# AA NiMh - Shootout!!



## bbb74 (Jul 6, 2011)

In this thread: my 2011 shootout between 4 different models of rechargeable AA NiMH batteries. The contenders are:



4 x Vapex Instant 2500
4 x Eneloop (the newer 1500 cycle ones)
4 x Imedion 2400
4 x Powerex 2700


The batteries were donated for independent testing by Steve at www.electronicswarehouse.com.au (Vapex & Eneloop) and from Jeff at www.protog.com.au (Imedion and Powerex).


I have a wide range of tests scheduled to test various properties of these batteries, including capacity, variance, self discharge, high load, camera flash cycle times, high cycles, cold temps, and if the memory effect is a myth or not. I will be updating this thread with results as they come in. When I get bored I will do repeated long term self discharge tests (eg 6-12 months).


Notes:



All charging and capacity checks will be done on a Maha C9000 charger (Model 0J0CA).
The cells have been labelled VAP1-VAP4, ENE1-ENE4, IME1-IME4, and POW1-POW4.
In general, VAP1, ENE1, IME1, and POW1 will only be used in slot 1 of the charger, VAP2, ENE2, IME2, and POW2 will only be used in slot 2 of the charger and so on.
After charging, cells will be left in the C9000 for at least 2 hours after “DONE” appears for the 2 hour 100mA top up charge.


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## bbb74 (Jul 6, 2011)

*Initial Baseline Results*

Ok I now have the initial baseline tests in on all 4 sets of cells.


*Out of the packet remaining capacity*
Vapex: Average 1,745mAh; Stddev=**168**; Max-min=*340mAh*
Eneloop: Average 1,370mAh; Stddev=6; Max-min=13mAh
Imedion: Average 1,925 mAh; Stddev=12; Max-min=28mAh
Powerex: Average 281mAh; Stddev=6; Max-min=13mAh


Imedions have the highest capacity out of the packet, followed by vapex and eneloop. It should be noted one of the vapex had an odd result here – 3 cells were similar around the 1660mAh mark, and 1 cell had a capacity about 340mAh higher!?! Using them until flat out of the packet in a 4 cell device could have caused damage from the get-go.








http://www.flickr.com/photos/[email protected]/5942368957/


*Capacity (using breakin cycle)*
Vapex: Average 2,331mAh; Stddev=19.6; Max-min=46mAh
Eneloop: Average 1,994mAh; Stddev=7.8; Max-min=17mAh
Imedion: Average 2,278 mAh; Stddev=29.9; Max-min=58mAh
Powerex: Average 2,555mAh; Stddev=13.6; Max-min=29mAh


As percentages: 91% 78% 89% 100%
http://www.flickr.com/photos/[email protected]/5942368977/


*Tests with Canon 430exII full power pops*
There is a margin of error with these tests so I'm trying to phrase them in more general terms than the previous test so nothing is too misleading.


A freshly charged eneloop gives faster recycle times than any other cell. The other 3 were behind and roughly in the same ballpark, possibly the powerex were the slowest though and imedion best out of that group of 3.


After a ~500mAh discharge, eneloops were marginally faster than the other cells. The other 3 were pretty similar, but powerex were marginally the slowest again.


After a further ~500mAh discharge, Eneloop, Imedion and Vapex are pretty close (in that order), and the powerex were very slightly behind, maybe.


After a further ~500mAh discharge, Imedion, Powerex, and Vapex were pretty close (in that order) with the eneloops (now getting low in charge) a fair way behind.




*Voltage Curves*
See this graph:






initial voltage curve 



*Runtime test in Fenix LD20 torch*
Time to drop out of regulation in turbo mode, and relative performance:
Vapex: 117m (89.3%)
Eneloop: 99.5m (76%)
Imedion: 113.6m (86.7%)
Powerex: 131m (100%)
http://www.flickr.com/photos/[email protected]/5942926214/


Batteries and Torch refrigerated in large cup of cold water at 3 degrees Celsius, and run for 1h 15m. Capacity remaining in cells after this (discharged at 1000mA):
Vapex (average): 694mAh
Eneloop (average): 380mAh
Imedion (average): 719mAh
Powerex (average): 1004mAh




*Refresh&Analyse capacity test (+1300mA, -500mA)*
Vapex: Average 2,290mAh; Stddev=39.7; Max-min=97mAh
Eneloop: Average 1,931mAh; Stddev=15.6; Max-min=33mAh
Imedion: Average 2,240 mAh; Stddev=26.5; Max-min=54mAh
Powerex: Average 2,503mAh; Stddev=3.7; Max-min=8mAh
http://www.flickr.com/photos/[email protected]/5942926194/



*Any extra conclusions*


The powerex have a significant capacity advantage over the others, they also have the lowest variability in a refresh&analyse cycle, and the 2nd lowest in a breakin cycle. They appear to be slightly slower to recycle my flash, which was honestly a bit of a surprise result given they are popular with photographers.
Eneloops have the lowest capacity, but the lowest variability in a breakin cycle, and the 2nd lowest in a refresh&analyse cycle. Fresh eneloops cycle a flash the fastest, and maybe a touch faster when more than ~50% charged.
Imedions have a slightly lower capacity than vapex, but had more charge out of the packet
Vapex have the 2nd highest capacity and were less variable than the imedions in the first breakin test (3rd place vs 4th place), but switched to being the most variable in the final refresh&analyse test.
 All cells are now sitting out for a 1 month self discharge test. That will be followed by a ~1 week self discharge test. Then its either a longer (2 or 3 month) test? Or time to add more cycles??


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## bbb74 (Jul 6, 2011)

*LSD Results*

Results below are for a 31 Day self discharge test (cells were charged and then topped off for 2-3 hours at C/10 rate; discharge after 31 days was the normal 500mA).


