they would give or attempt to revive them. Should I just toss them in trash?


----------



## Mr Happy

pobox1475 said:


> I just got a C9000 last week and am in the middle of running a couple break in cycles on some new Eneloop AAA & AA and old Rayocac NiMH. When that is done which mode should I use get the most accurate display of their capacities?


It depends on what you want to measure.

I'd say you will get the most accurate display of their capacities if you measure it in the way that corresponds most closely to how the cells will normally be used.

You should discharge the cells and then charge them on whichever charger and using whichever mode you normally plan to use. After this, rest them for a few hours or a day, and then discharge them on the C9000 using the discharge current that again most closely resembles your intended use. Conservatively you would probably use the highest 1 amp setting.

This procedure will tell you what you can actually expect from the cells (rather than a theoretical maximum that you will never likely see). You can compare this with the capacity reported on the break-in charge and see what the difference is. I have also found it interesting to charge on different chargers and discharge on the C9000 to see which chargers do best at supplying a full charge.


----------



## SilverFox

Hello Pobox,

At the end of the Break-In cycle, the capacity you see should come close to matching the labeled capacity of the cell.

With you NiCd cells, charge them at 1000 mA and discharge them at 500 mA and see what you get. If you think there is hope for them, they will also benefit from a Break-In cycle.

I might add that it is better to recycle than to toss in the trash...  

Tom


----------



## pobox1475

I am trying to keep it as simple as possible and hopefully match the cells in the process. From what you stated I can use the reading at the end of Break In to get an idea. I thought I might have to run a Refresh & Analyze or Cycle to get it.


> I might add that it is better to recycle than to toss in the trash...


Where can I do this and what kind of cell will they accept?


----------



## Mr Happy

pobox1475 said:


> I am trying to keep it as simple as possible and hopefully match the cells in the process. From what you stated I can use the reading at the end of Break In to get an idea.


Yes, you can. I have found the capacities reported by the break-in cycle to be quite repeatable and consistent. If one cell comes up low the first time round it will come up low the next time you test it too.


----------



## SilverFox

Hello Pobox,

As far as recycling goes, here are some places that may take your cells.

There are a couple of ways to evaluate cells. One is to compare their capacity according to what is listed on the label. Another is to check them under the same loads you will be using them under. If you happen to know that your lights draw 1000 mA, then you can check your cells under a 1000 mA load.

Tom


----------



## Handlobraesing

SilverFox said:


> Hello Handlobraesing,
> 
> Actually, because of the pulsed discharge, it give slightly optimistic results compared to constant current discharging...



That negates the theory that its method is IEC standard though. A standard is about running tests under same conditions and not about making the numbers look good. 

So for a 2500mA cell, discharge current should be 500mA to 0.9v not an alternation of 1 second on and 1 second off at 1A as done by MH-C9000. 

Alternating on 1 minute cycle instead would give the same time average current too, but I don't buy alternating between 1 minute at 1A and 1 minute at 0A as true 500mA. 

I think even 0.5Hz is way too slow to claim the average as the true current. It's slower than car turn signals. 






> When you move on from crap cells to healthy cells, what are you finding?
> Tom



Then it can measure capacity just fine, however it doesn't serve its true purpose. Let's say you have a 2.5Ah cell that provides service at 100mA level. You couldn't care less about the voltage the cell can sustain at 1A.

If your purpose is to analyze the amount of usable capacity loss under the same rate found during service, MH-C9000 can falsely reject a cell as 0mAh because it can't hold >0.9v at 1A load.


----------



## Mr Happy

I think that 1 A is a stroll in the park for a NiMH cell. If a cell can only manage 100 mA without voltage loss, then it is so totally wrecked that there is no real point trying to use it. You won't be able to charge it at currents much above 100 mA either without it getting too hot.

You can sometimes revive sick patients, but trying to revive corpses is more than most people consider worthwhile.


----------



## Burgess

Lots of good info here in this thread.

:wave:
_


----------



## Handlobraesing

Mr Happy said:


> I think that 1 A is a stroll in the park for a NiMH cell. If a cell can only manage 100 mA without voltage loss, then it is so totally wrecked that there is no real point trying to use it. You won't be able to charge it at currents much above 100 mA either without it getting too hot.
> 
> You can sometimes revive sick patients, but trying to revive corpses is more than most people consider worthwhile.



Remember MH-C9000 isn't just for AAs. It can do AAAs as well and since the highest capacity that's available today is 1Ah, a minimum discharge rate of 1C is rather harsh. If you're testing some 600mAh cells, you're loading them at 1.67C minimum.


----------



## bob_ninja

Mr Happy said:


> I think that 1 A is a stroll in the park for a NiMH cell. If a cell can only manage 100 mA without voltage loss, then it is so totally wrecked that there is no real point trying to use it. You won't be able to charge it at currents much above 100 mA either without it getting too hot.
> 
> You can sometimes revive sick patients, but trying to revive corpses is more than most people consider worthwhile.



While many/most decide that a cell is dead below 80% of original capacity, I see no harm in using older below 80% cells in low current apps. For instance, I use such cells in my wireless mouse which clearly uses very little current. They still last a long time, more than a week. Now clearly I am careful when charging them, always present and never during a night or while away.

So while in general 1A is not a huge load, for older cells that I still want to use it may not work well, as pointed out. Still I don't mind so long as the charger keeps charging them (which it does). The actual/precise capacity is not important. I just have several spares on standby.

Just wanted to point out there are plenty of apps using well below 1A for which we cannot get accurate capacity readings.


----------



## Handlobraesing

For true 100mA ish loading, I use a battery holder and a 10 ohm resistor and log the voltage over time on a software.

The only thing that's important is knowing the precise value of your resistor (it doesn't matter if it's 9.23 or 10.00 as long as you know it) and using ohm's law, you can calculate Ah and Wh.

Since it's actually not that important to precisely maintain 100mA (i.e. 80 to 120mA variation won't affect the capacity much) constant resistance approach works ok.

Unfortunately, the process is a pain in the butt without having a program that will automatically do the integration number crunching.


----------



## Black Rose

Black Rose said:


> As a test to see how much power is used by the C9000, I currently have it hooked up to an energy meter to see how much power it uses for a 1A discharge cycle followed by a break-in cycle.


In case anyone is curious, the test cycles noted above that I was monitoring with the power meter have completed.

Over the 46 hour period the MH-C9000 used a whopping 0.10 kWh of electricity. That's about half a cent worth of electricity in my area.


----------



## bob_ninja

Black Rose said:


> In case anyone is curious, the test cycles noted above that I was monitoring with the power meter have completed.
> 
> Over the 46 hour period the MH-C9000 used a whopping 0.10 kWh of electricity. That's about half a cent worth of electricity in my area.



Just don't bother. Consider any one of many 10A tools, heating elements and air conditioners. They use 10A * 120V about 1kW
So running a tool in a garage, air conditioning, etc. for one hour consumers a full kWh in a single hour. Our chargers by comparison are toys.


----------



## Mr Happy

Black Rose said:


> Over the 46 hour period the MH-C9000 used a whopping 0.10 kWh of electricity. That's about half a cent worth of electricity in my area.


That's nice to know. I was interested in that result because the rating plate on my C9000 power brick suggests it can consume up to 100 W or so. If it actually used that much power for 40 hours it would add up to 4 kWh. Fortunately it appears that the 100 W is the peak capacity and not the normal load.


----------



## Black Rose

bob_ninja said:


> Just don't bother. Consider any one of many 10A tools, heating elements and air conditioners. They use 10A * 120V about 1kW
> So running a tool in a garage, air conditioning, etc. for one hour consumers a full kWh in a single hour. Our chargers by comparison are toys.


I was just curious as I noticed a bit of a spike in electricity usage over my previous billing cycle and wondered if my chargeathons might have been the culprits.


----------



## Black Rose

Mr Happy said:


> That's nice to know. I was interested in that result because the rating plate on my C9000 power brick suggests it can consume up to 100 W or so. If it actually used that much power for 40 hours it would add up to 4 kWh. Fortunately it appears that the 100 W is the peak capacity and not the normal load.


The power meter showed a maximum load of 28 W and 0.23 A. Normal load appears to be 2 W and 0.2 A during the break-in.


----------



## SilverFox

Hello Handlobraesing,

I just wanted to put your crap cell into perspective...

I check new batches of alkaline cells that I pick up to make sure the Alkaline Shoot Out stays current. I just picked up some new cells, so I ran some tests on them.

Discharging at a constant 500 mA on the CBA, I ended up with around 1460 mAh. Discharging at 500 mA on the C9000, I ended up with around 1550 mAh.

Next I placed both cells in the C9000 and ran a discharge at 100 mA. The cell that had been discharged under a constant current ran for 305 minuts, and the other cell ran for 425 minutes.

I let the cells recover for a while then ran another 100 mA discharge on the C9000. The "CBA" cell ran for 59 minutes, and the other cell ran for 42 minutes.

I then did another discharge on the C9000 at 100 mA with the same cells. The "CBA" cell ran for 14 minutes and the other cell ran for 12 minutes.

Finally, I ran one more discharge at 100 mA. The "CBA" cell ran for 7 minutes and the other cell ran for 4 minutes.

Your crap cell that registeres 0 mAh under a 100 mA load is worst than an alkaline cell after it has been discharged 5 times. 

You are correct in that the IEC standard calls for constant current charging and discharging. Battery manufacturers don't use C9000 units to rate their batteries. However, in the consumer end of things, the C9000 comes closer to doing an IEC test than any other charger available. I don't think this function is avaliable on the hobby chargers either. At any rate my Schulze charger doesn't have a setting for running an IEC charge/discharge.

You are forgetting that NiMh cells are rated under constant current conditions. They are much more robust under pulse loads. This includes AAA cells.

Tom


----------



## TorchBoy

Tom, do those times for the C9000 need to be multiplied by 0.9 to give an accurate capacity? Or rather, 0.9 duty cycle x 0.1 amps / 60 minutes?


----------



## SilverFox

Hello Ian,

That is correct. While the mAh display of the C9000 is correct, to figure it from the time displayed requires multiplying the time by 0.9, then multiplying that by the current used.

Tom


----------



## Handlobraesing

SF. I just ran down a UltraLast brand alkaline on MH-C9000 @ "500mA" setting and I got 1406mAh.


----------



## SilverFox

Hello Handlobraesing,

OK, now let the cell recover for a few minutes and do another discharge on it using 100 mA as the discharge current.

Tom


----------



## Handlobraesing

SilverFox said:


> Hello Handlobraesing,
> 
> OK, now let the cell recover for a few minutes and do another discharge on it using 100 mA as the discharge current.
> 
> Tom



Tom,

I got ~1,100mAh @ 100mA setting on a brand new Duracell standard coppertop alkaline, which discharges at "100mA" to "0.9v". If it's anything like Energizer, I should be getting at least 2,000mAh as that's the 1.0v cut off spec at 100mA.

http://data.energizer.com/PDFs/E91.pdf

Could you repeat the experiment at 100mA on an alkaline and see if you get a completely different result?


----------



## Handlobraesing

I have a generic brand new alkaline on 3.0 ohm constant resistance discharge. I'll see what the available capacity is to 1.0, 0.9 and 0.8v by integration...

ULTRALAST brand regular alkaline:
Ta = 23°C
method: continuous integration
load = 3.0 ohm precision resistor

Istart = 0.45A Iend = 0.27A

Vterm, Amp-hr, watt-hr
0.8v	1.405	1.457
0.9v	1.244	1.316
1.0v	0.733	0.832
1.1v	0.410	0.490
Energizer... w/ 2013 exp date
0.8 1.346	1.412
0.9 1.245	1.325
1.0 0.898	0.992
1.1 0.415	0.485


----------



## SilverFox

Hello Handlobraesing,

I grabbed a couple of the same brand of cells and ran discharges at 100 mA. I got 2038 mAh from one cell, and 1994 mAh from the other one.

Looking at the Energizer data, they advertise around 2500 mAh when discharging at 100 mA down to 0.8 volts. 

I took the lower of the two cells and discharged it at 100 mA on the CBA down to 0.8 volts. The cell had rested for a few hours, so this may not be totally representative. However, I ended up with an additional 420 mAh. Now I am getting reasonably close to what the Energizer data sheet advertises, and these cells aren't even Energizer cells. 

I think the data from the C9000 is acceptable.

By the way, I took the same cell and it still discharged a little more on the C9000 after both of these discharges. This alkaline cell is performing better than your crap cell.

Tom


----------



## Nisei

I just received my Maha today and I've been reading a lot of interesting things here.
But one thing isn't clear to me; say I have an 800 mAh AAA battery which has been degraded to 500 mAh. When I'm using Break-In mode, should I enter the actual discharge capacity (500mAh) or the capacity written on the label (800 mAh) when I'm asked to set the battery capacity?
Also, when a battery has degraded does the actual discharge capacity become 1.0C?


----------



## Black Rose

Enter the labelled value, 800 mAh in this case.

The break-in cycle may revive the cell or at least give it some more capacity. It may take a couple of cycles, but it may come back to life.


----------



## pobox1475

> The break-in cycle may revive the cell or at least give it some more capacity.


 I assume the Break-In-Cycle is the best way to rejuvenate them. Would a standard Cycle(s) after a Break-In achieve similar results but save time? I am currently testing/doctoring about 16 1600 Rayovacs and have been doing so for 2 weeks now! Also should a Break-In be run on new Eneloops? Last question, I have been discharging my AA's at 300 and AAA @100 prior to starting the Break-In's (thus adding to the long times). Is this a good practice and should I use the Discharge in the future after I'm finished doctoring?


----------



## Black Rose

pobox1475 said:


> I assume the Break-In-Cycle is the best way to rejuvenate them. Would a standard Cycle(s) after a Break-In achieve similar results but save time?


The manual says to use Refresh & Analzye up to 3 times to try and rescue batteries. If the reported capacity is still low, then try a Break-In cycle.



> Also should a Break-In be run on new Eneloops?


There has been some debate about that one. Most folks here appear to do a Break-In on Eneloops and other LSD/Pre-charged cells.



> Last question, I have been discharging my AA's at 300 and AAA @100 prior to starting the Break-In's (thus adding to the long times). Is this a good practice and should I use the Discharge in the future after I'm finished doctoring?


It is better to discharge the cells before a Break-In cycle or even a normal charge cycle. I discharge my cells (AA or AAA) at 500 ma or 1000 ma.


----------



## Nisei

OK but what if, after trying a break-in, the capacity is still lower than the specs on the label? Should the actual discharge capacity then be considered as 1.0C? This also goes for Trustfire batteries: the specs are often bloated and sometimes the actual capacity is only 2/3 of the one on the label. Is it wise to check the actual discharge capacity and use that as 1.0C and ignore the specs on the label?


----------



## Black Rose

Nisei said:


> OK but what if, after trying a break-in, the capacity is still lower than the specs on the label? Should the actual discharge capacity then be considered as 1.0C?


This is my own opinion, but I think that the actual discharge capacity could be considered 1.0C, but that value will change over time, so it would need to be monitored.

One of the rules that SilverFox (our resident battery guru) uses is that for a new battery, if it's capacity comes in below 10% of the labelled capacity, he considers it to be a bad cell and returns it.

For a battery that is losing capacity with age/use, once it loses 20% of it's labelled capacity, it's recycled. As with anything, it depends on your own needs and what the cell is being used for. 



> Is it wise to check the actual discharge capacity and use that as 1.0C and ignore the specs on the label?


I believe that would be a safe assumption, but as the battery ages, that value will get lower over time, so what is 1.0C today could end up being 1.25C down the road and over-discharge the cell, causing more damage. Periodic capacity checks would be needed to make sure the cell isn't damaged.


----------



## Nisei

Great, thanks for the reply.


----------



## Mr Happy

Nisei said:


> OK but what if, after trying a break-in, the capacity is still lower than the specs on the label? Should the actual discharge capacity then be considered as 1.0C? This also goes for Trustfire batteries: the specs are often bloated and sometimes the actual capacity is only 2/3 of the one on the label. Is it wise to check the actual discharge capacity and use that as 1.0C and ignore the specs on the label?


Doesn't Trustfire imply a Li-ion cell? This discussion and the C9000 charger is very definitely for the NiMH chemistry. Break-in charges do not apply to Li-ion cells.

As to the actual capacity entered for the break-in charge, just use the nominal label capacity. The break-in process uses a low current and deliberately and harmlessly overcharges the cell in any case. When it discharges it stops when the cell voltage reaches 0.9 V. So there is no cause to worry about overcharging or over discharging if the cell doesn't perform to the label capacity.

Here is the reason. NiMH cells can lose apparent capacity and performance if stored for a long time without being used, or if given small charge discharge cycles without ever being fully discharged. The break-in process is designed to rejuvenate such cells and restore them to full capacity. If a cell does not recover after this process it may be considered for recycling since its performance has permanently degraded.


----------



## pobox1475

I have about 20 AA Rayovac 1600 Mah since 2005/6 that have not been used. With my new C9000 I have been running them through the Break In. I have started keeping track of capacities now that I am on the 2nd go round. The first four to finish came up as: 1036,1114,1133 and 1476. So once I run them through a third cycle and the three that are low do not improve to >=1280 it's off to recycler?


----------



## Black Rose

pobox1475 said:


> I have about 20 AA Rayovac 1600 Mah since 2005/6 that have not been used. With my new C9000 I have been running them through the Break In. I have started keeping track of capacities now that I am on the 2nd go round. The first four to finish came up as: 1036,1114,1133 and 1476. So once I run them through a third cycle and the three that are low do not improve to >=1280 it's off to recycler?


It's personal choice really...it depends on how critical their performance is for what you need them for. 

I have some 2000 mAh Rayovac cells like that...I just use them in things like toothbrushes.


----------



## lengendcpf

I thought I learnt what I am supposed to know about charging rechargeables..I used to put in battery into a charger. The light lights up, after charging, the light goes off. I use the battery..

Now this charger confuses me.

If after the charger says done, meaning I can straight away take out the batteries? Or should I let them stay for 2 more hours of trickling charge for them to get fully charged? What will the display for that battery show?

Also, does the charge current makes any difference to the 2 hours of trickling charge? i.e. I charge a 2000mah battery using 500ma and another one using 1000ma current?


----------



## Black Rose

When the charger says done, you can take the batteries off if you want. Leaving the batteries on the charger for a couple of hours will just top them up.

I don't think the charge current makes any difference for the trickle charge. The trickle charge is 100 mA for 2 hours.


----------



## lengendcpf

Hi Black Rose, thanks for replying.


Regarding the refresh and analyse and also the break in..

Cause I read regarding rechargeables, most manufacturers say after few charges/discharges, the batteries will reach their rated capacities..

So is the refresh and analyse and the break in, necessary to perform?


One thing I like about this charger is the ability to set different levels of current. And can fast charge all 4 bays at the same time. 2A. Wow!


----------



## Nisei

I notice that Maha says the C9000 supports batteries up to 20,000 mAh. On the other hand they tell you not to charge at a rate below 0.3C. That contradicts because the highest charge current is 2000 mA making it only suitable for batteries up to 6000 mAh. Anyone else thought about this?


----------



## Unforgiven

Nisei said:


> I notice that Maha says the C9000 supports batteries up to 20,000 mAh. On the other hand they tell you not to charge below 0.3C. That contradicts because the highest charge current is 2000 mA making it only suitable for batteries up to 6000 mAh. Anyone else thought about this?





The MAHA MH C-9000 is designed for AAA and AA batteries. I have not found any of those size cells rated over 15% of the 20,000 mAh that you mentioned. Unless jumpers or some kind of adapters are used to try to charge batteries that it is not designed to charge, it is a non issue. 

If one were to actually read through the MH-C9000 threads they would likely find that the updated firmware has changed a few things.


----------



## Nisei

A few years ago 1800 mAh was the maximum capacity you could buy. Now it's getting close to 3000! All I wanted to say is that Maha states this charger is future proof but as long as 2000 is the max charging current you can't charge anything higher than 6000 mAh if you stick to their 0.3C rule.


----------



## Black Rose

lengendcpf said:


> Regarding the refresh and analyse and also the break in..
> 
> Cause I read regarding rechargeables, most manufacturers say after few charges/discharges, the batteries will reach their rated capacities..
> 
> So is the refresh and analyse and the break in, necessary to perform?


They might not reach their rated capacity, but they will get closer to it in most cases. 

Break-in mode just gives the cells a good start in their life and will also tell you if a new battery is bad.

Refresh and analyze is a quick way to find out if your batteries are losing any capacity.

One quick way to put a few charge/discharge cycles on the batteries is to use the Cycle mode. It charges and discharges X number of times, at the charge and discharge rates you choose.


----------



## lengendcpf

For 1.2V AA/AAA what is the voltage that determine that battery is bad?

Also the cell must be at what percentage of their manufacturer's rated capacity? i.e. an AAA cell rated at 850mAh but gives 805mAh(94.71%), is this cell ok?


----------



## Black Rose

lengendcpf said:


> For 1.2V AA/AAA what is the voltage that determine that battery is bad?


I have no idea. I think most use the capacity reported from the Break-in or Refresh and Analyze modes to determine if a battery is bad.



> Also the cell must be at what percentage of their manufacturer's rated capacity? i.e. an AAA cell rated at 850mAh but gives 805mAh(94.71%), is this cell ok?


Is it a new cell or one you already had? Either way, that's a good one. It's only 5.3% off from it's labelled capacity.


----------



## KuoH

That's the most logical way I see of making a determination. I am now also labeling my batteries with the last test date and reported capacity so I can monitor the progression of each cell over time. I should add also, that I don't believe there is a magical number at which one should just throw away an old cell. It's really a matter of personal preference, but I have some cells that are at only 50% or so, which won't see any EDC out of the house duty, but would be perfectly good for any around the house, voltage compatible, low to moderate drain devices.

KuoH



Black Rose said:


> I think most use the capacity reported from the Break-in or Refresh and Analyze modes to determine if a battery is bad.


----------



## lengendcpf

Hi, I am doing a refresh and analyze mode for one of my Recyko 2050mAh AA battery now.

At this moment, the slot is showing REST(after topping up, so now is the 2 hours rest period), I can only see: 24 min(time elapsed), 1.44 V and 886mAh (capacity?).


My question is why doesn't it show close to 2000mAH, since it has finished topping?

Btw the way, I am also doing a R&A for my Recyko 850mAh AAA battery at the same time, it shows: 70 min(time elapsed), 1.46 V and 55mAh (capacity?)

Is my charger's readings normal?


----------



## lengendcpf

Let me answer my own question.

Actually the capacity show after the topup during the rest mode is is the amount of energy put into the batteries. This number does not equal to the battery’s capacity as it is dependent on the amount of charge already in the battery as well as the battery’s internal resistance.

Ok, so my charger is working normally.


Some people have asked, for break in mode, if the battery capacity is xx50mAh, what should be the capacity to be entered?

Answer is Simply round up to the next capacity. For 2650 mAh battery, use 2700mAh capacity. 

Actually all these can be found here


----------



## pobox1475

From what I gathered the only number that means any thing until Break In is finished is the time.


----------



## lengendcpf

This is the a very informative review.

Let you know more about your C-9000.


----------



## lengendcpf

Regarding the break in mode, can I just let the charger complete the 1st 16 hours of charge, then remove the battery? Does this consider "break in"? Or I must let it continue its discharge and another 16 hours of charge?


----------



## Black Rose

No, that is not a proper "break in". You need to let if complete it's full cycle.

The idea behined break in mode is to apply a steady charge for 16 hours, rest for an hour, discharge the cells to see how much energy the cell retained during from that 16 hour charge, and then charge it up again.


----------



## lengendcpf

Black Rose said:


> No, that is not a proper "break in". You need to let if complete it's full cycle.
> 
> The idea behined break in mode is to apply a steady charge for 16 hours, rest for an hour, discharge the cells to see how much energy the cell retained during from that 16 hour charge, and then charge it up again.


 
But don't the discharge is just to find out the actual capacity of the cell?

Is there any documented proof that the proper break in must be done this way?


----------



## Black Rose

lengendcpf said:


> But don't the discharge is just to find out the actual capacity of the cell?


 
Yes, the discharge is used to find the actual capacity of the cell.



> Is there any documented proof that the proper break in must be done this way?


Break In mode follows the *IEC industry standard* for capacity analysis, but is also referred to as a forming charge which gives the batteries a better start in life, which will in turn make them last longer.


----------



## Mr Happy

There's nothing to prevent you stopping after the first charge of course, but the discharge capacity is useful to know and two charges probably does a slightly better job of forming and conditioning than just the first charge.


----------



## SilverFox

Hello Legendcpf,

If you have no need or use for the capacity information, feel free to use the cell after the 16 hour 0.1C charge.

Tom


----------



## lengendcpf

Thanks Black Rose, Mr Happy and Silverfox for the reply, I think the most I drop the batteries in for 16 hours; just let them form the charge/capacity and use them..


----------



## pobox1475

I am trying to learn the "ins & outs" of battery care. My C9000 has been running break in cycles non stop for the past three weeks. I have 16 1600 mAh Rayovac's that have sat idle for about three years and only topped off on a Rayovac charger a few times. I have completed two complete run troughs keeping track of capacities the second go round. The lowest two being 898 & 1070 mAh and the highest 1509 & 1516. Now heres where the questions arise;

I was under the impression that break in cycles are good for the cells and the more run on them the better. During the third cycles I started with the cells that showed the lowest capacities and have found that the the first 4 have shown a _reduction. 898 to 840, 1070/1020, 1092/1045 and 1114/1081. _I am now concerned and want to know if this indicates that the cells are on their way out and should be given up on? Or if running back to back to back break in's is doing more harm than good? If these are basically poor cells (brand, original capacity or age wise) I can live with out them and get some new 2700's. I still have another dozen to work on and the top eight registered 1320 to 1516 mAh which I guess is not too bad. Should I continue with a third break in on the remaining cells? I intend to recycle any that are not worth using, which I assume would be the first 4 and any others that fall below 1200 mAh, which would be 75% of marked capacity. Let me know if there is a more semi-official guide line for drawing the line on performance/capacities.


----------



## Mr Happy

pobox1475 said:


> I was under the impression that break in cycles are good for the cells and the more run on them the better.


Well no, not exactly. Like all things, break-in cycles are good in moderation. If you do too many of them you will wear out your cells.

A tip when doing more than one break-in cycle, is don't run them back-to-back. Since a complete cycle is charge-discharge-charge, you should run a discharge at 0.2C after the first cycle. If that shows an improvement, run another break-in, otherwise don't.

So your sequence would be break-in; discharge; break-in; discharge etc.



> I can live with out them and get some new 2700's


Dude, what are you thinking of?! If you have cells that sit idle and want to replace them, get LSD cells like Eneloops. 2700's are possibly the worst cells you could buy unless you re-charge and use them daily.


----------



## pobox1475

> If you have cells that sit idle and want to replace them, get LSD cells like Eneloops. 2700's are possibly the worst cells you could buy unless you re-charge and use them daily.


 I was thinking of 4 or 8 2700's for use when I could use extra power (night fishing) and neglected to mention that I have a dozen AA & AAA Eneloops on hand and discharge each cell before a break in. The break in's generally were run a few days apart. Not actually "back to back to back". I have read in a thread here that two or three break in's are a good idea for a brand new or older cell that needs rejuvenation. I assumed that three would be more than sufficient and would do _no _harm. I also read that a break in or two is good for new Eneloops. Is this true?


----------



## Mr Happy

What I was suggesting about the break-in cycles is that the cell will be charged at the end of the cycle. So for efficiency when doing more than one break-in, you could do it like this:



Code:


BREAK-IN                  DISCH       BREAK-IN
charge-discharge-charge | discharge | charge-discharge-charge | etc...

If the second discharge gives a higher capacity than the first (break-in) discharge, then continue. Otherwise don't do any more break-in cycles.

The timed conditioning charge does put some wear on the cell. For this reason a conditioning charge is only advised every 25 charges or so rather than every time.

If you know and understand the advantages and disadvantages of LSD cells vs. 2700's then never mind what I said. But do bear in mind the early failure and high self-discharge that so many people have reported of 2700 cells. You may be better off carrying a spare set of Eneloops in the long run.

It's possible that a break-in or two is beneficial for new Eneloops. The truth is that opinions vary and it's hard to say with certainty either way. I have tested Eneloops before and after break-in cycles, and honestly I find it hard to see any difference in performance.


----------



## pobox1475

> BREAK-IN DISCH BREAK-IN
> charge-discharge-charge | discharge | charge-discharge-charge | etc...


 This is the procedure I have been using.



> If the second discharge gives a higher capacity than the first (break-in) discharge, then continue. Otherwise don't do any more break-in cycles.


 I should have took note of the readings after the first runs. Now my only option to gauge any improvement (or opposite) is to run a third.



> But do bear in mind the early failure and high self-discharge that so many people have reported of 2700 cells. You may be better off carrying a spare set of Eneloops in the long run.


 Figured they would have fairly high self discharge but did not know about failures. I guess that additional 700 mAh on paper had my attention. I will take your advice and utilize the Eneloops.



> It's possible that a break-in or two is beneficial for new Eneloops. The truth is that opinions vary and it's hard to say with certainty either way


 I plan to run a couple just to ensure I don't have a rare dud. If anyone has strong reason to believe running break in's on Eneloops is a mistake, please chime in.


----------



## Mike_FR

Hi,

I recently ordered a MAHA C9000 at Kaidomain and infortunately it has a defective slot#2 just after unpacking.
After a look at the product case, I found a cross at the second slot :thinking:

Does anybody has already had such bad experience with kaidomain ?

Does anybody has already had a defective slot on a C9000 ?

The slot#2 is not able to charge and switch to trickle charge after settings (Done is not set near the slot number when it does that).


Thanks for your advice.


----------



## pobox1475

> I recently ordered a MAHA C9000 and infortunately it has a defective slot#2


 Your charger has a three year warranty, so if dealer is no help then I'm sure MAHA will take care of you.


> Done is not set near the slot number when it does that


 Not sure exactly what you mean. What ever option you choose for slot #2 nothing happens? Is it applying current to the cell? Will it give you the voltage? I assume you are stating than after you use #2 it never finishes with the "Done" indicator. Have you tried various cells in that slot?


----------



## Mike_FR

Yes, but sending it back and forth will cost more than the product itself.

Charging is not working in any case (charge mode, break-in, refresh/analyse). After inserting the battery and selecting the current value, it starts, but immediately switch to a low current value (some milliamps). The voltage seems correct. I've tried lot of cells and all of them worked fine on the others slots.


----------



## pobox1475

> Yes, but sending it back and forth will cost more than the product itself.


 I would call MAHA. I'm sure they would be interested in getting their hands on your unit to trouble shoot the issue. They may even cover your shipping cost. I have heard that their C.S. is outstanding .


----------



## Mike_FR

I'm located in France (European country).
Don't know if the Maha C.S. is covered in this area. There are no Maha resellers in my country.


----------



## Anders

Hello Mike_FR, Welcome to CPF:twothumbs

Maybe you can contact Maha in UK if you don't find any resellers in France
http://www.mahaenergy.co.uk/

I bought my C-9000 from US, I contacted Mahaenergy here in sweden when it became defective, they changed it immediately.

There was no mahaenergy in sweden at the time C-9000 was introduced.

This one is working like a charm.

Anders


----------



## TorchBoy

pobox1475 said:


> I have heard that their C.S. is outstanding .


That was probably from me. It is. :thumbsup:



Anders said:


> There was no mahaenergy in sweden at the time C-9000 was introduced.


Similarly here, but it was no problem (apart from the delay and slight hassle). I suspect I may have had the first two in New Zealand, after they replaced my malfunctioning first unit.


----------



## Niconical

Hello. 

I’m new to this thread, but I just got a Maha C9000 charger, and I have a few questions please. 

In case it is relevant, the serial code on the back of the charger is 0H0BB. 

In no particular order....

1. The manual recommends charging “not below 0.3C and not above 1.0C”. 

My eneloop AA (previously tested on a La Crosse BC700) are all 2100 or so mah. 
So, putting it halfway between the recommended levels I will charge them at 1500mah, and the AAA at around 600mah, both around 0.7C. 

Is that a good idea or is it best to be higher/lower?

2. When I insert a AA, it sits level. When I insert a AAA, it first sits at an angle, with the positive higher than the negative. The charger detects it fine, but it looks like if I push a lot harder it will slot down to level. Is it supposed to be at that angle, or should I push down hard so it is level?

3. What is the difference between top-off charging current (100mah) and maintenance charging current (10mah) ?

Thank you


----------



## Black Rose

I normally charge my cells at 0.5C of their labelled capacity. 
In this case Eneloop AA at 1000 mA and my AAA at 400 mA.

When I insert AAA cells (any brand) into the C9000, I roll them a bit to get them to seat better in the charger.


----------



## Bones

Niconical said:


> ...
> 1. The manual recommends charging “not below 0.3C and not above 1.0C”.
> ...



Item 13 of the Eneloop Facts & FAQs recommends against charging at rates that will complete a charge in under two hours.

Accordingly, the maximum rate recommended for the Eneloop AA and AAA cells are, respectively, 1000mAh and 400mAh.

You will have noted that the default charge rate for the MH-C9000 is also 1000mAh, which makes charging the Eneloop AA cell an insert n' go proposition.

Incidentally, the charge rate should be based on the capacity stated on the cell and not its consumer measured capacity.



Niconical said:


> ...
> 2. When I insert a AA, it sits level. When I insert a AAA, it first sits at an angle, with the positive higher than the negative. The charger detects it fine, but it looks like if I push a lot harder it will slot down to level. Is it supposed to be at that angle, or should I push down hard so it is level?
> ...



Unless they've changed the basic design of the MH-C9000, the AAA cell should sit parallel with it's charging bay, so they may not be properly seated. Rather than push it straight down though, try seating the cell in the bottom contact and then pushing the cell firmly towards the bottom contact while lowering it into the the opening for the top contact.

The idea is to slip rather than snap them into place, which is less stressful on the cells and charger.



Niconical said:


> ...
> 3. What is the difference between top-off charging current (100mah) and maintenance charging current (10mah) ?
> ...



The terms are more or less self-explanatory.

The top-off charge is applied at the end of the primary charge cycle, and is intended to 'top' off the amount of charge in the cell at a rate that will miniumize the amount of current that is converted to heat.

The maintenance charge follows the top off charge. It is intended to offset the self-discharge that NiMH cells experience.

Since the Eneloop are low self-discharge cells, they don't benefit from a maintenance charge as much as other NiMH cells.

Regardless, it is generally believed that prolonged maintenence charging may be more harmful than beneficial to all NiMH cells.


----------



## Mr Happy

Niconical said:


> 1. The manual recommends charging “not below 0.3C and not above 1.0C”.
> 
> My eneloop AA (previously tested on a La Crosse BC700) are all 2100 or so mah.
> So, putting it halfway between the recommended levels I will charge them at 1500mah, and the AAA at around 600mah, both around 0.7C.
> 
> Is that a good idea or is it best to be higher/lower?


You can charge AA Eneloops at any rate up to 2000 mA on the C9000. What you may find is that if you charge 4 cells at 2000 then the charger may get a little warm, which also heats up the cells. To keep things slightly cooler, I tend to use 1600 or 1800 mA instead. But if you are not in a hurry, the default 1000 mA rate is fine too.

For an AAA Eneloop, 600 to 800 mA will be fine.


> 2. When I insert a AA, it sits level. When I insert a AAA, it first sits at an angle, with the positive higher than the negative. The charger detects it fine, but it looks like if I push a lot harder it will slot down to level. Is it supposed to be at that angle, or should I push down hard so it is level?


AAA cells in the C9000 are a bit tricky. You need to place the negative end first, press it down firmly, and then push down the positive end. I don't have the charger in front of me, but I am fairly sure the cell should sit right down into the slot.


> 3. What is the difference between top-off charging current (100mah) and maintenance charging current (10mah) ?



The top-off charge happens for two hours after a normal charge says "DONE". It helps the cells to get a fuller charge. The maintenance charge happens after that for as long as the cells sit in the charger.



> Thank you


You're welcome.


----------



## Niconical

Thank you for all the replies


----------



## TorchBoy

Niconical said:


> So, putting it halfway between the recommended levels I will charge them at 1500mah, and the AAA at around 600mah, both around 0.7C.
> ...
> 3. What is the difference between top-off charging current (100mah) and maintenance charging current (10mah) ?





Bones said:


> Accordingly, the maximum rate recommended for the Eneloop AA and AAA cells are, respectively, 1000mAh and 400mAh.


Charge rates are in mA (current), not mAh (capacity). I charge at 1000 mA and 400 mA (like Bones meant to say) for 2000 mAh and 800 mAh capacity cells respectively. If you want to spend less time charging them then use higher charge rates.



Niconical said:


> 2. When I insert a AA, it sits level. When I insert a AAA, it first sits at an angle, with the positive higher than the negative. The charger detects it fine, but it looks like if I push a lot harder it will slot down to level. Is it supposed to be at that angle, or should I push down hard so it is level?


Yes, push harder, unless something is bent. You're inserting negative end first, right?


----------



## pobox1475

> AAA cells in the C9000 are a bit tricky. You need to place the negative end first, press it down firmly, and then push down the positive end.


 Also use the opposite motion for AA. Insert positive (top) end first, then negative (bottom).


----------



## Mr Happy

pobox1475 said:


> Also use the opposite motion for AA. Insert positive (top) end first, then negative (bottom).


Actually, I prefer not to do that as it can rip the plastic cell covering where it overlaps at the bottom. I prefer to insert and remove AA cells by pushing the cell down to compress the negative spring and allow the positive button to move freely in and out of the contact area.


----------



## Black Rose

Mr Happy said:


> Actually, I prefer not to do that as it can rip the plastic cell covering where it overlaps at the bottom. I prefer to insert and remove AA cells by pushing the cell down to compress the negative spring and allow the positive button to move freely in and out of the contact area.


That's what I do as well, even though the manual indicates the opposite.


----------



## shuter

You can't go wrong using a charge rate of .5C for all NiMH batteries including Eneloops. The C-9000 is a great product and I have found Maha customer service to be outstanding.


----------



## Grayson73

I just received the MH-C9000.

I have a lot of old cells. If I've understood what I've read in this thread, I should run a break-in or break-in + discharge + break-in rather than refresh&analyze 2x or 3x to revive old cells?


----------



## krayzeemofo

Mr Happy said:


> ...
> For an AAA Eneloop, 600 to 800 mA will be fine.
> AAA cells in the C9000 are a bit tricky. You need to place the negative end first, press it down firmly, and then push down the positive end. I don't have the charger in front of me, but I am fairly sure *the cell should sit right down into the slot*.
> ...



I just got the charger today and I can confirm that it charges both at an angle as well as flush. I was looking at the charger itself, and it seems that it has 2 notches; perhaps one is meant for AAA, and the other for AA? That being said, I still wonder what the proper orientation is for AAA cells in the C9000...hm...


----------



## fireguy

Mr Happy said:


> Dude, what are you thinking of?! If you have cells that sit idle and want to replace them, get LSD cells like Eneloops. 2700's are possibly the worst cells you could buy unless you re-charge and use them daily.



I'd like to take a moment to show my ignorance of batteries here. 

What is wrong with 2700's? I would have thought that the higher capacity would make them desirable? I understand the concept of LSD cells where the self-discharge is considerably less. Would a normal NiMH at 2000 maH be preferred over a 2700? Is it because of the self discharge, and taking a percentage of 2700 is larger than 2000? (eg: 10% of 2700 = 270, 10% of 2000 = 200) I am a noob here, so I hope my question isn't too silly .


----------



## Black Rose

krayzeemofo said:


> I just got the charger today and I can confirm that it charges both at an angle as well as flush. I was looking at the charger itself, and it seems that it has 2 notches; perhaps one is meant for AAA, and the other for AA? That being said, I still wonder what the proper orientation is for AAA cells in the C9000...hm...


Yes, the different notches are for AA and AAA cells.

As for the proper orientation, it's noted in the manual, although I do not follow their recommendations.

I insert both AA and AAA negative end first and then push the cell down so the positive end of the cell makes proper contact. Less chance of torn wrappers.


----------



## jayflash

Maybe I'm not remembering correctly, but I thought it was established that a 1C charge rate was more beneficial for NiMH cells, which had already been broken in and in normal use, than a 0.5C rate. If that's accurate wouldn't charging an Eneloop or Hybrid AA cell be better at a 1500mA - 2000mA rate?

Thanks for any replies - I've gotta keep refreshing my memory.


----------



## snakyjake

fireguy said:


> I'd like to take a moment to show my ignorance of batteries here.
> 
> What is wrong with 2700's? I would have thought that the higher capacity would make them desirable? I understand the concept of LSD cells where the self-discharge is considerably less. Would a normal NiMH at 2000 maH be preferred over a 2700? Is it because of the self discharge, and taking a percentage of 2700 is larger than 2000? (eg: 10% of 2700 = 270, 10% of 2000 = 200) I am a noob here, so I hope my question isn't too silly .



From what I've read, it will take approx 6 months of self-discharge before a 2700 matches the LSD. Also read that 2700 may be more fragile if dropped, but don't have any evidence of this. Dropped on cement? Carpet? What if the battery is in my flashlight, will that protect the battery too? Too many questions, no good tests.

I'll be buying 2700 for my devices that I use often. LSD for devices that don't get used much.

...unless someone has evidence of 2700 problems, or can show evidence that LSD is superior in all ways.


----------



## krayzeemofo

Black Rose said:


> Yes, the different notches are for AA and AAA cells.
> 
> *As for the proper orientation, it's noted in the manual, although I do not follow their recommendations.*
> 
> I insert both AA and AAA negative end first and then push the cell down so the positive end of the cell makes proper contact. Less chance of torn wrappers.


 

I must have missed it then, or perhaps my wording didn't convey what I meant, lol. Are the AAA cells *supposed* to sit at an angle with the positive side higher than the negative?

Thanks


----------



## Black Rose

krayzeemofo said:


> Are the AAA cells *supposed* to sit at an angle with the positive side higher than the negative?


Good question. I use the lift rod on the back of the charger to allow more airflow around the charger.

I'll have to check when I get home, but I think the AAA cells might sit at a bit of angle if they are not fully seated. 
Whenever I put AAA cells in the C9000, I always rotate them a bit to make sure they are fully seated.


----------



## krayzeemofo

Black Rose said:


> Good question. I use the lift rod on the back of the charger to allow more airflow around the charger.
> 
> I'll have to check when I get home, but I think the AAA cells might sit at a bit of angle if they are not fully seated.
> *Whenever I put AAA cells in the C9000, I always rotate them a bit to make sure they are fully seated*.


 
So then they are flush against the charger like AA cells? It just seems that in order to pop the AAA cells such that they are flush requires a bit of force when, to me anyways, it doesn't seem necessary when it *seems* to charge/function fine with the AAA cells at an angle/not parallel with the charger. The last thing I want to do is damage the cells or the charger which is why I am trying to find out what the official/generally accepted way of charging AAA cells is 

Thanks


edit: I just noticed that you are located in Ontario, where did you get your C9000 and where do you normally get your battery/battery accessories? I ended getting mine from thomas-distributing, but was wondering if there was any place closer/in Canada other than paulsfinest.


----------



## Black Rose

krayzeemofo said:


> edit: I just noticed that you are located in Ontario, where did you get your C9000 and where do you normally get your battery/battery accessories? I ended getting mine from thomas-distributing, but was wondering if there was any place closer/in Canada other than paulsfinest.


I got my C9000 and C800S from PaulsFinest when the Canadian dollar was stronger.

I get my Eneloops at Costco, Duracell Pre-Charged at Mountain Equipment Co-op, and Rayovac Hybrids at Wal-Mart.


----------



## Mr Happy

I don't have my C9000 in front of me, but I think the AAA cells are supposed to sit right down in the bottom of the charging slot (so that they can make good contact with the heat sensor). If they don't want to do this easily, try wiggling them a bit.

Given the way the charger contacts are designed, you have to seat the negative end first, and then push down on the positive end until the battery sits level.


----------



## pobox1475

> Rayovac Hybrids at Wal-Mart.


 How are they compared to Eneloops? I have never seen any LDS's at my local Wal-Marts 

Also I am so  cause I just moved into a house and one of the first few boxes I opened contained my C9000...


----------



## Black Rose

pobox1475 said:


> How are they compared to Eneloops?


They are good batteries, but not as strong as the Eneloops.

My Hybrids have lost a bit of capacity (approx 60 mAh) after 9 months of regular use in Wii remotes and a scanner.


----------



## pobox1475

^ Thanks, I'll stick with the Sanyo's.


----------



## krayzeemofo

Black Rose said:


> I got my C9000 and C800S from PaulsFinest when the Canadian dollar was stronger.
> 
> I get my Eneloops at Costco, Duracell Pre-Charged at Mountain Equipment Co-op, and Rayovac Hybrids at Wal-Mart.


 
thanks 



Mr Happy said:


> I don't have my C9000 in front of me, but I think the AAA cells are supposed to sit right down in the bottom of the charging slot (so that they can make good contact with the heat sensor). If they don't want to do this easily, try wiggling them a bit.
> 
> Given the way the charger contacts are designed, you have to seat the negative end first, and then push down on the positive end until the battery sits level.


 
so you DO have them right down to the bottom? I'm just looking for confirmation before I go around possibly damaging something, lol.


----------



## fireguy

krayzeemofo said:


> edit: I just noticed that you are located in Ontario, where did you get your C9000 and where do you normally get your battery/battery accessories? I ended getting mine from thomas-distributing, but was wondering if there was any place closer/in Canada other than paulsfinest.



Hi,

Just to chime in, I'm also in Ontario. I purchased my M9000 on ebay from a seller in PA for $40 USD. His id is "new-bliss-tech" and the unit has a new date code and was received in under a week. I was extremely happy with the purchase from this seller.

I just bought some Enerloops from Costco this morning. For $23 it included 6 AA, 2 AAA and two each of the C and D adapters. I've normally bought batteries on eBay, but have recently learned that you get what you pay for.

John


----------



## krayzeemofo

fireguy said:


> Hi,
> 
> Just to chime in, I'm also in Ontario. *I purchased my M9000 on ebay from a seller in PA for $40 USD.* His id is "new-bliss-tech" and the unit has a *new date code* and was received in under a week. I was extremely happy with the purchase from this seller.
> 
> I just bought some Enerloops from Costco this morning. For $23 it included 6 AA, 2 AAA and two each of the C and D adapters. I've normally *bought batteries on eBay, but have recently learned that you get what you pay for.*
> 
> John


 
I suppose I should've asked before I bought, lol.

What is the date code? (I don't have mine in front of me, but I think mine was 0G0K0 or something like that - I am sure of the 0G though). I would have thought that thomas-distributing sold the most number of the C9000 and, therefore, has the latest revisions/builds.

Also, is the last line in your post referring to the quality of just batteries or the battery charger as well? I'm assuming its just the batteries but I want to make sure.

Thanks


----------



## fireguy

krayzeemofo said:


> What is the date code? (I don't have mine in front of me, but I think mine was 0G0K0 or something like that - I am sure of the 0G though). I would have thought that thomas-distributing sold the most number of the C9000 and, therefore, has the latest revisions/builds.
> 
> Also, is the last line in your post referring to the quality of just batteries or the battery charger as well? I'm assuming its just the batteries but I want to make sure.
> 
> Thanks



My date code is 0H0DA. I'm not sure what the differences are between the 0G and 0H, but I seem to recall seeing a post stating that they increased the intensity of the backlight on one version.

Yes, the last post was only about the batteries. The charger is great and I haven't noticed any problems with it. I did buy some cheap Chinese batteries - 12 AA 2700 maH and 8 AA 1200 maH for $6. The AA's wont work in any charger, even the C9000 in a break-in mode. I think I'll try to play around a bit and see if I can get any of them to work. I guess that these cheap no-name batteries are cheap and no-name for a reason.

The guy on eBay who sold me the charger is an authorized MAHA dealer and does sell a complete line of their chargers as well as the Powerex batteries as well.

John


----------



## krayzeemofo

wow, I just checked the seller 'new-bliss-tech' and it seems that his prices are actually on the high side atm:
http://shop.ebay.ca/merchant/new-bliss-tech_W0QQ_dmdZ1QQ_ipgZ50QQ_sopZ12


----------



## fireguy

Just checked the auction I bid on and it did say that it was a sale. Guess I got a good deal, then. I actually didn't check the prices on anything else, like batteries.


----------



## StandardBattery

krayzeemofo said:


> I must have missed it then, or perhaps my wording didn't convey what I meant, lol. Are the AAA cells *supposed* to sit at an angle with the positive side higher than the negative?
> 
> Thanks


The AAA cells sit totally flush in their slots. Maybe your cells are a little longer than standard and require a little extra push, or you're being too gentle. They do sort of 'snap' in, to make a solid low resistance connection.


----------



## chewy78

I have recently tried to cycle a pair 5yr old sanyo 600mah nicads for 3 cycles and my c9000 charger only showed 2 cycles? I charged at 600 mah and dischared them at 300mah. Anybody else have a problem like that? 
The number on the back is 0G0KA.


----------



## Black Rose

From what I've observed in my own cycle runs, the last cycle will not have a selectable cycle number. 

The data for the last cycle is displayed by default at the very end of the overall cycle run.

If you select the data for cycle 1, it will display and then it falls back to display the data for the last cycle again.


----------



## fireguy

fireguy said:


> Hi,
> Originally Posted by *krayzeemofo*
> 
> 
> _edit: I just noticed that you are located in Ontario, where did you get your C9000 and where do you normally get your battery/battery accessories? I ended getting mine from thomas-distributing, but was wondering if there was any place closer/in Canada other than paulsfinest._



I just came across a website for a store in the Hillcrest mall in Richmond Hill. they advertise 30% off the C9000 if you buy a Fenix L2D Q5 LED flashlight. Their website is 

http://www.j2ledflashlight.com/mahaenergy-mh-c9000-wizard-one.html

and they do have a link to CPF for the C9000. I couldn't find a price on their website, and I don't know anything about the store. Just FYI!


----------



## 45/70

j2led is a good guy. I've dealt with him before, about three years ago though. I doubt anything has changed. I'm pretty sure he's a member here, but it's been a while and I don't remember his handle.

Ah, just looked it up. j2ledflashlights, how appropriate! 

Dave


----------



## krayzeemofo

nice, if I'm ever in the area then I'll probably drop by. It'd be a bit of a drive just for batteries . I wish prices would be posted though.


----------



## krayzeemofo

oh, another question: do you guys leave the charger plugged in even when not in use?

Thanks


----------



## pobox1475

^ No. I put mine away in the travel pouch w/it's power supply.


----------



## Mr Happy

^ I've left it plugged in for days with no problem, but I do generally try to unplug things when not in use as a general safety precaution.


----------



## Eugene

I have two power strips for all my chargers. One has a couple chargers I use every couple days like my cell phone and bluetooth and one that has the chargers I use weekly like my razor and the c9000. I turn the strip on in the evening to charge something then off when done.


----------



## krayzeemofo

thanks for the replies


----------



## Black Rose

krayzeemofo said:


> oh, another question: do you guys leave the charger plugged in even when not in use?


I do on occasion, simply because the power bar it's plugged into is a PITA to get to.

I really need to address that.


----------



## wptski

I seen a story on TV stating that wall warts draw almost as much power when not in use compared to in use! I checked one but don't remember exactly how much it was but I was amazed! Anything that isn't buried behind furniture, I unplug when not in use.


----------



## Eugene

They don't waste that much but by the time you add up a half dozen it is wasteful. Thats why I consolidated all mine to one location and put them on the switched strips.


----------



## wptski

Eugene said:


> They don't waste that much but by the time you add up a half dozen it is wasteful. Thats why I consolidated all mine to one location and put them on the switched strips.


"Waste" is the key word here, why waste any? Just like leaving your PC ON 24/7! Dumb!!


----------



## Eugene

Actually most people do leave their pc on, thats when they run the virus scan and all that stuff. When I was at a job where I supported desktops 9 times our of 10 when people would complain about their system being slow it was because they turned it off at night so the virus scan had to run all morning when they turned it back on.
Even though I don't have to do a virus scan anymore I still run backups at night. My work laptop takes so long to boot or resume from suspend that I have to leave it on all the time too because when I'm on call I have to respond quickly and its running windows XP with only 2G of ram so it has to spend so much time swapping it can hardly keep up with me.


----------



## 45/70

wptski said:


> "Waste" is the key word here, why waste any? _*Just like leaving your PC ON 24/7! Dumb!!*_



Not really true, at least, not always.  A well built PC will run more hours MTBF, left on 24/7, than a PC that is turned on/off once per day. The most wear/damage occurs to a PC when it is starting up (hard drives, fans etc.) and, when the various chips (processor, chipset, memory etc.) heat up and cool down. Turning on/off more than once a day reduces the MTBF even more. Some may argue that turning a PC on, only when you're using it, and off when you're done, effectively increases the number of years/months the computer can be used. This may (but not necessarily) be true, however a well built PC running 24/7 will, generally, be obsolete before failure.

As for waste, yes, running a PC 24/7 may be considered wasteful. I would point out, that where I live here in Ohio, electricity has become the cheapest way to heat a home, unless you heat with wood and have a free supply. In this situation, a watt from a PC heats my home the same as a watt from my electric oil filled radiators. Therefore, the actual waste in the winter/heating months, is zero. The summer is a different story. It may be considered a waste then, but I usually have one running 24/7 then as well, as it is part of my business. I'll also add, that I run distributed computing projects, as well, so my PC's aren't just sitting around idling, when I'm not using them.

As for wall warts, by their design, they have components crammed into such a small area, that heat is a problem. Therefore, it's best to unplug/disconnect them when not in use. Most modems, routers, switches, KVMs, etc. that I've seen fail, really didn't. The failure of the wall wart is usually the cause.

OK, off topic. wptski, you made me do it! :naughty:

Dave


----------



## daj013

I just purchased this charger along with some Duracell 2650mah NiMH.
On the battery itself it states "Standard charge 270mA for 16h". 
Should I just put them on charge at 270mA or do a break in?
If I perform a break in, what set battery capacity should I select?

Thanks
David


----------



## Black Rose

General experience of forum users seems to indicate that the Duracell 2650 cells are crap and will not last long. 
Just type "Duracell 2650" in the Google search box at the top of the forum to see what others have to say about them.

If you haven't opened them yet, you might want to consider taking them back and getting some Duracell Pre-Charged or other cells.

If you have opened the cells already I would say you should do a discharge on the cells. 
A 500 mA discharge should be fine since they are likely already drained. 

Then do a break-in and set the capacity to 2600 mAh. 
The break-in mode puts more energy into the cells than they are labelled for anyway.


----------



## 45/70

daj013, do a break in and set the capacity as 2600. It's best in these situations to round the number down, so as to not exceed the 0.1 C limit.

Dave

Edit: Black beat me to it. Yes, a discharge first is also recommended.


----------



## jhellwig

Read the instructions. Also read the Maha Faq http://www.mahaenergy.com/store/mhc9000faq.asp .


270ma will end up being what the c9000 will charge at if you do a break in on the batteries.



Yall beat me to it.


----------



## 45/70

jhellwig said:


> 270ma will end up being what the c9000 will charge at if you do a break in on the batteries.



Actually, if you set the battery capacity at 2600, the C-9000 with do the break in charge at 260mA, which is below the 0.1 C maximum, as opposed to setting at 2700 which would charge at 270mA, which is over the 0.1 C maximum. 

Dave


----------



## jhellwig

That may be but Maha says that for odd capacity cells like 2650mAh and 2450Mah to go to the next hundred. Ie 2700mAh.


----------



## Black Rose

True, but Maha also says to put AA batteries into the charger positive end first, which can result in torn wrappers on the negative end


----------



## 45/70

jhellwig said:


> That may be but Maha says that for odd capacity cells like 2650mAh and 2450Mah to go to the next hundred. Ie 2700mAh.



Yeah, that may be true, and it probably doesn't make any difference, but a standard charge is 0.1C maximum.

As far as the Maha C-9000 manual goes, it's still the one for the very first C-9000's. Nobody's perfect!

Dave

Edit: Black, you're fast!


----------



## Black Rose

45/70 said:


> Edit: Black, you're fast!


Just have nothing better to do this afternoon since some parts I ordered have not arrived yet.

Otherwise I'd be wielding my soldering iron of terror against some unsuspecting flashlights


----------



## TONY M

Black Rose said:


> True, but Maha also says to put AA batteries into the charger positive end first, which can result in torn wrappers on the negative end


Very true this does indeed tear wrappers.  Thats "mahatalk".


----------



## Turbo DV8

I bought two of these just before Christmas for myself (in the spirit of receiving!) I have three BC-900's, and I wanted these Maha's for their ability to do a discharge capacity test without automatically recharging afterwards like the BC-900 does in discharge or refresh. In this respect, it satisfies, but on so many other levels, for me it is a step down from the BC-900's, not the least of which is some of the results are so clearly bogus that my units must be defective. I'll start with the unforgivable stuff first.


I started with sixteen brand new AAA Eneloops I bought along with the Maha. Experience has shown that Eneloop cell-to-cell voltages are extremely close out of the package. I ran a discharge at 500 mA. As soon as all first eight cells were inserted and began to discharge, I immediately noticed that the voltages under load ranged between 0.95 V - 1.24 V. Suspecting this was bogus, I put all eight immediately into the BC-900's at 500 mA discharge, and all eight voltages under that load began at 1.20 V + - 0.03 V and settled at about 1.17 V after two minutes. I put them back in the Maha's at 500 mA load discharge. Again the voltages were between 0.95 V and 1.24 V. First, notice how close the lowest one was to the 0.9 V discharge cut off voltage already, and fresh out of the package. After only a few minutes, the lowest one dipped below 0.9 V and the Maha said "DONE!" I immediately pulled this cell, which the Maha said was now dead, and put it on the BC-900 to continue discharge at 500 mA. The cell delivered 553 mAh on the BC-900 after the Maha said it was dead.


The problem as I see it is, there is some instability in my units in that the beginning indicated voltages under load are all over the place, even on cells that are known to be matched. After 20 minutes, all remaining seven voltages under load had stabilized between 1.04 V - 1.08 V (which, BTW, I know from running Eneloops on the BC-900 is much lower than actual voltage under that load). What I observed during 20 minutes is that the lower indicated voltages came up under load (except the lowest, which terminated before it's voltage had a chance to rise) and the higher indicated voltages came down under load, all to meet somewhere in the middle at 1.04-1.08 V. Now, I don't know about anyone else, but I've not known a cell under load to rise in voltage! All seven other cells discharging on the Maha did ultimately yield between 514 - 532 mAh. I ran the above tests on the remaining eight cells, and again the start voltages were all over the board (and inaccurately low) at the beginning of discharge, then some voltages came up over 20 minutes, and some came down, all to meet at a nice uniform figure in the middle. This is not normal! Incidentally, after charging all sixteen cells on the BC-900's, resting for one hour, and discharging on the BC-900, all sixteen cells delivered between 830 - 879 mAh, so I know the cells are not the cause of the strange results on the Maha.


So at this point, I was very unhappy about the inconsistent and strange results the Maha was giving me. So I began some tests on eight known good AA Eneloops. I ran more detailed tests and kept even more detailed records than before. I ran the following tests:

1 - (BC900/BC900): Charge @ 500 mA on BC900, rest one hour immediately after termination, discharge @ 500 mA on BC900.

2 - (BC900/Maha): Charge @ 500 mA on BC900, rest one hour immediately after termination, discharge @ 500 mA on Maha.

3 - (Maha/Maha):
(Cells 1-4): Charge @ 500 mA on Maha (no "top off"), rest one hour, then discharge @ 500 mA on Maha.

(Cells 5-8): Charge @ 500 mA on Maha (plus 2 hours "top off"), rest one hour, then discharge @ 500 mA on Maha.

4 - (Maha/BC900):
(Cells 1-4): Charge @ 500 mA on Maha (no "top off"), rest one hour, then discharge @ 500 mA on BC-900.

(Cells 5-8): Charge @ 500 mA on Maha (plus 2 hours "top off"), rest one hour, then discharge @ 500 mA on BC-900.


As you can see, the above tests would answer a few questions. One, how much more capacity does one get from the batteries with and without the two hour "top off" charge on the Maha. Second, to compare remaining capacities as indicated on Maha vs. BC-900. Third, to compare how fully the Maha charges compared to the BC-900. I think I hit all possible combinations with the above tests.


I won't bore with all the details, but will hit upon the notables. First, on Maha discharges, I noted the same strange occurrence of initial voltages varying widely, then over time some voltages rising and some falling under load. For cells that happen to fall at the low end, this may cause the Maha to finish discharge even while up to 75% actual capacity remains (as determined on the BC-900 after "DONE" on the Maha). Finally, as with the AAA cell tests, one of the Maha's had another brain fart during the AA tests. After the BC-900 discharge on test # 4, I put all eight cells in the Maha's to charge @ 500 mA. One cell "terminated" at 1.37 volts with only 978 mAh "into" the cell. The remaining seven continued to completion two hours later. The one which prematurely terminated was immediately placed into the BC-900 @ 500 mA, and it continued charging for about another two hours before terminating. Why did the Maha terminate the charge on that one cell only half way through charging?


So, I'm just throwing this all out for comments and thoughts. From my tests, I learned that if I expect to get discharge capacities to agree between Maha and BC-900, the Maha does need that at least 2 hour top-off after "DONE" (in which case, the results are in close agreement). I learned that the Maha needs an even bigger display, as when the Maha says "DONE" it should really display "Maybe DONE, Maybe NOT." Or, "Nebulously DONE." Finally, in addition to finishing discharges before the cell is actually discharged, the Maha also terminated a charge only half way through the charge process. Why? Granted, both cases of gross misconduct cited occurred on the same individual Maha charger, but I still see the voltage swings occurring on both chargers, and I feel it is only a matter of time before both chargers will indicate "DONE" before it is time. I wanted to love these, but I just do not trust them, so they will be going back. But I'll wait until I hear any thoughts on this. Anybody else had any of these unusual occurrences happen to them on their Maha's?


----------



## jhellwig

Mybe you just got a bumm charger. Was it both or just one? Contact Maha and see what they say. 

Maybe you bc900's are wrong. Maybe the batteries are bad. There are just to many things to be wrong.


----------



## Black Rose

I don't have a BC900 to compare against, but I'll toss a set of 4 AA Eneloops on the C9000 to discharge and watch the voltages and see what it says.

BTW, what is the "serial number" of your C9000's?

EDIT #1: Immediately after putting the 4 Eneloops in 500 mA discharge mode, all 4 are showing 1.21 volts.

EDIT #2: After 1 hour in 500 mA discharge mode, all 4 Eneloops are now showing 1.17 volts, so they are dropping at similar rates across all channels.


----------



## Mr Happy

Turbo DV8 said:


> Anybody else had any of these unusual occurrences happen to them on their Maha's?


Your results are very strange and perplexing. I wonder if your units are faulty somehow, or if you are getting a bad connection with the cells?

I only have one C9000, but I have never seen it do the kind of things you describe. If I discharge 4 balanced Eneloops I always see discharge voltages that start out the same and which match to within +/- 0.01 V or so during the beginning and main part of the discharge. They vary a bit more at the very end of the discharge when all the cells are racing down towards 0.9 V, but not at the beginning.

Likewise, I have never seen a premature end of charge (with AA cells). With Eneloops the charge always terminates at the high voltage threshold of 1.47 V (which is why you need the top-off for a full charge). This failure to charge all the way to the -dV signal could be considered a shortcoming of the charger, but it is quite systematic and repeatable, and not in any way random.

The C9000 is very sensitive to the electrical connection though, which is why I wonder about connection problems. The slightest contact problem will cause the charger to misbehave. For instance, the connector design for AAA cells is not very good, and I find I need to insert AAA cells very carefully to ensure they charge and discharge properly. Occasionally I have had AAA cells abort part way through, especially ones where the wrapper overlaps the negative end. This is undeniably another shortcoming of the C9000. Maha really should design the AAA cell contacts better.

Overall though, my unit has been consistent and reliable. Since you are having so many problems, I think it would be worth contacting Maha for support and warranty service before giving up entirely.

[Edit: I've just remembered some people have reported contact problems with AA cells, where the positive button is too short to make good contact with the metal contact spring. The shoulder of the battery holds it just too far away from the contact. I think some people have described shaving away a bit of the plastic around the charger contact to bring the cell closer to the spring, or bending the spring slightly so that it is further forward. Some of the older Eneloops in particular have had this problem due to their shorter button height.]


----------



## SilverFox

Hello Turbo DV8,

If I may offer some comments...

You started with brand new cells and began to discharge them. Do you realize that the BC-900 and C9000 use different pulse currents for discharge? I believe the BC-900 uses 500 mA and the C9000 uses 1000 mA.

The cell voltages under these different loads will be different. If you check the NiMh shoot out thread you can see the voltage differences with the Eneloop AAA cells at 500 mA and 1000 mA of discharge current.

One of the down sides to the low self discharge chemistry is that when the cell is stored for an extended period of time, its internal resistance increases. It is not uncommon to see voltages rise during discharging as a result of this.

Once again the higher current pulses of the C9000 will amplify the higher internal resistance of the cell. This is evident by the cell quickly dropping to 0.9 volts and still having some capacity left when discharged at a lower rate.

The next issue I have is that it is not representative to run tests on cells that haven't been broken in and have a few cycles on them. New cells often false peak and end up showing strange behavior during the first couple of charge/discharge cycles. We have been very fortunate with the Eneloop cells, but the longer they sit on the shelf the more they behave like all of the other NiMh cells. By the way, is there a date code on the cells? Also, what was the open circuit voltage of the cells before you started testing them?

The standard procedure when you run into unexpected behavior with NiMh cells is to run a "standard charge" and "standard discharge" cycle on them, followed by a couple of 0.5C charge/discharge cycles. Now you have cells that are properly broken in and you can run tests to determine if you still have strange behavior.

I might add that "out of the box" performance is interesting, especially with the low self discharge cells, but it is not representative of cell performance. It often takes more time to prepare the cells for testing than it does to actually run the tests. I am constantly testing cells and battery packs. In order to maintain consistency between tests I always follow a break in procedure. Sometimes there is no difference between the initial results and the results after breaking in, but when the cells are somewhat aged, the break in procedure seems to level the playing field and brings the cells back up to optimum performance.

When comparing the performance of the two chargers at the end of the charge (without the top off charge), keep in mind that the BC-900 terminates at 1.52 volts and the C9000 terminates at 1.47 volts. With AA cells and charging at 1000 mA, the C9000 beat out the BC-900 by a small amount.

OK, where do you go from here...

I would suggest that you discharge your new cells at 400 mA, then do a Break-In cycle on them in the C9000. Once you have completed that, do 3 - 5 charge/discharge cycles charging and discharging at 0.5C. Now your cells are ready for testing, and you can proceed to run your comparisons between the BC-900 and the C9000.

Tom


----------



## 45/70

I have some experience with both the C-9000 and the BC-900. One thing that comes to mind about Turbo DV8's discharge anomalies, is the fact that the C-9000 discharges @ 1 Amp, regardless of the discharge setting, because the C-9000 uses PWM. I'm not certain, but I believe the BC-900 uses constant current during discharge. Perhaps this is part of the reason why the results were so different?

As for the other noted problems Turbo DV8 experienced, I'm not too sure. Perhaps Mr H's suggestion of poor contact is the culprit.

My biggest complaint about the C-9000 would be the poor way it handles the internal resistance test of AAA's. AAA NiMH cells have a higher internal resistance than AA's when they are new. After some normal wear, they of course develop even higher internal resistance, causing the C-9000 to reject them prematurely. It seems like Maha could have made some arrangement to handle AAA's better in this regard.

There are of course, some other minor inconveniences about the C-9000, like the 2 hour "top off" charge for example, but using it as an analyzer, they're really not that much of a problem, for me.

I've mentioned before, I think the BC-900 is really, in a lot of ways, a better charger. For battery maintenance etc. though, the C-9000 is hard to beat.

Dave

Humm, I see Tom has beat me. I'm just too slow. :sigh:


----------



## Turbo DV8

Thanks for all the thoughts. When I add it all up, I guess the Maha is just not for me. 



> One of the down sides to the low self discharge chemistry is that when the cell is stored for an extended period of time, its internal resistance increases. _It is not uncommon to see voltages rise during discharging as a result of this._


 
I did not know that! Mostly because I have _never _seen voltage under load go up on my BC-900's... new cells or old.



> Once again the higher current pulses of the C9000 will amplify the higher internal resistance of the cell. This is evident by the cell quickly dropping to 0.9 volts and still having some capacity left when discharged at a lower rate.


 
That makes plenty of sense. But on the other hand, I am left with the fact that my BC-900's never ended a discharge prematurely on new cells, even Eneloops that were manufactured two years earlier. I definitely hear what you're saying about the Maha current pulses at 1000 mA instead of 500 mA. But in my mind, I don't know, I guess my thoughts are if I set the discharge current on both machines at 500 mA, and one rejects cells that are good and the other doesn't, well then I sort of consider that a defective design. 




> The next issue I have is that it is not representative to run tests on cells that haven't been broken in and have a few cycles on them. The longer they sit on the shelf the more they behave like all of the other NiMh cells. Sometimes there is no difference between the initial results and the results after breaking in, but when the cells are somewhat aged, the break in procedure seems to level the playing field and brings the cells back up to optimum performance. By the way, is there a date code on the cells?


 
The new AAA cells were all dated April 2008. Not certain I consider that aged to imperfection. Also, I may not have made it clear, but keep in mind that all the tests on the eight AA cells were done on seasoned, known good cells, including the one that prematurely terminated only half way through the charge. 




> I would suggest that you discharge your new cells at 400 mA, then do a Break-In cycle on them in the C9000. Once you have completed that, do 3 - 5 charge/discharge cycles charging and discharging at 0.5C. Now your cells are ready for testing, and you can proceed to run your comparisons between the BC-900 and the C9000.


 
I could definitely do that, but you know, I'm really cringing here with the notion that one would have to discharge at this rate, do a break-in cycle, then do 3-5 charge/discharge cycles @ 0.5C before the cells are _even ready_ for testing. I mean, that's pretty nebulous. Don't take this as being smart-***, but how do I know they're "ready" after 3-5 cycles? Why not 5-8 cycles? I am not trying to be rude, but really, I can't see the necessity in all that ritualistic voodoo when I know the BC-900 would run the tests with aplomb the first time, every time, no questions asked, and no prior pomp and circumstance needed. 

Then, I'm still left with that known-good, seasoned AA cell which the Maha decided was done charging at 1.37 volts/978 mAh. The point was made about the contacts having a problem with AAA cells with wrappers extending onto the negative contact, or some AA cells positive nipples not making good contact, suggestions to shave the plastic of the charger, bending the spring... :shakehead Come on! What can contacting Maha support and warranty service do for a defective design? What can they do for me to make their units less picky about internal resistance, or whatever causes their charger to stumble on a simple task that my BC-900's have performed hundreds of times for me with nary a hiccup? Please don't anybody take my tongue-in-cheek comments as being anything but appreciative of your comments and suggestions, but you can sense my amazement at how much forgiveness I sense the Maha receives here!

Again, thanks for the suggestions, and also the education. I did learn some things, and as usual, I can blame SilverFox for some of that! But, taking all into consideration, I just don't trust the Maha when, on the other hand, the BC-900 never disappoints...

...until it melts down. :devil:


----------



## Mr Happy

I still feel you have somehow ended up with two faulty samples of the charger. I hear your doubts about contacting Maha for warranty support if the basic design is faulty, but unless people do complain Maha will not get the necessary customer feedback to fix it.

There is something I can do to give you a reference point. I have an unopened pack of Duracell Pre-Charged AAA that I bought a few months ago. Tomorrow morning I will measure the open circuit voltages and then put them on a discharge at 500 mA. I will make a note of the voltages during discharge and the final capacity readings and let you know what happens.


----------



## Black Rose

Turbo DV8 said:


> But, taking all into consideration, I just don't trust the Maha when, on the other hand, *the BC-900 never disappoints...*
> 
> *...until it melts down*. :devil:


...and that's the #1 reason why I can't trust the LaCrosse BC-900 and don't have one.

If it didn't have that nasty feature of possibly turning into a puddle of melted plastic, I'd have one.


----------



## SilverFox

Hello Turbo DV8,

I agree with you. It seems the best thing for you to do is to send the C9000 chargers back...

I still think that what you observed has everything to do with the cells and does not indicate problems with the chargers. The reason I hold this position is because I have observed the very same things with many different cells (including Eneloop cells) and it is not unusual for a charger to terminate the charge on a false termination signal. 

I have observed missed terminations on all of the chargers I have used, including my Schulze and my BC-900. Newer cells will false peak giving an incomplete charge and older cells will never peak resulting in over charging, and sometimes visa versa. Take the same cell, after it did not terminate properly, and it will do fine on the next charge. I don't know why, it just happens from time to time. Fortunately, it is not a regular occurrence.

What you refer to as "ritualistic voodoo," I call "conditioning."

You described unusual things happening during charging. Since I have observed those same things before, and have identified them as being cell issues rather than charger issues (in most cases), I gave you instructions on how to condition your cells. After conditioning, you could run the tests again eliminating the cells as a variable. This involves a lot of time and effort, and I can fully understand why it wouldn't be a satisfactory solution for you.

However, I wonder what your comments would have been if you had done the charger comparison with "conditioned" cells and the understanding that missed terminations are simply a fact of charging...

At any rate, when you do a "standard charge" and "standard discharge" you get a capacity for the cell. When you run the 3 - 5 cycles, you compare your discharge results with those obtained from the "standard discharge." You are looking for similar results, and know that the cells are "ready" when the the results stabilize.

I might also point out that Sanyo, the manufacturer of the Eneloop cells, recommends charging at 0.5-1.0C. They give performance curves after charging the cells at 1C. They recommend 1C charging when using a change in cell temperature to terminate the charge, or when using -dV to terminate. Since both the BC-900 and the C9000 use -dV, you may have observed different results had you conducted your tests following Sanyo's recommendations.

If I may offer a suggestion... Before you send the C9000 units back you may want to consider doing a "Break-In" cycle on your "seasoned" AA cells to "condition" them...  

AND, I sincerely hope that your BC-900 never melts down.

Tom


----------



## Mr Happy

OK, here are the results of my test with the four "Duraloop" AAA cells.

Open circuit volts
1.299 1.300 1.298 1.300

First I tried a discharge at 500 mA.
volts after one minute
1.09 Done Done 1.10

Clearly these cells were in no condition for a 500 mA discharge. The voltage plummeted and the two middle cells stopped discharging straight away.

I pulled the cells and switched to a discharge at 200 mA.
This proceeded in a stable manner:
volts after 3 mins
1.12 1.14 1.09 1.11
volts after 15 mins
1.12 1.13 1.08 1.10
volts after 45 mins
1.13 1.13 1.09 1.11
volts after 90 mins
1.13 1.13 1.09 1.11

It looks like the 3rd cell is a bit weak compared to the other three. The discharge continues, and I will report the recorded capacities when it finishes.

I think these cells need a bit of conditioning as advised by SilverFox. I hope the 3rd cell will wake up a bit after a break-in. Once I have exercised them a bit, I will try again to see if they can manage a 500 mA discharge.

Perhaps we can say that the C9000 is a very rigorous and sensitive instrument? It would be a good thing if it can pick out weak and poorly conditioned cells that you otherwise might not suspect as being bad.

Update #1

The discharge completed and this was the state of charge recorded:
mAh at end of discharge
564 585 575 574
volts after resting
1.21 1.20 1.21 1.20

The readings between cells are more or less evenly balanced, with an average charge 72% of the label capacity.

I am now putting them on a break-in charge set at 800 mAh:
volts at start of break-in charge
1.26 1.26 1.26 1.26


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## SilverFox

Hello Mr Happy,

If I am reading your results correctly... it appears that you also saw a couple of cases of voltage increase during the discharge.

I will go a step further. The C9000 not only is aggressive at weeding out marginal cells, but it also offers the functions needed to give the cell every chance of recovering and returning to optimum performance.

Tom

Edit, to add: While the C9000 offers may advanced features and does a good job, it is far from being perfect. I still find myself "pushing" it into more advanced functions. Perhaps we can hope for an even more advanced charger from Maha in the future...


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## Turbo DV8

SilverFox said:


> What you refer to as "ritualistic voodoo," I call "conditioning."


 
Nope, it's right there on my displays:

*MODE*
CHARGE
REFRESH/ANALYZE
BREAK-IN
DISCHG
CYCLE
RITUALISTIC VOODOO


----------



## pobox1475

I recently opened a 4-pack of Monster Power 1800's that I purchased about 3-4 years ago. I have run two back-to-back break in cycles after first discharging them. The results after each were an average of 1280 mAh. Can anything be done to improve their capacity? I know the rating of most cells is a little optimistic, but -30% seems rather poor.


----------



## SilverFox

Hello Turbo DV8,



Tom


----------



## SilverFox

Hello Pobox,

I have seen off brand cells in the 1400 - 1800 mAh range that come in at about 70% of their labeled capacity when new.

The key to your cells health is the voltage under load. If you watch the discharge, note the voltage when you are at 600 mAh of discharge. This is about half way through the discharge. Under a 500 mA discharge load, on the C9000, you should see voltages at 1.2 or 1.19 volts. If your voltage is much below that, the cells are crap.

Tom


----------



## Mr Happy

pobox1475 said:


> I recently opened a 4-pack of Monster Power 1800's the I purchased about 3-4 years ago. I have run two back-to-back break in cycles after first discharging them. The results after each were an average of 1280 mAh. Can anything be done to improve their capacity? I know the rating of most cells is a little optimistic, but -30% seems rather poor.


There may not be much you can do to rescue them. Regular (non-LSD) NiMH cells do not have a long shelf life. In an ideal world they should be used and refreshed within a year of manufacture to keep them healthy. After 3-4 years unopened and untouched, they may have suffered chemical degradation that cannot be reversed.

For future reference if you have other NiMH cells, make a note on the calendar to refresh them every six months if they are not being cycled through regular use.


----------



## TakeTheActive

*Am I Interpreting This Correctly?*



SilverFox said:


> ...*The key to your cells health is the voltage under load.* If you watch the discharge, note the voltage when you are at *600 mAh* of discharge. This is about half way through the discharge. Under a *500 mA* discharge load, on the C9000, you should see voltages at 1.2 or 1.19 volts. If your voltage is much below that, the cells are crap...


I'm going to re-word your post to confirm that I'm interpreting it correctly:

If you monitor the discharge process, note the voltage when you are at the 0.5C point (i.e. 1000mAh for 2000mAh cells; *640mAh for 1280mAh cells;* 350mAh for 700mAh cells; etc...). Under a 0.4C discharge load (i.e. 800mA for 2000mAh cells; *512mA for 1280mAh cells;* 280mA for 700mAh cells; etc...) on the C9000, you should see voltages at 1.2 or 1.19 volts. If your voltage is much below that, the cells are crap...



SilverFox said:


> ...I have seen off brand cells in the 1400 - 1800 mAh range that come in at about 70% of their labeled capacity when new...


Thus, to determine "crap cells":
For NEW off-brand cells, after 1 'Break-In' cycle and 3-5 'Refresh & Analyze' cycles, IGNORE the capacity printed on the cells and use the CALCULATED capacity from the C9000 for the above "crap" determination.
.
For AGED brand-name cells, use the capacity printed on the cells.
- Another indicator is when the CALCULATED capacity from the C9000 is below 80% of the capacity printed on the cells.


----------



## SilverFox

*Re: Am I Interpreting This Correctly?*

Hello TakeTheActive,

The 1.2 volts under load is specifically for AA cells at or under 2000 mAh capacity. Cells of higher capacity tend to have higher internal resistance and that causes the voltage to drop a little more.

Technically, this is called "mid point voltage." As you have correctly interpreted, this is the voltage half way through the discharge.

I referenced a 500 mA discharge current because I happen to have data on that rate. This is not necessarily a 0.4C rate, its just 500 mA, regardless of the cells actual capacity.

Crap cells are defined as cells that:

Have less than 80% of their initial capacity. Sometimes the labeled capacity is close to correct, other times it is simply an "optimistic guess." 

When you initially get new cells the first thing you should do is to check their voltages. Cells that are above 1.0 volts can be given a standard charge and the capacity from a standard discharge can be used as a baseline. These cells are generally in good condition.

Cells that arrive below 1.0 volts are suspect. Sometimes they come back and other times they don't. It may take several standard charges and discharges to bring them up to their optimum capacity, and they are suspect for having higher internal resistance, and developing higher rates of self discharge.

The next thing to look at is voltage under load. This is where the mid point voltage comes in. When comparing cells it is good to standardize on a discharge rate, but with varying capacities, this can be a little misleading. I, informally, look at how the cell performs at 500 mA, but formally I look at two different rates. One is 0.5C and the other is 1.0C. If the application involves high currents, I will adjust the discharge current to check the voltage under the load the cell will be seeing, but still formalize on 1.0C voltage under load performance.

The next thing that qualifies a cell as a crap cells is its self discharge rate. 

The final thing is its general condition. No rust spots, dents, torn (or melted) label, etc.

Keep in mind that there are others who are less picky about their cells that use some different numbers. For example, some people keep the cell until it is simple below 60% of the labeled capacity, and don't pay attention to mid point voltage. Others simply keep moving the cell to less demanding applications and finally into the drawer for those "just in case a disaster happens" moments. 

I am not sure if one way of looking at this is right or wrong, but I know that my way is better.  In an emergency, I know that I can grab the cells from my remote thermometer or remote control, and they will work just fine in my high current draw flashlight. Also, if anyone in the household besides me grabs cells to use, I know that they will be vibrant and will give good performance.

Tom


----------



## Turbo DV8

*Re: Am I Interpreting This Correctly?*



SilverFox said:


> Hello TakeTheActive,
> 
> The 1.2 volts under load is specifically for AA cells at or under 2000 mAh capacity.


 
What would you suggest the minimum mid-point voltage be for the 800 mAh AAA cells, and taken at what discharge current?


----------



## SilverFox

*Re: Am I Interpreting This Correctly?*

Hello Turbo DV8,

Using the C9000 and discharging at 400 mA, you should see voltages of 1.16 or higher. Very good cells will be at 1.17 or 1.18 volts. Once they drop below 1.15, they are well on their way to being crap cells.

The reason for the lower voltages is the higher internal resistance of AAA cells.

Tom


----------



## 45/70

Turbo DV8 said:


> What would you suggest the minimum mid-point voltage be for the 800 mAh AAA cells, and taken at what discharge current?




I sorta look at all this in reverse. The "ideal" voltage to be maintained under load, is the spec voltage for a NiMH cell, or about 1.2 Volts (or above). So, what you are looking for is the maximum current at which the cell (regardless of size or capacity) can maintain 1.2 Volts.

The 1.2 Volt level may be variable to some extent, depending on your particular application, but 1.2 Volts is a good benchmark, as it is a "standard". As I said, this is somewhat dependent on the device you're using. In a hotwire, for example, it is important to keep the cell voltages, under load, at or above 1.2 Volts per cell for best performance. On the other hand, an LED light with a decent boost circuit, may still work well with a cell or cells that won't hold their voltage at 1.2 Volts, at the required current. Still, the cells that are incapable of holding their voltage up as well are not, obviously, as fit for the job, and may better be relegated to use in lower drain devices.

This is my method of determining what constitutes "crap cells". YMMV.

Dave


----------



## Turbo DV8

> When you do a "standard charge" and "standard discharge" you get a capacity for the cell. When you run the 3 - 5 cycles, you compare your discharge results with those obtained from the "standard discharge."


