# Powerex Maha C9000 charger "HIGH" reading while charging NiMh AA cell



## ampdude (Apr 3, 2011)

This is kind of weird, has anyone ever gotten a "HIGH" reading while charging an AA cell? These are dreadful cells that I am charging right now, had planned on throwing them out over a year ago, but they still powered an old AA flashlight, so I've been using them. While charging them today, one of them went up to 2.15V. And then when the reading went back to that slot it said "HIGH". It did this twice. I'm just wondering if anyone has gotten this reading before? I never have. Probably gonna chuck this cell now since I have three others like it I can still use.


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## 45/70 (Apr 3, 2011)

Hi amp. I suggest you do a search for "C9000 "HIGH" using the Google/CPF only search function near the top of this Forum page.

In your case, the "HIGH" means your cells are worn out and need to be replaced. In some cases, especially when cells have gone unused for a length of time, if the cells are run through a "break-in" and or a "refresh" cycle, or two, the cells can be refurbished. You need to trick the charger into charging "HIGH" cells in order to accomplish this though.

Dave


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## Mr Happy (Apr 3, 2011)

The C9000 is telling you the cell is no good and should be replaced. However, if you have a low drain application like a mouse to use it in, you might get away with charging it on a slow charger like the Sanyo MQN05 with a low charge current.


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## Mikl1984 (Apr 3, 2011)

Another advice
Put you cells on radiator and warm up it
After that Maha accept it without additional slow charger 
But use it in low drain device


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## 45/70 (Apr 3, 2011)

Mikl1984 said:


> Another advice
> Put you cells on radiator and warm up it
> After that Maha accept it without additional slow charger
> But use it in low drain device



Excellent tip, Mikl. That is one of the ways that the C9000 can be tricked into charging "HIGH" cells. The other is to insert a "good" cell in to charge, and then quickly pull it out and replcae it with the "HIGH" cell.

Dave


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## Lite_me (Apr 3, 2011)

ampdude said:


> While charging them today, one of them went up to 2.15V. And then when the reading went back to that slot it said "HIGH".


When you first insert a battery into the C9000 and set to charge, and if you watch the display cycle through the different readouts the first time, the first voltage reading, (in your case 2.15v)... is reading the internal resistance of the battery. I'm not exactly sure what the standard is, but anything up around 2.0v would be too high and those cells might just be 'crap'.. as the term goes around here.


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## ampdude (Apr 3, 2011)

I think the cells were pretty much crap since I bought them. I'm just going to throw this one away. I was going to throw all four of them away, but I kept them only because I have been using them in my Duracell Daylight beater light that I got from Radioshack on closeout. I have three other cells and this light only uses two, so I'm just going to toss this one and hold on to the third one in case anther one goes to hell. Thanks for the info everyone!


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## HotWire (Nov 8, 2012)

The C9000 charger tests the battery impedance check before charging. If the impedance is too high the charger will read "HIGH" and refuse to charge it. Best to discard these batteries.


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## lwknight (Nov 9, 2012)

I got a " HIGH " on some Rayovac cells till I discharged them to 1 volt then they worked.
Maybe??


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## billy_gr (Oct 31, 2013)

Hi,

I am resurrecting this old thread 

It happened to me again on a pair of pretty new (about 1 year old) eneloops

This pair was used in a low power application (weather station) and it is the second time i see it when i use eneloop on low power applications.

Any ideas ? Or eneloops shouldn't be used on low power applications (clocks, weather stations, remote controls etc)


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## samgab (Oct 31, 2013)

billy_gr said:


> Hi,
> 
> I am resurrecting this old thread
> 
> ...



Try running a break-in on those cells. Eneloops should be fine in low power applications.


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## awyeah (Oct 31, 2013)

My opinion - better safe than sorry. Toss those cells and replace them. 

Sent from my Nexus 7 using Tapatalk


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## geisto (Oct 31, 2013)

X2. The charger seems pretty accurate. AAAs in my cordless phones that read HIGH were pretty much toast as far as capacity is concerned. 






awyeah said:


> My opinion - better safe than sorry. Toss those cells and replace them.
> 
> Sent from my Nexus 7 using Tapatalk


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## billy_gr (Oct 31, 2013)

samgab said:


> Try running a break-in on those cells. Eneloops should be fine in low power applications.


and because of the low self discharge they could be ideally for low power applications. Thank you sir 

One mistake in the original post: The cell is 3 years old

Brake in on the way

Let's hope that they are not counterfeit.

The whole story is the following:
I have bough 8 cells from DX on 08/05/2010 they have a fainted date code that looks like 08 xxx (didn't knew cpf back then). 

