I'm using Canon LP-E8 Battery Pack, recommends you buy from a reputable source like Amazon to assure you receive a genuine item. My 2 Pack of batteries have outperformed my factory battery by leaps and bounds. I received a pair of 2000mAh batteries like many other people have and they simple shoot all day. With a fully charged battery, you can simply take thousands of pictures. I have taken thousands of pictures with these batteries and they are flawless. Worth every single penny!