 
OK, so after all my hemming and hawing and chomping at the bit, I'm finally feeling broken, so I am actually running eight of the new AAA Eneloops on break-in, which is what I assume you mean by "standard charge" and "standard discharge". Thing is, now that it is nearing the latter half of the second charge, I notice the display shows the current "into" the cell during the charge, not the capacity obtained from the 0.2C discharge. Will the discharge capacity reading reappear when the break-in is "DONE"?


----------



## Mr Happy

Turbo DV8 said:


> Will the discharge capacity reading reappear when the break-in is "DONE"?


Yes 

Incidentally, my experiment with the Duracell AAA cells is still continuing. I'll post another update soon.


----------



## fireguy

Turbo DV8 said:


> OK, so after all my hemming and hawing and chomping at the bit, I'm finally feeling broken, so I am actually running eight of the new AAA Eneloops on break-in, which is what I assume you mean by "standard charge" and "standard discharge". Thing is, now that it is nearing the latter half of the second charge, I notice the display shows the current "into" the cell during the charge, not the capacity obtained from the 0.2C discharge. Will the discharge capacity reading reappear when the break-in is "DONE"?



If you're doing multiple cycles of charge/discharge, you can press the up or down arrow key to see the results of previous cycles, just not the current cycle that is resting. 

As for the break-in, you have to wait until the end unless you watch it after the discharge cycle. At this point it shows you what was discharged and you know the results without waiting for the rest and charge (18 hrs). I believe, if memory serves me correctly, the discharge amount is available through the entire rest cycle, it just disappears once the charge operation has been started.


----------



## Mr Happy

OK, here's my next update on the Duracell AAA cells that were behaving so poorly out of the package (see post #229).

After the break-in cycle the reported capacities were 797 807 805 804 mAh. These compare quite favorably with the 800 mAh label capacity.

The break-in charge finished this morning, and I have this evening put them on another 200 mA discharge to compare with the first one. Here are the results so far (it is not finished yet):

volts after 1 min
1.28 1.28 1.27 1.28
volts after 45 mins (130 mAh)
1.19 1.19 1.19 1.19
volts after 90 mins (270 mAh)
1.17 1.18 1.18 1.18
volts after 133 mins (400 mAh)
1.17 1.17 1.17 1.17

As can be seen the voltages are higher and are much more evenly balanced between the cells now. Once this discharge finishes I will cycle them a couple of times at a faster rate and then make another attempt at the 500 mA discharge that they could not sustain to begin with. I am quite interested to see if they can do it at all since I have little experience with AAA cells compared to the AA variety.


----------



## Turbo DV8

*Re: Am I Interpreting This Correctly?*

Let me reiterate up to this point. Let's take the first eight of my brand new AAA Eneloops cells manufactured in April 2008. First I discharged them on the Maha at 500 mA. Then I charged them and discharged them again at 300 mA on the Maha, and got the following mAh capacities:

763-760-750-744-769-762-773-752

(An additional charge and discharge on the BC900 gave somewhat higher figures between 849-879 mAh's, which I undestand is to be expected.)

Then it was suggested to run a break-in. At the end of break-in, which discharged at only 160 mA, the capacities were as follows:

805-785-791-785-802-779-786-786

After the end of break-in, I discharged again at 400 mA to obtain the mid-point voltages, which were as follows (at one hour):

1.13-1.11-1.09-1.13-1.15-1.15-1.13-1.13



SilverFox said:


> Using the C9000 and discharging at 400 mA, you should see voltages of 1.16 or higher. Very good cells will be at 1.17 or 1.18 volts. Once they drop below 1.15, they are well on their way to being crap cells.


 
So, I have eight brand new Eneloops of April 2008 manufacture. They have been cycled at least three times total, plus a break-in. According to the above suggested guideline, at least 75% of my brand new Eneloops are "well on their way to being crap cells." Hmmm... man, I gotta dump these Eneloop crap! 

I think my cells are fine and dandy, thank you very much. I stand by my first observation. My Maha's are reading voltages artifically low, which, among other things, can cause the Maha to prematurely terminate a discharge even with plenty of capacity under load remaining. I could now run another 3-5 cycles, but would that prove anything after already having several cycles on them, and already seemingly well balanced?


The end of my 30 day return period is approaching...


----------



## Mr Happy

My 200 mA discharge has finished now. Capacities were 776 787 786 785 mAh (the cells had rested for several hours after charging).

I'm going to cycle them a bit and then do a 400 mA discharge with my C9000 to give you a comparison to work with. I should have that result tomorrow. I'm learning here myself as I have not done this exercise before with AAA cells.


----------



## SilverFox

Hello Turbo DV8,

Very interesting...

I have a set of 4 AAA Eneloop cells that I use in my camera flash. The flash doesn't get much use normally, but when I need it I work the heck out of it.

I had charged the cells up just before Christmas. I pulled them out and ran a discharge at 400 mA on the C9000. 

60 minutes into the discharge I observed these voltages.

1.14, 1.15, 1.04, 1.05.

These cells are from the original release in Japan and are about 3 years old. It looks like at least a couple of them are headed to be crap cells.

I then charged them and ran another discharge at 400 mA. This time I observed the following voltages after 60 minutes of discharge.

1.18, 1.16, 1.14, 1.14.

I now have 2 cells that are good, by my definition, and 2 that are showing great improvement. One more charge/discharge cycle should bring them back to good performance.

These are my most abused cells. I don't use my flash for months, then suddenly need to use it all the time for a day or two, then it goes back in storage. I usually try to exercise my cells with a charge/discharge cycle every 30 days. I have not done this with these cells and it shows. I will change that and include these in my monthly exercise program.

By the way, at the end of the initial discharge I observed the voltage bounce between 0.95 volts and 1.02 volts several times on the cells that showed the lower voltage under load. The other cells just saw a steady decrease in voltage and did not jump around.

We still haven't determined if the problem is with your cells or your charger. Your 2008 cells are behaving similar to my 2006 cells that have basically been in extended storage. Do you happen to have any other AAA NiMh cells? If you do, you could run a test on them and compare.

Who did you get your chargers from? I would be happy to call them and see if I could get an extension on your 30 day return so we could figure this out.

Tom


----------



## Mr Happy

Here are my comparison results, continuing the test on a new set of 4 AAA Duracell pre-charged from earlier posts.

After the 200 mA discharge in post #246 I gave them 3 cycles of 400 mA charge/400 mA discharge. The last 400 mA discharge has just finished.

For each of the cells, these are the 400 mA discharge readings:

cell #1: 787, 787, 786 mAh
cell #2: 800, 799, 797 mAh
cell #3: 796, 795, 793 mAh
cell #4: 796, 795, 794 mAh

I noted the voltages at the 400 mAh point of the last discharge (that was about 66 minutes). They were

1.18, 1.18, 1.17, 1.18

If I had recorded them at exactly 60 minutes the third cell would also have been 1.18. It dipped down to 1.17 just before I noted the reading.

My feeling is that there is a good degree of consistency in successive tests with my sample of the C9000, and also good consistency between these four cells.

I would also wonder, as SilverFox suggested, if you have some other AAA cells from a different source that you could do a comparison test with? It does seem somehow that your samples of the C9000 are not delivering the results that would be expected.


----------



## Turbo DV8

Mr Happy said:


> I would also wonder, as SilverFox suggested, if you have some other AAA cells from a different source that you could do a comparison test with? It does seem somehow that your samples of the C9000 are not delivering the results that would be expected.


 
Edited for clarity: the following tests were performed on the new AAA Eneloops.

After break-in, I did another 400 mA discharge, followed by two more cycles. Then I halted the process, as they had plenty of cycles on them already, and there was no appreciable increase. The discharge and two cycles rendered the following capacities:

786-767-768-766-781-763-769-765
790-774-777-769-786-767-774-770
790-776-779-770-786-767-775-770

Then for fun, I charged them at 300 mA plus 2 hours top-off, then discharged on the BC-900 @ 350 mA for 400 mAh, then discharged the remainder on the Maha @ 400 mA. The mid-point voltages as shown on the BC-900 at 400 mAh discharge were:

1.19-1.19-1.18-1.19-1.18-1.18-1.19-1.18

After immediately pulling them from the BC-900 and inserting into the Maha @ 400 mA drain, after a minute of settling, the "new" mid-point voltages as shown on the Maha were:

1.14-1.13-1.12-1.15-1.14-1.14-1.15-1.06

Everything's quite a bit lower, and that last one is an example of exactly the strange behavior I originally noted.

Finally, for kicks, I took the sum of the initial 400 mAh BC-900 discharge and the remaining Maha discharge capacities:

400-400-400-400-400-400-400-400
+419-402-410-396-408-391-401-397
819-802-810-796-808-791-801-797

And to compare to the final Maha cycle capacities earlier:

790-776-779-770-786-767-775-770

All within 30 mAh of each other between Maha-only discharge and half-and-half. Not bad.



> Who did you get your chargers from? I would be happy to call them and see if I could get an extension on your 30 day return so we could figure this out.


 
Well, heck, SilverFox, if you have connections, let's just make it a lifetime warranty!  (Thomas Distributing... )

If I were to try another set of AAA cells, should I try with older Hybrids or older Eneloops, both almost a couple years old by now?


----------



## Chase2b

I am sure I know the answer to this question, but have to ask it anyway.

If I choose a certain cycle, i.e analyze/refresh and after approx. 12 hours (still in charge mode), I decide to cancel the rest of the cycle and just want to pull the batteries out. Does just cancelling the cycle by unplugging hurt the charger in any way? Can the charger be damaged?


----------



## Mr Happy

The answer is what you think it is.

But in fact you don't even have to unplug the charger. Just removing a battery from a slot will reset that slot ready for a new program.


----------



## SilverFox

Hello Turbo DV8,

After another charge/discharge cycle, my cells ended up with mid point voltages of

1.18, 1.17, 1.17, 1.17.

I still think the problem you are seeing has to do with your cells. I think those Eneloop AAA cells should show a mid point voltage of above 1.2 volts on the BC-900.

If you have some other Eneloop AAA cells, they would be good to confirm what we are seeing.

I will contact Thomas Distributing and see if I can get a small extension on your 30 day return. No promises, but I would really like to get to the bottom of this.

Tom


----------



## Mr Happy

Here's a final test on my Duracell AAA cells. I've been thinking about a 6AAA cell hotwire, and I started to wonder if AAA cells were up to it. To find out, I discharged the cells that were charged yesterday at 1 amp to see how they stood up to the load.

This also has a bearing on the thought that the C9000 might show lower discharge voltages because it uses a pulsed 1 A discharge current under PWM. No PWM here, it is a flat out 1000 mA.

Without further ado, here is the discharge profile:



Code:


1000 mA discharge of Duracell white top AAA cells
Cell    |  #1    #2    #3    #4
--------+--------------------------
100 mAh | 1.19  1.19  1.18  1.18 V
200 mAh | 1.18  1.18  1.17  1.17 V
300 mAh | 1.18  1.17  1.17  1.17 V
400 mAh | 1.17  1.17  1.16  1.16 V
500 mAh | 1.16  1.16  1.16  1.15 V
600 mAh | 1.14  1.14  1.13  1.14 V
700 mAh | 1.09  1.10  1.09  1.09 V
--------+--------------------------
Totals  |  763   778   771   775 mAh

The cells have held up remarkably well it seems (look back to post #229 where they collapsed and died the first time I tried a 500 mA discharge on them).

I'm beginning to wonder Turbo DV8, the same as SilverFox, if it is your cells that are misbehaving?


----------



## SilverFox

Hello Turbo DV8,

I contacted Thomas Distributing and must say that they are wonderful people to deal with. They are interested in having satisfied customers, and are willing to work with you in this situation. I will PM you the details.

I am very pleased when I find "no hassle" access to decision makers, and a customer service department that is dedicated to making sure the customer is satisfied with their purchase.

I believe that this attitude has been part of the success of Thomas Distributing during its 31 + years of business. If they have what you are looking for, go ahead and get it from them because they will take care of you in the long run.

I also contacted William of Maha to see if he has anything to add to our discussion.

Tom


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## coppertrail

SilverFox said:


> Hello Turbo DV8,
> 
> I contacted Thomas Distributing and must say that they are wonderful people to deal with. They are interested in having satisfied customers, and are willing to work with you in this situation. I will PM you the details.
> 
> I am very pleased when I find "no hassle" access to decision makers, and a customer service department that is dedicated to making sure the customer is satisfied with their purchase.
> 
> I believe that this attitude has been part of the success of Thomas Distributing during its 31 + years of business. If they have what you are looking for, go ahead and get it from them because they will take care of you in the long run.
> 
> Tom


+1


----------



## willchueh

Tom, got your email. I am happy to contribute. Having read the posts, following are the issues Turbe DV8 experienced - and my thoughts: 

1) Inconsistent discharge voltage between MH-C9000 and the BC-900

The MH-C9000 and BC-900 use different methods for measuring voltage during discharge. The MH-C9000 measures the voltage under a 1000mA load, while the BC-900 measures the open circuit voltage between the discharge pulses. We chose this particular design because the open circuit voltage does not fully reflect the condition of the battery and that the under-load voltage is the figure-of-merit for real devices. For instance, a highly resistive battery might show a high open circuit voltage (measured between discharge pulses). However, as soon as the discharge current is drawn, the voltage will drop significantly. Here is an example, for a battery with 0.1 ohm DC resistance, a open circuit voltage of 1.2V will give a under-load (1A) voltage of 1.1V. 

We've come across a lot of AAA batteries (well-known and off brand, new and old) that have DC resistances exceeding 0.3 ohm. Their open circuit voltage, measured between discharge pulses, actually never reach the cutoff and the discharge continues until the MOSFET is unable to draw current (due to insufficient differential voltage). The under-load voltage will already be 0.8V but the open circuit voltage will still be above the discharge cutoff. As a result, the discharge never ends! 

However, under-load voltage has one drawback - it also reflects the contact resistance between the charger and the battery. In a 2-point measurement (as used in the Mh-C9000 where only two points are used to measure the voltage across the battery, one on the positive terminal and one on the negative terminal), the voltage drop includes those across the contacts as well. Since no contact is perfect, it is possible to develop a small voltage drop between the battery and the charger. Commercial battery testers overcome this problem by using the so-called "4 point measurement" while two probes carry the current and two probes measure the voltage (so that the contact resistance is not measured). 

2) Non-monotonic discharge voltage (with respect to time)

It is normal to have a non-monotinic discharge voltage (and charge voltage as well) due a change in the battery resistance. This usually happens with batteries that have been sitting on the shelf for a while, and old batteries.

3) Pre-mature discharge termination 

It rarely happens, but it does. Did you encounter the problem frequently? on both units? Pre-mature discharge termination is most likely due to a sudden drop in the measured voltage (such that the charger sees a voltage less than 0.9V), often due to a jiggle to the battery, noise, etc. 

4) Why isn't the battery fully charged when DONE shows? Why the 2hour topoff charge?

It is a balancing act between undercharging and overcharging batteries. Maha design chargers differently depending on the target market. In the case of the MH-C9000, we favor undercharging in order to extend battery life. Typically, batteries are 93-95% charged when DONE pops up. This is when the user-set charging current stops and the 100mA top-off current kicks in. Our research showed that this termination strategy will substantially increase the life of the battery by preventing overheating. I think most folks here will agree that the MH-C9000 is a "cool" charger. 

5) Pre-mature charge termination

Charge termination issues do happen, but rarely. The MH-C9000 measures the battery voltage (both the absolute and relative value, and as a function of time), temperature (absolute and relative, and as a function of time) and puts the information into a matrix to evaluate whether to terminate the charge or not. At the design level, we decided that we prefer not to overcharge the battery. Occasionally, especially with new batteries or those sitting around for a while, premature charge termination would occur. However, missed termination is extremely rare because of our design choice. 

6) Capacity difference between the MH-C9000 and BC-900

BC-900, according to our measurement, tends to overestimate the capacity quite a bit (for instance, the Powerex 2700mAh capacity (1A charge/discharge) typically gets 2750mAh on the BC-900, when our laboratory-grade instrument consistently give about 2550mAh). This has to do with two things: 1) accuracy of the discharge current measurement, and 2) accuracy of the time base. The MH-C9000 has a 1% tolerance in the discharge current measurement. Furthermore, the MH-C9000 uses a quartz oscilattor time base (you can see them if you open the charger, I think there are some photos here on CPF) whereas the BC-900 uses a resistor-capacitor (RC) network as a time base which is less accurate. 

I trust the BREAK-IN capacity on the MH-C9000. It typically is within 2% of the capacity measured on a calibrated battery analyzer. 

I hope this answers some of the questions raised. 

William


----------



## Black Rose

Thanks for the information and explanations Will.

Greatly appreciated :thumbsup:


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## Turbo DV8

Thanks all, for the comments and efforts, and for contacting TD.



willchueh said:


> The MH-C9000 and BC-900 use different methods for measuring voltage during discharge. The MH-C9000 measures the voltage under a 1000mA load, while *the BC-900 measures the open circuit voltage between the discharge pulses*.


 


> I still think the problem you are seeing has to do with your cells.* I think those Eneloop AAA cells should show a mid point voltage of above 1.2 volts on the BC-900.*


 
Well, actually they did ... sort of. The BC-900 display was alternating between two values, and William's explanation above may help explain what I saw. For about 80% of the time, the midpoint voltages on the BC-900 were displayed as:

1.20-1.22-1.22-1.21-1.19-1.22-1.22-1.19

Then every five or ten seconds or so, the displayed voltage dipped, for a second, to the values I gave earlier:

1.19-1.19-1.18-1.19-1.18-1.18-1.19-1.18

Am I to assume from William's comment above that the higher voltages were the BC-900 indicating OCV, and the momentary lower voltages which flashed every five or ten seconds were an indication of the voltage under the applied load? This is sort of what I figured what was happening, that's why I just gave the lower midpoint voltages. But if I were to read the higher readings that were displayed the majority of the time, SilverFox, then the cells did indeed meet the 1.2v midpoint voltage on the BC-900 you cited. (with the exception of the last cell.)



> 5) Pre-mature charge termination: Charge termination issues do happen, but rarely.
> 
> 3) Pre-mature discharge termination: It rarely happens, but it does. Did you encounter the problem frequently? On both units?


 
I must be one unlucky guy, because I experienced both scenarios, on the same unit, right out of the gates! So far, each case has occurred once. At the end of the day, these occurrences will remain in the back of my mind.



> I still think the problem you are seeing has to do with your cells... If you have some other Eneloop AAA cells, they would be good to confirm what we are seeing.


 
Before I start another prolonged run of testing, please be specific about the process and readings I should be documenting.

Do you want me to two year old Eneloops, or the other eight new ones I received with the first eight? If the two year old ones, and possibly not all see a lot of use, should I just charge them, then discharge to get the midpoint voltages? Or first do a break-in, followed by a discharge for midpoint voltages? If I run them as-is, being in various states of condition, that may make it unlikely to be able to pin a potential problem either on a specific charger of the two, or the cells.

Any other specific requests for the testing before I begin? Thanks again for the help and contacting TD.


----------



## Turbo DV8

I forgot to ask...

I just finished a break-in on eight regularly-cycled Duracell 1700 cells, which must be more than three years old. New, the exceeded their rating, by a large margin even considering the test was on the optimistic BC-900. After break-in, the capacities were:

1767-1756-1699-1706-1752-1725-1661-1698

If I now wanted to run a couple cycles on them and observe midpoint voltages, what current is recommended to discharge the 1700 mAh cells? Is there a rule of thumb based upon cell capacity? Half the cell capacity rating, or half the actual capacity after break-in? If so, should I round up (900 mA) or down (800 mA) from the 1700?

Also, on the AAA Eneloops, I took the midpoint voltage at 400 mAh into the discharge. That just happens to be pretty close to half the tested capacity of the cells. However, for these Duracell 1700's, should I determine the midpoint voltage at half the tested capacity from the break-in?

Finally, what midpoint voltage for AA cells are we calling the dividing line between good and not-so-good?


----------



## Mr Happy

Turbo DV8 said:


> Before I start another prolonged run of testing, please be specific about the process and readings I should be documenting.
> 
> Do you want me to two year old Eneloops, or the other eight new ones I received with the first eight? If the two year old ones, and possibly not all see a lot of use, should I just charge them, then discharge to get the midpoint voltages? Or first do a break-in, followed by a discharge for midpoint voltages? If I run them as-is, being in various states of condition, that may make it unlikely to be able to pin a potential problem either on a specific charger of the two, or the cells.
> 
> Any other specific requests for the testing before I begin? Thanks again for the help and contacting TD.


Are the eight new Eneloops new and unused, or new but lightly used? It may not make much difference actually, but I'm just curious.

In this thread I have been testing four AAA size Duracell Pre-charged that I believe to be "Duraloops", i.e. Eneloops in different packaging. They were purchased new in 2008 and were unused until now.

I'll quickly recap the I process I followed in case you would like to follow along with four of your cells and compare with my posted numbers.

Out of the package, I discharged the cells at 200 mA.

Then a break-in cycle with 800 mAh entered capacity (at the end of which the cells were fully charged).

After the break-in, a discharge at 200 mA.

With the now empty cells, a charge/discharge cycle using 400 mA charge, 400 mA discharge settings. Three cycles were requested, so the cells underwent:

Charge (400 mA)/Discharge (400 mA)
Charge (400 mA)/Discharge (400 mA)
Charge (400 mA)/Discharge (400 mA)
Charge (400 mA)

Lastly, I discharged the now charged cells at 1000 mA and noted the voltages during the discharge and the final recorded capacities.

This process, of a discharge/break-in/discharge followed by a few 0.5 C charge/discharge cycles is probably a good way of enervating cells that may have been sitting around for a while.


----------



## Turbo DV8

Mr Happy said:


> Are the eight new Eneloops new and unused, or new but lightly used? It may not make much difference actually, but I'm just curious.


 
They are the latter eight of a total of sixteen I purchased from TD along with the MH-C9000's. I originally cycled them about three times between the Maha and BC-900 (not break-in) and that's it. 

I made a slight error before about the dates of manufacture of the eight AAA cells I was testing. I said all were April 2008. In fact, the first four are June 2008. All twelve other AAA Eneloops I got from TD are April 2008. 

My older AAA Eneloops are from April & October 2006.


----------



## Mr Happy

I've got some AA cells that I'm just topping up; two older Eneloops from 2006 and two Hybriloops that are more recent. I can run a 1 amp discharge on those and record the voltage profiles if you have any AA Eneloops to compare with.

I think I also have some Duracell 1700 cells that I got with my Power Gauge charger, but unfortunately I can't remember where I put them. If I find them I could run a discharge test on those too.


----------



## Mr Happy

Here is my discharge test of AA cells in case you want to compare:



Code:


1000 mA discharge test of AA Eneloops 1 & 2, "Hybriloops" 3 & 4
Cell     |  #1    #2    #3    #4
---------+---------------------------
 200 mAh | 1.14  1.22  1.21  1.22 V
 400 mAh | 1.11  1.19  1.19  1.20 V 
 600 mAh | 1.11  1.19  1.19  1.19 V
 800 mAh | 1.10  1.19  1.19  1.19 V
1000 mAh | 1.09  1.18  1.18  1.18 V
1200 mAh | 1.08  1.17  1.17  1.18 V
1400 mAh | 1.07  1.16  1.16  1.16 V
1600 mAh | 1.04  1.13  1.14  1.14 V
1800 mAh | 0.98  1.08  1.09  1.10 V
---------+---------------------------
Totals   | 1876  1895  1918  1930 mAh

It looks like the first Eneloop has gone high resistance. I don't know why that should be, it has been treated much the same as the second one. I guess it shows cells can go "bad" spontaneously and that you can't take even Eneloops for granted. I will have to run a break-in cycle on that cell and see if it recovers its original performance.


----------



## Chase2b

Don't mean to interrupt your posts but I have a (noob) question on the C9000.
I am doing a "break-in" cycle on 4 new AA's. The rating are 2000mAh.
I entered the required data on the C9000; capacity=2000.

The first cycle took 16 hours but the batteries are at 2900 mAh. I know that some overcharging will occur, but isn't 2900 TOO much? That's almost 50% more.

Note: I did do a full discharge on the batteries BEFORE the break-in cycle.

*** Please disregard this post. I just read in the beginning of this thread that it is normal for a 1.6 x overcharge. 1.6 x 2000 = 3200.
So the 2900 definately falls into that range.


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## coppertrail

This is normal during a break-in cycle, its not what the cells are actually holding.


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## Chase2b

Just read the first post of this thread. 1.6 x overcharge is normal.
1.6 x 2000 = 3200


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## Turbo DV8

Mr Happy said:


> I can run a 1 amp discharge on those and record the voltage profiles if you have any AA Eneloops to compare with... Here is my discharge test of AA cells in case you want to compare.


 
I would love to compare. Yet, before I begin another long test on AA Eneloops, I am awaiting instruction from SilverFox on how he thinks I should proceed on the AAA Eneloops, since he is trying to determine if I have cell issues and/or MH-C9000 issues.


----------



## SilverFox

Hello Turbo DV8,

The pressure is on...  

Let's go with your 2006 Eneloop cells.

Do 3 cycles of charge discharge on them and let's see what they do.

Are they also AAA cells?

Tom


----------



## Turbo DV8

SilverFox said:


> Hello Turbo DV8,
> 
> The pressure is on...
> 
> Let's go with your 2006 Eneloop cells.
> 
> Do 3 cycles of charge discharge on them and let's see what they do.
> 
> Are they also AAA cells?
> 
> Tom


 
Yes, AAA. I didn't hear many specifics, so I'll assume 300 mA charge and 400 mA discharge rates (as before) are adequate, and that this is a preliminary routine during which I do not need to record midpoint voltages and such. I have begun. Thanks.

Question about the "rests" in various modes. In the two hour rest after the first charge in refresh & analyze mode, is that 2 hours rest still giving the 100 mA "top-off" charge? Same question in Cycle mode. Is the 2 hour "rest" actually a 2 hour top-off at 100 mA? Or does the Maha only apply the top-off charge only after a straight charge.


----------



## TakeTheActive

William,

I acknowledge that you 'do this for a living' and thus understand it MUCH better than us, but I don't see how the following could be true: 


willchueh said:


> ...1) Inconsistent discharge voltage between MH-C9000 and the BC-900
> 
> *The MH-C9000 and BC-900 use different methods for measuring voltage during discharge. The MH-C9000 measures the voltage under a 1000mA load, while the BC-900 measures the open circuit voltage between the discharge pulses*. We chose this particular design because the open circuit voltage does not fully reflect the condition of the battery and that the under-load voltage is the figure-of-merit for real devices. For instance, a highly resistive battery might show a high open circuit voltage (measured between discharge pulses). However, as soon as the discharge current is drawn, the voltage will drop significantly. Here is an example, for a battery with 0.1 ohm DC resistance, a open circuit voltage of 1.2V will give a under-load (1A) voltage of 1.1V...


I own both a BC-900 and a MH-C9000. I recently moved the BC-900 upstairs to my HEATED den from my UNHEATED basement. Thus, I've been able to fairly continuously monitor the progress of both while I sit here "surfing the web". I don't see any WILD swings of voltage (as in going from UNDER LOAD to OPEN CIRCUIT) on the BC-900 while it's discharging. And, I do see it revert to charge when the discharge voltage hits 0.9VDC, just like the MH-C9000.

How can I prove to myself, here at home, that the BC-900 is measuring OPEN CIRCUIT while the MH-C9000 is measuring UNDER LOAD?

Thanks!


----------



## SilverFox

Hello Turbo DV8,

The first few charge/discharge cycles are designed to bring the cells back up to decent operating condition. No special care or observations are required during this part.

I seem to recall that the top off charge is applied in the cycle mode, but I don't know if it is applied during the refresh and analyze mode. There may be information on this in one of the C9000 threads, or you can run a test and see if the voltage climbs during the rest periods. If the voltage increases during the rest period, the cell is being topped off.

Tom


----------



## Black Rose

When I run the R&A on my cells, I always leave them in for the extra 2 hours, but I've never monitored the voltages.

I should toss a set of my Eneloops that have been sitting for 6+ months on an R&A cycle and see what happens.


----------



## willchueh

Turbo DV8 said:


> Question about the "rests" in various modes. In the two hour rest after the first charge in refresh & analyze mode, is that 2 hours rest still giving the 100 mA "top-off" charge? Same question in Cycle mode. Is the 2 hour "rest" actually a 2 hour top-off at 100 mA? Or does the Maha only apply the top-off charge only after a straight charge.



2-Hour top-off charge is applied in all modes except in DISCHARGE and BREAK-IN.

William


----------



## Turbo DV8

willchueh said:


> Typically, batteries are 93-95% charged when DONE pops up.
> William


 


willchueh said:


> 2-Hour top-off charge is applied in all modes except in DISCHARGE and BREAK-IN.
> 
> William


 
Interesting. So, if during break-in there is no top-off, and the cell is only charged to 93-95% of actual capacity when "DONE", then the capacity determined during a break-in is not an accurate capacity. But in this case, I do not understand your comment earlier:



> I trust the BREAK-IN capacity on the MH-C9000. It typically is within 2% of the capacity measured on a calibrated battery analyzer.


 
How can the break-in capacity be an accurate representation of a cells' capacity if it only charges to 93-95% due to not topping-off in break-in mode?

*EDIT: Never mind! Brain fart kept me from considering that break-in is terminated by time at 16 hours, not voltage. Therefore, no top-off needed. Duh...*


----------



## coppertrail

Let's take refresh/analyze mode for example. When charge is complete, let's say the cells are 93% full and show 1900 mAh for eneloop AA cells. 

Am I to assume that when the 2 hour top off charge is complete, I have 2+ Ah in my cells?


----------



## Turbo DV8

coppertrail said:


> Let's take refresh/analyze mode for example. When charge is complete, let's say the cells are 93% full and show 1900 mAh for eneloop AA cells.
> 
> Am I to assume that when the 2 hour top off charge is complete, I have 2+ Ah in my cells?


 
Not near my manual now, but if I recall, the R&A mode charges the cell, discharges, then charges again. Since William states that the R&A mode will apply the two hour top-off between the first charge and discharge, then the accrued discharge capacity should already take into account the energy added by the two hour top-off after the preliminary charge. That's the way I am reading it, anyway.


----------



## Mr Happy

Turbo DV8 said:


> Interesting. So, if during break-in there is no top-off, and the cell is only charged to 93-95% of actual capacity when "DONE", then the capacity determined during a break-in is not an accurate capacity. But in this case, I do not understand your comment earlier:
> 
> 
> 
> I trust the BREAK-IN capacity on the MH-C9000. It typically is within 2% of the capacity measured on a calibrated battery analyzer.
> 
> 
> 
> How can the break-in capacity be an accurate representation of a cells' capacity if it only charges to 93-95% due to not topping-off in break-in mode?
Click to expand...

It is because the break-in process charges the cell as close to 100% capacity as is possible. During the break-in charge, a current of 0.1C is applied for 16 hours. This applies a total charge of 160% of the cell's capacity, which saturates the cell with as much charge as it can reasonably be expected to hold. Essentially the break-in charge does not need a top-off because it is built into the charging process.


----------



## Mr Happy

coppertrail said:


> Let's take refresh/analyze mode for example. When charge is complete, let's say the cells are 93% full and show 1900 mAh for eneloop AA cells.
> 
> Am I to assume that when the 2 hour top off charge is complete, I have 2+ Ah in my cells?


When the cells are more than 95% full, the charge acceptance for further charge current is very low. That means that even if you feed 200 mAh into the cell, the whole 200 mAh is very unlikely to stick. Maybe only half of it will actually be stored.

This is why it is very difficult to charge batteries to 100% in a short time. Once the batteries are nearly full they convert a lot of the charge current to heat, which means you have to drop the charging current and take it slowly to avoid overheating the cells. The only possibility is to apply a small charge over a long period and be patient. This is what the C9000 does. There is no other way to go about it due to the way batteries behave.


----------



## Turbo DV8

Mr Happy said:


> During the break-in charge, a current of 0.1C is applied for 16 hours. This applies a total charge of 160% of the cell's capacity, which saturates the cell with as much charge as it can reasonably be expected to hold.


 
Yeah, that light bulb turned on for me just as you were composing your reply! I added a "brain fart" disclaimer to my post! Thanks.


----------



## Black Rose

Turbo DV8 said:


> Not near my manual now, but if I recall, the R&A mode charges the cell, discharges, then charges again. Since William states that the R&A mode will apply the two hour top-off between the first charge and discharge, then the accrued discharge capacity should already take into account the energy added by the two hour top-off after the preliminary charge. That's the way I am reading it, anyway.


Williams response didn't seem to directly answer the question you had about what happens in the rest periods.

I believe the top off charge is only applied after DONE is displayed, so it would not be applied at the 2 hour rest period following the first charge in R&A mode.

SURVEY SAYS: *WRONG*


----------



## Mr Happy

Black Rose said:


> Williams response didn't seem to directly answer the question you had about what happens in the rest periods.
> 
> I believe the top off charge is only applied after DONE is displayed, so it would not be applied at the 2 hour rest period following the first charge in R&A mode.


The top off charge _is_ applied during the two hour rest period after charging in Cycle mode, so I think it likely it is applied during R&A mode too, but I have not used R&A mode to find out for sure.


----------



## Black Rose

Mr Happy said:


> The top off charge _is_ applied during the two hour rest period after charging in Cycle mode, so I think it likely it is applied during R&A mode too, but I have not used R&A mode to find out for sure.


Guess I should have relied on the paper manual that came with my charger instead of the easier to access but outdated PDF version from the Maha site


----------



## mikevelarde

Mr. Happy:

When I chance upon the discharge capacity of a cell during the 120 min. rest before the final 16 hour 0.1C charge to the cell.

Can I safely assume that the discharge capacity is very near the available capacity after the 16 hour final charge of 0.1C ??

mikevelarde


----------



## Mr Happy

mikevelarde said:


> Mr. Happy:
> 
> When I chance upon the discharge capacity of a cell during the 120 min. rest before the final 16 hour 0.1C charge to the cell.
> 
> Can I safely assume that the discharge capacity is very near the available capacity after the 16 hour final charge of 0.1C ??
> 
> mikevelarde


Yes, you can. That same number is what the charger will report after the final charge completes. However, if the cell started out in very poor condition it may take more than one break-in cycle to bring the cell up to maximum capacity, in which case the available capacity may have increased even further after the second charge.


----------



## Turbo DV8

Here are the results of my 2006 AAA Eneloops for three cycles @ 300 mA charge and 400 mA drain:

Cycle #1: 772-775-770-762-770-761-767-771
Cycle #2: 782-777-771-771-778-764-777-781
Cycle #3: 782-777-772-772-778-765-776-781

I think they were in pretty good shape from the get-go. What's next, boss? Discharge at 400 mA and get midpoint voltages? Midpoint of 800 mA, or as close as possible to half the actual capacities above? The latter would be kind of buggy to do with eight cells so close in capacities, though. I already tried to be so perfect with the other cells and I went berserk as I was concentrating on one cell, another one zipped right past it's half way point right under the radar! :hairpull: The BC-900 is definitely nice in that respect of displaying the info for all four bays at simultaneously.


----------



## Mr Happy

Turbo DV8 said:


> Here are the results of my 2006 AAA Eneloops for three cycles @ 300 mA charge and 400 mA drain:
> 
> Cycle #1: 772-775-770-762-770-761-767-771
> Cycle #2: 782-777-771-771-778-764-777-781
> Cycle #3: 782-777-772-772-778-765-776-781
> 
> I think they were in pretty good shape from the get-go. What's next, boss? Discharge at 400 mA and get midpoint voltages? Midpoint of 800 mA, or as close as possible to half the actual capacities above? The latter would be kind of buggy to do with eight cells so close in capacities, though. I already tried to be so perfect with the other cells and I went berserk as I was concentrating on one cell, another one zipped right past it's half way point right under the radar! :hairpull: The BC-900 is definitely nice in that respect of displaying the info for all four bays at simultaneously.


Well, you have got lots of cells to work with. I discharged some Eneloop clones at 1000 mA back in post #253. You could discharge some of yours at the same rate and compare voltage profiles with mine, or we could wait and see what test SilverFox suggests you try.


----------



## Turbo DV8

Mr Happy said:


> I discharged some Eneloop clones at 1000 mA back in post #253. You could discharge some of yours at the same rate and compare voltage profiles with mine, or we could wait and see what test SilverFox suggests you try.


 
Since SilverFox has implicitly stated he would like to pinpoint whether the strange observations I observed earlier are cell related and/or charger related, I am waiting for further instruction from SilverFox. Pressure...

I can't say I am anxious to discharge my pampered AAA Eneloops at over 1C, though!


----------



## Mr Happy

On the Eneloop AAA data sheet there are discharge curves at 160 mA, 800 mA and 1600 mA. They show a mid-point voltage at 800 mA of about 1.24 V, and at 1600 mA of about 1.19 V. I have to say I have never managed to see voltages as high as that on the C9000. My 1000 mA discharge corresponds very closely to Sanyo's 1600 mA discharge curve.

However, their tests are conducted at a temperature of 25 C, and my room temperature is much more like 20 C, which would make a difference.


----------



## SilverFox

Hello Turbo DV8,

Let's try this...

Charge at 600 mA and after the 2 hour top off charge let the cells rest, in the charger, for about 30 minutes.

Now, discharge at 400 mA. Note the voltage at about 30 minutes into the discharge (in the range of 29 - 31 minutes should be fine).

Tom


----------



## Turbo DV8

SilverFox said:


> Hello Turbo DV8,
> 
> Let's try this...
> 
> Charge at 600 mA and after the 2 hour top off charge let the cells rest, in the charger, for about 30 minutes.
> 
> Now, discharge at 400 mA. Note the voltage at about 30 minutes into the discharge (in the range of 29 - 31 minutes should be fine).
> 
> Tom


 

Okay. I'll have to discharge again first, as they've already been charged at 300 mA and trickling overnight. The manual was not at all clear that the final cycle of "Cycle" mode adds a final charge. The manual just says, "Performs a charge-discharge cycle for a programmable number of times." I took this comment to mean that at the end of the third discharge cycle, the cells would be left drained, just as in "Discharge" mode. I'll try to get this done before I go to work this evening. If not, it may be a day or two before posting results, as I am having surgery Tuesday morning.


----------



## Mr Happy

Somewhere in the small print I think the manual does say that a final charge is performed at the end of Cycle mode. I was curious about this myself at the weekend and looked it up.


----------



## crofty

I can confirm the top off charge is applied in R&A also.

It would be nice to have a complimentary C9000 manual compiled by CPF members that gives these types of details. Maybe I`ll make a start if I get time and knowone beats me to it.


----------



## Black Rose

Turbo DV8 said:


> The manual was not at all clear that the final cycle of "Cycle" mode adds a final charge. The manual just says, "Performs a charge-discharge cycle for a programmable number of times." I took this comment to mean that at the end of the third discharge cycle, the cells would be left drained, just as in "Discharge" mode.


I've used the cycle mode numerous times to add charge/discharge cycles to my problematic cells to help wake them up.

At the end of the last "cycle", it does perform a final charge.




> I'll try to get this done before I go to work this evening. If not, it may be a day or two before posting results, as I am having surgery Tuesday morning.


Good luck :thumbsup: 

My wife had gall bladder surgery last Friday, so I'm home for part of this week taking care of her.


----------



## Turbo DV8

SilverFox said:


> Let's try this...
> Charge at 600 mA and after the 2 hour top off charge let the cells rest, in the charger, for about 30 minutes. Now, discharge at 400 mA. Note the voltage at about 30 minutes into the discharge (in the range of 29 - 31 minutes should be fine).


 
Results just in:

1.16-1.17-1.14-1.16-1.16-1.15-1.15-1.15

What's next? Do the same thing on the first set of eight 2008 cells that gave me grief earlier?


Doc called tonight and changed the slicing and dicing from AM to PM tomorrow. Great, an extra four hours I can fret with the sense of impending doom! If it weren't for the food and drink restriction after midnight tonight, I would practice _sensible _pre-op protocol...:drunk:


----------



## SilverFox

Hello Turbo DV8,

Those results are very respectable for cells that are a few years old.

Yes, run the other cells again. These are newer cells and I would hope that they would perform better than your 2006 cells.

It looks like the charger is working pretty well. Now let's see if the newer cells fall into place.

Tom


----------



## fireguy

My C9000 has a date code of 0H0Da.

I had a NiMH that I thought might have had a reversal. It was in a flashlight that got left on. I noticed that it was on and extremely dim. I put it in the C9000 and started a charge. One cell started to charge fine but the second had a voltage showing as 0.08. The capacity never went about 0 mAh. I removed it and put it in under Break-In and it did start to charge, jumping up to around 1 volt within a few seconds. I'll have to see how this cell behaves afterwards - maybe it was almost empty and the low-rate of charge for break-in was what it needed? I was trying to charge at 500 mA the first time. My guess is that this cell is likely toast.

The second thing I've noticed is that my C9000 never shows HIGH. I did have one old cell that it just wouldn't recognize. Out of curiousity, I popped in an alkaline to see what would happen and it started to charge. I removed it right away, though. I wonder if the newer C9000's have had their tolerances changed and sometimes an alkaline will pass through the checking? It was a brand new battery, so maybe a used alakaline would fail?


----------



## EngrPaul

I'm losing some digit segments on my charger.

Example:

1.238

Now appears as

1.23H


----------



## Turbo DV8

I'm looking at the manual, trying to find any hidden nuggets I may have missed, and it seems that with Cycle mode offered, the Refresh & Analyze mode is redundant. According to the manual, they both do the identcial routine, except the Cycle mode lets one program more than one cycle. But why clutter tha display with a Refresh & Analyze mode when one can simply use the Cycle mode and set the number of cycles for "1"?


----------



## pobox1475

Please delete...


----------



## TakeTheActive

EngrPaul said:


> I'm losing some digit segments on my charger...


What Date Code?

Where and when did you buy it?


----------



## SilverFox

Hello Turbo DV8,

If you have any cells that are not in everyday use, you can keep them "vibrant" by using the Refresh and Analyze function every 30 days. If they show signs of wearing down or come up a little bit short, then you can run then through the Cycle mode for 3 cycles.

Before you put them back into storate, run a discharge at 1 amp. Then they are ready to rest for another 30 days.

Of course if we are able to keep track of things this can all be done simply by using charge and discharge, so it seems that there is quite a lot of extra clutter involved... 

Tom


----------



## EngrPaul

TakeTheActive said:


> What Date Code?
> 
> Where and when did you buy it?


 
*0G0B01 from TD*

Edit: Here's a startup picture

UPDATE: Thomas Distributing had me ship the bad one back, they sent me a new one right away. THANKS!!!


----------



## jhellwig

fireguy said:


> My C9000 has a date code of 0H0Da.
> 
> I had a NiMH that I thought might have had a reversal. It was in a flashlight that got left on. I noticed that it was on and extremely dim. I put it in the C9000 and started a charge. One cell started to charge fine but the second had a voltage showing as 0.08. The capacity never went about 0 mAh. I removed it and put it in under Break-In and it did start to charge, jumping up to around 1 volt within a few seconds. I'll have to see how this cell behaves afterwards - maybe it was almost empty and the low-rate of charge for break-in was what it needed? I was trying to charge at 500 mA the first time. My guess is that this cell is likely toast.
> 
> The second thing I've noticed is that my C9000 never shows HIGH. I did have one old cell that it just wouldn't recognize. Out of curiousity, I popped in an alkaline to see what would happen and it started to charge. I removed it right away, though. I wonder if the newer C9000's have had their tolerances changed and sometimes an alkaline will pass through the checking? It was a brand new battery, so maybe a used alakaline would fail?




IT takes up to 2 minutes before they charger might kick the battery off on high impeadence. I tried it a couple of times and some times it just stopped charging and sometimes it said high.


----------



## Black Rose

EngrPaul said:


> *0G0B01 from TD*


 You've got a 3 year warranty on it, so you should be covered.


----------



## Turbo DV8

SilverFox said:


> If you have any cells that are not in everyday use, you can keep them "vibrant" by using the Refresh and Analyze function every 30 days. Before you put them back into storate, run a discharge at 1 amp. Then they are ready to rest for another 30 days.
> Tom


 
Why is it better to store a NiMH cell completely drained and refresh once a month, then drain again, rather than store charged, refresh once a month, and store chagred? Isn't draining them completely on a discharge and storing them thatbway going to cause them to be stored at that 0.9 volt critical level which can cause permanent damage? Not to mention, that means none of my shelf-queen cells will ever be ready to grab for fill-in use!

For those who have more than one MH-C9000, do the backlights on your units have equivalent brightness? One of mine has a noticeably dimmer backlight panel than then other. But not nearly as dim as the BC-900.

I think I observed another boner today on the MH-C9000 I ran a refresh and Analyze on two Hynrids which see daily use. I charged at 300 and discharged at 400. I was not able to monitor things, as then I left to be violated by the surgeon. When I returned, The test was done and "available capacity" was shown as 673 mAh and the time was shown as 63 minutes. The voltage stayed at 1.46 volts and the time remained at 63 minutes. Now, my head scratcher is this. As I read the manual, the 63 minutes shown is how long the last charge took. But how can a 800 mAh cell, if discharged fully during the discharge cycle, be charged fully in only 63 minutes at 300 mA? Something brain-farted in the Maha, once again, and unfortunately I was not present to hold it's hand.


----------



## digitor

Turbo DV8 said:


> But how can a 800 mAh cell, if discharged fully during the discharge cycle, be charged fully in only 63 minutes at 400 mA?



Probably the cell is slightly high impedance, so it terminated on voltage before it was fully charged. The top up charge would then add some more.

My original version 9000 doesn't suffer from these problems  , although I would think that it would miss terminating this cell at 400mA - I normally use 600mA on AAA's, and on a slightly crappy one, probably 800 (1C).

Also, it has other quirks which need to be taken into account (such as measuring voltage off-load)

Cheers


----------



## EngrPaul

Black Rose said:


> You've got a 3 year warranty on it, so you should be covered.


 
Thanks. A few days away from 1 year ownership. I'll give the warranty a try.


----------



## Mr Happy

Turbo DV8 said:


> I think I observed another boner today on the MH-C9000 I ran a refresh and Analyze on two Hynrids which see daily use. I charged at 300 and discharged at 400. I was not able to monitor things, as then I left to be violated by the surgeon. When I returned, The test was done and "available capacity" was shown as 673 mAh and the time was shown as 63 minutes. The voltage stayed at 1.46 volts and the time remained at 63 minutes. Now, my head scratcher is this. As I read the manual, the 63 minutes shown is how long the last charge took. But how can a 800 mAh cell, if discharged fully during the discharge cycle, be charged fully in only 63 minutes at 400 mA? Something brain-farted in the Maha, once again, and unfortunately I was not present to hold it's hand.


The next thing I would do is run a discharge on each cell at 200 mA and see what charge they hold. If you get a value of about 400 mAh it would indicate the last charge ended prematurely as you suspect, which which would mean the cell was not in best condition and needs some more TLC.


----------



## SilverFox

Hello Turbo DV8,

Cells age faster during self discharge than they do during normal use. Also, cells are unstable at full charge and they want to tend toward equilibrium.

When you discharge cells at 1 amp, they will end up with a voltage of around 1.2 volts. At the end of 30 days, they will still be at about 1.2 volts. If they drop to 0.9 volts, they are no longer "vibrant" and are headed toward the crap pile.

As you have pointed out, the downside to having vibrant cells is that they need to be charged prior to use. In my case, I usually am very good at planning ahead, and when I don't I use a 15 minute charger...  

I have 2 of the C9000 units and the light intensity is different between them.

Once again, keep in mind that when you charge outside of the recommended 0.5 - 1.0C range, it is better to expect that things won't go right and to be pleasantly surprised if they do.

Tom


----------



## Mr Happy

Regarding the aging question, this might be relative to how much aging you think is a problem for you. I have found with Eneloops that I can store them fully charged for months at a time and still find them within my capacity tolerance when I later come to use them. What usually happens in my experience is that after months of storage they develop a higher internal resistance and therefore run at a lower voltage on discharge. But after a bit of refreshing they come back to their original capacity and high discharge voltage. My 2006 vintage AA Eneloops are still testing at about 1900 mAh capacity, which is only 50 or 100 mAh down from what they might have achieved when new, and they have been stored in a charged state the whole time.


----------



## willchueh

Turbo DV8 said:


> When I returned, The test was done and "available capacity" was shown as 673 mAh and the time was shown as 63 minutes. The voltage stayed at 1.46 volts and the time remained at 63 minutes.



Dear Turbo DV8, 

The time displayed at the end of the refresh/analyze cycle (i.e. along with "available capacity") should be the *discharge* time. 

William


----------



## Burgess

Great thread here !

:twothumbs



So, tell me . . . .


I've been wondering about this . . . .


Suppose i have battery(s) now fully-charged on my Maha C-9000.

Then, suppose there is a power failure (120volt / mains) interruption.


Does the charger then begin slowly *Draining* the installed cells ?


Perhaps a silly question, but i've always wondered about it.



_


----------



## Turbo DV8

Burgess said:


> Suppose i have battery(s) now fully-charged on my BC-9000...


 

I smell a patent infringement somewhere in there!


----------



## Turbo DV8

> I think I observed another boner today on the MH-C9000 I ran a refresh and Analyze on two Hybrids which see daily use. I charged at 300 and discharged at 400. I was not able to monitor things, as then I left to be violated by the surgeon. When I returned, The test was done and "available capacity" was shown as 673 mAh and the time was shown as 63 minutes.


 


willchueh said:


> Dear Turbo DV8,
> 
> The time displayed at the end of the refresh/analyze cycle (i.e. along with "available capacity") should be the *discharge* time.
> 
> William


 
:thinking::thinking::thinking:How do we get 673 mAh out of cells drained at 400 mA in only 63 minutes?

Also, the manual states:

*Time:*
"This is the time elapsed for the particular routine such as charging, discharging or rest in the program."

I read this to mean that the last thing it does in Refresh & Analyze is charge, so therefore the time displayed is the time it took to charge.


----------



## Turbo DV8

> Originally Posted by *SilverFox*
> 
> 
> _Let's try this... _
> _Charge at 600 mA and after the 2 hour top off charge let the cells rest, in the charger, for about 30 minutes. Now, discharge at 400 mA. Note the voltage at about 30 minutes into the discharge (in the range of 29 - 31 minutes should be fine)._


 
Here are two sets of results for the voltage at 30 minutes @ 400 mA on the 2008 AAA Eneloops:

1) Eight new (broken in) 2008 Eneloops
2) Same eight new 2008 Eneloops, except switched chargers, ie. first four "A" cells went into charger "B" and vice versa.

1) 1.15-1.15-1.13-1.16-1.18-1.17-1.18-1.16
2) 1.15-1.16-1.15-1.16-1.17-1.16-1.17-1.17

Why did I run test #2 with the first four cells juxstaposed with the second four? Because I began to notice that no matter which cells go where, the first charger seems often to read slightly lower voltages. 

To help make clearer the two tests, imagine two chargers side-by-side. In test #1, the first four voltages are from the first four cells in charger "A" on the left. The second four voltages are from the second four cells in charger "B" on the right. For test #2, the two sets of four cells were reversed. That is, the first four cells in test #1 are the same cells as the last four cells in test #2. And the last four cells in test #1 are the same cells as the first four cells in test #2. Imagine a big "X" across the sets of four and you've got them matched up. So, as I arranged the table, charger "A" is always on the left, and charger "B" is always on the right. Notice even though the cells were reversed, the "A" charger voltages were consistently on the lower end, even if they had higher voltage figures when on charger "B". 

Am I obsessing? Am I trying to draw a conclusion where there is none? I think perhaps not, when I consider that all the questionably weird stuff that's happened all happened on charger "A"... cell prematurely terminating discharge due to prematurely dropping below 0.9v, and cell prematurely terminating charge, and such. 

Well, them's the results, anyway. I'm wondering if I shouldn't at least exchange the first charger, or not.


----------



## SilverFox

Hello Turbo DV8,

It looks like your cells have improved from your first set of data. I think this indicates that the original issue was with the cells and not the charger.

You do seem to be getting some strange occurances with that one charger. It's probably OK, but it would be nice if it was more consistent with the other one. If it were me, I would probably exchange it and take a chance that the replacement would be better matched to the one that I have left.

Tom


----------



## fireguy

I had a C9000 fright this evening. After running a set of cells through discharge, I removed them from the unit and it went ... dark. I checked the wall transformer, the connection, everything. A picture of my C9000 being shipped back for warranty work flashed through my mind. I put another cell into the unit and it came to life. I realized that since I took it out of the box several weeks ago, it's never been without at least one cell inside.  What a maroon! :nana:


----------



## Black Rose

:laughing:


----------



## SilverFox

Hello Fireguy,

 I got quite a chuckle out of that... 

Tom


----------



## Burgess

to Fireguy --


Welcome to CandlePowerForums !


:welcome:



Glad to hear yer' Maha C9000 "problem" was easily resolved.



_


----------



## jhellwig

I suppose I have a question about my c9000.


It seam like when I run the cycle mode my cells keep losing capacity until about the 4th cycle and then they even out. Does anyone else's do this? It isn't much maybe 10-30 mAh every time.


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## CliveBurt

I was wondering if someone knows if the discharge algorithm changed at some point in time on the C9000's?

I have two C9000's, one bought in early 2007 with a date code of 0G0B01 (we'll call that one "Charger A"), and the other bought in 2008 with a date code of 0G0KA (we'll call that one "Charger B"). If I take a battery and run any kind of test that tells me the capacity of the cell, be that a break in or refresh and analyse or discharge, charger B is anywhere from 93mAh to 130mAh lower than charger A. For instance, I just bought 8 new Eneloops and ran a refresh and analyse (C = 1000mAh, D = 500mAh) on each cell in both chargers and got the following results:

Cell/Charger A/Charger B/Difference
1/2008/1891/117
2/2017/1899/118
3/1952/1859/93
4/2005/1900/105
5/2030/1900/130
6/2045/1918/127
7/1978/1882/96
8/2020/1890/130

As far as I know both chargers use 0.9v as the termination voltage, so that only leaves the current measurement or the time measurement that isn't as accurate on charger B. I say charger B because charger A reads much closer to an Eneloops rated capacity and from my experience with Eneloops they are very consistent. I keep pretty good records of my batteries but never connected the dots, till now, that charger B reports lower capacities all the time. Is this a well known firmware change or is my charger B out of calibration?

Thank you in advance for any thoughts and help you can provide.

Clive


----------



## Mr Happy

I don't know, but to my mind charger B seems more likely to be true than charger A. I'm surprised though, that there could be such a difference between them.

What happens if you compare readings on the break-in cycle?


----------



## CliveBurt

Mr Happy,

Thank you for taking the time to reply. Is there any particular reason that you think charger B is correct?

As far as comparing Break-In cycles, that would be no, not yet. I have one under way right now that should provide the second part of a comparison but that won't finish the discharge till this time tomorrow. Is there a particular reason why you have asked about break-in cycles? If it is in order to know that the batteries were completely charged before the discharge was started then maybe the following will set your mind to rest.

I charged cells 1-4 on charger A for 6 hours at a charge rate of 1000mAh.
So that should have given them plenty of time for "Top off" charging and also start trickle charging. To my knowledge of the C9000 that should make these cells well charged. Then I discharged them at 500mAh. I then recharged them on charger A for 6 hours and discharged them on charger B at 500mAh. Here are the results:

Cell/Charger A/Charger B/Difference

1/1992/1885/107
2/2000/1887/113
3/1935/1846/89
4/2004/1886/118

I charged cells 5-8 on charger B for 6 hours at a charge rate of 1000mAh.
So that should have given them plenty of time for "Top off" charging and also start trickle charging. To my knowledge of the C9000 that should make these cells well charged. Then I discharged them at 500mAh. I then recharged them on charger B for 6 hours and discharged them on charger A at 500mAh. Here are the results:

Cell/Charger B/Charger A/Difference

5/1880/2007/127
6/1893/2021/128
7/1851/1954/103
8/1874/2001/127

These are the same cells as used in the Refresh and Analyse (RA) testing from my earlier post.

I have borrowed my brothers C9000 that was bought at the same time as my Charger B and has the same date code. I'm just charging up cells 1-4 so that I can run a discharge using my brothers charger. Should have those results later on today and also have break-ins running on chargers A & B that should be finished tomorrow. However, the cells being broken-in (BI) aren't the same cells that I've used so far, but I do have their history recorded.

Has anyone compared capacity results from Hobby chargers to C9000 for new Eneloops? I was wondering what sort of capacity to expect from a 2000mAh Eneloop.


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## Mr Happy

The reason I thought charger B was correct was a comparison with my own charger. I usually find that Eneloops measure in the 1850-1900 range when discharged after a normal charge on my C9000, compared to a measurement in the 1900-2000 range after a break-in. Therefore your charger B numbers seemed closer to what I am familiar with than charger A. Capacities much above 2000 mAh are quite unusual for Eneloops, and so measurements up to 2045 mAh seemed remarkable to me.

Note that I originally didn't have your additional information about waiting 6 hours for the top off to complete. In that case the sub-1900 capacities from charger B do seem suspect.

The reason I asked about break-in was this post from William Chueh higher in the thread:



willchueh said:


> I trust the BREAK-IN capacity on the MH-C9000. It typically is within 2% of the capacity measured on a calibrated battery analyzer.



If break-in capacities are expected to be within 2% of the truth, then a variation of more than 5% between chargers for the same cells would be significant and would seem to indicate that one or other charger is out of calibration.


----------



## CliveBurt

My first post was the results from refresh and analyse cycles which I thought included a 2 hour rest cycle during which I assumed that the top up charge was being applied (Might be wrong on that) before the discharge cycle starts, so I figured that it would be a quicker comparison than doing a BI.

I'll just show you the history of a set of cells that I have on BI right now so that you can add that into your thinking. These are Nexcell 1600mAh that came with a charger I bought 3 years ago. This isn't the full history just RA's and BI's:

Date/Operation/Charger/Cell #1/Cell #2/Cell #3/Cell#4
05-07-08/RA/A/1247/1146/1452/1197
06-07-08/BI/A/1240/1145/1481/1166
27-07-08/RA/A/1221/1124/1540/1161
30-12-08/BI/B/1122/1033/1456/1067
05-02-09/BI/A........

As you can see they're not really what one might call a matched set! They just happen to be one of the two sets that have had BI's run on charger B. In between the RA on 27/07/08 and the BI on 30/12/08 these batteries sat for 125 days and then were discharged and then charged. They then sat for 21 days and then discharged and charged. Then sat for 7 days and discharged and charged. I then installed them in a set of electronic bathroom scales until this morning when I discharged them in order to start a BI on charger A just to verify that they haven't really lost 100mAh of capacity since their last BI on charger A.

In about 3.5 hours I should have the discharge results from my eneloops on my brothers charger. If they're the same as charger B then I'm still not really any the wiser. I don't know if it's a firmware change or if charger A is out of calibration. It would be really nice if they match charger A, in which case my brother can take charger B back to the USA when he goes in a couple of weeks time. Anyone know how long it takes Thomas Dist. to sort out replacements for this kind of thing?


----------



## Turbo DV8

Mr Happy said:


> Note that I originally didn't have your additional information about waiting 6 hours for the top off to complete. In that case the sub-1900 capacities from charger B do seem suspect.


 


> My first post was the results from refresh and analyse cycles which I thought included a 2 hour rest cycle during which I assumed that the top up charge was being applied (Might be wrong on that) before the discharge cycle starts...


 
Of 30 AA Eneloop's I have, only 10% of them come in above 1900 mAh on a R&A at 500mA charge and discharge. Earlier, Maha posted here that the "_2-Hour top-off charge is applied in all modes except in DISCHARGE and BREAK-IN." 

_


----------



## digitor

FWIW, our local agent for the C9000 reckons that there is about a 6% difference in the capacities reported by the "old" and "new" versions of the charger. This seems to tally with the results obtained by CliveBurt.

Cheers


----------



## CliveBurt

Here are the results of cells 1-4 after being discharged on my brothers C9000 (Charger C) with the same date code as my Charger B:

Cell/Charger A/Charger B/Charger C

1/1992/1885/1885
2/2000/1887/1882
3/1935/1846/1839
4/2004/1886/1889

Thank you for your input Digitor, it confirms what I'm seeing.
I'm glad that my Battery history records have which particular charger the operation was carried out on. I have just recently retired a load of batteries not because of lost capacity but because of VERY rapid self discharge. A set of four Duracell 2650's 100% self discharge in 7 days!
I've gone through my histories and checked that this difference between chargers hasn't led me to the wrong conclusions. The only time it's led me astray was with some self discharge testing that I did to compare my Eneloops against some UniRoss Hybrios and Vapex instants. The UniRoss and Vapex were BI'd on charger A and then a long time later the discharge test was done on Charger B where as the Eneloops were discharged on Charger A so the Eneloops came off looking much better. It's just a pain in the rear having to now possibly wait to get a set of batteries on the "right" charger. That's why I bought a second C9000! So I didn't have to wait for a BI to finish.

I wonder if Thomas Dist. will exchange my old charger? Sod's Law says I'll end up with a new charger that will be different in it's firmware and I'll end up back where I started. Still, the AAA contacts couldn't be any worse than the ones on my Charger A.


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## Mr Happy

The only puzzle is my charger is also from 2007 (0G0E01 from memory), but it produces results similar to chargers B and C.


----------



## bmoorhouse

I have a two year old C9000 (code 0G0B01). It seems to work okay with AA batteries with only the occassional missed termination. With AAA batteries, however, it is 50-50. Last night I forgot to check it before going to bed and found it had forced 3150 into an 800 mah battery. Unfortunately, that isn't the fist time.

I bought this charger in particular because I liked the way the delta-V was suppose to work to ensure my batteries were fully charged (maybe slightly overcharged) every time. I knew I could charge the batteries for my flash and know I was getting max performance when the C9000 said Done.

After cooking another set of batteries last night, I returned to this board after being away for about a year and found that there is apparently a third firmware version that terminates charging at 1.47 volts instead of the delta-v.

I am considering replacing my current (firmware version 2) model with the new one to better protect my AAAs, but am concerned that doing so will negate the reason I bought the thing in the first place in that Done will no longer mean Done, but only Nearly Done.

In general, are people with the third version happier with it, or should I stick with my current one and just accept that my AAAs are going to get toasted every once in a while? Are there any other changes between the 2nd and 3rd versions I should know before I decide (besides the brighter screen)?


----------



## Mr Happy

I have an 0G0D01 model and it does have the 1.47 V feature. Until now, I had thought all 0G0 models had that.

Could you give more information like make and age of the battery in question, and charging rate used?


----------



## fireguy

bmoorhouse said:


> Last night I forgot to check it before going to bed and found it had forced 3150 into an 800 mah battery. Unfortunately, that isn't the fist time.


I have a C9000, dated 0H0DA. Last night was the first time it ever missed termination on a AAA. I was charging an old Energizer 800 mAh AAA at 500 mAh. I noticed this when there was 2700 mAh put into the cell. The voltage displayed on the C9000 at this point was 1.35 volts. This is a very old cell. It had been charged the week before and the voltage (measured with a DMM) was 0.89V. I suspect this cell is gone and wonder if any charger would have terminated? I'm going to try it in another smart charger I have to see what happens. I wonder if the cell you were charging has problems? This is the only AAA that I have ever had any problems with in the C9000.


----------



## bmoorhouse

Most of my AAAs are Rayovak Hybrids, are about a year old, and have been used in my toddler's toys. I typically charge them at 400 ma as they are rated at 800 mah. If I use a decharge mode, I discharge them at 200 ma. When I pulled the battery this morning, I believe the voltage was at 1.51.

My concern is that it is not always the same battery that fails to terminate, nor is it the same slot. It is completely random.

I have two different batteries in the charger for an RA cycle. I started them within a minute of each other. The display is now showing:

Slot 2: Charging 1444 mah 390 ma 244 min 1.41 v
Slot 3: Resting 905 mah 92 min 1.43 v

It looks to me like the cell in slot 2 failed to terminate and has been charging the whole time that the cell in slot 3 has been resting. I did not note the time, so I do not know if the battery that missed last night failed to terminate on the initial charge or on the final charge.


----------



## digitor

Mr Happy said:


> The only puzzle is my charger is also from 2007 (0G0E01 from memory), but it produces results similar to chargers B and C.



I think the "G" indicates updated firmware - my C9000 is 0FAB02, and is the initial firmware version. I seem to remember there was a couple of revisions, with the "repeating digit" bug the last thing to get fixed.

Cheers


----------



## Mr Happy

bmoorhouse said:


> Slot 2: Charging 1444 mah 390 ma 244 min 1.41 v
> Slot 3: Resting 905 mah 92 min 1.43 v
> 
> It looks to me like the cell in slot 2 failed to terminate and has been charging the whole time that the cell in slot 3 has been resting. I did not note the time, so I do not know if the battery that missed last night failed to terminate on the initial charge or on the final charge.


It does indeed look like slot 2 has failed to terminate. Does the cell feel hot at this point? One would expect it to be getting quite warm with that charge current for so long.


----------



## Mr Happy

digitor said:


> I think the "G" indicates updated firmware - my C9000 is 0FAB02, and is the initial firmware version. I seem to remember there was a couple of revisions, with the "repeating digit" bug the last thing to get fixed.


I think I read somewhere that the first two letters are the year and the second two are the month.

So 0F = 2006, 0G = 2007, 0H = 2008; 0A = Jan, 0B = Feb, etc.

My charger is actually 0G0D01, which would make it April 2007. I don't know exactly which month and year the second firmware revision was introduced. I do know that my charger has a digit display bug in Cycle mode that was apparently fixed in the third revision.


----------



## bmoorhouse

Yes, the cell did feel warm, though not as warm as the one I pulled out this morning with over 3000 mah.

I went ahead and pulled the cell out. I figured no sense in waiting for the 4000 mah cut-off. 

One thing that surprised me though is that it was only showing 1.41 volts. Do the volts start going down at some point? Otherwise the 1.47 v cutoff on the new model wouldn't have helped here. And again, I could be wrong, but I am fairly positive the one I pulled this morning was at 1.51 v.


----------



## Mr Happy

bmoorhouse said:


> Yes, the cell did feel warm, though not as warm as the one I pulled out this morning with over 3000 mah.
> 
> I went ahead and pulled the cell out. I figured no sense in waiting for the 4000 mah cut-off.
> 
> One thing that surprised me though is that it was only showing 1.41 volts. Do the volts start going down at some point? Otherwise the 1.47 v cutoff on the new model wouldn't have helped here. And again, I could be wrong, but I am fairly positive the one I pulled this morning was at 1.51 v.


Yes, pulling the cell was wise.

Those voltages do seem low to me. This is pure speculation, but one way a cell could have a low voltage, high charging current, and yet not be sizzling from overcharging is some kind of internal short circuit fault in the cell. It is all a mystery to me though, I don't quite know what is going on there. I don't own any Hybrids -- I always use eneloops -- and eneloops go up above 1.50 volts every time on a break-in cycle which means the 1.47 V cut-off always catches them on a normal charge.

I remember some questions in a thread somewhere about how to insert AAA cells in the charger. Can I check that you are pushing the cells right down firmly into the bottom of the slot so they make good contact with the temperature sensor? That's because even if charging doesn't terminate on voltage, it should eventually terminate on temperature.


----------



## Bones

bmoorhouse said:


> ...
> I am considering replacing my current (firmware version 2) model with the new one to better protect my AAAs, but am concerned that doing so will negate the reason I bought the thing in the first place in that Done will no longer mean Done, but only Nearly Done.
> 
> In general, are people with the third version happier with it, or should I stick with my current one and just accept that my AAAs are going to get toasted every once in a while? Are there any other changes between the 2nd and 3rd versions I should know before I decide (besides the brighter screen)?





bmoorhouse said:


> ....
> 
> I went ahead and pulled the cell out. I figured no sense in waiting for the 4000 mah cut-off.
> 
> One thing that surprised me though is that it was only showing 1.41 volts. Do the volts start going down at some point? Otherwise the 1.47 v cutoff on the new model wouldn't have helped here. And again, I could be wrong, but I am fairly positive the one I pulled this morning was at 1.51 v.



It's my understanding that if your charger is reaching 1.51 volts it must be the first release of the MH-C9000.

The second release revised the charging protocols, and I'm not aware of any credible indication they have since been altered.

I specifically mention this because if my understanding is correct, then the capacity cutoff of your charger is 20000mAh and not 4000mAh.

I know of at least two further improvements since the firmware revision to the charging protocols. The first resolved the repeating digits bug in the cycle settings, the second increased the brightness of the display.

As well, at some point a nub was added to the negative tang for the AAA cell similiar to one on the negative tang for the AA cell.

It's also my understanding that the revision to the charging protocols was made on the fly in early 2007, and if your charger was built during this period, the only way to be certain it has the revised firmware is by determining its behaviour.

Probably the easiest way would be to point a camcorder at it while it's charging better quality cells that take it past the 1.47 volt termination point of the revised version, and then see what it does.


----------



## Black Rose

Mr Happy said:


> I think I read somewhere that the first two letters are the year and the second two are the month.
> 
> So 0F = 2006, 0G = 2007, 0H = 2008; 0A = Jan, 0B = Feb, etc.
> 
> My charger is actually 0G0D01, which would make it April 2007. I don't know exactly which month and year the second firmware revision was introduced. I do know that my charger has a digit display bug in Cycle mode that was apparently fixed in the third revision.


I have a 0G0KA that was purchased in March 2008. 
It has the cycle mode digit display bug fix.


----------



## Bones

bmoorhouse said:


> ...
> 
> I am considering replacing my current (firmware version 2) model with the new one to better protect my AAAs, but am concerned that doing so will negate the reason I bought the thing in the first place in that Done will no longer mean Done, but only Nearly Done.
> 
> ...



Perhaps you will find nearly done a more reasonable comprimise when placed in the context of this statement by William Cheu, the lead engineer on the MH-C9000:



willchueh said:


> ...
> 
> 4) Why isn't the battery fully charged when DONE shows? Why the 2hour topoff charge?
> 
> It is a balancing act between undercharging and overcharging batteries. Maha design chargers differently depending on the target market. In the case of the MH-C9000, we favor undercharging in order to extend battery life. Typically, batteries are 93-95% charged when DONE pops up. This is when the user-set charging current stops and the 100mA top-off current kicks in. Our research showed that this termination strategy will substantially increase the life of the battery by preventing overheating. I think most folks here will agree that the MH-C9000 is a "cool" charger.
> 
> ...



As well, SilverFox has determined that the revised MH-C9000 actually provides a more complete charge than the BC-900, which terminates on Negative DeltaV the same as your original edition MH-C9000:

http://www.candlepowerforums.com ... post2650477

I'm presuming that the two hours top-off charge was included with the MH-C9000, but it's not stated.


----------



## Turbo DV8

Is it my imagination, or is the contact area of the thermal sensor with AAA cells kinda skimpy? Only a very small sliver of the very bottom of AAA cells actually contacts the sensor, and only half the width of the sensor is in contact with AAA cells. Seems kinda iffy to me. I wonder how effective the safety thermal termination functions on AAA cells with this charger...

Also, the negative contacts for the AAA cell just barely nips the end of the cell, which has caused me some charging problems no matter how hard I try to make sure the cell is pushed all the way down. 


The two figures I need most from the display are mAh and voltage. I hate having to wait for each cell to cycle mAh-current-time to eventually show the voltage in the last display.

My wish list for the reordering of the display sequence:

mAh
Voltage
Current
Time

I actually find more need of time than current, but I place current before time to separate mAh from mA in the cycle, to better avoid inadvertently mistaking mA for mAh.


----------



## EngrPaul

UPDATE: Thomas Distributing had me ship the bad one back, they sent me a new one right away. THANKS!!!


----------



## N162E

bmoorhouse said:


> Most of my AAAs are Rayovak Hybrids, are about a year old, and have been used in my toddler's toys. I typically charge them at 400 ma as they are rated at 800 mah. If I use a decharge mode, I discharge them at 200 ma. When I pulled the battery this morning, I believe the voltage was at 1.51.
> 
> My concern is that it is not always the same battery that fails to terminate, nor is it the same slot. It is completely random.


Have you considered a LaCrosse BC-700 or 900? This could be a good fit for you. The LaCrosse chargers sense DV at low ma much better. I have both. As I prefer slower charging I charge on the Lacrosse and do my discharges on the Maha.

My C-9000s are very early version and simply will not terminate below a 700 ma rate. On my Lacross's I can charge AAA at 200ma and AA at 500ma and have reliable termination and full cells at the end of charging.

As always quality and condition are important in charging and useage. Once a cell has had a "Good Cooking" it will probably never be the same and may be erratic/useless from that time on-time for the recycle bin.


----------



## Timdog68

Hi,
I have a new C9000,date code 0G0KA from Thomas.
I also bought a couple 4 packs of Eneloops from them as well.
I charged them and they are all were around 1850-1900 mah.
I am doing a break-in on 4 of them and noticing the voltage is up to 1.50V on all of them and its still charging.
Is it normal to get above the 1.47 volt cutoff when in Break-in mode?
Thanks,
Tim


----------



## SilverFox

Hello Tim,

Yes.

Tom


----------



## NiOOH

Yes, in break-in mode the cells are charged at 0.1C for 16 hours timed, i.e. the termination doesn't work. Fot the last few hours it is normal for the cells to reach voltages around 1.50 V. In any other mode the primary charge termination is done on maximum voltage set at 1.47 V. If a voltage drop is detected below this voltage (happens with lower quality cells) the charge is also terminated. It is also normal to see voltages higher than 1.47 during top-off (2 hours after "done" appears on the display) especially with AAA cells.


----------



## jblackwood

SilverFox said:


> Hello Tim,
> 
> Yes.
> 
> Tom



I love this response! Nuff said.


----------



## NeoteriX

Hi, I just picked up one of these (semi) locally at a Battery Plus store. I was a little disappointed that the included manual was so meager, but now when I checked the CPF forums, I'm a little blown away by all the information present 

A few Qs: 

- My production code is 0H0FA -- the ones I usually see people mention have 0F0 or 0G0 in the nomenclature. What should I know about or can expect from the 0H0 series? Is this the newest incarnation? Are there problems with it?

- I've got a handful of batteries in a bag collecting dust (some of them date over 8 years old ) that I was hoping to revitalize with this charger for non-demanding use (for TV remotes and the like). Which process is the best way to do this? R/A or Break in?

- On that same note, how do I know when to give up on the battery and chuck 'em out (recycle)? Is there a certain % of its original life that they are effectively no good?

- Is it safe to go to sleep while the batteries are charging? I had read a few posts (that I don't quite understand fully) where the batteries did not stop charging past their design limit b/c something something terminating voltage. I was worried that I would have hard metal batteries melting and exploding while I slept, but at the same time, these cycles can get quite long!

- When the information online says to charge at .5C and discharge at .25C, is this of the "rated" capacity on the side of the battery, or the "effective" capacity as determined by Refresh/Analyze? The first set of cells I have were rated at 2400 mAH but R/A concludes they have a discharge capacity of ~1400-1500 mAH. 

- How closely do people adhere to the .5C/.25C rules? It's nice that my batteries stay pretty cool and comfortable during the process, but I can get a little impatient (see fear about burning in sleep, _supra_); I am coming from a Duracell 15-minute charger. :sigh: Yes, it's complete garbage, and I probably fried some of my batteries over the past year, but 15 minutes is pretty enviable. 

Thanks in advance!


----------



## Mr Happy

NeoteriX said:


> Hi, I just picked up one of these (semi) locally at a Battery Plus store.


Congratulations on your purchase. You have obtained a wonderfully entertaining toy, er, I mean a powerful and sophisticated piece of test equipment... 

The first two letters of the production code seem to be the year of manufacture, and I think 0H is 2008. You cannot directly tell much more than that.

The main thing to do is get familiar with how your cells and the charger behave.

If you have really old and unknown batteries, the best thing to start with is a Break-In cycle. This is long and slow, but safe and cool, and will give you a baseline idea of the battery capacity. When entering the capacity for the Break-In, use the capacity given on the label.

If you have new and regularly used batteries, you can treat them differently. If they are AA cells, discharge them to empty at 500 mA and then put them on a charge at a rate from 0.5C to 0.8C (use the label capacity for C). Watch this process and monitor how warm they get (if they get uncomfortably hot you might stop the charge prematurely). What you are looking for is to see how the charge terminates. Does the voltage reach 1.47 V and then say DONE soon after, or does the voltage fail to reach 1.47 V and let the cells continue charging for a bit longer before saying DONE? Newer and better batteries will tend to hit 1.47 V whereas older batteries will not reach it. Before you leave the charger unattended you want confidence in how effectively the charge process will terminate. The ideal is for the supplied charge to be no more than 110-120% of the label capacity.

After DONE appears, leave them on the charger for another two hours and then discharge them at 500 mA. See how this capacity compares to the label. Also watch the voltage during the discharge. For good batteries the voltage will start out above 1.30 V and will hit 1.20 V about half way through the discharge. For bad batteries the voltage will be noticeably lower. Check the capacity reported at the end. Good batteries will be within 90% of the label, bad batteries significantly lower.

If you have bad batteries, my experience is just go straight to a Break-In cycle. This is the "big gun". I have not found it worth messing around with Refresh/Analyze cycles for improving battery health.


----------



## NeoteriX

Mr Happy said:


> Does the voltage reach 1.47 V and then say DONE soon after, or does the voltage fail to reach 1.47 V and let the cells continue charging for a bit longer before saying DONE? Newer and better batteries will tend to hit 1.47 V whereas older batteries will not reach it. Before you leave the charger unattended you want confidence in how effectively the charge process will terminate. The ideal is for the supplied charge to be no more than 110-120% of the label capacity.



Thanks for the information! It's really helpful! 

So for all niMH batteries, the 1.47V figure is key? How long do I have to watch to determine that it is not hitting 1.47 and still going on?


----------



## NiOOH

NeoteriX said:


> Thanks for the information! It's really helpful!
> 
> So for all niMH batteries, the 1.47V figure is key? How long do I have to watch to determine that it is not hitting 1.47 and still going on?


 
As a rough guide, charging at 0.5-1 C, the 1.47 V point is reached when the input capacity is roughly equal to 90% of the capacity of the cells. Thus, for Eneloops you should be watching them when the input capacity reaches 1800 mA, or 2 hours after the begining of the charge at 1 Amp. If some of the cells cannot reach 1.47 V they will get considerably warmer than the others. You may be even able to see the voltage dropping by 0.01 V a short while before the charger terminates.
This however is unlkely to happen with good quality cells. I've used the c9000 with 16 eneloops 8 Hybryos, 4 2500 mAh Sanyos and 8 1700 mAh Sanyos and all of them terminate without problems at 1.47 V. The only cells that may have problems are two (out ot four) Varta Ready 2 Use cells that reach 1.46 V


----------



## Turbo DV8

The C-9000 just missed a termination on a AAA ROV Hybrid @ 300 mA charge rate. I got home and it had put 2200 mAh through it. It wasn't particularly hot, but should I just toss it anyway?


----------



## SilverFox

Hello Turbo DV8,

Do a discharge at 400 mA, then do a charge at 600 mA and see what happens.

If your discharge capacity is less than 80% of the original capacity, you can stop with that and recycle the cell. On the other hand, if it has decent capacity, it may just need some exercise to get back into shape.

Tom


----------



## Turbo DV8

SilverFox said:


> Hello Turbo DV8,
> 
> Do a discharge at 400 mA, then do a charge at 600 mA and see what happens. If your discharge capacity is less than 80% of the original capacity, you can stop with that and recycle the cell.


 
I did a discharge on it @ 400 mA this morning, and got back 668 mAh, which is on par with the lowest performing Hybrids I have, one of which is known to have high self-discharge. But at this point, I have no confidence in the 668 mAh figure, as well as waning confidence in the charger in general, due to the following.

When the Hybrid missed it's termination last night, I took it off the charger for an hour. My plan was to drain it and do a R&A. Before I went to bed, I set it to discharge at 100 mA, so it would be ready for R&A this morning. When I got up, the charger said DONE, but it indicated it had been in charge mode, not discharge, and it displayed "839 mAh." I know I did not accidentally set it to charge mode instead of discharge, as there is no 100 mA charge rate! This is the second time I have come back to the charger to find it finished in a mode other than what I set it for. Has this happened to anyone else?

So at this point, the 668 mAh figure and 839 mAh figure are worhtless to me. Did it charge, discharge, who knows? I am finding this charger to be just too finicky in several respects. I know some people don't trust the La Crosse, but I tell you, so far this Maha has given me more grief and strange occurences than my three La Crosse's ever have (since adding the filter caps, of course!) So I shall charge at 600 mA and do another 400 mA drain, and see what happens... if the C-9000 will let me. As far as the discharge capacity being less than 80% of the original capacity, unfortunately, I have no prior capacity data from this cell drained on the Maha, only the BC-900, so I won't be able to really compare before and after capacities.


----------



## Power Me Up

Turbo DV8 said:


> Before I went to bed, I set it to discharge at 100 mA, so it would be ready for R&A this morning. When I got up, the charger said DONE, but it indicated it had been in charge mode, not discharge, and it displayed "839 mAh." I know I did not accidentally set it to charge mode instead of discharge, as there is no 100 mA charge rate! This is the second time I have come back to the charger to find it finished in a mode other than what I set it for. Has this happened to anyone else?



It sounds like you might have had a very short power outage - long enough for the C9000 to reset. When the C9000 resets, it defaults to charging at 1000 mA after a few seconds, so I'd say that it had finished the discharge before the reset and then fully charged the cell - hence the 839 mAh being displayed...


----------



## Turbo DV8

Power Me Up said:


> It sounds like you might have had a very short power outage - long enough for the C9000 to reset. When the C9000 resets, it defaults to charging at 1000 mA after a few seconds, so I'd say that it had finished the discharge before the reset and then fully charged the cell - hence the 839 mAh being displayed...


 
Good to know. If it happens again, I should note charge current and time also. However, I was concurrently running break-ins on the second C-9000 at the same time, and there was no disruption on that unit. They were still in break-in mode.


----------



## TakeTheActive

NeoteriX said:


> ...So *for all niMH batteries, the 1.47V figure is key?* How long do I have to watch to determine that it is not hitting 1.47 and still going on?


For *ALL* recent versions of the Maha MH-C9000 (SEARCH the CPF Archives for the *exact* version of the update), for *ALL* supported cell chemistries (NiCD and NiMH), MaxV has been reduced to 1.47VDC.

This does not apply to any other manufacturer's chargers.


----------



## Bones

Turbo DV8 said:


> Good to know. If it happens again, I should note charge current and time also. However, I was concurrently running break-ins on the second C-9000 at the same time, and there was no disruption on that unit. They were still in break-in mode.



It's curious that only one would have re-set. Perhaps a more sensitive power supply?

As well, have you been encountering problems with both your units, or have the problems you've been periodically reporting all been with the same unit?


----------



## Turbo DV8

Bones said:


> It's curious that only one would have re-set. Perhaps a more sensitive power supply?
> 
> As well, have you been encountering problems with both your units, or have the problems you've been periodically reporting all been with the same unit?


 
One more than the other, but not exclusively to one. I don't think I had a brief power outage. I have a printer that needs resetting if power is disrupted even for a fraction of a second, and it didn't fault code on me.


----------



## Mr Happy

The Hybrid doesn't have insulation that wraps over the negative end, does it? I had exactly the same problem of certain AAA cells resetting themselves and it was due to poor electrical contact with the charger. In the end I cut the insulation back to leave the negative pole fully exposed. I don't know if this is what happened with you, but it is a possible cause.


----------



## Turbo DV8

Mr Happy said:


> The Hybrid doesn't have insulation that wraps over the negative end, does it? I had exactly the same problem of certain AAA cells resetting themselves and it was due to poor electrical contact with the charger.


