iPhone battery life has come a long way over the past few years, and currently our list of the best phone battery life features two members of the iPhone 15 series — the iPhone 15 Plus and iPhone 15 Pro Max. But future iPhones could offer even better battery life thanks to a new design that could offer more energy density.
This news comes from long-time analyst Ming-Chi Kuo over on X. Kuo claims that Apple will be adopting a stainless steel casing for the iPhone battery, which will increase the cell density by around 5 to 10%. Apparently this will keep the battery within safety limits, while also complying with new EU rules.
This new battery will supposedly be added to some of this year’s iPhones, with Kuo previously claiming that the iPhone 16 Pro Max will be “a major beneficiary” of the denser batteries. That means Apple could offer better battery life with the same battery size, or trim down the battery to offer something similar to the iPhone 15 Pro Max.
Kuo noted that stainless steel isn’t as effective at dissipating heat, compared to the current aluminum design, meaning Apple will need to come up with a solution. However, it will offer better protection for the battery. A leaker back in April tipped the battery sizes for every iPhone 16 model, which you can see below.
| Row 0 - Cell 0 | iPhone 15 | iPhone 16 (rumored) | Percentage difference |
| Standard | 3,349 mAh | 3,561 mAh | +6% |
| Plus | 4,383 mAh | 4,006 mAh | -9% |
| Pro | 3,274 mAh | 3,355 mAh | +2% |
| Pro Max | 4,422 mAh | 4,676 mAh | +5% |
It’s unclear whether other iPhone 16 phones will get the same benefits, or if they will be stuck with similar batteries to the iPhone 15 series. According to one of Kuo’s previous reports, we may not see a full series rollout until the iPhone 17 — and the adoption will all depend on how well the new batteries are received.
The distinction could be important if only the new batteries are designed to comply with EU rules. Coming into force next year, those rules state that phone owners should be able to replace their batteries with basic and accessible tools.
That currently isn’t the case with the iPhone 15, since it requires specialized tools, a “battery press” and a pair of adhesive strips that need to be carefully removed with tweezers — because breaking them means your only option is to use solvent.
A recent report from The Information, detailed by MacRumors, claims that Apple will be simplifying this process with something called “electrically induced adhesive bonding," This will allow the battery to be dislodged with an electrical charge, rather than the current awkward method.
We’ll just have to wait and see what happens once the iPhone 16 Pro Max is released. Because there’s a reasonable chance we won’t find out about the new battery tech until the first iPhone 16 Pro Max teardowns hit the web.
In the meantime, be sure to check out our iPhone 16 and iPhone 16 Pro Max hubs for all the latest news and updates.
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