Basically, this feature isn’t technically new as it was present with the first beta. With Beta 1, some users saw a notification that asked them if they wanted to enable the new charge limit, but users weren’t able to turn it off.
Beta 2 addresses that issue with preferences, and users can now choose to not use the 80% charging limits.
Now in the Battery section in Settings, you have a new “Charging optimization” menu which appears after the first time you plug in. Adaptive Charging, which is a feature similar to Apple’s Optimized Battery Charging and which stops charging at 80% to then finish at 100% an hour before you usually unplug, is joined by “Limit to 80%”.
This new feature basically does just as expected: it allows your phone to only charge the battery to 80% and not more.
You may wonder why would you need to enable such a feature to begin with. Well, it should technically extend your phone’s battery lifespan, and protect your battery from degrading as fast as it would without the feature.
So far, Google has not yet updated its Pixel support documents to detail the battery charging limit. We expect Google to update the documentation once the Android 15 QPR1 launch happens in December.
Basically, this protection is based on the behavior of lithium-ion batteries and the fact that when you charge a battery up to 100%, the cells in the battery are put under significant stress, which could make the battery degrade more over time.
I think that this protection is great and I always like it when companies work for the longevity of your phone instead of pushing you to go get a new model once this one is done. So, kudos to Google for working on this feature!