*Average capacity: *
Vapex: 2110 mAh (stddev=40.7mAh; Max-min=98mAh)
Eneloop: 1806 mAh (stddev=12.6mAh; Max-min=28mAh)
Imedion: 2063 mAh (stddev=22.3mAh; Max-min=48mAh)
Powerex: 2291 mAh (stddev=13.2mAh; Max-min=31mAh)


*Relative capacities again the powerexs:*
Vapex: 92%
Eneloop: 79%
Imedion: 90%
Powerex: 100%


*Average mAh "lost" (vs original breakin capacity):*
Vapex: 222 mAh (9.5% lost)
Eneloop: 188 mAh (9.4% lost)
Imedion: 215 mAh (9.4% lost)
Powerex: 263 mAh (10.3% lost)


*My summary*


Powerex have the highest self discharge but its not bad, and starting out with the highest capacity, easily beat out all the other cells in capacity after 1 month.
Eneloops have the lowest self discharge, but started out with the lowest original capacity so still came last in capacity by a significant margin
Eneloops and Powerex had the lowest variation in capacity, followed by Imedion, then vapex
 *Notes*


Self discharge rates are much higher at the start of a period and slow down with time. I'm doing a 10 day self discharge at the moment. There are various physical mechanisms that cause self discharge, one of them only happens when the cell's voltage is above 1.23 according to Sanyo. So 2 or 3 month test results may show different performance.
These cells are still very much fresh – results may differ once cells have been used a bit more. That's the next step – going to put a bunch of cycles on the cells and then test self discharge and capacity again. Its going to take some time to get the number of cycles up – going to charge and flatten them repeatedly in a torch.


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## bbb74 (Jul 6, 2011)

*Other Results*

<reserved>


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## malow (Jul 6, 2011)

*Re: Other Results*

great work! as electronic enthusiast and photographer, your test are 2x useful!


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## bbb74 (Jul 16, 2011)

*Re: Other Results*

Updated baseline results now posted in second post above, for all 4 brands of cells.


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## samgab (Jul 16, 2011)

*Re: Other Results*

Very interesting tests here. Good work, I'll be interested to see the ongoing results...


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## ada_potato (Jul 18, 2011)

*Re: Other Results*

Are these all LSD batteries? (Eneloop=LSD) If not, aren't we comparing apples-to-oranges here?


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## MartinDWhite (Jul 18, 2011)

*Re: Other Results*

It would also be nice to see a test where you tested how much current each batter can put out at given loads. Current output at load is probably why the eneloops charged the flash faster.


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## bbb74 (Jul 18, 2011)

*Re: Other Results*



ada_potato said:


> Are these all LSD batteries? (Eneloop=LSD) If not, aren't we comparing apples-to-oranges here?


I kind of treat "LSD" as being somewhat of a marketing term. 3 of the types in the test are "LSD" but will probably have different self discharge rates. The powerex are not marketed as LSD but they are known to have a pretty low self discharge, which means they'll maintain a higher capacity than eneloops for quite a long time (many many months I believe). So they don't have a "LSD" label on them but they'll effectively beat eneloops in capacity terms for quite some time.



MartinDWhite said:


> It would also be nice to see a test where you tested how much current each batter can put out at given loads. Current output at load is probably why the eneloops charged the flash faster.


 That would be nice but I don't have have something that can do that! Eneloops and Imedions have already been tested like this in previous test on here if you are curious in the results. I'm trying to do real world tests (hence the flash), but yes I'd agree this is why the eneloops were the fastest on the flash test.


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## beerwax (Jul 19, 2011)

*Re: Initial Baseline Results*



bbb74 said:


> initial voltage curve


if you calculate the available energy from each battery as volts times milliamps (area under the curve) it would appear that an anyloop has similar capacity to the others listed here. a powerex might beat it but the extra bit of capacity is at poor voltage. 

cheers


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## bbb74 (Jul 19, 2011)

*Re: Initial Baseline Results*



beerwax said:


> if you calculate the available energy from each battery as volts times milliamps (area under the curve) it would appear that an anyloop has similar capacity to the others listed here. a powerex might beat it but the extra bit of capacity is at poor voltage.
> 
> cheers


 
Nah I very much doubt that! Otherwise why do all the other batteries have much longer runtimes in torches and flashes etc - pretty close to being proportional to their mAh capacities. Eneloops are simply one of the lowest capacity decent AA NiMhs around. 

Also note in the above graph, the minimum scale on the Y-axis is 1.05v. If I did the graph from 0v the difference between the cells would clearly be not that much. The graph effectively "zooms in" on the top part of what would otherwise be much taller columns.


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## Wrend (Jul 19, 2011)

*Re: Initial Baseline Results*

I would have preferred a little higher resolution than 5 to 6 points. The low V cutoff point seems a little high to me too. I think one of the standard discharge tests is at a 0.2C/h rate down to 1V (or 0.9V) per cell.

Still, I suppose discharging them all at 500mA does give you a "real world" test of sorts. I'm curious how they would compare at 1A or 2A, and how energy loss due to internal resistance would factor in.


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## bbb74 (Jul 19, 2011)

*Re: Initial Baseline Results*



Wrend said:


> I would have preferred a little higher resolution than 5 to 6 points. The low V cutoff point seems a little high to me too. I think one of the standard discharge tests is at a 0.2C/h rate down to 1V (or 0.9V) per cell.
> 
> Still, I suppose discharging them all at 500mA does give you a "real world" test of sorts. I'm curious how they would compare at 1A or 2A, and how energy loss due to internal resistance would factor in.



Sorry I could only be bothered checking every hour, they did go down to 0.9v. The voltage curve was just to get something to compare against once I've put a lot of cycles on the cells to see if there is a change, rather than do a full on voltage curve like I've seen silverfox and others do (with automated equipment). 

The runtime test I did in the LD20 would have been around the ~1.3A mark and as you can see, they all held up just fine and lasted a proportional amount to their actual mAh capacities. 1.3A is not hard for any half decent AA NiMh.


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## Wrend (Jul 19, 2011)

*Re: Initial Baseline Results*

Should have mentioned that I like the way you have them displayed together in the graph for easy comparison, though.



> Sorry I could only be bothered checking every hour...
> 
> ...rather than do a full on voltage curve like I've seen silverfox and others do (with automated equipment).


That's understandable.

One of the tests I did on one of my first sets of 8 Eneloops had me checking the voltage every 15 minutes for over 12 hours straight.  Can't say I'd recommend doing that (especially since I never did it again).

http://static.rcgroups.net/forums/attachments/2/7/0/8/7/5/a3143676-72-Eneloop%20T6EX%20Test%20Graph.jpg


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## InventPeace (Jul 19, 2011)

*Re: Initial Baseline Results*

Whats your conclusion for the "best buy" considering price, capacity, performance, life cycle years of use (LCY), etc. ?