The problematic one is coming from this batch

One of my oldest pair with a date code 06 05 still works like a charm


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## samgab (Oct 31, 2013)

billy_gr said:


> and because of the low self discharge they could be ideally for low power applications. Thank you sir
> 
> One mistake in the original post: The cell is 3 years old
> 
> ...



Hmmm, I didn't realise you got them from DX. IIRC, there was a big kerfuffle a few years back about some fake eneloops coming from DX...
And I've never heard of a genuine eneloop failing the C9000 impedance test after only a few cycles and 3 years. They're normally very robust and would be still like new after 3 years and only a handful of cycles.
Well, see how you get on with them, I suppose. The proof of the pudding is in the eating, so to speak.


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## billy_gr (Oct 31, 2013)

This thread is the reason i am a bit worried... I never had an issue with the 4xAAA eneloop pack i use in my Ti calc (order from a different shop) which is again a low power device...

Let's wait 35+ hours for the brake in...


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## TinderBox (UK) (Oct 31, 2013)

Channel 2 on my c9000 stopped charging after 3 years, though it will discharge fine 

John.


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## InHisName (Nov 1, 2013)

I have used a set of AAA Duraloops for 15 months in a 'family radio' set. Approx 120 cycles and they began to go 'high'. The battery indicator had 4 positions: Full, Half, nearly empty, blank screen. What I determined was when it switched from full to half one cell was always nearly reversed. 

Because they were run 10.5 hours during the night for foster kids to waken me and not the rest of family, they'd call me for bed changes, etc. druing the night. So the switch was usually missed because all were asleep. It went to nearly dead or blank screen most times after a year of use when the end point was before waking on third day. Radio was still receiving, but could not transmit. Not good. 

At least one and maybe even two of three total cells may have reversed. Seemed the center cell was the one that usually reversed, so all three cells got abused over time. By 140 cycles, they all were reporting 'high'. I used the 'trick' to get 'high' batteries to recharge and continuted to use them in this low power device. 
I measured the drain to be 23.3 Ma, it took 42 hours to run them down when new. Three 10.5 hour nights. After the flash voltage increased to over 2.60v, the capacity began to decrease a bit. Now only 39 hours and got a reversal nearly every charge, now.

So my conclusion is; It's not the low or high drain apps that do it. It is whether you reverse a cell many times beating it up until its internal resistance increases again and again. So if your device give low bat and you are able to pay attention and shut if off in a timely manner each time, you are safe. I'd estimate that I fell into cell reversal approx 40x out of 120 cycles. 

So each of 3 cells got abused 13x each on average. So I'd guess if you could do cycles between any reversals of 3, then I might get about 400 cycles. Do it 100 apart and you mght get the FULL 1800. I cycled 2x a week for 15 months and started getting 'high' readings. I continued forcing the 'high' ones to recharge and by 18 months it ws too hard to fool the charger any more. They were all 'high' by then and deep into to it too. This was with AAA cells.


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## billy_gr (Nov 3, 2013)

Break-in results 0 1658 1535 1949

Moving on the second set


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## samgab (Nov 3, 2013)

billy_gr said:


> Break-in results 0 1658 1535 1949
> 
> Moving on the second set



Based upon your results, i cannot believe that those are genuine eneloops. Can you post some close-up photos of them please?


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## billy_gr (Nov 5, 2013)

Close up photo


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## samgab (Nov 5, 2013)

Yeah, they are definitely fakes. See that notch (or ridge) just below the positive terminal? Genuine eneloops are a smooth solid edge from top to bottom. Just one way to tell at a glance. Also explains the poor performance.


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## Yamabushi (Nov 5, 2013)

samgab said:


> Yeah, they are definitely fakes. See that notch (or ridge) just below the positive terminal? Genuine eneloops are a smooth solid edge from top to bottom. Just one way to tell at a glance. Also explains the poor performance.



Might be true for newer eneloops but the first generation HR-3UTG (and same generation Duraloops) did have a groove. The jacket sometimes bridged the groove when new but it often became more visible over time.

EDIT: billy_gr - A picture of the ends would be helpful. Also, how many times have you charged them? For 3 years old in a low draw application, they look like they've been chewed up.


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## samgab (Nov 5, 2013)

Another sign, look at the poor quality print screen alignment on the + and - symbols.


