I just spent $130 and got a universal nicd/nimh/pb/lion charger.
It charges up to 24 cells (28v) and includes diagnostics and cycling,
but runs off a car battery. Look for R/C hobby chargers ;-)
I got the Triton charger by Electrifly, from helihobby.com. I can
program the charge rate, but it can charge my 18v drill in 20 minutes,
and it tells me how many mAH it put into the battery.