Although most iPhone users will never see it, it appears that the battery in the iPhone 16 Pro will be distinctly different from the one in the current model.

This is according to leaker Kosutami, who shared a photo of an "early stage" prototype battery that is believed to be included in the iPhone 16 Pro. While maintaining the L-shaped shape traditionally seen on the device, it comes with a metal shell instead of foil as in previous years.

Assuming that the prototype is the real thing, the goal seems to be to improve heat, as metal helps disperse heat rather than concentrate it; given early reports of the iPhone 15 Pro unit getting very hot, that would certainly be welcome (even even if the complaints seem to have largely disappeared after the software update).

Intuitively, one might think that moving to metal would make the phone heavier, but not to worry; as MacRumors points out, Apple has already switched up the wearable's battery with the 41mm Apple Watch 7.

The photo above, by iFixIt, shows the difference between the foil version of the 45mm Watch (right) and the metal version of the 41mm version (left).The 41mm aluminum Apple Watch 7, despite having a slightly larger screen, weighs just 1.5 grams less than the 40mm previous Despite having a slightly larger screen, it is only 1.5 grams heavier than the previous 40mm model.

Costami, who previously revealed a prototype of the screen-equipped HomePod, also revealed the battery specs for the iPhone 16 Pro, which has a slightly larger capacity than this year's version. It will reportedly have 3,355 mAh, up about 2.5% from the current 3,274 mAh.

While this may not seem like a big deal, it could still prove significant in conjunction with a less power-hungry screen and a more efficient upcoming A18 Pro chipset.

The iPhone 16 rumors are still early days and the device is not expected until September 2024. Most of the early buzz is about the premium models, with both the Pro and Pro Max handsets reportedly having larger displays and more powerful camera magnification thanks to a new kind of lens. There is also talk that Apple will introduce a separate capacitive button on all iPhone 16 devices, specifically for photography.