>
>
> I'd be careful with this - I have a feeling that a worn-out cell doesn't
> go into negative dV, and you end ep
> cooking it.  I can't say for sure, but I've had very sophisticated
> chargers end up frying cells that I
> believed to be a bit dodgy, but wanted to see if they'd charge...


I would terminate high rate (or not start high rate) on one of several
conditions: (1C charge assumed)
T < 0C
T>40C
dT > 2 degreesC/min UNLESS the cells are below room temperature.
dV = 0 for 30S
dV negative, with a 10 min lockout
Pack voltage exceeding 1.5V/Cell

I measure at the end of short pauses that happen once a second.




And I think you need to be even more careful if you're charging a battery
> rather than individual cells - one
> cell's +dV may mask another's -dV !


Indeed they do.  Very good idea not to make up packs from cells with
dis-similar histories
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