Ron Hardin crawled to the nearest keyboard
and summoned the courage to write:

I need to toss out NiMH batteries that won't hold enough charge (the
Pogo RipFlash destroys itself if the battery dies while recording).

Is there a quick way to test battery capacity?

Inelegant but works: charge the battery, insert it in a
single-battery holder, put a resistor across the leads, then measure
the time and voltage as it runs down.

Ohm's law: E = IR rearranges to I = E/R. For a single NiMH under
load, E is 1.2 volts or thereabouts. You might specify I so as to
drain the battery in an hour. I think the RipFlash uses AAA
batteries, so if the battery capacity is (just guessing) 900 mAh then
to flatten the battery in about 1 hour you'd have a drain of 0.9 amps
(=0.9 Ah / 1 h). Then R = 1.2/0.9 or a little over 1 ohm.

Note the power is I^2 R or about (0.9*0.9)(1) = 0.8 watts, so you'll
need a fairly high-wattage resistor, or achieve the desired R by
putting several resistors in parallel so they share the load.

I would guess that a weak battery might show a lower-than-usual
voltage under heavy load but don't know for certain. This would spare
you having to completely drain the battery.

HTH.



--
"The Great Satan put electricity in my toothpaste."