iPhone 17 Air leak shows off impossibly thin battery — and it's bigger than we thought

We are so close to the launch of Apple's next iPhone generation. The iPhone 17 series is expected to be officially announced next month, and consistent rumors have suggested that there will be an iPhone 17 Air accompanying the usual suspects.

A new rumor from reliable leaker Mijan Bu reveals the iPhone 17 Air's battery capacity, which is reportedly 2,900mAh, slightly larger than initially expected. The leak also says the battery is housed in a steel case.

Previously, we had heard that Apple's extra-slim phone would have a 2,800mAh battery. Sure, it's only 100mAh difference, but when you're talking about a battery that small (the iPhone 16 uses a 3,561mAh battery, for perspective) any extra juice is a good thing.

As scary as a battery that small is, reports indicate that it'll still offer a full day of battery life thanks to improvements in battery life technology and some performance tweaks in iOS 26. Obviously, we'll need to test this for ourselves to see if a battery under 3,000mAh can really meet the demands of iPhone users, but I'm hopeful.

The battery is expected to be small, as previous reports have indicated that the phone will be just 5.5mm thick. The iPhone 16 is 7.8mm, so there's a noticeable difference in depth between the current phone and the rumored Air. If Apple manages to get to that rumored thickness, that would just beat the Samsung Galaxy S25 Edge, which measures 5.8mm.

Apple may not be the first to release a thin phone, but it might have the thinnest, which seems to be the way Apple operates.

The iPhone 17 Air is rumored to replace the iPhone 16 Plus in Apple's lineup, meaning the company would still release four devices — iPhone 17, iPhone 17 Air, iPhone 17 Pro and iPhone 17 Pro Max.

The current prevailing rumor has said that Apple will hold its iPhone 17 event between September 8 and 10, so we won't need to wait too long to learn all about the thin iPhone on the horizon.

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