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## billy_gr (Nov 7, 2013)

@Yamabushi Total charges around 50. Blame 1) my xbox controller 2) my hobby battery holder for the appearance
One set was on the weather station for about 4-5 months (really low power)

It is still cheaper than using primaries...(even for fakes)


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## samgab (Nov 7, 2013)

billy_gr said:


> @Yamabushi Total charges around 50. Blame 1) my xbox controller 2) my hobby battery holder for the appearance
> One set was on the weather station for about 4-5 months (really low power)
> 
> It is still cheaper than using primaries...(even for fakes)



Yeah, all good.
Well, here is a pic of some genuine eneloop first gen:




Notice the layout of the instructions? Each bulleted point starts on a new line. Notice how your cells go: "WASH THEM WITH CLEAN WATER..."
-A large space between the words "with" and "clean"? Then on the original there is a line break between those same two words... 
There are definitely visible differences. But yes, Yamabushi is right, you can see the ridge at the top.
I know it doesn't matter too much to you now, having already bought them, but this info could be of use to others who either bought "eneloops" and aren't sure if they're fakes, or weren't aware of this issue, and the fact that fakes also have poor performance, so it's definitely worth getting the genuine ones.
Edit: Here's some more info about the fake ones you have.
Genuine are available for about $12 or so for a pack of 4 with free shipping these days, over in the 'States, at least. IMHO, that's pretty good value.
For Greece, or New Zealand, we have to pay a little bit more, but not that much, with places like fasttech selling 'em pretty cheap ($13.61 at time of writing after using CPF coupon code) with free shipping worldwide. I've ordered some, so it yet remains to be seen how long it takes them to arrive, and if they really are authentic, but I'm pretty sure they are.


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## Mr Happy (Nov 9, 2013)

Here is an older Eneloop (2006 vintage). It seems there have been small variations even in the genuine cells.


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## samgab (Nov 9, 2013)

Mr Happy said:


> Here is an older Eneloop (2006 vintage). It seems there have been small variations even in the genuine cells.



Interesting. I guess that perhaps that 1-800 recycle number is on the ones that were destined for the USA market? As that particular 1-800 number may be irrelevant everywhere else.
But the bullet points still each start on a new line, and the quality of the wrapper overall appears much better.


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## Mr Happy (Nov 9, 2013)

samgab said:


> Interesting. I guess that perhaps that 1-800 recycle number is on the ones that were destined for the USA market? As that particular 1-800 number may be irrelevant everywhere else.
> But the bullet points still each start on a new line, and the quality of the wrapper overall appears much better.



Yes, I definitely think the "recycle" logo is for the US market. I was more interested in the size designation of R6 rather than HR6.

There are some Japanese market batteries here that have a different recycle logo, and also don't appear to have a visible ring shaped indentation around the top. I can't find the physical batteries right now to check.

http://www.candlepowerforums.com/vb/showthread.php?201449-Souvenir-from-Japan!


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## Wolf Lonesome (Nov 16, 2013)

Well, I have an Eneloop first generation.
The cell has been found in one of the call2recycle places in Toronto.
This Enellop seems to be a genuine one like in the above post pic.
I'm not impressed at all with the Maha C-9000 cycling results.
I set the charger for three cycles:

charge at 500 mA
discharge at 100 mA

Here are the capacity numbers:
1st cycle - 1529 mAh 
2nd cycle - 1551 mAh
3rd cycle - 1543 mAh

Once again, this is not a fake battery, so I guess the capacity is pretty low.
Any suggestions how to improve the cell capacity?


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## Bright+ (Nov 16, 2013)

In my experience, you do whatever you have to do to get it to cycle, but charge them up and wait about a few days and they develop the same problem.

When the voltage across still reads 1.25 to 1.33v and MAHA reads "DONE, 0mAh, 1.28v" or something alike, you know its internal resistance building up as open voltage on cell that is actually depleted won't be that high.


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## Mr Happy (Nov 16, 2013)

Wolf Lonesome said:


> The cell has been found in one of the call2recycle places in Toronto.



Perhaps someone recycled the cell because it is old and had reached the end of its working life? Ask yourself, why would someone throw away a good battery?

Rechargeable batteries grow old and die, just like other things. The best way to get good results from an old battery is to recycle it and replace it with a new one.


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## samgab (Nov 16, 2013)

Trolling much? You're not impressed because a single AA cell, which was found at a recycling place with unknown origins and use/cycle history, and is several years old, is still performing at ~80% of its original capacity? Unbelievable. Is it the C9000 or the cell that you're unimpressed with?
If it's done 500 or so cycles, ~1500mAh is exactly the expected capacity of an eneloop. http://www.candlepowerforums.com/vb...and-compared&p=4292536&viewfull=1#post4292536


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