Every iPhone user is concerned with battery life, and for good reason. Our phones are our everything these days, and when the battery dies we feel cut off from the world and unable to capture the moment. With the iPhone 15, Apple is providing a new option to help increase battery longevity–not how long a single charge lasts, but to reduce the natural degrading common to all rechargeable batteries.
In iOS 13, Apple added a new Optimized Battery Charging feature that, when enabled, looks at your past iPhone use history to pause charging at 80 percent when the system determines you’re unlikely to need more than that before you charge again. That’s nice, but you’re still leaving it up to the system.
With the iPhone 15 (all models, including Pro), there’s an additional choice in Settings > Battery > Battery Health & Charging > Charging Optimization. The new 80% Limit option will stop your iPhone from charging when it reaches 80 percent of full capacity, all the time, every time.
In addition, you can open Settings > General > About and find a new Battery section that shows your battery’s manufacture date, date of first use, and cycle count. This could be useful information for those getting third-party repairs or replacements for their batteries, or deciding some years down the line if the battery needs replacing. All iPhones record this data, but you have to use third-party apps to easily read it or jump through some hoops like pasting your iPhone Analytics Data into Notes and sifting through it. This could be especially useful after the iPhone 14 Pro Max appeared to suffer abnormal battery degredation.
Why would a person want to limit charging to 80 percent? Well, rechargeable batteries degrade over time through normal use and are able to hold less charge, which means shorter battery life. They degrade much faster when under extreme thermal stress, and when kept in a fully-charged state.
For example, this is why all modern electric cars encourage drivers to limit charging to 80-90 percent for daily driving and provide settings to do so, with full 100 percent charging only for longer trips.
Users like me who work at a desk with ready access to a charger and rarely drop below 40 percent on a typical day would be better off setting a hard charge limit of 80 percent, as long as they remember to turn it off on those days when they’re likely to have a heavy-use day away from the charger.
It is, of course, just an option—like Optimized Battery Charging, it can be enabled or disabled at will to give users more control over battery life and longevity.
The only question we have is: why is this useful feature limited to iPhone 15 models? Surely there are plenty of existing iPhone owners who would appreciate this option in a software update, and it seems trivial enough to implement. Maybe we’ll see it in iOS 17.1.