# The AA NiMH Performance Test Thread



## Battery Guy (Oct 21, 2010)

Greetings Everyone,

I have been doing a lot of performance tests on AA NiMH cells recently and posting the results in various threads. I thought that it might be nice to put these results all in one place and update it as more come in.

I hope that this data set will be a nice complement to the comprehensive and exhaustive testing that Silverfox has performed in his NiMH Shootout.

My purpose here is to provide a bit more detailed test results on the more popular NiMH batteries.

*Test Setup*

All cells are discharged on a Maccor series 4300 battery tester. Nickel tab strips are spot welded to each cell to minimize contact resistance. Unless otherwise noted, cells are discharged to a 0.8 V cut-off. All cells were purchased new and tested within a few weeks of receipt. With the exception of the Elite 1700s and Shnoopaloops, all cells were tested fresh out of the package. The Elite 1700s and Shoopaloops went through one break-in cycle on a Maha C9000 prior to testing. Cells are charged at a 1C rate with a 10 mV -dV cut-off, then allowed to rest for 1 hour prior to discharging.

*Limitations*

One cell is hardly what I would call a statistically significant sample. There is certainly going to be variability in cell performance, so please recognize this limitation. Unfortunately, I do not have the time to repeat this work on multiple samples. Also, this testing does not take into account performance degradation that occurs over time due to aging and cycling (except for the Shnoopaloop constant current tests). These results are what you might expect for new cells. Exactly how the cells degrade will depend on the cell design, manufacturing quality and your use/abuse pattern.

In other words, your mileage may vary.

*Constant Current Discharge Results*

Constant current discharge is very close to what a battery sees in an incan hotwire flashlight. For these types of unregulated lights, you really want to know what the voltage of the cell is under load so that you can match it to the bulb output. I hope that these curves serve to compliment the excellent tests that LuxLuthor performed on incan bulbs, the results of which are posted here. 

Each plot will show the performance of the cell under constant current discharge conditions compared to a "control" cell. The control cell that I have chosen is the "Gen 1" white label Eneloop. The plots for the Eneloop are in black, and the plots for the "cell of interest" are in blue. Each plot will show the curves for 1A to 10A discharge in 1A increments. In addition, I am adding a 0.2C constant current discharge curve to some of the plots. The 0.2C discharge was conducted in accordance with the IEC capacity measurement standard. To keep the plots clean looking, I am not going to label each curve. I think that it is easy enough to figure out which curve is which.

*Constant Power Discharge Results*

Constant power discharge is what your battery experiences in a device that has a voltage regulator. Many LED flashlights use a voltage regulator so that the LED always "sees" the same voltage and current from the battery pack. As the battery pack is drained and the voltage of the pack decreases, the current draw on the pack increases to maintain a constant voltage and current for the LED.

The constant power results are presented in the form of a Ragone plot. If you are not familiar with Ragone plots, read the Intro to Ragone plot thread. Ragone plots are a great way to compare the performance of several batteries under various constant power loads on the same plot.

Most of the cells will be discharged up to 8W. I have taken a few cells above 8W, notably Eneloops, Elite 1700, PowerGenix and Imedion 2400. However, limitations of my test equipment make it difficult to go above 8W, so unless it is specifically requested, expect all future results to go up to 8W.

Here is the Ragone plot for the NiMH cells I have tested so far. I know that technically the PowerGenix cell is not an NiMH type, but it is often used in applications where an NiMH might be used so I thought that I would include it.








Here are the constant current discharge curves.


*Elite 1700:* One break-in cycle was run on a C9000 prior to testing. Please note that these tests were performed on Elite 1700 cells purchased back in June 2010. Testing of more recent Elite 1700 cells has shown that they perform less well at high currents. For a comparison between the new and old Elite 1700 cells, see the end of this thread.








*Energizer 2300* Tested fresh out of the package.








*Shnoopaloops*: One break-in cycle was run on a C9000 prior to testing. These are Duraloops purchased from Shnoop. They are essentially three year old Eneloops. See here for the thread to read more detail.








*"Gen 2" 1500x Eneloop*: Tested fresh out of the package. Please note that this graph does NOT have a 1 amp discharge curve. The curves shown are from 2 amp to 10 amp.







*Imedion 2400*: Tested fresh out of the package.







*Sanyo 2700*: Tested fresh out of the package.






*Sanyo 2500*: Tested fresh out of the package.







*PowerGenix NiZn*: Tested fresh out of the package. Please note that the voltage axis is scaled differently than the other comparisons.






*GP Recyko:* Tested fresh out of the package






*Eneloop XX:* Tested fresh out of the package. A special thanks to CPF member *Dusty* who shipped me cells all the way from Northern Ireland for this testing! :thanks:







*TruCell:* Two of these cells were sent to me by CPF member TurboBB. 







*Rayovac Platinum:* Tested fresh out of the package.







*Tenergy 2300 LSD:* Tested fresh out of the package.







*Elite 2000*: These appear to perform as advertised, but don't hold their voltage quite as well as the original Elite 1700s








*Edit: New January 5, 2011*

I was looking over some of my test data and realized that I could extract some additional information that might be of interest to CPF members. In particular, the total discharge energy (Wh) available as a function of discharge current, the efficiency (percent of total available energy) as a function of discharge current, and the energy loss as heat as a function of discharge current. I have included these plots below for your consideration.

*Discharge Energy (Wh) vs Discharge Current (A)*






*Energy Efficiency (%) vs Discharge Current (A)*






*Energy Loss as Heat (Wh) vs Discharge Current (A):* I think that this is a rather interesting plot. The amount of energy lost in the form of heat will determine how hot a battery will get during discharge. The higher the energy loss, the hotter the battery will get (assuming that all of these cells have similar heat capacities).






Hope you find this useful. If there are other NiMH cells of interest, let me know and I will do my best to test them. However, it is not my intention to do this testing on every available NiMH cell on the market, only the more common ones that are of general interest to the CPF community. 

Cheers,
BG


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## Linger (Oct 21, 2010)

Excellent. I agree with your rational for including the nizn.

New cells makes for a good purchase comparison, but *1 year old / 100 cycled cells* would be a grand shoot-out for use-down-the-road. I understand the challenges with aging cells equally, but want to throw the idea out there in hopes that in a few months maybe someone's got an idea.

Cell recommendation: Eneloop Tones / Gen2 (1500cycle) eneloops. I do not have them to contribute at present (waiting for a deal at Dell.ca) Does any one have some gen2 eneloops to volunteer?


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## Notsure Fire (Oct 22, 2010)

Very nice looking graphs.


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## Battery Guy (Oct 22, 2010)

Linger said:


> New cells makes for a good purchase comparison, but *1 year old / 100 cycled cells* would be a grand shoot-out for use-down-the-road. I understand the challenges with aging cells equally, but want to throw the idea out there in hopes that in a few months maybe someone's got an idea.



I agree that it would be very nice to know how the performance changes with use. The problem with cycling is that you can never get agreement on how the cells should be cycled, or if the cycling in the lab represents cycling in the field. It also takes quite a bit of time and ties up the test equipment. I don't think that I have enough time or equipment to commit to a cycling study.



Linger said:


> Cell recommendation: Eneloop Tones / Gen2 (1500cycle) eneloops. I do not have them to contribute at present (waiting for a deal at Dell.ca) Does any one have some gen2 eneloops to volunteer?



I have already tested the new "Gen 2" 1500x Eneloop and will post those results soon. Spoiler alert: they perform the same as the Gen 1 Eneloops.

Cheers,
BG


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## Battery Guy (Oct 22, 2010)

Greetings Everyone,

I have added the detailed test results for Elite 1700, Eneloop Gen 1, Eneloop Gen 2, Energizer 2300, Imedion 2400, Sanyo 2500 and Sanyo 2700. The constant current curves for the PowerGenix will be posted on Monday.

Any other batteries of interest?

Hope you guys find this useful.

Cheers,
BG


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## tandem (Oct 22, 2010)

Thanks for putting up the new cell types BG!

I'll break the ice and ask a question rather than pollute this fine thread with a guess that may be backasswards - using the Imedion 2400 constant current chart (compared to the Eneloop Gen 1) - what in a nutshell is the chart telling us about performance at different rates of current flow? What sort of applications would you prefer to use one cell over another?


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## Mr Happy (Oct 22, 2010)

tandem said:


> I'll break the ice and ask a question rather than pollute this fine thread with a guess that may be backasswards - using the Imedion 2400 constant current chart (compared to the Eneloop Gen 1) - what in a nutshell is the chart telling us about performance at different rates of current flow? What sort of applications would you prefer to use one cell over another?


The Immedion is showing significantly lower voltages under moderate to heavy loads, which would translate to lower brightness if used to drive an incandescent hotwire. At the same time it would deliver about 15 minutes extra run time.

You might choose the Immedion for light load applications where the run time is more important to you, such as in a digital camera. Of course, this chart does not tell you anything about durability, capacity maintenance, or self-discharge performance in the long term.


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## kxenl (Oct 23, 2010)

Hello Tandem! To me as a user of Pentax KX DSLR it tells me that Eneloop gives me about twice the runtime compered to Imedeon. Something like Eneloop 1250 mAh vs Imedeon 650 mAh when the voltage is too low for decent operation. Thanks for good info BG!


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## Battery Guy (Oct 23, 2010)

tandem said:


> Thanks for putting up the new cell types BG!
> 
> I'll break the ice and ask a question rather than pollute this fine thread with a guess that may be backasswards - using the Imedion 2400 constant current chart (compared to the Eneloop Gen 1) - what in a nutshell is the chart telling us about performance at different rates of current flow? What sort of applications would you prefer to use one cell over another?



I often use these curves to estimate how bright a hotwire mod will be with a different battery. An example would be the typical Mag 85 mod that uses a WA1185 bulb and 9 NiMH cells. From LuxLuthor's destructive testing, we see that the bulb draws ~3.5 amps. If I wanted to get an estimate of the brightness midway through discharge between an Eneloop and an Imedion, I would look at the voltage of the cells at about 1 Ah for ~3.5 amps. From the curves, I would estimate this voltage to be 1.15 V for the Eneloop and about 1.12 V for the Imedion. So for a 9 cell pack, that means 10.35 V for the Eneloop and 10.08 V for the Imedion. From Lux's testing, that would correspond to ~10% difference in lumen output, which I might be willing to live with to get the extra runtime from the Imedion.

If you repeated this analysis with the Elite 1700 cell, you would find that the 9 cell pack voltage would be ~11.2 V midway through discharge, which corresponds to ~30% increase in brightness over the Eneloops.

Cheers
BG


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## tandem (Oct 23, 2010)

Good info and examples folks, thanks.


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## Battery Guy (Nov 1, 2010)

Results for PowerGenix NiZn have been added.

Please let me know if you have any recommendations for other cells that should be added.

Cheers,
BG


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## Mr Happy (Nov 1, 2010)

The sustained high voltage at heavy load stands out for the NiZn.

It would be interesting to overlay NiZn and Energizer lithium on the same plot, given that NiZn is sometimes thought of as a rechargeable replacement for the lithiums. (But I'm not asking you to waste a bunch of L91s just for that purpose.)


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## Battery Guy (Nov 1, 2010)

Mr Happy said:


> It would be interesting to overlay NiZn and Energizer lithium on the same plot, given that NiZn is sometimes thought of as a rechargeable replacement for the lithiums. (But I'm not asking you to waste a bunch of L91s just for that purpose.)



Hi Mr. Happy,

A bunch of L91s would not be necessary since they really cannot sustain constant current loads above 3 amps. The L91s are normally considered to be high power cells, but when compared to most secondary cells, they really don't have the same power capabilities. 

I agree that the NiZn-L91 comparison would be interesting and I might do that test and post the results in a separate thread. Perhaps 0.5 A to 3 A discharge at 0.5 A increments? Target has L91s on sale for 7.99 a 4 pack this week and I would be willing to sacrifice $12 to run six tests on the L91 if people would get some value out of it.

Thanks for the suggestion Mr. Happy.

Cheers,
BG


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## InHisName (Mar 14, 2011)

This is my first time at trying the DeJaVu. I hope this turns out well.


*Re: The AA NiMH Performance Test Thread*
Written by *Battery Guy* on 02-19-2011 12:19 PM GMT



Russel said:


> So the estimation is derived mathematically,
> that makes sense. It is surprising how the Elite 1700 stands out so
> much. The last three plots (Discharge Energy (Wh), Energy Efficiency
> (%), and Energy Loss as Heat (Wh) vs Discharge Current (A)) really show
> the effect of internal resistance.


Yes, the Elite 1700 is really quite different from the other NiMH
cells, and it does have spectacular high rate performance. I only wish
that someone would make an LSD cell that had similar performance 
characteristics. The big problem with the Elite 1700 is a high 
self-discharge, and relatively high self-discharge rate variability from
cell-to-cell. This means that you need to "rebalance" a multi-cell 
pack relatively relatively frequently by charging at a low rate. Yes, the Elite 1700 is really quite different from the other NiMH
cells, and it does have spectacular high rate performance. I only wish
that someone would make an LSD cell that had similar performance 
characteristics. The big problem with the Elite 1700 is a high 
self-discharge, and relatively high self-discharge rate variability from
cell-to-cell. This means that you need to "rebalance" a multi-cell 
pack relatively relatively frequently by charging at a low rate.

