While the 5,000mAh figure is likely an estimate rather than a confirmed spec, it offers a clearer glimpse into what could be a substantial battery upgrade for Apple’s top-tier 2025 model.

For comparison, the iPhone 14 Pro Max came with a 4,323mAh battery, the iPhone 15 Pro Max increased to 4,422mAh, and the iPhone 16 Pro Max has a 4,676mAh unit. A move to 5,000mAh would represent nearly a 10% increase over the current generation.

Although a larger battery generally improves battery life, the final user experience will also depend on other factors, such as new hardware features, iOS 26’s software optimization, thermal management, processing efficiency, and display refresh rates.

Back in March 2025, another credible leak claimed that the iPhone 17 Pro Max would have a thicker chassis - 8.725mm versus the 8.25mm thickness of the iPhone 16 Pro Max. That slight increase may allow room for a bigger battery, potentially boosting capacity by around 400mAh.

The alignment of both leaks makes the information all the more plausible.

Apple to focus on battery optimization

Apple is expected to introduce a new charging system in iOS 26 aimed at extending battery lifespan through smarter power management.

While the optimization will apply to all devices, it's likely tailored with the upcoming iPhone 17 Air in mind, as that model is rumored to feature a smaller battery.

Meanwhile, Apple’s foldable iPhone - known as iPhone Fold - is also facing battery challenges due to the need for a thinner frame. Apple is reportedly redesigning the foldable screen to improve battery performance.

In addition, the iPhone 17 Air (also rumored to be named iPhone 17 Slim) is expected to use next-gen silicon-anode battery technology developed by Japan’s TDK. This innovation is said to deliver up to 15% more energy than current designs.

However, the technology has just become viable for mass production and will likely be exclusive to the iPhone 17 Air this year. If successful, it could debut on the iPhone 18 Pro Max in 2026.

The Pro Max model traditionally offers better battery life than the smaller Pro version - but this year, that gap may widen even further.

Current battery performance for the iPhone 16 Pro Max, as published by Apple, includes up to 33 hours of video playback, 29 hours of streaming, and 105 hours of audio playback. The iPhone 17 Pro Max is expected to surpass those benchmarks.

The iPhone 17 lineup - comprising iPhone 17, iPhone 17 Pro, iPhone 17 Pro Max, and the ultra-thin iPhone 17 Air - is set to launch this September as per Apple’s annual schedule. While the Pro models remain the center of attention, this year the arrival of the ultra-thin iPhone 17 Air is adding a major twist.

Hai Phong (AppleInsider, 9to5mac)