All four iPhone 15 models have two new battery health features in the Settings app, including the ability to view the battery's cycle count and an option to more strictly limit charging beyond 80%. On social media, some users hoped these features would expand to older iPhone models in a future software update, but we are able to confirm that they remain limited to the iPhone 15 lineup as of the first iOS 17.1 beta released today.
It's early in the iOS 17.1 beta testing cycle, so there is still a chance the features are added to older iPhone models in a later beta. However, it's also possible there are hardware-related reasons behind the battery health features being limited to the iPhone 15 lineup. We've reached out to Apple for comment on the matter.
On iPhone 15 models, the 80% charging limit option can be found in the Settings app under Battery → Battery Health & Charging → Charging Optimization. It is separate from the pre-existing Optimized Battery Charging feature on iPhones, which intelligently delays charging past 80% until a more appropriate time by learning the device's daily charging routine. When the 80% limit is enabled, the iPhone will never charge beyond that percentage, except on rare occasions to "maintain accurate battery state-of-charge estimates."
In a support document, Apple says reducing the time that an iPhone battery is fully charged can reduce the wear on the battery and improve its lifespan.
On iPhone 15 models, the battery's cycle count, manufacturing date, and first use date can be viewed in the Settings app under General → About. This information can provide additional insight into the health of the battery. The battery's maximum capacity remains listed under Battery → Battery Health & Charging.
iOS 17.1 is expected to be released in late October.
Source: Macrumors