| Unless your Pixel 4a is from Verizon (locked), keep it. Unlock the bootloader, then install LineageOS, MindTheGapps, and Magisk. Once you have Magisk stabilized, install the Advanced Charging Controller, and configure it to halt charging at 80%. That should solve your problems, and turn the updates back on. I don't think there is a way to make Google Pay work in this configuration, which is a drawback. I can put all the URLs here if you ask. Edit: https://lineageos.org/ [I did not remember that Lineage hosts gapps images] https://wiki.lineageos.org/gapps/ [IIRC, the APK is renamed to a ZIP and flashed with recovery, then name it back and install the app] https://github.com/topjohnwu/Magisk/releases/tag/v28.1 https://magiskmanager.com/ https://github.com/VR-25/acc/releases/tag/v2023.10.16 |
As for charge limiting... limit at 80% is an okay workaround (certainly better than no limit at all!), but it's far from perfect. Namely, with this approach, charge controller chip doesn't know cut-off is coming, and will shove several amperes into the battery until last second, thus overshooting safe voltage level. This wears the battery (less so than with no limit, but still more than necessary).
Battery charging limiting should be done by voltage: this way, controller chip knows where to stop, so it makes soft taper-off at the end of charge cycle, by gradually nudging current down to stay within voltage envelope.
Charging profile could be observed from a rooted adb console:
(depending on phone model and firmware, some tweaking might be required to find/grep to get the right battery status file)