Nearly 12% more battery. That’s not a rounding error, that’s a real jump. A leaked photo circulating online suggests the iPhone 18 Pro Max could carry a 5,391 mAh battery, up from the 4,823 mAh cell inside the current iPhone 17 Pro Max. If accurate, this would be one of the more meaningful spec bumps Apple has made to the Pro Max line in recent memory.
According to MacRumors, the image shows a battery pack labeled for a Chinese model of the iPhone 18 Pro Max, complete with a SIM card tray. The photo first appeared on the Korean platform Naver but reportedly originated from Chinese social media platform Weibo. Take it with the usual grain of salt. Supply chain leaks from Weibo have a mixed track record, and a single photo of a battery label is far from confirmed. But the specificity of the numbers, 5,391 mAh is oddly precise for a fabrication, makes it worth paying attention to.
So why does this matter? Battery life is consistently one of the top complaints from smartphone users across every brand, every price point. Apple has made real strides with power efficiency through its custom chips, but raw capacity still counts. The iPhone 17 Pro Max already has solid all-day battery life for most people, but power users, travelers, and anyone stuck in back-to-back meetings know it can feel tight by evening.
A jump to 5,391 mAh, combined with whatever efficiency gains come from the next-generation chip expected in the 18 series, could push the Pro Max into genuinely impressive territory. Android flagships like the Samsung Galaxy S25 Ultra have been pushing 5,000 mAh and beyond for a while now, so Apple closing that gap would be a smart move.
There’s also a broader trend here. Phone makers across the board are prioritizing bigger batteries right now, partly because consumers are demanding it and partly because AI features are eating more power than ever. Apple is not immune to that pressure.
Still, one leaked battery label doesn’t confirm anything. But if the 18 Pro Max does land with a 5,391 mAh cell, that’s a headline feature Apple will absolutely lead with.