The Panasonic DMW-BCK7 Lithium-Ion Battery is designed to power select Lumix digital cameras, including the DMC-SZ5K. The DMW-BCK7 features a 680mAh capacity and 3.6V. Lithium-ion batteries are designed to withstand numerous charge cycles. They also resist the premature battery death known as "memory effect", which takes place when batteries are charged before they have been fully drained.