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## beerwax (Jul 19, 2011)

*Re: Initial Baseline Results*



bbb74 said:


> Nah I very much doubt that! Otherwise why do all the other batteries have much longer runtimes in torches and flashes etc - pretty close to being proportional to their mAh capacities. Eneloops are simply one of the lowest capacity decent AA NiMhs around.
> 
> Also note in the above graph, the minimum scale on the Y-axis is 1.05v. If I did the graph from 0v the difference between the cells would clearly be not that much. The graph effectively "zooms in" on the top part of what would otherwise be much taller columns.


 
yeah i wondered about run times too - they do seem to reflect the milli amp hour capacity of the batteries used. i do observe tho that although i get clearly less runtime with an eneloop in a torch its generally brighter particularly as the runtime progresses. lower voltage in a flash would manifest itself as slower recharge time and you mightnt notice it. 
i just raised the issue because i cant recall seeing battery capacity expressed as watt hours , altho im sure it has been , and i thought it might be interesting to see. 

even if you extend the y axis to zero you still cant get away from the observation that a chunk of the extra capacity of these higher cap cells is really at low end of the voltage curve, and that the anyloop gives you all the cream that you get from a larger cap cell and that the cream is also sweeter. 

be interesting to see the graph from a XXloop

cheers


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## bbb74 (Jul 19, 2011)

*Re: Initial Baseline Results*



InventPeace said:


> Whats your conclusion for the "best buy" considering price, capacity, performance, life cycle years of use (LCY), etc. ?


Well I haven't tested life cycles yet. Where I live the vapex are the cheapest by a fair margin so if they held up with lots of cycles they'd probably be the "best buy". I bought eneloops for my TK41 recently because they were cheaper than the other brands (because they were coming in from overseas with the torch and didn't really cost anything postage wise), and because with 8 cells in the torch I wanted them to not have much variation to avoid reverse charging if I run it flat.

I think it comes down to want you're going to use them for.



beerwax said:


> yeah i wondered about run times too - they do seem to reflect the milli amp hour capacity of the batteries used. i do observe tho that although i get clearly less runtime with an eneloop in a torch its generally brighter particularly as the runtime progresses. lower voltage in a flash would manifest itself as slower recharge time and you mightnt notice it.


Any decent regulated light is unlikely to be brighter with an eneloop in it - that's the whole point of regulation (and its also why I used a well regulated light for my test ). An unregulated light might be a bit brighter with eneloops (I haven't tested this) but this means it will get flatter even faster.


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## beerwax (Jul 19, 2011)

*Re: Initial Baseline Results*



bbb74 said:


> Any decent regulated light is unlikely to be brighter with an eneloop in it - that's the whole point of regulation (and its also why I used a well regulated light for my test ). An unregulated light might be a bit brighter with eneloops (I haven't tested this) but this means it will get flatter even faster.


 
i understand my preon revo to be well regulated. i find it brighter on an eneloop. could be in my head i spose. its a aaa being drained in 50 minutes so its a big load on a tiny battery. i havent noticed it with my aa lights. 

cheers


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## menoceros (Jul 20, 2011)

*Re: Initial Baseline Results*

As to what has been said about the powerex being not completely LSD, thats an understatement. I've been using 2700 Powerex in my cameras fro several yeras and I find that the longest I can leave them is 4 months and then they're practcally dead. Comparing them to enloops or imedions is like comparing a Yugo to a Ferrari. This is why I changed to all LSD batteries in both my lights and my cameras .


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## bbb74 (Jul 20, 2011)

*Re: Initial Baseline Results*

How many cycles do your powerex cells have? Were they used in external flashes, or just in cameras?


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## Helmut.G (Jul 22, 2011)

*Re: Initial Baseline Results*

Thank you for doing this!
I'll be looking forward to the self-discharge testing results.


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## bbb74 (Aug 17, 2011)

I have edited the second post in this thread with the results of a 31 day self discharge test on the cells. Enjoy!


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## czAtlantis (Aug 18, 2011)

*Re: LSD Results*



bbb74 said:


> Results below are for a 31 Day self discharge test (cells were charged and then topped off for 2-3 hours at C/10 rate; discharge after 31 days was the normal 500mA).
> 
> Average mAh "lost" (vs original breakin capacity)



Hi, I'm newbie here but if I understand it right, I don't think you can compare capacity measured during break-in and with 500mA discharge. You should after break-in run discharge at 500mA, than charge and and after month again discharge at the same 500mA.


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## bbb74 (Aug 18, 2011)

*Re: LSD Results*



czAtlantis said:


> Hi, I'm newbie here but if I understand it right, I don't think you can compare capacity measured during break-in and with 500mA discharge. You should after break-in run discharge at 500mA, than charge and and after month again discharge at the same 500mA.


 
Its better than comparing against a refresh&analyse capacity.

The discharge during a breakin cycle is C/5 so for eneloops, 400mA, going up to 500mA for the powerex. So its close enough.


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## bbb74 (Sep 23, 2011)

*Re: LSD Results*

Just a quick update. Currently I'm cycling the test cells. They did something like 8 cycles each during the initial testing, and since then I've added 20 cycles each. To reduce the number of cycles yet cause a bit of "wear", many of the cycles are somewhat nasty. So far they've had:

* 2 over-discharges in a 2xAA torch with opportunity for reverse charging.
* 8 hours (3 cycles) in a stobe (about 250,000 on/off cycles each at about 1.2 amp when on)
* a few misc cycles in a torch, and a couple of "cycles" on c9000
* the rest are discharges for 60 or 66 minutes, with 2xAA cells in series into a 1.8 or 1.5 ohm 5 watt power resistor. All future cycles will be into the 1.5 ohm resistor, which is a current of about 1.6 amps which should be causing some "wear" on weak cells. The cells get mildly warm during this process, the resistor gets just a bit hot 

I'll probably add another 1 or 2 over-discharges and another 10 or 20 cycles on the 1.5ohm resistor, before I get sick of it all and repeat the capacity and self discharge tests, including a longer 3 month test. I can't be bothered doing more pointless cycles than that so it will have to do. I've got Imedions that have done almost 80 cycles bouncing around on my bike that are still at >=98% of original capacity and that just sounds like too much work...

