Logan Shaw wrote:

Scott Dorsey wrote:

I just don't trust any rechargeables enough to use them for critical
work.


Interesting. I'm sort of the opposite.
...
with today's improved rechargeable technology,
if I give someone a wireless mic and they use it for only 30
minutes, I can drop that battery in the charger and it will
quickly charge back up to 100%. In the old days, we had NiCd
batteries and they had "memory", so you had to discharge them all
the way or risk shortening their life. You don't have to do that
anymore with NiMH batteries. Also, in the old days, chargers were
dumb and based on timers, so if you put a partially-discharged
battery in there, it would charge it like it was fully drained
and reduce its life. But modern chargers sense voltage and
temperature changes and and can just stop when the battery is
actually charged. So there is no problem putting a battery in
when it has only discharged by, say, 25%.

I have very high confidence in AA NiMH cells but my experience with the 9V (and other multi-cell packs) is not so great.

If more of the wireless TX manufacturers would put modern switchmode supplies in their products, they would run nicely off AA NiMH cells.

9.6V x 200 mAH = 1.92 Watt-hours
1.2V x 2200 mAH = 2.64 Watt-hours

See what I mean? The higer voltage cells suffer in terms of volumetric efficiency...