iPhone 15 has a curious new charging setting you might want to turn on

iPhone 15 Pro charging next to a Macbook, airpods, and an iPad
(Image credit: Apple)

The iPhone 15 and iPhone 15 Pro come with a brand new charging setting borrowed from Tesla that could extend the life of your battery by limiting charging to just 80% capacity. 

Apple’s new best iPhone hits the stores later this week, and as per usual, iPhone 15 reviews are starting to roll out, including from The Verge’s Allison Johnson. Johnson noted in a Q&A this week that the iPhone 15 and 15 Pro feature three options within Apple’s Charging Optimization settings. 

Users of the iPhone 14 and other devices will be familiar with Apple’s Optimized Battery Charging feature. “To reduce battery ageing, iPhone learns from your daily charging routine so it can wait to finish charging past 80% until you need to use it.” This existing feature is particularly useful for those who charge their iPhone while sleeping because it means your phone doesn’t reach 100% in the middle of the night and then just sits plugged in. However, with the iPhone 15, Apple is taking the feature one step further.

80% of the charge, it works every time 

Apple’s Battery Health & Charging settings now reportedly feature three options; Optimized Battery Charging, 80% limit, and none. The former is the aforementioned option that will charge your device fully, but only at the right time. The latter is unrestricted charging, but its that new second option we’re interested in. 

iPhone 15 and 15 Pro seem to have the option to put a hard ceiling on the charge capacity of your iPhone so that it never charges beyond 80%. But why? The answer is simple, and one that Tesla owners will know all too well, battery degradation.

Batteries degrade over time as they go through charging cycles, it takes a while, but there’s always a clear drop off in battery of the life of an iPhone as you use it. As Apple’s own website states, “As lithium-ion batteries chemically age, the amount of charge they can hold diminishes, resulting in shorter amounts of time before a device needs to be recharged.”

This has been particularly notable with the iPhone 14. My own iPhone 14 Pro is down to just 90% capacity after a year of use, and it’s possible Apple is hoping to extend battery lifespan and reduce degradation by limiting user charging to 80%. To be clear, you have to enable this setting, so it’s up to you whether you use it or not. But given problems with last year’s iPhones, I think a lot of users might consider this option, especially if the new and more efficient A17 Pro Bionic chip can see you through the day on an 80% charge. 

Stephen Warwick
News Editor

Stephen Warwick has written about Apple for five years at iMore and previously elsewhere. He covers all of iMore's latest breaking news regarding all of Apple's products and services, both hardware and software. Stephen has interviewed industry experts in a range of fields including finance, litigation, security, and more. He also specializes in curating and reviewing audio hardware and has experience beyond journalism in sound engineering, production, and design. Before becoming a writer Stephen studied Ancient History at University and also worked at Apple for more than two years. Stephen is also a host on the iMore show, a weekly podcast recorded live that discusses the latest in breaking Apple news, as well as featuring fun trivia about all things Apple. Follow him on Twitter @stephenwarwick9

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