AA NiMh - Shootout!!

[Mattaus]

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.

 

[socrates978]

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​

 

[bbb74]

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.

 

[pinetree89]

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.

 

[yota4by4]

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…

 

[snakyjake]

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]

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]

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.

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]

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]

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.

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

 

[mcnair55]

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]

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.

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.

 

[bbb74]

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.

 

[mcnair55]

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.

 

[bbb74]

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.

 

[tripplec]

Re: LSD Results

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

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.

 

[bbb74]

Re: LSD Results

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**).

 

[mcnair55]

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]

Re: LSD Results

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]

Re: LSD Results

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.