 
No, the ROV Hybrid has no wrapping that extends into the negative terminal. And again today I had yet another episode. I set a Hybrid in a slot and made every reasonable effort to ensure the negative end was as far down as possible. I set it for discharge, and it appeared to take, but less than a minute later when I looked at the charger, the charger no longer recognized a cell in that slot, as if I had never placed anything there at all. No shrink wrap, and I practiced far more effort than should ever be necesary to ensure good contact, and the chargers negative AAA contacts still only barely nip the gnat's-*** edge of the cells. As far as I am concerned, the negative contacts on the C-9000 are defective by design. How it could get to market, and remain unchanged in this respect, is beyond me. I'm almost ready to ask TD if they will take returns after two months, if only to save you from having to read my whining here. It seems nearly every other time I use the charger, it makes me :hairpull: Man, if _only_ the La Crosse could do a simple discharge without recharging afterward, and I would leave the C-9000 in the dust.


----------



## SilverFox

Hello Turbo DV8,

I fully support you in your complaint about the negative contact used for AAA charging...

I have numerous times heard a "plink" as an AAA cell popped loose during charging or discharging. I actually modified my chargers to take care of this, but Maha should have incorporated this modification into their design, so the end user doesn't have to do it.

The modification was simple. The unit is opened up and the AAA negative terminal is simply bent a little to remove some of the original bend. This raises the second bend to above the edge of the AAA cell, and gives a much more reliable contact.

I totally agree with you that this "non feature" should be addressed by Maha.

Tom


----------



## rickd

I have a dozen ROV AAA Hybrids, but I don't recall having difficulty seating them. I have had problems seating batteries in slot 3 on my older 0F model, but no issues with the newer 0H.

Personally, I would just get ride of the AAA ROV Hybrids. I recently tested mine using the break-in mode and all where below 600mah. Some were as low as 350mah. Doing some cycling on them is slowly bringing them back up, but none are above 700mah yet. I can't use the RA on the C-9000 with these as they will miss the termination point, recharging at 600ma. They also missed their termination point on my 801D, which is unheard off. This is not a charger problem, just the crappy batteries.

I also have a dozen AAA Eneloops; these all come in around 800mah (or higher). My Eneloops are dated 2006/06 and have the roughly same amount of discharges as the ROV.


----------



## Black Rose

I've never had an issue with AAA cells popping out of their slots on the C9000. This applies to ROV Hybrids, Eneloop, Titanium Enduro, or non-LSD ROV AA batteries.

When I put a AAA cell in, I put the negative end in first and the push the positive end in.

I then roll each cell side to side to make sure it is deeply seated.
In almost a year of use, not one AAA has ever escaped it's slot in the C9000.

When I use my C9000, I use the lift rod in the back so the charger is at an angle. Maybe that has something to do with it.


----------



## Black Rose

SilverFox said:


> The modification was simple. The unit is opened up and the AAA negative terminal is simply bent a little to remove some of the original bend. This raises the second bend to above the edge of the AAA cell, and gives a much more reliable contact.


If you get the chance, could you post a picture of that?

Even though I haven't had this problem yet, I'd like to see what you did should mine start to act up as it gets more use.


----------



## Bones

Black Rose said:


> If you get the chance, could you post a picture of that?
> 
> Even though I haven't had this problem yet, I'd like to see what you did should mine start to act up as it gets more use.



I believe the modification SilverFox is referring to would consist of twisting the lateral portion of AAA tang in the image on the left in a counter-clockwise direction to bring it closer to horizontal:



Bones said:


> I thought it might be helpful to be able to visualize the shape of the contact tangs when deciding how to load the MH-C9000:
> 
> 
> 
> 
> 
> 
> ...



Incidentally, on more recent versions of the MH-C9000, the little protrusion you see on the AA cell contact point has been duplicated on the contact point for the AAA cell.

This makes it easier to rotate AAA cells along their horizontal axis to maximize contact and somewhat reduces the risk of a torn wrapper.


----------



## Bones

SilverFox said:


> Hello Turbo DV8,
> 
> I fully support you in your complaint about the negative contact used for AAA charging...I fully support you in your complaint about the negative contact used for AAA charging...
> 
> I have numerous times heard a "plink" as an AAA cell popped loose during charging or discharging. I actually modified my chargers to take care of this, but Maha should have incorporated this modification into their design, so the end user doesn't have to do it.
> ...



For what it's worth, I just lifted an Eneloop AAA cell free of the negative tang on an 0FAB01 and an 0H0FA. In both instances, it actually lifted a few millimetres before it broke contact. Surprisingly, it took more movement to break contact on the most recent version. It has the little protrusion on the contact point I mentioned in post 368.

As you know, the wrapper of Eneloop AAA cell doesn't extend around the shoulder of the negative end of the cell, so there was little risk of tearing it.

I would suggest giving this a try if you're at all concerned that the negative tang on your MH-C9000 is not making adequate contact with your AAA cells. It will also provide a good indication as to whether you need to consider implementing the modification suggested by SilverFox in post 364.

It's definitely a shortcoming that MahaEnergy needs to rectify though. I'm actually surprised that it wasn't addressed when they modified the tang to add the little protrusion to the AAA cell contact point.


----------



## Bones

Turbo DV8 said:


> ...
> No shrink wrap, and I practiced far more effort than should ever be necesary to ensure good contact, and the chargers negative AAA contacts still only barely nip the gnat's-*** edge of the cells.
> ...



After deliberately popping an AAA cell free of the negative tang a number of times, I have come to believe that the problem your encountering is not caused by a poor contact.

Because the contact applies considerable pressure on the cell, it either makes what I would deem a good connection or the cell springs upwards and free. This is explained by the fact that the contact point is at the end of a downward angled bend in the tang as depicted in the image in post 368.

This may not be the case, however, in instances where a cell's wrapper extends around the negative end. The wrapper could definitely interfere with contact while preventing the cell from springing free.


----------



## SilverFox

Hello Black Rose,

If you look at the "Negative Tangs" picture that Bones posted, you will observe that the last section of the AAA position is pointed toward the base of the contact. 

If you start from the circuit board and go up to the first bend on the AAA contact, I simply straightened that bend until the next bend was lined up with the temperature sensors. This resulted in the flat between the two bends being almost horizontal, but not quite.

This results in moving the contact point from the edge of the AAA cell more toward the center of the cell. After unbending the first bend, the last section ends up almost pointing straight down toward the circuit board.

Tom


----------



## Black Rose

Got it. Thanks.

I captured this page as a web archive file so I don't lose it.


----------



## Turbo DV8

Black Rose said:


> When I put a AAA cell in, I put the negative end in first and the push the positive end in. I then roll each cell side to side to make sure it is deeply seated. When I use my C9000, I use the lift rod in the back so the charger is at an angle. Maybe that has something to do with it.


 
I do all these things, and still a few times both ROV Hybrid and Eneloop AAA's have ceased contact. I can imagine with the contact so on the gnat's-*** edge, it would only take a minute difference in manufacture/assembly to turn a bad example into one such as yours, which never gives problems. Wanna trade?:naughty:


----------



## Turbo DV8

Bones said:


> After deliberately popping an AAA cell free of the negative tang a number of times, I have come to believe that the problem your encountering is not caused by a poor contact.


 
Ahhh, quite easy to say without offering any other explanation why no other charger I have ever used has spontaneously lost contact with the negative end of a cell! ROV has no wrapper on the end. My cells require much, much less than a millimieter or two of lifting before losing contact. In fact, when they break contact, they are already so close to the edge of the cell, there is not even a "ping" or other easily discernible tactile return to indicate they have ceased contact, other than the cell suddenly becomes loose in the bay. Since I've had three La Crosse's apart to add filter caps on the PCB, I suppose I could bend the tangs on the C-9000, but I have to wear a disguise :santa: so nobody from Maha reads that I am voiding my warranty!


----------



## Turbo DV8

And yet another disheartening occurrence on both my Maha's tonight. I wanted to do a R&A on two remote control AAA cells, that had been charged a couple months earlier and don't see a lot of use, so I expected a considerable remaining capacity upon the initial discharge. Due to having two sets of three cells running on each charger, I used one slot on each charger for the two remote cells. After programming each cell to discharge at 400 mA, I noticed the display did not cycle through the four displays, but instead went straight to the next cell after indicating voltage, and thereafter did not recognize anything in that slot. At first I thought, "Here we go again with the crappy AAA cell contacts." This happened on both chargers, multiple tries, until I noticed that the indicated voltages were between 0.93 and 0.99V. But unlike prior experiences with premature terminations, the display did not say DONE, it just went to the next slot. Finally, I realized my old nemesis, premature termination, was rearing it's ugly head again, and on both chargers.

Now, I suppose some will say if it happened on both chargers, it must be the batteries, but at the risk of repeating myself from my first rounds of premature termination, "There ain't a damn thing wrong with the cells that should make the C-9000 unable to initiate or complete a discharge." Out of desperation I put the cells on my reliable La Crosse and did a discharge at 500 mA, and they both returned over 600 mAh of capacity, which is about what I would have expected to see knowing when they were charged last and how much use they had in 2 months in the remote. When inserted in the La Crosse, the voltages were 1.18V and 1.16V. I don't nurture junk cells in my collection, and I have no doubt the cells would have powered an application with higher drain than a remote just fine. The C-9000 just decided it didn't want to discharge the cells tonight. Sorry to vent, but man, almost every day now it seems the C-9000 stumbles on a simple task the La Crosse wouldn't even bat an eyelash at. What's really eating at me is I don't have much :hairpull: left to pull! I felt young and vibrant, and had long flowing locks, before I bought the C-9000's!


----------



## Mr Happy

Ah, fickle human nature. The BC-900 lies and the C-9000 tells you the truth, but you prefer to hear the lies :kiss:


----------



## H.Roark

Turbo DV8 said:


> What's really eating at me is I don't have much :hairpull: left to pull! I felt young and vibrant, and had long flowing locks, before I bought the C-9000's!



Um, maybe you should just sell the Maha's? It seems to not be a match made in heaven. 

I like mine, but I am new to rechargables and most of my cells are new, or have few cycles.


----------



## Turbo DV8

Mr Happy said:


> Ah, fickle human nature. The BC-900 lies and the C-9000 tells you the truth, but you prefer to hear the lies :kiss:


 
Try this out for size, and tell me the Maha "tells the truth"... After discharging the two AAA cells on the La Crosse last night, I set them up for a R&A at 500 mA charge and 200 mA discharge, one cell in each charger. This morning, both said DONE. But one unit had again miraculously switched overnight from R&A mode back to charge mode. From an earlier post, you'll recall this is not the first time a unit did this. There was no power interuption, as the other charger did not switch to charge mode. But I'll tell you what the other charger _did_ do. Although it was still in R&A mode and said DONE, it said the capacity of the cell was 69 mAh. :thinking: That's not "telling me the truth." That's just pure bullcrap. :thumbsdow I put both cells back in the LaCrosse and discharged at 500 mA and both cells returned over 700 mAh. One could debate the effects of whether the C-9000 measures voltage under load, or the La Crosse measures it between load pulses, but there's just no way to give the C-9000 the benefit of the doubt when I take known decent cells and the Maha says a cell only delivers 69 mAh under a 200 mA load, while the La Crosse indicates over 700 mAh under a 500 mA load. I don't consider missed charge terminations, premature charge terminations, premature discharge terminations, sporadic results from poor contacts, the unit spontaneously switching modes overnight, and plain flat-out BS capacity results to be "truthful." But if you still do, you are welcome to buy my truthful C-9000's for $35 each, plus shipping cost, if TD doesn't take them back.

H. Roark, you are correct. I am going to call Eugene and see if I can sell my units back to TD.


----------



## jhellwig

Not to sound rude but did you ever think that since you are the only one whining about this problem that you might just have a bad charger. Either that or you consistently keep doing something wrong. Usually when a person get mad at something and thinks its junk when they are just doing something wrong there is no amount of stamping your feet and crying that is going to change it. I've done the same thing several times. Getting mad about it is just going to result in getting madder and accomplishing nothing.


----------



## Turbo DV8

jhellwig said:


> Not to sound rude but did you ever think that since you are the only one whining about this problem that you might... consistently keep doing something wrong?


 
:welcome: 

Yep, that's it. I'm a completely moronic idiot. Forty-two years old with a college degree in electronics, and in two months I haven't been able to figure out how to use a battery charger. Now why didn't I think of that?:thinking: Thanks for helping me see this from the logical perspective...


----------



## jhellwig

Forgive me for thinking that maybe since you keep having the same problem on different chargers that no one else seams to be having you could possibly be doing something wrong. How silly. 

Either you have two bum chargers or you are doing something wrong. Everyone else seamed to figure it out.

I've seen it time and time again. "I've been doing it this way for 40 years." It doesn't mean that you can still do it that way and it doesn't mean that it was right in the first place.


----------



## Lite_me

Turbo DV8:
I saw in another forum here that you also had an HD TV go out, and deemed unrepairable, after only 13mo. I'm wondering if you might have some sort of AC problem. Just a thought.


----------



## Turbo DV8

Lite_me said:


> Turbo DV8:
> I saw in another forum here that you also had an HD TV go out, and deemed unrepairable, after only 13mo. I'm wondering if you might have some sort of AC problem. Just a thought.


 
Man, now I got bugs crawling on my monitor! 

No, the defect in my TV is widespread across the Panasonic 6, 7 and 8-series plasmas, and doesn't rear it's ugly head until after about a thousand hours of use, then gets worse, and there is no repair. Google "Panasonic purple snake(s)"


----------



## Lite_me

Sorry to add to your problems. 

I had a quick look at the Panasonic problem. That's a real bummer. Although costly, Panasonic should make it right. 

Ok, back on topic - I can't help ya.


----------



## Marc999

Hey guys, I just got my c9000 in the mail today and put Powerex 2,700 batteries through a 'discharge' cycle @ 700 ma.

Perhaps I'm not understanding the results:

Slots 1-4 Voltage: 1.18,1.17,1.14,1.10
Slots 1-4 Mah: 896,971,2080,2122.

Seems too coincidental that I aligned the 4 batteries in order from lowest to highest capacity remaining. What am I not understanding here? If it helps to know, I have recharged these batts. in the Mh-C204w [charges in pairs] almost 2 weeks ago and left them idle until today's discharge.

They are currently undergoing 'break-in' mode.

thanks,
Marc

Edit.....oh, I spoke too soon: charging in pairs on the c204w resulted in varying total capacities between the 2 pairs. One pair either didn't charge completely or is discharging much quicker than the other pair. Is that sort of right?


----------



## Bones

Marc999 said:


> ...
> Edit.....oh, I spoke too soon: charging in pairs on the c204w resulted in varying total capacities between the 2 pairs. One pair either didn't charge completely or is discharging much quicker than the other pair. Is that sort of right?



Hi Marc999,

It could also be that one cell in the pair was left undercharged as postulated in this thread by SilverFox:

http://www.candlepowerforums.com ... post2778384

Now that you can performance match your cells with the MH-C9000, you may also find this post helpful:

http://www.candlepowerforums.com ... post2804079
.


----------



## Marc999

Hey guys, I just completed my first Break-In on the mh-c9000 [0H0BB] with Powerex 2,700. 

I began with a 'Discharge', prior to Break-in. The Break-in process took 39 hrs. to display 'Done', at which point the readings are 2480,2497,2476,2553 mah, with voltage at 1.47.

I thought with the Break-in mode, that voltage cutoff @ 1.47 isn't considered?

Marc


----------



## SilverFox

Hello Marc,

During Break-In, maximum voltage is not a criteria for terminating the charge. 

After a Break-In, it is not unusual to see voltages in the 1.47 volt range.

Tom


----------



## Marc999

Alright, thanks Tom.

I noticed this charger really packs batteries in tightly, which is nice...but, I really have to pry them out resulting in torn wrappers/small dents at the -ve end. Hopefully not a big concern.

Marc


----------



## Mr Happy

Marc999 said:


> I noticed this charger really packs batteries in tightly, which is nice...but, I really have to pry them out resulting in torn wrappers/small dents at the -ve end. Hopefully not a big concern.


Are we talking about the same C9000? Compared to other chargers the C9000 puts huge amounts of space around the batteries making it easy (OK, less hard) to remove them. 

To remove a battery cleanly, grip it tightly at the positive end, push it back firmly towards the negative end, and lift the positive end up and out.


----------



## Marc999

Yes, we're talking about the same charger. There is lots of space b/w batteries, yet I wouldn't say it's a piece of cake to remove them.

I tried your suggestion; I do have to exert a fair amount of pressure, pushing towards negative end, while lifting up/out positive. Works fine. Better than my initial pulling batteries up/out by neg.end.


----------



## Bones

Marc999 said:


> ...
> I tried your suggestion; I do have to exert a fair amount of pressure, pushing towards negative end, while lifting up/out positive. Works fine. Better than my initial pulling batteries up/out by neg.end.



The negative tangs on the MH-C9000 are quite stiff when new, but they do become more elastic with use. You can accelerate the process by deliberately flexing them. I found that a length of 1/4" wooden dowling left over from some project worked quite well for this purpose. It fit into the opening for the tang and didn't slip off when pressure was applied.

Take note that only the negative tangs are designed to flex. The postive are actually fixed in place:

http://www.candlepowerforums.com ... post2810241
.


----------



## Marc999

Thanks Bones. It's already becoming easier to pull them out. I tried it a few times and the -ve end is more flexible now.

Re: Powerex 2,700 that I've had for about a yr. I've put them through a discharge, Break-in, discharge, R&A, discharge.[1,400ma/700ma] The Break-in resulted in cells hovering close to 2,500. The next disch/r&a/disch each resulted in progressively lower readings. Currently around 100 ma less on average from the initial Break-in. 

The instructions for poorly performing cells say to do a refresh 1-3 times, followed by break-in. Then repeat break-in 1-3 times if capacity increases by at least 10%. 

Should I follow these directions or just go ahead and do another break-in at this point? Also, am I just wasting time doing a discharge if my intentions are to do more r&a or break-in?

thanks,
Marc


----------



## Hoggy

Marc999 said:


> Re: Powerex 2,700 that I've had for about a yr. I've put them through a discharge, Break-in, discharge, R&A, discharge.[1,400ma/700ma] The Break-in resulted in cells hovering close to 2,500. The next disch/r&a/disch each resulted in progressively lower readings. Currently around 100 ma less on average from the initial Break-in.



If they're 2700's that are reporting as 2500's - I'd say stop.
You've fully refreshed those cells to their maximum! (Especially considering you started getting lower capacity readings.)

It's not likely they all came in at 2500 when you first bought them - before you had a way of measuring things and didn't know any better.

I'd say, take that 2500 and run with it! Use them now.


----------



## Marc999

Hoggy said:


> If they're 2700's that are reporting as 2500's - I'd say stop.
> You've fully refreshed those cells to their maximum! (Especially considering you started getting lower capacity readings.)
> 
> It's not likely they all came in at 2500 when you first bought them - before you had a way of measuring things and didn't know any better.
> 
> I'd say, take that 2500 and run with it! Use them now.



Hi Hoggy, 

Good plan, yet for curiosity/understanding c9000 sake, I continued to do yet another R&A, followed by discharge.[this time at 600ma rather than 700ma]. Once again, cells dropped by a further 100 ma. Now all are residing between 2200-2300 mah. This process began with a Break-in, and 2 R&As with discharges in between/after each. 
Why am I seeing such considerable drops between each R&A and discharge? 

Marc


----------



## Mr Happy

What capacity did the R&A give compared to the discharge? Did the capacity drop every time?


----------



## Marc999

Not at my place at the moment, but I do have the figures recorded that I can post later.

I have done the following thus far: discharge, Break-in,discharge,R&A,discharge,R&A,discharge. The highest figures I had seen were due to the Break-in. Each successive discharge,R&A resulted in lower capacities from the previous R&A, or discharge. Considering the powerex 2,700 batteries are at best a yr. old and haven't been charged more than 5-6 times on my c204w, I'm at a loss to understand why i'm seeing such capacity losses with each R&A and/or discharge. Whatever I do at this point seems to create a downward spiral for these batts. So, yes...a capacity drop each time. 
If it's of interest I was using 1,400ma for charge/700 ma for discharge, with the exception of the last discharge where I used 600ma.
Any thoughts?

Marc


----------



## Mr Happy

Well the capacity of a battery is not a fixed number, but depends a bit on how it is measured. The break-in process always leads to higher capacity measurements than the R&A process. So you should definitely expect R&A to show lower numbers. Overall I would not worry too much and would follow the advice of others to just go ahead and use the batteries.

It may also be that by cycling the batteries like you are doing you are improving their performance and increasing their voltage. Ironically this would reduce their apparent capacity as the C9000 cuts off at a max charging voltage of 1.47 volts. If the max voltage is reached sooner the batteries will be charged less fully before the discharge. If you want the maximum charge you should also be sure to keep the batteries on the charger for 2 hours after Done appears so they get the full top-off charge.

There is nothing wrong with using 1400 mA for charging, but I tend to use 500 mA for discharging just for consistency. It won't make a big difference though, it is just a matter of preference.


----------



## jhellwig

Mine was doing the same thing also till about 6 cycles before it evened out. IT didn't matter what kind of batteries I used either


----------



## crofty

I`ve also seen a drop in reported capacity when doing back to back cycles.

It doesn`t happen when letting the cells rest for a while between cycles though, I think they benefit from a bit of a rest.

This is just my observation though, nothing scientific.


----------



## Russel

Marc999 said:


> ... Whatever I do at this point seems to create a downward spiral for these batts. So, yes...a capacity drop each time.
> If it's of interest I was using 1,400ma for charge/700 ma for discharge, with the exception of the last discharge where I used 600ma.
> Any thoughts?
> 
> Marc


 
Have you tried two or three break-in cycles in a row?

Russ


----------



## sygyzy

I have the predecessor to this charger. Can this model "jumpstart" an adjacent cell? You know, the trick where you put a dead cell next to a live one, use a wire for 10 seconds, then plug in the charger? I don't see why this couldn't be a built in function.


----------



## Marc999

Nope, I haven't tried 2 or 3 back to back 'break-ins' with the powerex 2,700s. As others mentioned, I decided not to get my boxers in a knot over the slightly lowered capacity during repeated back to back 'refresh/analyze, discharge'. I ended up just using the batts. and they've been fine re: run time. I agree with others that I didn't allow for a long enough rest between cycles. Voltage never got a chance to settle down and kept terminating prior to expected capacity. 
All the year 2006 eneloops I have, are breaking-in around 1900+, which meets the minimum capacity and puts a smile on my face. I'm currently breaking in some year 2008 president's choice 'ready to use' batts. [supposedly eneloops]. I'll be curious to see the results. 

Thanks guys, and welcome to the spring season.

Marc


----------



## Russel

So far, running Eneloops through the C9000 break-in cycle with default 500ma discharge.

Average capacity of 12 2006 code date Eneloop AA cells: 1929.25mah
with none falling below 1900mah.
ID size C C measured
9	AA	2000	1944	-2.80%	06-08 T3
10	AA	2000	1940	-3.00%	06-08 T3
11	AA	2000	1905	-4.75%	06-08 TT
12	AA	2000	1944	-2.80%	06-08 TT
13 AA	2000	1927	-3.65%	06-08 T4
14	AA	2000	1959	-2.05%	06-08 T4
15	AA	2000	1923	-3.85%	06-08 TL
16	AA	2000	1905	-4.75%	06-08 TL
17	AA	2000	1917	-4.15%	06-08 T2
18	AA	2000	1970	-1.50%	06-08 TT
19	AA	2000	1900	-5.00%	06-08 T2
20	AA	2000	1917	-4.15%	06-08 T4



Average capacity of 4 2008 Eneloop AAA cells: 796.5mah
ID size C C measured
1	AAA	800	803	0.38%	08-04 OC
2	AAA	800	793	-0.88%	08-04 OC
3	AAA	800	794	-0.75%	08-04 OC
4	AAA	800	796	-0.50%	08-04 OC


----------



## tnuckels

We have a fairly large inventory of Duracell and Energizer rechargeable AAA and AA batteries and almost all of them are NOT the newer L)ow S)elf D)ischarge type. I recently bought a few packs of the LSD batteries and like them well enough to decide that any new purchases will be LSD from here on out. 

In order to better understand my current inventory and weed out any weak or defective batteries to make room for the newer LSD batteries, I bought the MAHA / Powerex MH-C9000 Wizard One Charger-Analyzer and am currently running all the batteries I can find through the Refresh / Analyze process.

My question is this: Is there any consensus on what constitutes a battery that needs to be recycled, like perhaps a % drop in capacity?

Some of my older cells are down 25 – 30, even 50%. I might spend some time trying to revive the more promising ones and know there is a point of diminishing returns somewhere in this process, I’m just not sure where it is.


----------



## SilverFox

Hello Tnuckels,

I recycle cells when they drop below 80% of their initial capacity.

Tom


----------



## tnuckels

Hi Tom,

Thanks for your insight here. Would you be using mAh stated on the battery’s label as a starting point, or capacity that you’ve marked somewhere after a run through the Break-In sequence?

I really like this charger for the flexibility each bay has and extra information it gives you, but see a potential pitfall in that I don’t want to make a career of battery maintenance. We’re still running the machines and not visa-versa … right?


----------



## Alan B

I have both the C9000 and the Lacrosse BC-900. I wish the C9000 had the nifty "cycle each cell until it stops improving" mode of the BC-900. That makes it easy to bring a cell up to the max it is going to get to, and then you can decide if that's good enough.


----------



## pobox1475

> the nifty "cycle each cell until it stops improving" mode of the BC-900. That makes it easy to bring a cell up to the max it is going to get to,


Interesting. I have a C9000 and thought _it _covered all the necessary bases.


----------



## SilverFox

Hello Tnuckels,

In most cases the initial capacity is a little less than the labeled capacity. If you don't have records of what the initial capacity was, you could probably go with 90 - 95% of the labeled capacity as a starting point.

Tom


----------



## tnuckels

Thanks again Tom.

I had spent a fair amount of time reading up here on CPF on the two leading chargers: the BC-900 & C9000 and thought there was a fairly strong leaning here toward the C9000. I did not, however, take the time to read through the user’s manuals, which I will usually do if they are available online.

An automated refresh sequence that runs as long as progress is still being made, then cuts off, sounds like a very useful feature. No need to keep up with the results of each sequence; more time to loaf off.

Doh! Does the list of things I need, that I didn’t know existed pre-CPF, never end?


----------



## Mike89

Since William came in here from Maha, I have a question for him. Is there any new Maha chargers on the drawing board? Actually surprised no one asked him that question as we are always looking for new stuff.


I wonder if Turbo ever exchanged his C-9000s (or got rid of them altogether). He was pretty vocal in not liking them much. 


I recently ordered both. I'm a newbie in the rechargeable battery world (I've been reading my *** off lately in this forum to get up to speed) and am looking forward to see what my take is going to be down the road with these two chargers.

My impression so far of the rechargeable world. I have become quite intrigued with all the information (a lot more than I would have thought possible). Seems this is not for the faint of heart or for those that do not like to tinker (fortunately, I am neither of those). Quite a different routine than using disposable primaries. I suspect it's going to be quite interesting.


----------



## Turbo DV8

Mike89 said:


> I wonder if Turbo ever exchanged his C-9000s (or got rid of them altogether). He was pretty vocal in not liking them much.


 
I got rid of them. Mine were far too finicky and inconsistent.


----------



## Mike89

Whatever charges your boat man. To each his own charger. I got my C800s and BC900 today and have been playing around with them. The C800s is good in that it can charge 8 batteries. It's a pretty basic charger with not much user configuration. The BC900 is ok so far but a little figgity with the controls. Still trying to get the hang of it. I don't really like that it can't do a stand alone discharge (without charging back up again). The C800S can't either (and the C800S doesn't give any comparitive information on how close the batteries are to each other, just lists them as Done). Should have my C9000 in a couple of more days. Don't hold me to this quite yet (since I don't actually have it yet) but I have a feeling that I'm going to like the C9000 better than the other two. I think it's going to have more of the options/configuration I'm going to want and would use the most (and the "Break In" mode pretty much sold me). I don't plan on really doing any 200 mah charging as I don't particularly think that's really good for the batteries. So I doubt this termination thing is really going to come into play for me. I plan on using all 3 as I like to use what I spend money on. 

Time will tell which one will be my main.


On a side note. 4 Lacross 2600 mah AA and 4 Lacross 1000 mah AAA batteries came with the BC900. I'm giving them a go in both chargers to get the hang of this charging thing but I think the batteries (especially the AA ones) are bad. The readings are all over the place, 2 of them less than 50% of the other two, and the other two still well below rated mah. I'm still playing around with them, running them through all the options to make sure. I think I'm going to end up asking Thomas Distributing if they will send me some more free unless these chargers really can bring them back from the dead.

Might as well ask a rookie question while I'm spouting off here. I did a discharge and charge of all 4 AAs on the BC900 (when doing this, one of the batteries switched over to "charge" in about 1 minute, the other 3 over an hour). When they were all done, I cycled through the Display button to get to the mah. Now I assume what I was looking at was the capacity from the discharge and not what was put into them (as I know the two are different)?

Anyway the mah was something like 1156, 1103, 1469, 237 (which I guess is 2370). Kind of all over the place. I'm currently running them though a Refresh to see what happens but it seems right now I only have one decent one out of the four. I think those batteries must be really old.


----------



## SS-3

Hi, I'm newbie to chargers other than my experience with charging NiCad packs for RC cars over a decade ago. I chose the MH-C9000 over the LaCrosse BC-900 and hopefully I made the right choice. I purchased my MH-C9000 from Thomasville and it should be here in a few days. I have a couple of questions that I hope someone on here can answer.

1) I purchased two four packs of the Sanyo Eneloop 2000mA batteries. Should these batteries go thru the break-in cycle or can I just charge them normally?

2) Maha and Thomasville recommend charging these at 1000mA and no less then .33 which would be 660mA, round up to 700mA. Should I charge at 1000mA or 700mA in regards to battery longevity? I believe the default on the MH-C9000 is 1000mA from the reading I have done.

3) The online manual from Maha and Thomasville is really light and not in-depth. Is there a more in-depth manual around or an area of this thread that provides greater detail or do I just have to read thru this forum for more information.

FYI... This is my first post on this board, I'm a new member.


----------



## SilverFox

Hello SS-3,

Welcome to CPF.

Your Eneloop cells will most likely work just fine if you simply use them. On the other hand, if you want the absolute most from them and have some extra time, do a discharge followed by a break-in.

The default 1000 mA is a very good rate to charge your cells.

You may want to do a search in the reviews section of CPF for an in depth review of the C9000.

Tom


----------



## Turbo DV8

SS-3 said:


> I purchased my MH-C9000 from _*Thomasville*_...


 
Wow, Thomas Distributing is getting _big... really_ big!


:welcome:


----------



## Ditmanw

Hi All

I have been having a read of this forum and have to say is most informative.

I am the proud owner of a brand new MH-C9000 and am having problems understanding the settings.

My main question at the moment is when putting cells in for Refresh and analyze there are 2 settings and I am not sure if I am setting them correctly based on the manual.

First setting is charge rate. (please set me straight if I am reading this all wrong) I have a 2200Mah x .5 = 1100 manual say between .3 and 1.0) for my charge setting and I am leaving discharge rate at default. Am I getting it right or should I charge at a higher or lower rate ?

Thanks in advance.

Lawrie


----------



## Black Rose

A charge rate of 1000 or 1100 mA (close to 0.5C) is fine for a 2200 mAh cell.

The 500 mA discharge rate is also fine....that's what I normally use for all my cells in the 2000 - 2100 mAh capacity range.


----------



## TakeTheActive

Ditmanw said:


> ...I am the proud owner of a brand new *MH-C9000* and am having problems understanding the settings.
> 
> My main question at the moment is *when putting cells in for Refresh and analyze there are 2 settings* and I am not sure if I am setting them correctly based on the manual.
> 
> *First setting is charge rate.* (please set me straight if I am reading this all wrong) I have a 2200Mah x .5 = 1100 manual say between .3 and 1.0) for my charge setting...


The Industry Recommended Charge Rate is 0.5-1.0C. Thus, for 2200mAh cells that's 1100-2200mA. IMHO, most *Newbies* 'overthink' things and then get nervous looking for 'Hard-and-Fast' Rules. Instead, look for GUIDELINES, experiment, and then choose what works best for you / you like. 

Personally, before I found CPF, I often charged at 200mA (with my La Crosse BC-900) and did quite a bit of damage to my rechargeable battery collection (i.e. unrealized missed terminations on ~50+ Rayovac 1300mAh and/or 1600mAh HSD NiMH cells). Before the BC-900, I used a Rayovac PS1 (~200mA) and then a Rayovac PS3 (~500mA). Since the PS3 got my cells pretty hot and the PS1 didn't, I (incorrectly) chose 200mA for the BC-900. Now, with my Maha MH-C9000 and it's wider channel spacing, I charge my 'newer' LSD and 'older non-CRAP' HSD cells at as high a rate as possible between 0.5 and 1.0C without generating excess heat (measured 'somewhat inaccurately' with an old RadioShack Indoor/Outdoor Thermometer - i.e. if 1.0C gets the cell over 120°F, next time I'll lower it to 0.75-0.80C and monitor the temperature again).

CLICK on my Sig Line LINK and you find PLENTY of 'Charge Rate' articles in the first section '*Rechargeable Battery*'.



Ditmanw said:


> ...and *I am leaving discharge rate at default.* Am I getting it right or should I charge at a higher or lower rate ?


For Discharge Rate, I always use 0.2C for '*Standardization*', i.e., when you run a 'Break-In' cycle on the MH-C9000, it charges at 0.1C and discharges at 0.2C. Since I record those numbers, I like to also compare 'Apples-to-Apples' when I run a 'Refresh-and-Analyze' or 'Cycle' cycle.

My observations show:
LOW Discharge Current -> HIGH(er) Cell Capacity
HIGH Discharge Current -> LOW(er) Cell Capacity
Again, not a 'Hard-and-Fast' Rule - just a choice I made.

You made a good purchase. Invest a few hours 'Reading-and-Learning' about proper 'Care and Maintenance' and then have fun!


----------



## Ditmanw

Thanks for the replies I am starting to feel a little more comfortable with the charger now.

I am taking all the advice and will have a good read over the weekend.

I have been using some old batteries to test out all the functions and have been very supprised with some of the results. Batteries I thought only good for the bin have a new limited lease on life.

Again thanks and I will keep an eye on the forum as there is a huge amount of Information and experince here. Glad I found the forum.


----------



## hydrazoon

my c9000 has just gone wrong after 2 years of faithful service. After charging some AAA's at 700 mA, slot 2 still thinks it has a battery inserted. I power it up empty and the arrow goes straight to slot 2 and waits for me to select a mode (which I can) if I don't it defaults to charging.

Anyone else experienced this problem? 

I presume it's a warranty job unless any of you have a solution.


----------



## TorchBoy

hydrazoon said:


> Anyone else experienced this problem?
> 
> I presume it's a warranty job unless any of you have a solution.


Yes, I had that happen to one of mine (and I think it might have been slot 2 that failed).

Yes, it's a warranty job.

And in case no one has said it yet, :welcome:


----------



## bcwang

There are a lot of posts on the C9000 and so far I haven't found any solid conclusion to this issue.

Why does the original C9000 give higher mah readings in "refresh and analyze" than the newer version? I see about 100-200mah difference going from the older version to the newer version.

-Is it because the charge isn't as complete? I kinda thought the 2 hour rest pause does include a 100ma top off to compensate for that.

-Is it because it now measures voltage under load stopping at 0.9v instead of voltage with no load stopping at 1.0v? This would really lower read capacities on some cells because this charger uses a pulsed load of 1amp even if you set the discharge to 100ma. This can't be a good way.


Another interesting issue:
I have some powerex 2500 cells that were sitting around a while. I charged them up in my 808m and proceeded to test using discharge on the C9000. They all instantly terminated. Voltage still around 1.4+. Then I set the discharge voltage to 100ma, and they all terminated pretty much instantly. I later set them to "test" in my bc900 and the next day they showed around 2amp/hr capacity.

So basically the problem is with cells in bad condition, I can't really condition the cells in the C9000 because they fail to discharge properly. If I can't discharge them I can't refresh them into a good state or test them for actual capacity at a 0.2c discharge rate. Luckily I have many chargers to pick from to do my deeds.

Improvements I'd ask for:
-Constant current discharge for measuring capacity, with a 0.9v cutoff under that constant load. Maybe the pulsed type discharge can be a special mode as it might be beneficial for certain refresh type applications. But it needs to not be the only mode as some batteries cannot take high load even if the capacity is good still.
-Charging seems fine, I'd like an indicator to let you know it's in top-off mode so you know when it's fully done when that goes away. Another way would be to show the top-off current instead of 0ma. Would also be good to show the trickle current, better to be truthful and accurate rather than hide this from the user.
-The high pitched sound is what keeps me from using this charger more, please use parts that don't switch in the hearing range. I was extremely annoyed by it at first but now I can't hear it as much, I wonder if it already destroyed my hearing at that part of the spectrum. But my wife still hears it from clear across the room and forced me to use this thing in another room which is rather inconvenient.


----------



## Mr Happy

If charged cells terminate instantly on discharge, even at 200 mA, then it is a sign the cells need reconditioning. They probably will have a large voltage depression on a real load too. Try running a break-in cycle on them. I had some eneloops that did the same thing once and a break-in cycle fixed them right up.

In general the discharge function seems to be quite accurate. I just finished running some new 800 mAh AAA Hybriloops through a break-in cycle and the reported capacities were all about 815 mAh.

I think the charge is less complete with the newer C9000 versions. On the other hand the cells never get warm at all, even when charged at 2000 mA. That's a reasonable trade-off for me.


----------



## bcwang

But it seems unwise to break-in a fully charged cell with no way to discharge it first on this charger. In fact, I wonder what would happen, maybe that 16 hours will overcharge the cell damaging it even more, then upon discharge it'll immediately terminate because it's in even worse shape, and then begin the second 16 hour charge. Yikes!


----------



## Black Rose

bcwang said:


> But it seems unwise to break-in a fully charged cell with _no way to discharge it first on this charger_.


That's what the discharge mode is for 

I know what you are referring to....it would be nice to have a mode (or a configureable option) that would automatically do a discharge and then go into the selected charging mode.


----------



## Mr Happy

bcwang said:


> But it seems unwise to break-in a fully charged cell with no way to discharge it first on this charger. In fact, I wonder what would happen, maybe that 16 hours will overcharge the cell damaging it even more, then upon discharge it'll immediately terminate because it's in even worse shape, and then begin the second 16 hour charge. Yikes!


It shouldn't hurt, but if you're worried try running just the first 6 hours of a break-in charge and then manually interrupting it before trying a discharge again.

You might want to be conservative about the entered capacity too. Start with 2000 mAh instead of 2500 mAh until you know what the real capacity is.


----------



## bcwang

Black Rose said:


> That's what the discharge mode is for



I guess you missed my original post. Because the discharge uses pulsed 1amp, some of my batteries in poor shape terminated discharge right away even though they were fully charged, even if I set it at 100ma.


----------



## TorchBoy

bcwang said:


> Why does the original C9000 give higher mah readings in "refresh and analyze" than the newer version? I see about 100-200mah difference going from the older version to the newer version.


The C9000 (now) discharges at a pulsed 1 A, right?

When the first model discharged a cell it used to ramp down the current draw as the cell flattened (the onscreen figure, anyway) so a discharge could take hours longer than it should. That sucking the last bit of capacity out could account for some of the difference. I think the effect was especially with low quality cells.


----------



## digitor

TorchBoy said:


> The C9000 (now) discharges at a pulsed 1 A, right?
> 
> When the first model discharged a cell it used to ramp down the current draw as the cell flattened (the onscreen figure, anyway) so a discharge could take hours longer than it should. That sucking the last bit of capacity out could account for some of the difference. I think the effect was especially with low quality cells.



This effect was because in the earlier versions the voltage was measured off-load, and the charger can't maintain its programmed discharge rate with a cell voltage of less than 0.9V.* The voltage would bounce back during the measurement, so the discharge would continue. Newer models measure the voltage on-load, so this does not occur any more. 

Cheers


* See first post of this thread


----------



## TorchBoy

digitor said:


> This effect was because in the earlier versions the voltage was measured off-load, and the charger can't maintain its programmed discharge rate with a cell voltage of less than 0.9V.* The voltage would bounce back during the measurement, so the discharge would continue. Newer models measure the voltage on-load, so this does not occur any more.
> 
> Cheers
> 
> 
> * See first post of this thread


Hm, so of course it would be more pronounced with bad cells. I probably knew that once, too. 

The first post of this thread doesn't say much at all.


----------



## digitor

TorchBoy said:


> The first post of this thread doesn't say much at all.



Yes, you're right - in my enthusiasm I got that wrong - it's the second post 

Cheers


----------



## SilverFox

Hello Bcwang,

I happen to think that even the current version is a little optimistic in reporting cell capacities. It's just that the original version was a little more optimistic... 

However, both are close enough for general use, and the current version is actually pretty close to what you see with dedicated battery testers. 

I believe the difference has to do with the termination of the discharge. The original version terminated on unloaded voltage, and the current versions terminate on voltage under load. Maha attempted to compensate for this difference by terminating at a higher voltage with the earlier version. While close, there is still a small difference between unloaded voltage and loaded voltage even when you try to adjust for the rebound factor.

With your 2500 mAh cells, the C9000 is telling you that you have crap cells because they are unable to hold voltage under load. While it is true that the C9000 pulses 1 amp at a duty cycle, keep in mind that the BC-900 also pulses its discharge. I don't recall what the actual discharge rate is, but I believe it is 0.5 amps.

Since you were able to discharge the cell on the BC-900, I would expect that a discharge graph would show that you would have a mid point discharge voltage of around 0.95 - 1.0 volts at a discharge rate of 100 mA. Once again, and indication of a crap cell.

Since you have a couple of strong indications that the cells are crap, you can now proceed to do a Break-In cycle on them. It doesn't matter that they are already charged. It is better if you discharge then first, but with crap cells it really doesn't matter all that much. When you do the Break-In you should find that the capacity is very low and this will be a final confirmation that your cells are crap.

Now you have to decide what you are going to do with the cells. I recycle them and move on. Others believe that as long as you can measure a voltage on a cell, it has to be good for something, and they set out to figure out an application that they can use them in. A problem with this is that once a cell craps out, it continues to degrade at an advanced rate. You continue to have problems and chase them until you finally replace the cells. I don't enjoy this level of frustration, so I test cells and recycle them when they crap out.

I would welcome the improvements you suggest, but don't know if Maha can incorporate those improvements and keep the price as low as it is. While there are a few of us that are more interested in quality and advanced features, there are still many that place the most significance on price. It will be interesting to see if Maha introduces another version of this charger.

Tom


----------



## TakeTheActive

*Does the C9000 top-off in R&A mode?*

Per *Re: Does the C9000 top-off in R&A mode?* by *bcwang*, I recently re-read many of the posts in this thread from Jan 2009 relating to his question. Referring back to the following two:


Black Rose said:


> Williams response didn't seem to directly answer the question you had about what happens in the rest periods.
> 
> I believe the top off charge is only applied after DONE is displayed, so it would not be applied at the 2 hour rest period following the first charge in R&A mode.
> 
> *SURVEY SAYS: WRONG*





Mr Happy said:


> *The top off charge is applied during the two hour rest period after charging in Cycle mode*, so I think it likely it is applied during R&A mode too, but I have not used R&A mode to find out for sure.



Where is the supporting documentation?
Was a DMM used?
If not, possibly someone like *Black Rose* (who has Rare earth magnet / alligator clip jumpers) would volunteer to take some measurements. 
The following statement contradicts the current printed manual:


willchueh said:


> 2-Hour top-off charge is applied in all modes *except in DISCHARGE and BREAK-IN*.
> 
> William





MH-C9000 Manual said:


> _9. When the program for a slot is completed, DONE will be displayed to the right of the bank number. With the *exception of DISCHARGE* mode, topoff charge and trickle charge (continuous) will be applied._


----------



## TakeTheActive

bcwang said:


> ...Why does the original C9000 give higher mah readings in "refresh and analyze" than the newer version?



Don't forget about the decrease in MaxV to 1.47VDC resulting in the observation that most cells now terminate on MaxV instead of -DeltaV.



bcwang said:


> ...*I have some powerex 2500 cells that were sitting around a while.* I charged them up in my 808m and proceeded to test using discharge on the C9000. They all instantly terminated. Voltage still around 1.4+. Then I set the discharge voltage to 100ma, and they all terminated pretty much instantly. I later set them to "test" in my bc900 and the next day they showed around 2amp/hr capacity.
> 
> So basically the problem is with cells in bad condition, I can't really condition the cells in the C9000 because they fail to discharge properly. If I can't discharge them I can't refresh them into a good state or test them for actual capacity at a 0.2c discharge rate. Luckily I have many chargers to pick from to do my deeds...



Please post the individual 'MH-C9000 Impedance Check' Voltages for each of these CRAP cells (Insert one cell at a time, press ENTER twice, write down the FIRST voltage displayed):
AFTER Discharging @ 100mA in your La Crosse BC-900
*DON'T LET THE AUTO-SWITCH TO CHARGE @ 0.9VDC RUN!*
.
AFTER Charging @ 1000mA in your Maha MH-C9000
Thanks!


----------



## bcwang

I took one of these crap cells, fully charged from the c204w.

impedance check 2.15v

Noticed when I did the 100ma discharge on the bc900 voltage is 1.42
When I did the same 100ma discharge on the c9000, voltage is 1.10

impedance check now 2.14v

So one, you can see the c9000 will terminate way before the bc900 will even with the same average current draw. It seems like the bc900 is constant current or much closer to it and would give a much more reliable discharge capacity if it only had a way to discharge and stop.

What this means is the c9000 is unlikely to do a good job getting all the energy out of aged batteries to do a good refresh job on it, yet those are the batteries in the need of a good refresh.

The CBA-II comes in handy for this situation, problem is the 1 cell at a time issue. I wonder how the other maha chargers handle their discharge techniques.


----------



## Mr Happy

bcwang said:


> What this means is the c9000 is unlikely to do a good job getting all the energy out of aged batteries to do a good refresh job on it, yet those are the batteries in the need of a good refresh.


When a cell is in such a bad way the break-in charge is the way to go; a refresh cycle is unlikely to make much improvement.

If you run your crap cells through a break-in cycle on the C9000 do they improve or do they remain high resistance?


----------



## 45/70

Just to throw in a little of my own experience in this situation.

When cells are this bad (ie. they won't discharge in the C-9000), *it is absolutely mandatory* _*to do a*_ _*slow discharge*_ before attempting the break in. You need to break up any crystallization in the cells, which I'm sure is present in this situation. The CBA is a great way to do this as well as discharge the cell, but as bc pointed out, it's takes forever. The BC-900 is a good alternative, as it pulses @ 500mA as opposed to 1000mA (sorry Maha). What I have done, is discharge the cells at 100mA in a BC-900. Pull the cells when the discharge stops. _Don't let them start to charge_! Give them a few minutes to recover and discharge them again. Repeat this at least a couple times.

When you're totally sick of this phase, or your patience runs out, whichever comes first , charge them on whatever charger will work, at 1C for *about 5 minutes*, let them rest a few minutes, then go back and do the discharge routine again. It doesn't hurt to repeat all this 2-3 times. After your final discharge*, then,* do a "break in" on the C-9000.

This is the only way I've found to do a proper break in on "crap cells". The theory is, if there are large crystalline formations in the cell when trying to form it ("break in"), the chemicals won't properly redistribute throughout the cell.

I've learned a lot about nickel based rechargeable batteries in the last 25 years. Most has been since I joined CPF, thanks in no small part to SilverFox and others on the Forums but,



SilverFox said:


> .....Others believe that as long as you can measure a voltage on a cell, it has to be good for something, and they set out to figure out an application that they can use them in. A problem with this is that once a cell craps out, it continues to degrade at an advanced rate. You continue to have problems and chase them until you finally replace the cells. I don't enjoy this level of frustration, so I test cells and recycle them when they crap out.



To a limited extent, I'm one of those "others". I use crap cells in wall clocks, LCD thermometers, and such with great success. They run devices anywhere from 3-6 months between charges and have done so for years after turning into "crap cells". I'll be damned if I'm going to put a brand new eneloop in them! :nana:

Dave


----------



## clintb

Wow, 45/70, all that in and out of the charger sounds like one heck of a mess. I submit to you something easier for single cell discharging. 

Viola!
http://www.integy.com/st_prod.html?p_prodid=1421&p_catid=199


----------



## 45/70

clintb said:


> Wow, 45/70, all that in and out of the charger sounds like one heck of a mess. I submit to you something easier for single cell discharging.
> 
> Viola!
> http://www.integy.com/st_prod.html?p_prodid=1421&p_catid=199



Agreed! If that unit worked with the cells in parallel, I 'd say it might be useful, however it states that a 4 cell charger is required. This suggests that one would use a hobby charger which would discharge the cells in series. That wouldn't be nearly as effective. The idea is to keep bumping each _individual_ cell down to it's lower limit to break up any crystallization. This just won't work as well if the cells are in series.

I want to point out that I don't use, and am not recommending anybody use the procedure I outlined in my previous post, _unless _you _really really _want to try to revive some cells. As Tom loves to frequently point out, crap cells are just that, crap cells, but if you want to try one more time, just to make sure, then go for it!

Dave


----------



## clintb

Ah, the craptastic Integy webpage strikes. That unit actually discharges the cells without the use of an external charger. It does, however, have a switch so that you can hook up a charger on the back and charge the four cells in series.

For discharging, power with a 12V power supply and insert the cells. It has a diode to keep the cell from going into reversal.


----------



## 45/70

clintb said:


> Ah, the craptastic Integy webpage strikes.



Good description! There certainly is (not) a wealth of information about the unit. I briefly looked at some of their other dischargers and was surprised to find some of them are recommended for NiMH cells/packs and have a 0.0 Volt cutoff. :thinking:

At any rate, that unit may do the job just fine. It's a bit pricey for something that, in my case, would rarely ever be used, if at all. Still, I guess if you were serious about reviving "crap cells" it'd be worth looking into. In the R/C world, of course, I imagine such units are quite popular.

OK, back on topic. 

Dave


----------



## bcwang

Mr Happy said:


> When a cell is in such a bad way the break-in charge is the way to go; a refresh cycle is unlikely to make much improvement.
> 
> If you run your crap cells through a break-in cycle on the C9000 do they improve or do they remain high resistance?



Finally finished running through my "crap" cells through a break-in. I discharged them all first, with one of the cells discharged through the CBA II at 2amp discharge using a cutoff voltage of like 0.2v. Watching the discharge, it immediately dropped down to like 0.5v, but slowly the voltage crept up to 0.9v and higher as it discharged. So something definitely was holding back the voltage potential that got better as power was pulled out of the cell.

Now this break-in with the c9000 might have done more bad than good, this is what happened.

-16 hours @250ma
-3 of the 4 cells on discharge was instantly done giving a reading of 0mah capacity. Only the one cell I did a high current discharge on gave a reading on the c9000, of around 1800mah (powerex 2500mah cell). 
-Then they all did another 16 hours @250ma

Ouch! that means 3 cells just got 32 hours of 250ma charging with no discharging in between which probably hurt them even more than before. I'm going to do the high drain discharge on them to try to revive them the way I did for the one cell. 

But this is one flaw I see on the c9000 that I hope gets addressed in future models. Pulse discharge with high amperage won't take enough energy out of the cell to condition them unless the termination voltage is revised. In my case, all 4 of these cells run great on the L1D on High for a long time, so they are very usable. If I just trusted the c9000 0mah capacity, I would have thrown them out. Now I have to re-evaluate a lot of cells I put in the "junk" heap since they actually might be ok still.


----------



## Mr Happy

bcwang said:


> Finally finished running through my "crap" cells through a break-in. I discharged them all first, with one of the cells discharged through the CBA II at 2amp discharge using a cutoff voltage of like 0.2v. Watching the discharge, it immediately dropped down to like 0.5v, but slowly the voltage crept up to 0.9v and higher as it discharged. So something definitely was holding back the voltage potential that got better as power was pulled out of the cell.
> 
> Now this break-in with the c9000 might have done more bad than good, this is what happened.
> 
> -16 hours @250ma
> -3 of the 4 cells on discharge was instantly done giving a reading of 0mah capacity. Only the one cell I did a high current discharge on gave a reading on the c9000, of around 1800mah (powerex 2500mah cell).
> -Then they all did another 16 hours @250ma
> 
> Ouch! that means 3 cells just got 32 hours of 250ma charging with no discharging in between which probably hurt them even more than before. I'm going to do the high drain discharge on them to try to revive them the way I did for the one cell.
> 
> But this is one flaw I see on the c9000 that I hope gets addressed in future models. Pulse discharge with high amperage won't take enough energy out of the cell to condition them unless the termination voltage is revised. In my case, all 4 of these cells run great on the L1D on High for a long time, so they are very usable. If I just trusted the c9000 0mah capacity, I would have thrown them out. Now I have to re-evaluate a lot of cells I put in the "junk" heap since they actually might be ok still.



You didn't need to run 16 [email protected] mA, you could have taken it more gently as I suggested above:


Mr Happy said:


> It shouldn't hurt, but if you're worried try running just the first 6 hours of a break-in charge and then manually interrupting it before trying a discharge again.
> 
> You might want to be conservative about the entered capacity too. Start with 2000 mAh instead of 2500 mAh until you know what the real capacity is.



Even so it is unlikely it did much harm, probably just failed to do much good.

I bet if you put a good cell in your L1D it would run brighter than one of these cells? Given the cost of that light I wouldn't devalue it by running crap cells in it.


----------



## 45/70

bcwang said:


> I discharged them all first, with one of the cells discharged through the CBA II at 2amp discharge using a cutoff voltage of like 0.2v. Watching the discharge, it immediately dropped down to like 0.5v, but slowly the voltage crept up to 0.9v and higher as it discharged. So something definitely was holding back the voltage potential that got better as power was pulled out of the cell.



You're wasting your time discharging under performing cells at high discharge rates. High discharge rates only draw from the smaller particles in the cell. It takes a slow discharge to break up the larger crystalline formations. Until you free up the compounds in the cell, I doubt any amount of forming will have much effect.

Dave


----------



## TorchBoy

Depends what you mean by OK, I suppose. Were you charging at 200 mA, not 250 mA?

Dave, does the voltage recover because it starts drawing from the large crystals?


----------



## Bones

bcwang said:


> ...
> But this is one flaw I see on the c9000 that I hope gets addressed in future models. Pulse discharge with high amperage won't take enough energy out of the cell to condition them unless the termination voltage is revised. In my case, all 4 of these cells run great on the L1D on High for a long time, so they are very usable. If I just trusted the c9000 0mah capacity, I would have thrown them out. Now I have to re-evaluate a lot of cells I put in the "junk" heap since they actually might be ok still.



It it the MH-C9000's pulsed discharge at high amperage versus a continuous discharge at low amperage that's at issue here?

In other words, is it that a pulsed discharge at high-amperage to 0.9 volts draws out less energy than a continuous discharge at low-amperage to 0.9 volts?

Or, is the issue with the charger discontinuing the discharge at 0.9 volts instead of some lower voltage?


----------



## bcwang

Mr Happy said:


> You didn't need to run 16 [email protected] mA, you could have taken it more gently as I suggested above.



Um, break-in mode on the c9000 of a 2500mah cell is 16 [email protected] am I wrong? That was your gentle suggestion! 

Bones, 

I'm not sure what difference a pulsed discharge vs continuous discharge makes for helping condition a cell. The issue I mentioned is the fact that it terminates discharge when it hits 0.9v. which under a high pulse load means there is substantial energy in the cell left if that cell drops a lot of voltage under higher loads. 

I can take that same cell that was instantly terminating discharge on the C9000 with it's 100mah discharge setting (1am pulsed at 10% duty), and get over 2000mah out of it with a true 100mah constant discharge to 0.9v on the CBA II, this is right after taking it out of the c9000 discharge mode with it reporting 0mah capacity.


----------



## 45/70

TorchBoy said:


> Dave, does the voltage recover because it starts drawing from the large crystals?



The short answer is, yes. A cell with large crystalline formations will recover to a higher voltage than a cell in good shape, after being discharged at a high rate. The reason being that under heavy discharge, only the smaller particles (crystals) are able to sustain the load. The large crystals can't release energy as fast so their basicaly not involved (this is also one of the causes of "voltage depression"). At a slow enough discharge rate, the larger crystals don't have any problem supplying energy, and all seems well.

Here's an analogy. Compare 70 grains of Fg black powder to 70 grains of FFFFg black powder. They both have the same amount of energy, but the FFFFg being smaller granules, burns faster, and thus releases it's energy faster than the Fg. The Fg with it's significantly larger granule size burns slower and therefore releases it's energy slower, over a longer period of time. Pretty much the same thing is going on in the cells. Eh, maybe not such a great analogy, but hope you get the idea.

Back to NiMH cells, if you have "crap cells" there's really only one of two reasons that they're "crap". One is the separator is deteriorated. There's not really anything that can be done here. The other is the large crystal formation problem. The idea here is to break up the formations into smaller parts and *then* do a forming charge to mix the chemicals back into the mix. It's also important to mention here, that if you have a cell that has large crystal formations within it, and you charge the cell at a high rate, the crystals can cut into the separator and damage it during the process. At this point you have an irreparable "crap cell"

I'm no expert on this phenomenon, but when I first got my CBA II, I did a lot of research and playing around with "crap cells" Ask Tom, I'm pretty sure he thought I was nuts! It was interesting, because at low discharge rates, particularly near the end of discharge, you can actually see the formation breaking up. The voltage will drop slowly down and then suddenly shoot up. "Hey I busted up a crystal". Ahem, anyway I felt like I learned something of value from "crap cells".

OK, back on topic! 

Dave


----------



## digitor

bcwang said:


> I'm not sure what difference a pulsed discharge vs continuous discharge makes for helping condition a cell. The issue I mentioned is the fact that it terminates discharge when it hits 0.9v. which under a high pulse load means there is substantial energy in the cell left if that cell drops a lot of voltage under higher loads.
> 
> I can take that same cell that was instantly terminating discharge on the C9000 with it's 100mah discharge setting (1am pulsed at 10% duty), and get over 2000mah out of it with a true 100mah constant discharge to 0.9v on the CBA II, this is right after taking it out of the c9000 discharge mode with it reporting 0mah capacity.


The early version of the C9000 measures the off-load voltage, which avoids this situation. Trouble is, discharges can take a loooong time with a crap cell - I guess you can't have the best of both worlds! (Well, maybe you could if this behaviour was selectable somehow, with a firmware revision....)

Cheers


----------



## Bones

bcwang said:


> ...
> I'm not sure what difference a pulsed discharge vs continuous discharge makes for helping condition a cell. The issue I mentioned is the fact that it terminates discharge when it hits 0.9v. which under a high pulse load means there is substantial energy in the cell left if that cell drops a lot of voltage under higher loads.
> 
> I can take that same cell that was instantly terminating discharge on the C9000 with it's 100mah discharge setting (1am pulsed at 10% duty), and get over 2000mah out of it with a true 100mah constant discharge to 0.9v on the CBA II, this is right after taking it out of the c9000 discharge mode with it reporting 0mah capacity.
> 
> 
> 
> digitor said:
> 
> 
> 
> The early version of the C9000 measures the off-load voltage, which avoids this situation. Trouble is, discharges can take a loooong time with a crap cell - I guess you can't have the best of both worlds! (Well, maybe you could if this behaviour was selectable somehow, with a firmware revision....)
> 
> Cheers
Click to expand...


Thanks, got it.

Incidentally, I have an original edition MH-C9000, and have observed the extended discharge times on certain cells.

Is it safe to conclude that those cells that take considerably longer than their brethren to discharge to 1.0 volts are not as healthy, and either closer to their recycle point or in need of more conditioning?

This is predicated on the cells being identical in all other respects of course.


----------



## digitor

Bones said:


> Thanks, got it.
> 
> Incidentally, I have an original edition MH-C9000, and have observed the extended discharge times on certain cells.
> 
> Is it safe to conclude that those cells that take considerably longer than their brethren to discharge to 1.0 volts are not as healthy, and either closer to their recycle point or in need of more conditioning?
> 
> This is predicated on the cells being identical in all other respects of course.


In my experience, yes. I use this behaviour as a good indicator of when to get rid of a cell - they are of no use to me if they won't hold at least a 1 amp discharge. (This hasn't happened with an Eneloop yet, they're all I use now).

Cheers


----------



## TakeTheActive

RE: 'CRAP CELLS' and attempting to use them as long as possible, I'm with you... :thumbsup:


45/70 said:


> ...*I use crap cells in wall clocks, LCD thermometers, and such with great success. They run devices anywhere from 3-6 months between charges and have done so for years after turning into "crap cells". I'll be damned if I'm going to put a brand new eneloop in them!* :nana:



And, the fact that the BC-900 can further DISCHARGE cells that the MH-C9000 can't, YEP! :thumbsup:


45/70 said:


> ...When cells are this bad (ie. they won't discharge in the C-9000), *it is absolutely mandatory* _*to do a*_ _*slow discharge*_ before attempting the break in. You need to break up any crystallization in the cells, which I'm sure are present in this situation. The CBA is a great way to do this as well as discharge the cell, but as bc pointed out, it's takes forever. The BC-900 is a good alternative (sorry Maha). What I have done, is discharge the cells at 100mA in a BC-900. Pull the cells when the discharge stops...



But, I don't understand this :thinking:


45/70 said:


> ...*When you're totally sick of this phase, or your patience runs out, whichever comes first , charge them on whatever charger will work, at 1C for about 5 minutes, let them rest a few minutes, then go back and do the discharge routine again. It doesn't hurt to repeat all this 2-3 times*...


What does '*5 minutes @ 1C... ...2-3 times*' accomplish that a *R&A* Full Charge wouldn't?  I.E., how does this 'cycle' any more chemicals?



45/70 said:


> ...When cells are this bad (ie. they won't discharge in the C-9000), *it is absolutely mandatory* _*to do a*_ _*slow discharge*_ before attempting the break in. You need to break up any crystallization in the cells, which I'm sure are present in this situation...


For *REALLY* CRAP cells, YEP once again. :thumbsup: After a DISCHARGE with the MH-C9000 @ 100mA and then the BC-900 @ 100mA, for the *REALLY* CRAP cells, I use a 'Superman 1AA Flashlight *FREE* from Duracell' to further discharge the cell (I point the flashlight at where I'm sitting and end the discharge when the lamp 'suddenly' dims. At this point-in-time, all of the CRAP cells I've experimented with will recover to over 0.9VDC UNLOADED).



45/70 said:


> ...This is the only way I've found to do a proper break in on "crap cells". The theory is, if there are large crystalline formations in the cell when trying to form it ("break in"), the chemicals won't properly redistribute throughout the cell...


We pretty much agree here - 'Break up the large crystals first!' :twothumbs


----------



## TakeTheActive

45/70 said:


> The short answer is, yes. A cell with large crystalline formations will recover to a higher voltage than a cell in good shape, after being discharged at a high rate. The reason being that under heavy discharge, only the smaller particles (crystals) are able to sustain the load. The large crystals can't release energy as fast so their basicaly not involved (this is also one of the causes of "voltage depression"). At a slow enough discharge rate, the larger crystals don't have any problem supplying energy, and all seems well...


Agree! I've seen some of my *REALLY* CRAP cells POP higher in voltage during discharge (on my BC-900) and, from what I've read on the CPF Archives, it's due to the LARGE crystals breaking up.



45/70 said:


> ...Back to NiMH cells, if you have "crap cells" there's really only one of two reasons that they're "crap". One is the separator is deteriorated. There's not really anything that can be done here. The other is the large crystal formation problem. The idea here is to break up the formations into smaller parts and *then* do a forming charge to mix the chemicals back into the mix. *It's also important to mention here, that if you have a cell that has large crystal formations within it, and you charge the cell at a high rate, the crystals can cut into the separator and damage it during the process. At this point you have an irreparable "crap cell"*...


Huh?  How??

From my readings of the CPF Archives (*SilverFox*), HIGH charge currents produce SMALL crystals and LOW charge currents produce LARGE crystals. So, how can a LARGE charge current cause existing LARGE crystals to puncture the separator more than a SMALL charge current?


----------



## TakeTheActive

Bones said:


> ...Incidentally, I have an original edition MH-C9000, and have observed the extended discharge times on certain cells.
> 
> Is it safe to conclude that those cells that take considerably longer than their brethren to discharge to 1.0 volts are not as healthy, and either closer to their recycle point or in need of more conditioning?
> 
> This is predicated on the cells being identical in all other respects of course.


Please explain further - i.e. I don't understand your point. 

Logically, how can a cell discharging @ XXXmA to 1.0VDC display THE SAME mAh capacity @ YY or YY+ZZ minutes? mA times hours equals mAh - right?

For "..._those cells that take considerably longer than their brethren to discharge to 1.0 volts_...", what is their mAh? 

IMO bottom line, Capacity equals Capacity. I note what mA a 'calculated' Capacity is for and use my cells accordingly. (i.e. LOW Internal Resistance cells can supply a higher mA *PER hour* than HIGH Internal Resistance cells.)


----------



## Mr Happy

TakeTheActive said:


> Please explain further - i.e. I don't understand your point.


When the C9000 (the first version) finds that a cell cannot sustain the requested discharge current without the voltage dropping too much it decreases the discharge current to a lower value and prolongs the discharge to help it complete fully.


----------



## TorchBoy

I'm a little confused over this current size/crystal size thing too. Does lots of slow charging cause big crystals? I'm sure SilverFox said fast charging keeps cells vibrant. Or is it important to charge at about the same rate they'll be discharged at?

I tested a friend's Eneloops last night. He slow charges, but uses them in a digital camera (fast discharge if using flash?). They don't seem to hold a very good voltage, and before we left the cells to have dinner I noticed at least one had recovered 0.05 V (from 1.09 to 1.14 V). How much recovery indicates a significant large-crystal problem?


----------



## TorchBoy

TakeTheActive said:


> (i.e. LOW Internal Resistance cells can supply a higher mAh than HIGH Internal Resistance cells.)


So Eneloop with its low internal resistance should have a higher capacity than high capacity cells with slightly higher internal resistance? Are you saying there's a direct correlation?



Mr Happy said:


> When the C9000 (the first version) finds that a cell cannot sustain the requested discharge current without the voltage dropping too much it decreases the discharge current to a lower value and prolongs the discharge to help it complete fully.


Is that deliberate, and a pulsed discharge current, or is it an underfed continuous current that would be a high pulsed current if it was able to? I suspect the latter.


----------



## digitor

Mr Happy said:


> When the C9000 (the first version) finds that a cell cannot sustain the requested discharge current without the voltage dropping too much it decreases the discharge current to a lower value and prolongs the discharge to help it complete fully.


Wel, not really - it seems that it is an unintended consequence. What is actually happening is that during discharge, the early version measures the voltage off-load, so the voltage of a high impedance cell is able to bounce back to a value of 1V or greater, therefore the 9000 keeps trying to discharge. As soon as the discharge recommences, the voltage sags so the discharge rate cannot be sustained at the programmed rate, therefore it takes longer.

Cheers


----------



## TakeTheActive

TorchBoy said:


> I'm a little confused over this current size/crystal size thing too. Does lots of slow charging cause big crystals?


There are several interesting / informative LINKs in my Sig Line LINKs discussing:
Crystals
Charging Rates
Storage Box Queens
Read through them and then come back with YOUR comments / observations. :thinking:


----------



## TakeTheActive

TorchBoy said:


> TakeTheActive said:
> 
> 
> 
> ...(i.e. LOW Internal Resistance cells can supply a higher mA *PER hour* than HIGH Internal Resistance cells.)
> 
> 
> 
> So Eneloop with its low internal resistance should have a higher capacity than high capacity cells with slightly higher internal resistance?
Click to expand...

No. And I just edited my earlier post to make it clearer.

I'm saying that NEWER cells with LOW Internal Resistance can supply mA at a higher rate *PER hour* than OLDER cells with HIGH Internal Resistance (i.e. our 'non-vibrant' *CRAP* cells).

You may be able to Discharge a *CRAP* cell @ 100mA (and lower) and get 80% of it's original Capacity but raising the rate to 1000mA (and higher) may drop the available Capacity to 60%.


----------



## TakeTheActive

digitor said:


> ...What is actually happening is that *during discharge, the early version measures the voltage off-load*, so the voltage of a high impedance cell is able to bounce back to a value of 1V or greater, therefore the 9000 keeps trying to discharge. As soon as the discharge recommences, the voltage sags so the discharge rate cannot be sustained at the programmed rate, therefore it takes longer.


Sounds like the current La Crosse BC700/BC900/BC9009 design... :thinking:

Combine that with the lack of a REST period between Charge and Discharge and you get the 'artifically' higher Capacity readings from the La Crosse chargers compared to the new-style / current Maha MH-C9000.

*Question(s) to owners of BOTH old-style and new-style MH-C9000s (and possibly one of the La Crosse models): *
Do you see consistently higher Capacity readings from your old-style C9000 compared to your new-style?
.
If you also have a La Crosse, how close are the old-style C9000 Capacity readings to the La Crosse?
Thanks!


----------



## Mr Happy

TakeTheActive said:


> I'm saying that NEWER cells with LOW Internal Resistance can supply mA at a higher rate *PER hour* than OLDER cells with HIGH Internal Resistance


Unfortunately I think you just made things less clear. The phrase "supply mA at a higher rate per hour" really has no meaning. There is no such thing as mA per hour.

It works like this: a rate of 1000 mAh per hour (1 coulomb per second) is equal to a current of 1000 mA. So batteries with a lower internal resistance can supply mAh (charge) at a higher rate than batteries with a higher internal resistance for the same voltage drop. Which simply translates to saying batteries with a lower internal resistance can supply higher currents than batteries with higher internal resistance.

In reality, batteries with a higher internal resistance do appear to have a lower capacity when discharged at a higher rate, which is what I think you are getting at. The lower capacity is because the battery reaches the end point voltage more quickly where it is not able to continue discharging energy in a useful way. So you get less useful energy out of the battery at the higher discharge rate.


----------



## TorchBoy

TTA, if you're talking about a rate it would be "something per time" anyway. And capacity per hour is current...


Mr Happy said:


> ... Which simply translates to saying batteries with a lower internal resistance can supply higher currents than batteries with higher internal resistance.


----------



## 45/70

TakeTheActive said:


> What does '*5 minutes @ 1C... ...2-3 times*' accomplish that a *R&A* Full Charge wouldn't?  I.E., how does this 'cycle' any more chemicals?



It is much faster. It doesn't accomplish any more than is needed. The large crystals still have their charge. You only need to charge up the smaller particles a bit, to prevent undervolting the cell when discharging.



TakeTheActive said:


> Huh?  How??
> 
> 
> 
> Originally Posted by *45/70
> * *It's also important to mention here, that if you have a cell that has large crystal formations within it, and you charge the cell at a high rate, the crystals can cut into the separator and damage it during the process. At this point you have an irreparable "crap cell"*...
Click to expand...


As I remember, it has to do with the heat generated within the cell (not necessarily felt on the outside surface). As the compounds in the cell start churning around at high charge rates, the separator can be punctured or torn.



TakeTheActive said:


> From my readings of the CPF Archives (*SilverFox*), HIGH charge currents produce SMALL crystals and LOW charge currents produce LARGE crystals. So, how can a LARGE charge current cause existing LARGE crystals to puncture the separator more than a SMALL charge current?



This is true. See comment above.

I want to add that while the BC-900 does have a few advantages in some areas, my AA/AAA charger arsenal consists of three C-9000's and one BC-900.


----------



## 45/70

TorchBoy said:


> I'm a little confused over this current size/crystal size thing too. Does lots of slow charging cause big crystals? I'm sure SilverFox said fast charging keeps cells vibrant. Or is it important to charge at about the same rate they'll be discharged at?
> 
> I tested a friend's Eneloops last night. He slow charges, but uses them in a digital camera (fast discharge if using flash?). They don't seem to hold a very good voltage, and before we left the cells to have dinner I noticed at least one had recovered 0.05 V (from 1.09 to 1.14 V). How much recovery indicates a significant large-crystal problem?



As I understand it, yes, large crystalline formations are caused by slow charging. The question is, how slow? My research on this has always been somewhat inconclusive. It would seem most agree that a "standard charge" of 0.1C does not promote large crystalline formation (nor does it alleviate the problem). I've even come to the conclusion that 0.05C is OK. Lower than that, seems to be where they form.

I also think that "self discharge" promotes large crystal formation as, in my experience, these cells seem to show the most prominent signs. It could be though, that a damaged separator is playing a bigger part here. Not sure.

Dave


----------



## Bobor

I found some old "Bossman" and "DynaCharge" AA's purchased in the early 90's in a drawer and the MAHA seems to be able to charge them (i.e. no HIGH displayed) but the batteries themselves have no indication of their capacity written anywhere on them

What Discharge/Charge rate should I use when using the Break In or any of the other modes if I don't know their capacity?


----------



## TakeTheActive

Bobor said:


> I found some old "Bossman" and "DynaCharge" AA's purchased in the early 90's in a drawer and the MAHA seems to be able to charge them (i.e. no HIGH displayed) but the batteries themselves have no indication of their capacity written anywhere on them
> 
> *What Discharge/Charge rate should I use when using the Break In or any of the other modes if I don't know their capacity?*



I'd start out with a BREAK-IN @ 1500mA
Then, I'd take the average Capacity reported rounded up to the next 100 and call that 'C'.
Depending on the amount of built-up Internal Resistance, I'd then CHARGE @ 0.5-0.67C and DISCHARGE @ 0.2C a few times and see what results I'd get.
Good Luck!


----------



## tr098a

My current cheap-o charger is started to act up so I've been looking at a c9000 and have a few questions.
Is it possible to select a 2A charging rate for all 4 cells? Or only for 1or2 cells?
Is there any way to tell the firmware without opening the box?
Has anyone found that companies have old stock? Has anyone who recently bought one had old firmware?


----------



## Codeman

The C9000 allows individual settings on each of the 4 stations. You could charge at 1A in one, 2A in another, a 0.5A discharge in the third, and be doing a refresh in the fourth slot, all at the same time.

I don't think firmware versions are on the outside, but unless things have changed, they come in a cardboard box with a flap top, so you can return it in pristine condition if you want. Thomas Distributing is good to deal with, and they probably have a good turnover of their stock.


----------



## Bones

tr098a said:


> My current cheap-o charger is started to act up so I've been looking at a c9000 and have a few questions.
> Is it possible to select a 2A charging rate for all 4 cells? Or only for 1or2 cells?
> Is there any way to tell the firmware without opening the box?
> Has anyone found that companies have old stock? Has anyone who recently bought one had old firmware?



As Codeman has indicated, whatever it will do with one cell, the MH-C9000 it will do with 2, 3 and/or 4. Just consider it four 1 bay chargers with respect to applying its full range of settings to individual cells.

There were only three modifications noted, and the last was some time ago. The first altered it's charge termination process. The second rectified what was known as the repeating digit error; which was essentially an error reporting the results of one bay on the second cyle when in the cycle mode. The third ramped up the already bright backlight of the display.

Perhaps someone else can confirm this, but insofar as I can recall, if you receive one with the code on the label beginning after 0G (zero G), ie: 0H, you should be okay.


----------



## Bobor

I've been doing some research on the net and the information out there has got me a little confused about maintaining those bateries that are in in 'long term' storage.

So to clarify:

For batteries that aren't used (or aren't going to be used) in a long time, say over a year, we should take these out and run them though the Refresh/Analyze mode on the c9000 every 6 months. Correct?

Do we then store these with the full charge that results? There are references that they should be stored with a partial charge (how to easily acheive this on the Maha?)

Does the above process apply to both Nimh and Nicds?


----------



## Anders

Hello Bobor.

Read this post by Silverfox.
"Storing cells is a balancing act. The best way to store cells is to have them in a discharged condition and stored at around 40 F. At cooler temperatures, the chemical activity within the cell is greatly reduced, but does not completely stop. You can’t just leave them, or they will continue to run completely down resulting in an over discharged state that damages the cell. When you store cells in a discharged state, you need to do a charge/discharge cycle every 30 days to keep the chemistry active. If you want to store for longer periods of time, you can discharge the cells, then put a partial charge back on them."



A partial charge can be done by first discharging and then charging 20-25% or so, then removed.

Anders


----------



## TakeTheActive

Bobor said:


> I've been doing some research on the net and the information out there has got me a little confused about maintaining those bateries that are in in 'long term' storage.
> 
> So to clarify:
> 
> *For batteries that aren't used (or aren't going to be used) in a long time, say over a year, we should*...


Click on my Sig Line LINK and read about '*Storage Box Queens*'.


----------



## Burgess

to TakeTheActive --


:wow:


That is a *wonderful* information resource you've compiled !


Thank you for your time, effort, and dedication.


:goodjob::thanks:

_


----------



## FUNWITHPOWER

Ok I Have a couple of questions which you guys will probably answer with no problem, and for my first one, I have the MH-C9000 and Brand New eneloop batts and it seems it is best to discharge them first then break-in, but I wanted to know if just putting them in the device that they were bought for to do the discharging and (whatever that may be, RC transmitter most likely in my case) then do the break-in on the MH-C9000, or is it best to do the discharge with the MH-C9000??? (Better for the longevity and performance of the batts) My next question is, in discharge mode does it automatically start a top off charge and trickle charge after discharge in discharge mode has finished, because that is what my manual seems to say, but it seems I have read in other places that it does not charge... last question is once the MH-C900 is "DONE" mode, can all variables be viewed (capacity, voltage, time, and current,), or just the capacity, because again the manual makes it sound capacity is all that can be viewed once the program is finished??
Thanks a lot guys!!!


----------



## pobox1475

> RC transmitter most likely in my case) then do the break-in on the MH-C9000, or is it best to do the discharge with the MH-C9000?


 I would use C9000. Transmitter will take a lot longer. 



> next question is, in discharge mode does it automatically start a top off charge and trickle charge after discharge in discharge mode has finished


 In my experience, no.



> last question is once the MH-C900 is "DONE" mode, can all variables be viewed (capacity, voltage, time, and current,), or just the capacity, because again the manual makes it sound capacity is all that can be viewed once the program is finished?


 I will leave this for an expert to answer. I usually just pull e'm off assuming charger has don it's best. I would like to know what info is worth noting to be aware of the cells condition.


----------



## pobox1475

Oh, yea FUNWITHPOWER :welcome:.......................................


----------



## PEU

I purchased a C9000 at Thomas Distributing on 4/30/2007 it worked great for a while but around mid 2008 the rightmost slot began to malfunction causing the charger to self reset. 
Since then I solved it by putting a duracell (non rechargeable) battery in it so it detects is high impedance and does not use that slot. The other 3 work OK.

If I were in USA I would send the unit back for a replacement, but since Im in Argentina, TD told me (on febb/2009) that they do not pay for shipping overseas for warranty replacements.

I would like to know if someone knows how to fix this.
or should I contact Maha directly to check if they assume the back/forth shipping?

Ideas?

Thanks


Pablo


----------



## pobox1475

> should I contact Maha directly to check if they assume the back/forth shipping?


 I would. If they determine that it was defective they should help you.


----------



## jonnyfgroove

*Questions about new C9000*

I recently received a new C9000 from a reputable online dealer. The model number is 0G0C01. Is this an old model with the bugs or am I good to go? I've searched and read about it, but I'm still unclear.:duh2: Also, I noticed the charger takes a two hour rest after the first charge in R&A when I was expecting one hour. Thanks.


----------



## TorchBoy

PEU said:


> If I were in USA I would send the unit back for a replacement, but since Im in Argentina, TD told me (on febb/2009) that they do not pay for shipping overseas for warranty replacements.
> 
> I would like to know if someone knows how to fix this.
> or should I contact Maha directly to check if they assume the back/forth shipping?


Hi Pablo. Yes, contact Maha. I went to Maha directly when I had a MH-C9000 that did the same thing. They were great to deal with, and sent a new unit straight to me.


----------



## PEU

Sent and email to Maha and I got a reply from Eric, he told me that a new unit will be shipped to my home address here in Buenos Aires. Now the wait begins.

will keep you guys posted.

*[edit] *minutes after I posted this I received this notification from USPS: This ship notification is being sent to you by the U.S. Postal Service at the request of MAHA ENERGY CORP. 
Woohoo!! they are sending me one via priority Mail Intl.

Pablo


----------



## 45/70

Hummm. My first C-9000's (0G0IA) display has gone wonky. It seems to still work, but it's _really_ difficult to read. Guess I need to shoot them an email, huh.

Dave


----------



## FUNWITHPOWER

Does anyone else have any answers to my questions on my post 477, Thank you very much POBOX for your answers; I am still waiting for an "expert" to answer the last question and also their input on the other two. 45/70, Mr. Happy, you guys have any answers???? You guys seem to be some of the "Big Dogs" around these Parts"  Any Help or advice is very welcome!! Thanks!


----------



## Bones

*Re: Questions about new C9000*



jonnyfgroove said:


> I recently received a new C9000 from a reputable online dealer. The model number is 0G0C01. Is this an old model with the bugs or am I good to go? I've searched and read about it, but I'm still unclear.:duh2: Also, I noticed the charger takes a two hour rest after the first charge in R&A when I was expecting one hour. Thanks.



It's almost certain you've received a model with the first and most important revision.

However, it may or may not have a second, less critical revision, which rectified a repeating digits bug in its display.

To determine whether it has the second revision, run the cycle mode on a cell in slot one for at least two cycles.

If the digits for the results of the first cycle repeat, ie: 1515 instead of 1527 for example, repeat the test again. If the digits repeat again, your charger probably doesn't have the second revision.


----------



## TorchBoy

FUNWITHPOWER said:


> *1. *... Brand New eneloop batts ... I wanted to know if just putting them in the device that they were bought for to do the discharging ... or is it best to do the discharge with the MH-C9000?
> 
> *2.* My next question is, in discharge mode does it automatically start a top off charge and trickle charge after discharge in discharge mode has finished ...
> 
> *3.* last question is once the MH-C900 is "DONE" mode, can all variables be viewed (capacity, voltage, time, and current,), or just the capacity...?



1. I'll vote for the MH-C9000. End of discharge will likely be at a more precise point, but it probably won't make any practical difference other than (as pobox said) the time it'll take.

2. The Discharge mode just discharges then sits there; no charging afterward. Other modes that cycle the battery start charging them after an hour pause.

3. It will display the capacity, time taken, present voltage. If you've been using Cycle mode then you can get the previous cycle capacities by pressing the up and down arrows.


----------



## 45/70

FUNWITHPOWER said:


> Does anyone else have any answers to my questions on my post 477......



Sorry FUN, I missed your post earlier. Fortunately, TorchBoy stepped in to answer your questions. Nice job Torch! :thumbsup:

As far as



FUNWITHPOWER said:


> I am still waiting for an "expert"..........45/70, Mr. Happy............You guys seem to be some of the "Big Dogs" around these Parts



I'm not an expert, although at 6'3", 235lbs, big dog with a loud bark, maybe.

While I have been using individual rechargeable cylindrical cells for 25+ years, and thus have some experience, a good part of what I've learned about them has been since I joined CPF. Some of the folks (and yes Mr H is one of them, among many others, don't forget SilverFox!) on this forum are a wealth of knowledge. Add to that various links to information that people provide, and it's not hard for anybody to obtain an understanding of rechargeable battery cells and how to feed and care for them.

Dave


----------



## pobox1475

> Woohoo!! they are sending me one via priority Mail Intl.


