About 80% Limit with iPhone 15 models
With iPhone 15 models, you can choose between Optimized Battery Charging, 80% Limit, and None.
When you choose 80% Limit, your iPhone will charge up to about 80 percent and then stop charging. 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.
If Optimized Battery Charging doesn't activate
Optimized charging is designed to engage only in locations where you spend the most time, such as your home and place of work. The feature doesn't engage when your usage habits are more variable, such as when you travel. Because of this, some location settings must be enabled for Optimized Battery Charging to activate.* None of the location information used for this feature is sent to Apple.
To improve the lifespan of your battery, your iPhone learns from your daily charging habits.
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