Pixel's 80% Charge Limit Bug
Android 15 QPR1 (December Pixel Drop) introduced a beneficial 80% charge limit feature to extend battery lifespan. However, this limit doesn't function when the Pixel phone is powered off.
The new toggle in the Battery settings lets users limit charging to 80%, theoretically reducing battery wear and tear. This feature, common in other phones, addresses the finite lifespan of batteries affected by heat and charge cycles. See how other OEMs are handling battery life.
Unfortunately, the 80% limit is ignored when the phone is off. If your Pixel's battery dies and you plug it in, it will charge to 100%. This suggests the limit is controlled by the Android system and not at a lower level. Check out how other Android phones handle charging limits.
While most users keep their phones on, this issue affects those who power off their devices. Some phones automatically power on when plugged in, but Pixels remain off until manually turned on. Compare this to other phones' charging behavior.
To maintain the 80% limit, power on your Pixel shortly after plugging it in.