# AccuEvolution D Cells quality gone!



## 357mag1 (Feb 6, 2011)

*AccuEvolution D Cells quality gone! (New info see post #57)*

I have previously acquired six AccuEvolution D cells and been very happy with their performance. They seemed to retain charge well setting on the shelf as voltage would measure around 1.37V after a month.



My wife got me six more for Christmas. I seemed to be getting greatly reduced runtime when using the new batteries. Upon checking voltages the new cells where only coming hot off the charger around 1.4V, sometimes less. Cycling the cells gave little to no improvement.



The original cells on the same charger are still charging to 1.47V. 



I charged up the new cells and two of the old cells. After setting on the shelf for a week the old cells were reading 1.37V and the new cells were all down around 1.3V (range 1.29 - 1.33). 



I even charged some standard Nimh D cells and they were at 1.35V so these things appear to have no LSD properties.



I'm getting ready to send these back. Anybody else notice a drop off in new AccuEvolution D cells?


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## bigwad1 (Mar 12, 2011)

That's great to know, I just ordered some AccuEvolution D's from battery junction.
I'm having nothing but trouble with some energizer 2500 and decided to pay a little more and get the accuevolutions.
I'll do some testing when they come and see if they are any better then what you are experiencing.


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## 357mag1 (Mar 14, 2011)

Hopefully you get some good quality ones. My first batch was great, this batch is garbage.


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## secondhandsmoker (Mar 14, 2011)

Have you used them some or did they go back?


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## 357mag1 (Mar 15, 2011)

I did use them and that is when I realized there was something wrong. They were not lasting even half as long in my 6D ROP HI. The light didn't seem as bright from the get go either. A few voltage measurements and tailcap current measurements showed me the cells were not holding voltage under a load near as well as the first set. Then I started checking them off the charger and realized some weren't even getting to 1.4v which is a sure sign of weak cells.

Several cycles and they seem to be getting worse. Battery Junction washed their hands of it because it was past 30 days even though they were a Christmas present. The company has not responded to any of my emails or the web contact form I filled out.

I need to call them and see if I'm stuck with these defective cells.


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## rumack (Mar 15, 2011)

Thanks 357mag1 for bringing this to everyone's attention. I have some AccuEvolution D cells that I bought 2 or 3 years ago and love them, so I would really hate to hear their quality has changed for the worse. In fact I was thinking about buying some more but I will hold off now. Hopefully you were just unlucky and got faulty cells. Sorry that you have to go through this grief but thanks for alerting the rest of us.

bigwad1, it looks like you are our other canary in the coal mine. Thanks for being willing to test your cells when you receive them and share the results with us. I am anxious to see what you find.


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## 357mag1 (Mar 15, 2011)

That is the beauty of this forum, information sharing. I was quite disappointed with Battery Junctions lack of help. I've literally bought thousands of dollars worth of stuff from them. They haven't received an order since refusing to help. It is so much easier for the vendor to handle returns of this nature. 

I tried contacting Accupower USA as Battery Junction stated was my only recourse. No answer from my original web form. The telephone goes to voice mail anytime I call and today when I tried to send another web form it kept giving me errors stating I needed to enter required information even though all mandatory blocks had been filled. 

I left a voice mail message. We will see it this gets me a call back. At this time my recommendation is to avoid this product or buy from a reputable vendor that will take the defective products back. If you decide to use Battery Junction make sure you get your testing done within their 30 day limit.


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## AccuE (Mar 15, 2011)

A Message from AccuEvolutions Products Inc:

We are concerned that one forum member is experiencing quality issues with the AccuEvolution batteries. We are committed to providing high quality products and we take customer dissatisfaction very seriously. Please contact us at [email protected] and we assure a quick response.
Customer Service - Accuevolution Products, Inc.


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## jayflash (Mar 16, 2011)

Having recently purchased almost $200 worth of D, C & AAA AcuuE's, it would be nice to know the outcome of this problem. Is it only a bad batch or worse? I had the very same problem of decreasing capacity of new NiCd "Titanium" cells from BJ. I lost $15 in return shipping of a large order.

Hopefully the new AcuuE LSD's will prove to be good cells because it's quite difficult to test 30 cells and ascertain their quality before the seller's warranty expires. I've given up on anything "Titanium" including their flaky hi-cap charger, so I bought the Accus because of Previous CPF recommendations.


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## 357mag1 (Mar 16, 2011)

Just an update folks. I did get a return call today from Arnando at Accupower and he seemed genuinely concerned about my problems with the new batch of D cells. He stated he would send replacements and a UPS pickup for the bad cells. I will let you all know how it goes.

I'm not sure why I didn't get any response initially but things are looking up now.


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## 45/70 (Mar 16, 2011)

I hope things clear up. I've had plans for purchasing a small quantity (4-8) of "AccuE" D cells for some time. My 5 year old Powerizer D cells are showing signs of age. Their self discharge is still very low, as it always has been, however they're showing signs of voltage depression associated with age. Not a big deal, for my particular applications, but it's time for some new cells.

Dave


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## bobo383 (Mar 20, 2011)

357mag1 said:


> I'm not sure why I didn't get any response initially but things are looking up now.


 
Seems like damage control, but hopefully they're better than that. I need to buy a few D and C size, so I'm watching.


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## Canuke (Mar 22, 2011)

I'm surprised nobody mentioned the possibility of counterfeits yet. That was my first thought when I read 357mag1's description of the huge difference between his older cells and the new ones. Product quality usually slides slowly if they decide to cheap out or somesuch, rarely do they fall off a cliff like that.


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## Nubo (Mar 22, 2011)

Dang, I'm awaiting an order of a goodly number of these C and D cells from Battery Junction. Very disappointed to hear of the lack of customer support on the part of B.J.. Starting to think maybe I should have stuck with Thomas Distributing. Even more worrisome is the potential counterfeit issue. 

Are there any visual indications that these might be fakes? Is Accupower asking for samples of the defects?

Disappointing news. I've had such great results from these cells in the past.


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## jayflash (Mar 23, 2011)

I'll have to test my new batch of ten D & C AccuEvolutions which I broke in and charged 6 -8 weeks ago. They've mostly been idling in unused lights. They all met rated capacity at three cycles a couple months ago.

Keep in mind that a few bad cells don't indicate anything for sure, until further info and testing is available. I'll post my results when the cells are retested, but at only a month or two may not give the same readings as testing after 6 - 12 months.

I purchased 30 AuucE's from Bearwobble.com for less than Thomas Dist. The Bear's shipping is high, but lower cell cost more than made up. Bearwobble seems to carry an odd variety of better quality products in their respective fields.

Let's keep each other updated regarding high capacity NiMH D & C (LSD) cells.


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## 357mag1 (Mar 26, 2011)

My AccuEvolution contact called me on Thursday to see if my replacement cells had arrived. I was on vacation and couldn't tell him. Last night when we got home they were setting with the rest of the mail my daughter had deposited inside the house.

Now for the depressing part of the story. So far the first two cells appear no better than the previous batch. I have the other four charging on the Accu-Manager charger which takes longer than my Titanium MD-3000. After two cycles the highest voltage reading for these two cells hot off the charger was 1.385 so it isn't looking good.

Before going on vacation I charged all of my D cell batteries so I could check voltage when I got home. All batteries were charged on the 15th and checked last night (25th) so they have been setting 10 days. Here are the results:

1. Six original AccuEvolution D LSD - five read 1.364v and one 1.357v
2. Six new (not the replacements just received) AccuEvolution D LSD - 1.300v to 1.331v
3. Two Nuon standard Nimh D cells (3000mah rating, I suspect using a Sub C cell) - 1.34v
4. Two Tenergy 8000mah LSD D cells - 1.34V

As you can see if the AccuEvolution cells are no longer quality cells the options don't look very good. I will keep working with AccuEvolution as long as they are willing to resolve the issue.


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## jayflash (Mar 26, 2011)

Is about 1.45v or higher what you are looking for? My batch of these AccuE's have been sitting on the shelf for 60 days and now read ~1.35 - 1.38v. That also equals a 100% reading on the ZTS & ~10> "flash amps." IIRC, they we're ~ 1.42v right off the charger, two months ago.

I'm going to let these sit, retest, and check run time ... sometime. I checked the cell's capacity three times since they we're new, last January. Both, D & C sizes we're within 10% of rated capacity, using a light, .2C load. 

So far, it doesn't seem like I have a problem, unless they'd quickly deteriorate or lose their LSD qualities. 357mag1, do you plan to test run-time? Could some of your cells still be good? Is a hot off the charger open circuit voltage test convincingly accurate or might a load and capacity test after a couple months be a truer test? I'm not 100% sure, which is why I'm asking.


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## 357mag1 (Mar 27, 2011)

In my experience if they aren't reaching 1.45v coming off the charger they are lower quality cells that don't tend to hold a charge well. If they can't get to at least 1.4v during the charge cycle then they are probably garbage. Keep in mind the way I noticed these cells had a problem was much reduced runtime in my lights particularly if the batteries had set around for a few days.


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## jayflash (Mar 27, 2011)

I'll have to pay closer attention the next time I recharge my Duraloop and AccuEvo cells to check their top charging voltages. Regardless of that voltage, so far, all my LSD cells are providing near rated capacity. The Accu's are too new to know anything for sure about longevity, but the Dura's are between 2 & 4 years old, and have retained LSD qualities.


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## 357mag1 (Mar 29, 2011)

I've cycled all the replacement AccuEvolution cells about six times and now have them setting on the shelf. Hot off the charger voltage read from 1.408 to 1.431v on the 28th of March. 

I will let them set a few days and see how they measure. Hopefully they hold a charge better than the cells I had to return.


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## 45/70 (Mar 29, 2011)

357mag1 said:


> I've cycled all the replacement AccuEvolution cells about six times and now have them setting on the shelf. Hot off the charger voltage read from 1.408 to 1.431v on the 28th of March.



It seems to me that part of your problem may be the charger, rather than the cells. Even cells in poor condition should charge to voltages higher than you're getting. The voltage may then drop off drastically when removed from the charger, if the cells are in poor condition, but should typically come right of the charger at a higher voltage than what you're getting.

I'm not saying that the charger is the whole problem, but it seems to be undercharging cells. Do you have another charger to charge these cells in? It could be, I guess, that the charger, due to poor cells, is just terminating too soon. Anyway, it'd be interesting to see if the cells behave the same when charged in an alternate charger.

Dave


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## jayflash (Mar 29, 2011)

Dave expressed what I also had wondered. The charger's performance could matter. However, even if it's not reaching the proper cut-off voltage, knowing the charging current and duration of charge will give approximate results.

For example: if the cells are charged at one amp for ten hours you might expect they took in, roughly, 8Ah. After sitting for a few weeks, an open circuit voltage of ~1.35 might be an expected average, I think. Put those cells under a known load to determine capacity. That should give you some valuable info. Of course, the LSD qualities would take much more time to determine, unless there were none!

I'm using a Maha 808 which will charge at 2 amps. Would charging at 500mA create any problems provided the charger recognizes proper cut-off?


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## 45/70 (Mar 29, 2011)

jayflash said:


> Dave expressed what I also had wondered. The charger's performance could matter. However, even if it's not reaching the proper cut-off voltage, knowing the charging current and duration of charge will give approximate results.



Good points, Jay.

Thinking further about the possible charger issue, I've noticed that when charging eneloop AA cells with my C9000, that when the cell voltage initially reaches about 1.40 volts, the cells have only received about 25% of the total charge. Actually most of the charge takes place between 1.40 and 1.43, or so Volts. I'll have to observe that more closely next time. It does seem though that most of the charge takes place around 1.40 volts.

I realize that different chargers using slightly different algorithms, as well as differences between cells, may affect this voltage reading, but that still seems like a low "hot off the charger" voltage. And, as I said, in my experience, even cells that are known to be in poor condition, end with a voltage of 1.47 volt, in the Maha. In other chargers, such as the BC-900 (which don't have a Vmax of 1.47 Volt), the voltage is often over 1.50 Volts, at termination.

Dave


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## 357mag1 (Mar 30, 2011)

AccuEvolution wants me to try a different charger as well. I'm up for trying anything but here are my thoughts. Why do Eneloops and my original AccuEvolution cells come off the same charger (Titanium MD-3000, bought from Battery Junction when I still did business with those folks) at 1.5 volts or very close if the problem lies with the charger?

It seems if the charger were the problem all batteries would be coming off with a low charge. I would love this to be a charger problem but fear that is not the case. The original AccuEvolution D cells had a fairly short positive button and the new cells that are giving problems have a much longer positive button. This applies to both the ones I purchased and the replacements sent direct from the company. The performance is nothing like the older cells.

I will still hold out hope for the charge because like many of you here these were my go to D cells with LSD properties. I'm trying some of the new Tenergy D and C LSD cells along with the new Imedion D cells. So far none of them work as well as my original AccuEvolution cells.


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## alpg88 (Mar 30, 2011)

Tenergy came out with Centura lsd cells, my previous experience with tenergy nimh ws very good, i'll buy some and post results, thou i can't imagime how to test their lsd claim without waiting a year.


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## 357mag1 (Mar 30, 2011)

Here is a photo showing the difference.






The newer battery is on the left and as you can see has a much more pronounced positive terminal. 

The older batteries sometimes did not make contact in a few of my Maglites but I can easily fix that. I would take more of the older short terminal batteries any day.


