motorola
Motorola DROID RAZR MAXX battery fits into the Droid RAZR
However it should be noted that all of this is done at your own risk, and there are chances of something going wrong. For example it seems that by installing this new battery, it might ruin the aesthetics of your phone as it leaves a slight gap between the SIM card door and the battery cover. But if you think that’s a small price to pay for double the battery life, pop on over to the XDA forums for more info.