Well lookie lookie...what have we here? The rear panel is easily removed, revealing both SIM and microSD card slots, as well as what seems to be a replaceable battery!

As predicted (not that we're psychic or anything) the battery is easily removable, thus easily replaceable. Thanks, Samsung!

You may be asking yourself what powers this device?

The 3.7V Li-Ion battery inside the Galaxy S 4G lists a capacity of 6.11 Watt-hours, or 1650 mAh.