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## 357mag1 (Mar 30, 2011)

alpg88 said:


> Tenergy came out with Centura lsd cells, my previous experience with tenergy nimh ws very good, i'll buy some and post results, thou i can't imagime how to test their lsd claim without waiting a year.


 
It actually doesn't take a year. The new Tenergy C and D Centura cells that I have are only slightly better than the AccuEvolution cells I'm having trouble with.

I will say the AccuEvolution C cells that I purchased at the same time as the new D cells seem to still be of outstanding quality. They charge to 1.5V or very close in the same charger.

I guess I should have stated it doesn't take a year because they drop their voltage so quickly. The Tenergy Centura D cells I charged on the 15th with the AccuEvolutions were down to 1.34 volts on the 25th. In comparison to my Nuon standard Nimh C cells charged at the same time which were at 1.34 as well. The original AccuEvolutions were at 1.364.


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## 45/70 (Mar 30, 2011)

357mag1 said:


> ......but here are my thoughts. Why do Eneloops and my original AccuEvolution cells come off the same charger (Titanium MD-3000, bought from Battery Junction when I still did business with those folks) at 1.5 volts or very close if the problem lies with the charger?


Yeah, that is a good point, 357.

While I don't remember ever experiencing this myself with LSD cells, it may be that the cells need to be cycled a few more times in order to act "normally". Looking at the comparison picture you posted though, you've got me worried. It would appear that something has changed. If the source of the cells has changed, it may very well be that the "new" ones are simply inferior. I hope not, but......

I don't use "D" size cells much, but when I do, I depend on them. I wish now that I had bought some of these earlier. As I said in a previous post, it's time for some new D cells, and now, I don't know what to get. I've never been real impressed with the reports I've seen about Imedions and their other Chinese brethren, but the AccuE's seemed to perform well. At least until now.

Dave


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## jayflash (Mar 30, 2011)

Your new AccuE cells may well be bad and I can't be positive that mine are good, yet. A little more time and testing may be necessary. I've a few more thoughts and questions.

My two MD-3000 chargers don't inspire confidence, but that doesn't mean yours is bad. The first one developed one problem after another until it failed and I returned it. The second one is inconsistent, however it's plugged into a good filter and I don't have these problems with my other smart chargers. Sometimes the MD-3000 works fine while other times it terminates early.

After sitting a month or more, a reading of ~1.34v may not be bad. If the cell provides near rated capacity without excessive voltage depression, maybe a lower "storage" voltage isn't important.

Some of my bad and oldest cells will charge to over 1.5v and old NiCds go to 1.63v. Could 1.43v be OK as long as the cells attain their rated capacity and hold ~1.25v under a load? Again, accurately determining the capacity your new Accu's retain, initially, and after a couple months will tell you everything.

As 45/70 indicated; I don't often use my D cells and they sit for months between use, I do rely on them for long run time or emergency needs. If these new AccuE D & C cells have poor LSD qualities, I'll be most disappointed because it'll take months to know that for sure and then I may have warranty issues.


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## 45/70 (Mar 30, 2011)

jayflash said:


> Some of my bad and oldest cells will charge to over 1.5v and old NiCds go to 1.63v.



Interesting about your problems with the MD-3000 chargers. Makes me wonder.

About NiCd cells, maybe you already know this Jay, but NiCd cells will _always_ charge to a higher voltage than NiMH cells. It's their chemical nature.

Dave


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## 357mag1 (Mar 30, 2011)

Dave,

You summed up my feelings exactly on the AccuEvolution and the available D cell options.

Jayflash,

I have an extensive collection of Nimh cells and it has been my experience that when cells won't reach at least 1.47v during the charge cycle they are inferior cells. This has held true if the cells are LSD or not.

You are right about testing their capacity unfortunately the only capacity checker I have is my Maha C9000 and it won't do D cells. 

Initially I cycled these cells and then started using them without doing any voltage checks due to the excellent performance I received from the original cells. I noticed right off that my 6 cell Maglite was not as bright running a 3854H bulb and didn't last near as long compared to using the original cells.

I also have a Lambda V1000 that is set up to use 3D cells. It will draw more current the higher the voltage is maintained. It drops to less than 3.5amps using these cells if they have sat for a day. The originals or a battery holder using Eneloops will give over 5amps. That is telling me they sag badly under load as well.


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## jayflash (Mar 30, 2011)

I'll have to keep an eye on the peak charging voltage for my collection of cells as that would be a simple way to flag those which may be going down hill or suddenly failed.

Might you try placing four AccuE's in your Titanium charger and press the discharge button, start a stopwatch or mark down the time. Keep an eye on the discharge and use your meter to check voltages occasionally and try to catch the discharge before it begins recharging. Multiply your times by .200mA to determine capacity. I have verified my MD-3000 discharges at the advertised rate.

After that try to time the recharge and multiply that times ~1.6A - 1.8A, which is the claimed rate. You may be able to insert your probes and check the charge current, which is what I did. That's how I noticed the charger terminated too early on occasion. It should have taken several more hours a couple times and did charge for more time when I restarted those cells.

Have you got a battery operated fluorescent light, fan, or other item which you can check the load and use it to determine cell capacity. I have several different D & C cell lanterns which consume from 1A - .300mA and use those to check the capacity of cells. You'd have to monitor light output or voltage and time and check periodically so cells don't over discharge, but I haven't had problems.

How often do you try a deep discharge down to ~.9v - 1v at a low load of, say 200mA - 500mA?


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## 357mag1 (Mar 30, 2011)

Jay,

I have flashlights I could stick them in to discharge. My lantern takes 8 cells and I only have 6 of cells in question. I've never tried deep discharging them but have used the discharge button on the MD-3000 to cycle the batteries. I usually just let it run for a four or five hours and then restart the charge process.


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## jayflash (Mar 30, 2011)

It may not matter, but it's been recommended for NiMH & NiCd cells to slowly discharge them down to a volt or slightly below. Recharge at a .5C - 1C rate or as close as you can get to that after the deep discharge This may help to restore capacity. It may be possible your bad cells may respond to several deep cycles, which is what I've done to all of mine and they perform well, so far.

Deep discharges won't do much for crap cells and, who knows, your's may have a manufacturing defect, improper chemistry, etc. I'm still hoping your cells may be OK and if not, are not typical of what AccuE's normally represent.

Thanks for communicating. I hope we can get to the bottom of this and determine the true condition of your new cells and charger.


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## 357mag1 (Apr 7, 2011)

Here is the latest on these cells and it isn't looking good. Posted below is my last email to Armando at AccuEvolution.

*Armando,

I've cycled and tested the new cells. Here is how they stack up against the old cells.

Fully charged and left on the shelf for 5 days.

Original cells voltage all at 1.375v.
New cells (with larger positive post) between 1.335 and 1.345v.

Current reading in a high current SST-50 light that will pull more current the higher the voltage (using 3 cells).

Original cells - 5.03amps
New cells - 3.54amps

Current readings in a high current SST-90 light (using 4 cells).

Original cells - 14.12amps
New cells - 10.15amps

To put this in perspective a set of Tenergy regular NIMH cells charged over a month ago had a voltage reading of 1.315volts per cell.

In the SST-90 light they managed 12.65amps.

Clearly your current LSD D cells can be outperformed by regular NIMH cells. 

Obviously there has been a change in the manufacturing of these cells possibly coinciding will going to the higher positive terminal.

At this point in time I cannot recommend these cells as their performance is less than regular NIMH cells.

Scott.
*


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## 357mag1 (Apr 7, 2011)

45/70 said:


> Yeah, that is a good point, 357.
> 
> While I don't remember ever experiencing this myself with LSD cells, it may be that the cells need to be cycled a few more times in order to act "normally". Looking at the comparison picture you posted though, you've got me worried. It would appear that something has changed. If the source of the cells has changed, it may very well be that the "new" ones are simply inferior. I hope not, but......
> 
> ...


 
Dave,

I tried to babysit some cells while charging to see what they come off the charger at but never managed to catch one just as it terminated. It appears the voltage reaches at least 1.467 on some cells. I never caught them at that voltage when the charger signaled they were done but did pull some during charging and measured between 1.447 and 1.467volts. I have walked out of the room when the charger was still in the charge cycle and come back in about 5 minutes to find the battery done. Never measured them above 1.43 or so at that time, generally less.

This would indicate the voltage drops quickly after full charge and that generally is another sign of a substandard cell.


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## JA(me)S (Apr 7, 2011)

357mag1 said:


> *Current readings in a high current SST-90 light (using 4 cells).
> 
> Original cells - 14.12amps
> New cells - 10.15amps*



A related, but slightly off topic query...

Does anyone know what the long term effect of high current discharge might have on LSD NiMH as it relates to life and capacity? 357mag, I'm not suggesting anything - I've just wondered about this for a while...

- Jas.


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## 357mag1 (Apr 7, 2011)

These new cells haven't seen much in the way of high current discharge. Just the testing that I have done. The original cells and the little Tenergy C cells were used in the Lambda SST-90 light and have seen a fair amount of high current discharge and they seem to be doing well. At least much better than the hardly used new D cells from AccuEvolution.

To answer your question though high current discharge will definitely shorten battery life and have a negative affect on internal resistance of the battery. Just goes with the territory. Almost any battery chemistry will last longer and perform better if treated gently on the discharge and charge cycle.


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## JA(me)S (Apr 8, 2011)

Thanks 357mag1. The irony of your answer lies in the reason for my query: Kevin and I are in email discussion of this very topic! (now need to ascertain eneloop viability - plausible, just haven't found evidence)

Looks like if AccuEvolution can get this sorted out, I'll join in your use of LSD in Lamda's creations (whoa man, trippin').

Sorry for the slight derailment - back to your regularly scheduled programming.

- Jas.


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## 357mag1 (Apr 8, 2011)

I just tried the new AccuEvolution D cells in my Lambda light straight off the charger. They can barely supply 12amps of current freshly charged. Compare this to the month ago charged Tenergy C cells (normal nimh not LSD) that were able to supply 12.65amps.

Armando from AccuEvolution did reply to my email and stated they are looking into this issue. Hopefully something positive (like quality D cells) will come out of all of this.

Any of you who think the new Imedion or Tenergy LSD cells might work I can say they haven't proved much better than these cells. I have two of each and would rate them just slightly better than the present AccuEvolution D cells. Not even close to the original cells.


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## Nubo (Apr 11, 2011)

I've received my order of 12 of these, along with a dozen Accu C-cells. While my charger doesn't show capacity numbers, what I can see does support the observation that these D's may be duds. When using a conditioning cycle, the C cells showed a fairly high charge (2 of 3 bars). They reached 3 bars quickly and were soon fully charged. The D cells showed a low level (1 of 3 bars) and took a long time just to get to 2 bars. Definitely not consistent with pre-charged LSD cells. 357, I appreciate your efforts in working with the company. I'm hoping they will make good on their product's promise.


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## Lanque (Apr 11, 2011)

I also have 12 Accu D-cells and 12 Accu C-cells in the mail from Battery Junction. I will do some measurements and report back once I get them - hopefully within a week. Seems the postal service is a bit slow lately.


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## 357mag1 (Apr 11, 2011)

Nubo said:


> I've received my order of 12 of these, along with a dozen Accu C-cells. While my charger doesn't show capacity numbers, what I can see does support the observation that these D's may be duds. When using a conditioning cycle, the C cells showed a fairly high charge (2 of 3 bars). They reached 3 bars quickly and were soon fully charged. The D cells showed a low level (1 of 3 bars) and took a long time just to get to 2 bars. Definitely not consistent with pre-charged LSD cells. 357, I appreciate your efforts in working with the company. I'm hoping they will make good on their product's promise.


 
You brought up another good point these newer cells take forever to charge compared to the older cells when using the AccuManager battery charger. Funny in the literature for that charger it mentions poor quality cells as a possible reason if they take too long to charge.

We will see if anything comes from working with the company. I'm still hoping we can at least get back to the quality of the original cells.


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## Lanque (Apr 16, 2011)

Yesterday (Friday) I received my 12 AccuEvolution D's and 12 C's as well as a Titanium MD-3000 charger in the mail. I also received a Maha MH-C808 on monday. 

This is my first delve into C and D NiMh cells and chargers, having used AA & AAA Enloops and Duraloops and 2 BC-9009's for some years.

Concerned about the quality of these cells, I did some experimenting. The D cells I received look like the left hand side cell in the image in post #26.

I read the voltages of 4 C's and 2 D's out the pack, under a 2 ohm load, and then after charging (hot off the charger) and resting.

I charged 4 C cells in the MD-3000 for about 2hours. The cells from the outer bays were cool on termination, but the inner two were warm. I noted that the charger was warm in the centre, and attributed the battery warmth to the charger heating up. 

After doing some voltage testing, I then charged - or at least started charging - 2 D cells on the outer bays of the MD-3000. The centre of the charger was again warm after an hour. After about 3 hours of charging, 11:30pm last night, the D cells were still cool, but the plastic in the centre of the charger was too hot to comfortably touch, and on closer inspection, I noticed that the plastic had actually deformed from the heat.  That freaked me out a bit, and I aborted immediately. I did not get to sleep for a while after the near meltdown.

