The newest iPhones always have a raft of fun and useful new features, but they don’t do much good if your phone doesn’t last through the day. That’s why Apple has been adding battery-saving features to iOS for years—and there’s one you should start using.
A quick caveat: this feature is currently limited to iPhone 15 models but there’s no reason Apple couldn’t bring it to older iPhones in iOS 18 or an iOS 17 update. If you have one of Apple’s newest phones, you’ll find a new 80% Limit option inside the Charging Optimization tab in the Battery Health & Charging settings. And if you haven’t already turned it on, you should.
Apple introduced the concept of Optimized Battery Charging in iOS 13. Powered by machine learning, it tracks your daily charging habits to “reduce the wear on your battery and improve its lifespan by reducing the time your iPhone spends fully charged.” When turned on, Optimized Battery Charging will periodically limit charging to 80 percent when you don’t need a full charge to help keep your battery healthy longer.
On the iPhone 15, you can take Optimized Battery Charging one step further by opting to always limit charging to 80 percent. That means your iPhone will essentially treat 80 percent as 100 percent and stop charging when it reaches 80 percent. If the battery charge level gets down to 75 percent, charging will resume until your battery charge level reaches about 80 percent again.
Why would you want that? Quite simply, it’ll make your iPhone’s battery last longer, especially if you have a habit of charging it often. For one thing, a lower percentage means fewer full charging cycles and a longer lifespan. Also, a lower charge percentage means your battery is less likely to reach extreme temperatures.
When I traded in my iPhone 14 Pro after just a year, the battery health was at 90 percent, so you can see how the battery can quickly degrade even after just a short time. So if you have an iPhone 15, flip it on and test it out for a few weeks.
Author: Michael Simon, Executive Editor
Michael Simon has been covering Apple since the iPod was the iWalk. His obsession with technology goes back to his first PC—the IBM Thinkpad with the lift-up keyboard for swapping out the drive. He's still waiting for that to come back in style tbh.