Does anyone make A-size NiMH cells, ideally high-capacity and low self-discharge?
The best I found is this, 2700 mAh 1.2V. The same capacity as Maha Powerex, so what's the point of getting A size.
http://www.batteryjunction.com/sy-mha2700b.html
Hey etc...
First, let me start by saying that I do not know the answer to your question. Fair warning that you can stop reading here.
Ok, if you are still there, here are a couple of reasons that the A 2700 mAh might be better than the Maha Powerex 2700 mAh:
1.) The A-size cell might have much better voltage retention at high currents, providing better power capability.
2.) The A-size cell might have better cycle life, capacity retention (i.e. lower self discharge) and faster charging capabilities.
I don't know if the above are true, but it is important to note that there is a lot more to performance than capacity.
I will make one more additional comment: in general, very common cell sizes (e.g. AA, AAA, C, D, 18650, 26650, etc...) are better designed and built than odd-ball sizes that are made in smaller numbers. The reason is simple: big companies with the expertise in battery manufacturing focus their efforts on making high volume cell sizes. And since big companies need to compete with other big companies, most of the product improvement efforts go into improving performance and quality of the high volume cell sizes. (And when I say "volume", I mean "manufacturing volume" and not the actual physical volume or size of the cell.)
So in answer to your question: "what's the point of getting A size?", the point might simply be that the A size fits in your device, and the reason that the capacity is the same as a AA Powerex cell is that whatever backwater, goofy company making the A size NiMH cell couldn't care less about improving performance because they have no competition for A size cells, and they know that 99.9% of people are going to buy their A size cell because IT FITS into the device.
This is, in large part, why I tend to stay away from anything that is not a AA, AAA, 18650 or 26650 for my flashlight applications.
Cheers,
BG
