Apple is planning to feature an improved battery in its iPhone 7 Plus, according to reports, representing a 12.7% increase in battery size against those used in the iPhone 6s Plus. The next-generation iPhone is also expected to have improved storage options, offering a 256GB version on top of the 16GB, 64GB and 128GB versions available to iPhone 6 users.

The rumours, first spotted by MacRumors on the Chinese website MyDrivers, state that the screen sizes of the iPhone 7 and iPhone 7 Plus would mirror those of the iPhone 6 and iPhone 6s Plus, but would include improved configurations. The 3,100 mAh battery and 256GB storage option would be exclusive to the iPhone 7 Plus, the report claims.

MyDrivers had previously reported the so-called iPhone 6c would feature a 1,642 mAh battery and 2GB of RAM. Previous rumours surrounding the iPhone 7 have included a waterproof design and the inclusion of an all-in-one Lightning port to allow for a slimmer device.

Apple's product-release cycle dictates that the iPhone 7 would be announced and released in early September 2016. Typically, the latest generations of Apple's flagship smartphone feature a better camera and a faster processor than their predecessors.

An emphasis on thinness is expected to be made, with the possibility of removing the headphone port and the use of Bluetooth for connecting headphones and speakers. Other reports from China have suggested that Apple is already testing five different prototypes of the iPhone 7, with one reportedly featuring a dual camera. An AMOLED display is also reportedly featured on one of the prototypes.

Apple does not comment on rumours surrounding its forthcoming products.