V G wrote:
> I figured a simple way to profile them was to measure under-load
> voltages while draining the cells with some resistors at around 500
> mA. But this would mean current drain would decrease as the battery
> voltage decreases.

That's not a big deal.  Make really sure you have a circuit that cuts off
when the battery gets low enough though, else you will damage it.  You coul=
d
simply measure the time from fully charged until the circuit cuts out to
compare capacity of different cells.  You may not know the exact capacity,
but the comparison will still be valid.

NiMH cells don't drop that much in voltage over most of their life, so
you'll actually have a pretty good absolute idea of capacity too.

If you really want to measure capacity, you can measure the voltage over
time.  Since you know the resistance, you know the current, then integrate
that.  Even once per minute would be good enough since you're talking about
a discharge time of a few hours.


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