This morning, I continued charging the 2 D cells in the C808. One cell (D-A2) terminated while cool after 45 minutes at 1.43V. On re-insertion it only showed 2 of 3 bars, and terminated again ~20 minutes later at 1.46V and only slightly warm. The other cell (DA-1) failed to terminate after 1h30, and was very warm (had been for 1/2 hour), so I pulled it. It read 1.44V. I am not sure how the C808 terminates, but the peak voltage due to the pulsed charge current was getting slightly lower with time, and the cell getting warmer. I do not know when/if it would have terminated, if I was being impatient, or if it was a cell/charger issue. More time and testing may shed some light.


C-cells
Voltage Load V V After 1h30 14h00 17h25 18h20
from Pack 2 ohm charge rest rest rest rest
C-A1 1.295 1.285 1.464 1.436 1.408 1.404 1.401
C-A2 1.296 1.285 1.466 1.436 1.408 1.405 1.402
C-A3 1.288 1.280 1.464 1.431 1.405 1.402 1.399
C-A4 1.294 1.283 1.462 1.436 1.410 1.404 1.403

D-Cells
Voltage Load V V After 1h10 1h30 2h15 3h00 4h15 5h15
from Pack 2 ohm charge rest rest rest rest rest rest
D-A1 1.285 1.271 1.445(hot) 1.406 1.402 1.398 1.396 1.391 1.389
D-A2 1.286 1.275 1.460 1.408 1.405 1.401 1.398 1.394 1.391


For pre-charged cells, their voltage out the pack was quite low (C and D), and the fact that the C's charged for 2 hours, and the D's for approx 3 + 1 hours, bears with the fact that they were indeed more than half empty.

Not very scientific or conclusive, what with 2 different chargers and the limited cells I tested, but the D cells do seem to sag slightly quicker after charging. Than the C's. I do not have any other C/D NiHM cells to compare these againt, so I do not know if these figures are good or bad.

The fact that the one D cell did not seem to want to terminate and was heading towards hot also does not look good.

I will keep track of these cells, and charge some more C's and D's up later on the C808. Unfortunately I do not have any equipment to measure remaining capacity, short of measuring runtime under load.

The MD-3000 is getting an early retirement after its fiasco last night. Hopefully it can go back for replacement, but i fear that with the cost of shipping it will not be worth it.


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## Lanque (Apr 17, 2011)

I charged some more D cells up this morning. They were pretty low out of the packaging. After 4h30min they started getting warm. The C808 terminated 2 cells just after 5 hours. They were more than a bit warm. After 5h20, and no termination, I pulled the remaining 2 cells before they got too hot. All cells were warmer than I would normally be comfortable with. Once again, I do not know it its the charger, or the cells, both being new.

D Cells:
D-A3: 
1.267V Out of packaging
1.249V under 2 Ohm load
5h20 till pulled - cell was very warm - heading towards hot
1.443V hot of charger

D-A4: 
1.285V Out of packaging
1.273V under 2 Ohm load
5h05 till termination - cell was very warm
 1.445V hot of charger

D-B1: 
1.288V Out of packaging
1.275V under 2 Ohm load
5h07 till termination - cell was very warm
1.456V hot of charger

D-B2: 
1.286V Out of packaging
1.273V under 2 Ohm load
5h20 till pulled - cell was very warm - heading towards hot
1.450V hot of charger

I would have pulled all the cells sooner because of heating, but was curious to see if the charger would terminate. Since all cells charged for 4h30 before any sign of warming, and charge current of 2A on the C808, I would say the
cells were fairly empty to start with.

25 minutes have passed since the last 2 cells were pulled, and they are now sitting at between 1.405V and 1.420V

C cells from Friday are at about 1.391V (3mV between best and worst) average and D cells from Sat are at 1.371V average (2mV between).

Time to go charge some more C cells in the c808 for comparison.


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## fnsooner (Apr 17, 2011)

Crap, I've been following this thread with a smug smile on my face thinking how lucky I was that I purchased all 30 of mine last year. Out of curiosity, pulled four cells out of a 4d maglight I have here in my office(Sunday night finishing my taxes). Two of the four were the newer cells per the pictures on the first page.

Luckily I marked all my Accu Ds the date of purchase. Now its back to the house to dig through all my D powered devices and do some testing of my own.

The newer looking cells were purchased 07/10 from Bear Wobble.


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## VidPro (Apr 17, 2011)

wow, what could be worse than having a bunch of lesser batteries you paid good money for, having them Be DIFFERENT and ending up using them as a team.

from what you guys are saying the reason they are getting hotter on the maha 808 style of charger, is because of the lower voltage, it is not terminating based on voltage, so termination will be based on the v-drop instead. Because the charge rate is not really high, it is probably not terminating AS quickly via the V-Drop termination, and because it isnt terminating at 90-95% charged , there is going to be the usual heat that you would get from other chargers.
And NO, i am not saying that everything will be fine, you certannly have a bad situation. i am saying that it could still eventually terminate using the other method.

And as far as the voltage goes, a very great resistance battery might not get so high of voltage on the charger, and that could be a better resistance battery, BUT this does not sound like the situation at all. it just sounds like it says in the title , they changed something, and not for the better.

for the other cooker  http://www.candlepowerforums.com/vb...nium-MD-3000-battery-cooker....I-mean-charger 
well.


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## jayflash (Apr 18, 2011)

I took my second MD-3000 apart because one channel quit working. My first MD had several problems before failing entirely.

I had to resolder the negative lead to the spring loaded contact. I noticed the power device which is centrally located on a small, flat, heatsink, had separated from it and had no thermal compound. I forced some between the two and shimmed them to, hopefully, keep them together when the charger is screwed back together. 

This charger will randomly terminate on different channels at different times even when all cells are equally discharged. I have to restart to finish charging, sometimes. This is the second unreliable MD-3000 and not worth the $40, IMHO.


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## fnsooner (Apr 18, 2011)

Here is a follow up from a couple of posts back. 

When I purchased my last ten Accu Ds, it was in 07/10, around nine months ago and these were the newer style. I decided to charge all of my D cells including the twenty I purchased around 01/10(these were the older style). So all thirty cells were completely charged 07/10/2010. 

So I go home last night and pull six cells from my 6D maglite that is mounted next to my bedroom door. I have tons of flashlights and this maglite has been relegated as a glorified battery carrier and club. Except for checking that it is working, I have not used it since charging the batteries nine months ago.I check the voltage on these
batteries and I get a range from 1.30 to 1.31VDC. Remember these cells are the new style.

So now I pull six batteries from a battery pack that plugs into a Coleman tent fan and the fan had not been used since charging the batteries. Surprisingly enough they have a voltage range of 1.30-1.31VDC. These are the old style cells purchased in 01/10.

So I take four of the new and four of the old style and put them in my Maha MH-C808 and start a conditioning cycle. The Maha manual says it could take thirty hours to finish this cycle. Hopefully I will be around when it is finished so I can check the voltage on all cells. One thing I noticed is when the initial stage of the conditioning, all batteries were charged and they all finished this charge stage within ten minutes of each other in about an hour or so.

These are just the facts as I find them. I'll leave diagnosing to you guys. I plan on running all thirty through a conditioning cycle, then check the voltages in a month. Any other testing suggestions.


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## jayflash (Apr 19, 2011)

The ~1.3v seems normal for NiMH LSD cells stored since 7/10 and the fact they all charged up within 10 min. may be a good sign. What I'd have done first, and plan to do soon with mine, is to discharge my stored Accu's and record their capacity. Next, I'll charge them at the 2A rate in my Maha 808 and record the time and voltage for future reference. 

The 10 D & C Accu's I've got will have only been stored about 2.5 months, so whatever LSD properties they have won't be as apparent as a longer storage time. I'll post when the results are complete. May I suggest first discharging cells with a reasonable load first and check voltages periodically? Good cells will plot a very gradual drop in voltage which is handy to record on graph paper for us low-tech type.


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## Fresh Light (Apr 19, 2011)

The transformer on my md-3000 failed, the charger still worked on the 12v plug. BJ sent me a new transformer, however it did not work out of the box, nor did it test to have any voltage. They sent me another transformer and i've been using it since. I've only charged TiD's and TiC's and Tenergy C's. I'll have to check the voltages, but i don't remember seeing anything as higher than around 1.35. Yeah the cells get pretty warm after charging, but it seems to work fine and the cells have always charged ok.


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## Rezolution (Apr 19, 2011)

This thread is really depressing to me 

I've been trying for a week now to find the discharge curves of 3 different LSD NiMh D batteries that were my choices (Imedion, Tenergy Centura, and AccuEvolution). Imedion are the most expensive and I cannot find a spec sheet for them that has a discharge curve with useful information on it. Tenergy Centura were the cheapest. I originally wanted LSD type since these are going into my 4-cell D-cell maglite with a current regulated P7 in it. It has a continuous drain of 2.8A at about 3.7V.

I have some D-cells that I ordered from Ebay China that are rated at 10,000maH and only perform at 4,000maH and those are going to go in the garbage when I can get some good replacements. 

I was going to get 4 of these AccuEvolution batteries but after reading this thread, there is NO WAY I'm buying them. 

Should I go with the super expensive Imedion from Maha or should I just get plain old Tenergy (non-LSD). I just need a good set of batteries that will give me a long run time. I don't see the flashlight ever sitting for more than a month. Since all of the LSD batteries in D size are getting terrible reviews, does anyone have a recommendation for me?


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## fnsooner (Apr 19, 2011)

My cells finished the conditioning cycle, but I wasn't able to check voltage fresh off termination. You all will have to exuse my rookie attempts to trouble shoot these cells.

This weekend I am going to initiate a more systematic aproach to this. 

But in the mean time.
My 6D mag has a 600 lumen terralux drop-in in it and last night I had one set of six charging while the other set of six were being depleted in the maglite. I didn't take notes but was checking amp draw on the mag when I put fresh batteries in it. I was getting 2 amps initially on both sets of batteries but it rapidly dropped off to around 1.85 amps. 

I also checked voltages (kind of hap-hazardly) when the done signal displayed. I was getting 1.4-1.5VDC. None of the cells were getting hot although the right end of the Maha charger was getting warm and transfering the heat to the far right battery, I think. 

Some of these numbers don't really mean much to me, but what pops out is that the new and old style cell numbers seem similar.


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## HarryN (Apr 19, 2011)

Hi, you need to use some care when comparing different cell sizes to each other. For an equivalent level of technology, cell mfgs have to make a decision - optimize discharge rate, or capacity.

The r/c crowd has tended to push the Sub Cs more toward discharge rates, and the smaller diameter helps with heat removeal.

Ds tend to be pushed more towards capacity, partly because that is what people tend to think of when they buy a D vs a sub C, and heat removal is a lot harder.

Some of you mentioned that you didn't have a good way to test for discharge rates, but that is actually easy to solve, since you must have a good voltmeter there to be getting this very nice data.

Consider testing each cell individually by discharging it through a resistor network. Assuming that the goal is to discharge them in the 5-10 amp range, then 1.xx volts wil need either 0.2 ohms or 0.1 ohms.

I would like to suggest building this up from 1.0 ohm resistors such as this one:

http://www.newark.com/rcd-resistors...0-fbw/resistor-wirewound-1ohm-5w-1/dp/42K5286

The are about $ 1 each at newark in case the link doesn'tt work.

It is basically a reasonably high precision 1 ohm wire wound resistor with a 5 watt (each ) rating, in an axial format. 5 of these in parallel are 0.2 ohms, and 10 of them are 0.1 ohms. These are easy for anyone to make into a bundle or mount on a simple perf board, soldered or not.

Just set this up with your cell discharging through it, and measure the voltage drop through the resistors. Using V=IR, you can calculate current, and draw up a simple table of results.

Even if all of the results are different, at least you can sort your cells to match them as sets if you like.

I have read through this thread several times, and still can't tell if this is a cell problem or a charger problem.


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## alpg88 (Apr 19, 2011)

wow, i did look up imedion, $37 for two!!!! did anyone try them, are they so much better than everything else, is it really worth $37 a pair?


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## jayflash (Apr 19, 2011)

"I was going to get 4 of these AccuEvolution batteries but after reading this thread, there is NO WAY I'm buying them. " 

" Since all of the LSD batteries in D size are getting terrible reviews, does anyone have a recommendation for me?[/QUOTE]"

1) We don't know for sure that the Accu's are generally bad. So far my experience is different, but I must retest my batch of C & D LSD cells. It could be that a bad or mistreated batch was purchased by Mag.

2) ARE all LSD D cells poorly reviewed? So far mine are holding up, but they're only a few months old and I'm going to retest them.

3) HarryN has emphasized the same thing I've been after. We should determine the capacity and voltage of these cells after some time for more accurate understanding of their quality. Harry's set up is good, but you may use something like a lantern or battery fan, etc. and check the discharge current and voltage several times to see if it changes. It's likely a higher drain will exist at first and reduce somewhat as the voltage drops, but you should be able to get a general idea of a cell's capacity.


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## 357mag1 (Apr 19, 2011)

*UPDATE!!!*

I purchased a cheap Accucell 8150 hobby charger so I could better understand what is going on with these cells. I feel the information was important enough to this thread to warrant posting immediately.

I had the new and original cells setting after being charged 10 days ago. I started discharging at a 2amp rate and the new cells are actually testing out approximately 400mah to 600mah GREATER capacity than the originals.

