The shape appears to be very similar to that of the batteries which are usually integrated into the iPhone.
The site notes that there is a detail that distinguishes them from the battery on the iPhone 5S and 5C.
A metallic section that can usually be found on current batteries now seems to be integrated along the side.
This may be seen as an indicator of a new design for the future iPhone.
Reuters reported earlier this month that the screens will be produced by LG Display, Sharp and Japan Display.