Apple continues to deal with leaks ahead of the iPhone 18 launch. Although the phone remains months away from release, details including images, factory test units, color options, and camera upgrades have already appeared. Battery capacity information has now surfaced as well.

A recent Weibo leak from 朵哥互联科技 suggests the iPhone 18 Pro Max could offer different battery sizes depending on the region. The model with a physical SIM tray is expected to include a 5,235mAh cell, while the eSIM-only variant may reach 5,425mAh.

Apple may finally cross a major battery line

These figures would represent unusually large capacities for an iPhone. Both versions would also surpass the Samsung Galaxy S26 Ultra, which features a 5,000mAh battery.

Apple has traditionally avoided competing on raw battery size, instead emphasizing hardware and software optimization for strong endurance. A larger cell in the iPhone 18 Pro Max, combined with the anticipated A20 Pro chip, could position battery life as one of the device’s key improvements.

The regional difference adds further context. Apple already offers eSIM-only iPhones in select markets, and removing the physical SIM tray frees internal space. If accurate, this leak indicates that space could be used for a larger battery in eSIM-only models.

Samsung may not stay behind for long

The edge over Samsung may prove temporary. Reports indicate Samsung plans a battery increase for the Galaxy S27 Ultra that would exceed the 5,000mAh capacity of the current Galaxy S26 Ultra.

For the time being, both companies appear to be taking a measured approach. Battery capacities are growing, yet neither seems prepared to adopt silicon-carbon cells, a solution already used in Chinese flagships to accommodate substantially larger batteries without increasing device thickness.