At 09:42 AM 2/7/02 -0800, bblick wrote:
> > I am attempting to build a smart battery charger for
> > NiMH batteries (8-AA), with a F877. I am going to
> > use PWM to control a LM317, and sample the voltage
> > with the ADC to look for the delta V.
>
>No, that will not work. It may work a few times, but with 8 cells you will
>get a good peak only when the cells match perfectly. They won't do that
>very often. Also delta-V on NiMH is pretty mild. Works OK on NiCd.

You need to feed the batts a constant current, and look at both dV/dT and
dT/dT (temperature)

NIMH dosen't necessarily give you a peak or droop, so much as flatten to
zero delta for a while.

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