If you use digital camera infrequesntly than the best batteries are disposable AA Alkaline Batteries. But for frequent users, best batteries are rechargeable, which can be used upto 1000cycles. Such batteries can work in multiple environments.
Useful Tips
a] If you do lot of shooting use rechargeable batteries
b] Keep Spare battery and Charger for Regulare Users
Camelion Chargers are designed to meet various situations and need. Camelion 905B is a Ultra Fast Charger with Auto Cut. It Charges Batteries in Approx. 6Hours.