Battery performance may vary depending on the type of batteries used. Roughly, a set of alkaline cells cast last for 25 images, and Ni-MH cells can last for 200 images according to our test result. Konica Minolta recommends the usage of NiMH batteries only. Dirt on battery contacts is very likely to influence the battery performance. Before loading the batteries, strongly wipe both ends of batteries with a dry, clean cloth. Technically Ni-MH batteries are recharged less than the capactiy because of what is called "memory effect" when they are repeatedly recharged before completely consumed. I tis recommended to recharge the batteries only after the power is exhausted.