*Re: The AA NiMH Performance Test Thread*
Written by *Battery Guy* on 02-21-2011 08:19 AM GMT

Discharge curves have been added for the Tenergy 2300 LSD AA cell. 
I had high hopes for this cell based on a couple posts in other 
threads, but its performance really let me down. The IEC discharge 
capacity was only 1.98 Ah, and the cell has substantial voltage sag at 
higher currents.

From an "out of the package" performance perspective, this cell is 
definitely worst in class, at least for the LSD cells I have tested so 
far.

*Re: The AA NiMH Performance Test Thread*
Written by *InHisName* on Yesterday 04:25 AM GMT

Great new plots! Battery Guy

Two of them really show differences in that I kept seeing Eneloopxx, 
TruCell, Energizer2300, and Eneloops all coming in "2nd" to the 1700.

Since I have plenty of cells I'll probably only jump if any one has 
bargain offerings somewhere. I wouldn't mind trying 4 or 8 if I 

*Re: The AA NiMH Performance Test Thread*
Written by *080* on Yesterday 06:47 PM GMT

Hello, anyone ever tested or have experience with the AA*turnigy* low self discharge (not tenergy) 

battery from HobbyKing. They are 2200mah and consistently charge to 
2350mah. Any data knowledge appreciated especially for use in torches.

*Re: The AA NiMH Performance Test Thread*
Written by *Mr Happy* on Yesterday 07:59 PM GMT



080 said:


> Hello, anyone ever tested or have experience with the AA *turnigy* low self discharge (not tenergy)
> 
> battery from HobbyKing. They are 2200mah and consistently charge to
> 2350mah. Any data knowledge appreciated especially for use in torches.


There are two kinds of battery in the world: there are Eneloops 
and there is everything else. The Turnigy batteries are not Eneloops... There are two kinds of battery in the world: there are Eneloops 
and there is everything else. The Turnigy batteries are not Eneloops...

discovered approx $1 per cell.


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## Battery Guy (Mar 19, 2011)

I have updated the first post in this thread and added the lost content from the server crash. 

And a special thanks to InHisName for adding the lost threads!

Cheers,
BG


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## JA(me)S (Mar 19, 2011)

*deleted*


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## JA(me)S (Mar 25, 2011)

Below are all cached posts from November 2 2010 through to the end of February 2011.
This represents original posts sequentially from #14-95.
No information was lost in this thread when the lights went out at CPF. 

A special thank you to InHisName for finding posts 91-95.:thumbsup:


 
*Re: The AA NiMH Performance Test Thread* Written by *Battery Guy* on 12-03-2010 02:37 PM GMT 

Greetings Everyone Data for GP Recyko AA NiMH cells have been added to the first post. Enjoy! Cheers, BG



*Re: The AA NiMH Performance Test Thread* Written by *brainy1000* on 12-03-2010 05:15 PM GMT 

Many thanks for your time and efforts, lots of valuable info here, specially for including the ReCykos! :thumbsup:



*Re: The AA NiMH Performance Test Thread* Written by *LetThereBeLite* on 12-05-2010 02:49 AM GMT



Battery Guy said:


> Greetings Everyone, One cell is hardly what I would call a statistically significant sample. There is certainly going to be variability in cell performance, so please recognize this limitation. Unfortunately, I do not have the time to repeat this work on multiple samples. * Also, this testing does not take into account performance degradation that occurs over time due to aging and cycling (except for the Shnoopaloop constant current tests)*. These results are what you might expect for new cells. Exactly how the cells degrade will depend on the cell design, manufacturing quality and your use/abuse pattern. *Shnoopaloops*: These are Duraloops purchased from Shnoop. They are essentially three year old Eneloops. See here for the thread to read more detail.
> 
> 
> 
> Cheers, BG


 Hi BG, thanks for your time and effort in conducting the tests and then posting the results. :thumbsup: Much appreciate it! I have a few clarification questions, if I may. I'm curious to know what, if anything, you did to your control GEN-1 eneloop before conducting the discharge test on your Maccor 4300 tester. I.e., did the eneloop undergo one, or several, break-in forming charge(s) before being discharged on the Maccor 4300 test? Did you cycle charge it a few/several times before conducting the discharge test, or did you just charge it to full once straight out of the package and immediately conducted the Maccor Discharge test? Secondly, with regards to the Schnoopaloop used in the above graph, what, if anything, did you do to it prior to conducting the Maccor Discharge test? Was it formed charged--once or several times--before the Discharge test? Was it cycle charged a few times before conducting the Discharge test? Looking at your graph above, it seems to indicate there may be some voltage depression of the Schnoopaloop given its age. So I'm really curious whether you tested it straight out of the package--without any forming break-in charges or cycle charges to remove or reduce the voltage depression--or whether you 'broke' it in first before discharge testing it. I'd appreciate the clarification. Thanks! I'm hoping that 3, or more, cycles of 'break-in' on the Maha C9000 would/will help reduce the voltage depression of the Schnoopaloop to a negligible amount. But if you can confirm that you repeatedly 'broke' in the Schnoopaloop before conducting the Discharge Test, then I have less hope to be optimistic about reducing/eliminating the voltage depression indicated by your graph. I purchased 12 AAs and 4 of them have just been 'discharged' on my C9000. They are currently running through their obligatory 'break-in' cycle. I will report my test results in the other Schnoopaloop thread--so as not to clutter your thread here. 



*Re: The AA NiMH Performance Test Thread* Written by *Battery Guy* on 12-05-2010 06:18 AM GMT



LetThereBeLite said:


> I'm curious to know what, if anything, you did to your control GEN-1 eneloop before conducting the discharge test on your Maccor 4300 tester. I.e., did the eneloop undergo one, or several, break-in forming charge(s) before being discharged on the Maccor 4300 test? Did you cycle charge it a few/several times before conducting the discharge test, or did you just charge it to full once straight out of the package and immediately conducted the Maccor Discharge test? Secondly, with regards to the Schnoopaloop used in the above graph, what, if anything, did you do to it prior to conducting the Maccor Discharge test? Was it formed charged--once or several times--before the Discharge test? Was it cycle charged a few times before conducting the Discharge test? Looking at your graph above, it seems to indicate there may be some voltage depression of the Schnoopaloop given its age. So I'm really curious whether you tested it straight out of the package--without any forming break-in charges or cycle charges to remove or reduce the voltage depression--or whether you 'broke' it in first before discharge testing it.


 I usually test everything directly out of the package, with only an initial discharge at 0.5 A or 1 A to bring the cell down to 0% SOC before applying the first charge. But, looking back at my notes, it appears that I did indeed run the Shnoopaloops through a break-in cycle on my C9000 prior to running the tests. Cheers, BG



*Re: The AA NiMH Performance Test Thread* Written by *Mikl1984* on 12-05-2010 06:31 AM GMT



Battery Guy said:


> I usually test everything directly out of the package, with only an initial discharge at 0.5 A or 1 A to bring the cell down to 0% SOC before applying the first charge.


 It's not right  according IEC 61951-2 You should discharge at 0.2C before charge at 0.1C withing 16 hours Maha's Break-In is almost follows all IEC recomendations (except discharge till 0.9V contrary 1.0V IEC)



*Re: The AA NiMH Performance Test Thread* Written by *LetThereBeLite* on 12-05-2010 06:45 AM GMT



Battery Guy said:


> I usually test everything directly out of the package, with only an initial discharge at 0.5 A or 1 A to bring the cell down to 0% SOC before applying the first charge. But, looking back at my notes, it appears that I did indeed run the Shnoopaloops through *a* break-in cycle on my C9000 prior to running the tests. Cheers, BG


 Thanks for the response BG. You state "a" break-in cycle, so I'm interpreting that to mean *one *break-in cycle. I've read elsewhere that cells which suffer from voltage depression can be "cured" (but really I think helped is a better word) with several cycles of full discharge then recharge. Do you think you could try this and then repeat your test, *when you have time*? What I'm asking is that, when you have time, you use the '*cycle*' feature on the Maha C9000 and cycle the Shnoopaloops for 5 times, then try the Discharge Test on your Maccor 4300 again. I'm really curious to see if the voltage depression seen on the Shnoopaloops will improve--or can be improved--or stay the same as your original test. Thanks much! http://www.stefanv.com/electronics/u...tml#depression


> Fortunately, voltage depression can be cured. Fully discharging and then recharging a battery two or three times usually brings the voltage back to where it should be. A battery manager is ideal for this.


*


Re: The AA NiMH Performance Test Thread* Written by *Battery Guy* on 12-05-2010 06:56 AM GMT 



Mikl1984 said:


> It's not right  according IEC 61951-2 You should discharge at 0.2C before charge at 0.1C withing 16 hours Maha's Break-In is almost follows all IEC recomendations (except discharge till 0.9V contrary 1.0V IEC)


 Correct me if I am wrong, but the IEC 61951-2 standard is for measuring and reporting the total cell capacity. If so, I don't think that it applies for these tests. Cheers, BG



*Re: The AA NiMH Performance Test Thread* Written by *Battery Guy* on 12-05-2010 07:02 AM GMT 



LetThereBeLite said:


> Thanks for the response BG. You state "a" break-in cycle, so I'm interpreting that to mean *one *break-in cycle. I've read elsewhere that cells which suffer from voltage depression can be "cured" (but really I think helped is a better word) with several cycles of full discharge then recharge. Do you think you could try this and then repeat your test, *when you have time*? What I'm asking is that, when you have time, you use the '*cycle*' feature on the Maha C9000 and cycle the Shnoopaloops for 5 times, then try the Discharge Test on your Maccor 4300 again. I'm really curious to see if the voltage depression seen on the Shnoopaloops will improve--or can be improved--or stay the same as your original test. Thanks much! http://www.stefanv.com/electronics/u...tml#depression


 Correct, I only did one break-in cycle on the Shnoopaloops. However, I do not believe that the Shnoopaloops are suffering from "voltage depression", as it is commonly understood. The Shnoopaloops are suffering from having a higher internal resistance, so if you discharge them very slow, they have the same voltage as new eneloops. With voltage depression, the cell discharges at a lower voltage even at relatively low discharge rates. This is why I do not think that running additional break-in cycles will have an impact, but it is worth a try if you are curious. Cheers, BG



*Re: The AA NiMH Performance Test Thread* Written by *LetThereBeLite* on 12-05-2010 07:10 AM GMT



Battery Guy said:


> Correct, I only did one break-in cycle on the Shnoopaloops. However, I do not believe that the Shnoopaloops are suffering from "voltage depression", as it is commonly understood. The Shnoopaloops are suffering from having a higher internal resistance, so if you discharge them very slow, they have the same voltage as new eneloops. *With voltage depression, the cell discharges at a lower voltage even at relatively low discharge rates. This is why I do not think that running additional break-in cycles will have an impact*, but it is worth a try* if you are curious*. Cheers, BG


 Thanks for the explanation. That makes sense. As for me being curious, yes I am.  I purchased 12 of those Shnoopaloops and I would like to hope that there is something that can be done to improve their performance. As I don't have your testing equipment, I can't test it myself and thus must ask you for help in quenching my thirst for this info. But I realize you're busy and your test equipment is meant for "real work", so as I emphasized above, please do these cycles only at your leisure and as time and equipment permits. Thanks.



*Re: The AA NiMH Performance Test Thread* Written by *Mikl1984* on 12-05-2010 08:48 AM GMT



Battery Guy said:


> Correct me if I am wrong, but the IEC 61951-2 standard is for measuring and reporting the total cell capacity. If so, I don't think that it applies for these tests.


 You are wrong  I have russian translation of this standard http://www.gostu.ru/data/18985.pdf But numbers are international  Standard discribe total cell capacity but in 0.2C till 1V; 1C, 5C, 10C till 0.9V. Also discribe cycling, different temperature testing(for example 0 Celsius at 2 and 3C till 0.8V), overcharge conditions etc. Your test are really interesting but will be even more useful if it comply IEC mA



*Re: The AA NiMH Performance Test Thread* Written by *Mr Happy* on 12-05-2010 11:00 AM GMT



Mikl1984 said:


> You are wrong  I have russian translation of this standard http://www.gostu.ru/data/18985.pdf But numbers are international  Standard discribe total cell capacity but in 0.2C till 1V; 1C, 5C, 10C till 0.9V. Also discribe cycling, different temperature testing(for example 0 Celsius at 2 and 3C till 0.8V), overcharge conditions etc. Your test are really interesting but will be even more useful if it comply IEC mA


 I think Battery Guy is doing fine  It is only important to follow the IEC standard test protocol if you are reporting results according to that standard. It is not "wrong" to use other procedures if you describe those procedures and are consistent in applying them. In this case BG simply said he discharged the cell before charging it. That is a good procedure and is exactly what I do too.



