Hi,

I changed the settings in the battery settings, turned my phone off and was trying the new feature to charge the battery to only 80%, but it didn't work. When I looked after some time on my phone, the charging was at 98%.
I was charging my phone, when it was turned off like I said and the charger and cable was not the "official" Google one. Although nobody said, that charging the battery to only 80%, only works with the Google charger and Google cable.

Any ideas why it's not working?

    This is just speculation but when u say "turned my phone off" do you mean completely shutting it down?
    There is a chance that the limit wouldn't work switched off. I pretty sure the limit is controlled via the OS and not the firmware. This would mean the 80% limit is not applied and the phone charges to 100% as it normally would.

      dendereTI9070 it's an OS feature. If the phone is turned off, the OS isn't loaded and the PMIC just charges the battery at will. Most people don't turn their phones off, even when charging. This is why you're probably one of the few to notice.

        • phnx

          • Post #4
          • Edited

          Yes, it is an OS feature and therefore will inherently not work when the phone is powered off. The stock implementation has the same limitation. Source. The only way around this would be for Google to implement it in the firmware.

          edit: splattergames' response hadn't appeared for me but I'll leave my answer here since it refers to the same limitation in stock with a source.

          • Iiii

            • Post #5

            When the phone is turned on and plugged in, I have noticed that even when bypass charging is active on my Pixel 6a, the battery status alternates between "CHARGING" and "NOT_CHARGING", even when using the OEM charger and OEM USB C cable.

            termux-battery-status (link) can be used to query for battery status, and the shield icon in the status bar should indicate that battery charging is on:

            it has bypass charging to use power directly from the charger without going through the battery. It shows the shield icon while doing this.

            From https://discuss.grapheneos.org/d/18611-grapheneos-version-2024123000-released/63

              collector Yes, I meant I completely turned off the phone. But well, it seems like it's not the fault of the GrapheneOS-Team, judging by the article linked by the user @phnx : https://9to5google.com/2025/01/02/psa-pixel-80-charge-limit-doesnt-work-while-your-device-is-powered-off/ .
              Although would have been nice if the GrapheneOS-team mentioned it somewhere...or maybe an official reply here from the GrapheneOS-team? I mean just so we have an official confirmation.

                This only applies while the OS is booted into the regular boot mode. The OS configures charging to work this way. There's nothing which can be set to make it happen without the OS booted. When the device is off, it normally boots into the OS charging mode when plugged in unless it's at an extremely low battery level near 0%. In theory, the OS could implement this charge limit there. It's not currently something implemented by the stock OS or at a low-level by the Android Open Source Project. It's not something we currently plan to add unless the stock OS adds it.

                iii When the phone is turned on and plugged in, I have noticed that even when bypass charging is active on my Pixel 6a, the battery status alternates between "CHARGING" and "NOT_CHARGING"

                Confirmed with "CPU Info" app in Pixel 6. Every few minutes it changes to charging for a few seconds.

                    • Dde0u

                      • Post #10

                      doublefree Every few minutes it changes to charging for a few seconds.

                      Is this behavior observed also on Google's stock OS?

                          4 days later

                          doublefree This is pure speculation but my guess is that this is intended behavior in order to ensure that the battery stays at 80% over time as the battery would otherwise slowly discharge over time when bypassed.

                            The "Charging Optomization" also states that it will "occasionally charge to 100% to recalibrate estimated capacity". Curious what "occasionally" actually means.