The TENAA listings were highlighted by mobile leaker Steve Hemmerstoffer in a tweet, revealing that the iPhone 8 comes with a 1,821mAh battery, while the iPhone 8 Plus has a 2,675mAh battery.
If the TENAA listing is correct, the iPhone 8 line-up therefore features smaller batteries than last year's flagship Apple smartphones. In comparison, the iPhone 7 and iPhone 7 Plus feature 1,960mAh and 2,900mAh batteries, respectively.
Be that as it may, Apple claims its iPhone 8 devices offer "about the same" battery life as the iPhone 7 and iPhone 7 Plus when it comes to internet use, talk time, and audio and video playback over wireless.
It looks as if Apple has been able to eke out near identical battery life out of smaller batteries in the iPhone 8 devices thanks to the company's new high performance A11 Bionic processor, which Apple claims is more power efficient than previous chipsets.
The smaller batteries also boast support for wireless Qi charging and a new fast-charge capability, which means the iPhone 8 and iPhone 8 Plus can be charged to 50 percent battery life in 30 minutes using Apple's 29W, 61W, or 87W USB-C Power Adapters (sold separately and included with Apple's latest MacBook and MacBook Pro models).
In addition to the battery details, the TENAA listings also appear to confirm the iPhone 8 has 2GB of RAM and the iPhone 8 Plus packs 3GB of RAM, as previously reported.
We'll have to wait for the inevitable device teardowns for conclusive evidence about these specs. The new smartphones will be available to pre-order from September 15, with the devices launching on September 22. Prices start from $699 for the iPhone 8 and $799 for the iPhone 8 Plus.