The image corroborates a previous report which said the 4.7-inch iPhone 6 would have a 1800 to 1900 mAh battery. This is better than the 1570 mAh battery of the iPhone 5s; however, the larger screen may negate the increased capacity.
The 5.5-inch iPhone 6 is said to feature a 2500 mAh battery. You can follow iClarified on Twitter, Facebook, Google+, or RSS for updates.
Take a look at the image below...