Now everyone is probably wondering why I came on here complaining about the quality of the new cells. I still think they stink!!! We gained a little capacity but sacrificed the ability to maintain voltage under load. My lights were enough dimmer using the new cells compared to the originals that it led me to believe these batteries were almost dead and needed recharging. Voltage readings appeared to agree.

How bad is the voltage drop under a load compared to the originals? Bad enough that in my Lambda SST-50 Maglite with freshly charged cells there is over 2amps difference measured at the tailcap. Huge difference in output. Even a relatively low draw light like the Mag Charger Ican (using an extension to allow five D cells) is appreciably brighter with the original cells.

Bottom line if you use the AccuEvolution cells in lights like a TK50, Malkoff Maglite dropin, or the Mag LEDs you will probably be satisfied with these batteries. If you need them for direct drive LED lights or Icans you will probably be disappointed. The new Tenergy LSD cells act just like these new AccuEvolutions coming off the charger but maintain their voltage under load as well or better than the original AccuEvolution cells.

Just one more example of how bad these new cells are under a load. I set the Accucell to discharge at 5amps with a cutoff voltage of .8V and the new cells that were charged 10 days ago almost immediately cause the discharge to terminate because they have dropped below the cutoff voltage. The original cells charged at the same time don't do this.


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## jayflash (Apr 19, 2011)

Thanks for the update. I agree that a little more capacity isn't worth noticeable voltage depression. When I finally test my batch I'll post the results. My hope is still that you've got an abnormal bunch of new cells and the manufacturer replaces them.


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## Mr Happy (Apr 19, 2011)

There's a slight puzzle here with regard to capacity and discharge rate. Consider that an Eneloop (AA) has a moderate capacity of 1900 mAh and a comparatively good discharge rate (up to 5 A is comfortably achievable). Then consider that a D cell has approximately 7x the volume of an AA cell. So using similar technology, we might therefore expect a D cell to have a capacity of 7 x 1900 = 13 000 mAh and a discharge rate up to 7 x 5 = 35 A. It is notable that real D size NiMH cells rarely get close to that. Either there is insufficient market for anyone to make them, or there is some kind of patent encumbrance that prevents them being made.


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## 357mag1 (Apr 19, 2011)

Mr Happy makes a good point. By the way I did try a standard Eneloop AA at the 5amp discharge rate and it lasted longer than the big AccuEvolution D cell before the charger terminated the cycle. That is compared to the new cells, the originals lasted much longer than the Eneloop.

I also just discharged one of the new Tenergy Centura LSD D cells. It holds voltage better than the original AccuEvolution cells (at least this single cell did) and had a capacity of 8901mah. Not bad for a battery listed as having 8000mah.

The highest capacity I've recorded on the original cells after a day off the charger is 8907mah. All of the original cells seem to run between 8800 - 8900mah. The new cells average 9350 - 9600mah.

The one Imedion tested so far had a capacity of 7759mah but it was charged 10 days prior. It doesn't hold voltage under a load much better than the new AccuEvolution. 

I only have two cells each of the Tenergy Centura and Imedion so my testing is limited.

The Centura is actually starting to look pretty good which is surprising as voltage readings were only slightly better than the new AccuEvolution cells. I will test some more but they appear superior to the Original AccuEvolution when it comes to maintaining voltage under a load. 

Maybe all is not lost yet. It doesn't hurt that these Tenergy cells are cheaper than the AccuEvolution cells.


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## 357mag1 (Apr 19, 2011)

jayflash said:


> Thanks for the update. I agree that a little more capacity isn't worth noticeable voltage depression. When I finally test my batch I'll post the results. My hope is still that you've got an abnormal bunch of new cells and the manufacturer replaces them.


 
Unfortunately these new cells I'm working with are the replacements they sent me. While I did not have the hobby charger at the time and didn't have a handy way to discharge them they acted exactly like these cells. 

I charged up the new cells and threw them into a light expecting them to work like the old cells. Having a much dimmer light clued me into the problem.


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## jayflash (Apr 20, 2011)

That's most unfortunate. I wonder if my BearWobble batch is the old or new type; it's hard for me to tell from the appearance of the positive nib.

I sure hope it's a bad batch rather than manufacturing change, otherwise our choices for good LSD C & D cells is extremely limited.


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## rumack (Apr 20, 2011)

Has anyone contacted AccuEvolution with this new info (slight capacity gain but significant decrease in performance under load)? I would like to see their reaction.

I wish I had purchased more of the AccuEvolution cells a couple years ago. It sounds like my uses wouldn't tax the new cells but I don't like the perception that the new cells are inferior. At the very least I wouldn't want to mix them.

My thanks to those with the technical expertise to evaluate these new cells. Maybe one of these days I will know enough to be able to help out too.


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## fnsooner (Apr 27, 2011)

I decided to follow 357mag1's lead and ordered a Accucell-8150 hobby charger. It just arrived today. I scrounged up a 250w power supply from a junked computer to convert to a 12v power source. 

I have always wanted a hobby charger but I have never had a specific need, so I never could figure out what kind, or how powerful of a charger I would need. 

Now I need to figure out how to use it.:duh2:


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## BILL G (Apr 27, 2011)

I also have a ACC 8150. It is a good charger. I think you will like it. Yes how to use it can be a slight problem. Have you DL the manual from HOBBY KING website? I use a 15V 8 Amp laptop charger for a PWR Supply.


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## KiwiMark (Apr 27, 2011)

fnsooner said:


> Now I need to figure out how to use it.:duh2:


 
That's only a problem when you are not familiar with the charger, you'll be amazed at how quickly you get the hang of it and before you know it you'll be thinking that it isn't all that complicated.

The 8150 is a great charger for the price, plenty capable enough for charging damn near anything.


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## 45/70 (Apr 28, 2011)

fnsooner said:


> I have always wanted a hobby charger but I have never had a specific need, so I never could figure out what kind, or how powerful of a charger I would need.



fnsooner, hobby chargers are indeed handy to have around. Keep in mind however, that if you plan on charging NiMh cells in series with a hobby charger, it's really best to charge at a 0.1C rate. You can get away with charging at a 0.5C rate, but your cells will likely not last as long, due to overcharging of some of the cells. Of course, if you plan on charging only one cell at a time, there's no problem.

I reserve my hobby charger for charging Li-Ion and Pb cells and batteries. The only time I use it for NiCd, or NiMh cells, is when charging welded, or soldered battery packs. Then, most of the time, I utilize a 0.1C rate. As an alternative, I charge these packs at a 0.5C rate until the pack first begins to get warm, then reduce the charge rate to 0.1C for a couple hours, or until the charger terminates the charge. This helps to alleviate any overcharging of individual cells in the pack that may otherwise occur.

Dave


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## jayflash (Apr 29, 2011)

Here's an update with more questions with some info. After initial break-in, back in February, and four complete conditioning cycles in a Maha 808 the Accu D cells showed 1.36v @ 30 day rest. Hot off charger they had 1.43v, 1.41v @ 24hr rest & 1.40v with 48hrs. rest. All dumped 11 amps into a short.

I'm hoping an electrical glitch stopped the condition cycle at 20 hours and reset the charger to the 2A charge mode. 20hr X .25A = 5Ah which is 1/2 of rated capacity. Recharge time was four hours so, considering inefficiency, capacity was maybe ~6Ah - 6.5Ah? Another careful test is needed because earlier readings were closer to the rated 10Ah capacity. These are all the "older cells" with the shorter + nib.

After 60 days my batch of Accu C cells show 1.35v and also deliver 11 amps into a short.


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## jayflash (Apr 30, 2011)

The AccuEvolution C & D cells don't seem to have any LSD qualities. After only 30 & 60 days of storage some of the C cells and one D have only ~3Ah capacity at only a .25A load. I'm going to retest them, soon, using a higher load and again at .25A to compare. Then ... who knows. A letter to the manufacturer and BearWobble to let them know of the cells' performance.

Unless I've made a mistake, it seems like these cells are no better than high capacity NiCds, or worse. If these cells were properly produced at one time, why this giant step backwards? I've had 20 Hi-Cap NiCds from Radio Shack in the past 20 years that all lasted from 8 - 10 years. Are more manufacturers just making more junk at high profit these days?


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## fnsooner (Apr 30, 2011)

BILL G said:


> Have you DL the manual from HOBBY KING website?


 
Done. Thanks.



45/70 said:


> fnsooner, hobby chargers are indeed handy to have around. Keep in mind however, that if you plan on charging NiMh cells in series with a hobby charger, it's really best to charge at a 0.1C rate. You can get away with charging at a 0.5C rate, but your cells will likely not last as long, due to overcharging of some of the cells. Of course, if you plan on charging only one cell at a time, there's no problem.
> 
> 
> Dave


 
I only plan on charging one cell at a time. I purchased this hobby charger to test these Accu D cells and I have a long ways to go before I can even think about charging multiple cells. I have a La Crosse Technology BC-9009 charger to analyze and check capacity for my AA and AAA nimhs. Now I can do the same to my nimh Ds. I also have a couple of Li-on powered flashlights that I keep charged with the Pila charger. I can now do more than just charge them.

I am in no way considered a power user when it comes to batteries and can't really justify 90% of the things I buy that are CandlePowerForum related. For some reason or another these new LED flashlights and their power sources interest me.




KiwiMark said:


> That's only a problem when you are not familiar with the charger, you'll be amazed at how quickly you get the hang of it and before you know it you'll be thinking that it isn't all that complicated.
> 
> The 8150 is a great charger for the price, plenty capable enough for charging damn near anything.


 
Thanks for the encouragement. I finally got my power supply working, equipped with binding posts and an on/off switch. It is now time to get the instruction manual out for this hobby charger and try some things. I think the first thing I will do is to do a discharge and charge to check actual capacity on six old style and six new style AccuEvolution D cells. Then I will do some stress tests similar to the testing done by 357mag1.



Any guidance will be appreciated. At what rate do you guys think I should charge and discharge these cells? I bought some Neodymium magnets to attach the alligator clips from the charger to the battery. Is this a good enough connection to do the things I am attempting?


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## jayflash (Apr 30, 2011)

Theoretically, using the .2C discharge, .5C - 1C charge rates used for 2Ah AA cells, two amps discharge and five amps charge current might be tried given the assumed 10Ah capacity of the D cells. I'd be more conservative and cut those values in half because of possible cell heating while charging and the cells may have only half of their rated capacity. Try a load of .5A - 1A as a starting point and charge at least @ 2A - 3A to keep the chemicals well distributed and so-called "crystal" size to a minimum.

I'm not sure I'd trust any magnet to pass several amps and wonder whether its resistance might fool the charger, but others are more experienced and can advise you on their use. I use different size battery holders and maybe you can salvage some from old radios, etc. Good luck and keep us posted with your results.


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## Mr Happy (Apr 30, 2011)

Generally speaking I don't think it's wise to follow the 0.5-1C recommendation for charging high capacity C or D cells. As with jayflash I would keep the charging current to about 2 A max, even with a 10 Ah cell.


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## fnsooner (Apr 30, 2011)

jayflash, Mr Happy, thanks for the advice.


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## 45/70 (Apr 30, 2011)

fnsooner said:


> I......can't really justify 90% of the things I buy that are CandlePowerForum related



Imagine that. I've never heard of such a thing. 



Mr Happy said:


> Generally speaking I don't think it's wise to follow the 0.5-1C recommendation for charging high capacity C or D cells. As with jayflash I would keep the charging current to about 2 A max, even with a 10 Ah cell.


 
I agree. I'm not too sure about LSD "D" size cells, but most "traditional" D size NiMH cells have a max recommended rate of about 0.3C. My Powerizer D's (from batteryspace) for example.

Dave


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## Mikl1984 (Apr 30, 2011)

Mr Happy said:


> Generally speaking I don't think it's wise to follow the 0.5-1C recommendation for charging high capacity C or D cells


You are wrong 
Usual recommendation from manufacturer for C and D cells (fast charge) is 0.5C
I have pdfs from Ansmann for example
C - 4500mAh 5035352 http://www.hy-line.ch/fileadmin/HY_LINE/Dokumente/Ansmann/Akkus/5035352.pdf
D - 8500mAh 5035362 http://datasheet.octopart.com/5035362-Ansmann-datasheet-5332059.pdf


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## My2Cents (Apr 30, 2011)

I usually follow the manufacturer's recommendation for the battery.
AccuEvolution D recommended charging rates are printed on the battery label.
Standard 12h/900mA or 5h/2000mA for fast charge.
Any charging rate between standard (or slow) and fast should be ok.
I use slow most of the time to keep battery around longer.


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## Mikl1984 (May 1, 2011)

My2Cents said:


> I usually follow the manufacturer's recommendation for the battery.


Abs agree
But 
1. Accuevolution isn't maker of its product. They ordered products from different real makers, such as GP. http://www.gpbatteries.com/html/techinfo/nimh.asp 
2. It's rather interesting doc http://accuevolution.com/pdf/NiMH AccuEvolution D 10000 mAh.pdf They point 2000mA, but don't provide charging curve for this mode  I am not sure, that on 0.2C will be distinctive -dV. With hobby charger you may check it of course.