On a side note, a few cycles ago my C9000 went a bit odd, with slot 1 consistently charging in about 70-80mA less per charge than the other slots, and it didn't matter which cell I put in slot 1 it would always be the lowest. Its going back to the shop for a check and possible replacement. I've bought a 2nd C9000 to cover me in the meantime, as even forgetting about this testing I go through a minimum of 6xAA's a day and can't afford to be missing the charger for a week or so. Anyway I did a refresh&analyse on 4 of my own cells to see if the 2 chargers gave different capacity results, and glad to say they were very close, within the normal variability you get if you do 2 refresh&analyses on the same cells in the same charger.


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## bbb74 (Oct 19, 2011)

*Re: LSD Results*

Ok capacity results are in after the batteries have had some cycles put on them!

*They've had the following "wear" cycles:*


8 cycles in original testing
3 "cycles" on the maha
2 deep discharges in an old torch until quite a while after there was no light coming out
~8 hours in strobe mode on a fenix ld20 (3 cycles)
3 cycles in old energeriser torch
31 cycles of 3/4 ish discharge connected 2xAA in series to 1.5ohm resistor
5 cycles of deep discharge connected 2xAA in series to 1.5ohm resistor for some good reverse charging action
IME2 and IME4 were accidentally dropped about 1.2m onto hardwood floor
A few others (which ones were noted) were accidentally dropped 30cm onto hardwood floor
All the ones that hadn't already been dropped at least 30cm, were dropped 30cm on purpose and then I was more careful after that 
All cells got a bit toasty sitting on top of my modem for a day (they were very warm but not hot)
= 55 cycles each

I have now done a Breakin on all of them and compared to the initial breakin they got, and (I have to admit I'm surprised) the results were pretty much what I expected!

*Average *change* in mAh from best to worst (negative numbers are a loss):*
Eneloop: +7mAh (+12, +6, +1, +8)
Imedion: +6mAh (+5, +14, +9, -6)
Vapex: -49mAh (-24, -49, -56, -67)
Powerex: -128mAh (-107, -91, -237, -78)

So eneloops and imedions are marginally better than when they were new (prob within the margin of error though). Vapex and powerex have lost capacity. The powerex have lost the most, which is what I expected based on my real world usage of them. My personal powerex are down to Imedion capacity, with the same type of usage.

*Now the average capacity of each set of cells is (from best to worst):*
Powerex: 2427 mAh (stddev=76.8, min=2312, max=2471)
Imedion: 2283 mAh (stddev=25.3, min=2256, max=2306)
Vapex: 2282 mAh (stddev=29.1, min=2246, max=2310)
Eneloops: 2000 mAh (stddev=8.7, min=1990, max=2011)

Powerex still have the highest capacity, Imedion and Vapex pretty much tied, eneloops still fair way behind. But eneloops have the least variation, and powerex the most. Imedion and vapex variation isn't too bad.

*Now the average capacity vs the Powerex as a %:*
Powerex: 100%
Imedion: 94%
Vapex: 94%
Eneloop: 82%

*SUMMARY of this post*

Eneloops have the lowest capacity but are the toughest and least variable
Imedions have more capacity than the eneloops and they they're not degrading so far either
Powerex have the most capacity but are falling much more rapidly than the others, and are the most variable. At the current rate soon they won't have the highest capacity any more.
Vapex have degraded somewhat, so they have now fallen (just) below the imedions in capacity

*Next...*
The cells are sitting around for a 10 day self discharge test, to be followed by 30 and 90 day test.

*The maha c9000 "problem"*
I bought a new, 2nd c9000, and it too is charging less into slot 1, although only about 30-40mAh compared to my original which is more like about 80-90mAh. I heard from another forum member who had the same issue with his, and his replacement was similar. When I finally send my old one back in 2 weeks I'll see what the replacement is like. Due to this, I stopped only putting cell #1 from each batch only in slot 1 when charging, and rotated them all evenly.

*The data...*
The data is here:
https://docs.google.com/spreadsheet/ccc?key=0AnF1KhnoruHSdDI5X2JVQ0ZXQzJaNlpqcklEU3dIOWc&hl=en_GB


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## bbb74 (Nov 20, 2011)

*Re: LSD Results*

Woohoo the 31 day self discharge results are in.


*Capacity after 31 days storage:*
Powerex: 2040 mAh (stddev=46.1; max-min=108 mAh)
Imedion: 1963 mAh (stddev=17.6; max-min=41 mAh)
Eneloop: 1791 mAh (stddev=6.2; max-min=14 mAh)
Vapex: 1790 mAh (stdev=24.6; max-min=56mAh)


Powerex still win after 31 days, has the highest variability though
Imedion a very strong second
Vapex and eneloops basically tied
Eneloops have amazingly low variability, very impressive
The Vapex had the lowest discharge voltage at the start of the test and 1 hour in compared to the others (I didn't check past this point)
The eneloops had the highest discharge voltage at the start of the test and 1 hour in
 *Average mAh "lost" over 31 days*
Vapex: 492 mAh (21.4% loss)
Powerex: 386 mAh (15.7% loss)
Imedion: 320 mAh (14.2% loss)
Eneloop: 209 mAh (10.4% loss)


Vapex lost more than the others in absolute and relative terms
Powerex aren't marketed as LSD but they didn't lose *that* much more than the Imedions in relative terms
Eneloops lost the least in absolute and relative terms, however they started out with the lowest capacity to start with
One of the 2 imedions that were dropped 3 feet to a hardwood floor (doh) lost ~30-40mAh more than the other 3
 *How the LSD test went THIS time vs when they were NEW:*
(mAh lost in 31 days)
Vapex: New=221 Now=492
Powerex: New=263 Now=386
Imedion: New=215 Now=320
Eneloops: New=188 Now=209


Self discharge of vapex has more than doubled
Powerex and imedion are up significantly
Eneloops are up marginally
Now that its summer, there has been warmer temps for the last 31 days so that will have increased the LSD rate vs the original test when the cells were new, this probably wasn't a large factor though when you look at the eneloop result.
 *Relative capacities against the powerex after 31 days:*
Powerex: 100%
Imedion: 96.2%
Eneloop: 87.8%
Vapex: 87.7%


*Next:*


10 day LSD test
90 day LSD test
The end??


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## Wrend (Nov 22, 2011)

*Re: LSD Results*



> The end??