*Re: The AA NiMH Performance Test Thread* Written by *Mikl1984* on 12-05-2010 11:35 AM GMT 

You are wrong too  According * 5.3 Measuring Battery Energy [FONT=Times New Roman,Times New Roman][FONT=Times New Roman,Times New Roman] The battery shall be charged, according to Section 5.1 of this test methodology. After charging, the battery shall be stored in an ambient temperature of 20 °C ± 5 °C for not less than 1 hour and not more than 4 hours. The battery shall then be discharged in an ambient temperature of 20 °C ± 5 °C at a rate of 0.2C, where C is the rated Ampere-hour capacity of the battery. The test shall continue until the battery pack reaches its end of discharge voltage, according to Table 1. During this period, voltage shall be logged, integrated at the end of discharge, and multiplied by the discharge rate to obtain battery energy. The test may be repeated a maximum of 5 times, as in IEC 61951, with the best result being chosen as the final measured energy value. [/FONT][/FONT]*http://www.energystar.gov/ia/partner...est_Method.pdf I only recommend: - to follow charge and conditioning IEC standards to receive reliable results - to add 0.2C and 1C discharge test to test pattern



*Re: The AA NiMH Performance Test Thread* Written by *Battery Guy* on 12-05-2010 02:23 PM GMT



Mikl1984 said:


> You are wrong too  According * 5.3 Measuring Battery Energy [FONT=Times New Roman,Times New Roman][FONT=Times New Roman,Times New Roman] The battery shall be charged, according to Section 5.1 of this test methodology. After charging, the battery shall be stored in an ambient temperature of 20 °C ± 5 °C for not less than 1 hour and not more than 4 hours. The battery shall then be discharged in an ambient temperature of 20 °C ± 5 °C at a rate of 0.2C, where C is the rated Ampere-hour capacity of the battery. The test shall continue until the battery pack reaches its end of discharge voltage, according to Table 1. During this period, voltage shall be logged, integrated at the end of discharge, and multiplied by the discharge rate to obtain battery energy. The test may be repeated a maximum of 5 times, as in IEC 61951, with the best result being chosen as the final measured energy value. [/FONT][/FONT]*http://www.energystar.gov/ia/partner...est_Method.pdf I only recommend: - to follow charge and conditioning IEC standards to receive reliable results - to add 0.2C and 1C discharge test to test pattern


 Hi Mikl1984 I am familiar with the IEC standards, and again it is not the purpose of my tests to report the cell capacity. The purpose of the IEC standards is to provide cell manufacturers with a standardized way of reporting total cell capacity. The purpose of my tests is to see how the cells perform at different discharge currents. I like your recommendations. I can begin adding an IEC 0.2C discharge curve to the tests and will do so from this point forward. However, I am not really sure how much value that will be for other CPF members because many people already have the ability to make those measurements with the Maha C9000 and other chargers. For the 1 A through 10 A discharge curves, I simply do not have the time to perform the 0.1C charge for 16 hours. This would effectively add 160 hours of instrument time to each test, and I simply cannot dedicate that kind of time. I would like to add one additional comment regarding standardized test protocols. Having participated in my fair share of developing standardized tests, I can tell you that they seldom represent the best way to perform a measurement. Inevitably, the standardized tests end up being a compromise between the participants in the standards committee because there are always competing interests. Again, thank you Mikl1984 for bringing these issues to light. Cheers, BG



*Re: The AA NiMH Performance Test Thread* Written by *Mikl1984* on 12-05-2010 10:06 PM GMT 

Hi BG Thanks for understanding  my bad English I just want to add, that proposed tests according IEC will help standard users to check manufacture's data, which usually too good  to be real. Of course every Maha's user are able to plot discharging curve manually. http://www.candlepowerforums.com/vb/...-via-Maha-data But on your professional equipment it will be more correct



*Re: The AA NiMH Performance Test Thread* Written by *LetThereBeLite* on 12-07-2010 07:25 AM GMT 

BG, may I ask what you're currently testing for CPF, as opposed to testing for 'real work'.  Alternatively, if you're currently not testing anything for CPF, what battery is planned for testing? Thanks!



*Re: The AA NiMH Performance Test Thread* Written by *Battery Guy* on 12-07-2010 06:26 PM GMT



LetThereBeLite said:


> BG, may I ask what you're currently testing for CPF, as opposed to testing for 'real work'.  Alternatively, if you're currently not testing anything for CPF, what battery is planned for testing?


 Unfortunately, "real work" is taking priority for the foreseeable future. Next on the list is the new Eneloop XX cells. I have them on order but probably won't receive them for a week or two since they are being shipped from the EU. Cheers, BG


----------



## JA(me)S (Mar 25, 2011)

*Re: The AA NiMH Performance Test Thread* Written by *LetThereBeLite* on 12-07-2010 06:34 PM GMT



Battery Guy said:


> Unfortunately, "real work" is taking priority for the foreseeable future. Next on the list is the new Eneloop *XX* cells. I have them on order but probably won't receive them for a week or two since they are being shipped from the EU. Cheers, BG


 Alrighty. I look forward seeing the test results. 



*Re: The AA NiMH Performance Test Thread* Written by *Mikl1984* on 12-07-2010 10:23 PM GMT



Battery Guy said:


> Next on the list is the new Eneloop XX cells.


 Any plans for AAA testing?



*Re: The AA NiMH Performance Test Thread* Written by *MichaelW* on 12-08-2010 01:24 PM GMT



Battery Guy said:


> Hi Mr. Happy, A bunch of L91s would not be necessary since they really cannot sustain constant current loads above 3 amps. The L91s are normally considered to be high power cells, but when compared to most secondary cells, they really don't have the same power capabilities. I agree that the NiZn-L91 comparison would be interesting and I might do that test and post the results in a separate thread. Perhaps 0.5 A to 3 A discharge at 0.5 A increments? Target has L91s on sale for 7.99 a 4 pack this week and I would be willing to sacrifice $12 to run six tests on the L91 if people would get some value out of it. Thanks for the suggestion Mr. Happy. Cheers, BG


 If [when] 4sevens puts the Cree xm-l into the QuarkMini AAx2, what cells would be optimal? A 14500 in a QMini AAx1 is probably going to be unusable on Maximum output mode [Vf @ 3 amps is 3.35 volts] and splitting a CR-V3 is going to be too expensive (so that you match the output of a QMini 123) The Vf of the xm-l at 2.1 amps is 3.2 volts so, NiZn or primary lithium AAs (be it L91 or Duracell Ultra Lithium [is that available in the US?] ) for the QMini AAx2? Thanks.



*Re: The AA NiMH Performance Test Thread* Written by *Battery Guy* on 12-09-2010 07:19 PM GMT



MichaelW said:


> The Vf of the xm-l at 2.1 amps is 3.2 volts so, NiZn or primary lithium AAs (be it L91 or Duracell Ultra Lithium [is that available in the US?] ) for the QMini AAx2?


 I know nothing of the QMini AA flashlights, so I don't know if they are direct drive or regulated. Let's simply assume that the average per cell discharge will be between 2 and 2.5 W (I am using your current and voltage numbers to get at that range). If you look at the http://www.candlepowerforums.com/vb/showthread.php?278063-AA-Ragone-PlotAA Ragone plot, you will see that at a 2 W discharge, the Energizer L91 will last about 1.3 hours and the Duracell Ultra Lithium (not available in the US) will last a bit longer at 1.7 hours. The PowerGenix will last about 1.1 hours, but it of course is rechargeable. If you now look at 2.5 W discharge, the PowerGenix is at 1 hour, the Energizer is at about 1.1 hours and the Duracell is at about 1.3 hours. So unless you need to use this flashlight at temperature extremes (e.g. your car in the summer and/or winter), this seems like it would be a great application for the PowerGenix cells. The performance is a bit lower, but of course they are rechargeable and you can often find them on sale with a charger for less than the cost of the Energizer Ultimate Lithium cells. Hope that helps. Cheers, BG



*Re: The AA NiMH Performance Test Thread* Written by *Battery Guy* on 12-09-2010 07:23 PM GMT 



Mikl1984 said:


> Any plans for AAA testing?


 Nothing planned. Sorry! The AA's have been keeping me busy, and I would really like to do more with lithium-ions.



*Re: The AA NiMH Performance Test Thread* Written by *MichaelW* on 12-09-2010 08:27 PM GMT 

How about a graphical explanation of the QMini family? http://i243.photobucket.com/albums/f.../2AA-HiEne.gif http://i243.photobucket.com/albums/f.../2AA-HiL91.gif http://i243.photobucket.com/albums/f...2AA-HiAlka.gif http://i243.photobucket.com/albums/f...3-HiCR123A.gif http://i243.photobucket.com/albums/f...r123-HiRCR.gif http://i243.photobucket.com/albums/f...niAA-HiL91.gif http://i243.photobucket.com/albums/f...niAA-HiEne.gif http://i243.photobucket.com/albums/f...iAA-HiAlka.gif http://i243.photobucket.com/albums/f...AA-Hi14500.gif With the circuit it is using, more voltage is good. Too much becomes wasteful. A RCR or 14500 in the QMini123 / AA is good for showing off, but will get 2nd degree burn hot with the xm-l. 1st degree burn hot with 2xNiZn in a QMini AAx2 package is okay :thumbsup: Friends don't let friends use alkalines indeed.



*Re: The AA NiMH Performance Test Thread* Written by *Battery Guy* on 12-14-2010 09:03 PM GMT



MichaelW said:


> How about a graphical explanation of the QMini family? http://i243.photobucket.com/albums/f.../2AA-HiEne.gif http://i243.photobucket.com/albums/f.../2AA-HiL91.gif http://i243.photobucket.com/albums/f...2AA-HiAlka.gif http://i243.photobucket.com/albums/f...3-HiCR123A.gif http://i243.photobucket.com/albums/f...r123-HiRCR.gif http://i243.photobucket.com/albums/f...niAA-HiL91.gif http://i243.photobucket.com/albums/f...niAA-HiEne.gif http://i243.photobucket.com/albums/f...iAA-HiAlka.gif http://i243.photobucket.com/albums/f...AA-Hi14500.gif With the circuit it is using, more voltage is good. Too much becomes wasteful. A RCR or 14500 in the QMini123 / AA is good for showing off, but will get 2nd degree burn hot with the xm-l. 1st degree burn hot with 2xNiZn in a QMini AAx2 package is okay :thumbsup: Friends don't let friends use alkalines indeed.


 In those plots, what is the y-axis relative to? In other words, what is the baseline 100% value setup?



*Re: The AA NiMH Performance Test Thread* Written by *MichaelW* on 12-14-2010 10:15 PM GMT 

See: http://www.candlepowerforums.com/vb/...lues-to-Lumens and http://www.sliderule.ca/FL1.htm



*Re: The AA NiMH Performance Test Thread* Written by *Battery Guy* on 01-03-2011 02:24 PM GMT

Greetings Everyone I know that it has been a long wait, but I have finally added the Eneloop XX data to the first post in this thread. Note that I have only finished the constant current discharge curves. I will be posting the data for the Ragone plot in a few days. My initial impression is very favorable. I had expected these to perform on par with the Imedion 2400, Sanyo 2500 or Sanyo 2700. In fact, they perform nearly as good as the original Eneloops even at very high discharge currents. :thumbsup: Cheers, BG



*Re: The AA NiMH Performance Test Thread* Written by *LetThereBeLite* on 01-03-2011 02:38 PM GMT



Battery Guy said:


> Greetings Everyone I know that it has been a long wait, but I have finally added the Eneloop XX data to the first post in this thread. Note that I have only finished the constant current discharge curves. I will be posting the data for the Ragone plot in a few days. *My initial impression is very favorable. * I had expected these to perform on par with the Imedion 2400, Sanyo 2500 or Sanyo 2700. In fact, they perform nearly as good as the original Eneloops even at very high discharge currents. :thumbsup: Cheers, BG


 BG, you should have had more faith in eneloop technology.  I knew the XX wouldn't let us down. I'll definitely buy a pack when it eventually makes it to stateside. Thanks for doing the testing and getting us the empirical data. :thumbsup:



*Re: The AA NiMH Performance Test Thread* Written by *BVH* on 01-03-2011 06:42 PM GMT 

Great to see they aretesting out well! Thank you BG for the data.



*Re: The AA NiMH Performance Test Thread* Written by *Battery Guy* on 01-03-2011 08:06 PM GMT



LetThereBeLite said:


> BG, you should have had more faith in eneloop technology.  I knew the XX wouldn't let us down.