Recommendation from GP 0.2-0.5C. But even on 0.5C you don't see real -dV http://www.gpbatteries.com/pic/1000DH TDS ZRS5024.pdf


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## My2Cents (May 1, 2011)

I will be able to add more data as I still have some AccuEvoltion D cells from 2008 still in use.
Have some newer ones on order and while waiting for delivery, I'm running quick capacity check on the older ones.
Those results can then be compared when I also do capacity check on the newer ones.
This should give us idea on how much is lost over time.


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## Groundhog (May 3, 2011)

Rezolution said:


> This thread is really depressing to me
> 
> I've been trying for a week now to find the discharge curves of 3 different LSD NiMh D batteries that were my choices (Imedion, Tenergy Centura, and AccuEvolution). Imedion are the most expensive and I cannot find a spec sheet for them that has a discharge curve with useful information on it. Tenergy Centura were the cheapest. I originally wanted LSD type since these are going into my 4-cell D-cell maglite with a current regulated P7 in it. It has a continuous drain of 2.8A at about 3.7V.
> 
> ...


 
ThomasDistributing has a decent deal on the NexCell EnergyOn LSD batteries in C and D sizes. They are probably crap but they are less than $15 for a 2 pack. The price is right even if the quality ain't. Not exactly an ideal solution. 

I couldn't resist ordering a few of each, so I'll be interested in seeing how my EnergyOn's compare with these Evolution's and the Powerex's I currently have.

UPDATE - Just got my EnergyON's but have decided to return them. Given the results seen here (and after inspecting the EnergyOn batteries in person) I decided to return them for some Imedions. ThomasDistributing was extremely gracious in dealing with me. They've gained a loyal customer.


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## InHisName (May 3, 2011)

Groundhog said:


> I couldn't resist ordering a few of each, so I'll be interested in seeing how my EnergyOn's compare with these Evolution's and the Powerex's I currently have.


I ordered NexCel EnergyONs Jul '09 and found the AAA lasted 50-65 cycles before HIGH. My AAA Duraloops lasted slightly longer approx 70-90 cycles. The LSD, charging, capacity,etc seem to be pretty similar.


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## jayflash (May 3, 2011)

Another Accu update. After charging 10 D cells with the Maha 808 I let them sit for two days and discharged six @ .5A & four @ .4A, both had only 7Ah capacity. This is after five charge/discharge cycles. I'll check the peak charge voltage again, but it was only about 1.43v the last time.

I'm recharging six in the Maha and four in a Titanium MD-3000 which outputs ~1.6 - 1.8A. The MD charged some Accu C cells to 1.48v which is higher than the Maha. Retesting the C & D cells will be necessary, but now I wonder whether the Maha is fully charging -- it usually stops at two hours for soft chg. with Duraloop AA's.

So far, unless more cycles are needed, it seems these Accu's have no LSD qualities whatsoever. Another test in several months may prove this, but I'm thinking enough info's been collected to contact the manufacturer or seller. Any opinions? I plan to test my 10 C cells soon, perhaps that will answer some questions or create more.


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## jayflash (May 3, 2011)

deleted goof


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## My2Cents (May 4, 2011)

Capacity check on older Accu Ds should be done and posted this weekend.

Meanwhile... Anyone notice that battery states 900mA for 12 hours but accu website shows 950mA for 12 hours ? Looked at the ones I have and it all show 12h/900mA. Maybe a newer one is coming ?

Also fast charge is different.

Perhaps there's 2 different versions of the this battery ? A "12h/900" and "12h/950". This might explain the difference in quality.


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## My2Cents (May 9, 2011)

Based on discharge test on old cells, it is also possible that you received old stock.
These batteries do not have any production date or lot number.
IMHO, a manufacturer who is confident about the quality and/or consistency of their product will use some form of tracking code in case something is not up to par.


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## jayflash (May 14, 2011)

After numerous tests since last February, the ten AccuEvo D & ten C cells are all close to one another in specs, like Duraloops, so that's a good start. Initial testing after break-in showed all cells close to specs in capacity. After sitting 30 & 60 days they had, roughly, half of their capacity. Retesting a couple days after a full charge, the D cells had about 8.5Ah with a .5A load. 

The Maha 808 charged them to a peak of 1.49 volts, while a Titanium MD-3000 hit 1.52 volts. The MD charged fully charged cells from the Maha for another hour. While I'm still concerned about the poor showing for LSD properties, might the Maha be undercharging?


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## jayflash (Jun 7, 2011)

Warmer weather and the outdoors have me busy on other maintenance because summer is short in Two Rivers. Here's a brief update on my slow testing progress.

Latest test on the AccuEvo C cells indicate about 3.5Ah capacity after sitting a month. The discharge curve is quite flat and they reach 1.47v immediately off charge with 1.49 - 1.52 peak charging volts. I'm letting the D cells sit for awhile longer to be more certain whether they have any LSD properties. This is time consuming and that makes it harder to get around to.

Any info from others regarding C & D LSD cell testing?


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## LEDAdd1ct (Jun 7, 2011)

I have some AccuEvolution "D" cells which I would very much like to charge on my new Bantam BC8DP. My dad and I are going to craft some charging wires this evening, so I may have something substantive to contribute in the near future. :thumbsup:


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## Groundhog (Jun 9, 2011)

I didn't note the date I recharged them, but I've been checking the voltage of some C and D size Powerex and Imedion. They were charged about a month ago on a Maha 808. Using a BK multimeter to check voltages.

Pretty stable results so far. Down to about 1.285v on the Powerex and 1.335v on the Imedion for both sizes. Results very stable across and between C and D sizes (rare for a reading >.002v variance from avg).


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## 357mag1 (Jun 9, 2011)

Hope your new Imedion D cells check out better than mine. The Imedion cells I purchased are much like the new Accuevolution cells. They have excessive voltage sag under even light loads. A 2amp load will drop them down almost .1 volts under the original Accuevolution cells. This makes a huge difference in any Ican in the ROP low range or higher current draws. You probably won't notice it running a TK50 or Malkoff dropin though the lower voltage will increase current draw and deplete your cells faster.


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## Groundhog (Jun 9, 2011)

Unfortunately my Imedions likely have the same magic smoke inside them as yours. I didn't notice a manufacturing lot on my batteries so kinda hard to compare. Maybe I didn't look hard enough.

I have 4 more D's and 2 C's that should have been delivered today so I guess I should to do a proper test starting this weekend. At least I can get an idea of how quickly they discharge vs Powerex.

Haven't considered testing them under a load. Makes sense though.

Will be using the cells with Malkoff 3-6D Maglite drop in, portable radio, maybe a LED camp lantern and other general/emergency use.


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## 357mag1 (Jun 9, 2011)

For that use they should work fine but I would have saved a bunch of money and bought the Tenergy LSD D cells for a lot less money and they hold up under a load better. Almost as well as the old (Good) Accuevolutions.


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## LEDAdd1ct (Jun 10, 2011)

LEDAdd1ct said:


> I have some AccuEvolution "D" cells which I would very much like to charge on my new Bantam BC8DP. My dad and I are going to craft some charging wires this evening, so I may have something substantive to contribute in the near future. :thumbsup:


 
Well, I pulled three of the "D" cells I have, and tried discharging/charging them on the BC8DP. Regardless of the health of the cells, I can say that it will be very hard for me to go back to a charger that does not offer a detailed readout! Being able to watch the temperature, charge current, amount of charge put in, etc. is absolutely amazing, and having such control over the parameters is addicting. 

The first couple discharge/charges on the cell did not get very far at all. I did a two amp discharge, and four amp charge, since 4aH is a little under 0.5C @10aH total. I tweaked the type of charge to "Reflex," and the cell seemed to like that better. I am not entirely sure what makes this algorithm different than a "regular" charge, but it took much more current before reading full. When I try the other two cells, I will install all three in my favorite 3D lantern and report back on their capacities and other stats, as well as whether the light remains constant instead of immediately dropping off as it had before.

After discharging one of the questionable batteries at one amp, I am now slow charging it at only 900mA. I'll report back when the charge completes some time next year. I am hoping the slow rate will help to "form" it as they say, and restore it to full capacity. I am hoping that after a prolonged period of inactivity, discharging the cell and then slow charging it can help to bring the capacity back up to snuff. Whether it will hold that under load...?

EDIT: Well, it's official! I am thoroughly confused. This site here suggests a slow charge is good for forming, and for bringing cells out of storage. This site here states that "...to begin with, the NiMH produces a very small voltage drop at full charge and the -dV is almost non-existent at charge rates below 0.5C and elevated temperatures."

So, if I am trying to revive these "D" AccuEvolution cells, am I better with the 900mA charge as printed on the cell label? Or, am I better going with the 0.5C at 5aH? Or, am I better off discharging the cell completely, and putting it in an old, dumb, timer charger until enough hours have elapsed to reach 10aH?

If it helps, I checked the picture earlier in the thread, and my button tops are shorter, like the cell on the right.


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## ufokillerz (Aug 15, 2011)

hate to bump a old thread, i just got some Accuevolution D batteries from bearwobble recently, and the cells come off my Maha C808 @ ~1.47, after a week or so, they were about 1.37, these are the newer style cells with the taller button


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## Zyban (Aug 16, 2011)

Awaiting for my AccuEvolution by Accupower D Cells 10,000 mAh to arrive tomorrow to start testing. I ran across some AccuLoop by Accupower D Cells today while searching again for a spec sheet for my old CTA 12,000 mAh cells (no luck). The AccuLoops are rated at 8,500 and are LSD with the part number AL8500. Found them on onlybatteries dot com (they carry both AccuLoop and AccuEvolution D cells) and can only find them listed on Accupower's international websites.

I first thought maybe AccuLoop was a non-USA brand since it isn't on the Accupower USA website, but Thomas Distributing carries both AccuLoop (AA/AAA) and AccuEvolution (C/D/9V) on their website. AccuEvolution with the higher capacity is marketed by a Michigan company in the USA with a partnership with Accupower in Austria. The spec sheet does show the AccuEvolution with the 10,000 mAh rating is a slightly larger diamter and heavier battery, so I doubt it is just a matter of rebranding with a new rating.

Any thoughts?


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## gbcox (Aug 19, 2011)

Well crap... been looking around for a few days for rechargeable Ds and settled on the Accuevolution; then I read this thread after I've ordered from Bear Wobble. Will let you all know what I find... I'm hoping that all will be good, but after reading this thread I don't think I chose wisely... :sick2:


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## gbcox (Aug 24, 2011)

Received my shipment from BearWobble today. Looks like the ones with the shorter positive terminal - but the top of the battery is somewhat flexible, so not sure if that really means much of anything. The initial voltages out of the box ranged from 1.317v to 1.321v. I'll running half through my Rayovac Sportsman Lantern to test, then charge up and take a few readings. I'll then create and post a spreadsheet with the findings. The batteries say 1.2v - so anything at or above that is what to expect, right?


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## Mr Happy (Aug 24, 2011)

gbcox said:


> The initial voltages out of the box ranged from 1.317v to 1.321v. I'll running half through my Rayovac Sportsman Lantern to test, then charge up and take a few readings. I'll then create and post a spreadsheet with the findings. The batteries say 1.2v - so anything at or above that is what to expect, right?


1.2 V is completely empty, somewhere around 1.35 V is fully charged but this varies a bit depending on the particular brand of battery. 1.32 V out of the box is a good sign especially if all the batteries had similar voltages. Low (< 1.2 V) or uneven voltages out of the box is usually a bad sign.


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## 357mag1 (Sep 12, 2011)

I received my TK70 this past week providing another test platform for the various D cell batteries in my collection.

In the turbo mode this light draws right around 8.5amps at the tailcap using the original AccuEvolution, Tenergy Premium, or Centura cells. 

The new AccuEvolution cells with the larger positive button drew 9.7amps on turbo. This is a regulated light so the higher current draw indicates the batteries voltage sags much worse than any of the other rechargeable D cells.

I have found there is some variance in the quality of the Tenergy Centura cells as well but nothing as drastic as these new AccuEvolution cells.

The Imedion D cells are not much better.

The only LSD D cell I would recommend at this time is the Tenergy Centura. The Premium seems to work even better under higher current loads so consider them if you don't need LSD qualities.


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## rich05uk (Oct 9, 2011)

Hi all, I've been watching this thread with interest as I'm just about to order a TK70 and will need to order a load of D cells and charger to go with it. What's the latest on this, which D cells are the best for me to order, obviously I was going to order the AccuEvolution ones originally but not after reading this, but am none the wiser as to which ones to go for instead?

Also, any recommendations for a charger, cost is not an issue?


EDIT

I’ve done a little bit more research and wanted to know if Ansmann are any good and if anyone has had any experience with them, good or bad:-

These are their 10,000mAh batteries http://www.ansmann.de/cms/en/consum...hargeable-batteries-nimh/mono-d/10000mah.html

And this is their battery management charger http://www.ansmann.de/cms/en/consumroot/chargers-and-power-supplies/xc3000.html

Thanks.


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## Nadrek (Nov 6, 2011)

I bought four AccuEvolution D LSD's a month or so ago, and charged them on my Maha-808M immediately after. My CBA III, set for a 10A discharge rate, reports the cell almost immediately drops to 1.03V, and only discharged 7.18AH until the 0.9V cutoff voltage was reached. Needless to say, I'm unimpressed; what is the best way of contacting AccuEvolution? I'll be checking the other 3 AccuEvolution cells, as well as some older CTA 12AH and much older GI 8AH stadard NiMH cells, all charged within a few days of each other (a month ago).