Hey, as long as you keep going, I'll stop by and check it out. :thumbsup:

Thanks for your efforts.


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## greenlight (Nov 23, 2011)

*Re: LSD Results*

This was an interesting read as I use 4 Eneloop batteries in my camera (PENTAX Kx). I don't really understand the results and would probably try all the listed batteries if only to help me keep the cells grouped in units of four.


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## Helmut.G (Nov 24, 2011)

*Re: LSD Results*

It's nice to see the variability of the eneloops is so low.
Thanks for doing this testing!


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## dragonfruit (Nov 28, 2011)

*Re: LSD Results*



bbb74 said:


> On a side note, a few cycles ago my C9000 went a bit odd, with slot 1 consistently charging in about 70-80mA less per charge than the other slots, and it didn't matter which cell I put in slot 1 it would always be the lowest. Its going back to the shop for a check and possible replacement. I've bought a 2nd C9000 to cover me in the meantime, as even forgetting about this testing I go through a minimum of 6xAA's a day and can't afford to be missing the charger for a week or so. Anyway I did a refresh&analyse on 4 of my own cells to see if the 2 chargers gave different capacity results, and glad to say they were very close, within the normal variability you get if you do 2 refresh&analyses on the same cells in the same charger.



I asked MAHA about that quoting yours and the other fellow concerns. Their reply:

"Thank you for contacting Maha. Yes, this is perfectly normal as we
have a +/-5% tolerance on the electrical components and an additional +/- 1%
on the accuracy of the readout.

Regards,
Eric Cheng"

BTW, my AAA Vapextech Instant test results:
http://www.candlepowerforums.com/vb...exTech-AAA-Instant-950-mAh-LSD-batteries-test.


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## bbb74 (Nov 28, 2011)

*Re: LSD Results*

I don't think they really understood the problem. Its only slot 1 that is always out. The other slots are pretty consistent.


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## dragonfruit (Nov 29, 2011)

*Re: LSD Results*



bbb74 said:


> I don't think they really understood the problem. Its only slot 1 that is always out. The other slots are pretty consistent.




Well, tell them that by sending them a message like I did from their webpage.


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## socrates978 (Jan 18, 2012)

*Re: LSD Results*

Based on the 31 day discharge tests, it seems that the Vapextech are not true LSD...
They have lost over 20% of their initial charge - a similar amount to what might be expected for a non-LSD NiMh

What do others think?


----------



## dragonfruit (Jan 18, 2012)

*Re: LSD Results*



socrates978 said:


> Based on the 31 day discharge tests, it seems that the Vapextech are not true LSD...
> They have lost over 20% of their initial charge - a similar amount to what might be expected for a non-LSD NiMh
> 
> What do others think?



I think the same:
http://www.candlepowerforums.com/vb...exTech-AAA-Instant-950-mAh-LSD-batteries-test


----------



## socrates978 (Jan 19, 2012)

Thanks for the link dragonfruit

I'm doing some of my own tests.
I purchased Vapextech in December, went through a break in and several cycles.

Capacities as follows
2368
2396
2409
2320


The batteries were charged fully on 21st December.
I discharged the 1st battery at 500mah on 17th Jan until DONE displayed in MAHA C9000
Available capacity was 2039 mAh, compared to 2368 mAh on 21st December.
So at 28 days, the 1st battery has 86.1% of its original charge remaining.


My understanding is that Eneloops, consistently have 92-93% at 4 weeks. 
So, although the vapextech still has more capacity left than a fully charge Eneloop, it has lost more % wise.

14% capacity loss over 4 weeks still seems high and not that different from standard NiMh.
I'll report back with 6,8 and 12 week tests


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## socrates978 (Feb 1, 2012)

I have now got the 6 week discharge test for battery number 2. Discharged fully at 500mAh in MAHA
Initial capacity 2396
Capacity at 6 weeks 2057

So 85.9% remaining capacity at 6 weeks (42 days), & virtually no difference from the 4 week discharge I posted earlier. The self discharge rate seems to be levelling off.

So are these Vapextechs now behaving more like LSD batteries?
I'll report back with 8 week and 12 weeks discharge tests.​


----------



## samgab (Feb 1, 2012)

You mean discharged at 500mA...


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## socrates978 (Feb 2, 2012)

Yes, sorry meant 500mA

I was sceptical about the LSD properties of these Vapextech but maybe they have quite a high initial discharge rate and then level off. We shall see what the 8 week and 12 week discharge tests reveal


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## Mattaus (Feb 3, 2012)

Wow this is so weird...I have just decided to invest in some NiMh batteries and was looking around at alternative options to Eneloops (No idea why) and came across the Vapex brand. I was a bit unsure of them but reading this thread tells me that while they are not the best, they're still pretty good. On top of that I'm not really in the need for LSD batteries so that side of the coin does not affect me.

Vapex here I come :twothumbs

Awesome write up by the way. Great for people like me still learning about batteries.


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## socrates978 (Feb 16, 2012)

I have now got the 8 week discharge test for battery number 3. Discharged fully at 500mA in MAHA
Initial capacity 2409
Capacity at 8 weeks 2075

So at 8 weeks, the remaining capacity is 86.1%.
No difference in 4, 6 and 8 week remianing capacity. The AA version of Vapextech are behaving like LSD batteries.

At 8 weeks, they still have more capacity than a fully charged Eneloop, and here in the UK are cheaper - £10.50 for 8.
I'll see how they fare over the longer term compared to my Eneloops​


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## bbb74 (Mar 6, 2012)

Ok final self-discharge results in. Not quite the result I expected, will have to rerun the test on the Imedions to confirm, but I can't think of any reason at the moment why the result would be invalid.


