The Canon LP-E6 Rechargeable Lithium-ion Battery Pack, has a capacity of 1800 mAh, so it is possible to shoot up to 850 shots at normal temperatures on a single battery charge. The battery is also more compact and lighter in weight than previous battery models. The LP-E6 Battery also communicates with the EOS 5D Mark II Digital Camera, so that you can always check the remaining capacity on the camera's power source info screen. In addition, a unique feature of the LP-E6 battery pack is that it has a microchip encoded with an 8-character serial number. So when the battery pack is installed in the camera, you can register it using a menu command. Then track the condition and power characteristics of up to 6 batteries in your camera to ensure you use your batteries evenly and identify batteries that are near the end of their useful lifespan.