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## jasonck08 (Nov 6, 2011)

Nadrek said:


> I bought four AccuEvolution D LSD's a month or so ago, and charged them on my Maha-808M immediately after. My CBA III, set for a 10A discharge rate, reports the cell almost immediately drops to 1.03V, and only discharged 7.18AH until the 0.9V cutoff voltage was reached. Needless to say, I'm unimpressed; what is the best way of contacting AccuEvolution? I'll be checking the other 3 AccuEvolution cells, as well as some older CTA 12AH and much older GI 8AH stadard NiMH cells, all charged within a few days of each other (a month ago).



Have you considered voltage drop across the wires of your discharging setup? I know with my CBA and even just the short 4" 10AWG wires, resistance is high (i think because of the poor plug connection). Resistance in the wires can cause a significant voltage drop at a 10A discharge... Secondly, cells are not rated at a 1C discharge, but at a 0.2C. Try that and see what the Ah is.


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## 357mag1 (Nov 6, 2011)

Nadrek,

Your testing exactly matches my use in high current flashlights. The original AccuEvolution cells were some of the best, now they are just about the worse rechargeable D cells on the market. They have terrible voltage sag even under a 2amp load.


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## fnsooner (Nov 6, 2011)

I have been testing ten of my D nimh batteries. Three are the old style AccuEvolutions, three the new style, and two Tenergy Premiums.

TP = Tenergy Premium 10000mAh non-LSD purchased 08/11
OS = Old style AccuEvolutions 10000mAh purchased 01/10 
NS = New style AccuEvolutions 10000mAh purchased 07/10 

Here is a link to a comparison pic of new vs old. http://www.candlepowerforums.com/vb...uality-gone!&p=3608273&highlight=#post3608273


I used the Maha C808M eight bay charger and the Accucel 8150 hobby charger to test the cells.

I prepared all the batteries for testing by putting them through a conditioning cycle on the Maha. Throughout the rest of the testing I recharged and kept the cells topped off by using the default charging on the Maha.

I used the 8150 hobby charger to discharge the batteries to .9V. All tests used the same type of connection to the battery, rare earth neodymium magnets.


Here are the capacity(mAh) numbers with the cells under a load-


1A2A3A4ATP-11032696277898666TP-21023396147889549OS-1958090127305510OS-2935686767399708OS-3927388367610726NS-195998904320171NS-295718802477621NS-395298773280018




I also tested these cells in my TK70. I ran the TK70 in turbo until the step-down to high occured.
TP = 85 minutes
OS= 76 minutes
NS = 61 minutes


I am going to put the eight test batteries on a shelf and do a 3, 6 and 12 month 1A discharge test to check their LSD capabilities. 


I have twenty of the old style AccuEvolutions and I think I will find my best eight and assign them to my TK70. I have ten of the new style(a hundred bucks worth of subpar cells). Oh well, I have enough low power things to use them on. 


From every thing I have seen, there appears to have been a "bait and switch" perpetrated here.

Thanks 357mag1 for noticing this problem. As was documented earlier in this thread, I was mixing the new style AccuEvolutions with the old style in my maglite. I am not sure if that is dangerous, but it's probably not a good idea.


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## KiwiMark (Nov 8, 2011)

fnsooner said:


> Here are the capacity(mAh) numbers with the cells under a load-
> 
> 
> 1A2A3A4ATP-11032696277898666TP-21023396147889549OS-1958090127305510OS-2935686767399708OS-3927388367610726NS-195998904320171NS-295718802477621NS-395298773280018



It doesn't look too bad . . . up to 2A anyway. The OS batteries and the Tenergy ones are OK up to 3A, but they all suck at 4A. This is useful info but as far as LSD characteristics go I really look forward to your testing to see if the new cells are really LSD or not.


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## 45/70 (Nov 8, 2011)

Just for comparison, I thought I'd upload this CBA plot of 4 Powerizer 10Ah D cells from a few months ago. These are conventional NiMh cells (non LSD) and it is important to note that these cells are *about 6 years old*. I don't have an accurate cycle count, but estimate probably between 25 and 50 cycles.


The cells were charged (4 in series) on an iCharger 106B+ at 3A (maximum recommended rate, for these particular cells, ie. 0.3C). For the 2A discharge test, the cells were rested after charge completion, for 24hrs in each case. The 3A test was done after a rest period of 96hrs. Also, because these cells were discharged in series, the cutoff voltage was set to 1.00 Volt/cell (4.00 Volts). The resulting capacity of the "pack" was 7386mAh for the 3A test, and 8071/8072mAh for the two 2A tests.

I did not test these cells at higher rates of discharge, as 3A is the maximum required for my application (4D [email protected] SSC P7). Also there is an irregularity in the 3A discharge about 60% through the test. The setup apparently was bumped, or something, as there is a voltage drop at this point. I imagine it is rather insignificant, but the resulting capacity may have been ever so slightly higher, if this had not occurred.

These cells are showing some signs of age related voltage depression, as can be seen in the discharge plots. As I mentioned earlier in this thread, I was considering replacing these cells with AccuEvolutions, but am still undecided. For now anyway, the Powerizers are still holding up reasonably well. This is especially true when comparing these 6 year old cells to the discharge data of the AccuEvolution cells presented above. All I can say is, hummm.:thinking:

The plots,









Dave


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## jasonck08 (Nov 8, 2011)

KiwiMark said:


> It doesn't look too bad . . . up to 2A anyway. The OS batteries and the Tenergy ones are OK up to 3A, but they all suck at 4A. This is useful info but as far as LSD characteristics go I really look forward to your testing to see if the new cells are really LSD or not.



I can pretty much guarantee that its resistance in his discharging setup that is causing such pathetic numbers @ 4A for all cells. The charger is set to stop discharging at 0.9v, when in reality it may be cutting off at 1v or more due to the wires resistance.


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## Battery Guy (Nov 8, 2011)

fnsooner said:


> Here are the capacity(mAh) numbers with the cells under a load-
> 
> 
> 1A2A3A4ATP-11032696277898666TP-21023396147889549OS-1958090127305510OS-2935686767399708OS-3927388367610726NS-195998904320171NS-295718802477621NS-395298773280018



Good grief, those numbers are terrible! I haven't tested an D-NiMH cells, but ALL of the AA-NiMH cells that I have tested perform better at 4 A than these cells do. Are you sure those numbers are correct? I would expect these cells to at least be able to deliver decent discharge at 1C.


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## fnsooner (Nov 9, 2011)

jasonck08 said:


> I can pretty much guarantee that its resistance in his discharging setup that is causing such pathetic numbers @ 4A for all cells. The charger is set to stop discharging at 0.9v, when in reality it may be cutting off at 1v or more due to the wires resistance.





Battery Guy said:


> Good grief, those numbers are terrible! I haven't tested an D-NiMH cells, but ALL of the AA-NiMH cells that I have tested perform better at 4 A than these cells do. Are you sure those numbers are correct? I would expect these cells to at least be able to deliver decent discharge at 1C.



Thanks for looking at those numbers guys. I suspect the same thing that you guys do, voltage drop at connection or wires when doing the 4A tests. That is one of the reasons I put my connection type in the test.

There are tests around here about everything you can think of except you can't find very good comprehensive testing of D cells. So I figured what the heck, I'll test them myself.


When I first got my hobby charger(3 or 4 months ago), I used a battery holder with pos and neg leads that I purchased at Radio Shack. My results looked good at the 1A discharge test, but even at 2A the results started looking dubious. I even used a clamp to put pressure at the neg and pos posts of the battery holder.

It wasn't until I started using magnets that my results started making sense. That is until I got to the 4A tests. I suspected that I might be getting some resistance in my connections using the magnets with the 4A discharge, but I wasn't sure what a good D cell should read at 4A.

I may start looking for a better way to connect my batteries to my hobby charger for the 4A+ tests. Any recommendation?




But at the end of the day, this is a comparison of these eight cells against each other. The results along with TK70 results, and others noticing bad performances of these cells, point towards the NS AccuEvolutions not being up to snuff. IMO


I have no problem saying I messed up as I am after the truth and will post any other tests or conclusions as they come.


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## Nadrek (Nov 9, 2011)

jasonck08 said:


> Have you considered voltage drop across the wires of your discharging setup? I know with my CBA and even just the short 4" 10AWG wires, resistance is high (i think because of the poor plug connection). Resistance in the wires can cause a significant voltage drop at a 10A discharge... Secondly, cells are not rated at a 1C discharge, but at a 0.2C. Try that and see what the Ah is.



I lost a long post, but the long and short of it:

My previous test was flawed - rotating the battery in the holder makes a significant voltage difference; I'll be retesting with a dose of DeoxIT and the rotation.

As far as voltage drop, despite the Cambion (http://www.newark.com/jsp/search/browse.jsp?N=0&Ntk=gensearch_001&Ntt=categorynumber4717) battery holder being soldered to 3" of 12ga or 14ga wire with a crimped 45A Powerpole on the end, plugged directly into the CBA III, a 12A test showed 1.153V at the battery terminals (measured on a Fluke 179), and 1.03V from the CBA III. 

New tests will be at 0.5C, with a 0.85V cutoff, after a brief wipe with DeoxIT and some rotation in the battery holder, as a reasonable balance.


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## fnsooner (Nov 20, 2011)

Ok, I have been attempting to address the resistance problem when I am discharging at 3A and above. Trial and error has led me to using some 10 guage wire and 10 guage banana plugs I purchased at Radio Shack. I am also using 10 guage high temp ring terminals and magnets. 










So all my discharge tests in this post are using the above method. I will only do 4A and 5A tests this time around, except for the two Tenergy Centura LSD 8000mAh cells I received since I posted last. I tested the Centuras at 1,4,5A and did a 1A discharge fresh out of the package.


TP = Tenergy Premium 10000mAh non-LSD purchased 08/2011
OS = Old style AccuEvolutions 10000mAh purchased 01/2010 
NS = New style AccuEvolutions 10000mAh purchased 07/2010 
TC = Tenergy Centura LSD 8000mAh purchased 11/2011


4A5A1A1A out of the boxTP-191857458TP-290067374OS-180386641OS-284956587OS-382916235NS-17243758NS-268492140NS-35220734TC-18026612887802020TC-28356676686702018






I tested the Tenergy Centuras in my Fenix TK70 just like I did the others. Here are the results of all the cells. Run time on turbo before it steps down to high.
TP = 85 minutes
OS= 76 minutes
NS = 61 minutes
TC = 74 minutes




During the entire testing that I did, I always had trouble with the new style AccuEvolutions first as I increased my amperages in my tests. They were like the canary in the mine shaft. If there was a resistance threat, they always puked first. 


All in all, this little project got me some reps on my new hobby charger and I can now assign my cells accordingly. 
Here is a picture of some stuff I tried to discharge with but didn't make the cut. 







I will use the Accucel-8150 with the supplied leads and clips for anything under 2A and the 10 guage leads with magnets up to 5A. I really can't see me needing to use this hobby charger very much, just every once in a while to test something.

Getting back to the old style AccuEvolution vs the new style. I think that there is definitely a difference between the old style and new style that I own and that the new style is definitely inferior. Having said that, my most taxing D powered device is my TK70 which the new style AEs power perfectly fine minus some runtime. The new style can do 2A with no problem and that is 90% of what I use them for. 

My biggest disapointment is that I was mixing old style with new style. Maybe this isn't a big deal. Duracell makes the white top(Duraloop) and the black top. I am sure they get mixed and matched with no adverse affect. 

To tell you the truth, I was happy as a clam with my AccuEvolution Ds, old and new style, before I read this thread. I was just getting into Li-ons and I was just charging and using my D nimhs as needed. In real world use, I could not tell any difference in performance. Of course I was not using any high amp devices. 

Now to put the test subjects back on the shelf for some LSD tests.


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## Mr Happy (Nov 20, 2011)

fnsooner said:


> Ok, I have been attempting to address the resistance problem when I am discharging at 3A and above. Trial and error has led me to using some 10 guage wire and 10 guage banana plugs I purchased at Radio Shack. I am also using 10 guage high temp ring terminals and magnets.


Wouldn't it be better to place the magnet on the outside when attaching the ring terminals to the battery, rather than sandwiched in the middle? Otherwise the current has to flow through the magnet and this inserts an extra contact point and extra resistance into the circuit.


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## fnsooner (Nov 20, 2011)

Mr Happy said:


> Wouldn't it be better to place the magnet on the outside when attaching the ring terminals to the battery, rather than sandwiched in the middle? Otherwise the current has to flow through the magnet and this inserts an extra contact point and extra resistance into the circuit.



Now you tell me.

Seriously though, I tried it that way and I was getting less consistent results. This is my first real go at using a hobby charger and these tests are going to be the extreme that I use it for. I am happy with the results using the magnets.


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## 357mag1 (Nov 20, 2011)

fnsooner,

Your results mirror my own though your testing was much more thorough. 

Compare the current draw on the TK70 and you will see due to voltage sag the new style AccuEvolutions draw almost an amp more to get the same brightness. That is the reason for the reduced runtime.

I have also mentioned if people used the new style batteries in LED regulated lights they would not see much difference just reduced runtime.

One application where I noticed the difference was in my Lambda lights where the new style sent over 2amps less current to the LED making it much dimmer.

The other was my 6 cell Maglite running the high ROP. It was awesome with the old cells and looked pitiful with the new (dim). That was what lead me to testing and this thread.

