Battery performance might vary, depending on the type of batteries used. Konica Minolta recommends the use of AA 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 capacity, because of what is called "memory effect". It occurs when they are recharged repeatedly, before completely consumed. It is recommended to recharge the batteries only after the power is exhausted.