 Sorry, but I am not a "have faith" kind of guy. I am a "show me the data" kind of guy...and Sanyo continues to deliver from this perspective with regards to the Eneloops. What surprises me about the new Eneloop XX cells is how much better they perform at high rate compared to the "standard" Sanyo 2500 and Sanyo 2700 cells. In fact, the Eneloop XX cells appear to have higher capacity and better voltage retention than either the Sanyo 2500 or 2700 cells, at least under my testing conditions. Quite frankly, from an initial performance standpoint, it looks like the substantial capacity increase in the Eneloop XX compared to the standard Eneloop is more than worth the very small decrease in voltage retention. Indeed, only the highest power applications (>5 amp) would even notice the difference. Seems like a pretty darn good trade-off to me. The other cell that continues to surprise me is the Elite 1700. That particular NiMH cell performs much better than ANY other NiMH cell with respect to voltage retention. And you only sacrifice 300 mAh compared to the Eneloop for that extra power capability. So right now I would have to say that my favorite AA NiMH cells are the new Eneloop XX and the Elite 1700, as they seem to represent the best of both classes of cells. Unfortunately, the only way to buy the Eneloop XX cells in North America is to mail order them from Europe. Even before shipping the new Eneloop XX cells are 2X the cost of standard Eneloops. Hopefully these will become more readily available and cheaper in the near future. Cheers, BG



*Re: The AA NiMH Performance Test Thread* Written by *Burgess* on 01-03-2011 08:09 PM GMT

to Battery_Guy -- *Thank You* for your time and effort and dedication. :goodjob: Really appreciate seeing yer' data on the new Sanyo XXeloops ! Gonna' hafta' buy a few packs, when they come to U.S.A. :thumbsup: _



*Re: The AA NiMH Performance Test Thread* Written by *fishinfool* on 01-04-2011 01:20 AM GMT

Thanks for all of your hard work Battery Guy! I can't wait until these XXeloops start showing up stateside. Hopefully sometime this year......hopefully.



*Re: The AA NiMH Performance Test Thread* Written by *Battery Guy* on 01-05-2011 06:01 PM GMT

Greetings Everyone The results for the Eneloop XX have now been added to the Ragone plot in the first post. Also, at the end of the first post you will notice that I added two new plots. These plots are simply another way of looking at data that were collected from the 1A-10A constant current tests. One plot shows the effect of discharge current on total available energy. The other plot shows the effect of discharge current on the efficiency of the cell. I have replaced the Eneloops in my Mag85 with XXeloops. That gives me a real, honest runtime of ~40 minutes, compared to ~32 minutes with standard Eneloops. It sure ain't worth the 2X in cost that I paid, but it is nice to see that the improvement is consistent with expectations. Next cell on the list: AccuEvolution! Cheers, BG



*Re: The AA NiMH Performance Test Thread* Written by *LetThereBeLite* on 01-05-2011 06:37 PM GMT



Battery Guy said:


> *Sorry, but I am not a "have faith" kind of guy. I am a "show me the data" kind of guy*...and Sanyo continues to deliver from this perspective with regards to the Eneloops. BG


 I can't argue with that logic.  I certainly appreciate your empirical data. Nevertheless, I didn't have much suspicion that Sanyo would let us down with their XX loops. I'm happy to see your empirical data confirming it.



*Re: The AA NiMH Performance Test Thread* Written by *Mikl1984* on 01-05-2011 11:03 PM GMT 



Battery Guy said:


> Also, at the end of the first post you will notice that I added two new plots. These plots are simply another way of looking at data that were collected from the 1A-10A constant current tests. One plot shows the effect of discharge current on total available energy. The other plot shows the effect of discharge current on the efficiency of the cell.


 Those graphs are really interesting! Thanks for your work Have you any plan to test LSD (may be on 1A only) after 1(3, 6, 12) month ? Selfdischarge decrease not only mAh, but V also. Therefore energy tests become even more interesting Didn't find promising  0.2C curves 



*Re: The AA NiMH Performance Test Thread* Written by *Battery Guy* on 01-06-2011 05:51 AM GMT 



Mikl1984 said:


> Those graphs are really interesting! Thanks for your work Have you any plan to test LSD (may be on 1A only) after 1(3, 6, 12) month ? Selfdischarge decrease not only mAh, but V also. Therefore energy tests become even more interesting


 I have thought about doing some self-discharge measurements, but right now those plans are still being formulated.


Mikl1984 said:


> Didn't find promising  0.2C curves


 They are coming! I made the IEC charge/discharge measurement on the Sanyo XX and I am in the process of doing it for the other cells. Cheers, BG



*Re: The AA NiMH Performance Test Thread* Written by *Battery Guy* on 01-07-2011 12:23 PM GMT 



Mikl1984 said:


> Didn't find promising  0.2C curves


 Take a look now. 0.2C discharge curves (performed in accordance with the IEC standard) have been added for the standard Eneloop, Imedion 2400, Energizer 2300, Sanyo 2500, Sanyo 2700 and XXeloop cells. I hope to get the ones for the Elite 1700 and GP Recyko cells in a week or so. You might be interested to know that the IEC capacity of the XXeloop was 2.5001 Ah. That is pretty darn accurate manufacturing if you ask me. I wonder if the precision of their manufacturing is equally as impressive. Hope you find this useful. Cheers, BG



*Re: The AA NiMH Performance Test Thread* Written by *purduephotog* on 01-07-2011 01:20 PM GMT 

Dare I ask about the Tenergy brands? If I shipped a cell or two? (I need to buy some in the coming months to replace a few that have been totally drained in the baby bouncer....)



*Re: The AA NiMH Performance Test Thread* Written by *Battery Guy* on 01-07-2011 02:48 PM GMT 



purduephotog said:


> Dare I ask about the Tenergy brands? If I shipped a cell or two? (I need to buy some in the coming months to replace a few that have been totally drained in the baby bouncer....)


 You may indeed dare. These are non-LSD, correct?



*Re: The AA NiMH Performance Test Thread* Written by *LetThereBeLite* on 01-07-2011 04:22 PM GMT 



Battery Guy said:


> Take a look now. 0.2C discharge curves (performed in accordance with the IEC standard) have been added for the standard Eneloop, Imedion 2400, Energizer 2300, Sanyo 2500, Sanyo 2700 and XXeloop cells. *I hope to get the ones for the Elite 1700 and GP Recyko cells in a week or so. * You might be interested to know that the IEC capacity of the XXeloop was 2.5001 Ah. That is pretty darn accurate manufacturing if you ask me. I wonder if the precision of their manufacturing is equally as impressive. Hope you find this useful. Cheers, BG


 Thanks for the new data BG! Nice work! Would you consider getting this data for the Schnooloops as well? Thanks!



*Re: The AA NiMH Performance Test Thread* Written by *EntropyQ3* on 01-07-2011 04:53 PM GMT 

Awesomeperformance from the new Eneloop XX! Better than I would have guessed, and shows both that Sanyo is on top of their game, and more generally, that true improvement is still to be had in this field. I hope this technology is put to use in AAA size batteries since both capacity and performance under load are more critical for AAA, and not only for flashlight use.



*Re: The AA NiMH Performance Test Thread* Written by *Mikl1984* on 01-07-2011 10:00 PM GMT 



Battery Guy said:


> Take a look now. 0.2C discharge curves (performed in accordance with the IEC standard) have been added for the standard Eneloop, Imedion 2400, Energizer 2300, Sanyo 2500, Sanyo 2700 and XXeloop cells. You might be interested to know that the IEC capacity of the XXeloop was 2.5001 Ah.


 Thanks BG I hope it will be interesting not for me only  One remark. According IEC capacity during 0.2C discharge should measure till 1V, not 0.8V as in your tests What's show XXeloop on this limit? And question about accuracy of your device. Are you checked V measurement with good DMM?



*Re: The AA NiMH Performance Test Thread* Written by *LetThereBeLite* on 01-07-2011 10:13 PM GMT 



Mikl1984 said:


> Thanks BG I hope it will be interesting not for me only  One remark. According IEC capacity during 0.2C discharge should measure till 1V, not 0.8V as in your tests What's show XXeloop on this limit? And question about accuracy of your device. Are you checked V measurement with good DMM?


 Hmm. that's interesting. Does the Maha C9000 discharge to .9v or 1v when in its break-in mode? Likewise for Refresh & Analyze, is it discharging to .9v or 1v? I always thought the Maha C9000 was discharging to .9v.



*Re: The AA NiMH Performance Test Thread* Written by *Mikl1984* on 01-07-2011 10:52 PM GMT 

Maha discharge till 0.9V during break-in (R&A and Discharge too) And it's only difference in comparison IEC recommendation for 16-hours 0.1C charge and 0.2C discharge after 1 hour



*Re: The AA NiMH Performance Test Thread* Written by *shadowjk* on 01-08-2011 02:50 AM GMT 

Also I think Maha uses pulsed charging and discharging, which is also different from IEC recommendation?



*Re: The AA NiMH Performance Test Thread* Written by *Mikl1984* on 01-08-2011 03:41 AM GMT 

Yes, it's true But due to this you are able to control V during process for example



*Re: The AA NiMH Performance Test Thread* Written by *Battery Guy* on 01-08-2011 07:03 AM GMT 



Mikl1984 said:


> One remark. According IEC capacity during 0.2C discharge should measure till 1V, not 0.8V as in your tests What's show XXeloop on this limit?


 You can read them off the graph, but if you want more accurate results, here you go: 2.4801 Ah at 1.0001 V 2.4935 Ah at 0.9006 V 2.5001 Ah at 0.8000 V


Mikl1984 said:


> And question about accuracy of your device. Are you checked V measurement with good DMM?


 I use a calibrated Maccor series 4300 battery test system. Most of these tests are run on 0-10V channels with a 0-10A current range. The accuracy of the system is +/-0.02% of full system resolution, which means +/-0.02% of 10 V or 10 A, which is +/-0.2 mV and +/-0.2 mA. Actually, the IEC tests were run with a 0-5 A range, which means that the current accuracy of the IEC tests is +/-0.1 mA. As I mentioned, the system is calibrated. I use the Maccor calibration system, and I double check occasionally with a calibrated Fluke 187 or 189 (I can't remember which one right now). Cheers, BG



*Re: The AA NiMH Performance Test Thread* Written by *Battery Guy* on 01-08-2011 08:01 AM GMT 



LetThereBeLite said:


> Thanks for the new data BG! Nice work! Would you consider getting this data for the Schnooloops as well? Thanks!


 Sure. Not a problem. Cheers, BG


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## JA(me)S (Mar 25, 2011)

*Re: The AA NiMH Performance Test Thread* Written by *Mikl1984* on 01-08-2011 09:51 AM GMT 

Thanks for figures and explanations about accuracy What's difference between Maccor and Maha data? Question is due to my measurements http://www.candlepowerforums.com/vb/...d.php?t=303342



*Re: The AA NiMH Performance Test Thread* Written by *45/70* on 01-08-2011 11:55 AM GMT 

Hi BG. Not getting super technical about it, I find it interesting how the Mahas come very close to the IEC 0.2 discharge info you obtained. My results with my Maha C9000's as I remember anyway, were pretty much spot on with your results for the original eneloops, Sanyo Industrial 2500's. and the Sanyo 2700's. If the Maha's are off, on the discharge results, all I can say, is that they appear to be good enough for my personal use anyway. I'm surprised that they are that close, really. Dave



*Re: The AA NiMH Performance Test Thread* Written by *Battery Guy* on 01-08-2011 01:38 PM GMT 



Mikl1984 said:


> Thanks for figures and explanations about accuracy What's difference between Maccor and Maha data? Question is due to my measurements http://www.candlepowerforums.com/vb/...d.php?t=303342


 Is there a difference? Technically, there should not be any difference, other than the relative accuracy of the Maha and Maccor, and variability between cells.


45/70 said:


> Hi BG. Not getting super technical about it, I find it interesting how the Mahas come very close to the IEC 0.2 discharge info you obtained. My results with my Maha C9000's as I remember anyway, were pretty much spot on with your results for the original eneloops, Sanyo Industrial 2500's. and the Sanyo 2700's. If the Maha's are off, on the discharge results, all I can say, is that they appear to be good enough for my personal use anyway. I'm surprised that they are that close, really. Dave


 I completely agree Dave. I think that the Maha and Maccor results agree very well. I hope that I was not giving the impression that I thought the Maha is deficient with respect to its accuracy. Indeed, for the price, I am very, very impressed with the Maha C9000. Cheers, BG



*Re: The AA NiMH Performance Test Thread* Written by *LetThereBeLite* on 01-08-2011 02:57 PM GMT 

Well, the Maha discharges to .9v and the IEC specs call for discharges to 1.0v. (I wasn't aware of this difference before. I thought the IEC called for discharging to .9v and that's why Maha discharges to .9v) BG discharges to .8v on his testing--which is perfectly fine, but I think it would be useful to note the 1.0v number as well for quick comparison to official IEC testing protocol results. If I had configurable testing equipment, I would also configure it to discharge down to .8v for personal use, but for comparison with official published numbers from manufacturers, I think discharging to 1.0v--or at least reporting the specific number when the cell reaches 1.0v on its way to .8v--would be useful. Thanks again for your work BG.


45/70 said:


> Hi BG. Not getting super technical about it, I find it interesting how the Mahas come very close to the IEC 0.2 discharge info you obtained. My results with my Maha C9000's as I remember anyway, were pretty much spot on with your results for the original eneloops, Sanyo Industrial 2500's. and the Sanyo 2700's. If the Maha's are off, on the discharge results, all I can say, is that they appear to be good enough for my personal use anyway. I'm surprised that they are that close, really. Dave





Battery Guy said:


> Is there a difference? Technically, there should not be any difference, other than the relative accuracy of the Maha and Maccor, and variability between cells. I completely agree Dave. I think that the Maha and Maccor results agree very well. I hope that I was not giving the impression that I thought the Maha is deficient with respect to its accuracy. Indeed, for the price, I am very, very impressed with the Maha C9000. Cheers, BG





*Re: The AA NiMH Performance Test Thread* Written by *45/70* on 01-08-2011 03:35 PM GMT



Battery Guy said:


> I hope that I was not giving the impression that I thought the Maha is deficient with respect to its accuracy. Indeed, for the price, I am very, very impressed with the Maha C9000.


