A new wave of leaks suggests Apple could be preparing a major battery upgrade for the upcoming iPhone 18 Pro Max, potentially making it the longest-lasting iPhone ever released.
According to recently leaked certification information, Apple’s next flagship could feature a 5,567mAh battery in its eSIM-only version, while the model with a physical SIM tray may include a 5,391mAh battery.
If these figures prove accurate, the iPhone 18 Pro Max would carry the largest battery ever installed in an Apple smartphone.
Conflicting Leaks Create Uncertainty
While the latest numbers are impressive, they differ from earlier reports.
Previous industry leaks suggested a much smaller battery, estimating around 5,000mAh for the physical SIM model and between 5,100mAh and 5,200mAh for international versions.
The conflicting reports suggest Apple may still be testing multiple prototypes before finalizing the hardware.
eSIM Could Make Room for a Bigger Battery
One reason behind the reported battery increase is Apple’s continued transition toward eSIM-only devices in several markets.
Removing the traditional SIM card tray creates additional internal space, allowing engineers to install a larger battery without dramatically increasing the phone’s size.
A similar strategy is already expected for the iPhone 17 Pro Max, where the eSIM-only version is rumored to offer slightly more battery capacity than models with a physical SIM slot.
A20 Pro Chip Could Boost Battery Life
Battery size alone does not determine how long a phone lasts.
The iPhone 18 Pro Max is expected to debut Apple’s new A20 Pro processor, reportedly built using TSMC’s advanced 2-nanometer manufacturing process.
Industry expectations suggest the new chip could deliver:
- Around 15% faster CPU performance
- Up to 30% better power efficiency
- Improved battery management alongside iOS 27
- Enhanced performance from Apple’s next-generation cellular modem
Together, these upgrades could significantly extend battery life even under demanding workloads.
Bigger Battery May Mean a Heavier Phone
Several leaks also indicate that Apple may slightly increase the size and weight of the iPhone 18 Pro Max.
Recent reports suggest the device could become noticeably thicker than previous models and may weigh over 240 grams, making it one of Apple’s heaviest smartphones to date.
The extra weight would likely be the trade-off for a substantially larger battery.
Official Details Still Months Away
Despite growing excitement, none of the reported battery specifications have been confirmed by Apple.
The company is widely expected to unveil the iPhone 18 Pro lineup in September 2026, when official battery capacities, design changes, and performance improvements will finally be revealed.
Until then, these leaks should be viewed as early reports rather than confirmed specifications, though they paint an exciting picture for users hoping for a significant leap in iPhone battery life.
