When you recharge a conventional battery before it is fully drained, the battery remembers it is using less than a full charge, resulting in a memory effect which is a loss of capacity.The Bower Digital Ultra Camera Battery Lithium-Ion battery is a high power battery and has no memory effect, therefore can fully charge it from any level. It can also be used with your existing camera charger, making it a perfect replacement for your digital or video camera.Replaces: Nikon EN-EL15 High Capacity 2500 mAh, 7.0V Fully Decoded