 No problem there, BG. I was just expressing my satisfaction with the C9000's as well. 


LetThereBeLite said:


> ......Well, the Maha discharges to .9v and the IEC specs call for discharges to 1.0v. (I wasn't aware of this difference before. I thought the IEC called for discharging to .9v and that's why Maha discharges to .9v)......


 Hi Let. I'm pretty sure the Maha discharges to 0.9 Volt because it utilizes PWM during discharge, as opposed to constant current. The use of 0.9 Volt with PWM, likely closely approximates a CC discharge to 1.0 Volt. Dave



*Re: The AA NiMH Performance Test Thread* Written by *LetThereBeLite* on 01-08-2011 03:38 PM GMT 



45/70 said:


> Hi Let. I'm pretty sure the Maha discharges to 0.9 Volt because it utilizes PWM during discharge, as opposed to constant current. * The use of 0.9 Volt with PWM, likely closely approximates a CC discharge to 1.0 Volt.* Dave


 Good to know Dave. That's a good point.



*Re: The AA NiMH Performance Test Thread* Written by *Mikl1984* on 01-08-2011 11:54 PM GMT 



LetThereBeLite said:


> Well, the Maha discharges to .9v and the IEC specs call for discharges to 1.0v.


 Not really  IEC discribes 0.2C discharge till 1V ONLY For example 1C till 0.9V, more than 1C till 0.8V



*Re: The AA NiMH Performance Test Thread* Written by *Mikl1984* on 01-08-2011 11:56 PM GMT 



45/70 said:


> I'm pretty sure the Maha discharges to 0.9 Volt because it utilizes PWM during discharge, as opposed to constant current.


 It seems to me you are wrong 



*Re: The AA NiMH Performance Test Thread* Written by *Battery Guy* on 01-09-2011 08:13 AM GMT 



Mikl1984 said:


> Not really  IEC discribes 0.2C discharge till 1V ONLY For example 1C till 0.9V, more than 1C till 0.8V


 Hi Mikl You can discharge a cell to 0.9, 0.8 or even 0.0 V and still be in compliance with the IEC spec, as long as you record the capacity at 1.0 V. Also, at a 0.2C rate, there is very, very little capacity difference between 1.0 V, 0.9 V and 0.8 V. Certainly, for the general hobbyist, this difference is insignificant. The reason that I discharge these cells to 0.8 V is because at the higher drain rates, there can be a significant difference between 1.0, 0.9 and 0.8 V. I am happy to add the IEC discharge curve to these tests, but I think that a detailed discussion of the merits of the IEC, and whether or not the Maha complies with this spec, are too far off topic and deserve their own thread. I would prefer that this thread focus on the performance differences between the cells tested. Cheers, BG



*Re: The AA NiMH Performance Test Thread* Written by *VidPro* on 01-10-2011 01:53 AM GMT

:thanks: i dont care what method you test with, as long as we have an idea of the method (is in the post), and that method is used in similarity for the items compared on the same graph. course it helps if the method chosen also realates in some way to reality. Reality is rarely found in the bottom of a pitri dish  Prolly the worst thing you could do when compiling the data on ONE graph is to change any methodology mid-stream, then add that to the same graph. soo, keep up the great stuff. , in whatever method you desire to report it in. Unless your going to post at the top that you "Are attempting to test using the manufactures recommended pitri dish". the ragnone plot still rots my brain :mecry:, so i might BEG that when you put in the other graphs below it, showing the tests that the Rate is shown somewhere? or is that another New fangled thing that is there i just aint seeing. (no i cant count to 10, i just want to look at the pretty pictures) it really helped when you put in the 3rd graph type too.



*Re: The AA NiMH Performance Test Thread* Written by *45/70* on 01-10-2011 09:37 AM GMT



Mikl1984 said:


> > Originally Posted by *45/70* https://www.candlepowerforums.com/posts/3648200#post3648200
> >
> > I'm pretty sure the Maha discharges to 0.9 Volt because it utilizes PWM during discharge, as opposed to constant current.
> 
> ...


 Wrong? Why? The Maha C-9000 utilizes a 1000mA base current when discharging cells. For lower discharge rates (<1000mA), PWM is utilized. The discharge is then terminated at 0.9 Volt. Dave



*Re: The AA NiMH Performance Test Thread* Written by *Mikl1984* on 01-10-2011 09:55 AM GMT




45/70 said:


> For lower discharge rates (<1000mA), PWM is utilized.


  Wrong again  PWM is used even in 1000mA mode  And coef is 0.91. Maha use non-PWM charge (2A)/discharge(1A) in Service Mode ONLY  BG, sorry for off



*Re: The AA NiMH Performance Test Thread* Written by *Battery Guy* on 01-11-2011 05:29 PM GMT



VidPro said:


> the ragnone plot still rots my brain :mecry:, so i might BEG that when you put in the other graphs below it, showing the tests that the Rate is shown somewhere? or is that another New fangled thing that is there i just aint seeing.


 Hey VidPro I was attempting to keep the constant current curves "clean", which is why I did not label the curves with specific discharge currents. Every attempt that I have made to do so has made them very, very messy. But I am certainly happy and willing to improve them in any way that will make them more useful. What would you suggest? Cheers, BG



*Re: The AA NiMH Performance Test Thread* Written by *VidPro* on 01-11-2011 11:10 PM GMT



Battery Guy said:


> Hey VidPro I was attempting to keep the constant current curves "clean", which is why I did not label the curves with specific discharge currents. Every attempt that I have made to do so has made them very, very messy. But I am certainly happy and willing to improve them in any way that will make them more useful. What would you suggest? Cheers, BG


 i suggest that i learn to count  i agree it would make them more messy, best i can think of is putting cute pointers and baloon statments on the ones that fail miserably, like this <--- see right there at 60Amps it completly fails .  just never seen such Integer based chart, by default it IS clean, but it doesnt have .5A in it.



*Re: The AA NiMH Performance Test Thread* Written by *purduephotog* on 01-14-2011 09:10 AM GMT 



Battery Guy said:


> You may indeed dare. These are non-LSD, correct?


 No, they are the LSD cells. I have only bought the LSD ones after having such bad experiences with other brands.



*Re: The AA NiMH Performance Test Thread* Written by *LoveLearn* on 01-20-2011 09:36 PM GMT

I'd like some help interpreting these excellent cell performance charts. Some loads are generally continuous, even if they vary slightly through time. Regulated and unregulated flashlights are typical of that temporal loading pattern. Some cyclical-pattern loads occur as extended On-&-Off or High-&-Low loading-period series. Examples include portable audio playback and recording devices that present cyclical-pattern loads to their battery/batteries. For instance a motor-driven hard disk or motor-driven CD reader may cycle on and off as the device reads sections of an audio file into volatile memory to sustain a continuous audio playback stream. Those device batteries see a low continuous load which drives the electronics package. On top of that it sees much higher-current brief intermittent loads driving the motor. Both are needed to sustain continuous playback. How should we interpret intermittent cyclical loads as analogs comparable to the continuous curves presented in these very informative charts? Battery-powered devices which present cyclical-pattern loads to batteries are not uncommon. Thoughts? And why do you hold that opinion? Thanks for your consideration, John



*Re: The AA NiMH Performance Test Thread* Written by *Battery Guy* on 01-22-2011 06:28 AM GMT 



LoveLearn said:


> How should we interpret intermittent cyclical loads as analogs comparable to the continuous curves presented in these very informative charts? Battery-powered devices which present cyclical-pattern loads to batteries are not uncommon. Thoughts? And why do you hold that opinion? Thanks for your consideration, John


 I was wondering when someone would bring this up. I can tell you that there is a lot of debate about this issue in the battery testing world, and among battery manufacturers. Essentially the battery performance under any load is related to it's total capacity, the instantaneous internal resistance, and the change in internal resistance under an applied load. The change in internal resistance is a result of the inability of ions to diffuse quickly enough in the cell to keep up the discharge current. The result is that ion concentration gradients build up, resulting in a phenomenon known as concentration overpotential, which is a fancy way of saying that the internal resistance increases. You can see the effect of the concentration overpotential if you stop discharging a cell and measure the voltage as it recovers. As soon as you cut the load on the cell, the voltage jumps up. This initial jump in voltage is a result of the ohmic resistance in the cell. If you monitor the cell over time, you will see that the voltage slowly continues to increase. This slower voltage recovery is a result of the concentration gradients relaxing as the ions diffuse throughout the cell. So, getting back to your question. A continuous discharge test, whether it be constant current, resistance or power, is the most strenuous of tests because no time is given for the concentration gradients to relax within the cell. Therefore, differences between cells will usually be more pronounced with continuous discharge tests compared to intermittent discharge tests. There are some exceptions, and it is possible to make a cell that does better on intermittent discharge but worse on continuous discharge (this is essentially what Panasonic did for the Oxyride cell, which does better than alkalines in pulse power applications like digital cameras, but is not as good for moderate to low power applications); however, it is rarely the case with consumer batteries. Hope this helps, Cheers, BG



*Re: The AA NiMH Performance Test Thread* Written by *popoyaya* on 01-25-2011 01:49 AM GMT

Hi, fascinating thread and very educational though trying to interpret the graphs is somewhat mindboggling. I would just love to know how bright this torch will be using an AAA NiMH? http://www.dealextreme.com/p/waterpr...ht-1-aaa-47661 And would I be right in assuming that Eneloops in particular can output more sustained power, and therefore more light in a power LED torch? Is there an LSD battery that would be brighter?



*Re: The AA NiMH Performance Test Thread* Written by *VidPro* on 01-25-2011 04:43 AM GMT



popoyaya said:


> Hi, fascinating thread and very educational though trying to interpret the graphs is somewhat mindboggling. I would just love to know how bright this torch will be using an AAA NiMH? http://www.dealextreme.com/p/waterpr...ht-1-aaa-47661 And would I be right in assuming that Eneloops in particular can output more sustained power, and therefore more light in a power LED torch? Is there an LSD battery that would be brighter?


 eneloop/duraloop would be best "all around" but there can be other factors. many of the lights like this will vary thier regulation with the voltage. In the first few minutes of a fresh alakine , it could be brighter (barely), then that is done. a lithium cell would hold voltage higher and be a bit brighter and should be in spec for energyser lithium cell item. a li-ion (3.6V) cell item would really crank it up, and possibly overdrive it, from the specs users provided, the extra voltage of a li-ion cell would be ok for short runs. it would not give you runtime , but would probably Direct drive the led into more brightness, as long as you didnt burn out the driver, which would take a lot of time to test if that was occuring. the eneloop would be great for longevity durability cycles, and long term storage with it still usable, BUT many other ni-mhy cells could give you tiny bits more capacity for as long as they hold it , for AAA that isnt long  even the eneloops AAA are not "durable" cell items. i would say for AAA sizes, knowing the batteries capacity on that day, and its ability to hold voltage under a load today, would be what your asking. so anything good, then you knowing/testing which ones are still working great at the time. so whatever you want, there is some Give and Take in a lot of the different variaties and styles, and give and take with output vrses light longevity parked time, and runtimes.



*Re: The AA NiMH Performance Test Thread* Written by *Battery Guy* on 02-08-2011 11:45 AM GMT

New constant current discharge test results added today for the TruCell AA NiMH. The data for the Ragone plot is being collected now and I will post the results by end of week. Special thanks to CPF member TurboBB for sending me two of these cells for testing. Any other recommendations? Cheers, BG



*Re: The AA NiMH Performance Test Thread* Written by *turboBB* on 02-08-2011 12:45 PM GMT 

Hey BG thx for the data! So looking at your charts, looks like these cells perform quite decently and provided the self-discharge holds up, is probably one of the best values for LSD cells (about $1.25 per cell exc. shipping if ordered direct from mfg site). When the deal was on at Sears, a 20 pack was only $15.99 so worked out to .80 each cell exc. shipping. Cheers, Tim



*Re: The AA NiMH Performance Test Thread* Written by *Battery Guy* on 02-08-2011 01:20 PM GMT



turboBB said:


> Hey BG thx for the data! So looking at your charts, looks like these cells perform quite decently and provided the self-discharge holds up, is probably one of the best values for LSD cells (about $1.25 per cell exc. shipping if ordered direct from mfg site). When the deal was on at Sears, a 20 pack was only $15.99 so worked out to .80 each cell exc. shipping. Cheers, Tim


 For the price, they certainly seem to be good performers for low to moderate current applications. I did notice that the wrapper peeled away and exposed the metal can at the seam at some point during the constant current discharge tests. It appears that the cell got sufficiently hot during the high current discharges to cause the wrapper to shrink and pull away from the can. I would want to keep an eye on that if you use these cells in high current devices. Thanks again TurboBB for supplying the cells for testing. Cheers, BG



*Re: The AA NiMH Performance Test Thread* Written by *MorePower* on 02-08-2011 03:17 PM GMT 



Battery Guy said:


> New constant current discharge test results added today for the TruCell AA NiMH. The data for the Ragone plot is being collected now and I will post the results by end of week. Special thanks to CPF member TurboBB for sending me two of these cells for testing. Any other recommendations? Cheers, BG


 Rayovac Platinum? PM if you'd like samples.



