Hi all.....has anyone homebrewed a lithium ion bat charger? I have a Canon
G5 that uses a 7.2 vdc bat pack and am thinking of homebrewing something
with a LM317 or other chip but need to know what will do the job without
ruining the lithium ion bat pack.

Lithium cells are quite tricky to charge properly. They require
tightly-regulated charging voltages and charging-current rates, and
special treatment when in deep-discharge states or when nearing full
charge. It's quite easy to damage them by using incorrect charging
protocols, and this can be quite dangerous - their stored-energy
content is high, and their active material is distinctly flammable.

I would not try to homebrew a charger using an LM317. It _might_ be
possible to homebrew a charger using one of the special-purpose
lithium-battery-charger chips from Maxim, LT, National Semi, etc., but
I'd be rather reluctant to try unless I _really_ needed one of this
sort.

--
Dave Platt AE6EO
Hosting the Jade Warrior home page: http://www.radagast.org/jade-warrior
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