Apple’s slimmest device? New leak shows 2.49mm battery for iPhone 17 Air

Fresh leaks about the iPhone 17 Air have surfaced, providing new insight into what may be Apple’s thinnest iPhone to date. The latest images, posted on Korean blog Naver and shared by leaker Majin Bu on X, show a prototype battery said to belong to the iPhone 17 Air, revealing its extreme thinness and design upgrades.

The battery, pictured alongside a precision calliper, measures just 2.49mm in thickness, less than half the thickness of the battery reportedly intended for the iPhone 17 Pro. It also features an L-shaped layout and a steel casing, a material choice previously used in the iPhone 16 Pro to improve heat dissipation and structural durability.

If confirmed, this leak reinforces widespread speculation that the iPhone 17 Air could be slimmer than any iPhone yet, including the iPhone 6 (6.9mm). Estimates suggest the new model may be between 5.5mm and 5.8mm thick, with some reports hinting at a sub-6mm profile.

Features

The prototype battery is said to have an estimated capacity of 2,900 mAh. Though relatively modest, the design aims for efficiency, leveraging Apple’s optimisation of both hardware and software to extend battery life despite its compact size.

The steel case offers several benefits, including:

– Enhanced heat dissipation

– Improved structural integrity

– Advanced internal integration

According to reports, the battery also includes welded edges and utilises new adhesives to facilitate easier replacement, an improvement in line with Apple’s push toward repair-friendly designs.

Potential for faster charging

While there is no official confirmation on charging speeds, the presence of a steel shell hints at an upgraded thermal management system, potentially enabling faster charging, similar to what was introduced with the iPhone 16 Pro.

The battery shown is reportedly a prototype under development, intended for the iPhone 17 Air, which is expected to launch in September 2025. Apple has not officially commented on the leak or shared any specifications for the upcoming iPhone 17 lineup.

Images accompanying the leak also show the battery mounted with precision callipers, confirming its 2.49mm thickness, and a separate image of the heat-dissipation adhesive, an integral part of the battery’s mounting and thermal system.