A post on Reddit has highlighted a new behavior in iPhone charging overnight. User @nathan_lesage reported that his iPhone 13 turned off itself for four hours during an overnight charge, and magically rebooted itself before his morning alarm went off.
A quick search on Google revealed that it is not unusual for iPhones to turn off by themselves because of multiple reasons like old battery, maxed-out memory, or iOS version as per a thread on Apple Community from 2022.
However, what makes this incident stand out is the fact that the iPhone turned on itself and several other users are experiencing the same behavior.
Could Apple backport the iPhone 15’s 80% charge limit option to older models?
Before the launch of the iPhone 15 series, several iPhone 14 users reported rapid decline in battery health only within a year. Probably to increase the battery lifespan in the iPhone 15 models, Apple introduced a new 80% limit for Optimized Battery Charging feature.
If the battery charge level gets down to 75 percent, charging will resume until your battery charge level reaches about 80 percent again.
With 80% Limit enabled, your iPhone will occasionally charge to 100 percent to maintain accurate battery state-of-charge estimates.
When enabled, the feature stops charging the device at 80% to improve the lifespan of the battery by preventing full 100% charge. However, the feature is exclusively availble on iPhone 15 models which upset alot of iPhone users.
Coming back to latest report, the charging behavior described by users shows that Apple might be backporting the iPhone 15’s Optimized Battery Charging 80% limit option to older models.
What it also did which I have never seen before: it only charged to 80% and then stopped for about two hours prior to switching itself off. I never observed this behavior on the 13 yet. Also, while it was off it apparently charged further until 100%.
What sets me off especially is that it has been off for four hours: I would’ve just said it’s a bug if it restarted within a minute or so, but why would it stay off for four hours and then just magically boot about half an hour prior to my alarm going off? wrote nathan_lesage
Other added that their iPhones running on iOS 17.0.3 showed the same charging behavoir.
@Daimie wrote: Mine too with iOS 17.0.3 wrote
@NemoJones wrote: Same. iOS 17.0.3 iPhone 14 Pro Max. Spooky.
I agree with the posters who said it wasn’t off for the whole time — my graph shows it started tracking battery after I entered my passcode. My alarm went off and I was prompted for passcode this morning as the phone had restarted.
@xVisenya wrote: My 13 pro max did that too this night.
The upcoming iOS 17.1 update, currently in the beta testing phase, does not bring the new Optimized Battery Charging 80% Limit to older iPhones. Plus, it is unlikely that Apple would test a feature on older iPhone models like this. Therefore, it is likely a bug impacting the iPhone’s charging behavior.