I have tested most of the new LSD D cells out there and the Tenergy Centura are the only ones I've found worth purchasing. It doesn't hurt that they are cheaper than the AccuEvolution and all the others.


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## fnsooner (Nov 22, 2011)

357mag1 said:


> I have tested most of the new LSD D cells out there and the Tenergy Centura are the only ones I've found worth purchasing. It doesn't hurt that they are cheaper than the AccuEvolution and all the others.



I agree, If I had to buy any cells today, it would be the Tenergy Centuras.


We'll see how things go in the LSD test. I thought since I had all my stuff out, I would charge all my D cells. The cells that were in camping stuff that I won't use until next spring were put on the shelf with the original test batteries. So I should have enough cells at the three and six month mark to get a good feel for their LSD capabilities. Four of the old style AEs will be stored in my pickup as spares for my TK70. Of course the need to use these cells trumps the test.


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## Battery Guy (Nov 22, 2011)

Mr Happy said:


> Wouldn't it be better to place the magnet on the outside when attaching the ring terminals to the battery, rather than sandwiched in the middle? Otherwise the current has to flow through the magnet and this inserts an extra contact point and extra resistance into the circuit.





fnsooner said:


> Now you tell me.
> 
> Seriously though, I tried it that way and I was getting less consistent results. This is my first real go at using a hobby charger and these tests are going to be the extreme that I use it for. I am happy with the results using the magnets.



My guess is that you traded a fluctuating low contact resistance with a stable high contact resistance.

It is a damn shame that they don't make these chargers with separate voltage sense leads. That would solve all of these problems.


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## mcmc (Nov 22, 2011)

Thanks all you guys for some informative testing and reporting of your user experiences! I was in the market for a small batch of nimh D cells, and I was going to buy the Accuevolutions, but thanks to this thread, bought a set of Centuras and even saved a little skrill.

I was originally put off by the 2000 mah capacity difference, but it seems like this may not have been a real factor, kind of like varying definitions of "lumens output" between different manufacturers.

The Centuras are running great so far.

Side note, my old Tenergy's, the 10,000 mah blue ones without LSD, are still running decently. I've charged them many a time over their 5+ year run, but they still maintain a good charge. My quad cree runs a little brighter on the Centuras but the Tenergy's will still have decent life left as backups I think. And though I sometimes let the quadcree mag sit for several weeks without use, truthfully I never really experienced a sense of "oh I wish had lsd" - ie, there was always juice enough when I needed.

So, lsd capability may not be *all* that necessary for everyone, even flashaholics like us. I truthfully got the Centuras out of fun and to test it out, not so much out of experienced need  so the original Tenergies may still be a viable option for those out ther wanting something more affordable.


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## fnsooner (Nov 23, 2011)

Battery Guy said:


> My guess is that you traded a fluctuating low contact resistance with a stable high contact resistance.
> 
> It is a damn shame that they don't make these chargers with separate voltage sense leads. That would solve all of these problems.



What are separated voltage sense leads?

I actually see where you and Mr, Happy are coming from. I think my numbers show that there is resistance affecting the numbers and if I were to take this to another step, I would need to address this. I would probably start with tweeking that contraption that I made out of a sliced and diced maglite.


At one point I was thinking about starting a new thread and collecting all my data for some sort of D round-up. After fighting this resistance problem, I decided to keep it here and relevant to the topic of this thread. Treat all the cells exactly the same and compare the numbers.
I don't know what the math is that would explain why the new style AccuEvolutions are affected more by the resistance than the other cells, but I do think it is relevant. Maybe it is the resistance of my leads and connectors plus the internal resistance of the cells.


But me, I am just an old broken down service tech trying to test a few batteries. Actually, I am kind of lazy and would have prefered that somebody else tested these cells. 


I have been lurking these boards for a few years and when people like you and Mr. Happy talk, I listen and try to learn. I do appreciate legitimate constructive criticism that has been offered, but at this point, the tests are over and the batteries are on the shelf. I am tired of looking at these cells and they have started the LSD testing. I am to the point where my Missouri neighbors can relate, "SHOW ME". Show me a link or a picture where someone difinitively proves a better way. The trial and error is over for me. At least for three months. 


I have done quite a bit of googling and can't find where anyone has done a D nimh battery test above 3a that is relative today. I have come to the conclusion that if this was easy that there would be comparative tests, using a hobby charger, all over the place. And when I can find some sort of testing, they don't divulge the way they connect the hobby charger to the batteries.


If someone can provide a link to a better comparison of D cells at higher amp draws, I will reference it until something better comes along. Until then...


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## 45/70 (Nov 23, 2011)

mcmc said:


> Side note, my old Tenergy's, the 10,000 mah blue ones without LSD, are still running decently......
> 
> So, lsd capability may not be *all* that necessary for everyone, even flashaholics like us.



I forget exactly why, as it's been a while, but sometime ago I determined that the Tenergy and Powerizer 10Ah "D" cells likely come from the same source. I also agree that there is little difference in self discharge between LSD NiMh "D" cells vs. traditional NiMh "D" cells. In larger cell sizes, self discharge seems to be much less of a problem. I've left my Powerizer cells for months, and they still retained a decent amount of charge.



Battery Guy said:


> It is a damn shame that they don't make these chargers with separate voltage sense leads. That would solve all of these problems.



I'm all for precision and accuracy when it comes to about anything, but is it really necessary to have independent voltage sensing when doing this type of testing on an amateur level? I could understand needing a setup like this if one were writing a white paper for a manufacturer, or something. It seems to me though that provided any potential resistance problems regarding the hookup of the cell(s) are worked out to an acceptable level, that separate voltage reading really wouldn't be necessary for comparative purposes. Provided the test conditions are the same, if the testing of cell "A" results in a higher capacity than cell "B", it seems to me that cell "A" is the higher capacity cell, regardless of what independent voltage sensing may reveal. Am I missing something here, or what?:thinking:

Dave


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## SilverFox (Nov 23, 2011)

Hello Dave,

Never let it be said that a rational argument is capable of standing in the way of the OCD tendencies of those afflicted with battery mania...  

Tom


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## SilverFox (Nov 23, 2011)

Hello Dave,

Never let it be said that a rational argument is capable of standing in the way of the OCD tendencies of those afflicted with battery mania...  

Tom


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## 45/70 (Nov 23, 2011)

SilverFox said:


> Never let it be said that a rational argument is capable of standing in the way of the OCD tendencies of those afflicted with battery mania...



Ya, well, I agree with that suggestion, as I suffer from the affliction myself, obviously. I just wondered if I was missing something.:shrug:

Dave


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## 3Cylinders (Nov 25, 2011)

Is it safe to mix 2 old style AccuEvolutions with 2 new ones in a Fenix TK70? The reason I ask is because I currently have 6 old styles and would like to purchase 2 more to give me 2 sets of 4. Am I OK to mix old and new like this, or should I just order 4 Tenergy Premiums instead and try to find a use for the 2 spare AccuEvolutions? Thank you in advance.


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## Mr Happy (Nov 25, 2011)

3Cylinders said:


> Is it safe to mix 2 old style AccuEvolutions with 2 new ones in a Fenix TK70? The reason I ask is because I currently have 6 old styles and would like to purchase 2 more to give me 2 sets of 4. Am I OK to mix old and new like this, or should I just order 4 Tenergy Premiums instead and try to find a use for the 2 spare AccuEvolutions? Thank you in advance.


Never mix different batteries in the same device at the same time. Never mix old and new batteries. It's something you should learn as soon as you are old enough to talk and should remember for every year following.


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## 357mag1 (Nov 25, 2011)

3Cylinders said:


> Is it safe to mix 2 old style AccuEvolutions with 2 new ones in a Fenix TK70? The reason I ask is because I currently have 6 old styles and would like to purchase 2 more to give me 2 sets of 4. Am I OK to mix old and new like this, or should I just order 4 Tenergy Premiums instead and try to find a use for the 2 spare AccuEvolutions? Thank you in advance.



I sure wouldn't. I can't imagine batteries being less suited to mix. Cycle the old ones through the light and get 4 new Tenergy batteries. Either their standard 10,000mah version or the 8000mah LSD.


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## 3Cylinders (Nov 26, 2011)

So, just to be clear, the old style batteries have not been used at all, they are just the old style with (apparently, according to this thread) better performance than the new ones. I was wanting to mix old style new and unused AccuE 10,000mah with new style, new and unused AccuE 10,000mah. I understand I shouldn't mix used batteries with unused ones. I read in another thread that it's best to use the same brand batteries with the same labeled rating. Now I'm being told that I shouldn't in this case. Is it because of the age? I could easily see ordering 4 batteries from a distributor and getting 2 batteries that are 2 years old and 2 that were manufactured last week.


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## My2Cents (Nov 26, 2011)

Unlike eneloops, there is no lot number or production date on these batteries so I don't think one can be certain when they were manufactured. It is possible that these were on same batch but 2nd set has been sitting on the shelves for, say, 2 years.


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## Mr Happy (Nov 26, 2011)

3Cylinders said:


> So, just to be clear, the old style batteries have not been used at all, they are just the old style with (apparently, according to this thread) better performance than the new ones. I was wanting to mix old style new and unused AccuE 10,000mah with new style, new and unused AccuE 10,000mah. I understand I shouldn't mix used batteries with unused ones. I read in another thread that it's best to use the same brand batteries with the same labeled rating. Now I'm being told that I shouldn't in this case. Is it because of the age? I could easily see ordering 4 batteries from a distributor and getting 2 batteries that are 2 years old and 2 that were manufactured last week.


When you use cells together you want them to be as close to identical as possible. In this case we know from tests people have done that the old style and the new style cells perform differently. Since we know they are not the same it would be unwise to mix them together. Test results are always more important than labels.

If you buy four batteries from a distributor you would normally expect them to come from the same batch off the same production line. Even so, the dedicated people on the forum will buy six or eight batteries and test them all to find four that make a good match. You don't have to be that dedicated, but for the absolute best performance it pays off.

What happens if you mix unlike or mismatched cells together is that usually lower performing cell or cells will degrade faster than the others with each use, eventually becoming the weak link in the pack. It will end up looking like the whole pack is performing badly, when in fact it is only one or two cells letting the side down. If you match the cells together carefully this is less likely to happen.


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## fnsooner (Nov 26, 2011)

There are two things that make the new style and the old style different. The positive button has changed and the recipe for the Nimh part of the battery is different. It is hard to say whether these changes happened at the same time, but my guess is probably so. 

IMO, using these two batteries together is no different than going to Wally World and grabbing a pack of Rayovac LSDs and a pack of Duraloops and using them together. It is up to you whether this is a good idea. 

Another thing I noticed concerning new versus old, AccuEvolution reps have had a history of showing up on these forums to discuss their products. They have been suspicioiusly quiet and I suspect that they would of liked this thread to wither on the vine.


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## 3Cylinders (Nov 26, 2011)

Very good information. Thank you. Now to figure out what to do with 2 unused batteries.


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## Nubo (Dec 20, 2011)

The dozen cells I bought in March have no apparent LSD properties. This has been demonstrated by their use in rarely-used flashlights and in a soap dispenser where they should have lasted for many months. After about a month they are flat regardless of use. Sadly, this is very different from the set of cells I bought a couple of years back, which still perform great and hold charge very well.

So Accu is charging premium price for an imaginary feature. Rather disappointed that there is no action apparent on their part. I can only surmise that either they don't do any quality testing or that they are simply happy to continue selling crap to people who are buying off of previous quality, reputation, or simply false product claims. They have gone from extraordinary quality to bargain-bin quality but still charging the premium price. Very disappointing.

I do so wish that Sanyo would make Eneloops in all standard consumer sizes.


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## 357mag1 (Dec 20, 2011)

I agree AccuEvolution keeps charging a Premium for cells that my testing indicates are about the poorest performing Nimh D cells on the market.

AccuEvolution appears to have no interest in the poor performance of their cells and I can only assume they are content to milk all the profit possible off their previous reputation.

I've found the Tenergy LSD cells (Centura) to be quite good. Better than any of the other more expensive LSD D cells on the market though still not quite up to the performance of my original 6 AccuEvolution cells.


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## fnsooner (Feb 11, 2012)

Well, it has been three months. Time to pull four of the test sujects off the shelf and do a little LSD testing. 

I discharged them on my Accucell 8150 with 10 guage leads and magnets at 1A rate to .9VDC. When I finished testing the cells, I charged them on my Maha C808M on the default settings and then did another discharge test to check their capacity after charging. I also put the percentage of charge left compared to fully charged cell.

TP = Tenergy Premium 10000mAh non-LSD purchased 08/2011
OS = Old style AccuEvolutions 10000mAh purchased 01/2010 
NS = New style AccuEvolutions 10000mAh purchased 07/2010 
TC = Tenergy Centura LSD 8000mAh purchased 11/2011


3 Mo. LSDFully ChargedTP-182051022980%TC-17894862091%OS-18419940789%NS-18644973388%







Remember, this is just a Low Self Discharge test. As proven throughout this thread, when the current is increased the newer style AccuEvolutions fall on their face and I wouldn't purchase them.