Spreadsheet of all results: https://docs.google.com/spreadsheet/ccc?key=0AnF1KhnoruHSdDI5X2JVQ0ZXQzJaNlpqcklEU3dIOWc


Couple of graphs of self discharge results, including comparison of cells when new vs when used: https://docs.google.com/document/d/1YH7pmlaoCnsoNWxzX-Wd4oZGKHRytP-ftwdizSY4GFQ/edit


*90 day self discharge results

*
Average capacity remaining:
Powerex: 1878mAh (1931/1874/1830/1876)
Eneloop: 1726mAh (1727/1729/1729/1718)
Imedion: 1424mAh (1388/1291/1521/1496)
Vapex: 1047mAh (1068/923/1159/1038)


Capacity remaining as a percentage:
Eneloop: 86.3%
Powerex: 77.4%
Imedion: 62.4%
Vapex: 45.9%


Remaining capacity relative to powerex:
Powerex: 100%
Eneloop: 92%
Imedion: 76%
Vapex: 56%


Variability (stddev):
Powerex: 41.4
Eneloop: 5.3 !!!
Vapex: 97.4
Imedion: 105.8


The imedion result was odd because their self discharge seemed to accelerate from the 31 day test - they did well in the 31 day test and came second after the eneloops. My real world experience with imedions is that they hold a lot more charge than that at 90 days, however none of those real world cells have anywhere near as many cycles as these "used" test cells do. Also note there are different mechanisms of self discharge, and they take place at different rates depending on the charge level/voltage of the cell. I will put the imedions aside for another 90 days for a repeat.


*Capacity of the now used cells, vs when they were new*
Imedion: 99.6%
Eneloop: 99.5%
Vapex: 97%
Powerex: 88.6%


The poorer showing by the powerex here is borne out by my real world experience.


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## pinetree89 (Mar 8, 2012)

Fascinating. While you can find cells that fare better on individual tests, it appears that for the best complete package, Eneloop still rules the roost.

thanks for the write up.


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## yota4by4 (Apr 14, 2012)

To bbb74;
Thanks for your time.

I am deciding on which AA LSD to get..., I have been using PoweEx 2700’s, and Imedion 2100’s since ~2008. I started with 8 PowerEx 2700's, and the remaining 6 are not holding a charge very well anymore... I started with 16 Imedion 2100's, lost 4 (literally) and the rest seam to be doing pretty good.
I have tried to take care of them by using a MH-C9000 (also from ~2008)
 
 I have been looking around and I see:
 Imedion 2400 mAh: x4 ~13.00
 Eneloop XX 2400 mAh: x4 ~22.00
 Eneloop 2000 mAh: x4 ~11.00
 
Decisions…, decisions…


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## snakyjake (Apr 4, 2014)

Any test updates? This is the best review I've seen...one that I can easily understand and relevant to my use.

It would seem Maha Powerex 2700 is the best battery within 90 days. Eneloop if you need low resistance (camera flash). The Eneloop XX might be even better (not tested), but the price is high. There also might have been newer generations of the Eneloop since the last test (I recommend including the manufacturer's code).

Thanks. Jake.


----------



## tripplec (Apr 4, 2014)

*Re: LSD Results*

I have bought more eneloop cells and a pair of them the runtime was poor. The other new ones placed in the charger we not just topping up they started around the half way thresh hold base on the chargers LED status and did take quite a while to finish. This indicates that they're a lot lower than advertised out of the box. Not really useable as intended and more importantly as expected. The advertise them to be much higher when new. Also the amount lost in 31 days appears high for the design specifications. What happens after 3 months. It seems they'd need to be topped up be intended use or risk a premature failure especially if used on a trip in a camera.


----------



## ChrisGarrett (Apr 4, 2014)

*Re: LSD Results*



tripplec said:


> I have bought more eneloop cells and a pair of them the runtime was poor. The other new ones placed in the charger we not just topping up they started around the half way thresh hold base on the chargers LED status and did take quite a while to finish. This indicates that they're a lot lower than advertised out of the box. Not really useable as intended and more importantly as expected. The advertise them to be much higher when new. Also the amount lost in 31 days appears high for the design specifications. What happens after 3 months. It seems they'd need to be topped up be intended use or risk a premature failure especially if used on a trip in a camera.



Are you talking about real Eneloop Gen. 2, 3 or 4s?

I did a one year test with four batteries each of brand new Gen.2 Eneloops, GP ReCyKo and Imedion AA LSD batteries and after one full year, my Eneloops lost ~13%, the GP ReCyKos were at ~17% and the Imedions were at ~31%, as an average for those three quads.

http://www.candlepowerforums.com/vb...ut-Eneloops-GP-ReCyKos-and-Imedions-it-s-done!

Are you sure that you got real Eneloops, as there are fakes floating around out there, especially from Amazon vendors?

Chris


----------



## tripplec (Apr 4, 2014)

*Re: LSD Results*

They were 1500x charge cycles and should be the latest according to a version thread I read before buying them. The were bought in person at a reputable Photo store in New York City when I was there. Certainly not clones and have the same marking as the existing ones which were bought since this Dec. past.


----------



## ChrisGarrett (Apr 4, 2014)

*Re: LSD Results*



tripplec said:


> They were 1500x charge cycles and should be the latest according to a version thread I read before buying them. The were bought in person at a reputable Photo store in New York City when I was there. Certainly not clones and have the same marking as the existing ones which were bought since this Dec. past.



So they have the micro stamped date code near the wrapper's seam?

It's possible that you got a bad batch and your experience seems to be the exception, rather than the rule.

My Eneloops are all over 26 months and still going strong. 

I use a couple of good chargers, so maybe that's part of it?

Chris


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## mcnair55 (Apr 5, 2014)

*Re: LSD Results*

I applaud your efforts but in all honesty does it really matter or am i bothered,no i am not and i will buy Eneloop or similar purely on the best deal at the time.Tesco own label are good when on offer.I never count the amount of times i charge the batteries and "Instants" brand have been running for nearly nine years without problems.

Catch you later i am off to buy a new anorak.


----------



## Viking (Apr 5, 2014)

*Re: LSD Results*



tripplec said:


> I have bought more eneloop cells and a pair of them the runtime was poor. The other new ones placed in the charger we not just topping up they started around the half way thresh hold base on the chargers LED status and did take quite a while to finish. This indicates that they're a lot lower than advertised out of the box. Not really useable as intended and more importantly as expected. The advertise them to be much higher when new. Also the amount lost in 31 days appears high for the design specifications. What happens after 3 months. It seems they'd need to be topped up be intended use or risk a premature failure especially if used on a trip in a camera.



I know this doesn't change your bad experience. But I think it's safe to say what happened to you , happens very rarely.
I can't remember hearing about a similar episode involving eneloops. I think you just got some bad apples.
Try buy some others , perhaps from a different store.


