I haven't had any personal experience with them yet, but from what I've read
they are far lighter than NiMH.  As someone said the kokams are popular and
also now e-tec has some new li-polys that can deliver 7.5 A continuous.
Check out bishop power products: http://www.b-p-p.com

Lithiums are not as robust as NiMH though -- you have to make sure never to
discharge them below 3V/cell and their chargers are usually more expensive.  I
also read somewhere that if they rupture, they can release HF.  I'm not sure
if that's true or not (hopefully not), but it's something to think about if
you're looking at safety.

Mark

>Has anyone used the new Lithium Polymer batteries yet? They seem to be the
>only thing out there that can compete with NiMH for capacity per mass at
>high current drains (>1C). I found one company that claims to make them
>(Ultralife) but when I called one of their distributors, they said they
>would have to get back to me and have not done so yet. I don't see any info
>on price or leadtime. Any experience with these?

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