iPhone 15 battery life is set to get a whole lot better — here’s why (report)

Rumored iPhone 15 Ultra may take the place of the Pro Max (iPhone 14 Pro Max shown)
(Image credit: Laptop Mag)

We love the iPhone, but battery life is a common complaint across all our reviews. Apple is set to tackle this problem with a huge hardware upgrade in the iPhone 15!

According to Twitter user “RGcloudS,” the company is moving the new iPhones over to a stacked battery technology, which will not only increase the energy capacity, but make the battery keep performing at its best for a whole lot longer too.

Stacking it

IPhone 15 render

(Image credit: N/A)

We’ve already seen a version of a stacked battery cell from Apple before, as the company layered battery slices to fit the contours of the previous generation MacBook Air.

But this is a lot more complex, folding the elements and separators into zig-zag layers, which uses significantly less space than the traditional method of rolling up the battery elements. Not only that but heat is dissipated more evenly across the whole battery — rather than getting super hot in a single area. That means you won’t feel one particular hotspot, and it elongates the cell's lifespan too.

This seems to tie in nicely with a reported leak of iPhone 15 battery capacities, which showed these increases over the iPhone 14 models:

  • iPhone 15: 3,877mAh (+15%)
  • iPhone 15 Plus: 4,912mAh (+12%)
  • iPhone 15 Pro: 3,650mAh (+12%)
  • iPhone 15 Pro Max: 4,852mAh (+11%)

That’s a big jump up, which is definitely needed. Each version of Apple’s own silicon may be getting some improvements in power efficiency, but there’s no avoiding the fact they get a little more power-hungry too.

For example, the iPhone 14 Pro's 3,200 mAh battery lasted 10 hours and 13 minutes on our Laptop Mag battery test. But while the iPhone 13 Pro had a smaller 3,095 mAh capacity, its A15 Bionic sipped the juice a lot slower with 12 hours on the same test.

Fuelling up

iPhone 15 Pro

(Image credit: 9to5Mac)

On top of this, there are claims that Apple is testing a far faster 40W wired charging, alongside 20W over MagSafe. Not only is the battery capacity set to increase, but you’ll be able to juice it back up to 100% a whole lot faster too. However, whether this faster charging will come to the iPhone 15 or iPhone 16 remains unclear.

One thing you’ve probably noticed across our iPhone 14 and iPhone 14 Pro reviews (not so much iPhone 14 Pro Max) is the underwhelming stamina leading to some battery anxiety. Apple needs to get a whole lot more aggressive with stuffing its phones with batteries. This leak seems to be an acknowledgment of that problem.

It will be interesting to see the end result of this reported battery expansion at the September event. Stay tuned to Laptop Mag for all the latest iPhone 15 leaks in the run-up to it!

Jason England
Content Editor

Jason brought a decade of tech and gaming journalism experience to his role as a writer at Laptop Mag, and he is now the Managing Editor of Computing at Tom's Guide. He takes a particular interest in writing articles and creating videos about laptops, headphones and games. He has previously written for Kotaku, Stuff and BBC Science Focus. In his spare time, you'll find Jason looking for good dogs to pet or thinking about eating pizza if he isn't already.