 Now *that's *what I'm talkin bout. I love good *CS...
*


----------



## jonnyfgroove

*Re: Questions about new C9000*



Bones said:


> It's almost certain you've received a model with the first and most important revision.
> 
> However, it may or may not have a second, less critical revision, which rectified a repeating digits bug in its display.
> 
> To determine whether it has the second revision, run the cycle mode on a cell in slot one for at least two cycles.
> 
> If the digits for the results of the first cycle repeat, ie: 1515 instead of 1527 for example, repeat the test again. If the digits repeat again, your charger probably doesn't have the second revision.


 
Thanks Bones! I haven't tried cycle mode yet. These things are just too cool.


----------



## FUNWITHPOWER

Thanks guys!! The Batts are now discharging, but another question, does the MH-C900 have the ability to actually see how much MAH (capacity) is come out of the battery?? I ask this because if you do the math, say I am doing a discharge at 100MAH and it has been 3hours then the MAH value should be 300MAH, right??? So I did this same thing while I was watching the MH-C9000 discharging and it is off, so I am guessing the MH-C9000 is more accurate as it can read the actual MAH that’s is coming out..?? Just making sure… 

So what should be a good set of discharge results (higher the better?)?? Because at the end it should pretty much tell me the capacity of my eneloops right??? 

Thanks again…. This is a great site!!! 

Oh also is there a specific time I should wait to do the break-in after completion of the discharge (probable getting to specific now..., but then again I think this is what you guys are all about right)??? DETAILS DETAILS DETAILS.....


----------



## TorchBoy

If you want more details, then discharging at 100 mA for 3 hours is 300 mAh; mA x h = mAh. Note the capitalisation of the units.

Yes, the MH-C9000 knows how many mAh it's actually drawing out of the cells, and will be "off" by a little as it has a 90% duty cycle, so if you discharged at a nominal 100 mA for 10 hours you'd get around 900 mAh at the end of it, not 1,000 mAh (1 Ah).


----------



## Bobor

Hope this isn't too dum a question: I have a couple of 300mah AAA Nicds that I'd like to put through a Break-in mode on the Maha but the lowest battery capacity is 500mah. Below that and I get 20.00Ah. 

Should I use 20.00ah as the battery capacity for these in the Break-In mode?


----------



## Mr Happy

Bobor said:


> Hope this isn't too dum a question: I have a couple of 300mah AAA Nicds that I'd like to put through a Break-in mode on the Maha but the lowest battery capacity is 500mah. Below that and I get 20.00Ah.
> 
> Should I use 20.00ah as the battery capacity for these in the Break-In mode?


Heavens, no! 

20 Ah is 20,000 mAh. You will explode the cells.

I don't think you can run a break-in on 300 mAh cells with the C9000. The capacity is unfortunately too low.


----------



## Bobor

Mr Happy said:


> I don't think you can run a break-in on 300 mAh cells with the C9000. The capacity is unfortunately too low.



Is this to say then that I can't really do anything in terms of maintenance on these cells with the c9000?

I sometimes keep these in storage for months at a time (I use a single one at a time for an old MP3 player); will "conditioning" them at charge rate say of 200mah and discharge of 100mah do any good?


----------



## SilverFox

Hello Bobor,

If they were my cells I would charge them at 300 mA and discharge them at 100 mA.

I would store the cells in a discharged condition, and do the charge/discharge cycle once a month.

Tom


----------



## PEU

pobox1475 said:


> Now *that's *what I'm talkin bout. I love good *CS...
> *



And it arrived! They followed my request to declare the item as: Warranty replacement of no commercial value and I ended paying ZERO at customs!

Great service, kudos to Maha!


Pablo


----------



## Bobor

SilverFox said:


> Hello Bobor,
> 
> If they were my cells I would charge them at 300 mA and discharge them at 100 mA.
> 
> I would store the cells in a discharged condition, and do the charge/discharge cycle once a month.
> 
> Tom



Thanks Siverfox. Out of curiosity, what's the concept behind charging them at 1c as you suggested? Is the idea here to prevent crystal formation, redistribute electolytes etc?


----------



## SilverFox

Hello Bobor,

NiCd chemistry seems to work very well when charged in the 1 - 2C range. Since your cells are old, I picked a lower charge rate, in that range.

Crystals are broken up during discharging, and electrolyte re-distribution is best done by charging at 0.1C. Since the C9000 doesn't offer the low charging rates you need, I simply suggested values I have successfully used in the past.

Tom


----------



## PEU

PEU said:


> And it arrived! They followed my request to declare the item as: Warranty replacement of no commercial value and I ended paying ZERO at customs!
> 
> Great service, kudos to Maha!
> 
> 
> Pablo



And Im going to receive a new one...

The replacement I received didn't work correctly, it left batteries with around 380ma (eneloops AA) compared it with the original one that had the rightmost bay damaged the batteries charged to 2000ish ma

Maha support asked me to do a couple of tests, send them photos of the results (I sent videos) and they determined there was indeed a problem with the charger.

Now Im curious, when I receive the new unit I will check/compare the multitude of test points the pcb board has. 
If anyone went this route and have some insight, I would like to know.


Pablo


----------



## TorchBoy

PEU said:


> If anyone went this route and have some insight, I would like to know.


Not quite what you mean, but I've been the route of having several go faulty (which I don't at all think is typical). Maha's customer service has been great, though.

I don't know anything about test points but it sounds interesting.


----------



## PEU

Received the new one, asked them to send 4 batteries to test the new charger and they did that too (4x powerex 2700) 
Now Im doing a break in cycle to all of them, hopefully when I return to the office on monday they are charged correctly.


Pablo


----------



## TorchBoy

PEU said:


> asked them to send 4 batteries to test the new charger and they did that too (4x powerex 2700)


Did you pay for those or did they?


----------



## PEU

TorchBoy said:


> Did you pay for those or did they?



No, they send them for free after I asked to send the batteries they used to pretest the charger before sending it, but the battery package was closed, so I guess they just tossed a similar package of the batteries they used, I really appreciate that. 
I really hope this new charger works as expected. Will post the result tomorrow when I return to the office


Pablo


----------



## TorchBoy

That's very nice of them. I note that it's almost 2 years and 11 months since I bought mine. My last MH-C9000 has been going quite well, so I hope I won't need the 3 year warranty again.


----------



## PEU

The batteries charged to almost all their capacity (real 2540 vs 2700ma branded) but we all know there is always a 10% "error" in the marketing packages... 

Well, I also hope I don't need the warranty again, Im really gratefull for the excelent maha customer service.


Pablo


----------



## tundraotto

Its the customer service posts like yours, along with the opinions & info from the battery gurus (you all know who you are). It made my choice easy and boy am I a happy camper!! doing 3 refresh/anyze cycles and 1 break-in...and I am wondering who do people complain about this user interface??!?!? I mean come on - maybe MAHA can make one with a keyboard and charge $200 for that and pass the savings to us penny pinchers who realize the good price point this product is offered!!!

Awesome - I am happier with this than with my Ultrafire A10 that kicks butt @$17 - I mean really a TK11 R2 next to this noes not put the a10 to shame in the least - its pretty ghastly owning both of them and knowing what the price/size difference is....I am just glad I have both!!!!

See - even a blind squirrel finds a nut every now and then:thumbsup:


----------



## jozek

I've recenty bought MH-C9000 charger, as my brother have the same for some time and was very happy with it. I was using it for charging AA cells and all was working fine. Problems started when i try to charge AAA cells. With those batteries there is a contact problem on positive electrode. AAA batteries are very loose, and it often stop charging sometimes. Also smetimes there are small "sparks" and buzzing becouse of that.
I went to see my brothers charger and it turned out the shape of electrodes on his charger are different wich makes AAA batteris "click" in correct place nicely (see pictures). On mine with some force i can push batteries so they would click in those two small bottom "peaks" but then it badly scratches electrodes on the cell.
Does any1 have any problem as me, is this new type of charger or smth?
Mine is "0101A" my brothers "0H0DA".

My brother electrodes:
http://img237.imageshack.us/i/old2.jpg/ (fixed)

Mine:
http://img46.imageshack.us/i/new2a.jpg/

Scratches on batteries:
http://img269.imageshack.us/i/98957996.jpg/
http://img203.imageshack.us/i/31988544.jpg/


----------



## Turbo DV8

Pictures of your brother's electrodes aren't coming through. I had a similar contact problem with AAA cells on my two C9000's, but it was the negative end. I returned both chargers.


----------



## Mr Happy

:welcome:

The C9000 can have a problem with AAA cells, but it is usually found to be at the negative end rather than the positive end. When you insert the batteries, do you push the negative end down firmly first, and then while holding it down click the positive end down into position? That is the only way I can securely insert AAA cells into my C9000.

Also, I have to make sure the wrapper does not wrap around the negative end of the cell. If it does I have to trim it off with scissors to expose plenty of metal. Otherwise the plastic gets in the way of the spring and prevents good contact.


----------



## jozek

Fixed link on previous post.
Contact on negative end is fine with batteries, end yes i place negative end first then push batteries down. The thing is that if i turn charger upside down and shake a bit then batteries will fall of from charger, there is not eneough pressure to keep them. As i mention i could push them them further down, so they would catch on those two bumps, but it scratches batteries badly.

As for minus electrodes there some differences on them aswell. 
The old ones pics: http://img251.imageshack.us/i/oldminus.jpg/
and those r mine : http://img192.imageshack.us/i/newminus.jpg/ 
IMO the new ones have better connection there.

When i plug batteries on mine it seems like the plus electrode in charger is too deep, and battery case stops on plastic cover of charger. Its worst on 1 and last sockests, and the issue is smaller on the middle ones.
http://img163.imageshack.us/i/newbattery.jpg/

On the old chargers everything works great, and connection sie nice.
http://img230.imageshack.us/i/oldbattery.jpg/

If i push batteries very hard (alot of force needed) then connection is nice, but it scratches battery and its difficult to remove them after (again a lot of force is needed). 
http://img163.imageshack.us/i/newpushed.jpg/

Yesterday when i was charging one of batteries it switched to default charging mode (1A) for a 800mAh eneloop . Most likely there was no proper connection and the charger stoped charging, then after some time connectioion got enough for charger to recognize putting battery in slot so it started chargin it.

Hope that explains some things, and sorry for bad photo quality as i only have a camera on my mobile phone.


----------



## clintb

For those having problems with AAA's springing back out, I've found an insertion method that has not failed me yet on both of my C9000's.

Insert the negative end first, and push back on it slightly when inserting the positive end. Once snapped in, give the cell a gentle roll from side to side, as if you're spinning it along the lengthwise axis. Doing so will make the negative contact move more towards the center of the cell's negative end.


----------



## Bones

The method described by clintb works for me as well jozek.

The trick is to keep to keep the negative tang compressed while slipping the positive end of the cell into place. The positive post of the AAA cell also has to slip past the protrudence in the center of the positive tang. It helps keep the cell in place.

For what it's worth, the negative tangs will become easier to compress after they've been used for a while. In fact, you can help this along by deliberately compressing them a few times with a rod that's small enough to fit through their openings. A wooden stick whittled to shape will work quite well. It also won't scratch or otherwise damage the tang or the charger providing you don't get carried with the amount of force used.

Please note that the positive tangs are locked into place, so don't attempt to compress them.

More on loading the MH-C9000:

http://www.candlepowerforums.com ... post2810241
.


----------



## TorchBoy

clintb said:


> Insert the negative end first, and push back on it slightly when inserting the positive end. Once snapped in, give the cell a gentle roll from side to side, as if you're spinning it along the lengthwise axis. Doing so will make the negative contact move more towards the center of the cell's negative end.


I do that also, to make sure it isn't going to pop out again (which I very occasionally get).


----------



## 45/70

I think it may be important to note, that the newer C9000's (0I0IA, at least) have a substantially different negative contact for AAA cells than the older models. It really shouldn't work that differently, but does seem to.

At first glance the new ones appear like a flat screwdriver blade, as opposed to the angled bent strip like the old ones have. Actually the new ones are also a bent strip, but are bent more into a 180 degree loop sticking straight out, rather than at an angle. I hope that description makes some sense. A picture isn't possible for me right now.

The newer version seems to be more "picky" about AAA insertion. I find that just inserting them like clintb described works well, but leave out the twisting motion. If I just snap them in and leave it at that, it seems to work better. When I twist the cells (as I am in the habit of doing), they seem to loose contact.



TorchBoy said:


> I do that also, to make sure it isn't going to pop out again (which I very occasionally get).



This doesn't seem to be a problem with the newer version. I imagine that is why the contact is more straight on, rather than angled. There is no tendency for the cells to pop out.

Dave


----------



## Mr Happy

For some reason the contacts for AAA cells seem to be the weak point about the C9000. I have no idea why Maha seems to struggle with this.

For what it's worth, the old negative contact style would have been fine if only the height of the spring had been raised a bit, so that it contacted with the middle of the cell instead of the bottom.

Totally changing the shape of the metal spring as has apparently been done with the newer models does not really address the original problem.

It seems like Maha know what they are doing with electronics, but totally fail when it comes to mechanicals.


----------



## Bones

There may actually be three iterations of the negative tang for the AAA cell 45/70. 

The first, with a decided down angle to the horizontal portion of the tang. A second, with less of a down angle. And, finally, a third with less of a down angle, but also with the same protrudence that has always been formed into the negative tang for the AA cell.

These images might help illustrate what we're saying, the latter two were provided by jazek in post 1:




-





-
-





If you're really having problems keeping AAA cells seated, and you're willing to open up your MH-C9000, it is possible to raise the negative tang in it slot by decreasing the down angle of the horizontal portion of the tang.

If nothing else, perhaps Maha will finally see fit to simply extend the length of the upright portion of the tang a few millimeters. It's hard to believe they actually thought to modify the tang by adding the small protrudence that's always been formed into the AA tang without thinking to raise it a bit as well.


----------



## jozek

Thanks for all feedback about this problem, but everyone concentrates on negative end contact problem, but its not the case here. Negative end contakt is fine and very steady, its the positive end that gives problem. 

Compare the shape of positive tans on those two pictures (no big hill in the middle ). On mine there is nothing to hold call in place and it have a tendency to slide on tang upwards and loosing contact there. This is not a prolem with negative end. Rotating pushing batteries up a bit, nothing makes 100% sure that you wont loose contact. Even stomping on the floor with foot can make it stop charging :/








Bones said:


> -


----------



## TorchBoy

jozek said:


> Compare the shape of positive tans on those two pictures (no big hill in the middle ). On mine there is nothing to hold call in place and it have a tendency to slide on tang upwards and loosing contact there.


Could it be that a machining step was somehow missed?


----------



## Mr Happy

jozek said:


> Thanks for all feedback about this problem, but everyone concentrates on negative end contact problem, but its not the case here. Negative end contakt is fine and very steady, its the positive end that gives problem.
> 
> Compare the shape of positive tans on those two pictures (no big hill in the middle ). On mine there is nothing to hold call in place and it have a tendency to slide on tang upwards and loosing contact there. This is not a prolem with negative end. Rotating pushing batteries up a bit, nothing makes 100% sure that you wont loose contact. Even stomping on the floor with foot can make it stop charging :/



I think you should communicate your problems directly to Maha and see if they can help. If you have a faulty unit they may replace it.


----------



## Tuikku

I found this MH-C9000 from eBay for ~70$ including shipping to Finland.
Is eBay smartest place to get it? Must have worldwide shipping with decent price.


----------



## Mr Happy

Tuikku said:


> I found this MH-C9000 from eBay for ~70$ including shipping to Finland.
> Is eBay smartest place to get it? Must have worldwide shipping with decent price.


Maha has a worldwide distribution network. You should be able to find it in Europe or even Finland without having to resort to eBay. You might try contacting Maha to locate a vendor nearest to you.


----------



## Tuikku

Mr Happy said:


> Maha has a worldwide distribution network. You should be able to find it in Europe or even Finland without having to resort to eBay. You might try contacting Maha to locate a vendor nearest to you.



Thanks, I´ll try to get in touch with Maha.
Still betting it will cost around 100$+ in here, if even available :sigh:


----------



## Mr Happy

Tuikku said:


> Thanks, I´ll try to get in touch with Maha.


Not quite Finland, but one step away: http://www.mahaenergy.se/


----------



## Turbo DV8

jozek said:


>


 
The C9000 I received from NewEgg recently has both the improved AAA negative tang, and the positive contact looks like the one above, without the "dividing" ridge between the two sets of dots. The ridge would tend to hold the AAA cell in place between it and the lower set of dots without having to press it so hard that it is actually under the two lower dots to hold it in place. I did note that when inserting AAA cells, it seemd a good bit of force was needed to make them feel secure, but now when i get home from work I will check my cells to be sure they were not damaged. Will report back. Point is, it is looking like perhaps the newest versions have an improved AAA negative contact , but a worse positive contact for AAA. If this damages my AAA cells also, I will be speaking to Maha about this, my _second_ attempt to give the C9000 a chance.


----------



## Tuikku

Mr Happy said:


> Not quite Finland, but one step away: http://www.mahaenergy.se/



Thanks for link. I found one retailer with price on webpage - 92$ + shipping.
About the same in Germany + shipping.


----------



## fishinfool

Aloha! I know that most people prefer to discharge their cells first before doing a break-in or refresh and analyze. My question is that is there anything wrong with discharging cells at 100ma other that it takes forever to do so? Thank you.


----------



## SilverFox

Hello Fishinfool,

Nothing wrong with that at all.

Tom


----------



## fishinfool

SilverFox said:


> Hello Fishinfool,
> 
> Nothing wrong with that at all.
> 
> Tom


 
Thank you sir! lovecpf


----------



## TakeTheActive

fishinfool said:


> ...My question is that is there anything wrong with discharging cells at 100ma other that it takes forever to do so?


IMHO, you're OVER-THINKING this (new hobby of yours). 

There's a proper time-and-place for Discharging @ 0.2C, 1.0C, 0.5C and 100mA - it all depends on what you're attempting to accomplish... :thinking:


----------



## GAReed

heed experiance; follow a masters advice and TTA's links... you won't be disappointed.
regards,
a noob 



fishinfool said:


> Thank you sir! lovecpf


----------



## larcal

Hello,

My apologies for posting this originally in the parent forum. Very negligent of me! I'm sure we all read at one time Nlee's Amazon review of this Maha, in which he says he could not charge several year old AA's that still had a 1000 mah capacity as measured on his LaCrosse. (His LaCross will charge them). This because the Maha rejects cells of a certain level of resistance, for some mysterious safety reason. Have you all found this to be true?. Maybe his maha was defective. Not talking about cells with a low voltage. Seems like the charger for me otherwise. 

Thanks
Larc


----------



## Mr Happy

larcal said:


> Hello,
> 
> My apologies for posting this originally in the parent forum. Very negligent of me! I'm sure we all read at one time Nlee's Amazon review of this Maha, in which he says he could not charge several year old AA's that still had a 1000 mah capacity as measured on his LaCrosse. (His LaCross will charge them). This because the Maha rejects cells of a certain level of resistance, for some mysterious safety reason. Have you all found this to be true?. Maybe his maha was defective. Not talking about cells with a low voltage. Seems like the charger for me otherwise.
> 
> Thanks
> Larc


Hi, Welcome to CPF

:welcome:

Your question actually has been answered in the other thread, so it's best to continue there. If you ever post a question in the wrong place, just ask a moderator to move it. That's better than posting the same question in two different places.


----------



## TinderBox (UK)

Just bought one of these after the great reviews and details from this thread , it has an *0J0CA* version number.

I am now doing a capacity test on some cheap 7dayshop re-brand AA 2100mah lsd battery.

I have previously done a capacity check on these using my Thunder AC6 and got a capacity of only around 1850mah at a 0.2c discharge rate, so not very good. 

I will be interested in seeing the results from the C9000

Thanks

John.


----------



## lee5079

I just got my MH-C9000 last Friday and has been doing the Battery Charger Operator works for the last couple of days... Phew.. this hobby is really a weird one. 

I get the charger with the thought of placing a bet on it that it could actually salvage some of my NiMH that failed pre-maturely especially like under 1 year of services. They were charged in combination of chargers, including Sanyo's smart charger that with refresh, Sony's smart charger, GP timer based charger and Duracell's Pile Charger ( which I suspected is a timer based charger with dual inline series charge ).

The 30++ batteries pool that I have including Powerexx, Sanyo, Sony & Duracell.

So far, only 4 out of them can be put into the charger and get them into running with the program and I have done them with R&A, Discharge, Cycle with only manage to crank up around 1800mAH from a 2500mA Powerexx. Minimum numbers of the batteries (around 5 out of the 30+ )are reporting HIGH after initial test but the remaining are in an Uknown stage.

When I put the battery / batteries into the slot, the charger recognized it and let me select the programming, but no matter which that i chosen, the slot will get "reseted" and back to square one asking me to program again like a new battery has been just inserted. It doesn't report HIGH nor any error nor doing any programmed activities but just kept reseting on the slot. Have tried the batterries in other slots with same behavior and putting a known good / new batteries will yield a good response and start the activities after the programming done.

My questions are.
- Anyone experienced the same scenario ?
- Am I getting a bad charger ?
- If it is not report HIGH and Not performming programmed activities.. are those batteries good or bad ? Can they be salvaged ?

Hoping some can elighten me on this.

Thank in advance,

Lee.


----------



## Mr Happy

I think the batteries where the slot resets without starting are worse than "HIGH".

It is generally quite difficult to do much to recover batteries once they have developed such high resistance. There is no way to get the resistance back into the normal range once this has happened. Most people consider such batteries "crap" and they either discard them or they relegate them to light duties such as remote controls.

The C9000 is much more useful for maintaining new batteries and keeping them in good condition. If you wish to stop your new batteries going bad the C9000 is the perfect tool to help.


----------



## MarioJP

Speaking of internal resistance I still have those crap energizers, even though they are in bad shape interesting enough is the capacity is still useful to be used in a battery pack. I just look at them as rechargeable alkalines lol. Most chargers refuse to charge them but the la crosse gives me the capacities for these cells of 2000 out of 2200 rated capacities some are 2450 and 2500. But they all report back 2100.

and I have cycled them a few times seems to improve a bit. I don't think the charger is bad but rather the cells are going crap. You can try cleaning the contacts see if that helps but who knows. Maybe its time for those cells to be recycled?


----------



## 45/70

Welcome to CPF lee5079! :thumbsup:


lee5079 said:


> - If it is not report HIGH and Not performming programmed activities.. are those batteries good or bad ? Can they be salvaged ?



It has been a while since I had any cells demonstrate that behavior. Mr Happy is right, it is an indication that the cells are in really bad shape.

I realize you said you could not get any program to work, but did you try "DISCHARGE"? If you insert one of these cells and set the C9000 to discharge @100mA and it works, there may be some hope. I remember having some very old NiCd cells that behaved like that. I can't remember if they could be discharged on the C9000 though. If you can get a 100mA discharge to work, partial recovery may be possible. As Mr H alluded to however, the process is a lot of trouble and the chances for success are slim.

Dave


----------



## Turbo DV8

Yesterday my C9000 did an odd thing. I put a pair of cells on to cycle 2x. Both cells first cycle rendered 1700-ish mAh, but the second cycle of one cell returned around 200 mAh. A subsequent removal, reinsertion, discharge and R&A of the latter cell returned back in the 1700 mAh range. Just a case of bad contact? Or...?


----------



## lee5079

Mr. Happy, 45/70,

Thanks for the reply + welcome, wanted to reply this last night at home ( my time is GMT +8 ) but my ISP is pretty bad that i couldn't even sign in.

I have read the previous long ver 1 thread but not this one.. hopes to go through them when have the chance and the information here was one of the deciding factor for me to get the charger. I was initially wanted to design my own "ultimate brilliant charger" ( I still do now ) but thought the C9000 will do the job for me.

45/70, those batteries returned an immediate DONE on discharge even at 100mAH is chosen. So, pretty no hope but I managed to cheat the charger to bypass the checking ( I am a Firmware Engineer myself and I managed to figure out how most designer will forgot how to handle certain cases after few key pressed last night  ). Hopefully the charger is smart enough to avoid overcharging those high resistance cell while I am forcing them to cycle on low current charge / discharge. Anyway, this experiment will be carried on later as I terminated the cycle after I knew I can cheat the charger... This is to give way to other batteries to be tested.

I have collected a series of googled information hoping that one day i can get my lazy butt up to design some special charge / discharge stuffs that work better. Examples are reading someone's post that we can do some slow discharge + Rest + short charge + Rest + slow discharge + Rest + short charge repetitive cycles which will "hopefully" breakdown some large crystallite and reducing the internal resistance. 

So far, I have my fellow photographer friends to donate their unwanted NiMH to me so that I have a pool of samples to play with. .. what am I getting myself into this time ... and let see how long this will go before I am getting bored and put it aside and just use the charger


----------



## InHisName

lee5079 said:


> So, pretty no hope but I managed to cheat the charger to bypass the checking ( I am a Firmware Engineer myself and I managed to figure out how most designer will forgot how to handle certain cases after few key pressed last night  ). ...


I cannot recall hearing that there is a way found yet, please tell the details to how to 'cheat' the HIGH etc. 

I am not too sure of the usefulness as the 100Ma charge is really 2Amp - 5% of the time charge. A better charger for these junk cells would be a 100ma continuous charge 100% of the time. Finding a charger that does INDIVIDUAL cells @ 100Ma isn't easy.


----------



## lee5079

InHisName said:


> I cannot recall hearing that there is a way found yet, please tell the details to how to 'cheat' the HIGH etc.
> 
> I am not too sure of the usefulness as the 100Ma charge is really 2Amp - 5% of the time charge. A better charger for these junk cells would be a 100ma continuous charge 100% of the time. Finding a charger that does INDIVIDUAL cells @ 100Ma isn't easy.



Hmm.. I wonder if this "feature" will be removed after MAHA see this . 
What I did was to put in a good battery and select the intended program, let the initial checking do all the works. 
- Next, select a slot that are having at least completed 2 cycles or more. (this seems like a Prerequisite actually)
- Press the UP or DOWN arrow key and hold. You will see it is busy switching between the CYCLEs
- While doing the button HOLD, swap in the battery which the Charger rejected earlier.
- Release the hold button. I managed to get this to cheat the charger that it doesn't detect the battery is changed. 

Not sure if a fast replace is needed but so far it works for me. The steps could be simpler but I didn't manage to get this to work until I try it with a Up and Down on a slot which have different cycle displayed.

I have suspected the battery detection used in this Charger is based on polling and not an interrupt based design and hence making the Charger Busy while swapping the battery would be a loop hole.


----------



## InHisName

I tried on mine but it kept cycling no matter what I tried. Holding down on down arrow button, up arrow button, enter all after one cycle of display would move to the next slot and start displaying that one. Pressing and holding the slot button makes it cycle quickly between batt slots.

No matter how quickly or which button holding, I get the prompt to setup new battery settings. This happens each time I insert the 'bad' battery to fool the C9000.

I have revision: 0G0B01 on back above 'made in japan'


----------



## Mr Happy

A way of tricking the charger that other people have used is to insert the bad battery in the slot and then "piggy back" this battery with a good battery using small pieces of foil or thin wire held in place with the fingers. Then program the slot to the desired charge program. The good battery will cause the initial resistance check to succeed and then this battery can be removed allowing the charge program to continue with the bad battery.

Be aware however, that if you attempt to charge a high resistance battery at a normal charge current it may get very hot.


----------



## Battery Guy

*Re: Maha MH-C9000 SUPPORT Thread*



willchueh said:


> *What is the maximum capacity supported by the MH-C9000?
> *
> The maximum capacity supported is 20,000mAh making it compatible with future technologies.



When one considers that this charger is limited to charging AAA and AA NiCd and NiMH cells, I find this statement extremely amusing. A 20mAh AA NiMH cell! 

I think that this guarantees that the MH-C9000 will be compatible with the NiMH technology until our universe experiences heat death.

Kudos to Maha for making this a selling point for their product!

Cheers,
BG


----------



## 45/70

Unfortunately, waaay back with the first major revision of the C9000, about when they added the 50 Watt HID backlight for the LCD, they revised this figure to 4000mAh. If you'd read the entire thread BG, you'd already know this! After all, it's only 547 posts! 

Dave


----------



## Battery Guy

45/70 said:


> Unfortunately, waaay back with the first major revision of the C9000, about when they added the 50 Watt HID backlight for the LCD, they revised this figure to 4000mAh. If you'd read the entire thread BG, you'd already know this! After all, it's only 547 posts!
> 
> Dave



My bad. I knew it was a risk to post to a thread with so many posts, but I really did attempt to make it a semi-legit post.

Seriously, this looked like a really good thread and I started reading through it. I even searched this thread for the word "future" to make sure that nobody else had commented on the whole 20,000 Ah issue. But I totally missed the change from 20 to 4 Ah capacity limit. There is a chance (albeit limited) that my son might see a 4 Ah AA NiMH cell in his lifetime. Probably about the same chance that he will see a 4 Ah 18650 lithium-ion cell, but I digest.....

Now I need to go back and read more about this 50 Watt HID backlit display.

Sorry for not contributing anything useful to this thread. 

Cheers!
BG


----------



## tandem

My 0J0DA rev C9000 comes with the "HID" backlight (I love that glow in my otherwise dark office) and a manual that still claims 20,000mAh supported capacity.

I'm happy to forgo reading the *entire* thread, ignore the errata, and live in a delusional world of NiMH AA cells with titanic capacities. Can't wait for the 8,000mAh AAAs!


----------



## Bones

tandem said:


> My 0J0DA rev C9000 comes with the "HID" backlight (I love that glow in my otherwise dark office) and a manual that still claims 20,000mAh supported capacity.
> 
> I'm happy to forgo reading the *entire* thread, ignore the errata, and live in a delusional world of NiMH AA cells with titanic capacities. Can't wait for the 8,000mAh AAAs!



Why wait when you can use the break-in mode now to analyze, slow charge and check the capacity of your C & D-cells.

And if you (ahem) happen to have a first release of the MH-C9000, you can use this set-up to actually bring its full slate of modes to bear on C & D-cells, including charging up to 20000mAh cells at its maximum rate:



Black Rose said:


> Well here's my latest invention, based on ideas I've gleaned from others on this forum.
> 
> 
> 
> 
> 
> 
> 
> 18 gauge copper wire with #8 ring terminals soldered on the ends.
> Hardwood dowels with electrical tape on the ends (in case there is any moisture in the wood).
> 
> 1/4" nickel plated rare earth magnets hold the ring terminals to the positive and negative ends of the batteries.
> 
> The D cell holders that are available locally are $5 a piece and have 22 or 24 gauge wire attached.
> 
> The holders I really want are too expensive to obtain at the moment, so this will suffice for now.


----------



## lee5079

InHisName said:


> I tried on mine but it kept cycling no matter what I tried. Holding down on down arrow button, up arrow button, enter all after one cycle of display would move to the next slot and start displaying that one. Pressing and holding the slot button makes it cycle quickly between batt slots.
> 
> No matter how quickly or which button holding, I get the prompt to setup new battery settings. This happens each time I insert the 'bad' battery to fool the C9000.
> 
> I have revision: 0G0B01 on back above 'made in japan'



I gave it another tried with 2 of my HIGH battery using the method and it seems still working for me. Even just press and hold the SLOT button works for me. I forgot to note down my unit's revision. 

What Mr. Happy stated was one of the thing I have in mind to try before I getting the stuffs to work using keypressed. Parallel the cells so that the high resistance test will have past in the first place before removing the good one.


----------



## Bones

Mr Happy said:


> A way of tricking the charger that other people have used is to insert the bad battery in the slot and then "piggy back" this battery with a good battery using small pieces of foil or thin wire held in place with the fingers. Then program the slot to the desired charge program. The good battery will cause the initial resistance check to succeed and then this battery can be removed allowing the charge program to continue with the bad battery.
> 
> Be aware however, that if you attempt to charge a high resistance battery at a normal charge current it may get very hot.



Thanks Mr Happy, I hadn't heard of this technique before now. It may provide a viable way to bring the MH-C9000's versatility to bear to recover cells that have slipped over the 'HIGH' threshold due to a lack of conditioning.


----------



## Bones

InHisName said:


> ...
> 
> I have revision: 0G0B01 on back above 'made in japan'



Interesting, has MahaEnergy changed the manufacturing locale of the MH-C9000, or does it actually read Taiwan?


----------



## Turbo DV8

Bones said:


> And if you (ahem) happen to have a first release of the MH-C9000, you can use this set-up to actually bring its full slate of modes to bear on C & D-cells, including charging up to 20000mAh cells at its maximum rate:


 
I've twelve Powerex D-cells that I would love to finally be able to do this to, but apparently I have the 4Ah limit on my C9000. If I wanted to pick around the BST forum, what serial number/rev, etc. should I be looking into over there if I want tos score an earlier 20Ah C9000? Other than that current limit and the backlight, and IIRC, a 1.0 V discharge cutoff as opposed to 0.9 V, any other differences?

Any thoughts on the little issue I posted in post #540?


----------



## Bones

Turbo DV8 said:


> I've twelve Powerex D-cells that I would love to finally be able to do this to, but apparently I have the 4Ah limit on my C9000.
> ...



Don't forget that yours still has the 20000mAh setting in the break-in mode, so if you utilize a timer and set the capacity to 11000mAh, you can effectively bring a standard or 0.1C charge to bear for up to sixteen hours. You can also, of course, utilize the full break-in cycle and the straight discharge mode.



Turbo DV8 said:


> ...
> If I wanted to pick around the BST forum, what serial number/rev, etc. should I be looking into over there if I want tos score an earlier 20Ah C9000?
> ...



You definitely want it to state 0FAB01 on the label. However, since MahaEnergy introduced the first revision on the fly, so to speak, some chargers bearing 0FAB01 on the label actually received the revision. Keeping this in mind, the easiest way to identify a first edition is to make sure it has the appropriate label and charges a quality cell like the Eneloop well past 1.47 volts.

Here's an actual image of the label on my first edition MH-C9000:

http://www.candlepowerforums.com ... post3072027



Turbo DV8 said:


> ...
> Other than that current limit and the backlight, and IIRC, a 1.0 V discharge cutoff as opposed to 0.9 V, any other differences?
> ...



Yes, the big one is that rather than a peak voltage algorithm and a two hour top-off charge, the original edition utilizes a true -dV termination protocol. This directly effects both the minimum rate of charge you can safely employ and the temperature of the cells during the latter stages of the charge at higher rates.

As well, it removes the load during voltage readings while discharging, which substantially delays the process. On marginal cells, the voltage keeps rebounding when the load is removed, so it keeps trying to discharge them further even though there is no real capacity remaining.



Turbo DV8 said:


> ...
> Any thoughts on the little issue I posted in post #540?



Sorry, no, other than ghosts in the machine or just your damnable luck with electronics...


----------



## Bones

45/70 said:


> Welcome to CPF lee5079! :thumbsup:
> 
> It has been a while since I had any cells demonstrate that behavior. Mr Happy is right, it is an indication that the cells are in really bad shape.
> 
> I realize you said you could not get any program to work, but did you try "DISCHARGE"? If you insert one of these cells and set the C9000 to discharge @100mA and it works, there may be some hope. I remember having some very old NiCd cells that behaved like that. I can't remember if they could be discharged on the C9000 though. If you can get a 100mA discharge to work, partial recovery may be possible. As Mr H alluded to however, the process is a lot of trouble and the chances for success are slim.
> 
> Dave



This harkens me back to the termination problems we encountered with the original release of the MH-C9000. It seems that MahaEnergy just plain lacks an array of cells that are truly crap to test their designs with.

Perhaps we should send William Chueh a broad selection. He can then design in the appropriate response so we don't encounter this rather odd behavior when the worst of the worst cells are inserted.


----------



## 45/70

Battery Guy said:


> Sorry for not contributing anything useful to this thread.



Um, BG, you did realize I was just messin' wid ya, right? :thinking:



tandem said:


> and a manual that still claims 20,000mAh supported capacity.



As far as the "manaul", as it is referred to on the back of the C9000, I think both the .pdf and the printed version, have remained unchanged since the very first chargers were released. This also was discussed some number of pages back in this thread. I haven't checked either version in a while, maybe they are updated now.



Turbo DV8 said:


> Any thoughts on the little issue I posted in post #540?



Turbo, I think mine show a quirk every once in a while. I have been just attributing it to the variable mains power out here in the country. I doubt if it is of any concern. If something consistent keeps showing up, I'd just give Maha a call and see what they say.



Bones said:


> It seems that MahaEnergy just plain lacks an array of cells that are truly crap to test their designs with.



Gee, I wonder why that is? Everybody should keep at least a few crap cells that aren't good for much anything, right? 



Bones said:


> Perhaps we should send William Chueh a broad selection. He can then design in the appropriate response so we don't encounter this rather odd behavior when the worst of the worst cells are inserted.



I'm sure that would really make his day. 

Dave


----------



## Turbo DV8

45/70 said:


> Gee, I wonder why that is? Everybody should keep at least a few crap cells that aren't good for much anything, right?


 
Thing is, what is one man's crap, is another man's candlepower. I have (and use) many "crap" cells to power my hallway LED candles, all night, every night for three weeks on a charge. I just can't charge them on the C9000. Admittedly, that type of low-drain application is about all they're good for!


----------



## mellowman

tandem said:


> My 0J0DA rev C9000 comes with the "HID" backlight (I love that glow in my otherwise dark office) and a manual that still claims 20,000mAh supported capacity.
> 
> I'm happy to forgo reading the *entire* thread, ignore the errata, and live in a delusional world of NiMH AA cells with titanic capacities. Can't wait for the 8,000mAh AAAs!



I recently bought one and have the same rev, OJODA. The manual states 20,000mAh supported and max charge rate of 2,000mA. The break-in menu can be set to 20Ah and the charge menu can be set to 2A.

Not sure where the 4Ah limitation is supposed to show up. Maybe it doesn't exist anymore, or maybe never did.


----------



## digitor

mellowman said:


> I recently bought one and have the same rev, OJODA. The manual states 20,000mAh supported and max charge rate of 2,000mA. The break-in menu can be set to 20Ah and the charge menu can be set to 2A.
> 
> Not sure where the 4Ah limitation is supposed to show up. Maybe it doesn't exist anymore, or maybe never did.



.


----------



## 45/70

mellowman said:


> I recently bought one and have the same rev, OJODA. The manual states 20,000mAh supported and max charge rate of 2,000mA. The break-in menu can be set to 20Ah and the charge menu can be set to 2A.



As I stated in my last post, the online manual, and as far as I know, the included instructions with the charger, have remained unchanged since the charger was first introduced.

For example, the online .pdf manual states that the discharge termination voltage is 1.00 Volt. The first, or maybe second revision of the charger, which occurred sometime in 2007, changed this to 0.90 Volt. Also, I believe that during this revision, the 4000mAh and 1.47 Volt charging limits were introduced, along with the addition of the _much_ brighter backlight.



> Not sure where the 4Ah limitation is supposed to show up. Maybe it doesn't exist anymore, or maybe never did.


 As I understand it, It will show up when attempting to charge a cell using any charging function other than "break-in". As far as I know the revised chargers will exceed the 4000mAh limit using the "break-in" mode, as I used to form Sanyo 2700mAh AA cells with my C9000's, I have to admit though, I never noticed the readout. :candle:

Just out of curiosity, does your 0J0DA (those are zeros by the way, not "O''s) refer to the "manaul" on the back label, or to the manual?

Dave


----------



## SilverFox

Hello Melloman,

The C9000 has a 20000 mAh limit on the Break-In function, and a EDIT: this is supposed to be 4000 mAh ENDEDIT 4500 mAh limit on the other charging rates.

Tom


----------



## Battery Guy

45/70 said:


> Um, BG, you did realize I was just messin' wid ya, right? :thinking:



Totally! No worries.


----------



## mellowman

45/70 said:


> Just out of curiosity, does your 0J0DA (those are zeros by the way, not "O''s) refer to the "manaul" on the back label, or to the manual?
> 
> Dave



0J0DA is from label on the back or beneath charger. Don't think there are any rev indicator in the manual.



SilverFox said:


> Hello Melloman,
> 
> The C9000 has a 20000 mAh limit on the Break-In function, and a 4500 mAh limit on the other charging rates.
> 
> Tom



Are you sure? There is no setting for capacity in the other modes and I thought the charging terminations are determined by voltage.

So you're saying in charge mode the termination is determined by either the bat voltage or the total charger supplied mAh with 4500 mAh being a cutoff for charging? 

What was the reason for this? I could understand limiting to 12,500 mAh as the break-in mode overcharges 60% so 20/1.6 = 12.5. Otherwise there is a mismatch in capabilities. Whats the point of breaking-in some future 4500+ mhA AA when you can't subsequently fully charge it.

Seems to be purposefully limited to generate future sales, even though it will probably be decades for this to be an issue with AA bats.

Still wonder what the thinking here is, if correct.


----------



## Mr Happy

mellowman said:


> So you're saying in charge mode the termination is determined by either the bat voltage or the total charger supplied mAh with 4500 mAh being a cutoff for charging?
> 
> What was the reason for this? I could understand limiting to 12,500 mAh as the break-in mode overcharges 60% so 20/1.6 = 12.5. Otherwise there is a mismatch in capabilities. Whats the point of breaking-in some future 4500+ mhA AA when you can't subsequently fully charge it.
> 
> Seems to be purposefully limited to generate future sales, even though it will probably be decades for this to be an issue with AA bats.
> 
> Still wonder what the thinking here is, if correct.


The C9000 uses a matrix of tests to determine when to end the charge in the normal charge mode, though the MaxV = 1.47 V criterion is most commonly encountered when charging cells like Eneloops.

The reason for including a maximum charge limit is that it is possible for the other tests to give an insufficient end of charge signal, and if the charger continued to supply a charging current indefinitely to a cell at a high rate the cell could overheat and cause damage to the charger, in addition to destroying the cell.

Since there is no possibility of an AA NiMH cell having a capacity greater than 3000 mAh, the 4500 mAh limit is only upsetting to people who wish to contrive systems for charging high capacity C or D cells.


----------



## mellowman

Thanks, I can see the point of 4500mAh limitation.

However, the 20,000 mAh in break-in mode goes against these points.

Seems Maha wants to have their cake and eat it too by marketing future capability but not be liable for it by actually providing it.


----------



## lee5079

I have a bunch of donated AA batteries that my fellow photographer friends set aside waiting to dispose them to the recycle collection bin. 

Now I have a dilemma if I should returns those batteries to them and telling them the batteries are good but their charger / use cases are not. :laughing:


----------



## SilverFox

Hello Mellowman,

I believe an original intent was to have the ability to charge and break in C and D cells on the C9000. When there were "issues" with the original algorithm, the settings were changed where needed. 

Tom


----------



## 45/70

SilverFox said:


> Hello Melloman,
> The C9000 has a 20000 mAh limit on the Break-In function, and a 4500 mAh limit on the other charging rates.



I thought it was 4000mAh. Oh well, maybe it is 4500. I've never charged a 4000mAh AA cell anyway. 



mellowman said:


> 0J0DA is from label on the back or beneath charger. Don't think there are any rev indicator in the manual.



Yes that is where the date code is, and as I said, the manual has not been updated that I'm aware of since the first one. Therefore, there would not be _any_ revisions. My question was if the newer C9000's still say



> READ MANAUL FULLY BEFORE OPERATING


as on the label of my 0F0IA, two 0H0FA, and 0I0IA, "manual" has been misspelled. No Biggie, just curious.

Dave


----------



## SilverFox

Hello Dave,

You are correct. The maximum charge limit is 4000 mAh.

Tom


----------



## fishinfool

Ok I give up, :hairpull: where does this "maximum charge limit of 4000 mAh" come from? I don't see it on my instruction manual or anywhere on both my c9000's. I must be going blind!


----------



## SilverFox

Hello Fishinfool,

You may find this thread informative...

Tom


----------



## fishinfool

Mahalo Nui Loa Tom! :wave:


----------



## hagbard

Just bought this charger, and I'm a total newbie and find the instructions a bit confusing, so I'll blast off a few questions:

1. When using Burn-in, it asks for "Set Battery Capacity". Would I be right in assuming I set it to the stated capacity on the battery, which if 2000mAh I'd set it to 2000mAh. Asked in another forum and they said set it to 1000mAh, which is the discharge rate?

2. When completed my batteries have reported voltage of 1.46v not 1.2v, is that normal?

3. When using "Charge" do I manually set the "CHG Rate" to the rate printed on the battery, use the settings it sets up automatically, or the "discharge rate"?

thanks.


----------



## Anders

Hello Hagbard.

Welcome to CPF:wave:

1. Set it at the rated capacity, 2000 mA with your cells.

2. Thats normal.

3.When you are not in a hurry, set the charge rate at somewhere between 0,5-1,0 C. With your type of cells (2000mAh) I would have choosen 0,5-0,7 C which is with your cells 1A- 1,4A per cell.

If you dont touch any buttoms, the charger charge your cells with 1A which is ok with your cells.

Anders


----------



## pae77

hagbard said:


> Just bought this charger, and I'm a total newbie and find the instructions a bit confusing, so I'll blast off a few questions:
> 
> 1. When using Burn-in, it asks for "Set Battery Capacity". Would I be right in assuming I set it to the stated capacity on the battery, which if 2000mAh I'd set it to 2000mAh. Asked in another forum and they said set it to 1000mAh, which is the discharge rate?
> You set it to the actual stated capacity on the battery label, assuming it is more or less accurate, which in the case of quality batteries is usually the case. The value is used by the charger to calculate the rate at which it is going to charge during the break-in cycle.
> 
> 2. When completed my batteries have reported voltage of 1.46v not 1.2v, is that normal? It's normal for the batteries to come off the charger a little "hot" (as in high voltage, not temperature). Once a load is applied, the voltage will sag to expected levels.
> 
> 3. When using "Charge" do I manually set the "CHG Rate" to the rate printed on the battery, use the settings it sets up automatically, or the "discharge rate"? The general consensus, I believe is that it is optimal to charge at about 1/2 C or 1/2 the actual capacity of the battery. So in the case of a 2,000 mah Eneloop, you would charge at 1,000 ma which is the default the C9000 is set up to charge at if you don't enter anything. If you are in a hurry, it's acceptable to charge at a higher rate, but it's best for the battery to charge at .5 C. Too low a rate and you risk the charger missing termination. Too high a rate and you risk damaging the battery or shortening its useful life. So .5 to 1C is the usual accepted appropriate range, for NiMH and NiCad, imo.
> 
> thanks.



The above is just my opinion based on the reading I have done here and elsewhere.


----------



## hagbard

Okay, I think I got it now. Thanks!


----------



## Boss Hogg

I just performed a discharge followed by the break-in mode for my Sanyo Eneloop AAA's. The final readouts for them were a bit strange, higher capacity than the stated 800 mAh. My cells were:

830mah
811mah

Did I do something wrong, or is this okay? I set the break-in charge rate at .1C.


----------



## fishinfool

Boss Hogg said:


> I just performed a discharge followed by the break-in mode for my Sanyo Eneloop AAA's. The final readouts for them were a bit strange, higher capacity than the stated 800 mAh. My cells were:
> 
> 830mah
> 811mah
> 
> Did I do something wrong, or is this okay? *I set the break-in charge rate at .1C. *


 
Aloha Boss Hogg! Those numbers are a higher than all 36 of my aaa eneloop break-in numbers, but not by much. My average break-in number was 779mah. I had a couple that went up to 813mah so your numbers are just fine IMO.

You said "I set the break-in charge rate at .1C." so did you do a regular 'charge cycle' instead of a 'break-in'? If you did a break-in then you would have had to 'set the battery capacity' which would have been 800mah for aaa eneloops. 

Also, just out of curiosity, what was your discharge rate prior to the break-in?


----------



## Boss Hogg

fishinfool said:


> Aloha Boss Hogg! Those numbers are a higher than all 36 of my aaa eneloop break-in numbers, but not by much. My average break-in number was 779mah. I had a couple that went up to 813mah so your numbers are just fine IMO.
> 
> You said "I set the break-in charge rate at .1C." so did you do a regular 'charge cycle' instead of a 'break-in'? If you did a break-in then you would have had to 'set the battery capacity' which would have been 800mah for aaa eneloops.
> 
> Also, just out of curiosity, what was your discharge rate prior to the break-in?



Thanks. It was a break-in set at 800mah. As for the discharge that was set at 400mah.


----------



## hagbard

Got another question. If the brake-in is interpreted by a power outrage, what then? I got about 31 hours into it, and the power went out and it switched to "Charge". Do I start the brake-in again or just go ahead and charge them?


----------



## 45/70

hagbard, that far along, the C9000 was interupted during the second, and final charge. I would just charge them up and use them. The big drawback is that you don't probably know what the final capacity was, unless you happened to notice. To get that, you'd have to start all over again.

Dave


----------



## hagbard

45/70 said:


> hagbard, that far along, the C9000 was interupted during the second, and final charge. I would just charge them up and use them. The big drawback is that you don't probably know what the final capacity was, unless you happened to notice. To get that, you'd have to start all over again.
> 
> Dave



Okay, I guess this brings me to yet another question, what is the "charge rate"? Haven't charged any batteries yet. Is it the rating on the battery or the "discharge rate"? They're eneloops rated at 2000mAh.


----------



## fishinfool

hagbard said:


> Okay, I guess this brings me to yet another question, what is the "charge rate"? Haven't charged any batteries yet. Is it the rating on the battery or the "discharge rate"? They're eneloops rated at 2000mAh.


 
I normally go with a charge rate of 500ma or 1000ma depending on how quickly I need the batteries.


----------



## hagbard

fishinfool said:


> I normally go with a charge rate of 500ma or 1000ma depending on how quickly I need the batteries.



Okay, so the charge rate doesn't really relate to the capacity of the battery, its how much juice is being delivered at a time. I'll still get the full charge, correct?


----------



## fishinfool

hagbard said:


> Okay, so the charge rate doesn't really relate to the capacity of the battery, its how much juice is being delivered at a time. I'll still get the full charge, correct?


 
It does, it just takes longer to charge when at lower rates.


----------



## TakeTheActive

hagbard said:


> Okay, *I guess this brings me to yet another question, what is the "charge rate"?* Haven't charged any batteries yet. Is it the rating on the battery or the "discharge rate"? They're eneloops rated at 2000mAh.



Both *Anders* and *pae77* already answered that question.

What part of their answers didn't you understand?

Are you interested in investing some personal time and learning about the theory and proper maintenance for your cells?

(No 'touting' this time!)



Anders said:


> Hello Hagbard.
> 
> Welcome to CPF:wave:
> 
> 1. Set it at the rated capacity, 2000 mA with your cells.
> 
> 2. Thats normal.
> 
> *3.When you are not in a hurry, set the charge rate at somewhere between 0,5-1,0 C. With your type of cells (2000mAh) I would have choosen 0,5-0,7 C which is with your cells 1A- 1,4A per cell.
> *
> If you dont touch any buttoms, the charger charge your cells with 1A which is ok with your cells.
> 
> Anders





pae77 said:


> Originally Posted by hagbard View Post
> Just bought this charger, and I'm a total newbie and find the instructions a bit confusing, so I'll blast off a few questions:
> 
> 1. When using Burn-in, it asks for "Set Battery Capacity". Would I be right in assuming I set it to the stated capacity on the battery, which if 2000mAh I'd set it to 2000mAh. Asked in another forum and they said set it to 1000mAh, which is the discharge rate?
> *You set it to the actual stated capacity on the battery label, assuming it is more or less accurate, which in the case of quality batteries is usually the case. The value is used by the charger to calculate the rate at which it is going to charge during the break-in cycle.
> *
> 2. When completed my batteries have reported voltage of 1.46v not 1.2v, is that normal? *It's normal for the batteries to come off the charger a little "hot" (as in high voltage, not temperature). Once a load is applied, the voltage will sag to expected levels.*
> 
> *3. When using "Charge" do I manually set the "CHG Rate" to the rate printed on the battery, use the settings it sets up automatically, or the "discharge rate"? The general consensus, I believe is that it is optimal to charge at about 1/2 C or 1/2 the actual capacity of the battery. So in the case of a 2,000 mah Eneloop, you would charge at 1,000 ma which is the default the C9000 is set up to charge at if you don't enter anything. If you are in a hurry, it's acceptable to charge at a higher rate, but it's best for the battery to charge at .5 C. Too low a rate and you risk the charger missing termination. Too high a rate and you risk damaging the battery or shortening its useful life. So .5 to 1C is the usual accepted appropriate range, for NiMH and NiCad, imo.*
> 
> thanks.
> 
> 
> 
> The above is just my opinion based on the reading I have done here and elsewhere.
Click to expand...


----------



## hagbard

fishinfool said:


> It does, it just takes longer to charge when at lower rates.



Thanks, that was helpful .


----------



## TakeTheActive

hagbard said:


> Thanks, that was helpful .


(I read your ORIGINAL, unedited post too.)

AFAICT, you're a Newbie (just joined CPF, low post count), you're asking basic questions, 2 members gave you detailed answers and you repeated one of your original questions. IMHO, you sound confused and I'm offering to help clear up some of that confusion.

Now, you can continue asking 'Asked-and-Answered' questions, and getting sometimes complete / sometimes incomplete answers. Or, you can invest some of your personal time and read some basic theory - information originally posted by many CPF Gurus.

I'm not looking to insult anyone - I'm just pointing out that reading FAQs are more efficient than posting a Frequently Asked Question and waiting for a random complete / incomplete / right / wrong answer.


----------



## hagbard

I just want to charge my batteries with a minimum of hassle, not be be an expert. I just tired doing the Charge mode, and put in three batteries, every time I do, it sends me back to Mode. Its not accepting more than one battery.

Here's what I'm doing:

1. I put an AAA in slot one, Select Charge mode, press Enter, select 400mAh, press Enter.
2. I then put an AAA in slot two, Select Charge mode, press Enter, select 400mAh, press Enter. 

--> it now goes back to slot one and asks me to select the Mode again?! If I put all the batteries in, go from slot to slot doing the above, it looses all the settings. I think its not working.


----------



## pae77

hagbard said:


> I just want to charge my batteries with a minimum of hassle, not be be an expert. I just tired doing the Charge mode, and put in three batteries, every time I do, it sends me back to Mode. Its not accepting more than one battery.


Then just insert them in the C9000, give it about 4 or 5 hours and your batteries will be charged. Then simply remove your batteries and use them. Despite your statement above, this will work unless your C9000 is defective. But I believe your C9000 is fine and you are simply misinterpreting how it works and what the display is doing and the timings involved.

Simply don't pay any attention to the the confusing (to you) display as it requires some mental effort and knowledge to understand what it is doing and telling you. An effort that you obviously are not interested in making. Just trust that the C9000 will charge your AA and AAA batteries more or less properly with no intervention or input needed from you beyond simply properly inserting the batteries into the charger. Everything else will be taken care of automatically and the charger will use its default charge rate of 1000 ma for AA batteries, and whatever the default is for AAA batteries (probably 400 ma) and that will be fine for most NiMH batteries you are likely to be using.


----------



## tandem

pae77 said:


> whatever the default is for AAA batteries (probably 400 ma)



Nope. 1000 mAh default regardless of battery type for the C9000.

Some reading or intuition is required if you want to get the most out of the C9000 and devices like it. If one doesn't want to learn how to use the device to the optimum, just pretend it has no display, pop your cells in and walk away. They'll get charged.


----------



## hagbard

pae77 Actually, it won't let me do that. When it asks for Mode again, it brings up 1000mAh then goes back and asks for Mode again. Endless loop. 

I think I might have found the problem. Eric at Maha said it doesn't handle older batteries well. I tried four new ones and it works. I then tried the older ones and when I left out one of the batteries it started working, seems to be a bad battery screwing things up. Thought this charger issued a warning (HIGH) if a battery were defective?

I need to get batteries going and have to jump in...I'm sure the more I use it, the more I'll pick up. I just don't have the time to study the fine art of battery maintenance all in one go. I have a handicapped five year old who depends on her batteries.


----------



## bbb74

You might not be fully inserting the aaa bettery into the c9000. Sometimes with the aa's it seems like its in, but its not really. Usually the top isn't quite in, give the top of the battery a good solid push, you might find it clicks in further.


----------



## Mr Happy

hagbard said:


> Here's what I'm doing:
> 
> 1. I put an AAA in slot one, Select Charge mode, press Enter, select 400mAh, press Enter.
> 2. I then put an AAA in slot two, Select Charge mode, press Enter, select 400mAh, press Enter.
> 
> --> it now goes back to slot one and asks me to select the Mode again?! If I put all the batteries in, go from slot to slot doing the above, it looses all the settings. I think its not working.


What Eric told you is correct, but it might not be the only problem.

If the C9000 thinks you have inserted an alkaline battery it will simply refuse to charge it and will keep going back to the mode display again. Very old and bad rechargeable batteries can behave like this. If they do, you really need to recycle them and replace them with new ones.

_*However*_: this is not the only possible problem. Some AAA batteries have a wrapping that curves around the end of the negative end of the battery, and this can prevent the C9000 making proper electrical contact. (Only happens with AAA cells, not AA cells.) This problem has happened to me before now. If your batteries look like this, you should carefully trim back the wrapping with a sharp pair of scissors to expose more metal. Then try again. You will notice that many new AAA cells have a wrapping that does not curve around the negative end and these should be good to go from the outset.


----------



## 45/70

hagbard said:


> Okay, I guess this brings me to yet another question, what is the "charge rate"? Haven't charged any batteries yet. Is it the rating on the battery or the "discharge rate"? They're eneloops rated at 2000mAh.



I use a charge rate of 0.5C for most of my cells, unless I need them charged in a hurry, then I'll go as high as 1C. "C" = the capacity of the cell in mAh, but is expressed in mA, as this is charge current, not capacity. For example, if you have a 1000mAh cell, 0.5C = 500 mA current rate and a 1C rate would be 1000mA. So a 0.5C charge rate for a 2000mAh eneloop AA would be 1000mA which, as already mentioned, is the default rate of the C9000, ie. you don't need to input data, unless you want a different charge rate.

As for the problem you are having with your cells not being recognized by the C9000, it sounds indeed, like you may have some old, or damaged cells suffering from high internal resistance, as Eric said. It could be, as Mr Happy suggested, that the bottoms of the cells are not making proper contact. If I place the negative end of the cell in first, I've had little problems with this. There are apparently, two or three versions of negative contacts used in the C9000, yours may be different than mine.

I would avoid trimming the shrink wrap, if possible, if you run into this problem in the future, as I've had cells short out that didn't have the wrap go around the negative end of the cell a bit. This has only ever happened with Sanyo 900 and 1000's which don't have the wraparound shrink wrap, when used in 3 AAA lights that use a battery carrier. The carrier can shift slightly in the light body and short the end of one of the cells against the body, if the wrap does not go around the end of the cells.

Sounds like you have things under control, now. Enjoy your C9000, it's a great charger/analyzer.

Dave


----------



## TakeTheActive

*It's *REALLY* Up to You...*



hagbard said:


> *I just want to charge my batteries with a minimum of hassle, not be be an expert*. I just tired doing the Charge mode, and put in three batteries, every time I do, it sends me back to Mode...


*Basic, NO FRILLS / NON-TECHNICAL answer:*

When the Maha MH-C9000 '_blinks_' and goes back to MODE, it believes that the cell has an EXTREMELY high Internal Resistance and cannot be recharged. *RECYCLE* (aka properly *TRASH*) it and move on.​*__________________________________________________*​
*More Technical / Informative answer:*

CLICK on my Sig Line LINK and read about "*Maha MH-C9000 Impedance Check Voltage*".​*__________________________________________________*​


pae77 said:


> *Then just insert them in the C9000, give it about 4 or 5 hours and your batteries will be charged*...


*This is not true.* If the MH-C9000 '_blinks_' and continuously returns to MODE, it will *NEVER*, AFAICT, attempt to charge that cell.

Well, to be perfectly honest, the TEST voltage that the MH-C9000 applies to the cell each time it '_recycles / Tests it_', *WILL* impart some MINOR charge to the '_soon-to-be-departed_', '_worn out / neglected / abused_' cell. But, in the *BIG PICTURE*, does it really matter? :thinking:
(Oops! I'm again going off on one of my EXCESSIVE FORMATTING tangents!  )



pae77 said:


> ...*Just trust that the C9000 will charge your AA and AAA batteries more or less properly with no intervention or input needed from you beyond simply properly inserting the batteries into the charger. Everything else will be taken care of automatically and the charger will use its default charge rate of 1000 ma for AA batteries, and whatever the default is for AAA batteries (probably 400 ma) and that will be fine for most NiMH batteries you are likely to be using*.


*This is also not true.* The MH-C9000 will default to a Charge Rate of *1000mA* for *ANY* cell inserted into *ANY* channel that the USER has not changed / programmed before the timeout period expires. IMHO, based on the knowledge I've gained from reading the CPF 'Batteries Included' Archives, 1000mA (aka 1.25C) is TOO HIGH of a Charge Rate for 800mAH AAA cells.*__________________________________________________*​*Disclaimer: *I've NEVER experienced the MODE response from not properly inserting an AAA cell. I *HAVE* experienced it when attempting to charge a *CRAP* cell (AA or AAA).

*Note: *I may be a BLUNT, STUBBORN, "_OLD FART_", but, if you're willing to invest some personal effort, I'm '*ready, willing and able*' to share the knowledge I've acquired from my hundreds of hours of reading the CPF 'Batteries Included' Archives. :wave:

(Note 2: To the '_regular readers_' of 'Batteries Included', please note that I've acknowledged your post(s) regarding my EXCESSIVE use of FORMATTING and, IMHO, have appropriately cut back (ESPECIALLY in the recent Hybrid thread with the medical graduate). Currently, I've been up ~33 hours, trying once again to cure my insomnia and restore my circadian rhythm to the norm of ASLEEP when it's dark, AWAKE when it's light  )​


----------



## pae77

Thanks for the corrections and I'm sorry for any incorrect information I posted.

It's been a while since I charged any AAA's in my C9000 so I forgot about the default charge rate on those. At least I did indicate I wasn't certain what the C9000's default charge rate was for AAAs.

However, 1.25 C while, obviously, not an ideal charge rate, and not one I personally would use, is not going to destroy AAA's in a hurry. For someone who has indicated they don't want to be bothered learning about the finer points of charging with the C9000, I still think it is reasonable under those circumstances to tell them to just insert the cells and let the charger charge at the default rate, especially after the proper charge rate range (.5 to 1 C) was explained several times first, and apparently was not sinking in.


----------



## tandem

Mr Happy said:


> _Some AAA batteries have a wrapping that curves around the end of the negative end of the battery, and this can prevent the C9000 making proper electrical contact. (Only happens with AAA cells, not AA cells.)_


_

Interesting, I'd not noted that before but in AAA size I only have Imedions, Eneloops and "Duraloops".

Of these three only Powerex/MAHA's own Imedion 800 AAA cells have a little (miniscule) amount of wrapping extension beyond the negative end - must be less than a millimetre - and it barely covers the radius of the outside bottom edge of the cell. I've not noted any problems from these, but certainly can remember not inserting AAA cells quite right the first time 'round._


----------



## InHisName

*Re: It's *REALLY* Up to You...*



TakeTheActive said:


> *Basic, NO FRILLS / NON-TECHNICAL answer:*
> 
> When the
> . . . . . .
> *More Technical / Informative answer:*
> 
> CLICK ​


Its good to see this two stage type of answer. The direct 'bottom-line' quick answer. AND the link to the very detailed full explanation.

For some with so little time to spare the sparse answer is good enough. Having a multi colored answer on a formatted platter can still be too time consuming. Now people can do both or just the fast answer as their time fits.

Keep on doing the dual-answer style with formatting.
hagbard: those are likely to be junk cells and c9000 wont charge them. If had tired to charge them they would get very warm or hot! Since you're just getting started you may not have enough eneloops / new cells, so you may need to use these junkers until more replacements are purchased according to your family budget. The ONLY use for mode 'cyclers' is remotes or clocks. If you have a charger that charges AAA & AA in 16 hours, then they can be charged slow enough to not get too hot. 

If an eneloop runs down one of your clocks in 4 months, then a junker might last a month or two at most. A cell that registers HIGH might last 2 or maybe even 3 months in the same clock. 
​


----------



## hagbard

*Re: It's *REALLY* Up to You...*

Just to clarify. The troublesome battery doesn't have any wrapping around the bottom (Energizer) and not very old. Also, when its in any slot, it causes the entire charger to reset, not just the slot its in, which seems odd given they're supposed to be independent. Thanks again guys.


----------



## 45/70

hagbard said:


> Also, when its in any slot, it causes the entire charger to reset, not just the slot its in, which seems odd given they're supposed to be independent.



It's been a while since I tried to charge any cells this bad with the C9000. I think what happens is that it trips up the whole system. This is just as well because it makes you aware that either you are attempting to charge an alkaline cell, or you have a damaged cell.



InHisName said:


> If you have a charger that charges AAA & AA in 16 hours, then they can be charged slow enough to not get too hot.


 
In, I can't say I care too much for some of your posting tips, this is a Forum, not a circus.

Anyway, while it's true that charging cells with a high IR can be accomplished with a 16hr charge, you have to realize that a good part of the charging current isn't actually charging the cell with this method. At a 0.1C charge rate, only a small portion of the current is actually charging the cell, most is lost as heat. I've found that charging at a medium to fast rate where the cells become warm, but not too hot, frequently results in higher capacity, is quicker, and in most cases, works better. The La Crosse series of chargers are fairly good for this purpose.

Dave


----------



## tuan209

hey guys,

I just got the c9000 charger and have some questions. I have some new eneloops that needs to be recharged, so I proceeded with the "break in" mode. I set the capacity to 2000 and noticed that the charger has charged the eneloops up to 2800 mah and it is still going. Is this normal? 

Tuan


----------



## tuan209

Opps dis-regard my previous post. I just read the first page of the thread. Sorry guys!


----------



## 45/70

tuan209 said:


> Opps dis-regard my previous post. I just read the first page of the thread. Sorry guys!



We'll let it slide, this time, tuan. 

While many of us think it's a good idea to run a "break in" cycle on new eneloops, it probably really isn't necessary. That said, I personally do, and repeat a break in every year or so thereafter.

Dave


----------



## hagbard

I'm clearly not cut out for this. I ran a bunch of new batteries on brake-in, and they're lasting way less time they they were when I was using those included cheap chargers. 

For instance, I put two broke in AAs into my Logitech mouse, it reports 30% charge. I put in one's that have been sitting around last charged with the fast charger weeks ago, got 35%. My multi-meter tells me the one's I broke in last week have 1342mAh and the one's I haven't even charged yet have 1368mAh??? These are all Duracell rechargables 2000mAh.

At this point, thinking of returning the charger.


----------



## Quension

hagbard said:


> I ran a bunch of new batteries on brake-in, and they're lasting way less time they they were when I was using those included cheap chargers.



I'll let others answer about the charger, but your measurements concern me:



> For instance, I put two broke in AAs into my Logitech mouse, it reports 30% charge. I put in one's that have been sitting around last charged with the fast charger weeks ago, got 35%.



Usually these devices are calibrated to judge remaining charge based on the voltage depression of a typical alkaline. Since NiMHs have a much flatter discharge curve (they run steady and then drop like a rock), a percentage is impossible to calculate and so the reported number is essentially useless.



> My multi-meter tells me the one's I broke in last week have 1342mAh and the one's I haven't even charged yet have 1368mAh???



How is your multi-meter determining this? Also note that's a difference of 1.9%, which normally doesn't translate to "lasting way less time" in actual usage.

Can you start by describing the problem from the beginning? Such as, how long _are_ they actually lasting?


----------



## shadowjk

Multimeters typically can not measure mAh remaining in a battery. Actually, no meter can do that without discharging the battery to see how much energy comes out.


----------



## Mr Happy

hagbard said:


> I'm clearly not cut out for this. I ran a bunch of new batteries on brake-in, and they're lasting way less time they they were when I was using those included cheap chargers.


What were the Break-In capacity results reported by the charger?



> For instance, I put two broke in AAs into my Logitech mouse, it reports 30% charge. I put in one's that have been sitting around last charged with the fast charger weeks ago, got 35%. My multi-meter tells me the one's I broke in last week have 1342mAh and the one's I haven't even charged yet have 1368mAh??? These are all Duracell rechargables 2000mAh.


Multimeters do not read (cannot read) mAh. How are you getting these numbers?

When batteries come off the break-in cycle they are fully charged. If you have a multimeter, what voltage do the batteries have after the Break-In cycle has finished?

Whether the Logitech mouse says 30% or 35% doesn't matter. The mouse cannot know the battery capacity -- so whatever numbers it reports are unreliable (that is to say, wrong).

As Quension asks, how long do the batteries actually last in the mouse?



> At this point, thinking of returning the charger.


That would seem to be hasty.

Using the C9000 a precise answer can be obtained. If you take a fully charged battery, either from the C9000 or from another charger, you can measure its charge using the Discharge mode (use a discharge current of 500 mA for AA cells). If you do that, what capacity do you get? Do it a few times and/or with a few cells to get a good feel for the averages.


----------



## hagbard

Mr Happy said:


> What were the Break-In capacity results reported by the charger?
> 
> Multimeters do not read (cannot read) mAh. How are you getting these numbers?



Sorry, I was reading the wrong thing, voltage.


> As Quension asks, how long do the batteries actually last in the mouse?


Less than a week before I get the replace batteries message. I used to see my son once every two weeks with the request for batteries for his wireless headphones. Had him up three times last week requesting them (those ones where just charged, no break in).




> Using the C9000 a precise answer can be obtained. If you take a fully charged battery, either from the C9000 or from another charger, you can measure its charge using the Discharge mode (use a discharge current of 500 mA for AA cells). If you do that, what capacity do you get? Do it a few times and/or with a few cells to get a good feel for the averages.


I'd try that but I'm running out of time for the return period ends this week. 

Here's the latest issue. Put three AAAs in Friday morning brake-in mode, this morning, the battery is slot one is done (544mAh), the one in the second is still going, and the one in slot three isn't doing anything. Its not reporting as "done", not in the process at all. The charger just keeps going from slot one to slot two and ignores slot three. 

The charger seems like an undue hassle. It costs $8cdn to buy a four pack of rechargeables, if they die prematurely because I use the included slow charger, seems like a reasonable compromise.


----------



## Quension

Something else occurs to me: you said these were Duracell 2000mAh, but are they identical to the old ones that are lasting longer? Duracell sources its rechargeables from at least two different manufacturers, so look at the "made in <country>" line on the battery itself, and the color of the plastic ring around the + button.

Obviously if this is a hassle and what you had before is working better for you, then no worries. It would just be nice to get to the bottom of the behavior you're seeing.


----------



## hagbard

Quension said:


> Something else occurs to me: you said these were Duracell 2000mAh, but are they identical to the old ones that are lasting longer? Duracell sources its rechargeables from at least two different manufacturers, so look at the "made in <country>" line on the battery itself, and the color of the plastic ring around the + button.
> 
> Obviously if this is a hassle and what you had before is working better for you, then no worries. It would just be nice to get to the bottom of the behavior you're seeing.



They're not the higher quality Japanese ones, they have the black top. Still can't understand why it stopped charging the third battery? Just like there was nothing in that slot.

Correction, they do say "Made in Japan" on them.


----------



## tandem

Push down a little harder on the third battery that appears to be doing nothing? I know when I first started using the C9000 I had one or two not quite fully inserted cells and one stopped charging sometime after I'd inserted it. 

Once I figured that out and how to insert them fully and completely I never again had an issue like that.

If you are certain that the cell was inserted correctly, try it again - remove and wait 10 seconds and then insert it. See if it behaves this time. If not, perhaps you do have a dead cell.

I have dozens of Duraloop "white top" cells and have never once had one die on me but have never experienced the black top cells and don't plan on going there.


----------



## bcwang

Are you sure for break-in mode you set the right capacity of the battery and did not leave it at the default (2500mah)? Also, did you discharge your battery before you started break-in? 

Because if you didn't do those two things, you could have overcharged your battery quite severely causing them to degrade.


----------



## hagbard

bcwang said:


> Are you sure for break-in mode you set the right capacity of the battery and did not leave it at the default (2500mah)?



Nope. Positive.



> Also, did you discharge your battery before you started break-in?


No, I didn't. Am I supposed to?



> Because if you didn't do those two things, you could have overcharged your battery quite severely causing them to degrade.


Why do I need to discharge first? 

Again, the thing that I'm most concerned about is the third battery which was going through the brake-in for over a day, then suddenly it was not.


----------



## pae77

Most people recommend doing a discharge on the batteries before starting the break-in process. If you think about it, it makes sense because the first step in the break-in process charges the batteries.

In fact, a question I always had was why the break-in mode doesn't start with a discharge as part of the programmed break-in process?


----------



## hagbard

Found the answer, no delete here.


----------



## arjay

Just a few weeks ago I got two C9000 units with different firmwares, one 0101A and 0J0CA. With that I got 100 new eneloops and has been running initial discharge and break-in cycles (will post results after I'm done). Now I have noticed that in all 23 sets of 4 that I have run, the third cell almost always have the lowest capacity in both initial discharge and break-in numbers. Is this normal? does anybody else experience this with their units. I wonder if there is something wrong with my two units as I'm planning to get a 3rd and maybe a 4th.


----------



## fishinfool

arjay said:


> Just a few weeks ago I got two C9000 units with different firmwares, one 0101A and 0J0CA. With that I got 100 new eneloops and has been running initial discharge and break-in cycles (will post results after I'm done). Now I have noticed that in all 23 sets of 4 that I have run, the third cell almost always have the lowest capacity in both initial discharge and break-in numbers. Is this normal? does anybody else experience this with their units. I wonder if there is something wrong with my two units as I'm planning to get a 3rd and maybe a 4th.


 
Kumusta Arjay! I just looked at my spreadsheet and a lot of the 3rd cells are lower but not all of them. The ones that are lower are only lower by a little and until you mentioned it, I didn't really notice the difference. 

How much lower are your 3rd cell numbers compared to the others?


----------



## tandem

pae77 said:


> In fact, a question I always had was why the break-in mode doesn't start with a discharge as part of the programmed break-in process?



I'm guessing it's because their display/firmware wouldn't make it easy to report the pre-breakin discharge as well as the break-in discharge and that many battery geeks want to track both.



arjay said:


> ... two C9000 units with different firmwares, one 0101A and 0J0CA ... I have noticed that in all 23 sets of 4 that I have run, the third cell almost always have the lowest capacity in both initial discharge and break-in numbers.



My C9000 has 0J0DA firmware and I do not observe that pattern, nor does slot 1 seem to report higher numbers consistently as some have observed.


----------



## 45/70

tandem said:


> My C9000 has 0J0DA firmware and I do not observe that pattern, nor does slot 1 seem to report higher numbers consistently as some have observed.



Just as info, before you guys get too carried away with it, as far as I know, the "0J0DA" type codes are manufacturing date codes, and have nothing to do with firmware revisions. Of course, if you know when a revision was made, you could determine if a particular unit was manufactured before or after the revision.

Dave


----------



## tandem

Ah, thanks... I've read about the date code hypothesis before and promptly forgot all about it. This does make more sense to me. A product that has made it through its childhood years ought not be getting new firmware all the time, unless battery technology is changing all the time, which it isn't.


----------



## arjay

fishinfool said:


> Kumusta Arjay! I just looked at my spreadsheet and a lot of the 3rd cells are lower but not all of them. The ones that are lower are only lower by a little and until you mentioned it, I didn't really notice the difference.
> 
> How much lower are your 3rd cell numbers compared to the others?



The numbers are not far off but there is a pattern wherein the 3rd cell shows lesser numbers or is in the average. Do those numbers look right to you? Wonder if I'm just too picky. 

Here is a sample of 10 sets of 4

AA Eneloops(Mfd NOV 09) Aug-10
Cells - Initial Discharge - Break-in 1

1 1351 1937 
2 1356 1953 
3 1355 1939 
4 1342 1923 

5 1342 1929 
6 1349 1928 
7 1347 1920 
8 1345 1921 

9 1348 1934 
10 1362 1944 
11 1360 1923 
12 1346 1924 

13 1337 1945 
14 1347 1959 
15 1341 1925 
16 1345 1945 

17 1350 1949 
18 1354 1942 
19 1341 1935 
20 1342 1932 

21 1348 1938 
22 1355 1934 
23 1349 1939 
24 1351 1935 

25 1353 1947 
26 1355 1938 
27 1348 1937 
28 1348 1945 

29 1355 1939 
30 1363 1945 
31 1356 1933 
32 1361 1941 

33 1347 1934 
34 1348 1930 
35 1340 1926 
36 1341 1931 

37 1349 1927 
38 1355 1943 
39 1348 1939 
40 1348 1925 



45/70 said:


> Just as info, before you guys get too carried away with it, as far as I know, the "0J0DA" type codes are manufacturing date codes, and have nothing to do with firmware revisions. Of course, if you know when a revision was made, you could determine if a particular unit was manufactured before or after the revision.
> 
> Dave



Thanks for that piece of info. Makes sense to me.


----------



## uk_caver

My C9000 (just over 3 years old) seems like it may be under-reporting charge for the first slot, which I don't think it used to do.

Just checkimng out some new budget LSDs, I ran 2 sets of 4 through on refresh/analyze (after doing a discharge).

Across all 4 slots and both sets of 4 cells, the discharge figures were pretty close, both on initial discharge, and within the refresh/analyze (within about 40mAh

In the refresh/analyze, on slots 2-4, I was getting pretty much the same out on the discharge as went in on the first charge.
On slot 1, both times, the reported charge on the initial charge was something like 75-100mAh lower than for the other slots.

That would square with the cells being evenly matched, the charging being done consistently across the slots, and the discharge figures being accurate (or at least consistent) on all slots, but with the charge current being measured inaccurately for slot 1.

If that is the case, it's something I can live with, since I only really need consistent charging and reliable discharge measurements, but I was wondering if it could be a sign of future issues.


----------



## fishinfool

arjay said:


> The numbers are not far off but there is a pattern wherein the 3rd cell shows lesser numbers or is in the average. Do those numbers look right to you? Wonder if I'm just too picky.
> 
> Here is a sample of 10 sets of 4
> 
> AA Eneloops(Mfd NOV 09) Aug-10
> Cells - Initial Discharge - Break-in 1
> 
> 1 1351 1937
> 2 1356 1953
> 3 1355 1939
> 4 1342 1923
> 
> 5 1342 1929
> 6 1349 1928
> 7 1347 1920
> 8 1345 1921
> 
> 9 1348 1934
> 10 1362 1944
> 11 1360 1923
> 12 1346 1924
> 
> 13 1337 1945
> 14 1347 1959
> 15 1341 1925
> 16 1345 1945
> 
> 17 1350 1949
> 18 1354 1942
> 19 1341 1935
> 20 1342 1932
> 
> 21 1348 1938
> 22 1355 1934
> 23 1349 1939
> 24 1351 1935
> 
> 25 1353 1947
> 26 1355 1938
> 27 1348 1937
> 28 1348 1945
> 
> 29 1355 1939
> 30 1363 1945
> 31 1356 1933
> 32 1361 1941
> 
> 33 1347 1934
> 34 1348 1930
> 35 1340 1926
> 36 1341 1931
> 
> 37 1349 1927
> 38 1355 1943
> 39 1348 1939
> 40 1348 1925


 
Those numbers are very similar to mine. Out of your 10 sets, only 4 of the discharged cells were lower (2 were tied) and of the 10 break-in's, only 6 were lower than the rest. Some were lower by only 1 or 2 points so I wouldn't really worry about it too much. Your C9000's are just fine.


----------



## uk_caver

I'd wonder how accurately components in the C9000 measurement chain were specified?
Much better than 1%?

Even +/- 0.5% would give +/-10mAh on ~2000mAh


----------



## hagbard

A bit of an update. Took four virgin AAA Duracell slow discharge batteries (800mAh), fully discharged them, then ran break-in. First slot came in at 779mAh as did the forth. Third was 781mAh and second was 789mAh. 

Then decided to put them back in on Charge, first slot worked fine, when I went to the second, the charger shut down. Tried again, it shut down again. Tried a third time and it worked. Continued with three and four.


----------



## vali

uk_caver said:


> I'd wonder how accurately components in the C9000 measurement chain were specified?
> Much better than 1%?
> 
> Even +/- 0.5% would give +/-10mAh on ~2000mAh



I reckon there can be a difference of about 50-100 mAh at max according lots of tests on eneloops that are posted in the forums. Some got around 1950 mAh whereas another ones got a bit over 2000+.

Those tests seem consistent for each charger and differs from others readings in a more or less constant quantity between charger samples.

Of course, all of this is just speculation.


----------



## arjay

fishinfool said:


> Those numbers are very similar to mine. Out of your 10 sets, only 4 of the discharged cells were lower (2 were tied) and of the 10 break-in's, only 6 were lower than the rest. Some were lower by only 1 or 2 points so I wouldn't really worry about it too much. Your C9000's are just fine.



Hah! I might just be too picky then. :shakehead


----------



## FlashPilot

Please help.

I just got a new MH-C9000 and #1 slot always shows 120-200 mAh lower than the rest. Ive moved cells around (brand new eneloops) and it makes no difference to the outcome. Is there a way to adjust or tweak it or should I return it for a replacement?


----------



## uk_caver

Is that on charge or discharge?

If it's on charge but not discharge, it could be stopping charging early, or doing a proper charge but underreporting the charge that happened.

The test for that would be to charge the same cell in multiple slots and discharge it, doing the discharge test always in one fixed slot. If the discharge figures are similar, then the charges were similar even if they're reported differently.

Having realised that that was happening on my c9000 (now out of warranty), with slot 1 being about 5% down on the others, it's just something I'll bear in mind and check every now and again, since it's not really stopping me getting the data I most want.

If it was like that on a new charger, especially out by up to 10%, I'd be asking for a replacement, not just because it made a difference to the usability, but because it might indicate something that could get worse, and also as a way of giving feedback to the manufacturer.


----------



## noisebeam

What is appropriate and maximum reasonable time to leave eneloop and sanyo (non eneloop) battery on charger after DONE is achieved?

If you do .5C charges as habit, do you do .5 of labeled capacity or measured capacity from a BI cycle? I have some older batteries that with multiple BI measure ~1500mah, but are labeled as 2500mah.


----------



## Anders

Hello noisebeam.

Two hours is an appropriate time to leave any AA cell, with AAA it is better to shorten that time.


Anders


----------



## 45/70

noisebeam said:


> What is appropriate and maximum reasonable time to leave eneloop and sanyo (non eneloop) battery on charger after DONE is achieved?



2 hours. After that the charger will drop the currentfrom 100mA to, I believe 10mA.

As for your 0.5C question, it's pretty safe to use the labeled capacity of the cell, but you could go either way, really. I hate to be the bearer of bad news, but your 2500mAh cells are probably toast. Just the same, I'd charge them at 1300mA (~0.5C), although if they get really hot, then I'd drop the charge rate to ~1000mA. Those cells, as I said though, are probably a lost cause.

Dave


----------



## noisebeam

45/70 said:


> As for your 0.5C question, it's pretty safe to use the labeled capacity of the cell, but you could go either way, really. I hate to be the bearer of bad news, but your 2500mAh cells are probably toast. Just the same, I'd charge them at 1300mA (~0.5C), although if they get really hot, then I'd drop the charge rate to ~1000mA. Those cells, as I said though, are probably a lost cause.
> 
> Dave


Sure they are toast for high drain applications, but they still last 2mo. in my computer mice, etc. or I use them in mp3 player for airplane trips and they never run out and I charge them after trip. The have ICVs between 1.8-1.9.

I also did not provides exacts as I didn't have them at the time, these are the 'near dead' and low cells I still keep in rotation for non flashlight use:

rated BI 
2300 1270
2300 1240
2300 1550
2300 1570
1800 1450
1800 1500

I'm still going to use them until they provide no more practical use, just didn't know if I should charge at rated or actual. I've been doing rated.


