According to leakster @OnLeaks, the new device might sport a 1960mAh battery, as compared to the 1715mAh battery found on the current iPhone 6S. This is especially good to hear considering that even the iPhone 6 had a larger battery than the iPhone 6S (1810mAh).
In tweet mentioned (Pretty reliable (not 100% but almost…) source told me #iPhone7 battery = 1960mAh (iPhone6s = 1715mAh))

iphone batteryRecently, an image of the 4.7-inch iPhone 7 was posted online. The image suggested that the new phone may feature redesigned antenna lines that go around the top and bottom of the device instead of the through the rear panel. Further, the camera lens also seems to larger than the current generation of iPhones.