I have had very good sucess with the Maha brand. MH-C204F that is a "Rapid
Charger & Conditioner for 2 or 4 AA/AAA NiCD/NiMH Batteries"

Further discription:
Microprocessor driven intelligent rapid charger.
Charge most batteries in about three hours.
Condition and rejuvenate batteries.

I have found that this product satifies all of these claims.

Steve
s/v Good Intentions