----------



## noisebeam

45/70 said:


> 2 hours. After that the charger will drop the currentfrom 100mA to, I believe 10mA.


Is it OK for the cells to leave them in longer than 2hrs? Anders (post above) suggested otherwise. Will 10ma trickle be bad for another 12 or 24hrs? Does it depend at all if LSD or not?


----------



## 45/70

OK on the "near dead" cells, noisebeam. I just wanted to make sure you understood their probable condition.



noisebeam said:


> Is it OK for the cells to leave them in longer than 2hrs? Anders (post above) suggested otherwise. Will 10ma trickle be bad for another 12 or 24hrs? Does it depend at all if LSD or not?



It is not recommended to leave any NiMH cell on a "trickle" charge. Unlike NiCd cells, continued charging of NiMH cells is bad for them. A lot of this depends on the rate of the charge, the lower, the more acceptable. From some tests that SilverFox, and I believe others did as well, LSD cells seem to be particularly sensitive to this, loosing their LSD capabilities. So it's best to avoid trickle charging LSD at all.

All this said, GP states that they left a cell (AA?) on charge for one year at a 0.1C rate, and it suffered minimal damage. I don't think it was an LSD cell, and I forget the specifics, but I wonder how well the cell actually would perform under a medium or high current load. My guess, is not too well, as trickle charging NiMH cells promotes voltage depression (reduced performance under load). It may have worked well in a wall clock or something. :shrug: I, like you, keep a few under performing cells around for such use. Why use a good cell?

Dave


----------



## Mr Happy

noisebeam said:


> Is it OK for the cells to leave them in longer than 2hrs? Anders (post above) suggested otherwise. Will 10ma trickle be bad for another 12 or 24hrs? Does it depend at all if LSD or not?


If I charge cells on my C9000 I have no qualms at all about leaving them on the charger overnight or for a day or two. A 10 mA trickle is low enough to be fine. I wouldn't leave them on the charger for weeks at a time though.


----------



## TakeTheActive

noisebeam said:


> ...If you do .5C charges as habit, *do you do .5 of labeled capacity or measured capacity from a BI cycle?* I have some older batteries that with multiple BI measure ~1500mah, but are labeled as 2500mah.


I use the MEASURED Capacity.

If you think about it, that's how much of the chemicals are still working.


----------



## SilverFox

Hello Noisebeam,

There are many thoughts on this, but I choose to use 80% as a cut off. Some manufacturers use 60% during cycle testing.

Since cells labeled 2300 mAh come in at 2000 - 2100 mAh during testing, let's give them a break and go with 2000 mAh. 80% of 2000 = 1600. When the 2300 mAh cells drop below 1600 mAh, I suggest it is time to recycle them and move on. If you went with 60% you would have 60% of 2000 = 1200.

Your 1800 mAh cells usually start out at around 1650 mAh. 80% of 1650 = 1320, so those cells are still good to go.

The reason I use 80% is mostly because of charging. When a cell drops below 80% of initial capacity, it is prone to missed terminations. Missed terminations result in hot cells and accelerated wear. The manufacturers that are using 60% are using the standard charge of 0.1C for 16 hours, so they don't factor in missed terminations.

"Dead" cells still hold some charge, but their performance is unpredictable.

Tom


----------



## SilverFox

Hello Dave,

The GP test had to do with emergency lighting. The batteries in emergency lighting have to be able to make the light work for a certain period of time. I seem to remember something like 15 minutes, but I don't know for sure.

The GP test demonstrated that the emergency lighting NiMh battery packs would still meet the specification after a year of being charged at 0.1C.

Tom


----------



## SilverFox

Hello Mr Happy,

I fully support your position on charging with the C9000... except I have a safety rule that I don't charge unattended. This limits the amount of trickle charge I subject a cell to.

However, if you are going to trickle charge cells, the Maha chargers have very low trickle charge rates and would be good chargers to trickle charge on.

Tom


----------



## TakeTheActive

Anders said:


> ...*Two hours is an appropriate time to leave any AA cell, with AAA it is better to shorten that time*...





noisebeam said:


> Is it OK for the cells to leave them in longer than 2hrs? *Anders (post above) suggested otherwise*...


Take note that *Anders* differentiated between *AA (2000mAh)* and *AAA (800mAh)*.

Depending on the Charge Rate you select when charging AAAs (0.5-1.0C), you need to check them after DONE appears to see if the "*100mA for 2 hours TopOff*" (0.125C) causes them to overheat.

For AAs, they're usually not FULLY charged @ 1.47VDC and the "*100mA for 2 hours TopOff*" (0.05C) gently finishes the job.


----------



## noisebeam

TakeTheActive said:


> Take note that *Anders* differentiated between *AA (2000mAh)* and *AAA (800mAh)*.


I said he suggested. That meant he said two hour is appropriate for AA, which suggests that more may not be appropriate.

Anyway, good thoughts here. I think I will change to using .5 of measured capacity when charging.


----------



## hagbard

I'm really feed up with this charger!!!

Grabbed a bunch I charged last week, put them in an older Canon camera, and it told me to change batteries. Grabbed another set I charged, same thing! Now its too late to send it back. I'm pissed.


----------



## noisebeam

Maybe the camera is old. Maybe it doesn't like NiMH voltages.
Did the C9000 report how much the batteries had been charged?


----------



## hagbard

noisebeam said:


> Maybe the camera is old. Maybe it doesn't like NiMH voltages.
> Did the C9000 report how much the batteries had been charged?



It is old, worked a month ago, with rechargables. I'm now checking it in my daughters toy keyboard...I'll report back on how long it lasts (usually at least two weeks).


----------



## Mr Happy

hagbard said:


> I'm really feed up with this charger!!!
> 
> Grabbed a bunch I charged last week, put them in an older Canon camera, and it told me to change batteries. Grabbed another set I charged, same thing! Now its too late to send it back. I'm pissed.


How old is older? I have charged Eneloops on the C9000 and used them in a Canon A620 after months of storage without trouble.


----------



## pae77

hagbard said:


> I'm really feed up with this charger!!!
> 
> Grabbed a bunch I charged last week, put them in an older Canon camera, and it told me to change batteries. Grabbed another set I charged, same thing! Now its too late to send it back. I'm pissed.


A bunch of what??? 

If they are not LSD type NiMH batteries such as e.g., Eneloops, the batteries are probably no good and are no longer holding a charge. If so, that is not the chargers fault but rather the batteries. With some good LSD batteries you should have much better results.


----------



## hagbard

Sorry, I was caught up in the emotion when I posted. They were AA Duracell Eneloop equivalents. Eventually I took the true Eneloops out of my son's camera, charged them (regular charge at 1000mAh) and they worked. The others were new (and never used) and had gone through the break-in cycle last week. 

I've sort of regretted getting this charger from the get-go (see other posts of you want to know why), and now I don't have the option to return it. For the price I paid I could have bought 40AAs, slapped it in the cheap Sanyo charger I have, and tossed them when they go bad...I'd still be ahead. I was sold on the report that it could revive previously dead batteries, it doesn't, that they'd greatly enhance the battery's lifetime and provide power from longer periods...none has proven true thus far.



pae77 said:


> A bunch of what???
> 
> If they are not LSD type NiMH batteries such as e.g., Eneloops, the batteries are probably no good and are no longer holding a charge. If so, that is not the chargers fault but rather the batteries. With some good LSD batteries you should have much better results.





Mr Happy said:


> How old is older? I have charged Eneloops on the C9000 and used them in a Canon A620 after months of storage without trouble.


 
Canon A75, I've had it about five years.


----------



## Mr Happy

hagbard said:


> Sorry, I was caught up in the emotion when I posted. They were AA Duracell Eneloop equivalents. Eventually I took the true Eneloops out of my son's camera, charged them (regular charge at 1000mAh) and they worked. The others were new (and never used) and had gone through the break-in cycle last week.
> 
> I've sort of regretted getting this charger from the get-go (see other posts of you want to know why), and now I don't have the option to return it.


It's true that the C9000 is a charger for people who are really interested in their batteries. For everyday charging and use you certainly could be very happy with a simple Sanyo charger that comes in an Eneloop bundle.



> For the price I paid I could have bought 40AAs, slapped it in the cheap Sanyo charger I have, and tossed them when they go bad...I'd still be ahead.


I think the C9000 is about $50 US. I think I could get maybe 16-20 Eneloops for that if I found a deal somewhere.



> I was sold on the report that it could revive previously dead batteries, it doesn't,


That's true, it can't. Dead batteries are dead.



> that they'd greatly enhance the battery's lifetime


Yes, it can certainly do this.



> and provide power from longer periods...


No, I don't believe it can do that.



> none has proven true thus far.
> 
> Canon A75, I've had it about five years.


The C9000 is a very capable charger, but it can't work miracles. Perhaps you have been led to expect too much from it. 

Some earlier digital cameras were known to have problems with rechargeable batteries. There is no charger or battery that will fully solve problems with such cameras except perhaps the NiZn system from PowerGenix.


----------



## hagbard

Mr Happy said:


> I think the C9000 is about $50 US. I think I could get maybe 16-20 Eneloops for that if I found a deal somewhere.



Charger cost me $70cdn (that was after discount), Duracell "eneloop" cost $7cdn per 4, AAA or AA when on sale (which is often). Think that works out to 40 for $70cdn?




> The C9000 is a very capable charger, but it can't work miracles. Perhaps you have been led to expect too much from it.


Buyers remorse. I think I would have been much better off using the $70 to replenish batteries as needed. The advantages of the charged don't seem that great (for me, nonexistent, but how knows, maybe I'll get bored enough to learn how to properly use it to gain some minor advantage).



> Some earlier digital cameras were known to have problems with rechargeable batteries. There is no charger or battery that will fully solve problems with such cameras except perhaps the NiZn system from PowerGenix.


Never had a problem before...but its working fine now...maybe some batteries I failed to recharge before using got into the mix.


----------



## arjay

hagbard said:


> Buyers remorse. I think I would have been much better off using the $70 to replenish batteries as needed. The advantages of the charged don't seem that great (for me, nonexistent, but how knows, maybe I'll get bored enough to learn how to properly use it to gain some minor advantage)
> 
> I kinda feel the same way. I also hate that I have to leave my batteries in the charger for 2 hours after it says done to have it reach ~100%.


----------



## hagbard

arjay said:


> hagbard said:
> 
> 
> 
> Buyers remorse. I think I would have been much better off using the $70 to replenish batteries as needed. The advantages of the charged don't seem that great (for me, nonexistent, but how knows, maybe I'll get bored enough to learn how to properly use it to gain some minor advantage)
> 
> I kinda feel the same way. I also hate that I have to leave my batteries in the charger for 2 hours after it says done to have it reach ~100%.
> 
> 
> 
> 
> Hummm...is that the trick? I need to leave them in an extra two hours after they're done?
Click to expand...


----------



## tandem

hagbard said:


> Hummm...is that the trick? I need to leave them in an extra two hours after they're done?



The charger is designed to treat your cells carefully to get the maximum life out of them and has various features in that regard.

When it comes to charging, the C9000 doesn't attempt to shove the full load in at the user-selected rate, perhaps in an effort to protect users from themselves, or perhaps because they've determined the best approach. 

No matter what charge rate you select, a gentle "top off" charge with a 100ma current is applied for 2 hours after the DONE signal is displayed at the end of the program, after that time the charger goes into trickle charge mode at 10ma. This is true for CHARGE, REFRESH, BREAKIN and CYCLE programs - the charge (or final charge) in the program is followed by top off and trickle.

What happens isn't really a secret -- the manual hints at this:



> When the program for a slot is completed, DONE will displayed to
> the right of the bank number. With the exception of DISCHARGE
> mode, topoff charge and trickle charge (continuous) will be applied.



But it is true, the manual could be clearer on this point.

The details can be found within this thread, or in this feature summary done by a member.

Is the C9000 worth it? I think so if only for the detailed information you can get out of it and nothing else. It seems likely that until one has cycled a lot of cells over a great many cycles that the full value of the unit won't be appreciated. Chances are you'd need to use a cheap charger along side with a controlled group of cells to really tell if there is a difference. In the past like many folks I've done the cheap charger thing with heavily used cells and know the unhappy results of using that gear and with less knowledge. I've got a group of cells managed by the C9000 which are used heavily (often discharged fully and charged daily) and their capacity is holding up far longer than anything I'd ever seen before, so I have no doubts at all as to the long term benefit of the C9000 even if I can't accurately ascribe the better capacity longevity to the cells (eneloops) or the charger, my gut tells me it is a bit of both -- a good match.


----------



## SilverFox

Hello Hagbard,

No trick, its just the way the charger works. It is a 3 stage charger. The bulk charge goes first, followed by a top off charge, and then it drops back to a very small trickle charge. The top off charge runs for 2 hours.

NiMh chemistry will warm up at the end of the charge, and in an effort to reduce wear on the cells, Maha brings the cells to nearly full during the bulk charge, then, if time permits, the top off charge packs the last little bit of capacity in.

You can use the cells when DONE is displayed, or you can wait until the top off charge finishes by waiting an additional 2 hours after the bulk charge finishes. Your cells will have greater cycle life if you pull them at the end of the bulk charge, and they will run a little longer in an application if you incorporate the top off charge. 

Decisions, decisions, decisions...

Tom


----------



## TakeTheActive

arjay said:


> ...*I also hate that I have to leave my batteries in the charger for 2 hours after it says done to have it reach ~100%*.


You COULD have bought a La Crosse BC-900/9009 instead and *COOK* :devil: them from 1.47 to ~1.55VDC @ 0.5C (i.e. 1000mA for AAs). 



SilverFox said:


> ...NiMh chemistry will warm up at the end of the charge, and *in an effort to reduce wear on the cells, Maha brings the cells to nearly full during the bulk charge, then, if time permits, the top off charge packs the last little bit of capacity in*.
> 
> You can use the cells when DONE is displayed, or you can wait until the top off charge finishes by waiting an additional 2 hours after the bulk charge finishes. Your cells will have *greater cycle life* if you pull them at the end of the bulk charge, and they will *run a little longer* in an application if you incorporate the top off charge.
> 
> Decisions, decisions, decisions...



Choices, choices, choices...


----------



## pae77

I really don't understand all this negativity towards the C9000. I just love it. It is so easy to just pop in Eneloop AA cells and take them off a few hours after they are done with no button presses needed. What could be simpler.

I have many 3 year old Eneloops that have mostly been charged with the C9000 that are still going strong.

Being able to program the charge rate within a broad range is a really important feature, imo, and I no longer purchase chargers that lack this capability.

I guess some people are just better off not using rechargeable batteries at all as the slight extra effort involved in learning about and caring for rechargeables (not to mention the different requirements for different battery chemistries) apparently is too difficult or not worth the effort for some.

For me it is part of the fun of being into flashlights. I think I enjoy the charging part of it at least as much as I enjoy using the lights.


----------



## tandem

pae77 said:


> For me it is part of the fun of being into flashlights. I think I enjoy the charging part of it at least as much as I enjoy using the lights.



I dub thee Battery Geek!

(guilty here too)

Mostly my desire to use rechargeable cells comes from being a thrifty sort who is also driven by ecological concerns. When NiMH became a viable alternative to NiCd I was all over them. Cells as well as lights and other devices have become so good at using power from AA and AAA sources... what a difference as compared to 10 - 20 years ago.

No doubt that for some an information-less charger is good enough, but I've always hated the lack of feed back that the typical charger provides with its 'green means done' LED feedback. When a cell reports as being finished charging quickly (or seems to go on forever) I like to get some feedback so I know if it simply wasn't depleted, or has been murdered.


(ps for Canadian readers, Sunday and Monday "duraloops" are back on sale at Shoppers Drug Mart for $6.99 a four pack)


----------



## Battery Guy

hagbard said:


> I've sort of regretted getting this charger from the get-go (see other posts of you want to know why), and now I don't have the option to return it. For the price I paid I could have bought 40AAs, slapped it in the cheap Sanyo charger I have, and tossed them when they go bad...I'd still be ahead. I was sold on the report that it could revive previously dead batteries, it doesn't, that they'd greatly enhance the battery's lifetime and provide power from longer periods...none has proven true thus far.



If you are a "set it and forget it" kind of person, then the C9000 is probably a waste of money for you. I think that, in general, a bunch of Eneloops paired with the Eneloop charger is a fine choice for most people.

Where the C9000 comes in handy is when you applications that require a large number of cells in series or parallel. In these applications, a single "dud" cell can impact the performance of the entire battery pack. Often it can be very difficult to figure out which cell is the dud. In these situations, the C9000 can be invaluable. It can also be very helpful for matching older cells with similar capacities for a given application.

With respect to reviving dead cells, the C9000 can erase the "memory effect", and it can also increase the capacity of cells that have been left dormant for a long period of time. However, there are plenty of chemical degradation mechanisms that are not reversible, and the C9000 can do nothing to help cells that have succumbed to them.

For the record, I LOVE my C9000!

Cheers,
BG


----------



## LA OZ

I thought it is time to give this charger a try as it was on sale and is on the cheap. I have just bought 2 C9000 so that I can do the testing in shorter time with all the batteries I have got lying around.

Prior to that I was wondering why wasting all those time and electricity trying to revive your cells. It would be cheaper to buy a new set of cells. Time is money.


----------



## 45/70

LA OZ said:


> Prior to that I was wondering why wasting all those time and electricity trying to revive your cells. It would be cheaper to buy a new set of cells. Time is money.



Unfortunately, I've found this to be true, in most cases. The C9000 excels at keeping new/good cells in good condition and extending their cycle life and performance, rather than restoring cells in poor condition. Still, they're worth it to me, and I am very happy with them (3 of them, that is ).

Dave


----------



## hagbard

Been wondering, I'm I better off fully discharging these Eneloop type batteries before recharging? Or going with a bit of charge left?


----------



## 45/70

hagbard said:


> Been wondering, I'm I better off fully discharging these Eneloop type batteries before recharging? Or going with a bit of charge left?



Unlike NiCd cells, it's best not to fully discharge NiMH cells every time they are used. The shallower the discharge, the more cycles you will get out of them. This takes into consideration that charging a cell from 50% twice, is the equivalent of one charge cycle. As long as the cells are basically discharged once in a while (this can be accomplished with a "BREAK-IN" on the C9000), to keep the chemicals well mixed within the cell, they will last longer this way. Also, keep in mind that a discharged NiMH cell means that it's voltage, when not under load, is ~1.20 Volts, not zero!

Dave


----------



## Tuikku

I forgot my radio-heaphones on over 3 weeks...
Eneloops were quite dry. Looking forward to see how they perform as cycles go by...


----------



## Turbo DV8

pae77 said:


> It is so easy to just pop in Eneloop AA cells and take them off a few hours after they are done with no button presses needed. What could be simpler.


 
Maybe nothing simpler, but clearer would be nice. If you are charging cells from various states of charge, there is no way to know how done is "done" for each cell. With all the talk of the importance of using cells of balanced charge and capacity, if you approach the charger and all cells say "Done," short of setting up camp next to the charger and taking notes like Jane Goodall, you've no idea when each cell has finished it's 100 mA, 2 hour top-off charge. Specifically, when it says "Done" it would be nice to have the time display count down to zero from 120 minutes. Otherwise, you could be pulling one cell holding, say, 2000 mAh, and the other only 1800 mAh, but they both say "Done." That's a 10% difference, hardly what most here would consider "balanced" charge.


----------



## 45/70

I'm with you on those points, Turbo. That is why, unless I watch the C9000 closely, I often pull the cells at some point after "DONE", let them rest a bit, and then top them off in the BC-900, when using cells in series applications. Alternatively, you can just make sure the cells have charged for _at least_ two hours after "DONE". Then you know that they are evenly charged.

The two hour top off, and the 2000mA pulse rate on AAA cells, are my only complaints about the C9000 though. It is still about the best AA charger out there and the analyzer features are a big plus.

Dave


----------



## SilverFox

Hello Turbo DV8,

A quick glance at the cells voltage will tell you if the top off charge is still in progress.

Tom


----------



## Turbo DV8

SilverFox said:


> Hello Turbo DV8,
> 
> A quick glance at the cells voltage will tell you if the top off charge is still in progress.
> 
> Tom


 
Hi,

That suggestion brings up another point which does really grate on my nerves every time I use the C9000, which is the order it sequences through the displayed information. Maha buried the displayed voltage as, what, the third piece of info presented? In my mind, voltage is THE most germane piece of information to know about a cells charging status, not "current in" or "time." It's a battery charger, Maha, not a kitchen timer. Maha should have made voltage the very first displayed value. To check the voltages of four cells requires a hell of a lot of waiting for each cell to cycle to the voltage, then move on to the next cell, and wait some more, and so on.


----------



## SilverFox

Hello Turbo DV8,

In my mind the charge or discharge time is the most important piece of information...  Fortunately, I am able to get that information 2 seconds before you get the voltage information. 

All in all it is a great charger, but I think they should have the option to hook up a monitor to it that displays a graph of voltage versus time or something like that. Of course the monitor would most likely cost more than the charger, and the interface would drive the price of the charger up as well.

Oh well, when I want all of that information I use my Schulze.

Tom


----------



## hagbard

45/70 said:


> Unlike NiCd cells, it's best not to fully discharge NiMH cells every time they are used. The shallower the discharge, the more cycles you will get out of them. This takes into consideration that charging a cell from 50% twice, is the equivalent of one charge cycle. As long as the cells are basically discharged once in a while (this can be accomplished with a "BREAK-IN" on the C9000), to keep the chemicals well mixed within the cell, they will last longer this way. Also, keep in mind that a discharged NiMH cell means that it's voltage, when not under load, is ~1.20 Volts, not zero!
> 
> Dave



Okay. Now, should I break-in new batteries before using or just charge them up first? Seems like Beak-in might be damaging.


----------



## SilverFox

Hello Hagbard,

I use this procedure with new cells.

I first discharge them using 500 mA for AA cells and 200 mA for AAA cells. 

Then I use the Break-In function.

Then I use the cells and charge normally.

Every 20 - 50 charge/discharge cycles I repeat the initial cycle of discharge and Break-In again.

If you have more cells than you can use and want to store some of them, discharge them, then every 30 days subject them to a charge/discharge cycle.

Eneloop and other low self discharge cells are an exception to this. I still do the initial discharge and Break-In, but you can stretch out the 30 day cycle to 6 months, and it appears that you can store them fully charged. I prefer to store them at about 80%, but have not had any issues with some that I have stored at 100%.

Tom


----------



## 45/70

hagbard said:


> Okay. Now, should I break-in new batteries before using or just charge them up first? Seems like Beak-in might be damaging.



With LSD cells, you can pretty much go either way. I do as Tom said above, only my initial discharge is at 100mA for either AA, or AAA cells. I feel that as the cells have usually been stored for a while, before I purchased them, it doesn't hurt to give them a slow discharge first.

As for "standard" NiMH cells, it's highly recommended to always do a discharge and a break in with new cells, and then repeat every 2-3 months. The exception to this, is if the cells are routinely discharged in service, every few weeks or so, then it is not necessary to do a break in quite as often. The cells (standard NiMH) will however, benefit from running a break in a couple times a year, even if used regularly.

Dave


----------



## hagbard

Well, there is definitely something not right about my charger. Just now I tried putting two AAAs in (Eneloop type). Put one in, set it to 400mAh, put the second in it shuts down. Swap slots, same thing. Tried different slots, same thing. Starts making a sparking sound...not good. These are also nearly brand new batteries. 

Okay, just tried another AAA in slot four, said HIGH. Its not the battery its the charger!

Time to give it a review on Newegg, unfortunately, not a positive one.

What especially annoys me is I have to ship it back to the States if I want a replacement, which often involves brokerage fees ($20-$50). Just isn't worth it. For the first 30 days I could have shipped it back to Newegg, too late. In the trash it goes.


----------



## Mr Happy

It has a warranty. If you think it's faulty, why don't you contact Maha?


----------



## hagbard

Mr Happy said:


> It has a warranty. If you think it's faulty, why don't you contact Maha?



Hi Happy, I have. Haven't heard back, but for the reasons I stated, I'd be unlikely to return it.


----------



## 45/70

hagbard said:


> Hi Happy, I have. Haven't heard back, but for the reasons I stated, I'd be unlikely to return it.



I don't know how it will work for you, but if you live in the States, they send you a new unit with a prepaid label for returning the defective unit.

Dave


----------



## hagbard

45/70 said:


> I don't know how it will work for you, but if you live in the States, they send you a new unit with a prepaid label for returning the defective unit.
> 
> Dave



I've heard back. Apparently they will send me a new unit, but it sounds like I won't be required to send the old one back (though I could be misreading). Logitech is the only other company I know that does that....pretty impressive. :twothumbs Still a bit concerned about brokerage though but I'll know that when it arrives (if they send it post or express, there won't be any, the risk is only for ground).


----------



## Notsure Fire

That's customer service.


----------



## hagbard

Notsure Fire said:


> That's customer service.



Yep, I'm pretty impressed, though I sent him the info he asked for and haven't heard anything back. Should I expect a reply or they'll just send it?


----------



## noisebeam

I'm surprised they don't want the old one back postage paid. At minimum I'd think they would want to check it out to help improve their quality.


----------



## jakeekaj18

I have a few questions if someone don't mind answering.

1. I have been charging my AA Batteries at 1000 mAh. Is this a good rate?

2. When using the Refresh & Analyse mode I use 500 mAh. Is this a good rate?

3. If I'm in a hurry can I use my C9000 as a 15 minute charger? I know charging the batteries too fast is not good for them, but lets say I'm in hurry and don't mind doing once in a great while. If so, what rate should I charge them at?


----------



## hagbard

noisebeam said:


> I'm surprised they don't want the old one back postage paid. At minimum I'd think they would want to check it out to help improve their quality.



"I am not requesting you to send the unit back to me." Could be cross border issues.


----------



## SilverFox

Hello Jakeekaj18,

Welcome to CPF.

The recommended charging rate for NiMh cells is 0.5 - 1.0C. If your cells have 2000 mAh of capacity, 0.5C would be charging at 1000 mA. If you are using the Maha C9000, the default charge rate is 1000 mA and that is good for all AA cells, even those that have a little more capacity.

When using Refresh and Analyze the default charging rate of 1000 mA and discharge rate of 500 mA is good for AA cells.

The maximum charge rate for the C9000 is 2000 mA. This won't charge your cells in 15 minutes, but it is fine to charge at that rate as long as your cells have a capacity of 1000 mAh or higher.

Tom


----------



## jacknife

Lets say we just got the C9000 .. Can anyone put the simplest way to use and charge your batteries when you first get this charger ,,.. So that we may use it Now.... and then learn buy reading the manual and gaining confidence??


----------



## tandem

jakeekaj18 said:


> If I'm in a hurry can I use my C9000 as a 15 minute charger?



As Silverfox said, no, it won't charge that fast and that is a good thing.

There is a really practical solution for your 15 minute charging desires that doesn't involve sacrificing cell longevity at all... buy another set of cells so that you have charged spares on hand and don't feel compelled to abuse them. On sale they can be had quite inexpensively if you keep your eyes peeled. In Canada I bought a bunch of 4-packs Duracell labelled Sanyo Eneloops on Monday for 6.99 each. Costco in the U.S. apparently has them at reasonable prices. Check in CPF Marketplace in the Good Deals section for breaking alerts...


----------



## Mr Happy

jacknife said:


> Lets say we just got the C9000 .. Can anyone put the simplest way to use and charge your batteries when you first get this charger ,,.. So that we may use it Now.... and then learn buy reading the manual and gaining confidence??




Plug in the charger
Put the batteries in the slots
After a few moments the charger will start charging
Wait for each slot to say "DONE"


----------



## jacknife

THANKS well why is it ,,, That some, make this charger seem so complicated? To operate??


----------



## noisebeam

jacknife said:


> THANKS well why is it ,,, That some, make this charger seem so complicated? To operate??


some have their biases and are willing to type more keystrokes expressing them than they would while operating a maha C9000


----------



## Turbo DV8

jacknife said:


> THANKS well why is it ,,, That some, make this charger seem so complicated? To operate??


 
Because if one wants to use settings other than the default rates, there are a quite a few more key strokes. Not only does one have to change the settings, one has to change them for each cell individually, unlike the "other" charger.


----------



## TakeTheActive

*What's Wrong With Reading the Manual (and maybe a FAQ or two)?*





jacknife said:


> Lets say we just got the C9000 .. Can anyone put the simplest way to use and charge your batteries when you first get this charger ,,.. So that we may use it Now.... and then learn buy reading the manual and gaining confidence??


What's the problem with reading the (short) manual and possibly a CPF FAQ or two now? :thinking:
.



Mr Happy said:


> Plug in the charger
> Put the batteries in the slots
> After a few moments the charger will start charging
> Wait for each slot to say "DONE"


And, those '_vanilla_' instructions are for a new / VIBRANT 2000mAh AA NiMH cell. Charge a new / VIBRANT 800mAh AAA cell, or an old 2000mAh (or less) High Internal Resistance AA cell, at the 1000mA default setting and you'll cook it.
.



jacknife said:


> THANKS well why is it ,,, That some, make this charger seem so complicated? To operate??


You bought the best (currently) AA/AAA NiCD / NiMH charger on the market. It is VERY flexible and has MANY settings. To accept the DEFAULT is like buying an expensive camera with MANY settings and operating it at ONE f stop and ONE shutter speed for all light / action conditions. The choice is yours...


----------



## TakeTheActive

Turbo DV8 said:


> ...Not only does one have to change the settings, one has to change them for each cell individually, *unlike the "other" charger*.


The La Crosse series of SMART chargers (BC-700/900/9009) have their own, unique '_CONs / negatives_' too.


----------



## pae77

And some might see being able to set the charge parameters for each bay individually as an advantageous feature rather than a negative . . . I know I do.


----------



## tandem

Ditto. I never have to organize my charging activity around what type of cell I need to charge, I can do multiple different types at once, and charge them all at a rate that is appropriate for them. It isn't uncommon at all to have three different types of cells occupying the four slots of my C9000, requiring three different charging rates.

(Not uncommon scenario: 1 Imedion AA 2400 mAh cell, 2 Eneloop AA 2000 mAh cell, and a 800 mAh AAA for good measure)

Being able to charge them all in one go, at rates appropriate for each, is a *real time saver*.


----------



## Turbo DV8

pae77 said:


> And some might see being able to set the charge parameters for each bay individually as an advantageous feature rather than a negative . . . I know I do.


 
The LaCrosse's rates can be set individually, or, all at once at any of the "given" rates. But 'tis true the LaCrosse has it's own bag o' worms, especially if you desire a rate other than what LaCrosse allows. It just would have been a very nice touch if Maha had provided the convenience of being able to select _any_ desired charge rate for all cells at once, _if_ so desired.


----------



## jakeekaj18

I just got a new pack of 4 Duracell (2650 mAh, I think) rechargeable batteries from CVS. I put them in the charger and put them on the Refresh & Analyse mode and put 500 mAh charge and discharge rate.

Two of the batteries are on discharge mode now and the other two are still charging. The two that are still charging have reached 4000 mAh and are still going (currently at 4026 mAh and 4022 mAh)

Isn't this WAY over what they should be? Did I do something wrong? They are getting pretty hot too, should I disconnect them?

http://www.youtube.com/watch?v=jur3BQB8qsA


----------



## Meku

jakeekaj18 said:


> I just got a new pack of 4 Duracell (2650 mAh, I think) rechargeable batteries from CVS. I put them in the charger and put them on the Refresh & Analyse mode and put 500 mAh charge and discharge rate.
> 
> Two of the batteries are on discharge mode now and the other two are still charging. The two that are still charging have reached 4000 mAh and are still going (currently at 4026 mAh and 4022 mAh)
> 
> Isn't this WAY over what they should be? Did I do something wrong? They are getting pretty hot too, should I disconnect them?
> 
> http://www.youtube.com/watch?v=jur3BQB8qsA



I'm just a noob with batteries but shouldn't the charge rate be 0.33C (minimum) which in this case would be 900 mAh?


----------



## SilverFox

Hello Jakeekaj18,

Your cells have not generated an end of charge termination signal. I believe the charge should time out at around 4500 mAh, or something close to that.

Your video shows that the voltage of the cells is 1.42 volts. This indicates that no -dV signal was generated, and the voltage of the cell did not increase to the 1.47 volt termination. Charging at a low rate does not produce a strong -dV signal, so next time use a charge rate in the 0.5 - 1.0 C range. The cells may have been stored for an extended period of time and that may be influencing the low voltage response.

Your cells are not behaving normally.

The fact that they are heating up is also a concern.

I would suggest that you discharge the cells, then run a Break-In function. If your capacity at the end of this step is 2400 mAh or higher, you just need to exercise the cells to get them back into shape. 

New cells are difficult to charge. Stale cells are difficult to charge. Crap cells are difficult to charge. In all of these cases, a 0.1C charge for 16 hours is probably the best method of charging. This is a timed charge that does not rely upon the cells response for termination, and it is charging at a rate that does not cause the cell to heat up.

Run a Break-In cycle and let us know what you end up with.

Tom


----------



## TakeTheActive

jakeekaj18 said:


> I just got a *new pack of 4 Duracell (2650 mAh*... ...I put them in the charger and put them on the *Refresh & Analyse mode and put 500 mAh charge and discharge rate*.
> 
> Two of the batteries are on discharge mode now and the other two are still charging. *The two that are still charging have reached 4000 mAh and are still going (currently at 4026 mAh and 4022 mAh)*
> 
> Isn't this WAY over what they should be? Did I do something wrong? *They are getting pretty hot too*, should I disconnect them?


I'm curious as to what the *Internal Resistance* is on these 'new' cells. I don't believe that ~0.19C (500mA) for ~8 hours should cause them to overheat. Also, as has been stated here on CPF MANY times before, one person's definition of hot can be wildly different from another's - and both can be below what's damaging to the cell. A thermometer is the best - I use the outdoor probe of an old RadioShack digital thermometer; others use thermal 'spot' thermometers.

Please post their *Impedance Check Voltages* (CLICK on my Sig Line LINK for instructions and interpretation).

Thanks!


----------



## pobox1475

I know 9000 will charge Ni-Cd cells. Is it advisable to run a Break-In or Refresh on new 1200 AA's? Had to get a few for outdoor lights that seem to not accept Ni-Mh per online research.


----------



## 45/70

I would. It certainly isn't going to hurt anything. The cells may have been in storage for a while and NiCd's are better cycled more often than NiMH cells anyway. On the other hand, use in a solar light is going to accomplish the same thing, really. The cells will be pretty much totally discharged and charged every day, sometihng that is not so good for NiMH cells. This is part of the reason NiCd's are preffered for such use.

As for charging with the C9000, all the same rules apply. But then I'm pretty sure you already knew that.

Dave


----------



## hagbard

Hey guys. Got the replacement charger this afternoon, put in some AAs to Charge as a basic test to see if it works. More oddness. Even though its Done, the time tells me 10 minutes even though its been over an hour since done...no updates on the minutes, said 10 minutes 30 minutes ago, 15 minutes ago, etc.


----------



## Mr Happy

hagbard said:


> Hey guys. Got the replacement charger this afternoon, put in some AAs to Charge as a basic test to see if it works. More oddness. Even though its Done, the time tells me 10 minutes even though its been over an hour since done...no updates on the minutes, said 10 minutes 30 minutes ago, 15 minutes ago, etc.


The indicated time is the charging duration, so it would be 10 minutes from the time you started charging until Done appeared. Once Done has appeared the information in each channel is frozen at the end of charge values, except for the voltage which continues to show the live value.


----------



## hagbard

Mr Happy said:


> The indicated time is the charging duration, so it would be 10 minutes from the time you started charging until Done appeared. Once Done has appeared the information in each channel is frozen at the end of charge values, except for the voltage which continues to show the live value.



You'd think I would have noticed that before. :thinking: Might just be too smart for me. :tinfoil:


----------



## uk_caver

[deleted]


----------



## njet212

Can we use C9000 to discharge alkaline or primary lithium aa to see it's actual capacity? Also what is cycle mode on C9000 function?

Some of my friend said if you not going to use your battery (Nicad dan Nimh) for extended period ( 1 month + ) it is better to completely discharged the battery before store it. Is it true?


----------



## Mr Happy

njet212 said:


> Can we use C9000 to discharge alkaline or primary lithium aa to see it's actual capacity? Also what is cycle mode on C9000 function?


Yes you can use the C9000 to measure the discharge capacity of alkaline or lithium cells. However, alkaline cells do not deliver their full capacity when discharged non-stop so you will not get the most accurate result. You can probably get a more accurate indication of capacity by looking at a manufacturer data sheet where they will have discharge curves for different kinds of load.

The cycle mode applies a programmed number of charge/discharge cycles one after the other.



> Some of my friend said if you not going to use your battery (Nicad dan Nimh) for extended period ( 1 month + ) it is better to completely discharged the battery before store it. Is it true?


This can be true for traditional rechargeable batteries, but it does not seem to be very important for the new breed of low self-discharge NiMH cell.


----------



## njet212

Mr Happy, thanks for fast reply 

Actually the alkaline battery i want to test is ABC Alkaline ( local brand battery ) where i can't found the data sheet on it's web.

So for LSD ( mine is old school Eneloop 1k cycles and Immedion LSD 2300 Mah ) are ok left for extended period without completely discharged them? even i left them fully charge using break-in mode ? or there is another treatment to do before store LSD for extended period?


----------



## 10.10.2010

​

Just finished using discharged mode for AA Alkaline on C9000. Results are 828 Mah for capacity and total time is 78 min, discharged @ 700 MaH.

Before discharged on c9000, i was try it on D11, could make the light on. After completed discharged at c9000 tried on D11 and it still make D11 on.

I'm wondering, does the discharged mode is only "test" the battery for it's actual capacity or it's completely discharged and depleted the battery?


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## Mr Happy

10.10.2010 said:


> Just finished using discharged mode for AA Alkaline on C9000. Results are 828 Mah for capacity and total time is 78 min, discharged @ 700 MaH.


See what I wrote above:



Mr Happy said:


> However, alkaline cells do not deliver their full capacity when discharged non-stop so you will not get the most accurate result.


You have just discovered how true this is. Another way of saying this is that you may get a completely inaccurate result.

However, if you discharge at 100 mA rather than 700 mA you may get a better indication of the true capacity.


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## Trancersteve

Can I ask how many other C9000 owners have a loud high frequency whining sound during the charging process?

I have owned my C9000 for a few years now and have been putting up with this annoying sound, but it has been annoying me so much lately that I have banished my C9000 to the spare room when charging.


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## noisebeam

All 'good' chargers I've had make the noise. Mine is in the laundry room.


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## Mr Happy

Luckily, when you get older your ears become less sensitive to high pitched whistling sounds and the C9000 is blissfully quiet


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## Trancersteve

Mr Happy said:


> Luckily, when you get older your ears become less sensitive to high pitched whistling sounds and the C9000 is blissfully quiet



I have heard this noise in quite a few devices but the C9000 takes the crown for being the loudest.

The funny thing is my hearing isn't that great to start with.

Well it is good to know that my C9000 is not unique with this annoying noise.


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## fishinfool

Mr Happy said:


> Luckily, when you get older your ears become less sensitive to high pitched whistling sounds and the C9000 is blissfully quiet


 
I have 2 c9000's and I haven't noticed any noise coming from them but the 'always on' bright led display bothers me at night though. So I guess that means that my hearing is shot.


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## Meku

fishinfool said:


> I have 2 c9000's and I haven't noticed any noise coming from them but the 'always on' bright led display bothers me at night though. So I guess that means that my hearing is shot.



My ears should be fine and I do hear the faint high pitch sound of c9000 but honestly it fades into all the background noise. If the sound is loud then there is good chance there is something wrong with the unit. 

If I want to know whats going on while charging I set up mine in the kitchen next to a fridge so the sound of the fridge covers the sound of the C9000. The only thing that I find bit odd is the "always on" back light of the screen. I really don't understand why there isn't a timer to turn it off.


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## fishinfool

Meku said:


> The only thing that I find bit odd is the "always on" back light of the screen. I really don't understand why there isn't a timer to turn it off.


 
Hopefully a backlight timer comes with the next generation of c9000's plus an on/off switch would be a nice addition also. :thumbsup:


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## Mr Happy

fishinfool said:


> I have 2 c9000's and I haven't noticed any noise coming from them but the 'always on' bright led display bothers me at night though. So I guess that means that my hearing is shot.


Maybe there is some variation between samples. With my C9000 I can hear it if I am close to it, but from a few feet away it is inaudible, much quieter than a ticking watch. I find the beep-beep-beep sound a convenient confirmation that it is working.

As for the backlight, I guess this depends on the kind of owner. For the younger person, whose bedroom is also their living space, I can see it being an issue. For others, who have studies or workshops to put their C9000 in, the backlight is not a problem.


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## fishinfool

Mr Happy said:


> I find the *beep-beep-beep sound* a convenient confirmation that it is working.


 
There's a beep-beep-beep-sound? Really? OMG, I must be going deaf!


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## Mr Happy

fishinfool said:


> There's a beep-beep-beep-sound? Really? OMG, I must be going deaf!


I've heard the newer ones are quieter than the earlier models. But yes indeed, the C9000 goes _beeeep-pause-beeeep-pause..._ when it's charging.


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## fishinfool

Mr Happy said:


> I've heard the newer ones are quieter than the earlier models. But yes indeed, the C9000 goes _beeeep-pause-beeeep-pause..._ when it's charging.


 
I bought my 1st last Dec. and the 2nd last Mar. so I guess mine are fairly new. I just now put some cells on to dicharge, then to charge just to see if it does make any kind of noise. I know, I know, get a life right? :laughing:


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## tandem

Mine is fairly new. It makes no sound at all. None.

(And for the record I like the nice backlight -- gives me something to navigate to in my office, as I tend to wander the house in the dark at night, even though my EDC light is in my pocket. Perhaps I do this in a vain attempt at trying to prove to myself that I'm not ageing as fast as I really am...)


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## bcwang

I can tell you that the newer ones don't make the noise anymore, I've seen 3 samples and all were rid of the whine.

I've had 4 samples of ones from a few years ago and they all had the annoying high pitched whine. I can understand why some couldn't hear it as the frequency is very high. I wouldn't call it a "beep" like some said, for me it is excruciatingly annoying. 

In fact, I recently was able to measure the older c9000 and the main whine occurs around 12.83 - 13.74 khz depending on which slot or combinations of slots are used. There were additional spikes at other frequencies higher and lower than that, but this spike was the loudest by quite a few decibels so would stand out the most. Those with loss of hearing in these frequencies would not be able to hear the whine.


----------



## Meku

bcwang said:


> I can tell you that the newer ones don't make the noise anymore, I've seen 3 samples and all were rid of the whine.
> 
> I've had 4 samples of ones from a few years ago and they all had the annoying high pitched whine. I can understand why some couldn't hear it as the frequency is very high. I wouldn't call it a "beep" like some said, for me it is excruciatingly annoying.
> 
> In fact, I recently was able to measure the older c9000 and the main whine occurs around 12.83 - 13.74 khz depending on which slot or combinations of slots are used. There were additional spikes at other frequencies higher and lower than that, but this spike was the loudest by quite a few decibels so would stand out the most. Those with loss of hearing in these frequencies would not be able to hear the whine.



Mine is very new (0j0fa) and it still makes the noise. Its very faint but its still there. Its hard to argue about high frequency noise...


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## csshih

Meku said:


> Mine is very new (0j0fa) and it still makes the noise. Its very faint but its still there. Its hard to argue about high frequency noise...



not if you have test equipment like the quoted poster had!

odd.. I have a 0j0ca, and I cannot detect any high freq. whine. -- and I am very good at detecting them, unfortunately... :sick2:


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## Meku

csshih said:


> not if you have test equipment like the quoted poster had!
> 
> odd.. I have a 0j0ca, and I cannot detect any high freq. whine. -- and I am very good at detecting them, unfortunately... :sick2:



In a way you're right but even then there the subjective differences. Then there are limitations of measurement equipment. Lets say microphone has high frequency response of 15-20 Khz. Most children and some adults can hear all the way to 20 Khz. Some will hear higher then 20 Khz. However, there are much variation in human hearing. Lets put it this way. Most should hear a sound around 12-13 Khz but only few adults will hear a sound of 20 Khz or higher. Therefore, some will think one unit is silent when other one will still hear it.

Regarding high frequency hearing; you either hear it or not. If you don't hear a frequency then you don't hear a sound at all. Its all or nothing here.


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## Notsure Fire

Good point. That's a logical way to put it.


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## Meku

If you want to test your high frequency hearing you can do it here. However, there is a VERY HIGH possibility that your soundcard won't support anything beyond 20 Khz and some don't go even beyond 15 Khz. There is good possibility that new MH-C9000 has very high frequency charge sound in a range of 17 Khz to 20 Khz so its silent to majority of users.


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## bcwang

Meku said:


> Mine is very new (0j0fa) and it still makes the noise. Its very faint but its still there. Its hard to argue about high frequency noise...



I tested an 0j0ca with one slot and there is a peak noise at a decently high 46db at 21.76khz. It tapers down to 26db by 20khz. So potentially you could be hearing it, and it would be even worse as this is a much higher frequency. This would explain why most don't hear it though, I think few adults, if any, have hearing above 20khz.


----------



## Meku

bcwang said:


> I tested an 0j0ca with one slot and there is a peak noise at a decently high 46db at 21.76khz. It tapers down to 26db by 20khz. So potentially you could be hearing it, and it would be even worse as this is a much higher frequency. This would explain why most don't hear it though, I think few adults, if any, have hearing above 20khz.



Sounds like Maha engineered the new units so that vast majority won't be bothered by the noise. 26 dB is not very loud but 46dB at 21.76 kHz could be very annoying indeed. Regarding hearing in general it is commonly stated that humans don't generally hear sounds higher then 20 kHz. Very very small number of adults can hear sounds over 20 kHz. Most adults can't hear a sound over 16 kHz. Normally middle age adults hearing tops at 12-14 kHz. Therefore, for vast majority new MH-C9000 is dead silent. For very few it can be heard and possibly to some "freak of nature" it can be very annoying. To get some perspective, security products like Mosquito which are designed to repel loitering teenagers use sound between 17 kHz to 20 kHz. Any adult hearing them should be happy since that would mean your ears are still in very good condition.

EDIT: Just out of general interest; are you using some high frequency measurement microphone? Must be if you can monitor sounds beyond 20 kHz...


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## thedeske

My unit's over a year old and quiet to my ears.
No dog around to test the upper range


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## pae77

I never noticed any sound coming from mine (about 2.5 years old). I definitely have diminished ability to hear some high frequencies though. :shakehead


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## Trancersteve

The trouble is that my hearing is quite shot to begin with due to loud prolonged headphone usage.

But I am 27.

I thought at around this age the ears start to lose the ability to hear these high frequency noises. But the C9000 sounds terrible and can sometimes be heard from the next room!

I am wondering if I can send it back to Maha even though I have had it for +3 years. Is it worth contacting Maha?


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## fishinfool

Trancersteve said:


> I am wondering if I can send it back to Maha even though I have had it for +3 years. *Is it worth contacting Maha?*


 
I would go ahead and contact them if I were you because who knows, they might surprise you. Plus you have nothing to lose except the time it takes to write the email. I'm very interested to see what they say. Keep us posted.


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## csshih

haha, OW!
guess my high freq hearing sucks.. I can only start hearing @ 17kHz..


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## bcwang

Meku said:


> EDIT: Just out of general interest; are you using some high frequency measurement microphone? Must be if you can monitor sounds beyond 20 kHz...



Surprisingly, it is an iphone app my friend has on his iphone 4. And if you have the 3gs or newer it is supposed to measure quite flat and samples at 48khz so up to 24khz sound can be detected. It's pretty awesome what you can do with an iphone these days.

http://www.faberacoustical.com/products/iphone/signalscope/


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## Meku

csshih said:


> haha, OW!
> guess my high freq hearing sucks.. I can only start hearing @ 17kHz..



Not necessarily. If you're in your teens then you can expect to hear frequences higher then 16kHz. Even then there is good chance you won't be hearing sounds as high as 20kHz. If you're an adult then hearing a 17kHz or higher is an excellent result. In reality high frequency hearing starts to go down at very early age. In general humans have best high frequency hearing at age of 8. For some reason males suffer more high frequency hear loss then females. 

Also there is a possibility that when testing high frequency hearing your system might start anti-aliasing the sound so there is chance that no sound comes out of your system at very high frequencies.


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## Meku

bcwang said:


> Surprisingly, it is an iphone app my friend has on his iphone 4. And if you have the 3gs or newer it is supposed to measure quite flat and samples at 48khz so up to 24khz sound can be detected. It's pretty awesome what you can do with an iphone these days.



With iPhone and such there is a "problem" of high frequency anti-aliasing. Set ups like these start to anti-aliase sound somewhere between 20 kHz and 24 kHz. Also you need to have high frequency measurement microphone to monitor high frequencies reliably. High frequency measurement microphones go to very high frequencies such as 150 kHz. Normal recording microphones top out at 20 kHz. After that they are not reliable. Since you managed to record 46db at 21.76khz it would suggest that there is a good chance 0j0ca MH-C9000 makes lot of noise at very high frequencies.


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## Turbo DV8

fishinfool said:


> I have 2 c9000's and I haven't noticed any noise coming from them but the 'always on' bright led display bothers me at night though. So I guess that means that my hearing is shot.


 
You need to look on the bright side of that. At least you know you're not blind!


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## fishinfool

Turbo DV8 said:


> You need to look on the bright side of that. At least you know you're not blind!


 
 That's funny Turbo!


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## csshih

Meku said:


> Not necessarily. If you're in your teens then you can expect to hear frequences higher then 16kHz. Even then there is good chance you won't be hearing sounds as high as 20kHz. If you're an adult then hearing a 17kHz or higher is an excellent result. In reality high frequency hearing starts to go down at very early age. In general humans have best high frequency hearing at age of 8. For some reason males suffer more high frequency hear loss then females.
> 
> Also there is a possibility that when testing high frequency hearing your system might start anti-aliasing the sound so there is chance that no sound comes out of your system at very high frequencies.



define, "teen". (I'm 18) when the final clock struck and I legally became an adult, did my eardrums relinquish their hold on higher frequencies? :nana:

I ran the test on a few systems and a cowon J3, using Etymotic ER-4Ss. :wave:


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## Meku

csshih said:


> define, "teen". (I'm 18) when the final clock struck and I legally became an adult, did my eardrums relinquish their hold on higher frequencies? :nana:
> 
> I ran the test on a few systems and a cowon J3, using Etymotic ER-4Ss. :wave:



 In scientific studies you are seen as an adult. Regarding the ability to hear high frequencies, your ability to hear them starts to diminish at age of 8. So statistically when you become 18 you should hear sound in 16 kHz range. Therefore your high frequency hearing is at least normal / above average. It is possible that in proper hearing test you could achieve slightly better results (it wouldn't be lower then 17 kHz).


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## vali

I can hear some whine too, but from the AC adapter and ONLY when there is no cells in the charger itself.

The noise appeared after some months of use.


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## hagbard

I hear a high pitched buzz too, but it isn't the charger. I have tinnitus and hear it all the time, day and night. Some might be starting to experience that.


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## Burgess

Yep !

Another sufferer of "constant ringing in the ears".

:wave:
_


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## bcwang

Meku said:


> With iPhone and such there is a "problem" of high frequency anti-aliasing. Set ups like these start to anti-aliase sound somewhere between 20 kHz and 24 kHz. Also you need to have high frequency measurement microphone to monitor high frequencies reliably. High frequency measurement microphones go to very high frequencies such as 150 kHz. Normal recording microphones top out at 20 kHz. After that they are not reliable. Since you managed to record 46db at 21.76khz it would suggest that there is a good chance 0j0ca MH-C9000 makes lot of noise at very high frequencies.



Not quite related, but I just wanted to mention I just measured a new lenovo laptop at work from a foot away and noticed a 21.87 khz sound at 95db! 95db! Those who can hear the new c9000 buzz will be completely driven crazy by what that laptop is outputting. I can't hear the sound, but after being in that room for half an hour, for some reason my ears are aching right now. Don't know if it's phantom or if it really did do something to my ears.


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## Black Rose

hagbard said:


> I hear a high pitched buzz too, but it isn't the charger. I have tinnitus and hear it all the time, day and night. Some might be starting to experience that.


I have it as well; it's really annoying. 

Background music as well as the noise from my wife's CPAP machine masks it enough so that I can sleep.


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## iamasmith

Hi, I have been using Uniross 2700 mAh cells for a couple of years now. I cycle 8 of them through a GPSr unit that I have and up to recently have been getting fairly decent performance out of them.

Sadly they seem to be dropping off a little and running out very quickly so I decided to look at something to recondition them and the other AA/AAA cells we use for various devices.

This thing looks the bees knees but one feature that didn't show up on any of the blurb was 'ramp up' that the C204W has. This feature I'm assuming is there to blow away 'micro shorts' as one review stated.

Does anybody know if this feature is built into the MHC9000, or is it even valid?

Cheers,

Andy


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## Mr Happy

iamasmith said:


> Hi, I have been using Uniross 2700 mAh cells for a couple of years now. I cycle 8 of them through a GPSr unit that I have and up to recently have been getting fairly decent performance out of them.
> 
> Sadly they seem to be dropping off a little and running out very quickly so I decided to look at something to recondition them and the other AA/AAA cells we use for various devices.
> 
> This thing looks the bees knees but one feature that didn't show up on any of the blurb was 'ramp up' that the C204W has. This feature I'm assuming is there to blow away 'micro shorts' as one review stated.
> 
> Does anybody know if this feature is built into the MHC9000, or is it even valid?
> 
> Cheers,
> 
> Andy


Hi,

NiMH cells have a finite service life, which for a regular kind of cell in constant use is about two years, give or take. They wear out due to gradual chemical and physical deterioration of the electrode materials and loss of electrolyte. In your case it sounds like your cells might simply be due for replacement. Remember they have already saved you a lot of money over alkaline batteries.

In some cases fading cells can be rejuvenated a bit, and the C9000 can do this, but it can't work miracles. The C9000 is a very good charger, however the best way to use it is to preserve and prolong the life of new cells rather than resurrecting dead ones.

Another good feature of the C9000 is it will tell you the true capacity of your cells. You might find your "2700 mAh" cells are nowhere near in reality, especially after some use. Some lower capacity cells like Eneloops start out with a bit less capacity but hold up for many more charge cycles. This would be a point to keep in mind when shopping for new batteries.


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## iamasmith

Cheers Mr. Happy,

I maybe misunderstood the best way of prolonging the life of the cells. Having 8 and cycling them means they have probably had only about 60 cycles or so each (if that) but yes, they are probably approaching 2 years old.

Sounds like it's best to stick with a smaller number of cells and keep them in constant service then.

Anyway, I'll see what happens with the MH-C9000.

Thanks again,

Andy


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## Mr Happy

iamasmith said:


> I maybe misunderstood the best way of prolonging the life of the cells. Having 8 and cycling them means they have probably had only about 60 cycles or so each (if that) but yes, they are probably approaching 2 years old.


This is generally fine, but the higher capacity cells like the 2700 mAh ones will sustain fewer cycles before they wear out. The only way to squeeze the higher capacity into those cells is to make the parts thinner, smaller and more fragile so that more can fit into the same volume. A rule of thumb is that 2700 mAh cells will tend to wear out after less than 100 cycles, whereas 2000 mAh cells might last for 200 cycles or more. The latest Eneloops are advertised to last for 1500 cycles, but those are special marketing department cycles and should not be taken as an indication of what you will actually achieve. It will however be way more than 60.


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## iamasmith

Thanks again! 

Anybody know for sure about that 'ramp up' feature I mentioned?


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## Mr Happy

iamasmith said:


> Anybody know for sure about that 'ramp up' feature I mentioned?


Applying carefully timed high current pulses before charging is not a generally recognized way to revive or recondition NiMH batteries. There was a possible reason for doing it to NiCd batteries but that reason does not apply to NiMH.


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## iamasmith

Picked one up today from Maplins and put the first batch of 4 on to Refresh and Analyse. It immediately showed up High on one so that has been discarded and we'll see what happens with the others. Nice unit!


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## iamasmith

One more question, sorry , when doing the Refresh and Analyse (which I note goes through steps Charge, Rest, Discharge, Rest Charge) as suggested from 1 to 3 times when attempting to rescue batteries is it recommended to intersperse the Refresh and Analyse stages with a Discharge stage in between or simply repeat them?

I assume the charger will on the 2nd and 3rd runs just check and top off then go into rest and then discharge, rest and charge so no harm done but I wanted to check that this was the way it was intended to be used.

Also, I'm assuming that if Break in is used on a cell then one should use Discharge before doing this (unless brand new and not pre charged)?


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## Mr Happy

iamasmith said:


> One more question, sorry , when doing the Refresh and Analyse (which I note goes through steps Charge, Rest, Discharge, Rest Charge) as suggested from 1 to 3 times when attempting to rescue batteries is it recommended to intersperse the Refresh and Analyse stages with a Discharge stage in between or simply repeat them?
> 
> I assume the charger will on the 2nd and 3rd runs just check and top off then go into rest and then discharge, rest and charge so no harm done but I wanted to check that this was the way it was intended to be used.
> 
> Also, I'm assuming that if Break in is used on a cell then one should use Discharge before doing this (unless brand new and not pre charged)?


With Refresh and Analyze the idea is to repeat until there is no further improvement. So if you do a Discharge after the Refresh has finished you can compare that reading to what the R&A reported. If the new discharge reading has increased it might be worth doing another R&A, otherwise not. If you have any plans on storing the cell rather than using it immediately, then discharging it is also a good idea, since traditional NiMH cells (not the new low self-discharge variety) last better if they are stored in a discharged state and cycled every six months or so.

As for the Break-In question, opinions vary. Many of us like to do a discharge first, but in theory it shouldn't make a lot of difference either way.

Also, when you run a Break-In you should set the capacity to what was measured by Refresh and Analyze, rather than the number printed on the cell.


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## iamasmith

Mr Happy said:


> ..
> Also, when you run a Break-In you should set the capacity to what was measured by Refresh and Analyze, rather than the number printed on the cell.



Thanks again, that sounds like it might be important but wasn't obvious from anything I read about the charger. I'm not really sure why you would lower the Break-In mAh setting, it doesn't seem obvious if you are trying to reactivate a cells full capacity and in any case Maha say that Break-In will attempt to slowly deliver 1.6 times the value entered for Break-In anyway.

Sorry for all the newbie questions btw


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## Mr Happy

iamasmith said:


> Thanks again, that sounds like it might be important but wasn't obvious from anything I read about the charger. I'm not really sure why you would lower the Break-In mAh setting, it doesn't seem obvious if you are trying to reactivate a cells full capacity and in any case Maha say that Break-In will attempt to slowly deliver 1.6 times the value entered for Break-In anyway.


You are right, it is not obvious. However, the Break-In cycle applies a measured and deliberate overcharge to the cell, which relies on the recycle reactions inside the cell being able to absorb and throw away the excess charge. If a cell happens to be somewhat worn out, then the ability to dissipate excess charge may be worn out as well. Therefore it is best to start gentle, and increase the charge rate if the cell can handle it. If the first Break-In cycle on the cell gives a higher capacity, then by all means use that capacity for the next Break-In.


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## iamasmith

2 out of the 5 so far tried (one showed High and was discarded immediately) seem OKish at about 83% capacity, they are doing their second R&A right now. 

The other 2 that are in the charger are doing discharge capacity readings of 1880mAh and 1788mAh (remember these started out as 2700mAh cells) 

Do you think it's worth trying to run a break in on these or just dump them? (I did pick up some Eneloops today also btw as a replacement)

Interestingly (and I think shockingly) the output current on the charger I HAD been using that came with these Uniross cells was a full 2.7A.... no wonder it charged them quick.. this could explain why they haven't survived all that long - that's going in the bin.


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## uk_caver

iamasmith said:


> The other 2 that are in the charger are doing discharge capacity readings of 1880mAh and 1788mAh (remember these started out as 2700mAh cells)


Remember they started out as _claimed_ 2700mAh cells, which doesn't necessarily mean they ever got anywhere near 2700mAh.
If you're getting 1800/1900mAh now, that might still be ~80% of actual original capacity.


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## iamasmith

Well, I have had success with 4 of the 8 original Uniross Performance 2700s and they have a good 80% of the capacity.

I've also got 4 Eneloop 1500s that have been through the process.

Finally, to see if it is viable I have taken the 3 very poorly performing Uniross 2700s which were down to about 1900mAh and having discharged them they are on a break in set to 1900mAh. 190mA for 16 hours is still 3040mAh, but at a bit more of a conservative rate so it will be interesting to see what happens.

Anybody really managed to recover cells performing so badly with this unit?

Cheers for the advice folks,

Andy


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## Mikl1984

*Maha AC Power Supply*

Maha name: MHS-CO1202000SS

Real Model: HAS02412U-AS produced by *WEIHAI POWER ELECTRONICS CO LTD*

I found this via UL database: E306708
http://database.ul.com/cgi-bin/XYV/...n=versionless&parent_id=1073992439&sequence=1


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## gopajti

*Re: Maha AC Power Supply*

Hi, this is the newest firmware -> *0K0AA*?


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## Mikl1984

*Re: Maha AC Power Supply*

It's just production batch
Your's made Jan 2011


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## jalyst

Meku said:


> If you want to test your high frequency hearing you can do it here. However, there is a VERY HIGH possibility that your soundcard won't support anything beyond 20 Khz and some don't go even beyond 15 Khz. There is good possibility that new MH-C9000 has very high frequency charge sound in a range of 17 Khz to 20 Khz so its silent to majority of users.



LOL, I wonder if dogs would be freaked-out by the noise?


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## Flashaholic_71

newbie.


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## jylam

I did a search to see if anyone else have this problem but cannot find anything...

I have 4 AAA Duraloops (800mAh, MIJ) that I used in the office for my wireless mouse (a pair at a time). They are charged with the older generation Duracell CEF14 charger whenever my mouse runs out of power and I use the 4 cells in pairs in rotation. I don't think they were charged/discharged for more than 50 to 60 cycles.

Recently, I found the batteries lasting less and less time. I decided to take them home to my MH-C9000 to refresh them. However, when I put them into the MH-C9000 and set to any of the charge cycle (charge, refresh, cycle or break-in), the charger would reset as soon as the cycle starts (the display turn dark and then light up again waiting for input as if I pulled out and reinsert the battery). This happens across all the slots and on all 4 AAAs. Only the discharge cycle would work but it shows "done" almost immediately for all 4 cells.

Two of the AAA's shows open voltage of 1.38V and the other two shows 1.19V with my voltmeter, if that helps.

Hoping it is not a charger problem, I tried some other AA and AAA Duraloops at home and I don't observe the same problem. The C9000 would go on with a charge cycle.

So... is it safe to say that the problem is NOT with my Maha charger? Also, is it time to toss the 4 AAAs from the office or is there other ways to "revive" them?

Thanks in advance for your help.


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## Mr Happy

Hi jylam,

When the C9000 does this it means the batteries have such a high internal resistance that the charger resets and will not try to charge them. This is an observed feature of the C9000, although it is only seen with batteries that are in very bad shape. You can tell from that that the problem lies with the batteries. Probably the CEF14 charger has ruined them by repeated overcharging. You do need to get some new batteries, but you should also charge them with a better battery charger. For a good life with AAA cells you should preferably find a charger that uses 500 mA on AAA cells and has smart termination. Your C9000 would seem to fit the bill. I recommend you charge your new batteries on the C9000 and dispose of the CEF14.


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## Wrend

Just got done reading both threads over the last few days in my spare time.

Do I get a cookie?

Glad to know all the quirks the C9000 has/had and to know mine is up to date and working as it should. Thanks for all of your contributions!

Looks like it'll do a good job of keeping my Eneloops healthy. Only slight reservation I had was thinking that it might overcharge the AAAs a little with the 2 hour 100mA top off charge. But, now it looks like that probably isn't the case? Has anyone compared a break in test followed by a second discharge, then normal charge (allowing for the top off charge to complete), and then another discharge to compare capacities? Haven't gotten around to it myself yet. I've been busy going through my new cells, breaking them in to test them and get them ready for service.

Before I got the C9000, I would individual charge, or series charge depleted cells in groups or packs of 2, 4, 5, 6, and 8 at a 0.1C/h rate for about 14 hours (which seemed to be long enough to charge and balance them). If they only made an 8 cell MH-C9000... Guss I'll probably end up picking up another one on my next order of cells (still need a few more so that I have enough on reserve).

The 1000mAh (0.5C/h) default charge rate is nice for AA Eneloops, but I wouldn't want to accidentally charge some older AAAs at that rate after a short power outage, if it can be avoided. Has anyone worked out a way to prevent this from happening? Basically, I'd like something similar to a fuse, only the opposite, that would trip when the power goes out, and that I'd manually have to reset after the power comes back on. I've shopped around a little and can't seem to find anything like this. I might end up building something if I can't find what I'm looking for, and for the fun of it. This time of year there are a lot of storms that go through the area, and I'm going to be breaking in cells for another month and a half at least.


----------



## uk_caver

Wrend said:


> Has anyone worked out a way to prevent this from happening? Basically, I'd like something similar to a fuse, only the opposite, that would trip when the power goes out, and that I'd manually have to reset after the power comes back on. I've shopped around a little and can't seem to find anything like this.



At least _some_ plug-in RCDs (GFIs) disconnect on supply removal and have to be manually primed before passing power again.


----------



## 45/70

Wrend said:


> Just got done reading both threads over the last few days in my spare time.
> 
> Do I get a cookie?



Yes, or you should anyway! I say this because if everyone did read through threads completely, before asking questions, they would often find that their question had already been answered previously. On the other hand, I can understand being reluctant to read through threads that are as extensive as this one, and quite a few others.:shrug:



> Only slight reservation I had was thinking that it might overcharge the AAAs a little with the 2 hour 100mA top off charge. But, now it looks like that probably isn't the case?


Many have come to the conclusion that the AAA eneloops are robust enough that they can absorb this slight overcharge. I myself try to pull the cells soon after "DONE", if I can. This way there is no doubt that any possible damage to the cells due to overcharging, will be avoided. That's just me though. I figure the slight tradeoff in lower obtained capacity vs. potentially longer cell life is worth it. If I forget and the cells do end up going through the 2 hour "top off", I don't sweat it, as I said, many think these cells can handle it.

One thing to consider, pound for pound, AAA cells compared to AA cells are at a disadvantage, due to their diminutive size. Regardless of the chemistry of the cells, the AA version is always going to last longer. It's a case where "bigger is better" when it comes to battery cells. When miniaturization is involved, there is frequently a bit of a tradeoff, take a laptop vs. a desktop computer for example. Anyway, I figure if I can help the AAA eneloops out a bit, I'll give it a shot.



> The 1000mAh (0.5C/h) default charge rate is nice for AA Eneloops, but I wouldn't want to accidentally charge some older AAAs at that rate after a short power outage, if it can be avoided. Has anyone worked out a way to prevent this from happening?


I simply run all of my chargers through a UPS, as I do my cordless phone. This won't help if the power is out for a really long time, but avoids most problems. The power consumed by the C9000 is minimal, so it works out for me most of the time.

I live in a rural area where the power company definitely puts us on the "back burner". The power goes out here on average once per day. Usually it's just a "blip", in which case a UPS has no problem backing up the charger(s). Once in a while, as happened just last week, a T-storm came through and the power was out for 6 hours. In this situation the UPS may not cover the situation, but I'm well aware that the power went out in such instances, and can take the necessary steps required to rectify the situation.

Dave


----------



## Wrend

Thanks for the recommendations, guys. 

It turns out that I actually have a nice 12V relay hanging around collecting dust anyway. I can hook that up with a momentary switch and use one of the relayed lines to power the relay itself and one of the other lines to power the charger. I'd have to put it in line after the wall wart AC adapter though, and it would only be good for one of the chargers.

So something like a GFI would work better still since I could use it for more than one charger. Unfortunately, I can't seem to find one locally here in the home improvement, big box, or other stores that will do.

A UPS might work too. Since the chargers run off of 12VDC, I might just get a deep cycle 120AH Pb battery to run them off of which is being maintained while the power is on. I'd need to find a nice maintenance/float charger for that though. That might be the way to go since I can use the Pb in some other applications too. I'm getting more into amateur radio and would like to have portable power off the grid in case of an emergency. As well as powering my other 12V portable chargers that I use for my RC batteries.

But, that's getting a little more expensive and isn't really a quick fix like I was hoping for.

Any troubles with powering the C9000 off of Pbs?

Cheers.


----------



## Russel

Wrend said:


> [...]Any troubles with powering the C9000 off of Pbs?[...]


 
I routinely operate my MH-C9000 off of a 12V car battery while it is being charged with a solar panel. The voltage varies from 12.5V to 14.2V without any detrimental effects to the charger.


----------



## Wrend

Good deal. Think I'll go that route then.

In the mean time I think I'll make something using that relay. Now to hunt down that project box with the momentary switch on it. Think I have a double color LED that I'll use to know the status of the relay at a glance.

Should be a fun afternoon project. I'll have to wait 'til around 00:30 tonight for the charger to be done with its current break in before I put some deans plugs in line on the AC adapter, though. I'll want to do that eventually anyway for connecting the charger to the Pb bus.

Happy charging. 

-Mick

Oh, also, I'll report back with those AAA capacity comparisons I was talking about to see how fully the top off charge charges them, and whether or not I think it's worth worrying about them being over charged. As it is, it is pretty close to a 0.1C/h rate anyway.


----------



## tallyram

Sorry if this has already been covered. 

My C9000 always stops charging slot 1 first. I have 24 eneloops and no matter which ones I'm charging slot 1 peaks first with around 100mah less than the others. Is this normal for this charger?


----------



## Wrend

Not that I know of. The ports on mine do seem to vary just a little from each other consistently, but it seems to be close to about 1% to 2% capacity.

Maybe the calibration of that port is a little off. If you're concerned about it, it might be worth it to send it in to be serviced or replaced.


----------



## tallyram

This C9000 is a replacement. I sent my original back for the same issue! Just had another batch of eneloops come off and slot 1 read about 100mah lower and stopped the charge 6 minutes sooner. I really don't want to pay shipping for another return. It seems like a nice charger, but how did I just happen to get 2 with the same problem? Wondering if this is just bad QC???? Going to email maha.


----------



## Wrend

Here are those AAA Eneloop test results on new cells. All were initially discharged at 100mA.

Break In (800mAh) Discharge 1: Cell 1 (808mAh), Cell 2 (821mAh), Cell 3 (809mAh), Cell 4 (816mAh); Average (813.5mAh)

100mA Discharge 1: Cell 1 (829mAh), Cell 2 (835mAh), Cell 3 (829mAh), Cell 4 (834mAh); Average (831.5mAh)

All cells were then charged at 0.5C/h (400mA) and allowed to "top off" charge for 2 hours, "trickle" charge for 1 hour, and then disconnected to rest for 1 hour.

100mA Discharge 2: Cell 1 (806mAh), Cell 2 (822mAh), Cell 3 (811mAh), Cell 4 (814mAh); Average (813.5mAh)

Break In (800mAh) Discharge 2: Cell 1 (809mAh), Cell 2 (818mAh), Cell 3 (809mAh), Cell 4 (817mAh); Average (813.25mAh)

Though it's far from proving anything conclusively, based on these numbers, I don't think allowing the Eneloop AAAs to go through the Top Off charge is significantly overcharging them. Also, keep in mind that the 100mA discharge capacity tests should have allowed for somewhat more capacity to discharge from the cells than the Break In 160mA discharge test results.

Though the MH-C9000 does not appear to be overcharging these cells with the Top Off charge, it may still be marginally beneficial for maximum battery cycle life to not top off charge these cells.

What I'm actually concerned a little more about now is the heat build up from the charger behind cells 2 and 3. I may install a thin metal strip along the flat area behind where the cells are placed and bend it down along the sides and a little behind the charger to help even out and radiate this heat away.


----------



## ltcdata

Hello everyone!
After 1 month of reading EVERYTHING i could about chargers, mostly here, a post from taketheactive on fatwallet, etc, i've finally decided on the maha MH-C9000 over the LaCrosse 9009.
I think the only things that i hate but i have to live with of the maha are the impossibility to set the four banks to the same setting at once, and only being able to see the status of 1 cell at the same time (the 4 displays in the 9009 could be perfect on the maha!).
But the lowest voltage of the trickle charge of the maha, the ability to better fine tune the charging of each cell (i have Sanyos 2700's, Eneloops, AA, AAA's, etc), the refresh functions, etc.. i think the maha is a better charger than the LaCrosse. Being me a technical guy i will buy it. I use the nimh batteries for Nikon flashes and flashlights mostly.
I live in argentina, so i expect 1 month minimum of delivery time.
I will post again when i receive it


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## Swedpat

Yesterday I received the MH-C9000 charger. I understand it's a great charger, but what advanced! I try to read the description but am not sure I get it. 
Any basic tip for Eneloop AAA/AA and 2500-2700mAh common batteries, about charging/discharging current? It is programmable but what is best? I know that lower current is better for the battery life, but too low isn't good either... What's the difference between the "C"-rates and mAh value? In this case I really feel me as a newbie and a dummy...


----------



## Anders

Hello Patrik.

There is no reason for us to over again explain what is written in this thread.
I did a review in this forum that you was using before:
http://www.utrustning.se/viewtopic.php?t=9279

You can also look at the first page in this thread and move on...


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## Swedpat

Anders said:


> Hello Patrik.
> 
> There is no reaso fpr us to over again explayn what is written in this thread.
> I did a review in this forum that you was using before:
> http://www.utrustning.se/viewtopic.php?t=9279
> 
> You can also look at the first page in this thread and move on...



Reading through 26 pages on english just feels too much. Forgot the login username and password to the swedish site. Well, I will see if I find it out...


----------



## Anders

I also did the same in this swedish site:
http://www.fotosidan.se/reviews/viewreviews.htm?ID=16501


----------



## Swedpat

Thank you Anders, it's always easier on it's own language. I will bookmark your review.
Did I understand it right that 1000mA with AA Eneloops at 2000mAh is 0,5C?


----------



## Anders

Yes it is Patrik.
Anders


----------



## Mr Happy

I always charge AA cells at the default 1000 mA, including 2700 mAh ones, unless I want a particularly fast charge when I will use higher. AAA cells I charge at 400 mA.

Discharging doesn't matter too much; I use 500 mA for AA and 200 mA for AAA.

There's no need to worry about C rates and stuff like that. It just over complicates a simple situation.


----------



## Swedpat

I just refreshed and analyzed 4 GP 2700mAh batteries. It shows DONE for all channels and I understand that does mean the process it's finished. These are the values for the four batteries:

1: 1827mA, 1,40V
2: 1854mA, 1,39V
3: 1630mA, 1,38V
4: 1733mA, 1,41V

What conclusion can I do of this result? The capacity seems to be low for 2700mAh cells. Thankful for some support, never used such an advanced charger before.


----------



## bbb74

If you picked refresh&analyse and about 10-14 hours later you have "DONE" on the screen then yep you're done. That's a very poor result  You could try it again to see if they improve (personally I'd do a discharge first). How old are the cells?


----------



## samgab

Swedpat. It means those cells don't really have a capacity of 2700mAh. I just recently got some brand new "2800" mAh Fujicell batteries, and they are all getting about 1800mAh results on break in whereas my eneloops are all getting more than 2000. You get what you pay for with battery cells in most cases.
I suggest you do a *break in* on those GP cells of yours and see what you end up with.
Please read this: http://www.mahaenergy.com/store/mhc9000faq.asp
Read it three or four times carefully, and if you still don't understand any aspects, come and ask further questions.


----------



## Swedpat

bbb74 said:


> If you picked refresh&analyse and about 10-14 hours later you have "DONE" on the screen then yep you're done. That's a very poor result  You could try it again to see if they improve (personally I'd do a discharge first). How old are the cells?


 
I don't know exactly, but I think I bought them for at least 3-4 years ago. I guess I can improve the performance with this charger!



samgab said:


> Swedpat. It means those cells don't really have a capacity of 2700mAh. I just recently got some brand new "2800" mAh Fujicell batteries, and they are all getting about 1800mAh results on break in whereas my eneloops are all getting more than 2000. You get what you pay for with battery cells in most cases.
> I suggest you do a *break in* on those GP cells of yours and see what you end up with.
> Please read this: http://www.mahaenergy.com/store/mhc9000faq.asp
> Read it three or four times carefully, and if you still don't understand any aspects, come and ask further questions.


 
Thanks for the link!

Now I see I likely didn't made it right first time, missed to adjust for all cells. Now I started the charger again at refreshing and analyzing, and adjusted the charge/discharge rates to 1300mA/700mA instead of 1000/500. Will see tomorrow the result.


----------



## Mr Happy

Swedpat said:


> Now I started the charger again at refreshing and analyzing, and adjusted the charge/discharge rates to 1300mA/700mA instead of 1000/500. Will see tomorrow the result.


No, this won't be any better. You should just stick with 1000 mA /500 mA (see my post above).

Your cells read low because they are old and under performing. This result is generally unsurprising. Many cells measure lower than what the label says. Such cells may improve by running repeated refresh/analyze cycles on them. They may improve some more by running a break-in cycle on them. However, if you run a break-in, set the capacity to what you measured here (1800 mAh), do not set the capacity to 2700 mAh.


----------



## Swedpat

Mr Happy said:


> No, this won't be any better. You should just stick with 1000 mA /500 mA (see my post above).
> 
> Your cells read low because they are old and under performing. This result is generally unsurprising. Many cells measure lower than what the label says. Such cells may improve by running repeated refresh/analyze cycles on them. They may improve some more by running a break-in cycle on them. However, if you run a break-in, set the capacity to what you measured here (1800 mAh), do not set the capacity to 2700 mAh.



I chosed 1300/700 because it's the advice by the manufacturer in the page *samgab* linked to. So you advice I stop the refreshing and analyzing and start again with break-in?


----------



## Mr Happy

Swedpat said:


> I chosed 1300/700 because it's the advice by the manufacturer in the page *samgab* linked to. So you advice I stop the refreshing and analyzing and start again with break-in?


There are lots of guidelines around, but to be honest many of these guidelines are not quite as rigid as you might think. My personal recommendation is that if you charge an AA cell at 1000 mA on the C9000 it will be fine.

As to your particular cells, what you may find is that repeating the refresh/analyze process may lead to improvements in capacity. If you do that, it helps to use the same settings each time so the results are not influenced by changing the settings.

If you find that repeated refresh/analyze is not giving an improvement, then is the time to do a break-in cycle. 

Given what I've said, you might want to stop the current refresh/analyze and restart it using the same settings you used the first time just for consistency.


----------



## Swedpat

Thanks Mr Happy for the response. I will think about it.


----------



## AlphaZen

I read through this entire thread over the last couple days and opened some of the more informative posts in tabs on my browser, with the intention of organizing the information somehow. I came up with a CPF Blog entry, mainly to try the feature, although none of the information is my own and I don't intend to "blog" about the posts. It was just a way to manage the information which is all culled from posts made in this thread, and in some instances from other related threads. I did change a few entries slightly just for clarification. Here it is. Tell me what you think. :shrug:


----------



## Swedpat

Because I was not really sure about what value of charge and discharge current the first refresh and analyze-round was made at all cells I let the second refresh and analyze round continue at 1300/700mA. 

First round:

1: 1827mAh, 1,40V
2: 1854mAh, 1,39V
3: 1630mAh, 1,38V
4: 1733mAh, 1,41V

Second round: 

1: 1810mAh, 1,39V
2: 1773mAh, 1,38V
3: 1668mAh, 1,37V
4: 1757mAh, 1,41V

After that I did a Break-in, with the final result:

1: 1845mAh, 1,41V
2: 1764mAh, 1,40V
3: 1699mAh, 1,39V
4: 1933mAh, 1,43V

*BUT*: during the Break-In process the mAh value of the cells reached up to around 2500mAh before the discharge began. 

Regards, Patric


----------



## Mr Happy

Swedpat said:


> *BUT*: during the Break-In process the mAh value of the cells reached up to around 2500mAh before the discharge began.


Yes, it is supposed to be this way. The break-in process applies a slow charge for a long fixed time to rejuvenate the cells. What capacity did you set for the break-in, 1800 mAh maybe?

It looks as if not much can be done to improve these cells. They are stuck around 1800 mAh and that is apparently all they have in them.


----------



## Swedpat

I think it was 1800. But what kind of difference that could make?

However, I understand I can draw that conclusion the batteries are not lost, but still not close to the capacity they should have.


----------



## samgab

Swedpat said:


> I think it was 1800. But what kind of difference that could make?
> 
> However, I understand I can draw that conclusion the batteries are not lost, but still not close to the capacity they should have.



Have you actually read the info about how the break-in program works?


----------



## Lightfoot98

Swedpat said:


> Because I was not really sure about what value of charge and discharge current the first refresh and analyze-round was made at all cells I let the second refresh and analyze round continue at 1300/700mA.
> 
> First round:
> 
> 1: 1827mAh, 1,40V
> 2: 1854mAh, 1,39V
> 3: 1630mAh, 1,38V
> 4: 1733mAh, 1,41V
> 
> Second round:
> 
> 1: 1810mAh, 1,39V
> 2: 1773mAh, 1,38V
> 3: 1668mAh, 1,37V
> 4: 1757mAh, 1,41V
> 
> After that I did a Break-in, with the final result:
> 
> 1: 1845mAh, 1,41V
> 2: 1764mAh, 1,40V
> 3: 1699mAh, 1,39V
> 4: 1933mAh, 1,43V
> 
> *BUT*: during the Break-In process the mAh value of the cells reached up to around 2500mAh before the discharge began.
> 
> Regards, Patric




Is that charge numbers or discharge??


----------



## Mr Happy

Swedpat said:


> I think it was 1800. But what kind of difference that could make?





Mr Happy said:


> However, if you run a break-in, set the capacity to what you measured here (1800 mAh), do not set the capacity to 2700 mAh.



A break-in cycle does a deliberate overcharge of the batteries. If the batteries have a real capacity of 1800 mAh and you set the break-in to 2700 mAh you will run the risk of doing more harm than good.


----------



## Swedpat

Lightfoot98 said:


> Is that charge numbers or discharge??


 
According to the manual at post 2 of this thread the values on the display after refresh-and-analyze and Break-in process are discharge capacity, so it must be discharge capacity.


----------



## bbb74

Swedpat said:


> It's the final values I could read on the display when the process was DONE. And as well fresh and analyze as Break-in finish with charge.
> 
> Now I read at the instructions on the first page of this thread: "_In the REFRESH & ANALYZE and BREAK-IN mode, the final capacity displayed is the discharging capacity. The battery have also been recharged after the discharge_."
> 
> This means the mAh values I mentioned are discharge?


You're thinking too much  The only way to know the actual capacity of a cell is to discharge it and count how many mAh came out of it. Its not like a jug of water where you can simply look to see how full it is, or a car with a fuel gauge. Its more like a jug of water that you can't see inside of - you can take a guess by how much sloshes around inside (or use the voltage of a cell) but it won't tell you exactly.



> Sorry for beeing such a novice here, never before used something like this. I just want to know how many mAh the cells contain after the charging is finished, don't even understand what does it then mean with disharging capacity...


The only way to find out exactly how many mAh the cells contain is to discharge them and count how many came out  There is no equivalent of a fuel gauge. The amount of mAh you put in during a charge is not the same amount that will come out. Lots of mAh will get wasted or lost during the charge.



> With such an advanced charger, I wish it also had a function for just inserting the cells and read the actual capacity in V and mAh, without doing some charge or discharge process.