*Re: The AA NiMH Performance Test Thread* Written by *Battery Guy* on 02-10-2011 03:05 PM GMT 



MorePower said:


> Rayovac Platinum? PM if you'd like samples.


 Do you mean these? If so, I already have some on order.



*Re: The AA NiMH Performance Test Thread* Written by *MorePower* on 02-11-2011 09:19 AM GMT 



Battery Guy said:


> Do you mean these? If so, I already have some on order.


 Those are the ones.



*Re: The AA NiMH Performance Test Thread* Written by *Battery Guy* on 02-11-2011 05:37 PM GMT 



MorePower said:


> Those are the ones.


 You got it MorePower. I should be able to post the results by the middle of next week. Also, I have heard some good reports on Tenergy LSD AA NiMH cells so I hope to try those soon. Cheers, BG



*Re: The AA NiMH Performance Test Thread* Written by *Battery Guy* on Yesterday 11:45 AM GMT 

Greetings Everyone, I have added discharge plots for the Rayovac Platinum cells. In addition, I added a new plot: Energy loss as a function of discharge current. The energy is lost in the form of heat, so the higher the energy loss, the hotter the cell will get during discharge. I find this plot interesting because it seems like the data is clustered into three groups, with the highest energy loss associated with the Sanyo 2500, Sanyo 2700 and the Imedion 2400 cells. The lowest energy loss is found in the Elite 1700, of course. The new Tenergy 2300 LSD cells were just put on test today, so expect results early next week. Cheers, BG



*Re: The AA NiMH Performance Test Thread* Written by *Russel* on Yesterday 12:54 PM GMT 

Battey Guy, how do you determine the energy loss in the form of heat as a function of discharge current? Is the heat measured directly or calculated from the discharge test results. Nice graphs by the way.



*Re: The AA NiMH Performance Test Thread* Written by *Battery Guy* on Unknown 



Russel said:


> Battey Guy, how do you determine the energy loss in the form of heat as a function of discharge current? Is the heat measured directly or calculated from the discharge test results. Nice graphs by the way.


 It's quite simple actually. I know the total energy available because I do a low rate discharge. The difference between the total energy and the discharge energy (area under the voltage v capacity discharge curves) is the energy loss. Doing the calculation in this way is actually only an estimate, because it assumes that all of the capacity has been utilized. This assumption gets worse as the discharge rate increases, so at the highest discharge rates, the energy loss that I plot is a slight over estimate. However, I think that it is a good enough estimate for our purposes. Cheers, BG



*Re: The AA NiMH Performance Test Thread* Written by *Russel* on Unknown 

So the estimation is derived mathematically, that makes sense. It is surprising how the Elite 1700 stands out so much. The last three plots (Discharge Energy (Wh), Energy Efficiency (%), and Energy Loss as Heat (Wh) vs Discharge Current (A)) really show the effect of internal resistance. Thanks for the plots and the explanation!



*Re: The AA NiMH Performance Test Thread*
Written by *Battery Guy* on 02-19-2011 12:19 PM GMT




Originally Posted by *Russel* 
So the estimation is derived mathematically, 
that makes sense. It is surprising how the Elite 1700 stands out so 
much. The last three plots (Discharge Energy (Wh), Energy Efficiency 
(%), and Energy Loss as Heat (Wh) vs Discharge Current (A)) really show 
the effect of internal resistance.



Yes, the Elite 1700 is really quite different from the other NiMH
cells, and it does have spectacular high rate performance. I only wish
that someone would make an LSD cell that had similar performance 
characteristics. The big problem with the Elite 1700 is a high 
self-discharge, and relatively high self-discharge rate variability from
cell-to-cell. This means that you need to "rebalance" a multi-cell 
pack relatively relatively frequently by charging at a low rate. Yes, the Elite 1700 is really quite different from the other NiMH
cells, and it does have spectacular high rate performance. I only wish
that someone would make an LSD cell that had similar performance 
characteristics. The big problem with the Elite 1700 is a high 
self-discharge, and relatively high self-discharge rate variability from
cell-to-cell. This means that you need to "rebalance" a multi-cell 
pack relatively relatively frequently by charging at a low rate.

*Re: The AA NiMH Performance Test Thread*
Written by *Battery Guy* on 02-21-2011 08:19 AM GMT

Discharge curves have been added for the Tenergy 2300 LSD AA cell. 
I had high hopes for this cell based on a couple posts in other 
threads, but its performance really let me down. The IEC discharge 
capacity was only 1.98 Ah, and the cell has substantial voltage sag at 
higher currents.

From an "out of the package" performance perspective, this cell is 
definitely worst in class, at least for the LSD cells I have tested so 
far.

*Re: The AA NiMH Performance Test Thread*
Written by *InHisName* on Yesterday 04:25 AM GMT

Great new plots! Battery Guy

Two of them really show differences in that I kept seeing Eneloopxx, 
TruCell, Energizer2300, and Eneloops all coming in "2nd" to the 1700.

Since I have plenty of cells I'll probably only jump if any one has 
bargain offerings somewhere. I wouldn't mind trying 4 or 8 if I 

*Re: The AA NiMH Performance Test Thread*
Written by *080* on Yesterday 06:47 PM GMT

Hello, anyone ever tested or have experience with the AA*turnigy* low self discharge (not tenergy) 

battery from HobbyKing. They are 2200mah and consistently charge to 
2350mah. Any data knowledge appreciated especially for use in torches.

*Re: The AA NiMH Performance Test Thread*
Written by *Mr Happy* on Yesterday 07:59 PM GMT




Originally Posted by *080* 
Hello, anyone ever tested or have experience with the AA *turnigy* low self discharge (not tenergy) 

battery from HobbyKing. They are 2200mah and consistently charge to 
2350mah. Any data knowledge appreciated especially for use in torches.



There are two kinds of battery in the world: there are Eneloops 
and there is everything else. The Turnigy batteries are not Eneloops... 

discovered approx $1 per cell.


Above are all cached posts from November 2 2010 through to the end of February 2011.
This represents original posts sequentially from #14-95.
No information was lost in this thread when the lights went out at CPF.

A special thank you to InHisName for finding posts 91-95.:thumbsup:


----------



## Battery Guy (Mar 26, 2011)

Thanks Jam(me)s! That is really great!


----------



## ALW248 (Jul 30, 2011)

Thanks!

So high power AA rechargeable batteries:
Sanyo Eneloop NiMH LSD
Elite NiMH
PowerGenix NiZn

Anything else?

The OEM of Elite must also sell to brands other than Elite, right?

Can good NiCd outputs more power?


----------



## LuxLuthor (Aug 8, 2011)

WOW, what a most excellent thread. I love the diversity of your graphs, and what they show. I saved a complete offline copy of this with my Firefox Scrapbook plugin for offline viewing. Thanks for all the enormous time and detail work to get useful displays all together. Big thanks to James also for all those rescued posts.

*Well deserved to be listed in the pinned Threads of Interest !!!!!!!!!*


----------



## Battery Guy (Aug 8, 2011)

ALW248 said:


> Thanks!
> 
> So high power AA rechargeable batteries:
> Sanyo Eneloop NiMH LSD
> ...



Apparently the Elite 1700s are no longer available. The manufacturer made a change to the cells that resulted in a decrease in performance. However, I just ordered the new Elite 2000 AA cells, and hope to have those tested this week.

Although the PowerGenix can provide a lot of power, these cells are inconsistent and tend to be unreliable. Also, PowerGenix is out of the AA business, so there is no good reason to invest in these cells if you haven't done so already.



ALW248 said:


> The OEM of Elite must also sell to brands other than Elite, right?



One would think so, but perhaps not as loose cells.



ALW248 said:


> Can good NiCd outputs more power?



You might find a high power NiCd that is better than the eneloop, but I have not seen anything that can compete with the Elite 1700s. But you will sacrifice a lot of capacity by going to a NiCd.

Cheers,
BG


----------



## Battery Guy (Aug 8, 2011)

LuxLuthor said:


> WOW, what a most excellent thread. I love the diversity of your graphs, and what they show. I saved a complete offline copy of this with my Firefox Scrapbook plugin for offline viewing. Thanks for all the enormous time and detail work to get useful displays all together. Big thanks to James also for all those rescued posts.
> 
> *Well deserved to be listed in the pinned Threads of Interest !!!!!!!!!*


 
Thanks Lux! Much appreciated.

I hope to have the new Elite 2000s added by the end of the week.


----------



## ALW248 (Aug 9, 2011)

Battery Guy said:


> Apparently the Elite 1700s are no longer available. The manufacturer made a change to the cells that resulted in a decrease in performance. However, I just ordered the new Elite 2000 AA cells, and hope to have those tested this week.
> 
> You might find a high power NiCd that is better than the eneloop, but I have not seen anything that can compete with the Elite 1700s. But you will sacrifice a lot of capacity by going to a NiCd.


 
If a good NiCd can also last more years than Eneloop, then NiCd can be used in applications that short run time can be tolerated.

Eneloop Lite is also interesting, if it can output more power, and last more years, than 2Ah Eneloop.

Looking forward to your testing of the new Elite.

Thanks a lot!


----------



## LuxLuthor (Aug 10, 2011)

BG, I remember Mike @ CBP telling me that the "Elite" brand is his brand. I have never heard of whoever is making them (in China) for him rebranding the same cells under another name. Not sure outside of RC and Flashlight nuts who would need such a high amp output, and be willing to put up with the (relatively) fast self-discharge rate as a downside. Most RC have switched over to a "safe" lithium ion chemistry.


----------



## jd_oc (Aug 19, 2011)

Battery Guy said:


> Thanks Lux! Much appreciated.
> 
> I hope to have the new Elite 2000s added by the end of the week.


 
Really looking forward to the new tests on the Elite 2000s. Have they come in yet?


----------



## Battery Guy (Aug 25, 2011)

jd_oc said:


> Really looking forward to the new tests on the Elite 2000s. Have they come in yet?


 
They did come in, but only a few days before I had to leave town for a couple weeks. I am still traveling, but plan to test them when I return in a week.

Cheers,
BG


----------



## jd_oc (Sep 11, 2011)

Thanks for the update. Hope you had a good vacation. Looking forward to the new tests.


----------



## Battery Guy (Sep 11, 2011)

jd_oc said:


> Thanks for the update. Hope you had a good vacation. Looking forward to the new tests.


 
I am looking forward to the test results too! Unfortunately, I have been slammed at work since returning from my travels (I wouldn't exactly call it a vacation). I hope to get these on test by the end of the week.


----------



## lightseeker2009 (Sep 12, 2011)

Have nobody ever tested and compared a Turnigy 2200mah LSD AA to other AA's?
I bought a few of them and they compare very good to very popular batteries. Very unscientifically but still, I've compared the Turnigy to an Eneloop and an Energizer 2000. I connected it to a LED and surprise surprise, the Turnigy did deliver a bit more power to the LED than the Eneloop...
I have fully charged some Eneloops and Turnigys and will leave them in my safe for 6 months. I want to see just what will be the difference between the two after 6 months. With one set I want to see exactly how long it will take my Maha 8008 to charge them to full capacity.
Now its just for the 6 months to pass.


----------



## Battery Guy (Sep 12, 2011)

lightseeker2009 said:


> Have nobody ever tested and compared a Turnigy 2200mah LSD AA to other AA's?



I have not tested these yet, but can add them to the list. I am especially interested in any cell that appears to deliver more "power" (i.e. lower internal resistance) than eneloops.


----------



## lightseeker2009 (Sep 12, 2011)

I will post some links from rcgroups.com tomorrow when I'm back at work. The batteries were tested and found to exceed expectations. They all tested a real world 2200+mah. Its strange that they are not more popular then they are. I would love to see them included in your tests


----------



## 45/70 (Sep 12, 2011)

lightseeker2009 said:


> ......The batteries were tested and found to exceed expectations. They all tested a real world 2200+mah. Its strange that they are not more popular then they are......



I have no experience with the Turnigy cells, but in the past some of the Chinese LSD cells have been tested and initially shown slightly higher capacity than eneloops. I'm not sure they were able to rival the enloopps as far as holding voltage under load (Power), however. Anyway, after some cycling these cells lost any advantage they initially had over the eneloops, as well as loosing some of their LSD capability, as well. I too will be curious to see how well these Turnigy cells perform.

Dave


----------



## lightseeker2009 (Sep 14, 2011)

lightseeker2009 said:


> I will post some links from rcgroups.com tomorrow when I'm back at work. The batteries were tested and found to exceed expectations. They all tested a real world 2200+mah. Its strange that they are not more popular then they are. I would love to see them included in your tests


 
Here is a quote from one of the tests done. This capacity test was done at a 4A discharge level. 
''And the update with discharge @4A:

Discharged:
LSD: 1966mAh (89,4% of nominal capacity)
Eneloop: 1602mAh (80,1% of nominal capacity)


Difference in discharged capacity between LSD and Eneloop:
2A: 296mAh (+16,3%)
3A: 341mAh (+19,9%)
4A: 364mAh (+22,7%)

With higher current the LSD has much more usable capacity!''

