Hi all,

I'm having a bit of trouble figuring out some things about lithium
based rechargeable batteries. Since these are known to be rather
unforgiving, I figure I best ask before I make a dangerous mistake.

This revolves around a project I did about a year ago, based on a
14500 (AA size) lithium-ion cell and the MAX1811 charge controller.
This combination works great, and I'm quite happy with it. I'm now
looking at doing a smaller revision of the same style project, and I'm
not sure I'll be able to fit a 14500 into the new case. I have
considered going to a 10400 (AAA size). The capacity on these cells
isn't stellar though. I've also been looking at some flat
lithium-polymer cells. These look really attractive to me as they are
flat, which fits nicely in the bottom of my case, and have decent
capacity given their size. However, I'm finding all sorts of
information about charging, and it doesn't all match. Add to that
people tossing in the word prismatic, and the lithium-phosphate cells
(which I know are different and not acceptable for this current
application) and there's a lot of ways I can go wrong.

For testing purposes, could a charge controller like the MAX1811 work
for a battery like this one?

http://www.robotshop.com/ca/productinfo.aspx?pc=3DRB-Spa-109&lang=3Den-US

That would be ideal as I'd be able to evaluate run time using the
existing hardware before designing a new PCB. However, some sources
seem to indicate that LiPo cells need different treatment even though
they are a derivative of the Li-ion technology.

Also, I'm curious how the "prismatic" cells fit in to all of this.

Thanks!

Josh
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