As described above, no charger will give you the mAh capacity without discharging the cell. You can get a voltage reading by putting the cell in and selecting "discharge" at 500mA. Give it 10 seconds to rotate around to display the voltage and there you go. Pull it out. It will have discharge 0-1mAh which is nothing to do this. You then need to know how to interpret the cell's voltage to know roughly how much capacity is left in it.


----------



## Swedpat

Thanks for the GREAT explanation *bbb74*!

Though I felt me dumb and deleted the text you read it before I did it.

Again, thanks!


----------



## TakeTheActive

*Rechargeable Cells Newbies - Learning Curve / Language Barrier...*



Mr Happy said:


> ...The break-in process applies a slow charge for a long fixed time to rejuvenate the cells. *What capacity did you set for the break-in, 1800 mAh maybe?*
> 
> It looks as if not much can be done to improve these cells. They are stuck around 1800 mAh and that is apparently all they have in them.
> 
> 
> Swedpat said:
> 
> 
> 
> *I think it was 1800. But what kind of difference that could make?*
> 
> However, I understand I can draw that conclusion the batteries are not lost, but still not close to the capacity they should have.
Click to expand...

In many respects, a USED / *CRAP* cell with a PRINTED Capacity of 2700mAh but a MEASURED Capacity of 1800mAH is very similar to a NEW / VIBRANT cell with a PRINTED Capacity of 1800mAh and a MEASURED Capacity of 1800mAh. The 0.5C Charge Rate is 900mA for both; the 0.2C Discharge Rate is 360mA for both. Internal Resistance may be WAY different - thus, the NEW 1800mAh cell may be able to supply 1600-1700mAh at a 1800mA Discharge Rate, while the *CRAP* 2700mAh (with a current Capacity of 1800mAh) might only be able to supply 900-1000mAh at a 1800mA Discharge Rate. And, at this point, the cell may not be 'Dead' - just unable to meet the Discharge Rate demands. Drop the Discharge Rate down to 100mA, or less, and you may just get another 600mAh out of the *CRAP* cell.

When comparing NEW cells, different Charge and Discharge Rates don't matter 'too' much. But, as a cell ages, and Internal Resistance increases, discharging at 0.5C or higher will most certainly produce a lower Capacity than discharging at less than 0.5C, such as 0.1C. It's not very difficult to learn / understand how all of this works, but, it's best learned, IMHO, by SEARCHing and READing and not repeatedly asking questions that have been 'Asked-and-Answered' *MANY* times over the years.

Sorry about the language barrier - how does Google Translate work for you?


----------



## Swedpat

*Re: Rechargeable Cells Newbies - Learning Curve / Language Barrier...*



TakeTheActive said:


> Sorry about the language barrier - how does Google Translate work for you?


 
If you asked me I don't use Google for contributing this forum, only for translating from, for example, german, to english or swedish. In that case it actually works quite good, but makes some funny sentences...

Regards, Patric


----------



## Paul_in_Maryland

Last year, I posted a PDF of the scanned MAHA C-9000 user documentation. It's time I posted the link in this thread.


----------



## Swedpat

I just completed a refresh & analyze followed by a Break-in on 4 batteries. The batteries are of the brand VANSON and 2500 mAh. Number 1 and 2 I have been using together and also 3 and 4.

The refresh and analyze gave this result, I used the default charging and discharging rates:

1: 247mAh, 1,42V
2: 1649mAh, 1,44V
3: 1919mAh, 1,43V
4: 1869mAh, 1,43V


The Break in gave:

1: 1967mAh, 1,36V, 1278min Chosed battery capacity: 500mAh(lowest option)
2: 1740mAh, 1,41V, 361min Chosed battery capacity: 1600mAh
3: 2154mAh, 1,40V, 373min Chosed battery capacity: 1900mAh
4: 2100mAh, 1,41V, 366min Chosed battery capacity: 1900mAh

After refresh and analyze I thought that cell 1 was damaged and lost. But after Break-in it actually reached a higher mAh value than cell 2. But the voltage still is lower. It seems that the Break-in repaired cell 1. Another thing I can see is that the energy content of all batteries increased with Break-in but the voltage decreased. Is that normal?
While cell 3 and 4 are very close to each other 1 and 2 have a larger performance gap. What do you consider as most important: a similar voltage or a similar energy content? Are 1 and 2 now enough close to each other to work well together?


----------



## czAtlantis

Hello, it is my first post so please excuse any mistakes.
I boght this Maha MH-C9000 charger. I put the battery on a wire and set charge, 500mA and measured amps with A-metter. I thought that it will be 500mA. But the current is 2A for like 0,5seconds and than few seconds rest and again. I know in average it will be 500mA but is this gentle to the batteries? I'm bit disappointed because charge this expensive should regulate current precisely (at least i thought it will be... ) It looks this will kill them soon, specially I want to charge some AAAs (500mAh) which I want to charge only at 200mA and I'm afraid that the 2amps will kill them very soon.
I wanted all batteries charge at around 0,5C (good -deltaV signal and not too fast, i don't need fast rapid super extra chargers, I have all the time of the Universe  but what I want is gentle charger to maintain long lifespan of all batteries) But it looks it is usuable only for bigger and stronger cells which will bare these 2amps...
Thanks for suggestions and tips


----------



## Mr Happy

czAtlantis said:


> I know in average it will be 500mA but is this gentle to the batteries? I'm bit disappointed because charge this expensive should regulate current precisely (at least i thought it will be... ) It looks this will kill them soon, specially I want to charge some AAAs (500mAh) which I want to charge only at 200mA and I'm afraid that the 2amps will kill them very soon.


It's not a problem, don't worry about it. It won't harm the batteries to be charged in that way. 

A good charge setting for AAA cells is 400 mA and 1000 mA (the default) for AA cells. Although the current arrives in pulses it all gets averaged out inside the batteries.


----------



## czAtlantis

Ok, thanks. And I have another question: what method is best when I want measure battery capacity? I have all cells catalogized with number and I have in Excell a table with purchase date, brand etc and I want to run like once a year capacity check.
I don't want to use break-in because I have more than 100cells and it will take very long time. Do you suggest using fixed currents (charge 1a, discharge 0,5A) or some "C" rating like 0,5C charge, 0,25C discharge? Because I have various capacities from 1500 to 2500mAh. I was thinking what i like most - run cycle 3times at cha:1A/disch:0,5A, and write down the last capacity (because some of the cells are old and not frequently used and they need to be restored) What do you think/what do you use?
Thanks


----------



## Mr Happy

I would ignore the "C" ratings. I think they can be more misleading than helpful.

For an AA cell I would use a charge current of 1000 mA and a discharge current of 500 mA. For an AAA cell I would charge at 400 mA (or maybe 500 mA) and discharge at 200 mA.


----------



## 45/70

Hi cz. The "standard charge" rate, which is usually printed on the side of most NiCd and NiMh cells, refers to the "standard" by which the capacity of these cells was determined. The rate of charge and discharge following this "standard", is a charge rate of 0.1C for 14-16 hrs, followed by a 0.2C rate discharge (_which is not usually printed on the side of cells_) for NiCd and NiMh cells. You do not have to do it that way, but that is how most reputable cell manufacturers determine the capacity of their cells.

Often for actual users, like you and me, it is preferable to discharge cells at a rate similar to the rate your cells will be discharged in use. This way you get a better idea of how they will perform in your particular application. The same applies for the charge rate. You may prefer some other charge rate, or not be able to charge your cells at an exact 0.1C rate, for example.

For a proper comparison of cells from different manufacturers, or different ages however, it is important to use the same charge/discharge rates for all cells involved. Otherwise, the results obtained will not be an accurate comparison.

Dave


----------



## czAtlantis

Thanks, I will test them at 1000mA charge and 500mA discharge. I will run 3 cycles and mark average capacity from the second and third cycle if they won't differ too much, if so, I wil re-run these 3 cycles. (i ignore first cycle anyway because some batteries are not frequently used and need at least one cycle for conditioning). I'm still exploring the Maha charger, i have it first day. The break-in mode looks good for capacity measurements but it takes too long and i'm afraid that it should be done at least two times (break-in, discharge, break in...huh)because from old batteries I won't get 100% accessible capacity from first cycle...and it takes long time...


----------



## czAtlantis

Hi i have another question - does anybody have maha power adapter for car? Does it have any electronics inside or is it just wire? I know AC adapter is 12V and car's nominal voltage is 12V too but in car there may be up to 15V - won't it destroy charger if connected directly?

Anyone tested the lowest voltage maha C9000 will work? Thanks


----------



## Mr Happy

czAtlantis said:


> Hi i have another question - does anybody have maha power adapter for car? Does it have any electronics inside or is it just wire? I know AC adapter is 12V and car's nominal voltage is 12V too but in car there may be up to 15V - won't it destroy charger if connected directly?
> 
> Anyone tested the lowest voltage maha C9000 will work? Thanks


I am 99% sure the car power adapter is just a cable with the right plug on each end. The input side of the C9000 is a switching power supply that steps down the 12 V input to the four low voltage current supplies needed by the four charging channels. If you give it more input voltage (within reason), it will just draw less current.


----------



## czAtlantis

ok, thanks. And do you know how low voltage will it accept? 
Why I ask - I don't use original power supply because:
A) It produces awful high-pitch noise and I want to sleep next to it
B) I don't want another thing in my wall-socket
C) I have one bigger 12V backed-up power supply in my room to power router+modem+wifi+switch and I want to use it for MAHA as well. But I have quite long wires so the voltage won't be exactly 12V. I have bad experience with another charger on lower voltages, it said "charging" showed right current but it didn't charge at all and produced bad charge/discharge capacities etc...


----------



## Mr Happy

I have no idea about the minimum voltage, but unless your power supply cord is very thin there won't be that much voltage drop at the charger. The C9000 is not likely to draw more than an amp unless you use the highest charge settings (although of course the 100 W backlight probably doesn't help the power consumption ).


----------



## czAtlantis

OK, 
yeah, the backlight intensity modification is on my to-do list


----------



## samgab

czAtlantis said:


> I have bad experience with another charger on lower voltages, it said "charging" showed right current but it didn't charge at all and produced bad charge/discharge capacities etc...


 
According to William, of Maha; "The MH-C9000 has a 1% tolerance in the discharge current measurement. Furthermore, the MH-C9000 uses a quartz oscilattor time base." So for charge if the input is slightly under 12V, or for discharge, I'd guess it would still be relatively accurate... I mean, it's not a piece of lab equipment, but should still do the job.


----------



## Chidwack

I got my Maho MH-C9000 this last week. I have to say that the instructions were not as complete as I would have liked but thanks to you folks here on this forum I was able to somewhat understand them. After using, testing, charging and all around playing with this charger for a few days, I have to say that I'm impressed. It's nice to know what the capacity of the different batteries that I have in storage actually is instead of just guessing. I can now deploy batteries as a set that I know are evenly matched. I am now doing a break-in on some new eneloops that I just got today. I'm somewhat dreaded starting the break-in on these batteries because it ties up the charger for a couple of days on just 4 batteries but at least I will know that 4 of the eneloops are ready to go at peak levels. 

Thanks again for everyone here that posted great advice, especially Mr. Happy.


----------



## gggggg

How would you guys suggest to treat (which modes to use) brand new 800mAh NiCd cells (especially regardgin the 100mA topp off) ? 
1. For the first cycles (break in?)
2. Further on (do all charge modes have the top off ?)


----------



## TakeTheActive

gggggg said:


> How would you guys suggest to treat (which modes to use) brand new 800mAh NiCd cells?



Run a 200mA DISCHARGE followed by a 800mAh BREAK-IN and report both results.
.
What is the planned purpose of these 800mAh NiCd cells?
.
Are they AAA or AA?
.
Who is the manufacturer?


----------



## gggggg

1. It is AA from China. I did the Break in already. The label said 900mAh and it reaches 800mAh. 
.
2. I bought it, because NiCD id more robust than NiMh. They sit in an electronic valve for about 8 month controlling room temperature and as the valve moves quite seldom, they are continously bufferd with about 8mA. The rest of the year (4 month) they valve is disabled. 
.
3. So I thought maybe its a good idea to form them once or twice a year (which mode?) 
.
4. Is there a charge mode without top off on the C9000 ?


----------



## samgab

gggggg said:


> 1. It is AA from China. I did the Break in already. The label said 900mAh and it reaches 800mAh.
> .
> 2. I bought it, because NiCD id more robust than NiMh. They sit in an electronic valve for about 8 month controlling room temperature and as the valve moves quite seldom, they are continously bufferd with about 8mA. The rest of the year (4 month) they valve is disabled.
> .
> 3. So I thought maybe its a good idea to form them once or twice a year (which mode?)
> .
> 4. Is there a charge mode without top off on the C9000 ?



Ni-Cads have less self-discharge than traditional NiMH cells, but still something like 20% per Month, and still a lot more than LSD NiMH cells. Eneloop cells may, IMHO, have been a better choice. On the other hand, that trickle charge probably wouldn't have done them any good...
Please read the C9000 manual and the Maha C9000 FAQ carefully first. It answers your questions best about the charge modes etc.


----------



## gggggg

Thanks for the links, but I read through those (no help on my questions) and a lot of other related posts over the last two weeks ... and I did not keep it all in mind :bow:

*1. Is there a charge mode without topoff on the C9000 ?*
different findings:




Originally Posted by *willchueh* 

 
2-Hour top-off charge is applied in all modes *except in DISCHARGE and BREAK-IN*.




Originally Posted by *MH-C9000 Manual* 
_9. When the program for a slot is completed, DONE will be displayed to the right of the bank number. With the *exception of DISCHARGE* mode, topoff charge and trickle charge (continuous) will be applied._


*2. Is topoff applied during restperiodes of Cycle and R&A mode or only at the end ?
*There was a discussion going on but without conclusion for me...*

3. Any display that tells, "topoff has been finished" *(it seems that the (trickle) current is not displayed after DONE, can the voltage display help...) *?

4. Regarding storage *(I read post from SilverFox): *Does it make any difference whether 
*a) to charge and discharge to e.g. 40% of capacity and store or 
b) to discharge and charge to 40% before storage ?

*5. Is there realy no difference between R&A and Cycle=1 ? *(because manual states: "On bad bat use R&A 1-3 times" .. they could have said "use cycle set to 1-3")


----------



## zrike

Hi, not sure if this is the right place, but since my question is about the C9000 and I see other people in this thread asking questions about the C9000, I hope it is.

I've been having to buy more batteries lately, so I've decided to get into rechargeable batteries. After reading reviews on amazon, I had _thought _I had narrowed it down to the BC-700 or BC-1000, ignoring the C9000 because of the cycling display, bright lcd, and many button pushes. Then I watched some videos of them all on youtube(well, the 900 in the case of the 1000) and found that the cycling/button pushing did not look nearly as bad as I thought.

I'm willing to spend the money on the C9000, but I just have one last concern. Is there a way to deal with the bright lcd? Could I cover it up with something safely? If I ever get up the courage is there a hardware solution? If there is a way to cope with the brightness, then I'll definitely get this over the BC-700/1000.

Thanks.


----------



## 45/70

Hi gg. I'll try to answer your questions.

#1

Obviously, when a "DISCHARGE" is performed, there will be no "top off", or "trickle charge", as the discharge function is just that, a discharge, and there is no charging taking place at all.

As far as the "BREAK-IN" function, it would be rather pointless to apply either the "top off", or the "trickle charge", as the cell is being overcharged (at an acceptable rate) by a significant amount anyway.

So, as Will states, these are the only two modes, or functions, where both the top off and trickle charge are absent. If you are asking "is there a way to eliminate the top off charge when using the other functions", the answer is no.

#2

That's a good question and I'm not really sure. I've haven't used the "CYCLE" function much, but I think it does in both "CYCLE" and "R&A". I always thought anyway, that is why the rest period is 2 hrs after charging, and only an hour after discharging. Again though, I'm not certain on this one. I'll have to watch more closely the next time I R&A, which I really don't use very often either.

#3

No, there is no portion of the display that tells you when the "top off" is completed. You are correct though that by watching the voltage you can determine when the top off is completed. After the actual charge (at the full rate) is completed and "DONE" appears on the display, the voltage of the cell will begin to slowly drop. At a certain point, the voltage will again, begin to rise, very slowly. When after the two hours expires, the top off charge current will lower from 100mA to ~10 mA (trickle rate). When this happens, the voltage of the cell will again begin to drop. This is evidence that the top off charge has completed.

#4

I don't believe it would make any difference.

#5

Yes, I think they are the same. Keep in mind though, that the "CYCLE" function allows more than one charge/discharge, whereas with R&A, the cell will only be cycled once. I think it is for this reason, that both functions are available, otherwise yes, they're the same.

Hope this helps,

Dave


----------



## Burgess

to Zrike --


Simply put a Post-It Note over the illuminated display.

Nothing to it !

This is a WONDERFUL charger -- GET IT ! ! !


:thumbsup:
_


----------



## samgab

Plus it makes a really good night light...


----------



## NoixPecan

45/70 said:


> #2
> That's a good question and I'm not really sure. I've haven't used the "CYCLE" function much, but I think it does in both "CYCLE" and "R&A". I always thought anyway, that is why the rest period is 2 hrs after charging, and only an hour after discharging. Again though, I'm not certain on this one. I'll have to watch more closely the next time I R&A, which I really don't use very often either.


I also think that a top-off current is applied during the two-hour _REST_ period of the_ R&A_ program. It was not the case with the first version of the C9000 though.

SilverFox was among the first to report that change :


SilverFox said:


> I was using the Refresh/Analyze mode.
> 
> My original charger would charge first, rest for an hour, discharge, rest, then charge back up. During the rest period between charging and discharging I would see the voltage gradually settle down from the peak charge voltage.
> 
> My newer charger does this differently. It still follows the same sequence, but the rest time between charging and discharging is now two hours, and the voltage holds steady. It is as if there is now a top off charge being applied during the rest period.


----------



## SilverFox

I have to say that I rarely use cycle and R&A, so I don't know how the top off charge performs during those uses. Fortunately, NoixPecan reminded me of part of my confusion. The function changed with the change in the early units. If the hold time is 2 hours, 1 hour of that is top off charge.

It is important to attend to your charge, so the illumination of the back light is basically a non issue, but you can always wear sun glasses...  

As far as storage goes, the ideal way to store NiMh cells is to completely discharge them to 0.9 volts per cell. Then, every 30 days subject them to a charge/discharge cycle.

Tom


----------



## N162E

SilverFox said:


> As far as storage goes, the ideal way to store NiMh cells is to completely discharge them to 0.9 volts per cell. Then, every 30 days subject them to a charge/discharge cycle.
> 
> Tom


To charge/discharge Eneloops every 30 days would totally defeat their purpose and waste cycles. Plus I would think that storing non LSD cells in a fully discharged state would be the quickest way to really ruin them.

If I am missing something here please correct me.


----------



## Russel

Performing a charge/discharge cycle every thirty days would take something like 82 years to complete 1000 cycles. (Current Eneloops are rated at 1500 cycles.) The LSD cells would die of old age long before being wasted away from a cycle every 30 days.


----------



## Wrend

Regarding Eneloops, from their FAQ:



> *Should I store my batteries charged or uncharged?
> *If stored with charge, it is possible that when you return to use the battery there may still be some charge left in the battery, therefore it will enable you to use it right then and there. Also, by keeping some charge in the battery, it will require you to "cycle" the battery fewer times until it reaches its peak charge. If you store them with no charge, you will have to "cycle" the battery multiple times until it reaches its peak charge.



I personally store mine charged so that they're ready to use whenever I need them and charge the depleted cells I swap out.


----------



## Mr Happy

N162E said:


> To charge/discharge Eneloops every 30 days would totally defeat their purpose and waste cycles. Plus I would think that storing non LSD cells in a fully discharged state would be the quickest way to really ruin them.
> 
> If I am missing something here please correct me.


I don't think this advice applies so much with eneloops. It is most appropriate for traditional NiMH cells with normal levels of self-discharge. Although I don't think you would lose very much if you stored them discharged and only cycled them once a year rather than once a month. The most important thing with normal NiMH cells is to store them discharged as this minimizes the energy bound up inside them (a bit like storing a spring without tension on it to preserve its springiness).

As far as eneloops are concerned I don't do anything special to maintain them. I just use them and charge them when needed.


----------



## N162E

Mr Happy said:


> I don't think this advice applies so much with eneloops. It is most appropriate for traditional NiMH cells with normal levels of self-discharge. Although I don't think you would lose very much if you stored them discharged and only cycled them once a year rather than once a month. The most important thing with normal NiMH cells is to store them discharged as this minimizes the energy bound up inside them (a bit like storing a spring without tension on it to preserve its springiness).
> 
> As far as eneloops are concerned I don't do anything special to maintain them. I just use them and charge them when needed.


Thank you and +1


----------



## taichicali

Hi Everyone,

I just bought this charger and put in 4 AA 2500 capacity Sanyo XX eneloops into the charger in break in mode.

My readings are now:
1.47 volt
3425MAH
250MA
907 Min

Should I be concered with the 3425 number? Are my batteries being overcharged? Help?
Thanks
Tai


----------



## shadowjk

It will put 1.4-1.6 tiems the capacity you netered into the battery during break-in. That's what it's supposed to do.


----------



## taichicali

shadowjk said:


> It will put 1.4-1.6 tiems the capacity you netered into the battery during break-in. That's what it's supposed to do.



Oh, cool. Thanks so much for your quick response :wave:


----------



## Burgess

Post removed


----------



## samgab

taichicali said:


> Hi Everyone,
> 
> I just bought this charger and put in 4 AA 2500 capacity Sanyo XX eneloops into the charger in break in mode.
> 
> My readings are now:
> 1.47 volt
> 3425MAH
> 250MA
> 907 Min
> 
> Should I be concered with the 3425 number? Are my batteries being overcharged? Help?
> Thanks
> Tai



Since you set it at 2500 break-in, it will charge for 960 minutes at 250mA up to 4000mAh, then will rest for an hour, then discharge at 500aH for about 5 hours or until the cells are at 0.9V, then rest for an hour, then charge again at 250mA for 960 min up to 4000mAh. After it has completely finished after about 39 hours, the result displayed will be the discharged amount, or the cell capacity.

Ignore the post 1 above this... He clearly didn't realise you're doing a BREAK-IN. In which case the rate is fine, because it's a timed charge for exactly 16 hours. You're doing it right.


----------



## Wrend

The XX cells come pre-charged I imagine. If you didn't discharge them first, then they are going to be overcharged during the first charge phase of the break in cycle. Not the end of the world, but still not the best for the cells.


----------



## Beacon of Light

So I have older cells that were rarely used that show HIGH on the C9000. I have tried the discharge and they show DONE immediately. I also try the Break in and then it asks for cell capacity, and then it goes right to charge and then it blinks as if the cell was remnoved and re-installed. Not sure if this is supposed to happen, but how do I revive these cells? Weird thing is I can charge them normally on my LaCrosse BC900 just fine. Ironically the C9000 is supposed to be able to revive old cells but it does a worse job at this and in order to use these cells on the C9000 I have to trick it by putting it in a dumb charger first. How smart is that for a smart charger like C9000?


----------



## Rexlion

I think the charger has decided that those cells are junk. If you charge them up on your LaCrosse and do a discharge on the Maha to see how much capacity these old cells have, you may find that you agree with the Maha charger. They probably don't hold enough charge to bother with anymore. The LaCrosse is a dumb charger, literally... it is too dumb to know when it's time to give up on a crappy old cell.


----------



## 45/70

Beacon of Light said:


> ......How smart is that for a smart charger like C9000?



Well actually, as Rexlion said, the C9000 is quite a bit smarter than the La Crosse.

When cells respond to charge attempts, as you describe, they are usually in a condition of no repair. When they're that bad, no amount of conditioning will bring them back to performing satisfactorily for most uses.

You mention that these cells were "rarely used". With conventional NiMh cells (and NiCds,as well), one of the worst things you can do to them, is not use them. This does not apply, as much anyway, to LSD NiMh cells, although it doesn't hurt to keep them active either, for maximum performance. Non use however, will kill conventional NiMh cells.

As for the C9000's ability to "restore bad cells", this is possible, provided that the cells are not too far gone. I view the features of the C9000 as better at preventing cells from going bad, rather than restoring them however.

All that said, I do use my BC900 for charging cells that are in "not so good shape". I don't have, or keep cells as bad as yours though. Most cells that initially show up "HIGH" on the C9000, are still useable in low current drain devices such as clocks, indoor/outdoor thermometers and such, so I do have a few AAA and AA "HIGH" cells that I use. I just can't see using a perfectly good eneloop in something that draws 1 milliamp, for example.:shrug:

Devices that draw a minimal amount of current are one of the few types of use, where cells that return a "HIGH" reading on the C9000 can still be used. The "HIGH" means these cells have high internal resistance and the associated voltage depression that comes with it, and is also why the cells say "DONE" soon after put on discharge (the cell voltage drops substantially, under the C9000's pulsed 1A current load). This associated voltage depression has much less effect in a cell's performance when used in low drain devices, and allows me to use my "good" cells in more tortuous applications.

Dave


----------



## samgab

I wanted to see exactly how close to the displayed reading the C9000 charger actually is.
The Fluke 87 V has a handy averaging feature, which is good for pulsed charging like this.
Excuse the low quality and the vertical format, I recorded it on a phone:

So the actual current is about 880mA when the screen is displaying 994mA, on a charge rate setting of 1000mA.
That's in bay one of my particular C9000 anyway.


----------



## bbb74

samgab said:


> I wanted to see exactly how close to the displayed reading the C9000 charger actually is.The Fluke 87 V has a handy averaging feature, which is good for pulsed charging like this.Excuse the low quality and the vertical format, I recorded it on a phone:So the actual current is about 880mA when the screen is displaying 994mA, on a charge rate setting of 1000mA.That's in bay one of my particular C9000 anyway.


So its pretty accurate then, as there is an "off" period of 10% where there is no charging, when the charger is checking the battery's voltage etc. On the C9000 a charge rate setting of 1000mA is a rate of 1A but at 90% duty cycle, so about 900mA averaged.


----------



## samgab

bbb74 said:


> So its pretty accurate then, as there is an "off" period of 10% where there is no charging, when the charger is checking the battery's voltage etc. On the C9000 a charge rate setting of 1000mA is a rate of 1A but at 90% duty cycle, so about 900mA averaged.



When my charger is set to 1000mA it charges at a pulsed rate of 1931mA with a 46% duty cycle.
I tested at 2000mA and 200mA as well, and the pulses were shorter. The same time increment, but shorter duration or longer duration pulses. Whatever setting I chose, the rate was always ~1931mA.


----------



## bbb74

Sorry you are right I got myself mixed up, its ~2A (1931mA as you measure). What I meant to say was my understanding was that what you set on the screen is the peak rate and you have to subtract 10% for the actual average charge rate after taking out a 0.2s pause every 2 seconds for the charger to do measurements. I saw a post from a Maha staffer about it when they were answering questions.


----------



## samgab

bbb74 said:


> Sorry you are right I got myself mixed up, its ~2A (1931mA as you measure). What I meant to say was my understanding was that what you set on the screen is the peak rate and you have to subtract 10% for the actual average charge rate after taking out a 0.2s pause every 2 seconds for the charger to do measurements. I saw a post from a Maha staffer about it when they were answering questions.



Yes, that's right. So the 90% of the set rate in the video would have been 900mA, which it actually measured pretty close to.
I recorded videos of the 200mA and 2000mA rates, so I'll put them up when they finish uploading on youtube.
Later I might check all the other bays at more rates and see how they compare.


----------



## samgab

Set to 2000mA:

Averages a reading of 1760 mA with a 1930 mA rate, so 91% duty cycle.

and set to 200mA:

Averages a reading of about 180 mA with a ~1910 mA rate, so about a 9% duty cycle.


----------



## TakeTheActive

*That Was an Interesting 'Experiment'!*



samgab said:


> I wanted to see exactly how close to the displayed reading the C9000 charger actually is.
> The Fluke 87 V has a handy averaging feature, which is good for pulsed charging like this.
> Excuse the low quality and the vertical format, I recorded it on a phone:
> 
> ...So the actual current is about 880mA when the screen is displaying 994mA, on a charge rate setting of 1000mA....


That was an interesting 'Experiment'!






Thanks for taking the time to create movies and then upload them to YouTube - makes one feel like they were standing right next to you watching. :thumbsup:


----------



## TakeTheActive

*Visual Confirmation of What Mr Happy Has Been Saying All Along...*

Paraphrasing:


samgab said:


> Set to *2000mA*:
> 
> Averages a reading of 1760 mA with a 1930 mA rate, so *91% duty cycle*.
> .
> Set to *1000mA*:
> 
> So the actual current is about 880mA when the screen is displaying 994mA, on a charge rate setting of 1000mA... ...it charges at a pulsed rate of 1931mA with a 46% duty cycle. [2X = *92% duty cycle*]
> .
> Set to *200mA*:
> 
> Averages a reading of about 180 mA with a ~1910 mA rate, so about a 9% duty cycle.[10X=[B]90% duty cycle[/B]]


Visual confirmation of what *Mr Happy* has been saying all along - a constant *~2000mA* Charge Rate for *ANY* setting, pulsed for different lengths of time, which, in the end, averages out to *~90% Duty Cycle*.


----------



## DT 123

The last days I spent hours to read the two FAQ threads. I learnt a lot. But I have also some questions:

1) 
Why isn't it mandatory for all to read them first before they can post here a question? I could have saved several hours since many questions are asked again and again. Reading an answer 2 or 3 times is fine - i know them by heart now. But 10 or 20 times the same question ... :-(

2) 
But now the real question. I did a break-in test with an old set of GP 1800. 
They had a capacity of 1330 / 1275 / 1290 / 1186 mAh.
Some hours after the break-in i discharged them - the first 2 on the C-9000 @400mA, the other 2 on a IPC-1L (which is a relabelled BC-700) @350mA.
The results were 1273 / 1116 / 1402 / 1329 mAh.

What i should conclude? 
- I know that the break-in results (@360mA) on the C-9000 should be slightly higher than the discharge ones @400mAh - finally there is a 10% difference.
- But the 350mA & 360mA are very similar. So the difference comes only from the pulse discharging? Or does a BC-x00 always discharde 'better'?

The difference vary more than i expected. Can i conclude that these cells will have more problems with high A? 
Will the results of new cells (eg eneloops) be more similar (less differences between BC-700 & C-9000)?


Remark: The cell #2 had at this test a very low voltage while discharging (it started already at 1.07V).


----------



## Russel

*Re: Visual Confirmation of What Mr Happy Has Been Saying All Along...*

Here are some oscilloscope displays of the C9000 charging at 1000mA and 2000mA so that you can see how the charge rate is varied.

The MH-C9000 charging at the 1000mA setting:








The MH-C9000 charging at the 2000mA setting: (Note that each vertical division represents 200ms or 0.2 seconds)


----------



## tobrien

*Re: Visual Confirmation of What Mr Happy Has Been Saying All Along...*

does Maha publish a changelog for their firmware revisions?


----------



## bbb74

*Re: Visual Confirmation of What Mr Happy Has Been Saying All Along...*

Thanks samgam and russel, good work. Love those oscilloscope graphs that shows it in an easy to understand way!


----------



## Mr Happy

DT 123 said:


> I did a break-in test with an old set of GP 1800.
> They had a capacity of 1330 / 1275 / 1290 / 1186 mAh.
> Some hours after the break-in i discharged them - the first 2 on the C-9000 @400mA, the other 2 on a IPC-1L (which is a relabelled BC-700) @350mA.
> The results were 1273 / 1116 / 1402 / 1329 mAh.
> 
> What i should conclude?


The C9000 is a bit more demanding on cells during the discharge. Although the average current is 400 mA (360 mA) it is done with short high current pulses, whereas the BC-700 uses longer pulses of lower current.



> Can i conclude that these cells will have more problems with high A?
> Will the results of new cells (eg eneloops) be more similar (less differences between BC-700 & C-9000)?


Essentially yes, I would say so.



> Remark: The cell #2 had at this test a very low voltage while discharging (it started already at 1.07V).


That also suggests the cell will have trouble at high discharge currents.


----------



## DT 123

I did with cell #2 a second break-in (a half one since i stopped after the discharging). The result were this time 1245 mAh.

After some rest i charged the cells with 1000mA (1405 mAh) on a CM 4200. Some rest and again a discharge with the C-9000 @400mA. The Maha was done after 377 mAh. Which shows that the cell is behaving now more badly with higher currents. @100mA I could still discharge 934 mAh.

Is it possible to recover such a cell for higher current again or does the cell call for a remote control?

After charging a top off will be applied. If i didn't set a timer. Is there a way to find out whether I am still in the top off time or already in the trickle time?

Comparing the discharging results of the C-9000 and BC-700 and reading what you wrote - does this mean that in generally i can never compare capacity results i get from different chargers, since they behave different? If it is so, then the '80%-crap-cell-rule' is also relative and could be 75% on charger #1 and 80% on charger #2?

I have a dead NiCd cell. The impedance check of the charger says 0.0 V. My other chargers give me an error after some minutes. But the C-9000 is trying for minutes to 'access' the cell @125mA. I gave always up after a while and removed the cell. Shouldn't be there a timeout or something like that? I don't dare to let the cell too long in the charger.


----------



## DT 123

I found a partly answer to the NiCd issue:

http://www.candlepowerforums.com/vb...odd-behavior&p=3188866&viewfull=1#post3188866


----------



## SilverFox

Hello DT 123,

When sorting cells for demanding use, I consider the cell is CRAP when its capacity drops below 80% of its capacity when new. Looking at your 1800 mAh cells, when new they were probably capable of around 1650 mAh. 80% of that comes out to around 1320 mAh. 

If your cell during a standard charge and standard discharge give you a capacity lower than 1320 mAh, they are not good candidates for demanding use.

If cells pass that test the next thing to check is their voltage under load. If the voltage under load is low, the cell has internal problems. 

Sometimes a few charge/discharge cycles can help, but often the cells end up in the CRAP pile to be recycled.

Tom


----------



## DT 123

As standard charge you count for the C-9000 the charging incl the 2 hour top-off? 
As i remember right (it took me too long to read all the FAQ  ) then you mentioned as mid point voltage something like 0.5C & 1.2V for the AA.
Assume that these cells have still 1400mAh. The 0.5C to check are in this case after discharging 900, 825 or 700 mAh?

I charged the cell #2 on the C-9000 @1A and i am doing now after some hours rest the discharging @400mA. It started with 1.22V under load - at least a big improvement compared to the 1.07V from 2 days ago.
However it dropped pretty fast to 1.18V which is lower than 'your' 1.2V.
Can i expect that after some charge/discharge the cell will recover still more or will it drop soon again to its old behaviour and won't like higher current?
Would a higher or lower current for charging/discharging be better - or doesn't it matter? 
I wouldn't think that a lower current would help since even after the 2 cycle of break-in the voltage under load stayed low.


----------



## SilverFox

Hello DT 123,

A standard charge is charging at 0.1C with a timed termination at 16 hours. A standard discharge is a 0.2C discharge. The C9000 comes close to this with the Break In function.

An ideal mid point voltage for NiMh cells is 1.2 volts. You can adjust your expectations according to the current draw you are using. Higher current draw will result in lower mid point voltages.

Cycling the cells through charge/discharge cycles sometimes helps and other times it doesn't. You just have to try it and see what happens. When I am working with questionable cells I use charge and discharge currents that warm the cell. I think this helps the chemistry along, but I don't have a lot of science to back this up.

Tom


----------



## 45/70

*Re: Visual Confirmation of What Mr Happy Has Been Saying All Along...*



tobrien said:


> does Maha publish a changelog for their firmware revisions?



Not that I am aware of. I'm pretty sure there has only been one firmware revision since the C9000 was introduced. That was years ago, shortly after it came out. There have been some mechanical changes to the charger, but I think it's still running on the first revision firmware.

Dave


----------



## shadowjk

DT 123 said:


> Can i conclude that these cells will have more problems with high A?



This has been my experience with C-9000 vs BC900, the capacity of discharge test as shown by C-9000 represents more demanding workloads, and BC-900 will give you a capacitive representative of what you'd get in non-demanding workloads.


----------



## tobrien

*Re: Visual Confirmation of What Mr Happy Has Been Saying All Along...*



45/70 said:


> Not that I am aware of. I'm pretty sure there has only been one firmware revision since the C9000 was introduced. That was years ago, shortly after it came out. There have been some mechanical changes to the charger, but I think it's still running on the first revision firmware.
> 
> Dave


gotcha, thanks bud! I was under the impression that there were regular firmware revisions based on how you guys post haha

Thanks man!


----------



## DT 123

*Re: Visual Confirmation of What Mr Happy Has Been Saying All Along...*

Out of curiosity - how much energy does the wall wart spend when it is used with 110V? I measure here @230V 0.25-0.3 W for the standby mode (2011 model of the C-9000) and as far i remember (the chargers are busy at the moment) the chargers used about 0.9W in sleep mode.
Are there any differences for 110V and 230V?

And the up to 20.000 mAh supported capacity appears also still in the 2011 reprint of the manual. 
English (online 2007 / printed 2010)
German (online 2009 / printed 2011)
Dutch (online 2009/ printed 2011)
Perhaps they only change the year when they run out of manuals?


----------



## DT 123

*Off topic*

Do you have also sometimes the problem that after posting everything is not formatted?
All my carriage returns in my last post disappeared - so i had to edit it again.


----------



## DT 123

I just finished my first break-ins on 2 C-9000 with AAA eneloop cells (bulk 2011/06).


Code:


            		Charger 1           		Charger 2
            		#1	#2	#3    	#4	#5	#6	#7	#8

Discharge @200mAh    	585	598	602	600	585	602	594	598
Break-In        	812	815	820	819	807	822	813	820


I conclude that there seems to be not much difference between the 2 charger. Very interesting was also to compare the discharge & break-in values.
The slightly better cells while discharging were also the better ones after the break-in.
A waste of time to do a break-in at this time? Or would have all cells benefited equally?


----------



## DT 123

I never paid attention to the charging results while doing a break-in. Now I did the first time and it confused me. I did a 2000 break-in and the charging results after 16 hours differed by 10 mAh. This is a difference of about 3 min @200mA. Where does this difference come from?

Will each slot be charged slightly differently (since they are independent)? 
Does this effect also discharging? Or does this not matter in normal mode since the C-9000 is counting the pulses and then it doesnt matter in which slot the cell was inserted?


----------



## SilverFox

Hello DT 123,

Each channel is independent, so you can expect variations. They are usually close, but not exact.

Tom


----------



## samgab

I did some more testing with the Fluke:

*setting**slot**displayed rate**min**max**avg**% of Displayed rate*20011972191017488%20021982186917086%20031972186816986%20041972183916684%*200 Average*
*197**2**1872**170**86%*50014942192343889%50024952188642686%50034942188642887%50044942185542586%*500 Average*
*494**2**1888**429**87%*100019902192387588%100029892188386287%100039882188786387%100049882185585086%*1000 Average*
*989**2**1887**863**87%*200011980221923175589%200021981211884171887%200031983211891172787%200041976211855169586%*2000 Average*
*1980**21**1888**1724**87%**Grand Average*

*7**1884**796**87%*






*setting**slot**displayed rate**min**max**avg**% of Displayed rate*-1001-993-996-8889%-1002-983-977-8688%-1003-1003-998-8787%-1004-993-986-8687%*-100 Average*
*-99**3**-989**-87**88%*-2001-1993-1004-18090%-2002-1973-986-17488%-2003-2003-1007-18291%-2004-1983-994-18091%*-200 Average*
*-199**3**-998**-179**90%*-5001-4993-1004-45291%-5002-4943-985-44790%-5003-5003-1007-45791%-5004-4963-994-45091%*-500 Average*
*-497**3**-998**-452**91%*-10001-999-7-1003-91692%-10002-990-7-985-89891%-10003-1001-8-1006-91892%-10004-992-7-993-90491%*-1000 Average*
*-996**-7**-997**-909**91%**Grand Average*

*0**-995**-407**90%*



The readings are all in mAh. The negative readings are for discharge, and positive ones are for charge.


----------



## samgab

Charts for the discharge results:


----------



## DT 123

Why did you compare to the displayed rates? You are assuming that that rate is used for the calculation of the total amount?
The C-9000 is showing the rate only every 60 sec - do we know whether the present current is shown or the average current of the last minute?
Since the test running time was longer than one minute - did you average also the display rates? 

But it was a very interesting test. First of all since for charging slot #4 had the lowest current, but for discharging it was slot #2.
Any idea what could be the reason for that?


----------



## samgab

DT 123 said:


> Why did you compare to the displayed rates? You are assuming that that rate is used for the calculation of the total amount?
> The C-9000 is showing the rate only every 60 sec - do we know whether the present current is shown or the average current of the last minute?
> Since the test running time was longer than one minute - did you average also the display rates?
> 
> But it was a very interesting test. First of all since for charging slot #4 had the lowest current, but for discharging it was slot #2.
> Any idea what could be the reason for that?



I compared the unit's displayed rate, because that is the charge rate that it is _saying _it is charging or discharging at. I wanted to compare that to the rate it was _actually _charging at.
I tested one bay at a time, so I was getting the unit's rate much more frequently than every 60 seconds. And I checked it multiple times before taking down a reading to confirm that it is a stable, non-changing reading. The rate displayed doesn't really change it stays pretty much constant.

The differences are most likely because the C9000 is not a precision item of lab equipment. 
It is just a consumer battery charger/analyser. They use multiple components inside that probably have quite (relatively) large margins for error, and tolerances.
The Fluke 87V, on the other hand is a precision piece of equipment.

I don't know the _exact_ reason why one particular bay would be higher than the others whilst lower than the others for discharging (that would require disassembling the unit and testing each component separately), but I'd say generally it's because each slot is independent from the others, and some different components are used for charging than for discharging. So it would make sense that how one compares to the others in charging wouldn't necessarily correlate to how it compares to the others when discharging.


----------



## DT 123

I still think that something is wrong with the test/data. If you found out that the displayed rates are differing in average by 10% by your measured rates then this would finally mean that the C-9000 is giving us for charging & discharging results which are 10% too low. This means that when the c-9000 is measuring a capacity of 2000 then in reality it should be 2200 mAh. But this cannot be true. This also doesnt match to the 2% capacity accuracy while doing the break-in.


----------



## Wrend

The capacity measurement is calculated differently, from what I remember. If you read the current rate on the C9000 and time out how long its on there, it won't match up with the capacity because of this difference.

The capacity measurement, especially on the break in function, is accurate.


----------



## DT 123

Because of the 10% (?) 'service break'. As far as i remember we should multiply by 0.9. But even then i get different results:
#1:
shown current: 194mA * 16 hour * 0.9 = 2794 mAh. The c-9000 shows me 2824. 
#2:
shown current: 244mA * 16 hour * 0.9 = 3514 mAh. The c-9000 shows me 3592. 

Rounding because of display: 0.5 mA * 16 hour * 0.9 = 7.2


----------



## samgab

DT 123 said:


> I still think that something is wrong with the test/data. If you found out that the displayed rates are differing in average by 10% by your measured rates then this would finally mean that the C-9000 is giving us for charging & discharging results which are 10% too low. This means that when the c-9000 is measuring a capacity of 2000 then in reality it should be 2200 mAh. But this cannot be true. This also doesnt match to the 2% capacity accuracy while doing the break-in.



As Wrend said, the displayed discharge _amount (mAh)_ is calculated differently than the discharge _rate (mA)_ and is accurate (within 1-2%).
The capacity calculation is based on the _actual _current rather than the set (or displayed) current so capacity calculation remains accurate. 
According to Will Chueh of Maha, "The MH-C9000 has a 1% tolerance in the discharge current measurement."
Also from Will: "The displayed charging/discharging rate does not include a ~10% off-time. For example, when you set current to 2.0A, it will charge at 2.0A for 90% of the time and rest for 10%. Of course, the capacity reported includes this effect." The ~ means "about", so it isn't necessarily precisely 10%, as shown by my testing.
A way to test the capacity accuracy in comparison to the displayed rate yourself is to use a stopwatch. Discharge a fully charged AA at a set 1000mA for exactly 1 hour and check the readout for capacity vs it's rate.
I did this with 4 eneloops and the result for slots 1-4 was 915, 907, 920, 911 mAh displayed, respectively. On par with my test results. 
The C9000 discharge _rate (mA)_ display though, read 999, 990, 1002, and 992 respectively.
Each unit might differ by a little bit, because it's not a calibrated instrument, but a few mAh here or there aren't a major concern.


----------



## DT 123

I did some cycle tests after a break in with some of my older cells:



Code:


Varta 1600, Cycle @ 800/500 mA

		#1	#2

Break-In	1284	1336
Cycle 1		1257	1292
Cycle 2		1212	1250
Cycle 3		1209	1249

Ansmann 2500, Cycle @ 1000/500 mA

		#1	#2

Break-In	2001	2020
Cycle 1		1928	1953
Cycle 2		1870	1886
Cycle 3		1843	1867


GP 1800, Cycle @ 1500/400 mA

		#1

Break-In	1245
Cycle 1		1200
Cycle 2		1197
Cycle 3		1182



Shouldn't the cycle improve the capacity of a cell? 
Is it an accident that the capacity dropped each time (from cycle to cycle) and the cycle results are still within the range to be seen as the same? 
For the GP i would think so. But what could be the reason for the drop from cycle 1 to cycle 2 for the Varta & Ansmann cells?


----------



## SilverFox

Hello DT 123,

Interesting trend...

At the rate things are going, your cells may be used up in another 10 - 20 cycles. Perhaps you should run another test of 10 cycles and see if things turn around or continue to decline.

Tom


----------



## DT 123

I started another cycle test. Results continue to drop or reach a stable value. I started also another cycle test with some older Sanyo Twicell 1600 & some newer LSD Panasonic Infinium 2000. The tests are still going on, but what I get was not was I was really waiting for:



Code:


Varta 1600, Cycle @ 800/500 mA	|	Ansmann 2500, Cycle @ 1000/500 mA
				|
		#1	#2	|	#1	#2		
				|
Break-In	1284	1336	|	2001	2020
Cycle 1/3	1257	1292	|	1928	1953
Cycle 2/3	1212	1250	|	1870	1886
Cycle 3/3	1209	1249	|	1843	1867
Cycle 1/10	1238	1273	|	1808	1843
Cycle 2/10	1191	1227	|	1807	1832
Cycle 3/10	1192	1231	|	1789	1820
Cycle 4/10	1190	1224	|	1766	1807
Cycle 5/10	1193	1213	|	...	...
Cycle 6/10	1189	1218	|	...	...

Sanyo Twicell 1600, Cycle @ 800/500 mA

		#1	#2	#3	#4

Break-In	1402	1267	1177	1230
Cycle 1/3	1286	1209	1030	1153
Cycle 2/3	1258	1196	996	1121
Cycle 3/3	1249	1200	969	1132


Panasonic Infinium 2000, Cycle @ 1000/500 mA

		#1	#2	#3	#4

Break-In	1893	1933	1947	1913
Cycle 1/3	1872	1910	1930	1893
Cycle 2/3	1835	1888	1899	1861
Cycle 3/3	1838	1885	1894	1864


You mean that certainly most of the cells are already dead. 
I have to add that all cells had not more than 20-50 charging cycles before these tests.
But I am pretty sure that some of them were killed by letting them in an Ansmann energy 8 charger(@trickle) for too long. So certainly they dried out? But then again - shouldn't I get then from the beginning the low results?

The only real increase I reached at cycle 1/10 for the Varta cells. But these cells were the only ones who rested long enough between 2 cycles and got finally 2 times the top off charge - once after the last charging at cycle 3/3 and then again for the first charge at cycle 1/10.
None of the cells did become too hot while charging.

So - why there is the drop between cycle 1 and cycle 2 for all of the cells?


----------



## SilverFox

Hello DT 123,

Good question... I don't know the answer.

However, I can speculate that it may involve variables with electrolyte changes, internal cell resistance, and temperature. I can say that fresh new cells behave differently than aged cells. One of the issues with using loose cells as a battery is matching them. Aged cells need to be viewed over several cycles until their performance characteristics are stable. Fresh cells are much more stable once you get past the initial break in.

Tom


----------



## tobrien

just bought a C9000 for $44 off of Amazon through their "warehouse deals" thing. description said "very minor packaging flaws/damage" but that the item is in excellent condition. 

i can't wait to join this C9000 club 

free two-day shipping too, since I'm an Amazon Prime member


----------



## DT 123

@Tom:
After doing some cycles I was curious what results a new break-in would show:



Code:


Ansmann 2500, Cycle @ 1000/500 mA

		#1	#2

Break-In	2001	2020
Cycle 1/3	1928	1953
Cycle 2/3	1870	1886
Cycle 3/3	1843	1867
Cycle 1/9	1808	1843			
Cycle 2/9	1807	1832
Cycle 3/9	1789	1820
Cycle 4/9	1766	1807
Cycle 5/9	1756	1802
Cycle 6/9	1749	1787
Cycle 7/9	1739	1782
Cycle 8/9	1723	1772	
Cycle 9/9	1708	1758	
Break-In	1802	1856


Instead of improving the cells I lost 10%. The capacity dropped with every cycle.
Measuring the ICV I get values between 1.7 & 1.8 - finally not that bad. I always thought that older crap cells will have values of 2 or higher. Isn't that so?

How do old end-of-life cells behave if you treated them well? Will the internal resistance also increase or will only the capacity drop?
If I want to judge the cells then I have at the moment 3 criteria:
- capacity
- self-discharging
- ICV (internal resistance) which seems to be connected to the voltage under load (the higher the ICV the lower U while discharging). Is this true?


----------



## Mr Happy

DT 123 said:


> Instead of improving the cells I lost 10%. The capacity dropped with every cycle.
> Measuring the ICV I get values between 1.7 & 1.8 - finally not that bad. I always thought that older crap cells will have values of 2 or higher. Isn't that so?
> 
> How do old end-of-life cells behave if you treated them well? Will the internal resistance also increase or will only the capacity drop?
> If I want to judge the cells then I have at the moment 3 criteria:
> - capacity
> - self-discharging
> - ICV (internal resistance) which seems to be connected to the voltage under load (the higher the ICV the lower U while discharging). Is this true?



It is not to be expected that repeated cycling of cells will improve them, only recover them from poor condition. Once cells have been recovered, they then enter the normal wear and tear cycle in which each cycle uses up a bit more of the battery and brings it closer to the end of its life.

There is no way to say what the ICV of any particular cell will be. It depends entirely on the specific cell.

Usually the internal resistance of cells will increase as they age and the capacity will drop. Both things are signs of cells wearing out.

Yes, the internal resistance of a cell is directly connected to the voltage under load. The higher the internal resistance the lower the voltage.

Since the capacity of your cells is going down so measurably with each cycle it seems they are really almost used up. They are at 68% of their label capacity which is rather low.


----------



## SilverFox

Hello DT 123,

Crap cells are a very interesting study. Some behave just like you are seeing. I think Mr Happy hit it on the head. The internal resistance is only part of the equation. When the electrolyte is compromised, or the electrodes dried out, the capacity just seems to fall off.

I recycle cells when their capacity drops below 80% of their initial capacity. Others keep using cells as long as they hold any charge at all. 

I have some NiMh cells from 2005 that are still at 85% of their initial capacity. I keep thinking it is time to retire them, but they keep on working. I take very good care of them and that care seems to result in long life and good performance.

Tom


----------



## N162E

SilverFox said:


> Hello DT 123,I recycle cells when their capacity drops below 80% of their initial capacity. Others keep using cells as long as they hold any charge at all.
> Tom


+1


----------



## finfin

I wanted to consult the sages and determine what action to take on cells that show discharge capacities that are 60-70 percent of the manufacturers label? Should I continue to refresh (with a discharge in between) or move straight into a Break-in mode? These are cells that have been in service for a few years with usually nothing more than dropping them in the charger and walking away. These particular cells are 750 mAh and 900 mAh AAA cells. After a couple of refreshes I am seeing about a 4 percent (of labeled capacity) increase for each cycle.


----------



## finfin

Sorry for reposting, but I could not see where to subscribe to this thread without reposting.


----------



## finfin

Sorry for reposting but I needed to subscribe to the thread. Then there was some sort of problem. Don't know how many of these posted.

Hmmm. Can't delete these.


----------



## SilverFox

Hello Finfin,

Welcome to CPF.

If you see improvement on multiple Break-In runs, you can keep running the Break-In function. It has the best chance to recover lost performance.

Tom


----------



## N162E

finfin said:


> I wanted to consult the sages and determine what action to take on cells that show discharge capacities that are 60-70 percent of the manufacturers label?


Time for new ones. They have served you well and paid for themselves many times over. If you keep them they may get mixed in with newer cells and degrade run times of your lights or other battery operated goodies.


----------



## N162E

Delete


----------



## N162E

Delete


----------



## shelm

Hi, is it possible to *discharge Alkalines* (cheap 1.5V AA, from the supermarket) on the C9000, and does this make sense at all?

Which *discharge rate* should i choose?

We certainly dont want to harm or damage the C9000 by doing so. Thanks for some thoughts!


----------



## finfin

Why not just put them in a flashlight to discharge them?
Why discharge them at all?


----------



## uk_caver

finfin said:


> Why discharge them at all?


It can be interesting to find out the capacity (and cross-cell capacity consistency) of cheap cells.


----------



## Mr Happy

shelm said:


> Hi, is it possible to *discharge Alkalines* (cheap 1.5V AA, from the supermarket) on the C9000, and does this make sense at all?
> 
> Which *discharge rate* should i choose?
> 
> We certainly dont want to harm or damage the C9000 by doing so. Thanks for some thoughts!



You can, but it would be best to choose a low discharge rate like 100 mA. Alkaline batteries don't respond well to high discharge rates and they will give you very poor capacity results.


----------



## shelm

thanks, i will use this setting to measure the capacity of my cheap Alkalines (and to compare Alkalines from different noname brands from different supermarkets).

it's an easy guess that -100 mA is still too high of a discharge rate for Alkalines but whaddya gonna do?, our C9000 cannot go lower than this! 

EDIT: completed. The cell has an "available capacity" of 1913mAh, was discharged to *0.90V* (C9000 display during the discharge near the end) and has now an offline voltage of *1.21V* (C9000 display after the "DONE" indicator). time for completion 21+ hrs. My battery tester indicates that the cell is still in the "green area", which means that there is considerable capacity left. Reinserting the cell in the C9000 gives a another discharge round: the available capacity is displayed as 2mAh lol, and voltage as 1.21V.

i come to the conclusion that the C9000 is *not* capable of FULLY discharging an Alkaline cell.


----------



## uk_caver

Mr Happy said:


> You can, but it would be best to choose a low discharge rate like 100 mA. Alkaline batteries don't respond well to high discharge rates and they will give you very poor capacity results.


As more information for our potential tester, I believe the _*rough*_ guide is that a good alkaline AA (regular Duracell, etc) is about 2700-2800mAh if discharged at low currents, but only ~2/3 of that (1800mAh) if discharged at 0.5A, and ~1/3 (900mAh) at 1A discharge.

I found some cheap cells over here (£0.50/4-pack, which is definitely cheap for the UK) which seem to have about 2/3 the capacity of Duracells at the loads I was interested in. The best price I could find on Duracells/Procells in medium quantity was a little over twice the price per cell.


----------



## shadowjk

Yes, you can do discharge tests on Maha C-9000. Don't try it on Lacross BC-700/BC-900/etc though, because it switches to charge mode immediately after a discharge, which is just asking for leaking alkalines.


----------



## czAtlantis

Discharging cells with higer internal resistance (Alkaline cells/older ni-mh cels) will get bad results with Maha - it is not discharging 100mA but 1A pulse and pause, pulse, pause...don't know when it measures the voltage but as i tried with older ni-mh cells, Maha showed only few mAh. When I tried to discharge the cell on regulated power supply with constant current (the same current as configured on Maha) it showed real capacity (around 1Ah). I hate Maha charger for doing this. Why is the current pulsed? Is it too expensive to make variable current source?


----------



## shelm

-100 mA is still a high discharge rate. Thanks for the answer. Am discharging now an already empty Alkaline.. 
Is fun!!


----------



## AlphaZen

I believe I read on here that the alkalines will show DONE, and then once you let them rest for a bit, they will discharge some more. If this is the case, you may have to do a few discharges on the same cells to get a true reading of capacity.


----------



## Wrend

Same is true of NiMH cells to a degree too.

There isn't a true or real capacity (since it's somewhat relative to other factors) as much as just an effective capacity.

I'm not sure what the standards for measuring capacity on alkaline cells are, but that would be the way to go if you want to measure relative capacity.

Or just compare them to the NiMH cells. Use the same testing standards to see how they compare, if that's what you're trying to do.


----------



## DT 123

It is said that LSD cells are losing in the first month about 15% of their capacity and after that about 1% per month. (the exact values are not that important for my question). 
I would like to know whether somebody tested already whether that capacity loss is of the real capacity or the labeled on (eg 1900 or 2000 for the eneloop).
The reason for asking - if i charge LSD cells and I know that I will use them only in 2-3 months. Does it make a difference then whether I let the C-9000 perform the 2 hour topping off or not.

From the logical point I can only believe that the 15% capacity 'loss' will be for the max capacity or the 15% is only a value for it. 
Otherwise I have no idea what whould happen in the following scenario:
Charge an eneloop full and add every month only 100mAH (which is only 5% of the total capacity).
Will the eneloop have after a year no capacity anymore or will the 15% loss in the first month only be triggered by a 'full' (whatever this exactly means) charging?


----------



## Wrend

First off, it's about 15% for the first year. It's meassured from a full charge. It might self discharge the remaining capacity a little slower if it isn't as fully charged, but then there is still less charged capacity to work with.

If you're charging multiple cells, I would let them go through the top off portion of the charge to help balance them at a more fully charged state, then not worry about charging them again until after you use them.

If it's been several months or more, you could cycle the cells to help keep their performance high.


----------



## JudasD

Once the charger says DONE (from charge mode). Is there any indication that the charger is in topoff or trickle or is time your only indicator?
I tried to search for this answer in the thread but was not able to find the answer. Please forgive me if it has already been addressed. 

Thanks,
JD


----------



## Wrend

The only other way to check is by cell voltage. It should start to drop off a little more when it's really done, even though there is a very small maintenance charge after the top off charge.

I just note the time and give them about 5 hours total when charging at 0.5C/h.

If you leave them on longer, it shouldn't be a problem, though I wouldn't leave them on indefinitely.


----------



## finfin

Back when my daughter was in grade school we did a science fair project on HD AA batteries. We set up an old PLC to record voltage at even intervals and plotted them. We calculated the area under the curve as mAh and tested several different batteries. We finally plotted mAh vs money spent and found the cheapest (Dollar General) were always the best, and usually were just as good mAh.


----------



## Wrend

Calculus for grade school is pretty ambitious. Then again, average voltage would be a fairly straightforward and accurate way to go.

Technically you would want current rate and time for mAh.

With voltage and a controlled constant current rate and time you'd get energy in mWh. But that is a good way of comparing cells. Better than mAh alone.

Of course with rechargeable cells these days, there isn't really a contest with the primary cells. For example 1 AA Eneloop is approximately equal to 1000 name brand alkaline AA cells in cumulative lifetime capacity potential.


----------



## finfin

Yes, that is why we limited the test to HD batteries. (apples to apples) Also the voltage curve and current curve are the same (units aside) with a constant load, aren't they?


----------



## Mr Happy

Wrend said:


> Calculus for grade school is pretty ambitious.



Of course it's not! 

One of the main reasons children think mathematics is hard is because nobody explains to them what it means and how it applies to the real world. A child of 10 should easily be able to understand why adding up the area under a curve leads to a useful number. If they get that concept in 5th grade they will find integration to be child's play in 11th grade.

Please don't support the dumbing down of mathematics teaching in schools. It's already far worse than it should be.


----------



## Mr Happy

Grade school advanced mathematics:

http://www.youtube.com/watch?v=DK5Z709J2eo


----------



## Wrend

finfin said:


> ...



I'm not an electrician, but I tend to think of load as being the power in watts, or current. People seem to use the term to mean different things. :shrug:

But yes, if the resistance stays the same and the voltage drops (like when a cell starts to run low), then the current will drop too.

I was just being overly picky I guess. The main reason I point it out though is because you could measure the current rate and time of 1 AA cell, or 2 AA cells in series, and get the same capacity measurement, even though the 2 AA cells would hold twice as much energy. And then not all the AA cells have the same voltage characteristics as each other.



Mr Happy said:


> ...



Well, compared to the normal it's ambitious. I'm not saying ambition is a bad thing. I kind of meant it as a compliment.


----------



## DT 123

Wrend said:


> First off, it's about 15% for the first year.


I am pretty sure that i read that the most of the loss will be in the first month. I am still looking for the source. And I measure for eneloops one months after a 2000+ break-in only a capacity of ~1800 mAh.
And some other (non-eneloop) LSD cells have a higher self-discharge rate.

But i have never tested how cells behave which i charged only to 50% of their capacity.


----------



## Wrend

1800mAh is about 90% charged.

Eneloops claim to retain 85% capacity after one year, but yes, they do self discharge more initially. And yes, they most likely will not self discharge as much initially if they are not charged as much, though they will likely still discharge more initially than later.

However, I have not personally tested the self discharge rate of Eneloops with any real precision.

Here is a link to some tests Tom "SilverFox" did on the first generation of Eneloops: http://www.candlepowerforums.com/vb/showthread.php?149804-Eneloop-Self-Discharge-study

In general I would say that the fuller you charge them, the fuller they'll be charged later, but no, it's not vital that you top off the cells after a charge. I was recommending it mostly so that the cells are more in balance with each other.


----------



## Burgess

to Mr. Happy --


*Thank you very much* for the YouTube link.


That young lady is certainly Quite Awesome !


:wow:


----------



## jayflash

Sorry if this has been answered, but there's so much info to wade through. Given that the Break-In cycle first applies a charge, might it be better to first discharge a cell at a low rate before running the long "forming" cycle? If a cell is already fully charged, how much benefit will come from a 16 hour charge? Even the low rate used is still a long overcharge. By first using a .1 or .2C discharge, wouldn't that add to the conditioning more than a possible long overcharge? Thanks!


----------



## SilverFox

Hello Jayflash,

I believe that recommendation is buried in this thread... somewhere.

Tom


----------



## Wrend

I think the break in function of the charger was designed more around standard NiMH cells and less so around the low self discharge ones, since it doesn't discharge them first.

I discharge my new Eneloop cells at 100mA on the charger before doing the break in. For the Eneloops, I set the AA capacity to 1900mAh and the AAA capacity to 800mAh.

You don't have to discharge them that slowly. I prefer to do it that way because I think it helps refresh the cells a little more.

But, yes, I would recommend discharging your low self discharge cells (or cells that aren't near "empty") on the C9000 before doing a break in on them.


----------



## jalyst

I've had 4x 1900(min)mAh AA Eneloops in break-in mode for about 29hrs now.
Is this normal? I was expecting it to have finished by now, but it's still going!!
Both pairs had been used once from their pre-charged state, until they were flat.
They were roughly 6mth old (I've no real idea how old TBH) before I used them.


----------



## AlphaZen

jalyst said:


> I've had 4x 1900(min)mAh AA Eneloops in break-in mode for about 29hrs now.
> Is this normal? I was expecting it to have finished by now, but it's still going!!
> Both pairs had been used once from their pre-charged state, until they were flat.
> They were roughly 6mth old (I've no real idea how old TBH) before I used them.


The break-in requires 39-45 hours to complete.


----------



## jalyst

Thanks for confirming that....
I noticed it was charging them to well past their 2000mAH max too.
Then taking them way back down, then up etc. 
Is it normal for it to take them above their capacity?


----------



## AlphaZen

jalyst said:


> Thanks for confirming that....
> I noticed it was charging them to well past their 2000mAH max too.
> Then taking them way back down, then up etc.
> Is it normal for it to take them above their capacity?


Yes. It uses the capacity you enter to determine "C" for the charge rate. It then charges for 16 hours at .1C, rests, discharges at .2C, rests, and then charges again at .1C. So, if you entered 1900 as the capacity, it would charge at ~ 190mAh for 16 hours, rest, discharge at 380mAh for 16 hours, rest, and charge again at 190mAh for 16 hours. During this process it will usually "overcharge" the cell well above the capacity, but at such a low rate it is not harmful to the cell. The need to do this whole process on Eneloops is debatable, as referenced by Wrend in his post above, #923.


----------



## 45/70

jayflash said:


> ......Given that the Break-In cycle first applies a charge, might it be better to first discharge a cell at a low rate before running the long "forming" cycle?



Hi jay. As Tom mentioned, this question is often asked in many of these C9000 threads.

I joined the eneloop club a bit later (a year or so?) than many, as I already had quite a few "traditional" NiMh cells, when the LSD cells came out.

I had been playing, er um, "working" with many conventional NiMh and NiCd cells before I bought my first eneloops. From the results I had obtained from this previous experience, I decided to do a slow discharge at 100mA, before starting the "break-in" of my new eneloops. These cells were the same general date of manufacture (8/06) as others had been testing.

My C9000 break-in capacities utilizing a 100mA discharge first, resulted in capacities 50-100mAh higher than those members who simply put the eneloops in without doing any kind of discharge before the break-in.

As Wrend pointed out, the slower a cell is discharged, the more discharged the cell will actually be. This helps to reactivate any of the chemicals within the cell that otherwise would be missed, during the forming charge. I attribute this being why my average capacities were a bit higher than other members, who did not discharge the cells first.

Additionally, as Tom and others noticed, LSD cells don't seem to take as kindly to overcharging, as traditional NiMh cells. While extensive proof of this may not exist it IMO, is another reason to do some sort of discharge before running the break-in cycle, when breaking in LSD cells with the C9000.

Dave


----------



## jayflash

Thanks, Wrend & 45/70, your method is what I've actually been following. I've "enough"  LSD cells that I could keep the charger on almost constantly just to give them an infrequent break-in cycle, along with normal charging duties. 

Until recently buying the Maha 9000, I'd use a LaCrosse BC - 900 to do an occasional 100mA discharge. I'd use the discharge/refresh and try to catch the cells before they'd begin recharging so I could use a one amp charge rate after. Too bad the BC-900 didn't just stop charging or have a rest period. The Maha's ability to discharge only and provide the capacity is useful for me. I enjoy the flexibility of the Maha and will use the LaCrosse for batch work.

In the four years of using "Duraloops" they've retained about 1800 mA capacity without a genuine EIC break-in cycle. Apparently, the occasional slow discharge and subsequent .5C charges have been sufficient. I'm trying the Maha "EIC" cycle on some old NiMh and NiCd cells just to keep the charger busy.

It's interesting that these two chargers: the 900 & 9000, have plenty of ventilation and the Maha 808 & Titanium MD - 3000 have nothing.


----------



## jalyst

AlphaZen said:


> Yes. It uses the capacity you enter to determine "C" for the charge rate. It then charges for 16 hours at .1C, rests, discharges at .2C, rests, and then charges again at .1C. So, if you entered 1900 as the capacity, it would charge at ~ 190mAh for 16 hours, rest, discharge at 380mAh for 16 hours, rest, and charge again at 190mAh for 16 hours. During this process it will usually "overcharge" the cell well above the capacity, but at such a low rate it is not harmful to the cell. The need to do this whole process on Eneloops is debatable, as referenced by Wrend in his post above, #923.



Thanks for the refresher, I knew all this once-upon-a-time, but forgot it all! 

Ah, I hadn't seen Wrend's post, interesting...
Well luckily I had already flattened both my pairs before doing the break-in.
But I must remember to do a slow discharge on any new LSD's next time!

The break-in finished ages ago now, but I haven't needed the batteries yet.
2004, 2010, 2016, & 1975mAh is the final capacity of them all, so one has notably less capacity for some reason?
Hopefully it's fine that they all remain sitting in the charger for a bit longer?

I wonder how much the most recent C9000's have changed (if at all) compared to mine?
I mean either hardware & or firmware wise. My model no = 0K0BA.

Cheers!


----------



## jalyst

^ *bump* Anyone?

Thank-you.


----------



## Wrend

> 2004, 2010, 2016, & 1975mAh is the final capacity of them all, so one has notably less capacity for some reason?



Those are all within the normal expected resultants. Average is around 1987mAh or so.



> Hopefully it's fine that they all remain sitting in the charger for a bit longer?



I wouldn't leave them on the charger, since there isn't any need to.



> I wonder how much the most recent C9000's have changed (if at all) compared to mine?
> I mean either hardware & or firmware wise. My model no = 0K0BA.



I don't think the main firmware and hardware has changed at all since then. The newer C9000 I got about a month ago seems to have a slightly different power supply.


----------



## jalyst

Wrend said:


> I wouldn't leave them on the charger, since there isn't any need to.



Does it hurt to leave them there? I don't think it's doing anything to them anymore.
Break-in mode's complete it's just cycling through the slots, & showing each batteries voltage/capacity etc.
I've removed them anyway, but just curious....



> I don't think the main firmware and hardware has changed at all since then.
> The newer C9000 I got about a month ago seems to have a slightly different power supply.



What month/year does my code represent? I forget how you read it.
So slightly different PSU since my model, thanks for confirming.

Thank-you!


----------



## SilverFox

Hello Jalyst,

There is a small trickle charge applied after the main charge and top off have completed. With normal NiMh cells, this is designed to offset the normal self discharge rate of the cell. However, with low self discharge cells it may create a problem because of the constant overcharge.

In general, chargers are to charge cells - not to store them.

Tom


----------



## jalyst

^Thanks for answering my 1st question silverfox!


----------



## Wrend

> My model no = 0K0BA.



K for 11 (2011), and B for 2 (February).



> Does it hurt to leave them there?



There is also a chance that you could lose power to the charger and that if the power comes back on it will charge the cells at the default 1000mA. That probably wouldn't be too much of an issue since the cells should stop once they reach 1.48V, but still not ideal.



> So slightly different PSU since my model, thanks for confirming.



Sorry I wasn't more specific. I meant that it was different from my other C9000. I'm not sure if the slightly different power supplies are model specific or not.

My older model's code is OKODA, and the newer one is OKOEA.


----------



## Russel

AlphaZen said:


> Yes. It uses the capacity you enter to determine "C" for the charge rate. It then charges for 16 hours at .1C, rests, discharges at .2C, rests, and then charges again at .1C. So, if you entered 1900 as the capacity, it would charge at ~ 190mAh for 16 hours, rest, discharge at 380mAh for 16 hours, rest, and charge again at 190mAh for 16 hours. During this process it will usually "overcharge" the cell well above the capacity, but at such a low rate it is not harmful to the cell. The need to do this whole process on Eneloops is debatable, as referenced by Wrend in his post above, #923.



Charging at lower current rates are not as efficient. If you look at the Eneloop spec sheet Sanyo recommends 200mA for 16 hours, or for fast charging, 2000mA for 1.1 hours. Clearly, fast charging is more efficient. Charging NiMH cells for at 0.1C for 16 hours is a common charging standard, not considered overcharging.

Running a fully charged Eneloop AA cell throught a MH-C9000 break in cycle could be considered overcharging (during the first charge cycle), but is generally not harmfull as you stated. But, charging a fully depleted Eneloop AA cell at 200mA for 16 hours is not.


----------



## Wrend

It is a standardized process not specific to Eneloops.

If you're aim is just to fully charge your AA Eneloop cells, charging at 0.1C/h will accomplish this in about 13 to 14 hours.

The break in cycle does apply more than a full charge's worth to the Eneloop cells while taking into account their charging efficiency.


----------



## Russel

Wrend said:


> [...]If you're aim is just to fully charge your AA Eneloop cells, charging at 0.1C/h will accomplish this in about 12 to 14 hours.[...]



Then why does Sanyo recommend 0.1C for 16 hours?


----------



## Wrend

double post


----------



## Wrend

Because it is the standard practice. It may also be that their charging efficiency towards the end of their useful lives isn't as good.

I updated my post to 13 to 14 hours which should be more accurate.

At the full 16 hours you might get them to hold a few more mAh worth of capacity fresh off the charger, but I wouldn't really consider that a significant amount relative to their stored capacity.

Of course at the 16 hours you know for sure that they're full, and can have a value to compare against.

...

Higher charging efficiency at faster rates might be in part because of the higher cell temperatures at these rates. I have not tested this specifically, and can't say for sure one way or the other.


----------



## jalyst

Thanks for the final answers Wrend!


----------



## uk_caver

Wrend said:


> Of course at the 16 hours you know for sure that they're full, and can have a value to compare against.


That makes sense.

If a cell is _conservatively_ marked as '2000mAh', potentially it might have a somewhat higher capacity, and if someone is trying to measure the capacity, it makes sense to do a dumb charge which will definitely fully charge the cell unless the marking is ridiculously conservative.


----------



## shelm

Question (faq):
What's the reason that the C9000 refuses to charge "HIGH" cells? (Why wouldnt the designers let the C9000 charge such cells?)

During the night my old mobile phone (3x AAA) resurrected 13 months young cheapish NiMH's cells (BTY 1000, see ebay/google) from death (~0.0V, ~0.0V, 0.6V) to 3x 1.29V. I dont know about capacity (because the C9000 wouldnt accept these BTY cells), though.

Afaik the BC-700 doesnt have a problem with such high resistance cells.

So maybe this is one of the few disadvantages of the otherwise very nice C9000: *it doesnt charge "HIGH" cells*!, and not even the ones which i had bought 13 months ago brand-new off ebay (buyincoinsDOTcom seller from China).

a little disappointing.


----------



## uk_caver

One reason for rejecting 'HIGH' cells (as even some very cheap smart chargers do) could be to avoid charging alkaline cells put in by mistake, as well as to indicate unignorably when rechargeable cells may be on their last legs.

I'd agree that having an _override_ of the HIGH function on a C9000 might be occasionally useful, though possibly only to a small number of people.

Personally, I have an old dumb charger I can stick cells like that in.


----------



## shelm

uk_caver said:


> One reason for rejecting 'HIGH' cells (as even some very cheap smart chargers do) could be to avoid charging alkaline cells put in by mistake, as well as to indicate unignorably when rechargeable cells may be on their last legs.
> 
> I'd agree that having an _override_ of the HIGH function on a C9000 might be occasionally useful, though possibly only to a small number of people.
> 
> Personally, I have an old dumb charger I can stick cells like that in.


The C9000 is smart enough to recognize _all _alkalines (from _all and any_ parts of the world) as HIGH? Maybe someone can talk figures? (_What is the HIGH range of alkalines and where does the C9000 draw the line? And what is the value for Eneloops and why are 1.0yr old NiMH's already rejected as HIGH? ... lots of questions, i am just wondering_) 

Yes, i would override the HIGH function too if operation of the C9000 is still safe.

I think i like dumb chargers now


----------



## shadowjk

All the cells rejected as "HIGH" by my C-9000 are ones that heat up worryingly much in BC-900, and ones that I can even tell a difference in brightness vs eneloop in fully regulated AA lights.. I still charge them in BC-900, of course, until they (or the charger) starts making small creaking noises from the heat expansion...


----------



## shelm

shadowjk said:


> All the cells rejected as "HIGH" by my C-9000 are ones that *heat up worryingly much in BC-900*, and ones that I can even tell a difference in brightness vs eneloop in fully regulated AA lights.. I still charge them in BC-900, of course, until they (or the charger) starts making small creaking noises from the *heat expansion*...


oh i like this explanation (which doesnt distinguish between alkalines and *12months young* ebay NiMH's like mine). it is true that my ebay NiMH's are very warm when i take them out of the mobile phone (which acts as a dumb slow charger).
preventing heat buildup in the cells could be a good designer's reason to let HIGH cells reject, no matter if they are alkalines or NiMH's.

Then again, if an apparatus is built rugged enough, it would withstand heat buildup (in the cells or in the apparatus itself), wouldnt it?

I read about "melting BC-900's" .. but that was a general problem (incl Eneloop charging).


----------



## Mike89

12 months old from ebay doesn't mean they are 12 months old. They could be 12 years old. In my experience if the C9000 shows high, the batteries are bad. Maybe not dead dead but capacity is shot to hell, won't charge right, time to get rid of them. Putting those into a dumb charger is like keeping someone on life support to an agonizing life when the plug needs to be pulled and let go. The C9000 is pretty dependable to bring batteries back from the dead when they are still salvageable. Sometimes the battery is no good no matter what you do.


----------



## SilverFox

Hello Shelm,

A cell with higher internal resistance will heat up more during charging. The C9000 does a quick check to determine the internal resistance of the cell. If the internal resistance is high, it gives you the HIGH display.

Since the C9000 is capable of charging at 2 amps, it is a little more picky about this than other chargers that can not charge at this high a rate.

High internal resistance means that when a load is applied the cell voltage drops to a lower value. When this happens, the capacity is also reduced. All in all you end up with sub par performance from your cells.

I call these cells "CRAP cells" and recycle them and move on. 

Other people have fond memories of their cells and prefer to take the stand that as long as you can measure a voltage on the cell, it is good for something. 

Tom


----------



## czAtlantis

Mike89: +1, I had number of cells showing "high" but with quite good capacity at lower rates. But got rid of them because they couldn't deliver higher current - short-circuit current was only at 2-3A. So they were fine in wireless keyboard or mouse but because they were not LSD they didn't last very long. I bought bunch of Eneloops and replaced them all in all devices.


----------



## shelm

SilverFox said:


> Since the C9000 is capable of *charging at 2 amps, it is a little more picky* about this than other chargers that can not charge at this high a rate.
> 
> ...
> 
> Other people have *fond memories* of their cells and prefer to take the stand that as long as you can measure a voltage on the cell, it is good for something.


Hello SilverFox,
thanks! I like this explanation a lot. Makes very good sense to me. So basically the designers implemented this as "overheat protection in favor of the HIGH cell" which could occur especially at higher charge rates. And the heat of the HIGH cell could also effect negatively the neighboring cell's charge/discharge process or the apparatus itself, right? i guess so then.

True, i would be concerned about my warm BYC 1000 cells (then hot!) if they were charged with higher currents than what is supplied in mobile phone devices.

Thanks all!! I have gained a better logical understanding of our C9000 
Very helpful thread, very helpful people.


----------



## InHisName

There is a number to track to indicate how close the cell is to HIGH. When first inserted a AAA might show 1.45 v for a new eneloop before settling down to 1.24 or such. As the cell ages and is used / abused etc. it will creep upward as you cycle it many times. When it approaches 1.9x and more, you are nearing the end. HIGH occurs somewhere around 2.10-2.15 I once saw 2.14 and it charged. Other times I have seen 2.11 and it replied HIGH.

If you REALLY want to charge that HIGH cell this time in your C9000, start with a nearly new cell and set up for current to charge the HIGH one. Wait until it displays all numbers 2x, then after MA displays and MIN is to start, QUICKLY remove the new one and insert the HIGH cell in its place FAST. It sometimes is fooled and at this point is NOT checking cell impedance anymore. You'll notice the v level display will be somewhat different because it is a different cell. I find cells do not get warm if charged at 0.5c. 

For low to med current needs it still is ok. Just a bit more trouble then before. 

If a HIGH cell is used many more cycles, you may discover the MOST HIGH mode. This shows as starting to charge a cell and it resets to prompting for battery settings ! This v rating is at about 2.85 for my AAA cells. I hve to guess that as it just blanks out and starts again. Those cells are even junkier than junk. Not even good for medium current needs and can only be used for lowest drain usages (remotes, clocks, etc.)

My Duraloops that I bought Oct 08 have all gone HIGH now. They started as they neared 100 cycles and by 120 all 12 cells were HIGH. MY 12 AAA NexCells purchased Jul 08 and lasted 70-95 cycles before going HIGH. All used in family radio 'walkie-talkie' with rarely used transmits. Approx 17-24ma in stand by for 3-4 10 hour nights. The 'half used' indicator was probably after a cell reversal occured, so I may have a lot of that kind of abuse.


----------



## Mike89

I've played around with recharges for some time now. I'm done with my "tweaking" days where I'm just sitting in front of the charger trying to be a battery scientist tweaking my batteries for no other reason than to tweak. Now I just want the batteries to work like new and give me top performance. Once I get a "High", they are history. "Served me well dude but it's time for you to go". I'm not going to fiddle around trying to find a dumb charger to end up putting them in a clock or something where even then it's going to last a month instead of a year. Not worth my time and effort trying to keep up with failing batteries all over the place in my devices. Of course this is just what a tweaker would like to do, been there done that. But, hey that's just me. The C9000 is doing what it's supposed to be doing.


----------



## ChrisGarrett

Mike89 said:


> I've played around with recharges for some time now. I'm done with my "tweaking" days where I'm just sitting in front of the charger trying to be a battery scientist tweaking my batteries for no other reason than to tweak. Now I just want the batteries to work like new and give me top performance. Once I get a "High", they are history. "Served me well dude but it's time for you to go". I'm not going to fiddle around trying to find a dumb charger to end up putting them in a clock or something where even then it's going to last a month instead of a year. Not worth my time and effort trying to keep up with failing batteries all over the place in my devices. Of course this is just what a tweaker would like to do, been there done that. But, hey that's just me. The C9000 is doing what it's supposed to be doing.



I'm actually there, but only a month after starting. 

I've got some 6+ year old IC3 15 minute batteries that have been abused and while I've seemingly brought them back a bit, they're only at 60%+--good enough for my RF keyboard and mouse, but I think that I'm through with them--they're ready for the recycle bin.

I can agree that SilverFox's comment about 'getting attached' to older cells rings true. I've had these batteries for a while and they've served me well. Always hated having the KB go glitchy on me due to battery drain right in the middle of a post and those 15 minute charges were nice to have.

Oh well...I'm finishing up a final charge on a second (of three) quad of different LSD brands, which I'm putting away for a year and this 'fiddling' will be pretty much it, for me, for a while. I've got everything documented, so after Saturday, goodbye!

Chris


----------



## jalyst

If I chose refresh/analyze mode (l've used break-in on all my new sets now) 
How do I know what charge/discharge rate to set it at?
My Eneloop's are rated for 2000mAh (min 1900)... TY.


----------



## bbb74

jalyst said:


> If I chose refresh/analyze mode (l've used break-in on all my new sets now)
> How do I know what charge/discharge rate to set it at?
> My Eneloop's are rated for 2000mAh (min 1900)... TY.



Its been asked 10000 times before but for eneloop AA's 1000mA charge and 400mA discharge are fine (0.5C charge and 0.2C discharge).


----------



## jalyst

bbb74 said:


> Its been asked 10000 times before but for eneloop AA's 1000mA charge and 400mA discharge are fine (0.5C charge and 0.2C discharge).



Couldn't recall the 0.Xc rates, & it's not on the manual that comes with it, ta.


----------



## DT 123

I have some problems to understand the following. I have a set of 4 AAA Eneloop which I am using in a Babyphone. I charge them once a week. 



Code:


            #1    #2    #3    #4
        Charge    mAh    mAh    mAh    mAh

25.02.2012    400mA    646    639    621    632
04.03.2012    300mA    678    699    705    700
11.03.2012    300mA    485    502    511    503
23.03.2012    300mA    763    795    806    795
01.04.2012    300mA    595    614    615    620
09.04.2012    700mA    645    671    684    677
17.04.2012    300mA    662    687    698    695


If i dont look at the first result then I add to cell #3 always the most and to cell #1 always the fewest.
I know that the values are not differing too much - but which cell is the better one and why?


----------



## SilverFox

Hello Dt 123,

Along with variations from cell to cell, there are also variations from slot to slot. Each slot is separate and an effort is made to bring them close, but there still are variations.

To continue with your testing, you would exchange places between cell 1 and cell 3 and see if the differences follow the cell or the charging slot.