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## bbb74 (Apr 5, 2014)

snakyjake said:


> Any test updates? This is the best review I've seen...one that I can easily understand and relevant to my use.
> 
> It would seem Maha Powerex 2700 is the best battery within 90 days. Eneloop if you need low resistance (camera flash). The Eneloop XX might be even better (not tested), but the price is high. There also might have been newer generations of the Eneloop since the last test (I recommend including the manufacturer's code).
> 
> Thanks. Jake.



I haven't done any further official testing but have continued to use the cells in question.

The powerex 2700's are at 82% after 19 extra cycles.
The VapexInstants are down to 2-80% of original capacity with 20 extra cycles.
The Eneloops are down to 84-99% of original capacity after *190 *extra cycles, all off them being bashed around on my bike, including two instances where the light flew off my bike onto a road at 50kmh and got driven over by a car.
The Imedions are at 77-98% after 20 extra cycles. My experience is that the imedions will go for 200-300 charge cycles total on my bike before their internal resistance builds up and they can't power a light in turbo.
The ansman maxE 2100's are at 97% after 105 extra cycles (gentle ones compared to the eneloops) so these are doing well.
The ansman 2800's are at 99% after 11 extra cycles and a lot of time in the fridge.


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## mcnair55 (Apr 6, 2014)

To make the test relevant surely you started on a level playing field as in all the sets were brand new and the date of manufacture were in a very strict tolerance of each other say all made Jan-Feb 2014 or so or June-July 2013 for example.


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## bbb74 (Apr 6, 2014)

mcnair55 said:


> To make the test relevant surely you started on a level playing field as in all the sets were brand new and the date of manufacture were in a very strict tolerance of each other say all made Jan-Feb 2014 or so or June-July 2013 for example.



To make your post relevant surely you read the first page of the thread where it says the cells were brand new.


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## tripplec (Apr 7, 2014)

*Re: LSD Results*



ChrisGarrett said:


> Are you talking about real Eneloop Gen. 2, 3 or 4s?
> 
> I did a one year test with four batteries each of brand new Gen.2 Eneloops, GP ReCyKo and Imedion AA LSD batteries and after one full year, my Eneloops lost ~13%, the GP ReCyKos were at ~17% and the Imedions were at ~31%, as an average for those three quads.
> 
> ...



Ok These latest cells I bought in New York City when I was there in a big Photo shop are. Eneloop 3UTGA 1900mAH and designated as 1800x charges with 5 year warranty on the card which I still have.


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## bbb74 (Apr 7, 2014)

*Re: LSD Results*



tripplec said:


> Ok These latest cells I bought in New York City when I was there in a big Photo shop are. Eneloop 3UTGA 1900mAH and designated as 1800x charges with 5 year warranty on the card which I still have.



Is there a date code imprinted on the cells? You may need to direct a strong light at them from the side.

What kind of charger were you using? What device is it that the 2 problem cells are having troubles in, and what kind of cells were you using in the device before you tried these eneloops? Compare with a batch from another source. It is also possible that if you were using alkalines before, the device's battery meter is not suitable to use with nimh batteries (which have a lower voltage compared to alkalines **when at very low load**).


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## mcnair55 (Apr 8, 2014)

bbb74 said:


> To make your post relevant surely you read the first page of the thread where it says the cells were brand new.



Being brand new means nothing as one set may have been made months before another and storage may have been in not a favourable place.


----------



## tripplec (Apr 8, 2014)

*Re: LSD Results*



bbb74 said:


> Is there a date code imprinted on the cells? You may need to direct a strong light at them from the side.
> 
> What kind of charger were you using? What device is it that the 2 problem cells are having troubles in, and what kind of cells were you using in the device before you tried these eneloops? Compare with a batch from another source. It is also possible that if you were using alkalines before, the device's battery meter is not suitable to use with nimh batteries (which have a lower voltage compared to alkalines **when at very low load**).



Eneloop *AA type 3UTGA* from the side of the battery!!!

I only use Eneloop cells.
I have an Nitecore I4 Charger (actually 2 now) and used it to top off the cells I removed from the package!! The two which died quickly were in another package I gave to my son who used them in a head lamp at work. He commented they did not last long. So putting new unused cells in the I4 charger they started on the 2nd LED level and stayed there quite a long time before moving to level 3.

This discussion has started to go sideways. Hence let me be clear!! I am NOT having problems with Eneloops nor with these brand new 1900mA ones (2 - 4 packs). I just stated that they're a lot lower in charge level than specified and document in the samples used here. Topping them off before use is highly recommended in m opinion.

Collectively we have over 2 dozen AA Eneloops now all less than 2 years old half less than 6 months now. All work well and are charged with he I4 charger.


----------



## Etsu (Apr 8, 2014)

*Re: LSD Results*



tripplec said:


> This discussion has started to go sideways. Hence let me be clear!! I am NOT having problems with Eneloops nor with these brand new 1900mA ones (2 - 4 packs). I just stated that they're a lot lower in charge level than specified and document in the samples used here. Topping them off before use is highly recommended in m opinion.



Sanyo doesn't fully charge them before shipping. IIRC, they charge them to about 75%. They do this because they can mass charge a whole bunch of them at once, using high current, without worry about overcharging or making them hot. By the time you get them, their charge may be down to 60 or 70%.

I've used them straight out of the box without issues. I've also charged them up before use. Both ways work fine, but charging them first is the way to go if you want them fully charged.


----------



## mcnair55 (Apr 8, 2014)

*Re: LSD Results*



Etsu said:


> Sanyo doesn't fully charge them before shipping. IIRC, they charge them to about 75%. They do this because they can mass charge a whole bunch of them at once, using high current, without worry about overcharging or making them hot. By the time you get them, their charge may be down to 60 or 70%.
> 
> I've used them straight out of the box without issues. I've also charged them up before use. Both ways work fine, but charging them first is the way to go if you want them fully charged.




+1 I have no issues with Eneloop either,i use them straight out of the pack for most items but will give them a charge if going in a camera.


----------



## bbb74 (Apr 8, 2014)

*Re: LSD Results*



tripplec said:


> Eneloop *AA type 3UTGA* from the side of the battery!!!


That's not the date code. The date code is imprinted on the clear coat wrapper, it is very hard to see but should be there.



