Apple can’t seem to catch a break with leaks this cycle. We are still a couple of months away from the expected iPhone 18 launch window, but we already know a lot. Images, factory test details, possible colors, and camera upgrades have already surfaced. Now, battery capacity has also leaked.
According to a new leak on Weibo by 朵哥互联科技, the iPhone 18 Pro Max could ship with different battery capacities depending on the market. The version with a physical SIM slot is said to pack a 5,235mAh battery, while the eSIM-only version may go up to 5,425mAh.
Apple may finally cross a major battery line
Those numbers would be unusually large for an iPhone. More importantly, both versions would clear the Samsung Galaxy S26 Ultra, which uses a 5,000mAh battery.
Apple has never been the company chasing the biggest battery numbers on paper. Instead, iPhones have usually relied on tight hardware and software optimization to deliver strong endurance. A bigger cell in the iPhone 18 Pro Max, paired with Apple’s expected A20 Pro chip, could make battery life one of the phone’s most important upgrades.
The regional split also adds another layer to the story. Apple already sells eSIM-only iPhones in some markets, and removing the physical SIM tray can free up extra internal space. If this leak is accurate, that space may once again be used to fit a larger battery in eSIM-only models.
Samsung may not stay behind for long
The comparison with Samsung may not last forever. Rumors already suggest that Samsung is planning a battery upgrade for the Galaxy S27 Ultra, pushing it beyond the 5,000mAh mark that the current Galaxy S26 Ultra still sits on.
For now, though, both Apple and Samsung appear to be taking the safer route. Battery capacities may be increasing, but neither smartphone giant seems ready for a more radical shift to silicon-carbon cells, a technology Chinese flagship phones have used for years to fit much larger batteries without making devices noticeably bulkier.
