Can you put the new iPad 3 battery in the iPad 2?
It looks like it's the same design and same connecter, so why not give it a shot?
In the words of Miro, our main man in charge of teardowns, "Probably not."
He points out that you could theoretically hook an iPad up to a car battery with enough tinkering and fiddling, but the feasibility of it working is very low. We believe roughly it's the same story for connecting batteries between different iPads. While you may be able to get it to work, they just weren't designed to interface with one another.
Won't fit. It's way thicker