> This discussion has started to go sideways. Hence let me be clear!! I am NOT having problems with Eneloops nor with these brand new 1900mA ones (2 - 4 packs). I just stated that they're a lot lower in charge level than specified and document in the samples used here. Topping them off before use is highly recommended in m opinion.


Ah ok. They don't come fully charged from the factory you realise? They're about 2/3rds to 3/4 charged.



mcnair55 said:


> Being brand new means nothing as one set may have been made months before another and storage may have been in not a favourable place.


A few months or even a year here or there isn't going to affect the results much. We all know eneloops are as a good a few years old as when they were new (presuming they haven't done lots of cycles). How do you suggest I should have improved the test - have an armed, climate controlled escort straight from the factory? All the cells came fresh from suppliers with high turnover, and as the suppliers were providing them free for comparative testing, it was in their best interest to provide their newest batteries. Some of the models tested had literally only just come into stock. I have never claimed the test was scientifically accurate. For example, it was not performed in a climate controlled environment. That alone would provide more variability then 1-12 months of age difference between batteries.


----------



## Power Me Up (Apr 8, 2014)

*Re: LSD Results*



tripplec said:


> Eneloop *AA type 3UTGA* from the side of the battery!!!



That's not the code that we're looking for. The code we need is embossed into the wrapper on the seam - As an example, the code on one of my 1st generation Eneloops is "06-0504"



> I just stated that they're a lot lower in charge level than specified and document in the samples used here. Topping them off before use is highly recommended in m opinion.



They do come precharged and ready to use as stated on the packaging, but they're not fully charged at the factory as others have stated. The 1st, 2nd and 3rd generation Eneloops were charged to 75% of their total capacity at the factory. The will of course self discharge a little over time and lose some of that capacity. In addition, their ability to hold their voltage under load will also drop as the cells get older and that can make a significant difference for voltage sensitive devices.

As an example, I discharged a pair of 1st gen Eneloops that had been sitting around for 8 years since manufacture and they held about 62% of their fully charged capacity and about 59% of their fully charged energy. For their out of packet discharge, they were only able to hold above 1.2V for the first 700 mAh or so. On the second discharge, they held 1.2V for about 1640 mAh.

From the sounds of it, you've probably got genuine Eneloops and the devices that you were using them in out of the packet were probably just a little too voltage sensitive to make full use of what capacity was remaining in them.


----------



## tripplec (Apr 9, 2014)

*Re: LSD Results*

It's *1 3 05LN* as it appears. Its stamped in an under the Sanyo Electric Company Ltd line.

As stated I would also recommend precharging them before using to get the expected runtime and no caught going dead.


----------



## ChrisGarrett (Apr 9, 2014)

*Re: LSD Results*



tripplec said:


> It's *1 3 05LN* as it appears. Its stamped in an under the Sanyo Electric Company Ltd line.
> 
> As stated I would also recommend precharging them before using to get the expected runtime and no caught going dead.



So May of 2013.

What charger are you using again?

Chris


----------



## funkychateau (Nov 6, 2014)

*Re: LSD Results*



bbb74 said:


> *The maha c9000 "problem"*
> I bought a new, 2nd c9000, and it too is charging less into slot 1, although only about 30-40mAh compared to my original which is more like about 80-90mAh. I heard from another forum member who had the same issue with his, and his replacement was similar. When I finally send my old one back in 2 weeks I'll see what the replacement is like. Due to this, I stopped only putting cell #1 from each batch only in slot 1 when charging, and rotated them all evenly.



I have noticed the same thing with my Maha charger, which I've owned for at least a couple of years. Slot 1 always shows the lowest capacity/charge mAH, with slot 4 the highest. This is independent of which batteries I put in the slots, so the charger variation is greater than the battery variation. This means that you can't compare batteries unless you charge and discharge every one in the same slot.


----------



## MidnightDistortions (Nov 6, 2014)

*Re: LSD Results*



Etsu said:


> Sanyo doesn't fully charge them before shipping. IIRC, they charge them to about 75%. They do this because they can mass charge a whole bunch of them at once, using high current, without worry about overcharging or making them hot. By the time you get them, their charge may be down to 60 or 70%.
> 
> I've used them straight out of the box without issues. I've also charged them up before use. Both ways work fine, but charging them first is the way to go if you want them fully charged.





tripplec said:


> It's *1 3 05LN* as it appears. Its stamped in an under the Sanyo Electric Company Ltd line.
> 
> As stated I would also recommend precharging them before using to get the expected runtime and no caught going dead.



I think the whole point of them being precharged is that you can use them out of the package. If they were over a year old i'd probably check to see if they need charging first but more than likely them being rechargeables i don't expect a full run time either, in fact i'd just rather use them instead of potentially overcharging them if they still had 75%+ charge left. I think there's some difference in capacities when they charge them as they charge them all using high current. I bought a 16 pack of Eneloops in September that were manufactured in April and May (they gave me 4 that were manufactured in April) but i charged a set that was pretty much charged, took 10 minutes in my BC-1000 charger, i didn't have to worry about another set of 4 that i was testing in my 2D Maglite using 2AA spacers. I got 8 hours out of that set, i probably would have gotten a little more if i topped those batteries off but i wanted to test how well these batteries worked out of the package. I left the other 8 batteries in the package considering they didn't really need to be topped off or refreshed though i plan on testing those in January or February as i might put all my refresh cycles in the beginning of January, though they probably don't need that either unless they were regularly used.

Anyway if you do want the expected runtime charging them up would work but if they were manufactured recently i'd just use them instead, it's pretty much the point of having them precharged. If they were dead or under 40% in the package then i would be a little worried on their lifespan, but either way it's up to those who get the batteries.


----------



## Power Me Up (Nov 6, 2014)

*Re: LSD Results*



funkychateau said:


> I have noticed the same thing with my Maha charger, which I've owned for at least a couple of years. Slot 1 always shows the lowest capacity/charge mAH, with slot 4 the highest. This is independent of which batteries I put in the slots, so the charger variation is greater than the battery variation. This means that you can't compare batteries unless you charge and discharge every one in the same slot.



I've speculated in the past that the cause of this is how the C9000 measures the cell voltages during a pause in charging:
http://www.candlepowerforums.com/vb...ther-3-slots&p=4472227&viewfull=1#post4472227

When it comes to testing capacities, it doesn't really matter too much as the 2 hour top off pretty much erases any difference in the main charge.


----------

