The Nikon EN-EL18 Rechargeable Li-ion Battery is designed for the Nikon D4 and D4S DSLRs and yields approximately 2600 shots per charge. Equipped with 10.8 V and 2000 mAh of power, this rechargeable Li-ion battery keeps your camera charged for a long time. This lithium-ion battery has a low self-discharge rate that helps it retain its charge for a long time.