See you in three months and I'll do a six month LSD test on four more cells. :wave:


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## 357mag1 (Feb 11, 2012)

fnsooner said:


> Well, it has been three months. Time to pull four of the test sujects off the shelf and do a little LSD testing.
> 
> I discharged them on my Accucell 8150 with 10 guage leads and magnets at 1A rate to .9VDC. When I finished testing the cells, I charged them on my Maha C808M on the default settings and then did another discharge test to check their capacity after charging. I also put the percentage of charge left compared to fully charged cell.
> 
> ...



Good info and very consistent with what I'm finding.

Can't agree with buying the "New" AccuEvolutions for any reason unless you find them very cheap. Remember those mah readings are misleading. If the chargers read output in Watt Hours we would see the lower voltage of the AccuEvolution cells would make them the lowest output of the bunch even at lower current readings.

In any regulated light the higher voltage of the Tenergy cells will cause a lower amperage draw from the cell. For example I have a Mag LED build that draws 2.5amps with Tenergy cells fresh off the charger, the same light draws just over 3amps using the AccuEvolution cells. If that draw stayed constant my 10,000mah Tenergy cells would last 4 hours. The AccuEvolution cells would need 12,000mah just to come close.

Hope that makes sense.


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## fnsooner (Feb 12, 2012)

Yes, that makes sense. I have seen fellow member 2100 discuss this where weak or depleted cells actually cause some flashlights to draw more amperage trying to maintain a certain output.

When I looked at the numbers, I thought, well that looks prety decent if you use the new style AccuEvolutions in low drain devices. 

I am now in total agreement with you. I see no reason to ever buy the AccuEvolution D cells. There are better AND cheaper alternatives. I like LSD cells, so my personal choice would be the Tenergy Centuras if I ever need to buy more.



One other thing I have been meaning to mention. When I first started testing my cells, I had never used a hobby charger and other than my La-Crosse bc-9009, I have never done much nimh analyzing. So when I first got started, I wasn't real sure how I was going to analyse these cells.

Early on, I kept having trouble with missed termination while charging with my Accucell 8150 and my AccuManager 20 charger. I eventually turned all charging duties over to the Maha C808M and have never had a missed termination in the hundreds of hours of charging any of these D cells. The Maha has been one of the best investments I have made since starting this battery/flashlight hobby.


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## chewy78 (Feb 12, 2012)

Not to hijack but if you want good some cheap d nimh 10,000mah cells, go to the good deals section in the market place. There's a link to ebay for some 8 new in wrapper tenergy d cells that are going for $24.99. or 4 for $14.99. 
Good bang for the buck .


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## chewy78 (Feb 12, 2012)

double post, this forum is slow


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## 357mag1 (Feb 12, 2012)

I don't trust my AccuCell 8150 to properly terminate a single Nimh cell during the charge phase. It seems to work fine on tool batteries with multiple cells. My Triton 2 EQ doesn't seem to have any termination problem with singel cells.

I just bought the Maha C808M from Thomas Distributing. It should be here soon. Hopefully my experience will mirror yours with the 808.


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## Bludger (Mar 15, 2012)

fnsooner said:


> Well, it has been three months. Time to pull four of the test sujects off the shelf and do a little LSD testing.
> 
> <snip>
> See you in three months and I'll do a six month LSD test on four more cells. :wave:



Thanks for your data mate, it certainly has made my choice in D cells easier, especially since I need to get them shipped from the US to Australia, which makes mistakes even more expensive.

I have a hyperion EOS606i ac/dc hobby charger here that I'm going to mod to match your Turnigy....your thread is just overflowing with great info!


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## fastgun (Jun 29, 2012)

So after 3 months on the shelf...would not the Tenergy Premium non LSD be stronger than the Ternergy Centura?


I need some batteries next week and they need to be a longer term type that would be recharged every 3-4 months.
From the above test, I think that I should get the Tenergy Premium.

Is this a correct understnading of the above test?


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## celler (Sep 30, 2012)

It not only appears that the quality may be gone, but AccuEvolution may be gone from the market period. I do not see them at Thomas Distributing anymore and they seem to be scarce elsewhere on the net. An email to the corporate website went unanswered. So much for having a higher mah LSD battery in D size around.


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## snakebite (Oct 1, 2012)

i just dumped 16 of these in the recycle bin.high resistance.going below .9 volt at 1 amp load.a neighbor bought these last year for his deer feeders.big waste of money!
i did cycle them without any improvement.junk!!!!
btw these worked poorly for the first few cycles but then the feeder would reset when it tried to dispense.it worked fine on my old 8ah panasonics.from 1998!


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## 357mag1 (Oct 1, 2012)

fastgun said:


> So after 3 months on the shelf...would not the Tenergy Premium non LSD be stronger than the Ternergy Centura?
> 
> 
> I need some batteries next week and they need to be a longer term type that would be recharged every 3-4 months.
> ...



I have not been on this site in quite some time. My response is probably too late to do you any good but yes the Premiums I've tested have more left after 3 months than the Centuras. Both are the best D cells I've tested.

Don't mourn the loss of the AccuEvolutions. Even the original cells which I have didn't reach 10,000mah capacity. Those original cells were great cells but had no more capacity than the Centuras from my extensive testing. They did hold a higher resting/static voltage than the Centuras but under a heavy load they didn't maintain the higher voltage. The Centuras will do anything the original cells would do.


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## fnsooner (May 18, 2013)

Hey all, I am reviving this thread to give some results of my LSD testing on a few different D Nimhs. I missed my six month and one year mark to test the batteries, but they sat patiently on a shelf waiting for 18 months. 


All batteries listed below were fully charged on my Maha C808M during November of 2011.


During May of 2013, I discharged them on my Accucell 8150 with 10 gauge leads and magnets at 1A rate to .9VDC. When I finished testing the cells, I charged them on my Maha C808M on the default settings and then did another discharge test to check their capacity after charging. I also put the percentage of charge left compared to fully charged cell.

I am LSD testing eight batteries. Two samples of each listed below.


TP = Tenergy Premium 10000mAh non-LSD purchased 08/2011
TC = Tenergy Centura LSD 8000mAh purchased 11/2011 
OS = Old style AccuEvolutions 10000mAh purchased 01/2010 
NS = New style AccuEvolutions 10000mAh purchased 07/2010


Battery18 mo LSDFully ChargedTP-231501003031%TP-34905981950%TC-27668863488%TC-37625871487%OS-27158909678%OS-37066892279%NS-24263969743%NS-35799957660%


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## fnsooner (May 18, 2013)

Bludger said:


> Thanks for your data mate, it certainly has made my choice in D cells easier, especially since I need to get them shipped from the US to Australia, which makes mistakes even more expensive.
> 
> I have a hyperion EOS606i ac/dc hobby charger here that I'm going to mod to match your Turnigy....your thread is just overflowing with great info!



You're welcome.


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## 357mag1 (May 18, 2013)

I've never let them set on the shelf that long but your test just confirm what I have been saying about the AccuEvolution cells. Even the original cells are no better than the Tenergy Centura cells. The Centura's even handle the high (in excess of 14amps) current draws better than my original AccuEvolution cells. 

Feel free to buy the AccuEvolution cells but you we be paying more money for lesser cells. In fact my testing leads me to believe they are the worst rechargeable NIMH D cells on the market.


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## fnsooner (May 20, 2013)

I agree 357mag1, the new style Accuevolutions are crap. I have ten of them. 


Once I finished my tests, I wanted to keep the NSs where I could keep an eye on them in a group. I put nine of them in three Rayovac Sportsman LED lanterns. Ironically, these are by far the most used D powered devices I own. I use the lanterns in a couple of dark closets and a kitchen pantry. They get used all the time.


From the info in this thread, I wish all my 38 D cells were the Tenergy Centuras. I pick the Centuras over the Premiums for the same reason most people pick Eneeloops over non-LSD AAs. 


Thanks for starting this thread 357mag1. I hope it has caused Accuevolution some grief and kept people from buying inferior batteries.


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## 357mag1 (May 20, 2013)

I started the thread in hopes to help others from wasting their money on the New AccuEvolution cells. Guys like you have helped confirm the cells are actually garbage and it isn't just one unhappy customer. Maybe together we saved some poor soul with limited resources from purchasing the poor quality AccuEvolution cells. 

I would settle for a return of the original cells but now that I know the Tenergy Centura's are better than even those cells and cheaper it really doesn't matter. Those of us using D NIMH cells have a great quality low discharge cell at a very reasonable price.

Thanks for the kind words.


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## D2000 (May 31, 2013)

Once again a productive thread. Count me as the first saved soul. About to buy some of the Tenergy's right now.


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## StorminMatt (Jun 1, 2013)

fnsooner said:


> From the info in this thread, I wish all my 38 D cells were the Tenergy Centuras. I pick the Centuras over the Premiums for the same reason most people pick Eneeloops over non-LSD.




I have quite a few Centura C and D cells. And I have to admit that they have been REALLY good to me. However, I also would like to have some Premiums for certain occasions. According to the tests in this thread, from the standpoint of capacity, the Premiums are still ahead of the Centuras at the three month point. This means that the Premiums not only hold an advantage over Centuras for immediate use. But they hold at least SOME advantage all the way up to a little more than three months. So Premiums would DEFINITELY be better in situations where capacity is of utmost importance and I don't need to worry about whether the batteries are still ready to go after several months.


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## Mr Floppy (Jun 2, 2013)

StorminMatt said:


> So Premiums would DEFINITELY be better in situations where capacity is of utmost importance and I don't need to worry about whether the batteries are still ready to go after several months.



Premiums would definitely be better if you start cranking up the amps over 3A too.


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## StorminMatt (Jun 3, 2013)

Mr Floppy said:


> Premiums would definitely be better if you start cranking up the amps over 3A too.



I've not found the Centuras to be weaklings at high current draw. They seem to do quite well with my ROP light. In fact, they don't even get warm.


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## The_Driver (Jun 3, 2013)

I used the "C"-size Centuras at 13-17A and they worked great


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## 357mag1 (Jun 3, 2013)

The Premiums are definitely the way to go for Max capacity. In fact unless you plan to let your batteries set for over three months before use the Premiums are the way to go. I like to use Centuras in my camping lanterns which use 8 D cell batteries as they do tend to set a while between uses and I want them ready to go when I grab them.


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## Mr Floppy (Jun 3, 2013)

StorminMatt said:


> I've not found the Centuras to be weaklings at high current draw. They seem to do quite well with my ROP light. In fact, they don't even get warm.



More that the high currents reduces the runtime and the Premiums make up for that.


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## StorminMatt (Jun 3, 2013)

Good point. Speaking of that, I'm actually wondering whether LSD batteries are really as desirable as people around here say. I mean, three months is a LONG time. And I'm willing to bet that most folks here will probably charge their batteries LONG before that time passes - especially in EDC or work lights. When it all comes down, the extra capacity of non-LSD lights would seem to win out over having a battery that is able to hold 85% of its charge after a year (or, as these tests indicate, 87-88% after 18 months). So why is LSD considered THE way to go (and non-LSD something to avoid like the plague)?


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## Power Me Up (Jun 3, 2013)

LSD cells tend to be more robust - meaning that standard cells may start off with reasonable self discharge rates, but after a bit of use, they may end up with self discharge rates that are a significant problem.


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## 357mag1 (Jun 4, 2013)

Power Me Up said:


> LSD cells tend to be more robust - meaning that standard cells may start off with reasonable self discharge rates, but after a bit of use, they may end up with self discharge rates that are a significant problem.



I thought I was answering the post by StorminMatt when I stated:

I have to agree, even at 10amp draws the Centura are only edged out by the Premiums. The Centuras out perform the original AccuEvolution cells at high current loads from my testing.

In extended testing at higher current draws the Premium cells usually hold a slight advantage over the Centuras through the entire discharge cycle though by the mid-point that advantage is almost non-existent. 

Eneloop AA LSD cells tend to be more robust than most but are beat out by the Energizer 2300mah cells with the green top. These cells are also made by Sanyo (now Panasonic) and my testing has shown they outperform the Eneloop cells in all respects. If the quality of the cells are identical it appears the standard cell is actually more robust. Plenty of crappy AA cells out there even ones touting LSD qualities.


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## fnsooner (Jun 4, 2013)

I think the whole LSD vs non-LSD argument should be decided by application. I remember when LSDs first came out, it was the camera crowd that had to make a decision. Are they a professional photographer and need max capacity and need to charge their cells frequently or are they an amateur shutterbug that just needs their camera to work when they pick it up?... even if it has been sitting for months.


I fall into the latter camp. I have many things that use D cells, but I don't use any of them much. I just want them to work when I use them. I have many batteries(both Nimh and Li-on) but I don't have many loose batteries. All my batteries are in something and most of them somethings are just glorified battery holders; storing batteries for backup or emergencies or sporatic use of item.


Plus, non-LSDs in AAs have left a bad taste in my mouth from previous experiences. All of the AA non-LSDs have failed me and have been tossed. I have yet to have a LSD AA battery fail or be thrown away. It is definitely security over capacity for me.


I own four of the Tenergy Premiums and will use them as needed when a big job might come along and capacity is king.


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## 357mag1 (Jun 4, 2013)

fnsooner,

For your situation I have to agree the Centuras make more sense. It is nice to know we have quality LSD and standard D cells that are reasonably priced. I'm finding some of my D cells sit more now than they use to and the LSD qualities are hard to ignore. When I pick a light up I want it to work even if it has been setting for more than a year.


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