Another thing to keep in mind that the amount of charge that goes into the cell may vary. The important number is the amount of capacity that comes out of the cell during a discharge. Your chart seems to indicate that you are reviewing the amount of charge put into the cells. If that is the case, do a discharge and look at those numbers.

Tom


----------



## bbb74

Some (many?) C9000's will report a lower amount charged into Slot 1 than the other 3 slots. Both of my C9000's (with different batch numbers) do this. On a larger amount charged in, the difference can be up to 100mAh difference between slot1 and the other slots. A number of people have noticed this (there is some discussion of it on the whirlpool best charger forum).


----------



## DT 123

Before I used the cells I did a Break-In with these cells (and put them together as one set):



Code:


11.01.2012   787    791    794    792


I was only wondering - shouldn't the cells in real life (Babyphone) discharge all at the same rate? And if they do so - shouldn't i expect to get the same amount charged in for all cells? Theoretically at least. Or cannot I judge these results at all since the C9000 stops the standard charge too early and the top off will equal it again? (that's the reason why you asked for discharging results)
I always had cell #1 in slot #1 (except for break-in). So i will try to vary the slots the next time.


----------



## bbb74

Theoretically yes. A breakin terminates by time so breakin values should be pretty accurate. But charge cycles terminate on temperature and voltage, and as I was saying, many people have noticed that slot 1 generally charges in less than the other slots, even if you move the batteries around. I've experimented with 4 different brands of batteries, with 4 cells of each type, discharging all of them identical amounts (based on time with a resistor) and slot 1 was always consistently "out".

I often leave my cells in for the 2 hour topup charge so it all gets evened out in the end anyway.


----------



## aagf

I've read this thread end to end over the last few days and now feel comfortable having bought a bunch of Eneloops and the C9000. All my questions were answered (along with a few I hadn't thought of yet!), so I just wanted to pass along my thanks to all those who have contributed, and especially to those who have patiently responded to the same old repeated questions - you have more tolerance than I do. 

What I found to be useful was to create a Docs to Go sheet on my tab, and cut/paste especially informative info into it - gives me a fast "go to" when my last remaining brain cell loses charge ...

Thanks again!

Andy

P.S. My C9000's date code is 0K01A (bought about a week ago).


----------



## JudasD

The C9000 is a very nice piece of equipment to own. I also own a fairly expensive hobby charger, but the C9000 still sees a lot of use. You just can't beat the separate charging channels AND the break-in/analyze cycles for only 50 bux.

JD


----------



## TakeTheActive

DT 123 said:


> *I have some problems to understand the following.* I have a set of 4 AAA Eneloop which I am using in a Babyphone. I charge them once a week...


Please run a '*Refresh/Analyze*' @ 400/200 and post the results.


----------



## TakeTheActive

bbb74 said:


> ...But *charge cycles terminate on temperature and voltage*...


Actually:
-DeltaV
Max Voltage
Max Temp
Max Time
But the C9000 is so gentle, with its Max Voltage set @ 1.47VDC, I believe that is the most used. AFAICT, I've never seen my C9000 terminate on Max Temp.


*TTA's NiMH/NiCD Battery Charger Specifications Thread: Maha MH-C9000*​


----------



## Mr Happy

DT 123 said:


> I was only wondering - shouldn't the cells in real life (Babyphone) discharge all at the same rate? And if they do so - shouldn't i expect to get the same amount charged in for all cells? Theoretically at least.


Theoretically at least, the answer would be yes. But there are all sorts of reasons why you may see slightly different numbers, depending on differences between cells, differences between slots in the charger, variations in temperature between slots, and so on. You are getting results that match within about 5% and that is fairly good accuracy for inexpensive equipment in uncontrolled conditions. If you were to do experiments in a physics laboratory with very expensive equipment and tightly controlled experimental conditions you could obtain more accuracy.


----------



## tobrien

so is the closest thing to the C9000 for li-ions a hobby charger?


----------



## 12smile

as a professional photographer I love this charger...I've used it for about 5 years and I just pop the cells in till 'done' I like having all the other capabilities but haven't had to use them yet. It's expensive compared to others but just buy it, if you need to reconditon cells you can 'read the manual'


----------



## TyJo

tobrien said:


> so is the closest thing to the C9000 for li-ions a hobby charger?


There is a charger out there that says it can do multiple chemistries but I would stay away, I don't trust it. I have the MH-C9000 for my Eneloops and a Pila for my 18650s and RCR123s, I've heard that cottenpicker chargers for li-ion are good as well.


----------



## DT 123

I asked in http://www.candlepowerforums.com/vb...continuation&p=3925926&viewfull=1#post3925926 about the differences i saw while charging.
Yesterday i used different slots of the charger and got totally different results:



Code:


			cell 1	cell 2	cell 3	cell 4
17.04.2012	300mA	662	687	698	695	(charegd in slots 1 2 3 4)
27.04.2012	300mA	803	804	777	792	(charegd in slots 4 3 1 2)


so the reason for the differences are the different slots which behave slightly different. I know that it is only the charging amount and that this doesnt say much. 
But earlier (with other chargers) i also used the quotient discharged / charged amount to judge the quality of a cell.


----------



## Wrend

The most accurate way to judge and compare the performance of a cell with the C9000 charger is to slowly discharge the cell on the C9000 then do a break in test on it. The capacity setting I use and recommend for AA Eneloops is 1900mAh and 800mAh for AAA Eneloops.

To top off the cells and help balance them at a more fully charged level while doing a normal charge, I recommend leaving them on the charger for at least 2 hours after the "done" message is displayed. This does not add to the listed mAh charged amount, but does continue to charge the cells at a reduced rate. I charge my AA Eneloops at the default 1A rate and the AAA Eneloops at 400mA, and leave them on the charger for a total of at least 5 hours. I am considering reducing the charge rate for the AA Eneloops to 700mA in hopes that it will more fully charge them and balance them, but I have not yet determined how balanced/imbalanced the AA cells are after a 1A charge and how much more balanced they would be at a 700mA charge. According to my testing, the 400mA charge rate for the AAA Eneloop cells does end with them being sufficiently balanced after the top off portion of the charge and does not overcharge them. In fact my AAA series sets of Eneloop cells are so well balanced that they are typically within 1mV of each other during their entire discharge in devices they're used in.

I think the charger port variations have more to do with the temperature of the charger in those areas (the first port being the coolest and the third being the warmest). I have considered putting a thin metal band across the charger behind the middle of where the cells sit to help even out and dissipate this temperature difference.


----------



## espresso

*Does C9000 perform top off during rest*

Just got this charger all the way from America as it's not available in my country (Amazon doesn't ship, Paypal doesn't work, communists seem not to have gone, etc). 
I was wondering if C9000 performs top off in cycle mode. I was observing the display closely and noticed that battery voltage during rest (in cycle mode) doesn't drop at all. As the matter of fact it's the same (1.41V) as the voltage on the rest of the batteries that are still being charged. So my conclusion is that the resting batteries must still receive some charge. Either that or the voltage displayed is incorrect. 

What does exactly happen during rest? If the batteries don't receive top off in cycle mode it means that they are not being fully charged.


----------



## gopajti

*Re: Does C9000 perform top off during rest*

Hello guys!

My MH-C9000 (0K0JA) recived few days ago, here my little review (in hungarian) with many pics. I like it.

http://elemlampa.blog.hu/2012/05/11/maha_powerex_mh_c9000


----------



## Ollifi

Hi!
Just received my Maha MH-C9000 charger yesterday. My previous charger was Tronic from Lidl, but I wanted some better charger so bought C9000. I have just couple of questions:
Now I'm charging new Eneloops with Break-In mode. In future, what charging rate and what discharging rate I should use with the normal programs (charge and discharge)?
If it's sometimes very hurry to get battery charged, what charging rate (mA) I should use? I think 2000mA maybe too high.
I have some not very good quality AA batteries bought from eBay. They say that mAh value is 2500 mAh, but I think it's not true. I have previously charged them with Lidl's Tronic charger, so they are not brand-new. But what mode should I use in C9000 one to determine real capacity of these Chinese batteries?
Thank you hopefully you could answer


----------



## czAtlantis

1) I am using 1000mA charge and 500mA discharge
2) Again I use 1000mA but I think they will withstand 2000mA without problems. Anyway - this charger charges at 2000mA on every setting - it just pulses these 2000mA so in average it will be the value you set. The same is with discharging but with 1000mA
3) discharge first, run break in (set capacity only to 2000mAh or less).


----------



## Ollifi

Thank you very much for answers. It's good to hear that 2000 mAh is OK for them, if used only rarely. If battery is not used to end, should I always discharge battery before charging? Or is it ok just to charge without discharging first? And yes I will try setting less than 2000mAh for the Chinese batteries.


----------



## SilverFox

Hello Ollifi,

Welcome to CPF.

The C9000 defaults to charging AA cells at 1000 mA. Many people use that and it works great. Eneloop cells can handle 2000 mA charging without problems, if you need them in a hurry.

When using the Break-In mode, you set the charge rate at what the capacity of the cell is. With Eneloop cells the capacity is close to 2000 mAh. You enter that and the Break-In charges at 200 mA, then discharges at 400 mA. Your other cells are labeled 2500 mAh. One way to check them is to do a Break-In and simply enter 2500 when choosing battery capacity. At the end of the process you can see how close they come to 2500 mAh. Another approach is to assume that the label is "optimistic" and adjust the capacity you enter in for the Break-In function a little lower. With 2500 mAh cells, a good value to use is 2200 mAh.

It is not necessary to do a complete discharge every time before charging. To keep cells vibrant a periodic full discharge helps, but it is not necessary for every charge cycle.

Tom


----------



## Ollifi

Thank you very much for your specific answer! I appericiate it much.  
EDIT:
Still I have more questions 

1. Is it ok to charge different brand batteries simultaneously? Even with different settings? (some break-in, some charge etc.)
2. What current should I use for AAA batteries? (I have VARTA, Tronic & Soshine AAA's, and their claimed capacity is 800-900 mAh.) Maybe I should run break-in for them too, even they have been already used and charged with the old Tronic charger?
3. Now charger shows about 2600 mAh for 2000 mAh Eneloops. How much is it usual to show larger number?


----------



## pinzmann

I been using the LaCross BC-700 lately which is actually my only smart charger for AA's. Is there any advantage to getting a C9000?


----------



## Ollifi

pinzmann said:


> I been using the LaCross BC-700 lately which is actually my only smart charger for AA's. Is there any advantage to getting a C9000?



AFAIK C9000 has better selection of charging currents (up to 2000 mA).


----------



## desirider

Hi Ollifi,

1. It is OK to charge different brand batteries in different modes simultaneously. The 4 channels are fully independent.
2. For AAA batteries, I would recommend 350-400mA. You can go higher if you are in a hurry, but pay attention to the cell temperature.
3. Charging capacity shown by C9000 is always higher than the discharge capacity. The charging process is not 100% percent efficient and some energy is lost as heat.

Hope that helps.

-Desirider.


----------



## Ollifi

Thank you desirider : ) 



*EDIT:* Still one more thing.
I have Chinese batteries bought from eBay. I charged them in my old charger and after charging I put them in digital camera. When I had taken some photos, and opened battery storage, one of the batteries was leaked. I throwed away that one, but saved the other three ones. So is it safely enough to charge the remaining ones in my new C9000 or do they leak and damage it?


I also think what's actually inside them. They are labeled "BTY" batteries. They feel very lightweight and their claimed capacity is 2500 mAh, which it cannot be. I measured some weights (all from AA batteries).


BTY rechargeable batteries 11 g, 10 g, 11 g
Eneloop rechargeable batteries 25 g, 26 g, 26 g, 26 g
Varta rechargeable batteries 28 g, 29 g, 28 g, 28 g
Aerocell not-rechargeable battery from Lidl 24 g


So the BTY ones are very light ones.


*EDIT2:* Now completed charging VARTA Ready2Use rechargeable batteries (VARTA number 56726). Their claimed capacity is 2300 mAh. My results in C9000's break-in:


2146 mAh, 1.42 v
2051 mAh, 1.39 v
2061 mAh, 1.40 v
2120 mAh, 1.42 v


BTW, Is there some other place posting charging results?


----------



## DT 123

I did a break-in to an older 1800mAh cell. The last break-in I did 5 months ago and the result was 1310 mAh. I wanted to know how much capacity was left and I discharged @400mA and retrieved 383 mAh.
So far so good. After the discharging I did a break-in which gave me a capacity of 172 mAh (!) as a result.

What is going on here? ICV is 1.80V. So the cell is not the best but for such an old cell still pretty good.

It is the first time that break-in seems to mess up something. Did anyone else had also similar problems already? It was a complete waste of 40 hours.


----------



## bbb74

DT 123 said:


> I did a break-in to an older 1800mAh cell. The last break-in I did 5 months ago and the result was 1310 mAh. I wanted to know how much capacity was left and I discharged @400mA and retrieved 383 mAh.
> So far so good. After the discharging I did a break-in which gave me a capacity of 172 mAh (!) as a result.
> 
> What is going on here? ICV is 1.80V. So the cell is not the best but for such an old cell still pretty good.
> 
> It is the first time that break-in seems to mess up something. Did anyone else had also similar problems already? It was a complete waste of 40 hours.



Probably high internal resistance means that when discharging at a pulsed 1A rate (with a lower duty cycle to reduce the overall rate to 0.1C) the battery voltage dropped to below 0.9v so the C9000 figured the battery was finished. If you want to still use the battery it may be viable in low current devices (eg. remotes etc etc).


----------



## DT 123

But this doesn't explain why discharging @400 mA seems to work well. After the break-in i discharged again and got 1327 mAh. While Break-In the discharging rate is 360 mAh. So the results shouldn't differ much.
Both - break-in and discharge will stop at 0.9V - isn't it so?


----------



## Mr Happy

Ollifi said:


> BTY rechargeable batteries 11 g, 10 g, 11 g
> Eneloop rechargeable batteries 25 g, 26 g, 26 g, 26 g
> Varta rechargeable batteries 28 g, 29 g, 28 g, 28 g
> Aerocell not-rechargeable battery from Lidl 24 g



Weighing the batteries like that was a good idea! The weight of a battery tells you how much "stuff" is inside it, and therefore gives you a good indication of its likely capacity.

Since they are so light, those BTY batteries are probably not more than 800 mAh (perhaps even 600 mAh).


----------



## czAtlantis

New BTY AA's "3000" mAh have around 800mAh and stabilizes at 500-550mAh after few cycles in Maha C9000, charged at 1A (I know it is too much) and discharged at 0.5A.


----------



## ferdz

Finally able to get myself a Maha Powerex MH-C9000 WizardOne Charger-Analyzer early today. It's a 0I0LA.

Before, I was inclined to get the latest La Crosse charger available locally (Philippines) but every time I was about to get one it's always out of stock from the very few sellers that have them here. Last week I bought a Sanyo MQN06 (w/ 2 AA Eneloops) and was searching for info on it and found myself here at CPF. I found out about the La Crosse meltdown issues from the previous model(s) which made me think twice about it. Eventually, the discussions here made me decide to get the MH-C9000 even though I just had a 1-week old MQN06. But I have no regrets because I got the charger much cheaper than if I get the BC-1000 which is about $30-$35 more from the one seller I found locally. Did not bother ordering online as the total cost (incl. shipping) will be more than getting it from some local retailers.

For my first go, I have 4 AA's in R&A (default settings) that had their labels peeled off from years of use that I totally forgot what their ratings are (R&A is the correct mode for this right? :sigh. I know one pair is a Sony (maybe 2500 or 2700 mah) and an EcoMax (an Eneloop clone locally available here). I'm still learning as I go as I'm still reading a lot of information about this charger. 

I'm also starting to look for some good flashlights and learn from the experts here. If there is anyone here from the Philippines can you point me where to get good flashlights?

Thanks!
Ferd'z


----------



## czAtlantis

I was curious if maha measures same capacity when powered from different voltages - I tested freshly opened pack of eneloops lite (because I know when I discharge them all 4 together their capacities are exactly the same +-5mAh) and discharged two at 14V input and two at 11V input - results were exactly same - within 5mAh.

Another test I performed - I again used freshly opened pack of eneloops (in this case AAA lite) and I tested if charging slots are independent - So in slot 1 was measured battery and in other slots were ohers battereis charging/discharging and there were some differences:
first battery (solo) - 397mAh
second battery (other slots charging):407mAh
third battery (other slots discharging):393mAh
fourth battery (other slots charging again) :407mAh

So charging bays are slightly affected by each other but it is not very significant. Charger and batteries were cooled by fan to exclude temperature effect.


----------



## march.brown

Probably a silly question , but is the Powerex C9000 charger the same as the Maha C9000 ? ... If not , what are the differences.

The ones advertised as the Maha are more expensive than the ones advertised as Powerex.
.


----------



## czAtlantis

I believe Powerex is company and Maha is product...anyway mine says "Powerex" on the front and "Maha" on the back


----------



## ferdz

march.brown said:


> Probably a silly question , but is the Powerex C9000 charger the same as the Maha C9000 ? ... If not , what are the differences.
> 
> The ones advertised as the Maha are more expensive than the ones advertised as Powerex.
> .



AFAIK, they are one and the same. The full name of the the product is Maha Powerex MH-C9000 WizardOne Charger-Analyzer. Maha is the name of the company (Maha Energy Corporation) and Powerex is one of its trademark brands/products. Maybe the more expensive ones you are seeing are those bundled with the 4x AA batteries (either a Powerex 2700mAh or Imedion 2400mAh).


----------



## 45/70

Yeah, although I belive it's actually the other way round. Maha Energy Corporation is the actual company, and Powerex is the product line. Anyway, yes my C9000's all have a Powerex badge on the front.

Dave


----------



## march.brown

Hi guys , thanks for all the help , I have just sent for one.

It was on Amazon UK , though it is apparently being sold be Mertrado Gmbh (Dandyshop) ... Not certain how long it will take to arrive in the UK from Germany though ... I originally intended to spend up to about £20 ('ish) , but this charger cost £39 ... About double what I originally intended.

I won't be able to tell "The Lady of the House" as she already thinks that three chargers are "two too many" ... But although one of them already has a discharge facility , none of them can calculate the battery capacity ... I want to put the cells in batches according to measured capacity ... I need a couple of spare matched sets of six AA's for my Wifes "Pure" radio ... Hence my vast expenditure (double the original) ... I know that is a pretty feeble excuse , but it's the best reason that I can think of at the moment and it *IS* for my Wifes radio ... I only bought this charger for *HER *needs !

74 years old and that is the best excuse I can think of !

I just hope the user manual is in English since the charger is coming from Germany !
.


----------



## apagogeas

march.brown said:


> ...I just hope the user manual is in English since the charger is coming from Germany !



Even if it was Chinese, you shouldn't worry about that. Everything you need to know and many more "secrets" are in CPF.


----------



## AlphaZen

Manual


----------



## ferdz

I'm not sure if I missed it or anything, but is there a way to determine the capacity of the battery without using R&A? Like plugging it in then pressing some buttons and it will show the status of the battery.


----------



## czAtlantis

You can't measure capacity without discharging battery - it is not like voltage which can be measured in one second...


----------



## SilverFox

Hello Ferdz,

Welcome to CPF.

The short answer is no.

In order to determine capacity a discharge is needed. You can put a cell into the charger and select discharge and then come back some time later and see how much was left in the cell. But you end up with a discharged cell.

The ZTS tester uses a look up table. They apply a load to the cell and compare the voltage of the cell to a look up table that they have put together by testing a variety of cells. Based upon their table, you can get some idea of how much is left in the cell. Some chargers also offer something like that giving results like charged, half charged, and discharged. The ZTS gives results as 10%, 20%, 40%, 60%, 80%, and 100%. If your cell matches the cells used to develop their look up table, you get reasonable results.

It is possible to put a cell into the Maha charger and then look at the voltage of the cell under a discharge load. If you have some experience with your cells and your lights, you may be able to get an idea of how much is left in the cell by just reviewing the voltage under load show by the charger during discharge.

Tom


----------



## ferdz

Thanks very much Tom & czAtlantis! 

I initially did a standard discharge on my old AA batteries (labels already peeled off, most likely a 2x Sony 2500mAh or 2700mAh and 2x EcoMax 2100mAh (an Eneloop clone)), but was not able to record the results. If I remember correctly, the results were around 1000-1200mAh so I was a bit surprised if I did it correctly as I thought that capacity should be on the low side as it's supposed to discharge it. So, I put them back again for another discharge and in about 1-2 minutes it was already done and the readings were 12, 10, 2, 10 respectively.

They are now almost done with with their break-in and I'm logging the results for tracking/reference. 

I'm just noticing that Slot #1 of my charger is about 100mAh lower than its pair in Slot #2, while Slots #3 and #4 is just +/-15 with each other. Will still be doing another set of Break-in for 2 pairs of Eneloops after this one.


----------



## march.brown

I have not yet received my C9000 charger, but I have a query that needs to be addressed before I start using it.

Assume that all my cells are at slightly different states of charge , with some fairly fully charged and others in a lower state of charge ... I want to know their proper mAh capacity.

Do I first of all discharge all the cells to 0.9 volts , then charge and discharge them to find the capacity , then charge them again.

OR

Do I charge them fully first , hoping that the charger will take into account the fact that all the cells are in different states of charge , then discharge and re-charge them to find the proper mAh capacity.

At the moment I stick my used or partly used cells on the charger and can see by the number of LCD segments , the state of charge of individual cells ... I now want to put my AA and AAA batteries into batches where the capacities are fairly evenly matched ... I will be using six AA's in Fameart C-cell adaptors in my Wifes "Pure" radio ... The radio takes 190mA whilst playing at a reasonable volume , so in theory my Eneloops should last ten hours ... If all the cells are nearly identical in capacity , they should all start to die at about the same time and the Radio would stop working ... No harm should come to individual cells as they would all (hopefully) be at the same (low) voltage ... If one (only) cell died in the radio first and all the others were still good , then that cell would be reverse charged and might be seriously damaged to the extent that it's capacity would be seriously reduced ... Hence the idea that closely matching cells should be used.

I'm sure that I will eventually get the hang of the new charger , but it doesn't look as though it is a matter of sticking the cells in and powering up the charger (like I do at the moment).
.


----------



## czAtlantis

Charging bays are independent - it means you can put 80% charged cell in bay 1, 10%charged cell in bay2 and even run different programs on every cell (charge, discharge, break-in..)
So if you put your mismatched batteries in charger and run refresh and analyze, some cells (charged ones) will just finish sooner because first phase (charging) will be completed quickly.

But if you want to use Break-in mode you have to discharge all cells first.


----------



## march.brown

czAtlantis said:


> Charging bays are independent - it means you can put 80% charged cell in bay 1, 10%charged cell in bay2 and even run different programs on every cell (charge, discharge, break-in..)
> So if you put your mismatched batteries in charger and run refresh and analyze, some cells (charged ones) will just finish sooner because first phase (charging) will be completed quickly.
> 
> But if you want to use Break-in mode you have to discharge all cells first.


Thank you for the information czAtlantis.

Thank you AlphaZen for the manual in English ... I have printed it off and will try to memorise it all before the charger arrives from Germany.

I will have to scan through this thread again to see if I have missed anything.

It looks as though it is going to take a long time to check all my AA's and AAA's and get them sorted into "similar capacity" groups ... I will have to number each cell with indelible ink to keep track of everything ... 

Previously I just took the required number of batteries out of my stock as required without knowing their exact capacity ... I don't suppose that it mattered too much with single or double cell applications , but with my four and six cell radios it looks as though it is necessary to avoid reverse charging damage to weaker cells.

Still , it gives me something to do when "her indoors" is watching her soaps !

Again , thanks for everyones input.
.


----------



## edpmis02

Any issues with using the charger off a UPS (running off battery power) or car 12v->120v adapter with a stepped sine wave?


----------



## march.brown

Another few possibly silly questions !

In the specifications for the C9000 , it says "Topoff Charging current 100mA" ... Does this mean that when the "DONE" sign appears , the charge drops to 100mA for a period of time ? ... If so how long ? ... When "DONE" appears , there is no charging current displayed , only time , volts and mAh ... How can I see any charging/topoff current.

Also , in the specifications it says "Maintenance Charging Current 10mA" ... Does this mean that after the Topoff finishes , the charger drops down to 10mA for as long as the batteries are on charge ? ... How do we know that the current is down to 10mA ?

If a cell has previously been fully (?) charged in another charger , will the cell suffer from having one amp pushed in by the C9000 ?

Trouble is that in my other three chargers , I just bung the cells in and leave them till the LED says that they are ready ... I do check the temperature of the batteries now and again (by hand) , just in case.

If the C9000 tells me that the cells are charged and I then remove and immediately replace them , Will I then be able to see the mAh charge that has been put in this second time ? ... If I repeat this a few times till no more charge (mAh approaches zero) is displayed , will the cells be totally fully charged ? ... This would be quicker than leaving them in the charger to "Topoff" ... How harmful would it be to my Eneloops.

Do you leave the cells on charge till they reach a particular voltage ? ... Three of mine are showing 1.47V and one (slot two) is showing 1.46V.

I'm sure I will eventually get to trust the C9000 , but I just like to know all the facts !

p.s. All slots are now reading 1.47V.
.


----------



## Yamabushi

march.brown said:


> In the specifications for the C9000 , it says "Topoff Charging current 100mA" ... Does this mean that when the "DONE" sign appears , the charge drops to 100mA for a period of time ? ... If so how long ? ... When "DONE" appears , there is no charging current displayed , only time , volts and mAh ... How can I see any charging/topoff current.


 
Topoff runs 2 hours. You get no information regarding progress or current (an irritating flaw in the UI).



> Also , in the specifications it says "Maintenance Charging Current 10mA" ... Does this mean that after the Topoff finishes , the charger drops down to 10mA for as long as the batteries are on charge ? ... How do we know that the current is down to 10mA ?


 
Yes. Again, no information is displayed.



> If a cell has previously been fully (?) charged in another charger , will the cell suffer from having one amp pushed in by the C9000 ?


 
No. If it's fully charged, it should terminate almost immediately. The exception is the break-in mode which charges for 16 hours; I always discharge fully before starting break-in.



> If the C9000 tells me that the cells are charged and I then remove and immediately replace them , Will I then be able to see the mAh charge that has been put in this second time ? ... If I repeat this a few times till no more charge (mAh approaches zero) is displayed , will the cells be totally fully charged ? ... This would be quicker than leaving them in the charger to "Topoff" ... How harmful would it be to my Eneloops.


 
You'll see the information but I think it will terminate almost immediately each time and you won't get the same capcity result as Topoff.



> Do you leave the cells on charge till they reach a particular voltage ? ... Three of mine are showing 1.47V and one (slot two) is showing 1.46V.


 
I let the charger terminate and topoff by itself.


----------



## SilverFox

Hello March.brown,

The charge termination method for the C9000 is -dv, peak voltage, or time. Many times the charge will terminate on peak voltage. Peak voltage termination is 1.47 volts.

Depending on the age and condition of your cells, this brings the cell to something like 99.5% full charge. The top off charge runs for 2 hours and adds the last 0.5% of the charge.

The top off current is not displayed, nor is the maintenance current. You can see how things are going by checking the voltage of the cell. The voltage at the end of the charge will be 1.47 volts. When the charge ends the voltage will drop slightly, then rise over the next 2 hours during the top off charge. Then it will drop back down. 

The maintenance charge is designed for low self discharge cells in mind and is very low to prevent overcharging damage. Still, the best practice is to remove the cells from the charger when the charge is complete.

When you take a cell off of a charger its voltage will drop. That means that if you put a charged cell into the C9000 it will charge it until the charge termination is triggered. If the cell is already full, very little time will be needed to charge the cell, but some time will be needed. If you did this something like 1000 times, it is possible that you could produce overcharge damage to an Eneloop cell. The system is pretty good, but it is not perfect. It is still recommended to attend to the charge and stop it if you determine anything strange going on.

One of the fun things to do is to check the performance of your other chargers. Charge some cells in your other chargers, let them sit for about 30 minutes, then put them into the C9000 and do a discharge. Come to think of it you can check to see how beneficial the top off charge is. Charge your cells until you see Done, then pull them from the charger, wait 30 minutes, then do a discharge to determine capacity. Next do the same thing but this time allow the cells to stay in the charger for the 2 hour top off charge. Compare your results to determine how much the top off charge benefits the capacity of the cell.

Have fun. 

By the way you can train your wife to use the charger. Tell her to put the cells in the charger and when it says Done to remove and use them. While there are many more features available, charging can be very simple.

Tom


----------



## march.brown

SilverFox said:


> Hello March.brown,
> 
> By the way you can train your wife to use the charger. Tell her to put the cells in the charger and when it says Done to remove and use them. While there are many more features available, charging can be very simple.
> 
> Tom


Thanks for all the info Tom.

w.r.t. My Wife doing her own charging , I don't think I would lke that ... That would open the door for her to show me how the cooker , the washing machine and the dishwasher worked.

"Horses for courses" as the saying goes ... A man has to justify his hobbies by making chargers etc sound very complicated to use ... She did have a look at the display on the C9000 then shrugged and walked away ... I did try to explain how it worked and showed her the diagrams in the instructions , but she just went into the kitchen.
.


----------



## march.brown

Yamabushi said:


> Topoff runs 2 hours. You get no information regarding progress or current (an irritating flaw in the UI).
> 
> I let the charger terminate and topoff by itself.


Hi Yamabushi

I have had a play for a few hours with the C9000 and the voltage does carry on increasing when the "DONE" is displayed ... The voltage creeps up slowly to 1.48V over a period of about two hours which is obviously the "Topoff" period ... Then during what I asume is "Maintenance charging" , the voltage slowly drops to 1.45V ... This is the point at which I removed the cells from the charger.

If I remove a cell which displays "DONE" then put it back in again , the cell is charged again at one amp (or thereabouts) for about one minute (matbe less) then "DONE" comes up again ... The display shows that a few more mAh has been put into the battery and a time of one minute is displayed ... I suppose if this was done a few times it would top up the cell a bit more quickly ... Certainly the charger stops the one amp charge in less than a minute ... I am very happy with the charger now ... Should have bought one earlier , though they were a lot more expensive until recently.
.


----------



## Wrend

It is most likely better for the cells to top them off slowly in this manor, and helps to keep them cool. I also prefer to top off my cells to help insure that they're more balanced at a fully charged state.


----------



## Yamabushi

@ march.brown

Yes, the voltage will give you some indication of progress. I just wish that after "Charging", the display would show "Topoff" and the elapsed time for that step; then show "Done" when it's really finished and goes to maintenance charging rate. 

I agree with Wrend. I think the reduced charge rate, lower temperatures and extended time are all factors in achieving maximum charge. 

Rather than try to tell when each cell is topped off, I simply note the time that the last cell is "Done", wait at least 2 hours, then pull all the cells.


----------



## march.brown

Yamabushi said:


> @ march.brown
> 
> Yes, the voltage will give you some indication of progress. I just wish that after "Charging", the display would show "Topoff" and the elapsed time for that step; then show "Done" when it's really finished and goes to maintenance charging rate.
> 
> I agree with Wrend. I think the reduced charge rate, lower temperatures and extended time are all factors in achieving maximum charge.
> 
> Rather than try to tell when each cell is topped off, I simply note the time that the last cell is "Done", wait at least 2 hours, then pull all the cells.


I found that "DONE" always comes on at 1.46V then after about two hours the voltage gradually goes up to 1.47V or 1.48V though I did have a Hybrio show 1.49V ... After another hour or so , the voltage drops to about 1.45V or 1.46V ... I will now use the Hybrios in equipment that doesn't demand the ultimate in closely matched capacity and will only buy Eneloops from now on.

I also will be waiting for the last cell to say "DONE" and will wait for at least two more hours before taking them out of the charger ... Based on the voltage readings that I noted , I would be happy to leave the batteries on for rather more than the two hours ... After the two hours "Topoff" at 100mA , a 10mA float charge (maintenance) isn't going to damage the NiMh cells ... I wouldn't leave them on all day though , just for my own peace of mind.

In all fairness , you will only lose a small percentage of charge if you remove the batteries when the "DONE" comes on ... It's just that the cell capacity is maximised when the two hours of "Topoff" has elapsed.

Perhaps in the future , the next generation will show that the charging is "done" but the "topoff" is in progress ... Then "Topoff Done" will display ... That would be one step nearer perfection ... Till that happens , I will just add a couple of hours or more onto the "DONE" time.
.


----------



## apagogeas

march.brown said:


> ...
> If I remove a cell which displays "DONE" then put it back in again , the cell is charged again at one amp (or thereabouts) for about one minute (matbe less) then "DONE" comes up again ... The display shows that a few more mAh has been put into the battery and a time of one minute is displayed ... I suppose if this was done a few times it would top up the cell a bit more quickly ... Certainly the charger stops the one amp charge in less than a minute ... I am very happy with the charger now ... Should have bought one earlier , though they were a lot more expensive until recently.



From what I can recall from memory, 1A charge will bring the cell up to around 95% full. The rest will be filled up by the 2 hours top up. NiMH can easily handle high currents during charging up to 80-90% or so (what the 15 minute chargers take advantage of). However, the remaining 10%, if pumped in with the same high current, it stresses the cell and reduces the useful life. So, indeed you may put much quicker the missing 5% capacity instead of waiting for the top up to finish, however this approach invalidates the very first reason served by the top up; to fill up the cell gently so not to stress and ruin it much quicker. I really wouldn't miss a 5% charge if I'm in a hurry and can't wait for a top up to finish, if this means my cells will live longer.
Also, doing so lurks a dangerous situation. Maha is smart enough so not to miss a fully charged cell, although it still needs to put current for 1 minute to figure that out. However, if you had another charger which rely just on -dV, a fully charged cell may not produce that necessary -dV (the cell is past the point of that signal), so it will pump in current till the timer expires. We can't be certain even for maha, it may be fooled in that case. Of course this is rather bad if it happens.


----------



## march.brown

march.brown said:


> Perhaps in the future , the next generation will show that the charging is "done" but the "topoff" is in progress ... Then "Topoff Done" will display ... That would be one step nearer perfection ... Till that happens , I will just add a couple of hours or more onto the "DONE" time.
> .



Just realised that if the C9000 displayed the charging current *after* the "DONE" comes up , that would enable us to see the 100mA and the 10mA periods of charge ... The cells could be removed when the 10mA figure showed ... That must be a very easy mod for Powerex to do.

I am charging my AAA's at 400mA at the moment ... They are all 800mAh cells ... Does the "Topoff" still stay at 100mA when the charging rate is only 400mA ? ... After "DONE" comes up , the C9000 would try to put 200mAh (2 hours at 100mA) into a 95% charged 800mAh cell ... This 200mAh into a 2000mAh cell is an extra 10% , but into a charged 800mAh cell it is 25% ... Would it be better to only give the AAA cells a one hour "Topoff" ? ... I will remove the AAA cells after one hour just in case.

It would be nice if the C9000 had a memory so that at the press of a single button you could tell it to charge all four slots at 400mA ... It's no real hardship for me to alter the charge current manually for AAA's as I only have about twenty ... I will always charge my AA Eneloops at the 1000mA so that suits me fine.

The charger and batteries all seem to stay quite cool during use .. So far I am very impressed with the chargers performance..
.


----------



## apagogeas

Maha charges up to 95% because it usually terminates on voltage. If the termination is on -dV, the cell will be at 100% SoC (this signal occurs after the cell is fully charged). The ideal maha for me would know which method terminated the charge and based on that to decide if a top up is needed. If it is on voltage, a top up can be applied, if it is on -dV, no top up. The charging efficiency beyond a SoC is not 100%, also the lower the charging current, the lower the charging efficiency (around 70% for 0.1C). Therefore, even the 2 hours top up at 100mAh will not put 200mA in the cell. From one point of view, a 2000mAh cell under top up is like being charged at 0.05C and a 800mAh at 0.125C which is about what the break-in do to saturate the cell. True, cells with lower than 1000mAh, this will be tougher anyway but it will not result in a 25% overcharge due to charging inefficiency at that stage. Problems are pronounced with capacities below 700mAh, where the top up is more close to 0.2C which isn't very healthy anyway. I'd love a maha that sets the top up at 0.1 * charging rate (or max 100mA), so in the case of AAA, it would be 40mA for a 400mA charge, much gentler than the current 100mA setting. Anyway, what is more damaging to a cell is to leave it on the charger forever on trickle charge. LSD do not lose even those 10mA/hour.


----------



## march.brown

apagogeas said:


> Maha charges up to 95% because it usually terminates on voltage. If the termination is on -dV, the cell will be at 100% SoC (this signal occurs after the cell is fully charged). The ideal maha for me would know which method terminated the charge and based on that to decide if a top up is needed. If it is on voltage, a top up can be applied, if it is on -dV, no top up. The charging efficiency beyond a SoC is not 100%, also the lower the charging current, the lower the charging efficiency (around 70% for 0.1C). Therefore, even the 2 hours top up at 100mAh will not put 200mA in the cell. From one point of view, a 2000mAh cell under top up is like being charged at 0.05C and a 800mAh at 0.125C which is about what the break-in do to saturate the cell. True, cells with lower than 1000mAh, this will be tougher anyway but it will not result in a 25% overcharge due to charging inefficiency at that stage. Problems are pronounced with capacities below 700mAh, where the top up is more close to 0.2C which isn't very healthy anyway. I'd love a maha that sets the top up at 0.1 * charging rate (or max 100mA), so in the case of AAA, it would be 40mA for a 400mA charge, much gentler than the current 100mA setting. Anyway, what is more damaging to a cell is to leave it on the charger forever on trickle charge. LSD do not lose even those 10mA/hour.


I have just charged 12 AAA cells (in the C9000) that were charged two weeks ago in one of my other chargers ... With my other chargers , I normally remove the charged batteries when the charger indicates that the charge is complete ... Theoretically they should all have been in the same state of charge.

The Eneloops were all displaying "DONE" within two or three minutes and their charge given showed between 21mAh and 25mAh ... So the Eneloops were still virtually fully charged , which is what I expected (or hoped for) ... My Recyko cells were showing between 43mAh and 44mAh before they were "DONE" ... My Hybrios were showing a wider spread between 25mAh and 49mAh ... I won't be buying any more of these Hybrio or Recyko AAA's and will stick with Eneloops till perhaps something better comes along in the future.

After a one hour topoff I removed four of the AAA's and then replaced them and put them back on charge at 400mA ... They all came up as "DONE" after one minute and 1mAh was displayed for each of them ... I will now standardise the AAA charging rate at 400mA and will leave them charging for only one hour after the "DONE" is displayed.

I'm happy now I've had a little play !
.


----------



## PEU

ferdz said:


> I'm not sure if I missed it or anything, but is there a way to determine the capacity of the battery without using R&A? Like plugging it in then pressing some buttons and it will show the status of the battery.



Check ZTS battery testers


Pablo


----------



## fiberguy

Two things that I'd really like on this charger would be:

A switch to activate a tone signaling the charging cycle is complete

A separate timer that begins counting UP for each channel once charging is complete (although noting the time you started your charge would work as well)

Another user on another thread mentioned data storage for individual battery charge info and the ability to interface on a computer, also excellent ideas. I'm just sayin, if they're gonna be the best, why not go all out?


----------



## Schermann

Just don't get it! 

I pull the C9000 out of it's box and plug it in, all ok. 

I pop in a Eneloop AAA into slot one, all ok. 

Then I select 'break-in', set charge/discharge, all ok. 

I hit enter to initiate and it powers OFF! 

Do this 3 times and OFF! Starting to wonder if DOA... 

After this it worked fine without a hitch since! 

What gives, I thought these units were fully 'burnt in' before they left the factory? 

version - 0L0EA


----------



## czAtlantis

Maybe just bad contact(dirt, oxidation..) between battery and charger? Because when Maha tries to charge and cell has extreme internal resistance (or there is no cell :-D ) it powers down thinking there is no battery.


----------



## bbb74

Schermann said:


> Just don't get it!
> 
> I pull the C9000 out of it's box and plug it in, all ok.
> 
> I pop in a Eneloop AAA into slot one, all ok.
> 
> Then I select 'break-in', set charge/discharge, all ok.
> 
> I hit enter to initiate and it powers OFF!
> 
> Do this 3 times and OFF! Starting to wonder if DOA...
> 
> After this it worked fine without a hitch since!
> 
> What gives, I thought these units were fully 'burnt in' before they left the factory?
> 
> version - 0L0EA



If you don't put the AAA's in securely this can happen. You need to give them a good push so they really do "click" into place. Without that click noise, the contact may be poor and the charger will stop seeing the battery there.


----------



## Schermann

Please in the next firmware reissue can you have a user adjustable rejection voltage or 'HIGH'

Give us the option of setting our own values...


----------



## DT 123

AFAIK break-in only defines the charging-discharging-charging process. It doesn't say anything about the condition of the cells before the first charging.
Several user asked here in the last years whether they should discharge the cells first. Answers were always that it doesn't really matter.

I always discharged them first. Also to know how much capacity was left.
By accident (I didn't have enough time for discharging) I did a break-in with almost full cells. I got in that case about 3% (40-60 mAh) better results.
Did anyone else get similar results? I tested altogether 3 sets of 4 cells (Eneloop AA).
The break-in of a discharged cell gives me results of 1960-2000 mAh. 
If I start the break-in some days after charging the cells without doing a discharge in prior then the result were 2020-2060 mAh.

The break-in tests of a 3 year old Noname LSD-Set showed similar results:


Code:


                  #1      #2      #3       #4    
10.01.2012       1890    1872    1828    1880    with discharge
11.08.2012       1886    1874    1827    1880    with discharge
05.09.2012       1928    1916    1883    1915    without discharge


----------



## Planz

After reading several threads, I'm not sure which thread to post so I picked this as there seems to be many knowledgable folks who might be able to help.
I have several equipment (meters, door bell, etc) that use 9V batteries. I read that alkalines leak and I have many bad experiences with AA/AAA alkalines leaking but I don't seem to recall any 9V alkaline leaking. Is it true that 9V alkalines don't leak or am I mistaken?
Also, unlike AAA/AA, 9V lithium primaries are less common, are they?
Finally, I'm considering to buy a Maha 9V charger and use NiMH but I'm not sure if it will work accurately with digital multi meters as the manufacturers (fluke for example) seem not to want to comment on using NiMH battery. They seem to say they test based on alkalines.
Yours thoughts please. Thanks.


----------



## Yamabushi

9V alkaline batteries are less likely to visibly leak because they contain 6 x 1.5 cells, each having their own shell. i.e., the rectangular shell acts as secondary confinement.

9V lithium are not as common as AA or AAA lithium (you may not find them in the corner convenience store) but they aren't hard to find in hardware and electronics stores.

Most 9V NiMH are really 7.2V; that may be an issue for some devices. Powerex makes a Maha Imedion 9.6V battery; they also make (made?) a 8.4V version (it may be discontinued but is still available from some sellers).


----------



## Planz

Thank you Yamabushi.
It's good to know that at least there's a secondary confinement with the rectangular shell.





Yamabushi said:


> 9V alkaline batteries are less likely to visibly leak because they contain 6 x 1.5 cells, each having their own shell. i.e., the rectangular shell acts as secondary confinement.
> 
> 9V lithium are not as common as AA or AAA lithium (you may not find them in the corner convenience store) but they aren't hard to find in hardware and electronics stores.
> 
> Most 9V NiMH are really 7.2V; that may be an issue for some devices. Powerex makes a Maha Imedion 9.6V battery; they also make (made?) a 8.4V version (it may be discontinued but is still available from some sellers).


----------



## donn_

After reading about it for years, I finally bit the bullet and bought a 9000. It arrived yesterday, along with a dozen new Eneloop XX cells and a nice yellow Powerpax Storacell.

I started with a discharge on the first 4 cells, and am deep into a Break-In at the moment.

So far, my favorite feature is the 9000 plugs into the same 12V2A power cable as my Xtar SP2 charger.


----------



## Schermann

Had my C9000 for a while now. Besides a setting index glitch alls fine. 

One issue is the unit reboots continuously when started below 10C room temp! It will reboot until something warms up and then it's a GO!

HIGH batteries should be pulse TESTED by the C9000 for 2 mins to warm them up a bit, since most are not HIGH once they are warmed!!!

For HIGH batteries, I just discharge them and recharge using a dumb Sanyo NiMH 200 mA wall charger since the C9000 fails at this!

Just bought some Eneloop AA 2500 mAh, the refresh only got them to 2380 mAh! Is this normal and will they improve capacity by use?


----------



## Grayson73

Schermann said:


> Had my C9000 for a while now. Besides a setting index glitch alls fine.
> 
> One issue is the unit reboots continuously when started below 10C room temp! It will reboot until something warms up and then it's a GO!
> 
> HIGH batteries should be pulse TESTED by the C9000 for 2 mins to warm them up a bit, since most are not HIGH once they are warmed!!!
> 
> For HIGH batteries, I just discharge them and recharge using a dumb Sanyo NiMH 200 mA wall charger since the C9000 fails at this!
> 
> Just bought some Eneloop AA 2500 mAh, the refresh only got them to 2380 mAh! Is this normal and will they improve capacity by use?



I usually throw out the HIGH batteries because they tend to be the older ones that don't hold much of a charge.


----------



## Russel

Schermann said:


> [...]Just bought some Eneloop AA 2500 mAh, the refresh only got them to 2380 mAh! Is this normal and will they improve capacity by use?



If you want to compare apples to apples, run the cells through a break-in. The break-in mode measures the capacity following the IEC standard that is used to rate the capacity. Refresh mode is a little different. The numbers you get when running refresh are good for relative measurements. 

I wouldn't be concerned with the numbers you got when running a refresh. Like I said, if you want something to compare to the capacity rating of the cell, run a break-in mode.


----------



## Yamabushi

Schermann said:


> Just bought some Eneloop AA 2500 mAh, the refresh only got them to 2380 mAh! Is this normal and will they improve capacity by use?



Depending on the charge/discharge rates you used, that seems low. I ran Refresh on 24 new Sanyo XX HR-3UWX (i.e., 1st generation XX) at 1000 mA charge / 1000 mA discharge. Lowest was 2413 mAh; highest was 2498 mAh.


----------



## Mr Happy

Schermann said:


> Just bought some Eneloop AA 2500 mAh, the refresh only got them to 2380 mAh! Is this normal and will they improve capacity by use?



If they are brand new their capacity will improve after a few charge/discharge cycles. If you have time you might also run them through a break-in cycle.


----------



## donn_

I just finished a break-in on a set of 4 new XX cells, and got 2405-2430.


----------



## Technojunky

Hi, I have just bought a MH-C9000 and I'm currently running a "Break- In" cycle on a new set of Eneloop AAA batteries as an 800 Mah charge rate.. The break-in has been running for about 30 hours but the display is currently showing some weird results.

Slot 1 shows "charge" 23MAH 78MA 1.28V 19min
Slot 2 "done" 3MAH 1.5V 
Slot 3 "charge" 17MAH 79MA 40 1.27V 40min
Slot 4 "charge" 16MAH 79MA 13min 1.27V 

I set the charge rate at 800Mah so why is slot 2 showing as "done" and only reading 3 Mah ? Additionally, surely the other batteries should be charging at a higher rate !

I'm very new to this so any helpful advice would be much appreciated.

Thank you.


----------



## Kick

I would say the cell in slot # 2 may be bad. The cell in slot # 3 may be suspect as well. The other two cells look normal, just let the charger finish. You still have 15 hours to go. Once the others are finished you will have a more accurate assessment of how the cells will perform.


----------



## Mr Happy

mAh is not a charge rate, it is a charge (80 mA x 10 hours = 800 mAh). mA is a charge rate (rate = amount of charge per unit time), and hours, minutes, seconds are time.

When you set up the break-in cycle on the C9000 you enter the battery capacity in mAh (e.g. 800 mAh for AAA cells). The C9000 then divides this number by 10 and sets that as the charge rate (800 mAh / 10 h = 80 mA).

It looks like slot 2 had a problem. Sometimes this may be because the wrapper at the negative end of the battery gets in the way of the contact spring. You might try re-seating the battery in the charger and trying again.

The other slots look like they are on the second charge cycle after the discharge. I think you need to leave them for another 15 hours or so to finish. A complete break-in cycle takes nearly two days.


----------



## Technojunky

Thanks for the post Kick, I'll see what number 2 is like after the break in.

Thank you for taking the time to write the detailed explanation Mr Happy, I've certainly now got more idea about what the display s actually telling me. I'll post back the final results once the "break in" has finished.


----------



## Kick

Technojunky said:


> Thanks for the post Kick, I'll see what number 2 is like after the break in.
> 
> Thank you for taking the time to write the detailed explanation Mr Happy, I've certainly now got more idea about what the display s actually telling me. I'll post back the final results once the "break in" has finished.


You don't have to wait until the others are done, because each slot is independent of the others. Pull cell #2 out , re-seat it, discharge it, then run the break-in again. As Mr. Happy explained it may not be in the charger properly. Just be ready to wait the 40 or so hours it will take.:sigh:

Yes, thank you Mr. Happy. Your detailed explanation was very informative on how to read the display of the charger. I am addicted to this site so that I can completely geek out. Props to all the informative posts to assist others here.


----------



## lowks

Is there anyway to change the charging current for Maha after the battery has been charging for sometime ala La Crosse ?


----------



## Kick

I don't know for sure, I have only had my charger for a week. If it were me, I'd pull the cell out, discharge, then charge at the desired rate.


----------



## donn_

I'm running break-in on 4 old Eneloop 2000mAh cells, and expected unusual readings on them. They are 3-4 years old, and have always been slow charged, and frequently refreshed on a MH-C808M.

I discharged the cells before starting the BI, but didn't pay attention to the readings during the discharge or after the first charge-up.

One cell stopped discharge over an hour before the others, and read 1345mAh. It rested for an hour and started charging.

Another cell stopped discharge at 1775mAh and is still resting.

The other 2 are still discharging, at 1850+mAh and are over 300 minutes in.

What should I assume about and do about the two cells which apparently have much less capacity?

Edited to add: the final 2 cells went into rest at 1870mAh.


----------



## SilverFox

Hello Donn,

You may want to take the two lowest cells and simply charge them at 1000 mA followed by a discharge at 500 mA. Compare the results. If they show the same reduced capacity you may want to find other uses for them. I recycle cells that fall below 80% of their initial capacity.

Tom


----------



## donn_

I'll do that , Tom. I'm running all my older cells (it turns out they are older than I thought...2006), and will collect the lower cap cells for an attempt at refreshing them. Should I discharge first?


----------



## Mr Happy

You can always discharge a cell after the break-in cycle completes to see if there is any improvement in the reported capacity. Recall that the break-in cycle does a charge, then a discharge-and-measure, then a second charge. The second charge may give an improvement in cell condition beyond the first charge, so if the reported capacity is lower than you expect it is worth discharging the cell again to see if it got any better after the second charge.

One reason for the reported capacity on discharge to be low is a high internal resistance in the cell causing an early end to the discharge due to voltage sag. It may take more than one break-in cycle to fix this in some cases. However, if the cell is genuinely worn out than no amount of break-in cycles will produce an improvement.


----------



## Ollifi

Is there some replacement thread for this,since no one seems to be chatting here recently?


----------



## AlphaZen

Ollifi said:


> Is there some replacement thread for this,since no one seems to be chatting here recently?


No, this is it. Not much chat because most everything has already been covered.


----------



## SilverFox

Hello Ollifi,

Welcome to CPF.

Most of the "issues" with this charger have been worked out and are covered in this thread and the first thread that this is a continuation of.

If you have a specific question feel free to ask it here.

Tom


----------



## donn_

SilverFox said:


> Hello Donn,
> 
> You may want to take the two lowest cells and simply charge them at 1000 mA followed by a discharge at 500 mA. Compare the results. If they show the same reduced capacity you may want to find other uses for them. I recycle cells that fall below 80% of their initial capacity.
> 
> Tom



I should have known not to count on my aging memory. Instead of your suggestion, I did a 500mA discharge followed by a break-in cycle. The break-in discharge just completed, so here are the results of 4 discharges; 2 initial discharges and 2 break-in discharges. On the first 2 cells, I did not record the results of the first initial (?) discharge:

????/1348/1691/1892

????/1772/1654/1798

1254/1645/1538/1641

1373/1747/1662/1745

These 4 cells were the only cells out of 24 to initially read lower than 1800mAh.

Interesting that the last 3 cells dropped in capacity between the first break-in discharge and the second initial discharge. I wonder if it's because they sat idle for a few days after the first break-in.

After their second break-in is finished, tomorrow morning, I intend to keep working on the three which are still under 1800. I'll start with a preliminary discharge, but should I follow it with a BI or an R&A?

I have to say I'm pretty impressed with the performance of the cells overall. They're all from 2006, and have been in pretty much constant use. They've been cycled a minimum of 72 times, and some 2-3 times that many. The fact twenty of them are still able to provide over 80% of their rated capacity seems to be admirable.

I also must say how happy I am with the C9000. It's been running non-stop since Feb 27 without even the slightest hiccup. I bought a cheap little tablet computer stand for it, and it stands beside my monitor, adjusted to make the display readable, and just keeps ticking along.


----------



## SilverFox

Hello Donn,

Just do a normal charge and discharge. It is much quicker than a Break In. All you are looking for is to see if the cell capacity is coming back or if it is shot. Sometimes exercising a cell with a few charge/discharge cycles will rejuvenate them a little. Once you "whip" them back into shape you can do a Break In to record their capacity for future reference.

Tom


----------



## donn_

Hi Tom,

I gave them 3 charge/discharge cycles and the capacity kept dropping, so I retired them. They didn't owe me anything.


----------



## mayo

I've had my C9000 for about two weeks and I'm having a blast. I've been reading the posts for the last two weeks but have a question...Could someone explain in detail how the discharge mode works. What stops the discharge and is the voltage reading when done an average? Thanks


----------



## apagogeas

mayo said:


> I've had my C9000 for about two weeks and I'm having a blast. I've been reading the posts for the last two weeks but have a question...Could someone explain in detail how the discharge mode works. What stops the discharge and is the voltage reading when done acycle.n average? Thanks



Maha discharges at bursts of 1A. This is the load during discharge and when then voltage under load reaches 0.9V (0.89 really but you'll not see that) it terminates. Since the discharge is performed at 1A, the only reason you get a higher mAh reading when using a low mA discharge setting is the recovery of the battery during the paused cycle. So at 100mA discharge, discharge occurs 10% of the cycle time and 90% is paused and whilst paused the battery recovers a bit before the next discharge cycle.


----------



## Mr Happy

mayo said:


> I've had my C9000 for about two weeks and I'm having a blast. I've been reading the posts for the last two weeks but have a question...Could someone explain in detail how the discharge mode works. What stops the discharge and is the voltage reading when done an average? Thanks



Further to apagogeas the typical voltage reading after the discharge stops should recover to about 1.2 V. You can tell something about the health and vibrancy of the cell from this voltage. If it is, say, 1.2 V the cell is likely strong and able to maintain a good voltage under load. However, if the post discharge voltage is higher, like 1.25 V, it means the cell is weaker and less suitable for heavy loads.


----------



## mayo

Mr Happy said:


> Further to apagogeas the typical voltage reading after the discharge stops should recover to about 1.2 V. You can tell something about the health and vibrancy of the cell from this voltage. If it is, say, 1.2 V the cell is likely strong and able to maintain a good voltage under load. However, if the post discharge voltage is higher, like 1.25 V, it means the cell is weaker and less suitable for heavy loads.



Thanks for quick response guys. Does the voltage change while done is displayed for say 30 minutes? or do I need to take it out and measure it?


----------



## RCM

It changes as the cell voltage changes, my worst ones come back up to 1.3 or so volts! They also show HIGH...I've been learning a lot about NiMH by how these behave!


----------



## gosmond

Hello - I've read at least 50 pages of posts, threads, and Amazon reviews on the MH-C9000 (and the LaCrosse units.)

I am still unclear on a few things about the MH-C9000:

1) Does it make a clicking noise when it charges?
2) What happens if you just drop AAA's in and let them charge "hands free," in the default 1000ma charge mode? Do they overheat? Any safety issue? 
3) If no overheat / safety problem with AAA's in "hands free" mode, what is the estimated shortening of useful life caused by the extremely high charge rate?
4) Anyone hear of any useful firmware or product updates that may be coming down the line, such as the ability to set mode & charge rate for all 4 cells at once, to change the default charge rate from 1000ma to a lower rate, or a switch to dim or cut off the backlight?

Thank you for your detailed reply.

-Gosmond


----------



## Russel

gosmond said:


> [...]
> 1) Does it make a clicking noise when it charges?
> [...]



If it does, I can't hear it. But, my hearing isn't the best. Some people may be able to hear it.

The probable reason for clicking... The MH-C9000 pulses a 2 amp current to charge the cells, varying the pulse width to adjust the average current. It also pulses a 1 amp discharge current when discharging and also adjusts the duty cycle to set the average discharge current.

http://www.candlepowerforums.com/vb...age-measured&p=3581455&viewfull=1#post3581455


----------



## Mr Happy

gosmond said:


> Hello - I've read at least 50 pages of posts, threads, and Amazon reviews on the MH-C9000 (and the LaCrosse units.)
> 
> I am still unclear on a few things about the MH-C9000:
> 
> 1) Does it make a clicking noise when it charges?
> 2) What happens if you just drop AAA's in and let them charge "hands free," in the default 1000ma charge mode? Do they overheat? Any safety issue?
> 3) If no overheat / safety problem with AAA's in "hands free" mode, what is the estimated shortening of useful life caused by the extremely high charge rate?
> 4) Anyone hear of any useful firmware or product updates that may be coming down the line, such as the ability to set mode & charge rate for all 4 cells at once, to change the default charge rate from 1000ma to a lower rate, or a switch to dim or cut off the backlight?
> 
> Thank you for your detailed reply.
> 
> -Gosmond



1) Older units make a slightly audible high pitched tone when charging, but newer units have been reported to be silent.
2) Brand new cells would probably survive this treatment, but older cells may be harmed. Best not to do this.
3) See (2).
4) The C9000 is not considered firmware modifiable or upgradable. It comes as it comes and does what it does. However, many comments about the user interface being complicated are overstated. Using the charger is really simple and can almost be done blindfolded.


----------



## gosmond

Thanks for your replies. I ordered an MH-C9000 today and will share my comments & experiences with it after I've had a week or so to test it out.

-Gosmond


----------



## N8N

How does the C9000 detect that a battery is inserted? Mechanically, or by detecting voltage?

Reason I ask is I have some old NiMH C-cells (probably bought from DX - yeah, I know) that I've used in one of the Task Force flashlights, they work fairly well actually. Would like to start using the C9000 to charge them but they won't physically fit. However I don't see why a C-cell battery holder, some wire, and maybe some "dummy cells" made from wooden dowel etc. wouldn't allow the C9000 to charge them. Thoughts?

I may just run to the store and get some appropriately sized dowel and experiment...


----------



## Power Me Up

N8N said:


> How does the C9000 detect that a battery is inserted? Mechanically, or by detecting voltage?



It will be by voltage.



> Reason I ask is I have some old NiMH C-cells (probably bought from DX - yeah, I know) that I've used in one of the Task Force flashlights, they work fairly well actually. Would like to start using the C9000 to charge them but they won't physically fit. However I don't see why a C-cell battery holder, some wire, and maybe some "dummy cells" made from wooden dowel etc. wouldn't allow the C9000 to charge them. Thoughts?
> 
> I may just run to the store and get some appropriately sized dowel and experiment...



Yes, it can certainly be done - I've done it myself. I'll give you a link to some pictures of what someone else has done - their setup looks a lot better than mine:

http://www.candlepowerforums.com/vb...n-Maha-C9000&p=3287103&viewfull=1#post3287103


----------



## N8N

awesome. To the hardware store!


----------



## Russel

I prefer the updated version:
http://www.candlepowerforums.com/vb...n-Maha-C9000&p=3375588&viewfull=1#post3375588

The MH-C9000 detects the presence of a battery by the voltage, then when set to charge, performs an impedance test. If the internal resistance determined by the impedance test is too high, the battery is rejected and the display shows "high" signifying excessively high internal resistance. If you install one battery and set it to charge, then watch closely for the first voltage reading, it will give you what usually appears to be a overly high voltage. You have too watch closely because the voltage reverts back to the actual battery voltage after the first reading. That first reading is the results from the impedance test. 1.5 volts or so is good, 2 or more volts (if I remember correctly) is rejected and "high" is displayed. 

Also, (again, if I remember correctly) the maximum charge capacity for the MH-C9000 (current versions) is about 4000 mAh. With the exception of break in mode. The adapters that I made for connecting D cells to a C9000 were for discharge testing and to perform break in. I normally charge D cell NiMH cells in a MH-C808M charger.


----------



## picrthis

You can buy ready made adapters for C & D cells that fit the C9000.

http://www.ebay.com/itm/2-Pack-Batt...07480?pt=Battery_Chargers&hash=item4d0ca1bab8


----------



## Power Me Up

Nice!

It's a pity that the postage to send them to Australia is more than they cost!

Group buy maybe?


----------



## tatasal

PICRTHIS: thanks for the info on the C9000 adaptor-- ordered a pair


----------



## N8N

Nice find and thanks for the heads up. Anyone tried them yet?


----------



## Rexlion

Cool! I had to have a pair of those adapters for my D cells.


----------



## picrthis

tatasal said:


> PICRTHIS: thanks for the info on the C9000 adaptor-- ordered a pair


Your very welcome, I never seen anybdoy mention these before.



N8N said:


> Nice find and thanks for the heads up. Anyone tried them yet?


Did you see my picture on my actual charger?



Rexlion said:


> Cool! I had to have a pair of those adapters for my D cells.


I don't blame you, they are very nicely made and fit perfectly.


----------



## tatasal

Are these adaptors aftermarket items or are they made by Maha?


----------



## picrthis

Aftermarket.


----------



## tatasal

picrthis said:


> Aftermarket.



I hope it's made nicely enough as to have a very positive contact piggybacking on the C9000? Does it?


----------



## picrthis

No worries, when I said aftermarket I just meant they are not made by powerex, however they are made by the company that makes the BM200 and in-fact they come with that charger/analyzer as standard accessories and are also sold separately; they fit the C9000 perfectly and are advertised by the seller as such too.

http://www.ebay.com/itm/BM200-Batte...473?pt=US_Battery_Testers&hash=item4d0c4d16b9


----------



## tatasal

Using the C9000, do you charge your high-capacity D cell (8500mah+) 2.5X for it to be 'filled it to the brim', so to speak?


----------



## N8N

I saw the pic but wasn't sure if that was yours or a stock photo. I'm assuming then since you actually have them that they work well, off to the bay!


----------



## picrthis

tatasal said:


> Using the C9000, do you charge your high-capacity D cell (8500mah+) 2.5X for it to be 'filled it to the brim', so to speak?


I only have used it to test some D cells with it.



N8N said:


> I saw the pic but wasn't sure if that was yours or a stock photo. I'm assuming then since you actually have them that they work well, off to the bay!


That's an actual picture of my personal charger and adapters that I put on the couch and took a quick picture of so I could post it here, I thought that was obvious; my bad I guess it wasn't.


----------



## picrthis

Power Me Up said:


> Nice!
> 
> It's a pity that the postage to send them to Australia is more than they cost!
> 
> Group buy maybe?


Yea I just checked it out of curiosity and it would be around $13 International 1st Class with no tracking though; that's the cheapest they have.


----------



## Russel

tatasal said:


> Using the C9000, do you charge your high-capacity D cell (8500mah+) 2.5X for it to be 'filled it to the brim', so to speak?



Yes. Technically, it would be three times, assuming the batteries are fully discharged. Break in mode doesn't have that limitation, but isn't the best way to charge the cells on a daily basis.


----------



## TakeTheActive

*SOMETHING COMPLETELY NEW For the Maha MH-C9000: Custom C/D Adapters!*





picrthis said:


> You can buy ready made adapters for C & D cells that fit the C9000.
> 
> http://www.ebay.com/itm/2-Pack-Batt...07480?pt=Battery_Chargers&hash=item4d0ca1bab8


.



picrthis said:


> No worries, when I said aftermarket I just meant *they are not made by powerex, however they are made by the company that makes the BM200* and in-fact they come with that charger/analyzer as standard accessories *and are also sold separately*; they fit the C9000 perfectly and are advertised by the seller as such too.
> 
> http://www.ebay.com/itm/BM200-Batte...473?pt=US_Battery_Testers&hash=item4d0c4d16b9


.



tatasal said:


> *Using the C9000, do you charge your high-capacity D cell (8500mah+) 2.5X* for it to be 'filled it to the brim', so to speak?


.



Russel said:


> Yes. *Technically, it would be three times*, assuming the batteries are fully discharged. Break in mode doesn't have that limitation, but isn't the best way to charge the cells on a daily basis.



Wow *Russel*!!!

I always thought that YOUR setup: *Re: Testing C/D cells in Maha C9000*
.


.
was the "_Cats Meow_" for C / D cells. Unable to duplicate it, I bought 16 magnets from the web site you recommended (sorry folks, I can't remember the name  ) and soldered up 4 ~6" wires with eyelets to Test / Charge my C / D cells on my C9000.

*BUT*, even @ $13 US for 2, these C / D Adapters look neat!  (Considering the MAN-HOURS it took to build your setup!!!  :wow: )

Something NEW, after SOOOO LOOONG, to add to my FAQ.  

Thanks *picrthis* for finding this! *______________________________*​.
Now, regarding a "*high-capacity D cell (8500mah+)*", I'm confused with the 2.5X vs 3.0X discussion regarding the C9000. AFAIK, the optimum Charge Rate would be 0.5C (4250mA) and we want to Charge to ~120% Capacity (~10,200mAh). Whether we Charge @ the MAX of 2000mA, or Break-In @ the MAX of 20A x 0.1 (2.0A / 2000mA), how do we achieve 4250mA /0.5C, or Charge @ over 2000mA?  

[Maybe I've been away from the forum too long and have forgotten something?!? ]

*UPDATE: *Looking again at the eBay photos, this new *BM200* looks so much like the offspring of a C9000 and a BC-900/9009/1000. :huh:


----------



## Russel

*Re: SOMETHING COMPLETELY NEW For the Maha MH-C9000: Custom C/D Adapters!*



TakeTheActive said:


> [...]Now, regarding a "*high-capacity D cell (8500mah+)*", I'm confused with the 2.5X vs 3.0X discussion regarding the C9000. AFAIK, the optimum Charge Rate would be 0.5C (4250mA) and we want to Charge to ~120% Capacity (~10,200mAh). Whether we Charge @ the MAX of 2000mA, or Break-In @ the MAX of 20A x 0.1 (2.0A / 2000mA), how do we achieve 4250mA /0.5C, or Charge @ over 2000mA?
> 
> [Maybe I've been away from the forum too long and have forgotten something?!? ][...]





Haven't seen you post in a while TakeTheActive! It's good to see you active!

The 2.5 and 3X is referring to the number of regular charge cycles needed to fully charge a completely depleted D cell. During the normal charge cycle, the MH-C9000 has a charge capacity limit of something like 4000 mAh. So, the charger would have to be restarted a couple or three times to completely charge an 8000 mAh to 10000 mAh D cell. Of course, that is not the case when using the break in mode. I only use the MH-C9000 for testing and running D cell through a break in cycle. I use a MH-C808M to charge them. The MH-C808M charges at a pulsed 2000 mA charge current, and the Accuevolution D cell that I have recommend charging at 2000 mA. So far my old D cells have been working very well.


----------



## picrthis

*Re: SOMETHING COMPLETELY NEW For the Maha MH-C9000: Custom C/D Adapters!*



TakeTheActive said:


> .
> was the "_Cats Meow_" for C / D cells. Unable to duplicate it, I bought 16 magnets from the web site you recommended (sorry folks, I can't remember the name  ) and soldered up 4 ~6" wires with eyelets to Test / Charge my C / D cells on my C9000.
> 
> *BUT*, even @ $13 US for 2, these C / D Adapters look neat!  (Considering the MAN-HOURS it took to build your setup!!!  :wow: )
> 
> Something NEW, after SOOOO LOOONG, to add to my FAQ.
> 
> Thanks *picrthis* for finding this! *______________________________*​.
> Now, regarding a "*high-capacity D cell (8500mah+)*", I'm confused with the 2.5X vs 3.0X discussion regarding the C9000. AFAIK, the optimum Charge Rate would be 0.5C (4250mA) and we want to Charge to ~120% Capacity (~10,200mAh). Whether we Charge @ the MAX of 2000mA, or Break-In @ the MAX of 20A x 0.1 (2.0A / 2000mA), how do we achieve 4250mA /0.5C, or Charge @ over 2000mA?
> 
> [Maybe I've been away from the forum too long and have forgotten something?!? ]
> 
> *UPDATE: *Looking again at the eBay photos, this new *BM200* looks so much like the offspring of a C9000 and a BC-900/9009/1000. :huh:



Yes the BM200 is a really nice charger, it has a back-light that turns itself off, all you need to do is to touch any of the buttons and the back-light comes back on again. It's default charge rate is 200ma and of-course you can change that on each of the 4 cells individually OR you can also easily select to have all 4 cells the same charge rate such as 1000mA without having to manually set each channel and yet you can still set each channel to be different if you wish. The charger also contains 6 sensors for overheating, one for each of the 4 battery slots and 2 additional sensors for the controller board. The charger can also dynamically Test the internal resistance of each battery, thus one of the reasons they included the C & D cell adapters with the Charger.

It looks to me that Yes they have been paying attention to the Marketplace and blended together the features of the C9000 & BC1000 with desired features such as the back-light times outs, etc. I Own the BC1000, C9000, IQ-328 and the BM200 and I simply love the BM200; it's my go to charger now.


----------



## Rexlion

*Re: SOMETHING COMPLETELY NEW For the Maha MH-C9000: Custom C/D Adapters!*

My adapters came today and I tried them in bays 1 and 4 of the Maha... nada, zilch, nothing happened. Took them out and put them back in several times, tried having the D cell in the adapter when it's inserted, tried adding the D afterward. Then I tried bay 2 and voila, it's working. But I can only do one D at a time that way. I could not see anything that could have been preventing contact in bays 1 and 4, but there must be something.


----------



## Viking

*Re: SOMETHING COMPLETELY NEW For the Maha MH-C9000: Custom C/D Adapters!*

Maybe you need to cut some plastic off. I read the following in a review about the BM200 , and the adapters placed onto the MH-C9000:




> By the way, those adapters can also fit onto the MH-C9000, but I need to shave off 1-2mm of plastic from the charger’s positive terminal, in order to make electric contact.
> 
> http://searchproductreviews.com/nle...r-analyzer-tester-nimh-nicd-aaa-aa-c-d-cells/


----------



## TakeTheActive

*Re: SOMETHING COMPLETELY NEW For the Maha MH-C9000: Custom C/D Adapters!*



picrthis said:


> You can buy ready made adapters for C & D cells that fit the C9000.


*picrthis*,

Based on the following comments from *Rexlion* and *Viking*, would you please add 3 more photos to your original post (QUOTEd above):
.

The POSITIVE end of the adapter, head on, with the adapter upright, as positioned in the C9000.
.
The NEGATIVE end of the adapter, head on, with the adapter upright, as positioned in the C9000.
.
The BOTTOM of the adapter, with the adapter upside down, to gauge the distance the metal contacts extend beyond the plastic housing.
My guess is that these adapters may be similar to the RadioShack 'N-to-AA' adapters I have. I needed to use a tiny screwdriver to slightly bow the contacts away from the plastic so that they would reach the contacts on my chargers *BEFORE* the plastic shoulders surrounding them contacted the plastic shoulders on the chargers.

Just a thought. :thinking:

Thanks! 



Rexlion said:


> *My adapters came today and I tried them in bays 1 and 4 of the Maha... nada, zilch, nothing happened*...





Viking said:


> *Maybe you need to cut some plastic off. I read the following in a review about the BM200 , and the adapters placed onto the MH-C9000*:


----------



## TakeTheActive

*Charging At Below 0.5C...*



Russel said:


> Haven't seen you post in a while TakeTheActive! *It's good to see you active!*


Thanks! :wave:

As I probably said here (DEFINITELY said on other forums where I've created lengthy FAQs), I usually immerse myself in a topic for several months at a time. Then, when I feel that I've learned, and shared, as much as I can, I move onto my next topic of interest. I'll LURK for a while, but, all you see are the same old asked-and-answered questions being asked and answered once again by the patient gurus. So, eventually daily drops to weekly drops to monthly, etc...

Currently I'm learning about HTPCs. Since my ReplayTV 5XXXs with NTSC/Analog tuners are now relying on Magnavox DVDRs feeding them through their Line Inputs (one DVDR currently dedicated to one RTV - CBS, NBC, ABC), when the HDD in my WinXP Home PC died, I started using my 'Backup' (i.e. bought ON SALE waiting for the need to put into service) Vista Home Premium PC with Windows Media Center and SiliconDust HDHomeRun HDHR3-US Dual Tuners. Even had to buy a couple of HDTVs!  But, since WMC records in a proprietary format (.dvr-ms for Vista; .wtv for Win7), I can't view the recordings on a 'Plain Vanilla' Media Streamer. Thus, now I'm learning about third party 'WMC-replacement' software that records in .TS format.



Russel said:


> ...*The 2.5 and 3X is referring to the number of regular charge cycles needed to fully charge a completely depleted D cell. During the normal charge cycle, the MH-C9000 has a charge capacity limit of something like 4000 mAh. So, the charger would have to be restarted a couple or three times to completely charge an 8000 mAh to 10000 mAh D cell*...


The first time I read this, I immediately thought of *jtr1962's* entry in my FAQ. Total mAh INPUT is dependent on the Charge Rate - i.e. the lower the rate, the longer the time / percent overcharge required. For simplicity, using a 10,000mAh cell, charging @ 0.5C / 5,000mA takes about 1.2 x 10,000mAh, or 12,000mAh. But if you lower the Charge Rate to 0.2C / 2,000mA may take ~15,000mAh or more. Or you could charge @ the Break-In Rate of 0.1C / 1,000mA for 16 hours, again still limited by the 4,000mAh per session. Now we're at 4X. 



Russel said:


> ...*Of course, that is not the case when using the break in mode. I only use the MH-C9000 for testing and running D cell through a break in cycle. I use a MH-C808M to charge them.* The MH-C808M charges at a pulsed 2000 mA charge current, and the Accuevolution D cell that I have recommend charging at 2000 mA. So far my old D cells have been working very well.


That's why I bought the magnets - Break-In! :twothumbs For charging, I use an old RadioShack @ 2500mA.

BTW, today I learned that:
.

Panasonic bought Sanyo
.
There is now a 3rd generation Eneloop
.
Japanese girls don't like the color of the new Eneloops


----------



## Viking

*Re: Charging At Below 0.5C...*

personally I use these magnet based adapters , produced by forum member Martin White. They fit the MH-C9000 perfectly. And because they are magnet based , they will fit any battery as well. But I admit those adapters picrthis posted really look nice 



http://www.cpfmarketplace.com/mp/sh...ion-into-an-18650-charger-(Pila-IBC-or-other)


http://www.martinwhite.name/images/July_10_2011/IMG_6650.JPG

Your images are oversize, when you post an image please remember Rule #3 

Rule #3 If you post an image in your post, please downsize the image to no larger than 800 x 800 pixels.

*Please resize and repost.* - Thanks Norm


----------



## picrthis

*Re: SOMETHING COMPLETELY NEW For the Maha MH-C9000: Custom C/D Adapters!*



TakeTheActive said:


> *picrthis*,
> 
> Based on the following comments from *Rexlion* and *Viking*, would you please add 3 more photos to your original post (QUOTEd above):
> .
> 
> The POSITIVE end of the adapter, head on, with the adapter upright, as positioned in the C9000.
> .
> The NEGATIVE end of the adapter, head on, with the adapter upright, as positioned in the C9000.
> .
> The BOTTOM of the adapter, with the adapter upside down, to gauge the distance the metal contacts extend beyond the plastic housing.
> My guess is that these adapters may be similar to the RadioShack 'N-to-AA' adapters I have. I needed to use a tiny screwdriver to slightly bow the contacts away from the plastic so that they would reach the contacts on my chargers *BEFORE* the plastic shoulders surrounding them contacted the plastic shoulders on the chargers.
> 
> Just a thought. :thinking:
> 
> Thanks!



I'm not having the issue, but I understand some might have a slight issue which is easily resolved with no cutting on the plastic on your Charger which I would never do. The positive contact can be 20 mil too high, crimp the rounded top off of that and all is well.


----------



## Viking

*Re: SOMETHING COMPLETELY NEW For the Maha MH-C9000: Custom C/D Adapters!*

I must admit I never had heard about the BM200 charger before now. It seems to have some advances , as well as some disadvantages compared to the MH-9000. The advances are the very high 20.000 MAh charging limit , and the internal resistance test ( I especially like this feature  ). 


Maybe I will add this charger to my MH-9000.


----------



## Rexlion

*Re: SOMETHING COMPLETELY NEW For the Maha MH-C9000: Custom C/D Adapters!*



Viking said:


> Maybe you need to cut some plastic off. I read the following in a review about the BM200 , and the adapters placed onto the MH-C9000:



Thanks, Viking. I could not visually see any problem, and the positive contact seemed to click into place nicely. But tonight I used a jackknife to shave a small amount of plastic off the Maha just above the contacts on bays 1 and 4, and now both adapters are activating the charger. Which is great, because doing just one D cell at a time was getting tedious... they can take a while on refresh/analyze mode. 

Sorry I did not see the later posts about crimping the contact on the adapter, I can see how that would work too. But the amount I had to remove from the charger was so tiny, I don't feel bad about it.

BTW, my first D cells through the Maha were 4 old, crappy "CTA" 12,000 mAh that I got with a used MP light maybe 3 years ago. I was curious to see just _how_ bad they were, and now I know. Readings were 7370, 3773, 1362, and (believe it or not) 564!


----------



## Mr Floppy

picrthis said:


> are advertised by the seller as such too.
> 
> http://www.ebay.com/itm/BM200-Batte...473?pt=US_Battery_Testers&hash=item4d0c4d16b9



Hmm, they may have also ripped off the information datalucis perhaps?
http://web.archive.org/web/20130526062721/http://datalucis.com/


----------



## picrthis

Mr Floppy said:


> Hmm, they may have also ripped off the information datalucis perhaps?
> http://web.archive.org/web/20130526062721/http://datalucis.com/



No they didn't  they are in-fact the same person.


----------



## N8N

I got mine the other day but still was breaking in some AAs... finally got my old "CTA" brand C-cells out, had to shave a little plastic off one of the adapters to get it to fit into the charger deep enough but other than that no probs... now just need to wait another day and find out if I need to order larger cells as well as more AAAs... anyway, good find, this allows me to get rid of my crappy Energizer charger and use my C9000 until I pop for larger good charger

Edit: apparently my old "5500 mAh" cells are actually around 2800 mAh... but then again even though I charged them in my old Energizer charger they only gave me about 1100 mAh before I ran them through the break in cycle so they must have been consistently undercharged the whole time I was using them... no wonder I was suspicious of their runtime.


----------



## Mr Floppy

picrthis said:


> No they didn't  they are in-fact the same person.



I see the customer support statement now. I was wondering what happened to that company. 

It also mentions that the charger is the only one that has the internal resistance function, but doesn't the C9000 have something that you can use to work out the internal resistance?


----------



## Paweł

Could you help me answer if my MH-C9000 is broken?
When I put discharged aku, set "charge", next I set e.g. 500mA and Enter. But it not start charge but ask me for select "mode".
I repeat steps and after 2 seconds is exactly the same: select mode "screen" and so on.

When I put really good aku (super new eneloop) everything is OK.
One of my problem acu is one of the just finished "BreakIn Mode". Problem acus are GP, Energizer, Tronic and other.

When I put any of these problem acu to BC-700 it starts with no problem.

Best regards
Paweł.


----------



## SilverFox

Hello Pawel,

Welcome to CPF.

It sounds like you may have a connection problem. This is most often seen with AAA size batteries.

Tom


----------



## Paweł

SilverFox said:


> Hello Pawel,
> Welcome to CPF.
> It sounds like you may have a connection problem. This is most often seen with AAA size batteries.
> Tom


Thank you for your answer.
I have this problem with some AA and AAA.
And I have some AA and AAA this problem dosn't exist.

What is strange, o few of them, just passed brake-in process and was full charged.
I expect "done" after a moment of charging such akus rather then "select mode dead cycle", am I right?

Best regards
Paweł


----------



## SilverFox

Hello Pawel,

If the connection is broken the charger will start over. This will show up as if you just put a cell in to charge rather than showing Done.

I have modified my chargers by adjusting the contacts to make better contact. You have to be careful not to break anything but the results limit this problem.

Tom


----------



## mactavish

*Re: Maha MH-C9000 SUPPORT - BM200 Charger Info*

Hello CPF members. I've been a long time lurker, learning about various flashlights, etc. I finally decided to become a member, as I thought I would share my recent experience with a new NiMh battery charger that I see mentioned in this thread. Since it poses a potential for overheating and therefore what I see as a possible danger, I just joined the CPF forums.


I'm posting this here, in this thread, since the "BM200" has been mentioned in above posts. While I have some experience with my Pila LiMN charger, last week I decided to get into buying and charging MiMH batteries. Some for use in my flashlights, but mostly for all my other devices, many of which are simple remote controls, for TV's etc. I was tired of finding leaky Duracells, and the cleanup of those remotes, switching to Energizers was not confidence inspiring either. Some of these batteries were new, less then a year old, with expiration dates, years from now. Even though I was pretty sure they were not "knock-offs", it's hard to tell these days. I invested in a bunch of the latest Eneloop 1800's, AA/AAA's as well as 4 Tenergy "Centura" 8000 mAh D-Batteries.


So I began my "charger" research here, and found very little information on the fairly new BM200 charger, this should have been a tip off. I did find years worth of posts on the Maha-Powerex MH-C9000 charger. I read an "originally" very positive 5 star review, from a "top 10 reviewer" on Amazon for the BM200, saying it combined the best features of the C9000, and the "La Crosse BC100". 


Last line of the review sold me: "Over all, I consider the BM200 a superior advanced charger compared to BC1000 and MH-C9000."


So I bought the BM200, and began charging batteries on it, noticing the batteries felt very HOT to the touch. After a few more days of reading, I determined that while not scientific, a finger touch of a charging battery, could of course be "warm", but should not be hot. This was alarming.


I continued a conversation, in the user "comments" section for the BM200, and in a few days, the original reviewer returned, and did more testing on this charger, and in the end discovered with his temperature reading equipment, that indeed there was an overheating problem with this unit, he decided to reduce his original rating from 5 stars to 3, and update his review (not mentioning me at all, not that I care), and after finishing my own "comments" postings, I put up my final review for others, with a 1 star rating. There was another new buyer that returned his BM200 for the same overheating issue. Amazon was good and quick with my refund, and I purchased the MH-C9000, which I should have in the first place, simply because of it's long track record, and it's large presence in the CPF forums. I took a gamble that perhaps a newer device might have some new technology and be an upgrade, but after having both here at the same time, running side by side tests, the build quality alone between the two, was very apparent, as well as seeing an actual company behind the Maha unit. Not just another no-name chinese import. So I learned a lot in the process, and thought I would share it here, for anyone considering this newer charger, as well as a "heads-up", for anyone that bought and owns one. The quality control from unit to unit could be an issue to be aware of. 


If you want learn more, with detail, the link below will take you to the Amazon BM200 product page, and from there, just click on the "comments", below the original review, (NOT the "customer reviews"), there are over 100 comments now, my posts in the "comments" section, beginning on page #4, will be obvious as it relates to this post, as well as my username "mactavish". Hope someone finds this useful.