So I look forward to any test done with these Turnigy AA's


----------



## 45/70 (Sep 14, 2011)

Those are impressive results, lightseeker. As I mentioned earlier though, Chinese cells such as the Turnigy's haven't, in the past anyway, been able to hold up after cycling as well as eneloops.

Can you post a link to the thread?

Dave


----------



## lightseeker2009 (Sep 14, 2011)

Here you go
http://www.rcgroups.com/forums/showthread.php?t=1185588&page=2


----------



## 45/70 (Sep 14, 2011)

lightseeker2009 said:


> Here you go
> http://www.rcgroups.com/forums/showthread.php?t=1185588&page=2



Thanks for the link, light.

There seems to be some conflict as to how good these cells really are, earlier in the thread. Add to that the thread died over a year ago with no word as to how well the cells actually held up as far as self discharge, so personally, I can't get too excited about them. It still would be interesting to see more information about these cells though, you never know, until a cell is well vetted through various types of testing.

Dave


----------



## lightseeker2009 (Sep 15, 2011)

Agreed. That is way I mentioned them. I would love to see them tested by one of this sites experienched users. I feel they are good. I have quite a lot of them in various applications and so far, I have no complaints.


----------



## Mikl1984 (Sep 15, 2011)

This is comparison graphs Turnigy and Eneloop after 62 days storage http://forum.ixbt.com/topic.cgi?id=42:20764-76#2415
According those data Turnigy is more LSD than Eneloop


----------



## lightseeker2009 (Sep 15, 2011)

Mikl1984 said:


> This is comparison graphs Turnigy and Eneloop after 62 days storage http://forum.ixbt.com/topic.cgi?id=42:20764-76#2415
> According those data Turnigy is more LSD than Eneloop


 
Thanks for the link but help me to read it in English please. I cant even get google translate to fix it for me.


----------



## 45/70 (Sep 15, 2011)

lightseeker2009 said:


> Thanks for the link but help me to read it in English please. I cant even get google translate to fix it for me.



Hi light. Just look at the links in the third post Mikl linked to. It says the cells were discharged at 2A down to 0.9V. That's all you really need to know.

As I said earlier, in the past enloops have shown that they are capable of holding voltage better under load than the Chinese version(s) LSD cells. This is shown in the second graph, as the eneloop holds a slight edge in this regard. Also, as I said before, any capacity advantage these type cells have demonstrated under moderate loads in past tests, is likely lost after cycling 25 times or so and/or 3-6 months of actual use.

I'm not suggesting that these may not be good cells, they _are_ likely better than "traditional" NiMh cells, but in the long run eneloops have always been shown to be a better option, at least for medium to high current drain applications. For low current drain applications, these cells may have some advantage.

Dave

Edit to add, you might want to check out one of the links to the right in that thread. there's a really nice picture of a, er, um, cat.


----------



## lightseeker2009 (Sep 15, 2011)

45/70 said:


> Edit to add, you might want to check out one of the links to the right in that thread. there's a really nice picture of a, er, um, cat.


 
Very very nice kitty What were we talkin about again


----------



## syncytial (Sep 16, 2011)

lightseeker2009 said:


> Thanks for the link but help me to read it in English please. I cant even get google translate to fix it for me.



While Google Translate won't do the page with a single click, a little cut & paste of the Russian text in the post gives...

"Maybe you are interested in the comparison "Turnigy NiMH, 2200 LSD" and "Eneloop Sanyo 3HR-UTGA, 1.2V, 1900 MAh" after two months (62 days) storage at room temperature. Discharging current of 2 amperes to 0.9 volts, followed by a gradual decrease in current at constant voltage."

The graphs are the key.


- Syncytial.


----------



## Sci Fii (Oct 12, 2011)

Battery Guy said:


> I am looking forward to the test results too! Unfortunately, I have been slammed at work since returning from my travels (I wouldn't exactly call it a vacation). I hope to get these on test by the end of the week.



Battery Guy,

Thanks for all you do. Your work is amazing. I see you hope to test the new Elite 2000 AA's. I remember from one of your posts elsewhere you mentioned the old Elite 1700's (maybe 1500's) had an interesting characteristic in that they had a lower initial voltage on start-up. I believe you posted a graph showing the first five seconds of run-time. If possible, might you be able to do a similar test on the new batteries. I like to play around with cheap incandescent's that use 4 AA's and these batteries seem like they would be ideal. Also, could you possibly tell me where to buy these batteries. I've searched and can only find the old 4/5 AA's. Thanks again for all your work.


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## Battery Guy (Oct 13, 2011)

Greetings Everyone

The much anticipated results for the new Elite 2000s have been added to the first post. My apologies for taking so long to get this done. My "real" work life has been quite hectic and has been taking up most of my free time.

One thing that I should point out with the new Elite 2000s is that they do NOT work in a C9000. The positive terminal appears to be too large and does not protrude enough from the crimp area to make contact. Otherwise, they perform very well. I have been using 12 of these in a 64623 for a few weeks and they are doing a great job. Although, the voltage sag on these new Elite 2000 cells appears to be slightly more than the original Elite 1700 cells.

Cheers,
BG


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## ALW248 (Oct 15, 2011)

Thanks a lot!

Too bad that Elite 2000 does not have standard positive terminal.

I am interested in anything that have high voltage at 1A output, even if the capacity is smaller than 1Ah.


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## 45/70 (Oct 15, 2011)

ALW248 said:


> I am interested in anything that have high voltage at 1A output, even if the capacity is smaller than 1Ah.



At a mere 1A, I would think that eneloops would do a decent job. The Elite cells really don't have all that much of an advantage until you get up to 2+ Amps. Of course, if you absolutely need the extra voltage, the Elites will supply a bit higher voltage, at low discharge rates.

Dave


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## Sci Fii (Oct 16, 2011)

ALW248 said:


> Thanks a lot!
> 
> Too bad that Elite 2000 does not have standard positive terminal.
> 
> I am interested in anything that have high voltage at 1A output, even if the capacity is smaller than 1Ah.



Could you please explain what you mean by "does not standard positive terminal"? I have no experience with these cells. Would they not work with some lights? Thanks.


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## Stephen Wallace (Oct 17, 2011)

Sci Fii said:


> Could you please explain what you mean by "does not standard positive terminal"? I have no experience with these cells. Would they not work with some lights? Thanks.



As per Battery Guy's description below: -



Battery Guy said:


> One thing that I should point out with the new Elite 2000s is that they do NOT work in a C9000. The positive terminal appears to be too large and does not protrude enough from the crimp area to make contact.



Basically, while you have a defined button - unlike some flat top li-ion cells - it is wide and very, very shallow, unlike the small protruding buttons you find on the majority of disposable or rechargeable AA cells. Despite the button, it is so shallow, they may as well be flat top cells. 

This can cause issues with some lights. For instance, some lights have a very simple, mechanical method of reverse polarity protection. There is a non conducting ring around the positive contact. This ring is shallow enough for the normal positive contact on a button top cell to reach through, but the flat negative base of the cell is prevented from touching the lights positive contact by the ring. Obviously, if the button head isn't long enough, this physical barrier will also prevent the positive end of the battery touching the lights positive contact.


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## Battery Guy (Oct 18, 2011)

Sci Fii said:


> Battery Guy,
> 
> Thanks for all you do. Your work is amazing. I see you hope to test the new Elite 2000 AA's. I remember from one of your posts elsewhere you mentioned the old Elite 1700's (maybe 1500's) had an interesting characteristic in that they had a lower initial voltage on start-up. I believe you posted a graph showing the first five seconds of run-time. If possible, might you be able to do a similar test on the new batteries. I like to play around with cheap incandescent's that use 4 AA's and these batteries seem like they would be ideal. Also, could you possibly tell me where to buy these batteries. I've searched and can only find the old 4/5 AA's. Thanks again for all your work.



I am really glad that you find the data useful.

With respect to the initial voltage, I think that you must be referring to this thread, where I plotted the voltage during the first 5 seconds of discharge for various discharge currents. I might be able to plot similar data for these cells, but I need to go back to the original data files to see if I collected the data with a sufficiently high sampling rate.

My understanding is that the "Elite" cells are the private label brand for CheapBatteryPacks.com.

Cheers!
BG


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## Sci Fii (Oct 18, 2011)

Stephen Wallace,

Thanks for taking the time to give a thorough explanation to a newb. I clearly understand what you are saying. I think I should be OK after looking at my lights but I'll never know until I actually test them. I was going to order several sets of four for my 4AA lights but instead I just placed an order for one set. If they work for my purposes I'll order more later. Thanks again.


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## ALW248 (Oct 18, 2011)

Not only your light, the battery needs to work in your charger, too.


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## Sci Fii (Oct 18, 2011)

Battery Guy,

Indeed, I find the data not only useful but also interesting. While I don't have any connection to science in my job, I've always enjoyed the field. 

The link you referenced in your post is the one I was referring to. The delta between start-up and constant voltage was interesting. Seems like a rather nice quality for incandescent flashlights. I see they are basically flat tops and I've never used those before. I ordered a set to see if the flat top will be something I can work with. BTW, I know this an NIMH thread, but I've recently taken an interest in LifePO4 cells. Do you ever do any testing on those?


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## Sci Fii (Oct 18, 2011)

ALW248 said:


> Not only your light, the battery needs to work in your charger, too.



Yes, this may be an issue but for a short term solution I have one of those universal chargers I can use in a pinch. I need to get a real charger so this may be a reason to do so.


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## cad3 (Dec 6, 2011)

Thanks BG! 

This was exactly what I was looking for! 
I think of myself as a smart guy but reading this stuff just makes me feel like a neophyte. I see all the charts but I'm still a little confused.

You said that you liked the Elite 1700 and the Eneloop XX for that they provide/produce respectively.

Would you please elaborate? I'm guessing that one provides high power for shorter time period or... meh, I'm just confused.

I've been thinking about getting a number of Eneloops to just handle various remotes at home (plus wii remotes).

I also have a Canon 580 EXII camera flash. I was thinking about the Eneloop XX for that but was not sure the cost / value / performance was there. Your thoughts? Anyone elses thoughts?

Thanks!

-C


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## Wrend (Dec 6, 2011)

In regards to XX Eneloops and the regular "1500" cycle 2000mAh ones, I think the regular ones are the better deal over all since they have 2.4x the cumulative lifetime capacity expectancy, while the XX cells only have 1.25x capacity per charge. The regular Eneloops also cost about half as much, so definitely the better value for general use, in my opinion.

The main reason to get the XX cells is if for whatever reason you really need that little bit extra run time. :shrug:

I always keep my Eneloops charged and I have extra sets so I can just switch them out whenever I need to without having to wait for them to charge.


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## cad3 (Dec 13, 2011)

Wrend said:


> In regards to XX Eneloops and the regular "1500" cycle 2000mAh ones, I think the regular ones are the better deal over all since they have 2.4x the cumulative lifetime capacity expectancy, while the XX cells only have 1.25x capacity per charge. The regular Eneloops also cost about half as much, so definitely the better value for general use, in my opinion.
> 
> The main reason to get the XX cells is if for whatever reason you really need that little bit extra run time. :shrug:
> 
> I always keep my Eneloops charged and I have extra sets so I can just switch them out whenever I need to without having to wait for them to charge.



Thanks for that! I have been price watching for a while, in the hopes that they would go on sale (kinda getting the feeling that isn't going to happen). Current plan is to take the plunge and get the MH-C9000 charger and 16-20 AA Eneloop ("1500"s) and 8 AAA. I like that they have spacers for C and D cells. I can't think of anything I use that would need them but it's a nifty option.


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## Battery Guy (Dec 13, 2011)

cad3 said:


> Thanks BG!
> 
> This was exactly what I was looking for!
> I think of myself as a smart guy but reading this stuff just makes me feel like a neophyte. I see all the charts but I'm still a little confused.
> ...



Well, the Elite 1700s are no longer available. So those plots are a bit out of date. However, you can now get the Elite 2000 cells from cheapbatterypacks.com.

But unless you need really high current (probably 3 amps or more), you are almost certainly better off with the eneloops. The Elite cells are really only worthwhile if the application calls for very high currents. The Elite 2000 are not LSD (low self discharge) and likely do not have near the cycle life of the eneloops. I am presently using the Elite 2000s in a 64623 hotwire mod and they work great, but that bulb pulls 10 amps.

For remotes, you are much, much, much better off going with the eneloops. In fact, don't even consider using the Elites for that application.

Hope this helps.

Cheers,
BG


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## ALW248 (Dec 29, 2011)

cad3 said:


> I've been thinking about getting a number of Eneloops to just handle various remotes at home (plus wii remotes).
> 
> I also have a Canon 580 EXII camera flash. I was thinking about the Eneloop XX for that but was not sure the cost / value / performance was there. Your thoughts? Anyone elses thoughts?



For camera flash, if you use it everyday, use something like Elite if the contacts work. The high voltage at high current output would enable the flash recharge faster.

