If you are looking for a flashlight with long lasting battery, you may consider a new product called Seven Year Flashlight from Hammacher. As its name, this flashlight battery can keep its power up to seven years in single charge. It uses a Nickel Metal Hydride battery that designed specifically for this flashlight to minimize power loss.
The Seven Year Flashlight produces 200 Lumens of bright light which can be used up to six hours of operating time on full charge condition. The flashlight comes with three AAA backup batteries that can provide up to 10 hours. On the handlebar of the flashlight it has a solar panel which functions as a natural charger (can be charged under sunlight or artificial light). This long lasting Flashlight also can be charged via included AC or DC adapters.
If you need one you can buy it from Hammacher for $59.95 each unit. Seven Year Flashlight is backed by Hammacher Schlemmer Lifetime Guarantee at no additional charge.