LINK: http://www.amazon.com/dp/B00CWRU1QC/?tag=cpf0b6-20


----------



## mactavish

*Re: SOMETHING COMPLETELY NEW For the Maha MH-C9000: Custom C/D Adapters!*



picrthis said:


> I'm not having the issue, but I understand some might have a slight issue which is easily resolved with no cutting on the plastic on your Charger which I would never do. The positive contact can be 20 mil too high, crimp the rounded top off of that and all is well. In the enclosed pic the one on the right has been reworked, it may be hard to see because it's only 20 mils difference.
> 
> http://i832.photobucket.com/albums/zz245/electronman5/CDadapters.jpg
> 
> I hope that helps.
> 
> Your images are oversize, when you post an image please remember Rule #3
> 
> Rule #3 If you post an image in your post, please downsize the image to no larger than 800 x 800 pixels.
> 
> *Please resize and repost.* - Thanks Norm



Thanks for the very detailed photo. I thought I might have to do this "mod", or the one mentioned earlier in this thread of removing some plastic on the MH-C9000 charger itself. But before doing anything, I took the two "D" adapters that came with the BM200 (not the aftermarket ones available on ebay, though they may be the same?), and placed them into the Maha charger, they clicked in just fine, and the charger recognized the 2 Tenergy 8000 mAh LSD batteries. Comparing my two adapters to the photo in your post, it seems there is NO extra metal to even bend in. Perhaps they made an improvement or the ones included with the BM200 are different, though one might assume there is only one factory making these adapters in the first place? So far, working fine. I would still assume, that using these adapters, still bypasses any over temp sensors the C9000 has, as these adapters ride higher up on the charger, so one must rely on the timer and voltage cutoffs when charging "D" batteries in a charger that does not officially support this. I only have 4 "D" batteries I need to keep in an emergency LED "Coleman" light, I would use in power blackouts. The rest of my batteries are AA/AAA.


----------



## mactavish

*Re: SOMETHING COMPLETELY NEW For the Maha MH-C9000: Custom C/D Adapters!*



Russel said:


> [/LIST]
> 
> Haven't seen you post in a while TakeTheActive! It's good to see you active!
> 
> The 2.5 and 3X is referring to the number of regular charge cycles needed to fully charge a completely depleted D cell. During the normal charge cycle, the MH-C9000 has a charge capacity limit of something like 4000 mAh. So, the charger would have to be restarted a couple or three times to completely charge an 8000 mAh to 10000 mAh D cell. Of course, that is not the case when using the break in mode. I only use the MH-C9000 for testing and running D cell through a break in cycle. I use a MH-C808M to charge them. The MH-C808M charges at a pulsed 2000 mA charge current, and the Accuevolution D cell that I have recommend charging at 2000 mA. So far my old D cells have been working very well.



Read everything I could find on using the "D" Adapters with my new MH-C9000, trying to charge the only 4 "D" batteries I own, the Tenergy LSD 8000 mAh. While the general consensus is to use the "Break-In Mode", I just didn't want to wait the 4 days it would take to do both sets of (2). So just for fun, and as a test I put the C9000 on the basic "Charge Mode". 

(Charge Rate = 2000 mA = .25C) 1st Charge = 2:15 min. stops at 4,000 mAh - 2nd Charge 2:15 mins, 1.4.0 Volts. - 3rd Charge 30 mins. 1.4.0 Volts, - 600 mAh, then DONE! 5 hours total.

Downside, the resting voltage on the charger, these batteries never show more then 1.40 volts, as opposed to the 1.46-1.48 resting voltages I get when using the R&A mode on all my AA/AAA Eneloops. The other downside is when using the regular "charge mode", you don't get to see the total mAh's, since there is NO discharge cycle. While I only bought these 4 "D" batteries to keep in a Coleman LED emergency light, so I did not want to buy another charger just for these 4 "D" bats, they may be fine at the 1.40 voltage, but I guess I'm going to have to break down, and put them on the "Break-In Mode", if I really want to know their capacity and hopefully get more voltage into them at the end. I'm new to both NiMH batteries and chargers.

Let me take a second to thank ALL the members for their posts, I went back to posts from 2007 regarding usage of the MH-C9000 charger. While there of course are some conflicting comments, I saved many posts in a document to refer to, and just have to weed out, some of the older data that may no longer apply, no easy task for a newbie!

Does this make sense?


----------



## Russel

*Re: SOMETHING COMPLETELY NEW For the Maha MH-C9000: Custom C/D Adapters!*



mactavish said:


> [...]
> (Charge Rate = 2000 mA = .25C) 1st Charge = 2:15 min. stops at 4,000 mAh - 2nd Charge 2:15 mins, 1.4.0 Volts. - 3rd Charge 30 mins. 1.4.0 Volts, - 600 mAh, then DONE! 5 hours total.[...]



That looks about right, given the 4 Ah limit that the C9000 has in standard charge mode. Keep in mind that you can top off a little more by leaving the cells for a couple hours after "done."

If you really want to get a reasonably accurate capacity reading for your D cells you do need to use the break in mode. Be sure to set up your charging station in a safe manner, especially because of the long time it will take. I like to set up on an old kitchen counter remnant that's about 2' by 3' of stone.


----------



## mactavish

*Re: SOMETHING COMPLETELY NEW For the Maha MH-C9000: Custom C/D Adapters!*



Russel said:


> That looks about right, given the 4 Ah limit that the C9000 has in standard charge mode. Keep in mind that you can top off a little more by leaving the cells for a couple hours after "done."
> 
> If you really want to get a reasonably accurate capacity reading for your D cells you do need to use the break in mode. Be sure to set up your charging station in a safe manner, especially because of the long time it will take. I like to set up on an old kitchen counter remnant that's about 2' by 3' of stone.



Thanks "Russel".

I've been following the general advice of leaving all my Eneloops AA/AAA on the charger for an additional 2 hours after "DONE" appears "trickle mode", as it's been mentioned the cutoff on the later model C9000's is about 1.47 volts. Didn't realize that might apply to the Tenergy D's after 3 "charge" cycles. I keep the charger on a fireproof surface with a smoke detector above it, but the approx. 39 hours for "break-in" mode is a bummer, as I prefer to be around when charging bats. I am happy however that I returned the BM200 for "overheating batteries", and got this C9000, have not noticed the batteries getting anything more then warm in all my charging so far. 

Using the AA to "D" adapters is a slight concern as I assume they way they ride high up in the charger, negates any built-in charger high temperature sensor cutoffs, and all that's left for the charger brain, is the voltage cutoff point.

Thanks again, I've saved many of your posts regarding charging for my "notes"!


----------



## mactavish

*Re: SOMETHING COMPLETELY NEW For the Maha MH-C9000: Custom C/D Adapters!*

Not sure what's going on with my charging of the Tenergy LSD 8000 mAh "D" batteries. I decided to put them on "Break-in Mode" on the MH-C9000. 2 "D's", one in each adapter. I think I messed up on the one in slot 2, so I began a discharge on it, and then a manual charge, basically had to bail out on the 39 hour BI mode. But the one is slot 1, was going through it's cycles, and at 15 hours from start of BI mode, it was on it's "charge" cycle, but looking at the charger, it stated 12.4 mAh's, that's 12,400 and the battery felt HOT, so I removed it. I'm beginning to wonder if using these adapters on a charger that is not designed specifically for "D" charging is a perhaps a bad idea in the first place. After all the reading I did, it seemed safe to try the BI mode, but this battery felt very hot, and that number way too high. 

Any thoughts?


----------



## Russel

*Re: SOMETHING COMPLETELY NEW For the Maha MH-C9000: Custom C/D Adapters!*

The break in mode charges the cells at 0.1C for a fixed time of 16 hours. That is 1.6 times the capacity of the cell. NiMH cells at the 0.1C charge rate can tolerate this over charge because it is at a low rate, with respect to capacity, and the charge efficiency is lower at such a low rate. (Charge efficiency at low rates is still a debated subject.) So, it is normal for the cell to be warm after 15 hours of the 16 hour charge.


----------



## mactavish

*Re: SOMETHING COMPLETELY NEW For the Maha MH-C9000: Custom C/D Adapters!*



Russel said:


> The break in mode charges the cells at 0.1C for a fixed time of 16 hours. That is 1.6 times the capacity of the cell. NiMH cells at the 0.1C charge rate can tolerate this over charge because it is at a low rate, with respect to capacity, and the charge efficiency is lower at such a low rate. (Charge efficiency at low rates is still a debated subject.) So, it is normal for the cell to be warm after 15 hours of the 16 hour charge.



Thanks! I guess I panicked when I saw that HUGE mAh number. The manual mentions what you said as well, but since the battery felt more then "warm", as in HOT, I stopped. I wonder how high the mAh figure will go if I left it on the charger. I guess I'm going to have to discharge and try again, though the temperature of the battery can't be good for it for long periods. When I used the Break-In mode on the AAA's then never got hot. 

Then again, maybe I should just use the normal "charge" mode, and put all 4 in the LED Coleman light, and see how long it runs, then charge em again, and put it away.

Thanks Russel!


----------



## Mr Happy

*Re: SOMETHING COMPLETELY NEW For the Maha MH-C9000: Custom C/D Adapters!*



mactavish said:


> Thanks! I guess I panicked when I saw that HUGE mAh number. The manual mentions what you said as well, but since the battery felt more then "warm", as in HOT, I stopped. I wonder how high the mAh figure will go if I left it on the charger. I guess I'm going to have to discharge and try again, though the temperature of the battery can't be good for it for long periods. When I used the Break-In mode on the AAA's then never got hot.



If you run a break-in cycle on the D cell and enter 8000 mAh as the capacity, then the charger will try to charge the cell at 800 mA for 16 hours (nothing wrong with this, it is what the break-in cycle is supposed to do).

However, 800 mA is rather a large charging current compared to the, say, 200 mA that an AA cell would get. It is often recommended to limit the maximum charging current on a D cell to 1 A or 2 A or so, and 800 mA is a significant portion of this. The D cell is also rather larger than an AA cell with a smaller surface area to volume ratio, so it is harder for the heat to escape.

So it does not surprise me that the D cell would get hot during the break-in cycle. I have not tested D cells myself this way, so I have no direct comparison to make. This is just an estimate.

If you try running a break-in cycle again, you might try entering a capacity of 6000 mAh instead of 8000 mAh and see if the batteries stay cooler.

Also bear in mind there is nothing to stop you running a discharge on the C9000 to measure the capacity of your D cells. I don't think there is a limit on the maximum capacity for discharge.

Lastly, you can use the break-in cycle to run a "manual charge" on a battery. For example, proceed as for a break-in cycle, but enter a battery capacity of 20,000 mAh. This will cause the charger to charge at a rate of 2000 mA for 16 hours. However, you don't have to let it run for this long. Let it run for 4 hours and watch the battery carefully. When the voltage on the display stops climbing and when the battery starts to get very warm, manually stop the charge. *Do not leave this to run unattended or bad things will happen if you miss the stop time!*


----------



## mactavish

*Re: SOMETHING COMPLETELY NEW For the Maha MH-C9000: Custom C/D Adapters!*

Thanks "Mr. Happy", I save many of your posts as well, in my home made "Battery Info Manual". More great info, and I like the extra option, for "manual charge" using BI mode, I'll be careful. I feel better reading your post about the HEAT now, at first it was alarming, reminded me of why I returned the BM200 charger, it overheated AA batteries, this C9000 never gets those hot at all.

In your opinion, does keeping these Tenergy "D" batteries on "trickle charge", they way you have to with the "Eneloop" brand, after the C9000 says "DONE", to get from 90% to 100% charged, advice APPLY? That "note" seemed to apply mostly to Eneloops on the C9000 charger. Or since they are so dense, it would take forever, and be a waste of time? They seem to top out at 1.40 volts, where you can get the Eneloops to about 1.47 volts if left on the charger for the extra 2 hours after "DONE", but the AA/AAA are so much smaller.

Thanks again guys/gals for the EDUCATION!


----------



## Mr Happy

*Re: SOMETHING COMPLETELY NEW For the Maha MH-C9000: Custom C/D Adapters!*

The question of 1.40 volts or 1.47 volts depends on the battery technology. Some of the "older" battery technologies such as you might find in those Tenergy cells will top out at lower voltages than the new batteries like Eneloops. Eneloops in particular go to much higher voltages than some other NiMH cells.

So it may be that the Tenergy cells will never go to 1.47 volts no matter how much you charge them.


----------



## mactavish

*Re: SOMETHING COMPLETELY NEW For the Maha MH-C9000: Custom C/D Adapters!*

OK, I get it. Right now, with of a bit of a discharge already, I'm just putting them in the standard charge mode, until they say DONE. I'll let them sit and then read the voltage with a meter. I've played with almost every charging mode at this point, and have learned a lot. In 6 months I'll take them out of the emergency LED Coleman lantern and re-evaluate them. It's certainly shown me that AA/AAA charging is a lot simpler, then again that's what the C9000 is really designed to do in the first place. If I had more "D" batteries I would buy a separate charger for them. Thanks again for taking your time to help a newbie!


----------



## SilverFox

Paweł;4227028 said:


> Thank you for your answer.
> I have this problem with some AA and AAA.
> And I have some AA and AAA this problem dosn't exist.
> 
> What is strange, o few of them, just passed brake-in process and was full charged.
> I expect "done" after a moment of charging such akus rather then "select mode dead cycle", am I right?
> 
> Best regards
> Paweł





Hello Pawel,

I just ran into this myself.

I have a solar light that rarely gets used. I happen to put a crap battery in it just to see how crappy it would get.  I used it a couple of times and ran the battery down. When I put it into the C-9000 charger it would reset again and again.

I moved the battery to a different charger that would allow me to monitor voltage under a low current charge. What I found was that as soon as any charging current is applied, the voltage ramped up to around 3.4 volts.

I believe the Maha charger has a high voltage cut off of around 2.0 volts, so as soon as it applied some current to check the condition of the battery the voltage ran up beyond its cut off and it shut down. As soon as the current is stopped, the voltage of my battery dropped to about 1.4 volts. The Maha charger sees this voltage and recognizes it as a cell that can be charged. 

As this cycle repeats you continue to get the reset condition that you experienced.

The bottom line is that my crap cell got crappier and is now in the recycle bin.

Tom


----------



## picrthis

*Re: SOMETHING COMPLETELY NEW For the Maha MH-C9000: Custom C/D Adapters!*



mactavish said:


> Thanks! I guess I panicked when I saw that HUGE mAh number. The manual mentions what you said as well, but since the battery felt more then "warm", as in HOT, I stopped. I wonder how high the mAh figure will go if I left it on the charger. I guess I'm going to have to discharge and try again, though the temperature of the battery can't be good for it for long periods. When I used the Break-In mode on the AAA's then never got hot.
> 
> Then again, maybe I should just use the normal "charge" mode, and put all 4 in the LED Coleman light, and see how long it runs, then charge em again, and put it away.
> 
> Thanks Russel!



Funny how you complained about heat problems with the BM200 too and now the C9000, looks like you have a lot of learning to do yet. It's a shame you are doing the "learning" at the expense of the Seller of the BM200 danaco, because you returned the BM200 for "heat issues" and You kept the C & D adapters and are now using them on the C9000 and having a few issues too; I really hope danaco goes to Amazon and shows them this post as further proof and gets his money back from your fraud. You received a full refund including overnight shipping and kept the C & D adapters with the full intent of using them on the C9000, that's no mistake, it's clearly fraud.


----------



## mactavish

*Re: SOMETHING COMPLETELY NEW For the Maha MH-C9000: Custom C/D Adapters!*

I still own a BM200, since it's one I can't return, you are welcome to it. Continue on, you amuse me.


----------



## picrthis

*Re: SOMETHING COMPLETELY NEW For the Maha MH-C9000: Custom C/D Adapters!*

Here's the REAL story;

http://www.danaco.net/BM200.html


----------



## mactavish

*Re: SOMETHING COMPLETELY NEW For the Maha MH-C9000: Custom C/D Adapters!*

Yes, spelling aside, it's a fantastic "story", nice work.


----------



## Illumination

*Re: SOMETHING COMPLETELY NEW For the Maha MH-C9000: Custom C/D Adapters!*

How hot should a cell being charged. I charged 4 2650 MAH Duracells last night at 700; woke up surprised they were still charging and touched them. They were really hot so I pulled them. Is this normal? It has been a while since I have used my charger but don't ever remember getting cells hot to the touch. Thanks.


----------



## bbb74

*Re: SOMETHING COMPLETELY NEW For the Maha MH-C9000: Custom C/D Adapters!*



Illumination said:


> How hot should a cell being charged. I charged 4 2650 MAH Duracells last night at 700; woke up surprised they were still charging and touched them. They were really hot so I pulled them. Is this normal? It has been a while since I have used my charger but don't ever remember getting cells hot to the touch. Thanks.



That's called a missed termination and you've damaged or killed the batteries. Why did you charge at 700mAh? Its too low for cells of that capacity and it increases the risk of a missed termination. I'd be charging those cells at 1000mAh *minimum*, more like 1200 if you are having termination issues with them.


----------



## He's Dead Jim

*Re: SOMETHING COMPLETELY NEW For the Maha MH-C9000: Custom C/D Adapters!*

if i make my own battery adapters, do i have to jump out the temperature sensors as well?

i have 6 different size batteries and none of them are AA or AAA.


----------



## SilverFox

*Re: SOMETHING COMPLETELY NEW For the Maha MH-C9000: Custom C/D Adapters!*

Hello He's Dead Jim,

Welcome to CPF.

I don't think anyone worries about the temperature sensors. You are moving the cells away from the charging circuit so that source of heat is not a concern. If your cells get hot enough to melt the adapters with the maximum charge rate of 2 amps you most likely need some new cells.

Tom


----------



## Yamabushi

*Re: SOMETHING COMPLETELY NEW For the Maha MH-C9000: Custom C/D Adapters!*



He's Dead Jim said:


> i have 6 different size batteries and none of them are AA or AAA.



I have to ask ... other than C and D, what other sizes of 1.2 V NiMH do you have and what devices use them?


----------



## donn_

Does the 9000 default to 1A charge, no matter what size cell is put in it?


----------



## N8N

yes, all it knows is whether a cell is present and it detects somehow NiMH or NiCd. Other than that you have to tell it what to do.


----------



## donn_

Thanks.

Another flaw in an almost perfect charger.


----------



## papershredder

donn_ said:


> Thanks.
> 
> Another flaw in an almost perfect charger.



Yeah, I don't know what they were thinking?
My power went out for half of a second the other day, which happens rarely where I live. 

Two things I had to deal with:

Motor in AC unit started acting up until I gave it a proper power cycle. It was making some weird noises. 
Maha C9000 charger decided it was time to charge. :shakehead


----------



## N8N

The latter I deal with by leaving it plugged into a UPS... which reminds me, I need to box it up & send it back, the wall wart died anyway 

Sent from my XT897 using Tapatalk 4


----------



## N8N

Discovered something today. Got my replacement C9000 in the mail which is good because I had some cells that I'd actually run out of juice and needed to charge, and also I bought some more. Among the "more" that I bought were two Tenergy D cells, which are rated at 8000 mAh. They're breaking in right now, and I discovered something... they'll charge at 0.1C fine (800mA) but they are discharging at only 1A - whereas 0.2C would be 1600 mA. I guess the maximum discharge current of these things must be 1A so anything over 5000 mAh will take even longer than the usual 39 hours to break in! Not sure how the lower discharge current will affect the capacity reading, I guess I would assume that it would artificially inflate it. Certainly using the C9000 on C or D cells regularly would be quite the PITA, I'm looking for another charger that will handle them for regular charging, but then again I don't need a whole lot of the larger sized cells.

I was a little disappointed, there wasn't a whole lot of charge left in these cells per the pre-break in discharge, only around 2000 mAh. Couldn't see a date on them either though. I'll take 'em back if they don't test in spec though.

Edit: they must have just sat around for ages and ages and might not have been charged up fully from the factory... I started them at different times as one of them discharged first and I only need one for immediate use; that one has discharged 4500 mAh and still decent voltage. I'll try to remember to test the charge in the one that I won't be using if I haven't found a home for it in 3 months or so.


----------



## Mr Happy

N8N said:


> they are discharging at only 1A - whereas 0.2C would be 1600 mA.



The C9000 has a maximum charge current of 2000 mA and a maximum discharge current of 1000 mA.


----------



## DarkMorford

Hi, all! I ordered my MH-C9000 from Amazon back in April (it's the 0L0HA revision), and immediately started running all my batteries through it, weeding out all the ones that were too far gone to keep a charge anymore. It worked great, and I absolutely loved it!

I've only used it on and off since then, but about a month ago I noticed it being reluctant to charge more than one cell at once. I went out and bought some brand-new batteries (Sony CycleEnergy 2500 mAh AA cells), and while the C9000 will happily charge one at a time, as soon as I insert a second battery and select the charge cycle—using the default 1000 mA charge rate—the thing resets and tries to start over. It then continues resetting itself non-stop until I take one of the cells out. It goes without saying that 3 or 4 cells produces the same behavior.

Did I just end up with a bum charger? Is there any way to fix this?


----------



## Power Me Up

It could be that the power supply is failing. If you've got access to another power supply that provides a regulated 12V output and the same plug and polarity, you could try it with that.

A few questions:

Does it work with any single slot charging? Does it work if you select a 2000 mA charging rate?


----------



## N8N

I ordered mine in early May, same rev, and my power supply completely died between one use and the next (probably a week or two.)

Do you have a meter and can you measure the output of the wall wart?

Also, if you have the cig lighter adapter you could try that too. In fact I am thinking of ditching the wart and wiring a harness straight from the battery expansion connector of my UPS to the power plug on the C9000 that way less loss and more reliability... since I have to have it plugged into the UPS anyway it only makes sense


----------



## DarkMorford

Unfortunately, I do not have another compatible power supply, either AC or DC. The supply I have measures exactly 12 V unloaded, but I don't have a way to measure it under load. Any of the four charging lanes work, but ratcheting the charger up to a full 2000 mA charging rate causes it to reset itself.

Starting to sound to me like it is the supply, but I don't know how to test it for sure.


----------



## Planz

donn_ said:


> Does the 9000 default to 1A charge, no matter what size cell is put in it?



That is one of the irritating aspect of the Maha. 
They have serious competition now and this will drive them to update their design.

http://www.candlepowerforums.com/vb/showthread.php?366538-Anyone-have-the-SkyRC-NC2500-charger


----------



## Power Me Up

DarkMorford said:


> Unfortunately, I do not have another compatible power supply, either AC or DC. The supply I have measures exactly 12 V unloaded, but I don't have a way to measure it under load. Any of the four charging lanes work, but ratcheting the charger up to a full 2000 mA charging rate causes it to reset itself.
> 
> Starting to sound to me like it is the supply, but I don't know how to test it for sure.



Definitely sounds like the power supply to me.

Try calling Maha directly - they're pretty good with their after sales service!


----------



## NeoLoop

DarkMorford said:


> Hi, all! I ordered my MH-C9000 from Amazon back in April (it's the* 0L0HA revision*), and immediately started running all my batteries through it, weeding out all the ones that were too far gone to keep a charge anymore. It worked great, and I absolutely loved it!



Hi all n hi DarkMorford, 
where i can see the production code version (revision), is that on the box or in the unit ?

is anyone can help me to post the picture here, to show me where side I can find n see the code version of MHC-9000, so i can make sure buy the recent ones

what the new feature added untul now in new revision since 0H0EAB (May 2008) ?
I ask my supplier, they give me the production code MHC-9000-0000GE, what 0000GE mean ? 

AFAIK :
_* Presumably the first two characters are the year - 0F means 2006, 0G is 2007, 0H is 2008, and so on.
The next two characters are the month - 0B is 02 or February, 0I is 09 or September, AB is 12 or December, 
although more recently a 0K - "011" or November - has also been reported. 
The last two numbers, or more recently single letter, appear to be the batch number from that month.
_
All, would you help me replay quick please.. because i want to buy it in next few days, n stock is limited only 2-4 unit ready

thanks all


----------



## samgab

NeoLoop said:


> Hi all n hi DarkMorford,
> where i can see the production code version (revision), is that on the box or in the unit ?
> 
> is anyone can help me to post the picture here, to show me where side I can find n see the code version of MHC-9000, so i can make sure buy the recent ones
> 
> what the new feature added untul now in new revision since 0H0EAB (May 2008) ?
> I ask my supplier, they give me the production code MHC-9000-0000GE, what 0000GE mean ?
> 
> AFAIK :
> _* Presumably the first two characters are the year - 0F means 2006, 0G is 2007, 0H is 2008, and so on.
> The next two characters are the month - 0B is 02 or February, 0I is 09 or September, AB is 12 or December,
> although more recently a 0K - "011" or November - has also been reported.
> The last two numbers, or more recently single letter, appear to be the batch number from that month.
> _
> All, would you help me replay quick please.. because i want to buy it in next few days, n stock is limited only 2-4 unit ready
> 
> thanks all



Yes, your edit is correct.
Here is my date of manufacture code, it's on a sticker on the underneath of the unit:







First Pair:Second Pair:0G20070AJanuary0H20080BFebruary0I20090CMarch0J20100DApril0K20110EMay0L20120FJune0M20130GJuly0HAugust0ISeptember0JOctober0KNovember0LDecember

So my one is 0K 0B A... This means it was from 2011, February, First batch in February.

A recent one might be 0L or 0M? 
The main thing is really just the first 2, to indicate the year. Who cares which month or batch really, unless there is a faulty batch.
So if you're buying new, so long as it's 0L or 0M for the first 2 characters, that should be a recently produced item.
Unless they've changed their coding method?

PS, there are no new features, so to speak. It's just a code for Maha to know which batch a particular unit was produced in, like a date code. When it first came out in the mid 2000's there was initially a bug or two which were ironed out in subsequent models, but that was all done in about 2006/2007, IIRC, and there have been no upgrades or updates that I'm aware of.
"If it ain't broke..."

http://www.candlepowerforums.com/vb...r-Maha-C9000&p=3610722&viewfull=1#post3610722

http://www.candlepowerforums.com/vb...r-Maha-C9000&p=3859358&viewfull=1#post3859358


----------



## NeoLoop

Thank you bro samgab,
for pic n quick respon, so nice share :thumbsup:


----------



## AlphaBetaOmega88

Hi, i am new to the world of re-chargeable batteries. Not sure if this has been answered to before or if anyone has encountered this situation, please enlighten me if anyone has info to share. Thank you. 

1) I am using Powerex 2700mAH AA batteries for my wireless microphones and i am using the Maha MH-C9000 chargers. As advised by the re-tailer, i had done a break-in to all my batteries first before using them. After the batteries had been drained from usage, i recharged the batteries using the CHARGE mode with Charge rate set to 500. When the charging is completed (DONE was displayed), i noticed that the mAH values for the batteries were not anywhere near to 2700mAH. I got various values between 1800mAH to 2250mAH. Does this mean that the batteries are not fully charged? I tried emailing MAHA but they have not replied back.

2) What is the lifespan of these re-chargeable batteries or rather how do i know when i should replace these batteries with new ones? Is there any guidelines? Based on my current usage, i am charging these batteries 3 times a week. 

Thank you for your help.:thumbsup:


----------



## N8N

I am guessing that your devices are shutting off before the cells are fully discharged, therefore you're not getting the full 2700 mAh of use out of them.

run a discharge cycle on some cells, the C9000 will cut off at 0.9V and tell you what the capacity of your cells is, that'll let you know which ones are degrading.


----------



## NeoLoop

When charging AAA cell then power blink (interrupted) for awhile, MHC9000 will reset setting to default 1000 mAh. 
Why MHC9000 do not change charging rate default for AAA to 0.5c (400 mA ~ assume AAA 800 mAh) because default 1000 mAh is more than 1c ? 
MHC9000 manual pdf recommendation, do not charging rate more than 1c, it's contradiction.
I already read NC2500 manual pdf there is 2 default charging rate setting for AA & AAA cell.


----------



## AlphaBetaOmega88

N8N said:


> I am guessing that your devices are shutting off before the cells are fully discharged, therefore you're not getting the full 2700 mAh of use out of them.
> 
> run a discharge cycle on some cells, the C9000 will cut off at 0.9V and tell you what the capacity of your cells is, that'll let you know which ones are degrading.




Thank you


----------



## Newguy2012

What capacity should put in the break in mode current capacity or rated battery capacity? I did a break for 1 eneloop at the end it said 18ma. It had 1500+ from refresh and analyze. Did it just kill the battery? Or is that the difference added?


----------



## donn_

I don't really understand your question, but on BI, you enter the rated capacity of the cell.


----------



## Newguy2012

I had the battery analyzed. Do I use that number or the rated capacity that's print on the battery? What does the end result mean for my battery? It said 18ma. Does that mean the battery is dead?


----------



## donn_

What is it about what I posted that you don't understand? When you run BI, you enter the "RATED" capacity of the cell.

The charger will then proceed to charge the cell at 1/10th the "RATED" capacity for 16 hours.

It makes no difference what your analysis run told you. Run BI at "RATED" capacity.


----------



## Newguy2012

I got it. You lost me on "but on BI(?)". I guess you mean "Put on Battery Indicator".


----------



## donn_

Newguy2012 said:


> I got it. You lost me on "but on BI(?)". I guess you mean "Put on Battery Indicator".



Sorry...BI = Break In.


----------



## SilverFox

Hello Newguy2012,

18 mA us a charge rate. If you entered 180 as the capacity the charger would charge at 18 mA during the break in.

If the reading is 18 mAh then that means that you are missing most of the capacity of the cell,

Try running the break in again (using 1800 as the capacity) on that cell and see if the results can be duplicated.

Tom


----------



## nimanchev

Hello! I have registered here to follow this magnificent, state of the art thread.I have more than strange experience with thee C-9000, so I would like to share some with you and ask a few questions.I currently own the C-9000, with 0L0EA written on the back of it.
My first two C-9000 chargers had died, when trying to charge cells, that had been discharged to the maximum.I first did some disharge, then rest, then discharged again at 100 ma.Fortunately, this is no longer the case, but I am struggling to ressurect some old cells...I have run over 10 break-ins and there was no capacity increase.
I have 4 X AA from LIDL, TRONIC 2500 mAH.They were charged best at 700 ma, anything else resulted in about 2100 mAH final capacity, while charging at 700 ma did reach the advertised 2500 mAH.They were dirt cheap, something like 4 $ for a pack of 4 cells, and I got two packs.It has been only a year and 3 cells showed HIGH.I then mixed them with healthy batteries in the torch, drained them all, and I was able to squeeze about 2 months more usage, before finally tossing them.Now the rest of them reach about 1800 mAH.
I have Varta LSD Ready 2 use, they are advertised as 2100 mAH and now a couple of years old.They also reach about 1800-1900 mAH, and one of them reaches only 1500 mAH.Since break-in does not help with both Varta and Tronic, could you recommend any solution? C-9000 allows up to 12 cycles.Maybe this is what I should do ?


----------



## samgab

nimanchev said:


> ...Since break-in does not help with both Varta and Tronic, could you recommend any solution?...


Especially in the case of the "Tronic" cells, I recommend: Buy better cells. The C9000 does not have some magical ability to make rubbish cells good, no matter how many times you cycle them. Welcome to CPF, BTW 

PS, Varta LSD aren't too bad, I have 2 dozen of them, but they aren't as good in my experience as eneloops, and if they're only giving 1500 mAh and it doesn't get better after 1 break-in, they won't get better no matter what you do, I'm afraid. Relegate them to TV remote duty or similar.


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## nimanchev

Thank you ! I think I will continue intensivly using the Tronic cells, until I see HIGH again ( LOL ), it won`t be long.As for the Varta Ready 2 Use, the 1500 mAH cell is at least 3 years old.I have one Kodak Pre-charged sell, and two more Varta Ready 2 Use that I bought recently.I was thinking of buying two more Varta LSD for 6 €, and toss the older Kodak and Varta, but for the price, I can get 4 x Digibuddy LSD from eBay.BTW, I have 4 x AAA LSD 900 mAH from Digibuddy, they measure from 920 to 964 mAH, and I can recommend them over the Imedions - they are on par, but one of the Imedions died in a few months in a Cateye rear tail light.I have seen claims over CPF that Imedions tend to loose their LSD feature in just one year...


----------



## nimanchev

Hello! I am about to get both standart and XX Eneloops, and GP Recyko+ AA batteries, so I have to ask a few things about both charging and discharging.I know that the C-9000 applies top-off charge, but I always charge either at 0.5C, or less ( whichever brings the best results ), and after the charger is DONE, I immediately re-insert the batteries and charge them at 200 ma - it always manages to put in from 70 to 120 mAH ! So, is there anything wrong with that, how can I improve my chargins " skills " ?
I discharge the batteries at 0.2 to 0.5 C, and at the end, I always re-insert the batteries and discharge at 100 ma.I have always thought that this avoid any memoery effect...But I have read some people recommending NEVER to discharge completely the battery, as is it unlikely to catch up with the voltage drop.


----------



## bluechunks

Is top-off charge applied during the rest period for Cycle mode? There is a post from willchue from 2007 stating that it is not, but I was hoping this was changed in a later firmware version.

The post from willchue is here: http://www.candlepowerforums.com/vb...Thread&p=1766136&highlight=topoff#post1766136


----------



## bluechunks

Also, is the *top-off* charge is applied during the* rest period for Refresh and Analyze mode*? I would expect it to since part of the purpose of Refresh and Analyze mode is to check the batteries capacity, and the battery does not reach full capacity without the topoff charge.

Note, I am specifically asking about the reset cycle. The c9000 user manual implies that topoff is applied for Refresh and Analyze mode, but does not state when it is applied (is it applied only after the final charge, or is it applied both during the rest period and after the final charge). Thank you


----------



## bluechunks

I ran a test with a new set of 4 Eneloop XX AAA batteries showing 3% higher capacity from break-in mode than from refresh/analyze (for same discharge current) Note sure if the difference is caused by break-in's 16 hour 0.1C charge, or could also be indication that topoff is not applied during refresh/analyze rest period. 



Brand new set of 4 Eneloop XX AAA batteries
Ran full break in cycle so batteries achieve peak capacity.
Next ran discharge cycle at 200mA. The recorded capacities during the discharge cycle were 948/939/936/968.
Next ran Refresh/Analise with discharge=200mA and charge=400mA. The recorded capacities for the refresh/analyze cycle were 919/914/911/941


----------



## SilverFox

Hello Bluechunks,

Welcome to CPF.

I don't believe the top off charge is applied during the cycles of Refresh and Analyze. It is applied after a normal charge and it may be applied after the final charge of Refresh and Analyze. It is not done during Break In.

Tom


----------



## fridgemagnet

Help please - I did a break in cycle on some fairly new eneloop 3rd gen. AAA's, and they finished at 955 and 932 mAh. 
Voltage reading Maha m9000 was 1.52V and 1.53V
Voltage reading on my Tenma multimeter 1.486V 1.491V
I had set the charge current to 300mA for both - did they miss delta V, or was this normal????
- or is my Maha faulty?


----------



## Power Me Up

bluechunks said:


> Also, is the *top-off* charge is applied during the* rest period for Refresh and Analyze mode*? I would expect it to since part of the purpose of Refresh and Analyze mode is to check the batteries capacity, and the battery does not reach full capacity without the topoff charge.
> 
> Note, I am specifically asking about the reset cycle. The c9000 user manual implies that topoff is applied for Refresh and Analyze mode, but does not state when it is applied (is it applied only after the final charge, or is it applied both during the rest period and after the final charge). Thank you



As far as I'm aware, the only time that the C9000 doesn't apply a top off charge is for the break in mode. All other modes have a top off after charging - both during cycling and also for the last charge.

I know I'm contradicting SilverFox with this, so I checked with a couple of C9000 chargers that I have - as far as I could tell, the chargers were making the same PWM chirping noise (indicating that the top off was occurring) after terminating a normal charge and after terminating a charge on either the cycle or R&A mode.


----------



## SilverFox

Hello Fridgemagnet,

I think that is a normal ending voltage after (or during) the top off charge.

Tom


----------



## SilverFox

Hello Power Me Up,

Now I am going to have to run some cycles and check this out.

There are 2 issues. One is that I never use the Cycle or Refresh and Analyze functions, and the other is that I am using early versions of the charger (0F and 0G) and Maha may have changed something in later models.

Tom


----------



## Power Me Up

SilverFox said:


> Hello Power Me Up,
> 
> Now I am going to have to run some cycles and check this out.
> 
> There are 2 issues. One is that I never use the Cycle or Refresh and Analyze functions, and the other is that I am using early versions of the charger (0F and 0G) and Maha may have changed something in later models.
> 
> Tom



The testing that I did was on 0G0B01 models so you should be fine to test on those. The 0F model won't be doing a top off charge since it was between these models that they changed the charge termination method and added the top off mode.

It's of course possible that they've changed things again in more recent versions, but I haven't seen any reports of that being the case.


----------



## SilverFox

Hello Power Me Up,

You are correct. At least for the cycle mode. During the rest period the charger applies the top off charge. This can be verified by checking the voltage of the cell as it enters the rest period and then checking it again just before the discharge starts. The cells that I am working with right now showed 1.44 volts at about 10 minutes into the rest period and that voltage rose to 1.46 volts near the end of the rest period.

Tom


----------



## bluechunks

Tom, thanks for the check on rest period for cycle mode. I will check for Refresh/Analyze and report back to the forum (next time I run Refresh/Analyze, I will monitor the voltage during the rest period to see if it increases). BTW I purchased my C9000 about a month ago and the firmware version is 0M0FA.


----------



## bluechunks

I was wondering which mode other folks are using for battery matching: Break-in or Refresh/Analyze. Break-in may report a higher capacity than refresh/analyze on account of the 0.1C 16 hour charge.

One caveat - capacity reported by break-in mode is measured before the battery forming is compete, thus the reported capacity may not be useful for a battery has sat around too long (Break-in does 0.1C charge for 16hrs, 0.2C discharge where capacity is measured followed by another 0.1C charge for 16 hours). An alternative may be to perform a break-in followed by Refresh/Analyze and use the capacity from the Refresh/Analyze pass for battery matching.


----------



## SilverFox

Hello Bluechunks,

Welcome to CPF.

When matching cells the best results come from testing them similar to how they will be used.

For example let's say I have some cells that I want to use. I will charge them up and then set them aside until the next day. I will then measure the resting voltage to see if rapid self discharge is a problem. I will then discharge them at a rate that is close to what they will see in service. During the discharge I will note the voltage under load and then will match on capacity and voltage under load.

I use the break in as a check of the cells general health. When the cell drops below 80% of its initial capacity I recycle it. If the cell passes this test I move on to see how it performs under the actual use conditions that I intend to use it in.

Tom


----------



## bluechunks

Battery conditioning recommendations for folks that use the c9000 with Low Self Discharge batteries: I emailed Maha tech support regarding this and their response was:

Run a refresh after every tenth charges, and to run the break in once every six months

Here is the full context of the question to Maha Tech support:
---------------------------------------
Sent: Saturday, March 22, 2014 5:57 PM
To: [email protected]

I have a question regarding the MH-C900 charger when used with Imedions. The manual makes the following recommendation:

- For “batteries in storage for more than 2 weeks but less than 3 months”, use “Refresh & Analyze”
- For “batteries in storage for more than 3 months, use “Break-in”

I am assuming these recommendations would not apply for “low self-discharge” batteries such as the Imedions, since they would still be almost fully charged at 3 months.

What are the recommendations for Imedions (when should you use Refresh & Analyze and when should you use break-in)? Thank you
---------------------------------------
Eric Cheng - Maha Energy [email protected]
Mar 24
Thank you for contacting Maha. Yes, you are absolutely correct. The recommendations for the Imedion is to run a refresh after every tenth charges, and to run the break in once every six months.

Regards, Eric Cheng


----------



## tony1tf

Hi 
Just found this forum. 
I have owned one of these battery analysers for a long time now and am very pleased with it. I have one question and a trick I use, which may have been posted previously:
Is there any way to get a logger output from the MH-C9000? - I would love to be able to record cells characteristics on a PC or microcomputer like a Raspberry Pi. I wondered if it has an undocumented serial output or similar somewhere. 
Secondly - I do a lot of cell recycling from scrap battery bins at supermarkets, so I often have problem cells. Particularly AAA batteries which have too high an internal impedance, and give the "HIGH" error. I usually manage to get the charger to work with these cells by putting a 1.5 ohm resistor attached to thin brass plates in parallel with the cell until the voltage settles to 1.3 volts or so. Then removing the resistor allows the analyser to carry on. Sometimes the cell will still misbehave on discharge, showing a very low (but unreal) capacity. Are others doing this sort of thing? 
I suppose I ought to do a comprehensive search on this thread.
Tony


----------



## SilverFox

Hello Tony,

Welcome to CPF.

I don't believe there is an output, hidden or otherwise.

As far as "tricking" the charger goes, many people prefer not to use cells with high internal resistance. They appreciate the fact that the charger rejects these cells. The main issue with charging high internal resistance cells is heat. Be sure to choose a charging rate low enough to minimize excess heat. The charger is set up to reject charging primary cells. If you bypass this and the cell heats up enough to melt the charger, don't expect sympathy from MAHA...  

Tom


----------



## IonicBond

tony1tf said:


> ... Then removing the resistor allows the analyser to carry on. Sometimes the cell will still misbehave on discharge, showing a very low (but unreal) capacity. Are others doing this sort of thing? ..



Those that are may be fooling themselves into thinking that keeping high-resistance batteries alive for low-current devices is somehow saving the environment. The problem is that these batteries are more resistor than battery when under about 80% original capacity, and it actually takes longer to charge, and due to high self-discharge need to charge them more often.

What this means is that you are actually wasting more resources on them than if you just recycled them and started with new ones. I suppose your "carbon footprint" on the environment is greater on junk cells, but this is not immediately apparent to those who don't actually measure the power wasted at the outlet trying to keep those zombie-batteries alive.


----------



## WalkIntoTheLight

IonicBond said:


> Those that are may be fooling themselves into thinking that keeping high-resistance batteries alive for low-current devices is somehow saving the environment. The problem is that these batteries are more resistor than battery when under about 80% original capacity, and it actually takes longer to charge, and due to high self-discharge need to charge them more often.
> 
> What this means is that you are actually wasting more resources on them than if you just recycled them and started with new ones. I suppose your "carbon footprint" on the environment is greater on junk cells, but this is not immediately apparent to those who don't actually measure the power wasted at the outlet trying to keep those zombie-batteries alive.



I'm not interested in "saving the environment" by hanging on to old cells. I'm interested in saving the cells! They may have high internal resistance, but that matters very little if the current is low in the device you're using them, and if you charge them slowly they're fine too. I have 14 year old cells that I still use in low drain devices. I charge them slowly (250-300 mA), and they're still fine cells for some uses.

I don't have a C-9000, but if I get one, I'll make sure to keep an old charger that can handle cells with high internal resistance.

Who said anything about carbon footprints???


----------



## Power Me Up

tony1tf said:


> Hi
> Just found this forum.
> I have owned one of these battery analysers for a long time now and am very pleased with it. I have one question and a trick I use, which may have been posted previously:
> Is there any way to get a logger output from the MH-C9000? - I would love to be able to record cells characteristics on a PC or microcomputer like a Raspberry Pi. I wondered if it has an undocumented serial output or similar somewhere.



Like SilverFox, as far as I'm aware, there's no logging output that you can get on the C9000 even if you were to disassemble it.

I don't know if anyone has done it with the C9000, but I recall reading about someone who used a web cam to capture an image of an LCD screen, convert the image to a value with OCR and then log values that way. Might have been with a regular multimeter - it'd be a bit more difficult with the C9000 since it cycles through different readings as well as each of the slots.

The next option is to get a hobby charger that has a PC connection - there's quite a few different models around. As a general rule though, most are only good for testing one cell at a time - you might be able to test a battery pack using the balancing wires, but that's only going to work reasonably well if all the cells are fairly evenly matched.

An even better option (In my opinion - maybe a little biased though since I've written the firmware for it) is the UltraSmartCharger - it can log data to an SD card as well as output it via a TTL serial connection on the non LCD version. The LCD version which is in the process of being finalised can log via I2C - either option should be suitable if you want to read the data on a Raspberry Pi as it's happening.



> Secondly - I do a lot of cell recycling from scrap battery bins at supermarkets, so I often have problem cells. Particularly AAA batteries which have too high an internal impedance, and give the "HIGH" error. I usually manage to get the charger to work with these cells by putting a 1.5 ohm resistor attached to thin brass plates in parallel with the cell until the voltage settles to 1.3 volts or so. Then removing the resistor allows the analyser to carry on. Sometimes the cell will still misbehave on discharge, showing a very low (but unreal) capacity. Are others doing this sort of thing?
> I suppose I ought to do a comprehensive search on this thread.
> Tony



I'd never thought of using a resistor to fool the C9000 with high resistance cells. Most people don't bother with high resistance cells on the C9000 and just charge them on something else.

My own opinion on high resistance cells is different to SilverFox - in my opinion, I'd rather use high resistance cells in low drain devices rather than discard them and use alkalines. It's a bit of a waste using good rechargeables in low drain devices, but as long as high resistance cells haven't developed high self discharge and their capacity is still reasonable, giving them some use in low drain devices extends their usable life.

The UltraSmartCharger will also reject high resistance cells at a similar level to the C9000 (in an effort to try to prevent accidental charging of non rechargeables such as alkalines, etc), but the key difference with the UltraSmartCharger is that all you have to do is to start the charge again and the charger will happily continue on and charge them. If the internal resistance has gone up significantly, the charging current will be automatically reduced to compensate. Often, the internal resistance will drop as the cell is charged and it warms up, in which case, the UltraSmartCharger will automatically increase the charging current as this happens.

Since you've mentioned AAA cells, I'll also mention that the current versions of the UltraSmartCharger are intended primarily for AA cells. I get around that though by using a couple of gold plated rare earth magnets in each slot to reduce the length of the slots to suit AAA cells.


----------



## tony1tf

Power Me Up said:


> Like SilverFox, as far as I'm aware, there's no logging output that you can get on the C9000 even if you were to disassemble it.
> 
> I don't know if anyone has done it with the C9000, but I recall reading about someone who used a web cam to capture an image of an LCD screen, convert the image to a value with OCR and then log values that way. Might have been with a regular multimeter - it'd be a bit more difficult with the C9000 since it cycles through different readings as well as each of the slots.



In the absence of a serial output, I was thinking about decoding the LCD signals directly - requires a lot of reverse engineering. If anyone from Maha monitors this thread, perhaps they can get in touch and save me the trouble ;-)




> An even better option (In my opinion - maybe a little biased though since I've written the firmware for it) is the UltraSmartCharger - it can log data to an SD card as well as output it via a TTL serial connection on the non LCD version. The LCD version which is in the process of being finalised can log via I2C - either option should be suitable if you want to read the data on a Raspberry Pi as it's happening.



That and your blog looks great - I hadnt seen your kickstarter project before. I have done lots of logging of cell discharge over the years, using a LabJack data logger. Gets a bit compulsive, doesn't it. If you want any beta testing doing with my stash of good and grotty cells, let me know.

regards
Tony


----------



## Power Me Up

tony1tf said:


> In the absence of a serial output, I was thinking about decoding the LCD signals directly - requires a lot of reverse engineering. If anyone from Maha monitors this thread, perhaps they can get in touch and save me the trouble ;-)



That's an interesting idea. I suspect that the LCD signals are multiplexed which can make that a bit more difficult to do. Would be interesting to hear how you go with it though!




> That and your blog looks great - I hadnt seen your kickstarter project before. I have done lots of logging of cell discharge over the years, using a LabJack data logger. Gets a bit compulsive, doesn't it. If you want any beta testing doing with my stash of good and grotty cells, let me know.



You're actually thinking of Paul who created the charger - I'm Mark and I've only written the firmware for the charger so I can't take any of the credit for the blog or the KickStarter project!

I don't know if Paul is looking for beta testers this time around, but I don't see any harm in contacting him to see if he's interested. Just keep in mind that he's pretty busy between work/family life plus trying to assemble a heap of chargers, so it may take him a while to get back to you.


----------



## Mr Floppy

Power Me Up said:


> I don't know if anyone has done it with the C9000, but I recall reading about someone who used a web cam to capture an image of an LCD screen, convert the image to a value with OCR and then log values that way. Might have been with a regular multimeter - it'd be a bit more difficult with the C9000 since it cycles through different readings as well as each of the slots.



I've mentioned it. It was based off a post on this forum where someoneuse OCR and logged a regular multimeter. 

I've tried it myself on a Raspberry Pi, used SSOCR to read the seven segment display. The problem is that it does cycle through different batteries so only one battery at a time, or work out the timing of the cycles. You have blockout all the other bits of display as it affects the way SSOCR interprets the segments. Probably doable given more time but with other analysers out there, it isn't necessary.


----------



## tony1tf

Mr Floppy said:


> I've mentioned it. It was based off a post on this forum where someoneuse OCR and logged a regular multimeter.
> 
> I've tried it myself on a Raspberry Pi, used SSOCR to read the seven segment display. The problem is that it does cycle through different batteries so only one battery at a time, or work out the timing of the cycles. You have blockout all the other bits of display as it affects the way SSOCR interprets the segments. Probably doable given more time but with other analysers out there, it isn't necessary.



Hi Mr Floppy

That SSOCR code looks really interesting. Are there any particular libraries that have to be downloaded for the Pi? Presumably you just recompiled it for the ARM processor in the Pi? I would love to use it and add bits that recognise the various pointers on the screen of the C9000, so that the 4 cells can be read independently, along with what each number means. I would put the C9000 in a box at a fixed location with the Pi camera. It would be a simple and quite cheap mod for C9000 owners.

Tony


----------



## Mr Floppy

tony1tf said:


> Are there any particular libraries that have to be downloaded for the Pi? Presumably you just recompiled it for the ARM processor in the Pi?



Yes, you also need the X11 and imlib headers to compile it. 

sudo apt-get install libx11-dev
sudo apt-get install libimlib2-dev

It is quite good, and no you don't need a Raspberry Pi (or Pi camera) but it is a good way to get this going. I was trying to use Tesseract-ocr before but I think SSOCR is much better for seven segment displays. Tesseract may be better for reading the other bits of the screen perhaps. Another tip, if you don't use a piece of black paper to block out the rest of the display, you can always use Imagemagick to crop the picture down to size, plus a heap of other filters you can apply to the picture. 

I would love to see what you can do with it. I wanted to do more with it myself but will get back to it one day ...


----------



## shelm

For my records, i got 6 new NiMH batteries AAA size 750mAh nominal, "standard charge 16h/75mA (0.1C), fast charge 4.5h/225mA (0.3C)", production code "15 14" Made In China, and thought i'd reset them to factory condition EITHER by Break_In mode (enter 800mAh) OR by Cycle mode (enter 400/-300mA). Interestingly, a single run of the Break_In mode on cells#1-4 resulted in ~650mAh only. Subsequent Cycle (N=6) did bring the reading up to ~770mAh. For cells#5-6 i decided to skip the Break_In mode and do Cycle (N=5) from the very start, here my results:

cell#5cell#61st CYCLE736 mAh693 mAh2nd CYCLE774 mAh749 mAh3rd CYCLE786 mAh768 mAh4th CYCLE790 mAh773 mAh5th CYCLE789 mAh771 mAh

I am learning that the slow charge/discharge of Break_In is less effective than Cycle (~650mAh vs 736/693mAh) to get the battery back in shape, and that it takes N=4 cycles to reach the plateau. Doing a Break_In *after* the CYCLE mode will reproduce the last results (789/771).

Why for my records? Well, the batteries are new and made in China and MH-C9000 gives us the luxury to make serious measurements. We can see the effect of cycling of (new) cells which didn't get any use since they had left the factory a few months back. I am learning that the label "750" is no bull but really the capacity of the cells, even at fast charge/fast discharge, not only standard charge/standard discharge conditions.

I am not saying that new purchased Eneloop batteries, produced 1 year ago, exhibit the same type of behavior. They probably don't need any cycling (enter 400/-200mA) to get back to factory condition.

Point is, you buy new China-made cells and do not own a CYCLER like BC700 or MH-C9000, then you may operate your cells at the 650mAh level instead of the reset 789mAh level :huh:

Thanks for your attention. After all the Break_In's and Cycle's, i didn't want to let all numbers go to waste, so i decided to record 1 set here.


----------



## SilverFox

Hello Shelm,

If it is not too much trouble...

Take a couple of your cells that you have data on and having completed the cycling discharge them and run them through a Break In cycle again. You may find some differences in your numbers.

If I remember correctly there is a difference in the rest periods used. Cycle mode doesn't utilize a rest period between charging and discharging. This gives you "optimum" capacities because the discharge includes the surface charge and the cells are warm. The Break In includes a rest period for the surface charge to bleed off and allows the cells time to cool off after charging.

Measuring the capacity "hot off the charger" inflates the capacity. Unless you use your cells "hot off the charger" in something like RC racing the added capacity can not be realized.

At any rate, it would be interesting to see what you come up with.

Tom


----------



## shelm

SilverFox said:


> Hello Shelm,
> 
> If it is not too much trouble...
> 
> Take a couple of your cells that you have data on and having completed the cycling discharge them and run them through a Break In cycle again. You may find some differences in your numbers.
> 
> If I remember correctly there is a difference in the rest periods used. Cycle mode doesn't utilize a rest period between charging and discharging. This gives you "optimum" capacities because the discharge includes the surface charge and the cells are warm. The Break In includes a rest period for the surface charge to bleed off and allows the cells time to cool off after charging.
> 
> Measuring the capacity "hot off the charger" inflates the capacity. Unless you use your cells "hot off the charger" in something like RC racing the added capacity can not be realized.
> 
> At any rate, it would be interesting to see what you come up with.
> 
> Tom



Hi Tom,

i just completed a BREAK_IN on cell#5 and cell#6. Interestingly they ended up 807mAh and 797mAh respectively.
Yes you're right with the rest periods, they differ. This kind of info should be in the Maha FAQ-thread, sticky. I have observed the following rest times:



REFRESH&ANALYZE: *C* > 2.0h rest > *D *> 1.0h rest > *C*
BREAK_IN: *C *> 1.0h rest > *D *> 1.0h rest > *C*
CYCLE: *C *> 2.0h rest > *D *> 1.0h rest > *C *> 2.0h rest > D > 1.0h rest > C > etc.
 
Am wondering why Maha employs different rest times for the programs. Please feel free to confirm my observed rest times, thanks!


----------



## HKJ

shelm said:


> Hi Tom,
> 
> i just completed a BREAK_IN on cell#5 and cell#6. Interestingly they ended up 807mAh and 797mAh respectively.
> Yes you're right with the rest periods, they differ. This kind of info should be in the Maha FAQ-thread, sticky. I have observed the following rest times:
> 
> 
> 
> REFRESH&ANALYZE: *C* > 2.0h rest > *D *> 1.0h rest > *C*
> BREAK_IN: *C *> 1.0h rest > *D *> 1.0h rest > *C*
> CYCLE: *C *> 2.0h rest > *D *> 1.0h rest > *C *> 2.0h rest > D > 1.0h rest > C > etc.
> 
> Am wondering why Maha employs different rest times for the programs. Please feel free to confirm my observed rest times, thanks!



As can be seen from my review, the 2 hour rest is not really a rest, but part of the charging.


----------



## SilverFox

Hello Shelm,

As HKJ pointed out the Maha charger uses a 2 hour top off charge after the main charge. With both Refresh and Cycle there is no rest period and the discharge starts right after the top off charge finishes.

The Break In function is a timed function so there is no top off charge included. The closest approximation to the labeled capacity comes from using the Break In function.

Some NiMh cells benefit from cycling as you have observed. If I have cells that have been in storage for awhile or with new cells that aren't low self discharge chemistry I will usually run them through several charge/discharge cycles to "break them in" before running a Break In cycle to see where they stand.

Many people feel that the standard Break In takes too long so they only do charge/discharge cycles and go with the discharge capacity they get under slightly higher discharge rates. In actual practice the results can end up very similar so it is hard to argue against doing that.

The battery industry uses a standard to define the capacity of the cells they produce. The Maha Break In function comes close to following that standard. Sometimes the labeled capacity is based upon theoretical maximum values and the actual capacities will be a little less. Sometimes a cell needs some exercising before it becomes "vibrant" for use. Other times it works well right from the start. In your case it looks like they needed some exercise to get back into shape.

Tom


----------



## Wolf Lonesome

SilverFox said:


> Hello Handlobraesing,
> 
> You have made an important discovery... Crap cells don't perform well. :devil:
> 
> I have found that it is far less frustrating to recycle crap cells and replace them with new cells that are performing well. However, there can be some educational opportunities from playing with crap cells.
> 
> If you want to play, try this...
> 
> Charge your cells at 1000 mA. When Done is displayed, set a timer for 3 hours. When the timer goes off, start a 500 mA discharge.
> 
> Record the capacity you get and compare it to the labeled capacity of the cell.
> 
> Leave the cells in the C9000 and set a timer for 30 minutes. Then do another discharge at 200 mA.
> 
> When that discharge is completed, once again, set the timer for 30 minutes, then do another discharge, this time at 100 mA.
> 
> Next, do a Break-In cycle. Once again, record the capacity and compare it to the labeled capacity.
> 
> Set a timer for 1 hour, then discharge at 500 mA.
> 
> Record the capacity and compare it with what you got during the first 500 mA discharge. If you see an improvement in capacity, the cell is starting to recover and you can repeat this process again.
> 
> After 10 rounds of this, if your crap cells are going to recover, they should be at or above about 80% of their labeled capacity.
> 
> On the other hand, if your crap cells are still crap, recycle them and move on. If you have a secial "attachment" to them, find a crap application for them and don't be frustrated when they crap out on you.
> 
> Have you tried running any healthy cells through charge/discharge cycles on the C9000? How did they do?
> 
> Tom



Hello Tom!

Should I use your method to improve the capacity of some of my Eneloop AA cells?
I remember also another way to revive crap cells.

12 cycles of Refresh/Analyze @500 mA charge/100 mA discharge.

Thanks for your expertise,

Peter


----------



## kreisl

Wolf Lonesome said:


> 12 cycles of Refresh/Analyze @500 mA charge/100 mA discharge.



Hopefully Tom agrees with me. 500mA/-100mA is too tame to get a sleeping Enelup back to top condition. You need to train with heavy weights to get bigger muscles. (analogy)


----------



## SilverFox

Hello Peter,

I have very limited experience with damaged Eneloop cells. The ones that I have tried various things with have not responded.

Degradation usually results from either using up the materials inside the cell or an unequal distribution of the the chemicals inside the cell. When the materials get used up there is nothing you can do. If the chemicals become unevenly distributed there are two schools of thought on this. One involves slow charging and repeated discharges. The other involves higher rate charge/discharge cycling. Both work. The common theme between them is subjecting the cell to charge/discharge cycles.

My perspective is that a cell with reduced capacity due to an imbalance of chemicals in it would respond more favorably and have a smaller risk of damage if you use lower currents over a longer period of time. I have friends that prefer higher current cycling. We both are able to recover cells but I think I have a slightly higher percentage of recoveries so I have a bias toward lower current efforts.

The low self discharge cells have a little different chemistry so as they begin to wear out it will be interesting to try to figure out what helps and what doesn't.

If you are trying to recover some Eneloop cells, consider yourself a pioneer.

Tom


----------



## Wolf Lonesome

Hi Tom!

Thanks for the explanation.
Do you have any suggestion how to use BC-700 or Schulze to regain the lost Eneloop capacity?
You have mentioned somewhere about your success in recovering a few cells using the Schulze charger.
Can you reveal your "secret" .

Cheers,

Peter


----------



## SilverFox

Hello Peter,

If I were trying to rejuvenate a cell that was under performing I would start with a "complete" discharge followed by a charge like the Break In mode used by Maha. And then realize that it may take a few cycles of this to make a difference. Keeping track of discharge capacities and voltage under discharge loads will tell me if I am making progress or not.

I have already identified a method to discharge a cell. I may even short it out overnight to get a more complete discharge. 

Schulze offers an automatic charge that varies the charge rate depending upon the cells internal resistance. It addition it has a long duration formatting charge setting. This combination seems to help if the damage to the internals of the cell are minimal.

The sequence starts with a "normal" charge followed by measuring the capacity during a "normal" discharge. This is your benchmark and the goal is to get a higher number as a result of your efforts. Next additional discharges are done in an effort to completely empty the cell. Next comes the auto charge and this is followed by 24 hours of formatting charge. Let the cell rest an hour or so then do another "normal" discharge. Compare the results and repeat.

The exciting ones come back after a cycle or two. The others show very little change after a week of effort and you begin to wonder if it may be better to retire the cell and move on...

Tom


----------



## Wolf Lonesome

Hello Tom,

Let say I will first discharge the cells at 100 mA using BC-700 and the run a break in using the C9000.
Then I will end the 16 hour charge and use the BC-700 again for discharge and record a capacity.
Maybe I should I use a diode and resistor to further discharge down to 0.8 V.
I believe, this makes sense...

Can you give me any detailed instructions how to effectively try to recover these 2010 Eneloops?

Peter


----------



## SilverFox

Hello Peter,

I have very limited experience trying to recover Eneloop cells. I was not successful with anything that I tried. You are on your own here...

Tom


----------



## Bright+

I have one from when it was released. Many of us here know that battery performance depends a lot on current. The way it works is causing a lot of problems. Does the newest version have a real algorithm that uses much faster or actual current regulation to actually reflect impact on battery the same as true current level shown in display? 

It is just cycling a resistor that corresponds to approximately 1A with a switch and it does it quite slow at once every other second. The voltage is flash reading the voltage under 1A of load regardless of battery size and reading a voltage under load at 1A regardless of it is 600mA AAA and 2500mA AA is unreasonable. It will immediately jump to "done" on slightly tired cells, because voltage drop at 1A is quite a bit. 

When you set it to 100mA discharge rate, it draws full load for 0.2 seconds and take a voltage under load, rest for 1.8 seconds and assumes it is the same as drawing 0.1A into a continuous load. Cells terminate prematurely at end of cycle with plenty of cycles left if the load under 1A falls below 0.9v regardless of settings. 

On charging, a 2,000mAh battery do not see any productive gain from a 10mA trickle charge, but it will accept charge at 600mA for a second every minute. When you're doing cycle tests, I don't think 1,000mAh battery sees 2A for 0.1 seconds every two seconds for 16 hours the same as a steady 0.2A for 16 hours and I think it causes over charging. I think the rate is slow enough that it acts more like a blinker than actual dimming.


----------



## kreisl

Bright+ said:


> I have one from when it was released. Many of us here know that battery performance depends a lot on current. The way it works is causing a lot of problems. Does the newest version have a real algorithm that uses much faster or actual current regulation to actually reflect impact on battery the same as true current level shown in display?
> 
> It is just cycling a resistor that corresponds to approximately 1A with a switch and it does it quite slow at once every other second. The voltage is flash reading the voltage under 1A of load regardless of battery size and reading a voltage under load at 1A regardless of it is 600mA AAA and 2500mA AA is unreasonable. It will immediately jump to "done" on *slightly tired* cells, because voltage drop at 1A is quite a bit.
> 
> When you set it to 100mA discharge rate, it draws full load for 0.2 seconds and take a voltage under load, rest for 1.8 seconds and assumes it is the same as drawing 0.1A into a continuous load. Cells terminate prematurely at end of cycle with plenty of cycles left if the load under 1A falls below 0.9v regardless of settings.
> 
> On charging, a 2,000mAh battery do not see any productive gain from a 10mA trickle charge, but it will accept charge at 600mA for a second every minute. When you're doing cycle tests, I don't think 1,000mAh battery sees 2A for 0.1 seconds every two seconds for 16 hours the same as a steady 0.2A for 16 hours and I think it causes over charging. I think the rate is slow enough that it acts more like a blinker than actual dimming.



you're mentioning a very good point relevant in practice/theory. in summary, with poor NiMH's (or new Alkaleaks) the CHARGE and the DISCHARGE programs terminate way too early. this is noticeable especially with higher 'transfer rates' but also with the lowest transfer rate possible: 100mA DISCHARGE rate. (apart from that, the C9000 does not accept cells with HIGH resistance and that happens even to some of my Eneloops!) the reason for this §$%&! behavior is the PWM pulsation of the current, which is still there in 2014 production units.

well that's the way the machine works.

oh. 

well.


----------



## Bright+

kreisl said:


> the reason for this §$%&! behavior is the PWM pulsation of the current, which is still there in 2014 production units.
> 
> well that's the way the machine works.
> 
> oh.
> 
> well.



You would think they can tweak the timing of voltage measurement or PWM cycle duration with new firmware.


----------



## StandardBattery

Bright+ said:


> You would think they can tweak the timing of voltage measurement or PWM cycle duration with new firmware.


They could maybe, but discharge and capacity testing should just not be done with pulsed current as its not only inaccurate it does not simulate correctly the typical load characteristics.


----------



## roadwarrior

Hi guys,

I have the Maha Powerex Wizard One MH C9000 loaded in the barrel and all that is left is the trigger pull. With that said, I have read through all the threads/post I could find on here, as far back as 2007. I feel I know all there is to know about this charger, but I thought I would get some final thoughts/opinions from current owners/users on here. A lot of the stuff is a bit dated on here since this charger's debute back in 2007 or so. 

I went as so far to email Maha and ask if there has been any updates recently on this model and they stated no. So in a last ditch effort to cross my Ts and dot my Is, I have come here to get some final feedback.

Thanks in advance guys!


----------



## AlphaZen

roadwarrior said:


> Hi guys,
> 
> I have the Maha Powerex Wizard One MH C9000 in the loaded in the barrel and all that is left is the trigger pull. With said, I have read through all the threads/post I could find on here, as far back as 2007. I feel I know all there is to know about this charger, but I thought I would get some final thoughts/opinions from current owners/users on here. A lot of the stuff is a bit dated on here since this charger's debute back in 2007 or so.
> 
> I went as so far to email Maha and ask if there has been any updates recently on this model and they stated no. So in a last ditch effort to cross my Ts and dot my Is, I have come here to get some final feedback.
> 
> Thanks in advance guys!


As the saying goes, "If it aint broke, don't fix it." The C9000 is perfect for charging/maintaining/analyzing. Pull the trigga man.


----------



## kreisl

roadwarrior said:


> Hi guys,
> 
> I have the Maha Powerex Wizard One MH C9000 in the loaded in the barrel and all that is left is the trigger pull. With said, I have read through all the threads/post I could find on here, as far back as 2007. I feel I know all there is to know about this charger, but I thought I would get some final thoughts/opinions from current owners/users on here. A lot of the stuff is a bit dated on here since this charger's debute back in 2007 or so.
> 
> I went as so far to email Maha and ask if there has been any updates recently on this model and they stated no. So in a last ditch effort to cross my Ts and dot my Is, I have come here to get some final feedback.
> 
> Thanks in advance guys!




http://www.amazon.com/review/RZCMBYAN3QKN3/


----------



## recDNA

I never knew there was a problem charging AAA batteries with this charger. "You will have to push a button 7 times....". Thanks for the Amazon review.


----------



## Dr. Strangelove

I've been using the C9000 to charge AAAs for four years. Pushing the button 7 times is no big deal. Pull the trigger.


----------



## teacher

recDNA said:


> I never knew there was a problem charging AAA batteries with this charger. "You will have to push a button 7 times....". Thanks for the Amazon review.


To be clear, there _*is not*_ a "problem" charging AAA batteries on the *MH C9000*. 
I have charged plenty of them on one. Pushing the button to achieve the desired charge rate can hardly be considered a "problem" as far as I am concerned... however YMMV if you consider it an ""inconvenience"". :thumbsup:


----------



## teacher

AlphaZen said:


> As the saying goes, "If it aint broke, don't fix it." The C9000 is perfect for charging/maintaining/analyzing. Pull the trigga man.


Better advice you will not be given '*roadwarrior*'! :thumbsup: 

Get one.............


----------



## roadwarrior

Thanks for the feedback guys! 

After much homework, the Maha Powerex Wizard One MH C9000 is what I am going with. I have feeling I will not be disappointed.


----------



## teacher

roadwarrior said:


> Thanks for the feedback guys!
> 
> After much homework, the Maha Powerex Wizard One MH C9000 is what I am going with.


Good for you!!! :thumbsup: :goodjob:



roadwarrior said:


> I have feeling I will not be disappointed.


You won't....


----------



## roadwarrior

Pulled the trigger today on the Maha Powerex Wizard One MH C9000!

Looking forward to asking many more questions once I get it and realize I have no idea what I am doing.....

Thanks for all the feedback, I could not have made such an informed decision if it were not for the many folks on here who shared with me their time and knowledge . :thanks:


----------



## roadwarrior

So, I ran a refresh/analyze on a set of 2300mAh Energizers that have been in constant use for 2 months, but recharged with a dumb charger up until now. 

These are the mAh numbers I got at the end:

Slot 1-2222mAh
Slot 2-2159mAh
Slot 3-2212mAh
Slot 4-2172mAh

Thoughts?

Is that good or bad? Do I need to do something else to get up to their rated capacity? Or is that the best I can expect?


----------



## MidnightDistortions

Try a break-in though you may need to cycle them first to get rid of any overcharge. Those capacities are not bad either way.


----------



## roadwarrior

Cycle as in.....run a discharge first....then run a break in....correct?


----------



## MidnightDistortions

roadwarrior said:


> Cycle as in.....run a discharge first....then run a break in....correct?




There's a cycle function that will charge, discharge as many times as you want. I would do the cycle 3x and then if needed run a discharge before doing the break-in.


----------



## roadwarrior

MidnightDistortions said:


> There's a cycle function that will charge, discharge as many times as you want. I would do the cycle 3x and then if needed run a discharge before doing the break-in.



I try that. Thanks!


----------



## BATTY

So after reading this entire thread, there is no top off charge after the break in mode. 

What modes do top off and what would be the best way to top off batteries that have just finished the BI mode?

Seems like a bit of an oversight to omit this on the BI mode, unless it would skew the final capacity numbers?


----------



## Rosoku Chikara

BATTY said:


> So after reading this entire thread, there is no top off charge after the break in mode.
> 
> What modes do top off and what would be the best way to top off batteries that have just finished the BI mode?
> 
> Seems like a bit of an oversight to omit this on the BI mode, unless it would skew the final capacity numbers?



I believe you can assume that your cells are completely "topped off" after the Break-In mode. As I recall, it charges at 0.1 C (or 10% of cell capacity) for *16* hours. I believe in most situations, your cell would be fully charged under these conditions in about 10 hours (!0% x 10 = 100%). So, I am fairly certainly that after 16 hours, the cells will be up to their maximum capacity.

In any case, I usually want to know the cell capacity as accurately as possible, after running an Break-In. So, I usually run a Discharge, and then a Refresh & Analyze after every Break-in. But, if you have know interest in knowing the accurate cell capacity, I am pretty certain you can use cells that have just been "Broken In" without any fear that they might not be fully charged. (PS: In my experience, the capacity shown after a Break-In, or any other mode -- except Analyze" -- for that matter, is not very accurate; they are only approximate.)


----------



## Yamabushi

Rosoku Chikara said:


> As I recall, it charges at 0.1 C (or 10% of cell capacity) for *16* hours. I believe in most situations, your cell would be fully charged under these conditions in about 10 hours (!0% x 10 = 100%).


Although charge efficiency of NiMH varies with the state of charge, the overall efficiency is approx. 66% at 0.1C so you need approx. 15 hours.


----------



## Rosoku Chikara

Yamabushi said:


> Although charge efficiency of NiMH varies with the state of charge, the overall efficiency is approx. 66% at 0.1C so you need approx. 15 hours.



Thanks for explaining this! I finally understand why it charges for 16 hours. (This may be explained somewhere else in this thread, or on this forum... I cant say that I recall ever reading it before. If I ever did it was a long time ago.)

In any case, what you say makes great sense to me now. So, 16 hours should deliver 100% charge, plus a little extra for good measure. Right?


----------



## ComputerTime

Hi,

I did not manage to read through the whole thread; too many posts. 

Anyway, I have been using this Maha charger since it is launched, did not explore much into this C9000 charger.

I just realised that that I have some Imedions and 1 Eneloop (Sanyo) battery is only around one-third of the capacity. I always do a "refresh/analyse" when charging the batteries. These batteries capacity are reduced because I seldom charge them. 

Is it possible to restore the capacity by doing some cycling? How many cycles are required? For charging, the rate that I will use is 700mAH and 300mAh for discharging, since they are all slow discharging battery.

In addition, I have some Imedions that the charger reflects as "HIGH". Is there anyway to revive the battery, or I will have to make way for new battery?

Regards.


----------



## SilverFox

Hello ComputerTime,

Welcome to CPF.

Cycling through charge/discharge can sometimes help revive a cell, but at other times it doesn't do anything at all. You take your chances and live with your results.

HIGH cells mean that the internal resistance of the cell is high. High resistance means that the cell will heat up during charging, especially at higher current charging. To avoid high cell temperature the charger flags high internal resistance as HIGH and refuses to charge them.

High internal resistance also means that the cell will drop in voltage under load and it's performance will be sub par. I recommend recycling the cells and starting with new cells, but others try to find low current draw applications and also find a stupid charger that doesn't check for the resistance of the cells prior to charging and also doesn't have the capability of charging at higher rates.

If you "love" your particular cells and have an attraction to them you can try a deep discharge followed by a Break-In function. Discharge the cells in the C-9000 at 100mA, then put the cell into a single cell light that has a low current draw. Turn the light on and let it run until it shuts off. Then put the cell in for a Break-In. After the Break-In do a discharge and see if the capacity is within 80% of the cells initial capacity. If it is, charge it back up and use it. If it is not, recycle it and move on knowing that you tried.

Tom


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## ComputerTime

Thanks Tom. 

I tried once to use the stupid charger to charge for 2 hours on my "High" Imedion, after that, go through the "Refresh/Analyse" option. It only restored around 10% of the capacity. With the "high" battery, you will not be able to charge/discharge the battery. The C9000 do not allow you to proceed further. 

I guess time for me to get new eneloop batteries. :twothumbs


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## ChrisGarrett

ComputerTime said:


> Thanks Tom.
> 
> I tried once to use the stupid charger to charge for 2 hours on my "High" Imedion, after that, go through the "Refresh/Analyse" option. It only restored around 10% of the capacity. With the "high" battery, you will not be able to charge/discharge the battery. The C9000 do not allow you to proceed further.
> 
> I guess time for me to get new eneloop batteries. :twothumbs



I've been able to trick my Maha C9000 into charging some Sanyo 2700 HSDs that are reading HIGH...like 2.6x volts high.

You just have to insert them, hit the 1A (or 2A) charge rate and start, HIGH will show, remove battery, reinsert battery, rinse and repeat, until the resistance drops to about 2.11v, where my C9000 will begin charging. It was taking me 5-6 times to get them to charge, before I finally ditched them and sent them to the recycling bag.

But a HIGH battery can sometimes be tricked into charging again. That or just use a dumb charger. Eventually, they'll have little left.

Chris


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## MidnightDistortions

Some of my high resistance cells gets charged in the Last Crosse charger, really old ones gets charged in the dumb chargers. I notice most older cells will work in this LED string lights. But I won't bother with cells that will discharge within a day or less. Thats generally when you know all the cycles in the cell has been exhausted.


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## kreisl

Did NE1 say something about broken pins, cracked posts, broken screw posts or alike? Oh no, that was in the other charger thread, early production units ; regarding the screw posts, there it was a matter of Chinese plastic material quality, not of the construction. The screw posts had the standard engineering construction and had thick wall thickness, even though the construction was revised in June '16 to sport even thicker wall thickness.

So I was curious how Maha's plastic material quality would hold up in comparison or the construction for that matter. Since there are no moving parts and no mechanical strain, nothing could break or crack, right? Or at least, one would not feel the need or motivation to open up the MH-C9000 for the sake of opening up.

I own a neat collection of c9k's sku244908, they are reliable for testing Eneloops (…) and recognize fully charged batteries super fast. I went ahead and first checked my reference unit from 2014. The disassembly (and reassembly) is straight-forward, one can find few youtube clips (in poor video quality) on this topic. The upper plastic case half has a total of 7 screw posts: 4 for the external screws plus 3 for the internal screws.

I was surprised that *6 out of the 7* screw posts, i.e. 85% of them, were damaged. *Cracked*, but still in place and serving. 

After examination it was clear why they had cracks. Two reasons. 
Reason no.1: thin wall thickness. 
Reason no.2: non-centric borings by the drill or tap.

I don't know if the borings were made by drilling machines or tapping machines; probably they come to existence by the roboter-automated screwing of the self-tapping screws. Either way, the borings were non-centric and due to the thin wall thickness this leads to the *cracked threaded walls *of the plastic posts.

Yes the charger construction as a whole _feels _sturdy and well-made, I must agree. The tolerances between the physicals parts (upper case half, bottom calf half, PCB, display, etc) are professionally tight, everything clicks in place with no air gaps or play. And if the borings were 100% centric, i could marvel at the precision of manufacturing and the _then _amazing build quality. But after my critical examination and fair assessment i feel disheartened: the plastic material quality _is_ cheap after all and, in fact, inferior to other ABS plastic chargers i own, the wall thicknesses are thin (at the 7 screw posts and also in the battery slots, i.e. wherever the 'concept of wall thickness' becomes apparent), and, as documented in this post, the non-centric tappings lead to cracked walls. 
:sigh:

All 7 photos are in 1088p, feel free to view in full resolution:






























I've checked other years c9k units from my collection (i entered the flashlight scene in 2011) and all of them had *6/7*, with varying degrees of crack severity. And that same number is exactly why i feel disheartened. Maybe your pre-2011 unit has only 3/7 cracked (walls in the) posts but i am herewith claiming (for good reasons kept to myself) that nobody will have 0/7, until i am proven wrong. The above 7 photos are taken with my phone, i've uploaded the pics to abloadDOTde which is FREE for anybody, i.e. anybody with a phone and internet browser could easily share proof that he has 0/7 or only 3/7.

I am guessing that the Maha production/QC/QA dpt must have been fine with this number, since the fit'n finish tolerances are so tight and cracked posts don't compromise the function and _feel _of the product, and "nobody" would open the charger for modding or repairs (since there are no moving parts) and opening the charger would invalidate the warranty anyway. Or "nobody" would care when seeing this number.

I must admit that broken posts on the other charger were an issue and that cracked posts on this charger are not an issue. Then what's the point of this post of mine? Nothing but documentation and sharing information, knowledge. You were probably not aware, didn't know, or were wondering. At the end of the week I still love my fleet of c9k's but this piece of knowledge has opened my eyes and raised my awareness.

The product is not built as well as i had pictured it from its appearance/feel.
kreisl aka "nobody". Disheartened. Desilusionado. :ironic:


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## TinderBox (UK)

The C9000 design is over 10 years old, Apart from the channels dying usually after many years of good service, I have not see any other hardware problems, If the screw posts were cracking that must have been the limit as i have not found any loose plastic rattling around any of my charger`s

Self Tapping plastic pillars have always been a cheap was of getting the job done and i have seen many device with posts split or broken off completely, machined brass inserts is the quality way to go but it`s all down to money in the end.

John.


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## kpatz

I just picked up my 2nd MH-C9000 today. I figure, with Refresh/Analyze taking ~10 hours and Break-in taking nearly 40, I can do twice as many batteries per day/week with 2. 

This is interesting though: the first one I got (from an Amazon seller), has a serial code of 0Q0GA. Based on an earlier post I found indicating that "K" in the 2nd position signified a 2011 manufacture date, that would make this unit made in 2017, so pretty much a brand-new one. The 2nd one, which I got today, I picked up at a local Batteries+Bulbs store, since I didn't want to wait for shipping, has a serial code of 0J0CA. 2010!? It sat on a shelf or a warehouse for 7-8 years? Wow... it seems to work fine though. The LCD on the 2nd (older) unit is slightly darker and doesn't have as much of a blue cast to the backlight. I don't know if any other notable differences there are, in firmware or whatever, between 2011 and 2017. The guy at the store also said the MH-C9000 was discontinued, though I don't seem to see this indicated anywhere on the internet... maybe he meant the store was going to stop carrying them.

Thoughts?


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## SweD

kpatz said:


> I just picked up my 2nd MH-C9000 today. I figure, with Refresh/Analyze taking ~10 hours and Break-in taking nearly 40, I can do twice as many batteries per day/week with 2.
> 
> This is interesting though: the first one I got (from an Amazon seller), has a serial code of 0Q0GA. Based on an earlier post I found indicating that "K" in the 2nd position signified a 2011 manufacture date, that would make this unit made in 2017, so pretty much a brand-new one. The 2nd one, which I got today, I picked up at a local Batteries+Bulbs store, since I didn't want to wait for shipping, has a serial code of 0J0CA. 2010!? It sat on a shelf or a warehouse for 7-8 years? Wow... it seems to work fine though. The LCD on the 2nd (older) unit is slightly darker and doesn't have as much of a blue cast to the backlight. I don't know if any other notable differences there are, in firmware or whatever, between 2011 and 2017. The guy at the store also said the MH-C9000 was discontinued, though I don't seem to see this indicated anywhere on the internet... maybe he meant the store was going to stop carrying them.
> 
> Thoughts?



I've had my C9000 since I don't know when, it's a 0H0BB version, and it's still working great, and as far as I know at least, nothing much has happened with it since the initial problems were ironed out.
As for it being discontinued, that seems unlikely, unless Maha has something new up their sleeves, at least it's readily available on the Maha-webshop page, as of now. Only thing they don't have and haven't had for some time is the MH-C808M, listing it as "out of stock", which is a tad strange with Maha being the manufacturer.


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## spotlight76

Is there a way to remove this from my MH-C9000?

https://ibb.co/bFB0Zmf


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## GAReed

What is that?


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## kreisl

first, let's disassemble the charger.
second, try

warm water\soapy water
oil
alcohol
acetone
vinegar
citric acide
dish washing machine's detergent powder with warm water

as solvent. if all fails, try Bar Keepers Friend as last ressort. it can dissolve all metals. hehe


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## spotlight76

I think it's from an AAA battery.


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## GAReed

Last time I saw something like that it was a NiCad, those 'hair' like strands. Vinegar first
then uses baking soda/409 to clean off the 'salts'.


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## spotlight76

Is it safe to charge a battery in this slot even if it not completely cleaned?


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## sbj

Insert the battery to be charged, then apply pressure to the negative contact with one hand so that the battery is pressed against the positive contact. Then turn (twist) the battery back and forth with the other hand. This will rub off any oxide layer at the contacts that may be present. - That should work at least temporarily.
In the worst case, the charger cancels the charging process prematurely. Much worse cannot happen (in my opinion).


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## spotlight76

I read that rechargable batteries don't leak. It looks like this isn't true, at least in my case.


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## GAReed

what chemistry?


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## spotlight76

Ni-MH, what else?


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## GAReed

Well, I've had Ni-Cd leak but not one Ni-MH in 10+ years.


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## spotlight76

Should i remove the battery as soon as it is charged? If i leave it in the charger after being charged (or about 1 hour) can this reduce the life cycle?


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## TinderBox (UK)

spotlight76 said:


> Should i remove the battery as soon as it is charged? If i leave it in the charger after being charged (or about 1 hour) can this reduce the life cycle?




Supposedly the trickle charge after the main charge ends is only 10ma so it should not cause any problems.


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## WalkIntoTheLight

AA Cycler did a trickle-charge test, to see what the long-term effects were. IIRC, it was pretty minimal, until you got up to around 100mA.


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## spotlight76

In order to see the real capacity, the best option is discharge and/or refresh-analyze?


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## spotlight76

I discharged an AAA battery , and when i charged it the capacity shown was about 90mAh less than the capacity shown when discharged. Why could this happen?


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