Everything we know about the iPhone 8's battery life (AAPL)

The upcoming iPhone 8 is arguably Apple's most hotly anticipated device for several years — and one of the biggest unknowns about the device is how long the battery life will last.

While we won't know for sure until Apple releases the flagship device, the rumour mill is already in overdrive, with people keen to know whether the iPhone 8 battery will outlive the battery in the iPhone 7 and the new Samsung Galaxy S8.

Rumours suggest that Apple will put a 2,700 mAH battery in the iPhone 8, which would almost put it on a par with the 2,900 mAH battery in the 5.5-inch iPhone 7 Plus. The question analysts are asking is how will Apple put such a large battery into a smaller phone.

Flagship phones and how long their batteries last (via

Several reports have suggested that Apple plans to shrink many of the components inside the chassis of iPhone 8 to make room for a larger battery.

KGI Securities analyst Ming-Chi Kuo — an analyst renowned for his Apple predictions — believes Apple has conceived a clever plan to get a bigger battery into its upcoming flagship handset.

The plan involves using a "stacked" logic board that has a smaller overall footprint inside the iPhone. Shrinking the logic board, which holds and allows communication between the iPhone's other components, will also reportedly improve energy efficiencies in the iPhone 8. As a result, Kuo expects that the iPhone 8 battery could be even better than the battery life on the iPhone 7 Plus.

Elsewhere, Cowen and Company analyst Timothy Arcuri, who has a mixed track record when it comes to iPhone rumours, predicts that the largest of Apple's new iPhones could come with two batteries, resulting in an extended battery life.

Kuo also seems to believe that Apple will adopt a "two-cell design" approach, with Apple Insider reporting that he thinks the two batteries will form an L-shape within the iPhone 8. Kuo reportedly thinks that the new battery design will enable quicker charging speeds.

In addition to wired charging via a Lightning cable, it's possible that future iPhone 8 owners will also be able to charge the battery on their new device wirelessly, with leaked photos suggesting that the iPhone 8 will support contact-based wireless charging. This would allow iPhone 8 owners to charge their phone simply by placing it onto a compatible charging pad.

Other iPhone 8 rumours can be read here.