I've been using http://www.batteryjunction.com/rc390reliba.html with the charger that came with them. Originally I ordered different batteries and the Tenergy charger but Battery Junction alerted me that the battery and charger were incompatible. Great service on their part!

I know nothin' about batteries. Can't educate you. I feel fortunate to have found a battery dealer who is looking out for my interests and safety.