If a full charge is not enough for a single session, if you want to minimize battery change, maybe XX can eliminate the change, or reduce 2 changes to 1.

Otherwise, use Eneloop.

For remotes that do not use a lot of power, you can use the cheapest batteries, as long as they do not leak. Rechargeable less than $1 would work. Even if the batteries develop high impedance or lose capacity, they would still work very well in remotes for years. You don't need Eneloop for those.


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## jgbedford (Dec 29, 2011)

Wonderful information BG!

I see the Enloops are getting a lot more chatter than the Imedions - why is that?

If I'm reading your results correctly, the Imedions carry higher capacity?

I'm looking for a cost effective way to keep my Canon 580 exII flash going, and want to keep spares in my camera bag - but don't shoot enough requiring me to recycle the batteries through the charger every few weeks.

Confused 


JB


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## Mr Happy (Dec 30, 2011)

jgbedford said:


> Wonderful information BG!
> 
> I see the Enloops are getting a lot more chatter than the Imedions - why is that?
> 
> ...



Eneloops have an established record of quality, consistency, durability and performance. When you depend on batteries to work reliably then simple capacity is not the only thing that counts. Immedions may be good also, but there is less experience with those and Eneloops have set the standard that others have to follow.


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## ALW248 (Jan 1, 2012)

cad3 said:


> I have been price watching for a while, in the hopes that they would go on sale (kinda getting the feeling that isn't going to happen).



Or for the same price, you might want to wait for the new and better HR-3UTGB.

And after the new one is widely available, maybe the 2 generations old HR-3UTG will go on clearance.

For low power devices like remotes, Eneloop Lite might be better, if it is significantly less expensive than 2AH Eneloop.


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## Wrend (Jan 1, 2012)

Even in something that uses that low of an average current rate, I think the capacity will still get used up faster doing useful work than it would from self discharging.

For the Lites to be worth it (at least in cumulative lifetime capacity potential) they would need to be less than 2/3 the cost of the "1500" cycle ones. Even if that is the case, with twice the capacity the "1500" cycle ones are probably worth it just for the convenience of not having to switch out the cells as often.

Given the capabilities of the "1500" cycle cells, the XX cells are way overpriced, in my opinion. Even if they were the same price, I still think the "1500" cycle cells are the better value. If the "1800" cycle cells are the same price as the "1500," then they'll be the new best deal.


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## Battery Guy (Jan 3, 2012)

jgbedford said:


> Wonderful information BG!
> 
> I see the Enloops are getting a lot more chatter than the Imedions - why is that?
> 
> ...



Hi JB

The Imedions have relatively high internal resistance, which results in a lower operating voltage under load. You can see this in the constant current discharge curves. This will result in lower brightness for direct drive flashlights where the bulb or LED brightness is directly dependent upon the voltage of the battery.

For a flash such as your Canon 580 exII, the lower internal resistance of the Eneloop should result in faster flash recharge rates. If the flash pulls a constant power pulse from the battery, you might even get more flashes from the Eneloop because the flash will pull more current from the Imedions to achieve the same power (power = voltage x current). But if you use the flash infrequently and/or don't take flash photos in rapid succession, then the Imedions will probably be just fine.

The Eneloops have a great track record and are known to have a fantastic cycle life, whereas this has not been established for the Imedions, or really any other LSD to my knowledge.

For best ultimate performance in a flash, the Eneloop XX (aka Eneloop Pro) are probably your best choice, but they are expensive. 

Hope this helps.

Cheers,
BG


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## ALW248 (Feb 11, 2012)

Wrend said:


> Even in something that uses that low of an average current rate, I think the capacity will still get used up faster doing useful work than it would from self discharging.
> 
> For the Lites to be worth it (at least in cumulative lifetime capacity potential) they would need to be less than 2/3 the cost of the "1500" cycle ones. Even if that is the case, with twice the capacity the "1500" cycle ones are probably worth it just for the convenience of not having to switch out the cells as often.
> 
> Given the capabilities of the "1500" cycle cells, the XX cells are way overpriced, in my opinion. Even if they were the same price, I still think the "1500" cycle cells are the better value. If the "1800" cycle cells are the same price as the "1500," then they'll be the new best deal.



For my remotes, 2Ah Eneloop would last many years on a single charge. I want to cycle them much more frequently than that. 

Even 1Ah Eneloop Lite would last years.

My damaged NiMH, with decreased capacity and increased impedance, last many months in remotes on a single charge.

For applications need more power, I prefer 2.5Ah XX over 2Ah Eneloop.

Although 2Ah is more than enough for a single session, the higher voltage output of XX at 1Ah discharge point is useful.


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## okc_car_dude (Apr 10, 2012)

Hello Everyone! Kind of a newbie here, but definitely an enthusiast! I've been doing research on Li-ion/polymer, LifePO/4, Ni-Zn, Ni-MH, and Ni-Cd technologies. I've studied a lot and jumped around a lot to obtain my information, so forgive me if I can't exactly recall what came from where... =/

That out of the way!...



Battery Guy said:


> *PowerGenix NiZn*: Tested fresh out of the package. Please note that the voltage axis is scaled differently than the other comparisons.



I'm very curious about the Ni-Zn technology, since it appears to be such a great and safe replacement for many Ni-Cd/Ni-MH packs, where Li-ion would not provide a close enough voltage in terms of toy RC's. (I've been making packs for my son's and niece's cars that allow you to remove individual cells to charge them on a standard charger and be able to balance [albeit by manual voltage readings, lol] each cell).

I also bought some extra's for his mom's Sony camera. Since I've personally used it with alkalines and know of it's voltage shut off tech, I figured she'd get much more use and faster recycle times with the Ni-Zn tech... but here are my Concerns...

I recently contacted PowerGenix, since I've seen on different sites, about the periodic "Maintenance Charge." I've seen different stuff about this. Some says monthly, some every other month, some to not let it drop below 1.68v in storage... So I asked them about it and, after an initial charge, if I just so happened to store a cell for months before use, how would effect the performance/life, etc. of the battery... This is what they told me.



[email protected] said:


> Thank you for your inquiry. Optimum cycle life will be achieved by limiting the individual cell voltage at 1.1 Volts (or greater) at end of discharge. Failure to do so will likely result in deep discharge of some batteries, often resulting in polarity reversal, which is detrimental to overall yield of usable cycles. The batteries should also never be stored at a fully discharged state, and should always be charged using only manufacturer approved NiZn chargers.
> 
> I am not aware of any "monthly maintenance" requirement, but the NiZn batteries will perform better when they are charged more frequently than not, in other words, they do not like to be fully drained before charging.
> 
> ...



So, knowing this and that someone else on this forum I believe, that tested the cells at rates of something like, 1A, 2A, 5A, 10A, 20A (May be missing one)... They seemed to test fine at 10A, but he killed the cell when trying to test for 20A, even though I originally read they should be safe up to rates of 50C. Lol, sorry... I'm a data nerd. My point is the Ni-Zn curves look less consistant after the 1st 6 or so cycles and *I was wondering if they were held to the same 0.8v discharge cutt-off of the Ni-MH? *I'm sure this a request among many and I'm so sorry to trouble you, but I'm just wondering if this is what to expect from the Ni-Zn at higher amperage rates, or if they cell's capacity and discharge characteristics were diminished by over-discharge?

Any info [and especially a retest with a fresh cell and a higher voltage cutt-off  ] would be greatly appreciated!

Joe


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## Marc999 (Jul 9, 2012)

I have 1st and 2nd generation eneloops; all with the exception of 1 or 2 are still reaching their 1900 mAh minimum rating. 

I also have 4 Sanyo XX about 1.5 years old. None of these batteries have ever reached the minimum 2400 mAh. Even 2 Break-ins recently didn't achieve the minimum spec. One Break-in round included a 500 ma discharge, 2300 set capacity. The other Break-in round included a 100 ma discharge, 2400 set capacity. The lowered discharge rate didn't seem to make a difference at all in helping to squeeze out most of the juice prior to Break-in. They range from 2250 to 2333. Yes, not far from the minimum spec., yet still.....

So, from my limited experience with the lovely XX's, I'd say the 1st and 2nd generation regular eneloops have faired better.


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## 45/70 (Jul 9, 2012)

Hi Marc. I'm curious about a couple things. First, how did you "break in" the XX cells? Normally, a break in for 2300mAh cells would involve a 16hr charge at 230mA charge rate, rest 1hr, and then the cell(s) would be discharged at a 0.2C rate (460mA) to 0.90-1.00 Volt (depending on method of discharge, constant current, 1.00 Volt, pulsed current, eg. Maha C9000, 0.90 Volt) to determine cell capacity. The same goes for 2400mAh, only the figures would be 16hr charge at 240mA, 1hr rest, and discharged at 0.2C (480mA) until discharged (again, to 0.90-1.00 Volt/cell). I'm not questioning your results, just what equipment you used for charging/discharging and precisely how you went about the break in process.

Also, any idea how many cycles, full or partial, were on these cells? Were the cells ever potentially deeply discharged, or reverse charged during use? Also, any other factors that may have increased cell degradation, such as high heat, extremely high current use, etc?

I'm not too surprised that the XX cells are not holding up as well as regular eneloops. That's pretty much a given. As with all "high cap" NiMH cells, there have been compromises involved in order to add the additional capacity. I do find it a bit odd though that the XX cells fell short of 2400mAh initially (when new) though. If the XX cells tested 2250-2233mAh after a year and a half, although maybe a bit low, that's about what I might expect.

I'll add here that I have resisted buying any XX cells, so far anyway. Considering the additional cost and expected shorter life cycle, I really have no need for the additional capacity. I thought about maybe just buying four cells, as you apparently did, just to try them out. But this way, you did it for me! I still may have to try some. For the past year or so though, I've been using mostly Li-Ion cells, and have drifted away from NiMH in general. I'm sure I'll be back though!

Dave


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## Yamabushi (Jul 9, 2012)

I took 8 Sanyo XXs new from the package and ran a Refresh on a Maha C9000 (Charge @ 1000 mA / Discharge @ 1000 mA): 2422, 2455, 2436, 2414, 2417, 2449, 2450, 2423 mAh.

Partially depleted them by use in a Fenix TK41 over 3 months and ran another refresh at the same Charge / Discharge rates: 2462, 2460, 2423, 2420, 2439, 2451, 2435, 2442 mAh.


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## CaptCarrot (Aug 24, 2013)

Sorry to dig up an old thread, but I was linked here from a more recent thread.

I know they are not rechargeable, but would it be possible to show a graph that compares Energizer Lithium's a against the Eneloop's at the different discharge rates.

Cheers.


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## HKJ (Aug 24, 2013)

CaptCarrot said:


> Sorry to dig up an old thread, but I was linked here from a more recent thread.
> 
> I know they are not rechargeable, but would it be possible to show a graph that compares Energizer Lithium's a against the Eneloop's at the different discharge rates.



You could check my Comparison of AA chemistries.


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## CaptCarrot (Aug 24, 2013)

Sorry, missed that.


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## HKJ (Aug 24, 2013)

CaptCarrot said:


> Sorry, missed that.



It is a bit difficult to find a specific thread. It would require somebody very dedicated to make an index of interesting threads.


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## Battery Guy (Aug 28, 2013)

You could also check out the old Introduction to Ragone Plots thread. The Energizer Ultimate Lithium and Eneloop curves intersect at a constant power discharge of 2.5 W, or approximately a 1.2C discharge rate. So you get more total energy from the lithium cells for discharge rates less than about 1C (one hour), and more total energy from the Eneloops for discharge rates greater than about 1C. That's not really the whole story, but it is a decent rule of thumb to follow if maximizing runtime is your critical performance metric.

Cheers,
BG


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## vestureofblood (Mar 14, 2014)

Great thread. Thank you for doing this.


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## cj0 (Jan 19, 2017)

Regarding the energy efficiency graph, that reads at discharge rates of 1.0A the energy [Wh] efficiency for each battery is within 90-95%:


>



When I have read correctly the batteries are discharged till 0.8V (my guess: voltage is measured under load, not during rest). Especially for this relative deep discharging, and 10mV -dV charging, I wonder how this leads to efficiencies over 90%.

I have used a SkyRC MC3000 HW>=1.3 FW=1.13, which has been calibrated/adjusted using an LMG95 DMM for voltage (near 4.2V) and current (near 1.000A) before doing a 3-cycle discharge/charge (D-C) on an almost new pair of low self discharge Ikea Ladda 23076/703.038.76 (made in Japan) 2450 mAh AA LSD Ni-MH batteries using the SkyRC charger its battery type "Eneloop", model "Pro/XX AA" program at default 0.5C charge (1.25A) and 0.25C discharge rates (-0.62A).

The measured energy efficiency (according to the MC3000) is:
battery 1: -3.050 Wh versus +3.644 Wh = 83.7% 
battery 2: -3.038 Wh versus +3.707 Wh = 81.95%

How can this energy efficiency discrepancy be explained?
Isn't there a flaw in the energy efficiency graph in the starter of this thread?

Also: other source can only reach 92% charge/discharge energy efficiency for Ni-MH chemistry when using 50% of the SoC range.


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