They both output 39.4V (the email said this is normal with no load)
    and they both output 100ma.  Does anyone have any suggestions?  Does
    anyone know of a source for a 24V, NiMH smart charger?

Define "smart"?  It sounds like the charger you have has an actual constant
current source in there someplace, which is a bit more than most chargers
(which typicall JUST have a resistor.)

I own a couple NiMH chargers, and my favorite so far is the one from Sears
(believe it or not.)  It apparently has a timer and drops the charging
current to "trickle" after the timer expires.  Of course, that's a single
cell (actually two cells at a time) charger, so it won't do anyway :-(

To be considered a SMART charger, I would think it should automatically
detect end-of-charge (ie by detecting dT/dt or dV/dt, or something) and
drop to trickle (or turn off.)  I haven't seen very many like that, though.
Perhaps having loose cells interferes with proper temperature sensing?
I think they're all either lazy or afraid that no one will PAY for a smart
charger (could be right - the $200 price tags on LiIon Packs are absurd!)

100mA isn't much of a charger for a 4000mAh, is it?  Shouldn't you have at
least 400mA for a C/10 12-hour charge, and significantly higher than that
for faster charging?  I don't know if 100mA even qualifies as "trickle."

BillW

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