Much like in the Galaxy Nexus, we find a user serviceable battery in the Samsung Galaxy S III.

The 3.8 V, 2100 mAh battery incorporates the antenna for the Near Field Communications (NFC) module used in "S Beam".

For those who are curious, 2100 mAh is equivalent to 7560 Coulombs of charge. Unsurprisingly, this is the same amount of charge that a 3.8V, 7.98 Wh battery holds.