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iPhone 18 Pro Max could get a massive battery capacity upgrade

You’ll love how big the iPhone 18 Pro Max battery may be, according to a new leak

The back of an iPhone 17 Pro Max, laying down on a white table.
iPhone 17 Pro Max. | Image by PhoneArena
There’s a growing chance for the iPhone 18 Pro Max to steal the show from the first foldable iPhone Ultra during Apple’s September event. The latest reason is a sketchy but exciting new rumor about the battery capacity on the top-tier slab model.

iPhone 18 Pro Max may get a massive battery upgrade


Apple could bump the battery capacity of the iPhone 18 Pro Max with up to 8.5 percent, according to a leak on social media, reported by Macworld. The bigger of the two iPhone 18 Pro models could get a 5,235 mAh battery on the Nano SIM model and a massive 5,425 mAh on the eSIM version.

These numbers could mean that the Nano SIM version of the new model will see an 8.5% battery capacity increase over the iPhone 17 Pro Max and its 4,832 mAh cell. The eSIM version’s bump would be more modest, but still an impressive 6.6%, compared to last year’s model.

What improvement would make you consider buying an iPhone 18 Pro Max?
5 Votes


Questionable sources



As exciting as it is, this is among the sketchiest iPhone rumors we’ve seen in a while. Coming from a since-deleted tweet by an unknown leaker going by the name fireuniverse, the rumor was taken by a few media outlets, despite not having a specific reliable source.

The same leaker has also tweeted a screenshot from a Weibo post by a user whose name translates from Chinese to “Duo Ge Internet Technology” and has a photo with what are probably the two batteries of the iPhone 18 Pro Max. Both cells have their capacities marked, and the text in the post complains about the 190 mAh battery capacity lost to the Nano SIM inside the Chinese version of the phone.

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Neither Fire Universe, nor Duo Ge Internet Technology has a previous track record, but the information they’ve shared makes sense and matches much more reliable sources. Back in February, reputable Weibo leaker Digital Chat Station reported that the Chinese iPhone 18 Pro Max will surpass the 5,000 mAh battery mark, with the US version reaching over 5,200 mAh.



The new leak also comes right along with the data breach suffered by Apple supplier Tata Electronics, which is the source of several major and legitimate leaks. Its numbers also match the pattern of the earlier leaks.

A great talking point for Apple



If these are the final numbers, Apple will have a lot to brag about with the iPhone 18 Pro Max. Those will put it firmly ahead of the Galaxy S26 Ultra, and slightly ahead of the Pixel 10 Pro XL. Considering the rumored battery downgrade for Google’s new phones, it’ll also beat the Pixel 11 Pro XL.

Probably more important for Apple users would be the battery life improvements. One Reddit user said their iPhone 17 Pro Max was lasting them about two days despite only charging it up to 80% and never letting it go below 20%. While that user was “not impressed” with the performance, others said it was insane, awesome, or had the best battery life of any phone they’ve used.

Combined with the new, cooler, and more efficient A20 Pro chipset, the larger battery should last noticeably longer than last year. In his in-depth review of the iPhone 17 Pro Max, my colleague Preslav found that its battery lasted an estimated 7:46 hours, which is already a great result.

That would still keep iPhones very far from the giant batteries used in their Chinese competitors. While that won’t matter for the US buyers who don’t have access to devices like the Xiaomi 17 Ultra and the Oppo Find X9 Pro, it could be crucial for consumers in the second most important market for Apple.

Everything is great, except the price


Considering the price hikes, I thought I'd skip an upgrade this year, but the iPhone 18 Pro Max could change my opinion. A more efficient chipset, the iOS 27 improvements, and the larger battery are convincing enough, especially for someone with an aging device.
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