Update August 4: Majin Bu posted a report on Monday about the iPhone 17 Air battery, which is essentially the same report Bu posted last Friday. That Friday report, however, was retracted by Bu, who erroneously stated that it was the iPhone 17 Air battery, and meant it to be the iPhone 17 Pro battery. This article has reinstated the sections that were struck because of Bu’s retractions.
Update August 2: Majin Bu has revised the initial report that this is an iPhone 17 Air battery. Bu now states that it is an iPhone 17 Pro battery. This article has been revised to reflect Bu’s change. Original statements have been struck but are left in the article for historical context. The original headline for this article was, “The iPhone 17 Air’s battery will reportedly be very small and extremely sturdy.”
Leaker Majin Bu has details on what is possibly the battery of the upcoming iPhone 17 Air, the new ultra-thin iPhone that Apple is rumored to unveil this fall. The report follows one last Friday by Bu about the iPhone 17 Pro battery (which Bu initially and erroneously reported as the iPhone 17 Air battery).
Bu states that the battery has a capacity of 2900 mAh, which, for reference, is smaller than both the 3582 mAh of the iPhone 16 Pro and the 3561 mAh of the iPhone 16. The 17 Air’s smaller capacity isn’t surprising, considering that the phone is rumored to be noticeably thinner. And while the 17 Air’s capacity is similar to that of the iPhone XR (2942 mAh) from 2018, drawing any conclusions based on the XR’s battery life (which was 11.24 watt-hours) isn’t relevant, since battery technology, internal components, and iOS energy efficiency have changed in the past seven years.
In the 17 Air report, Bu compares the battery side-by-side with the supposed 17 Pro battery, and it appears to be much thinner. Bu does not state the capacity of the 17 Pro battery.
Bu also states that the battery will use a steel case like the one used with the iPhone 16 Pro. It seems likely that the steel case will be used throughout the iPhone 17 lineup to provide improved heat dissipation, higher structural resistance, optimized integration, as well as “higher charging powers,” Bu writes. In June, a report stated that the iPhone 17 could support the Qi 2.2 standard that allows for up to 50 watts of wireless charging.
Apple’s Awe Dropping event is set for September 9, 2025. Want to know what to expect? We’re anticipating new hardware releases including the iPhone 17 (running iOS 26), Apple Watch Series 11, Ultra 3 and SE 3rd-gen (running watchOS 26), and potentially new AirPods. Find out how, when, and where to watch the Apple September Event, and keep tuned to our Event Guide for all the latest coverage. If you just can’t wait, here’s our satirical take on the Apple September Event keynote script – and don’t miss the Macworld Podcast iPhone event preview.
Author: Roman Loyola, Senior Editor, Macworld
Roman is a Macworld Senior Editor with over 30 years of experience covering the tech industry, focusing on the Mac and other products in the Apple ecosystem. He is also the host of the Macworld Podcast. His career started at MacUser, where he received Apple certification as a repair technician (when Apple did that kind of thing). He's also worked for MacAddict, MacLife, and TechTV.