Battery level indicator stuck after charging

wildoil

Quite frequently, my phone's battery charge indicator gets stuck after charging the phone overnight. As in, the phone finishes charging, I take it off the charger and use it, but the battery indicator acts like it's still charging, even after an extended period of use. The battery percentage stays the same, and the Battery page in the settings says "Done charging" instead of "Not charging", even though the phone is off the charger.

This started happening a month or so ago, and has persisted after several updates. It doesn't happen every time I charge my phone, but I've seen it happen multiple times per week.

I use the 80% charge limit, and with that, it's obvious when the charge indicator gets stuck, because the battery indicator stays green (like it's still charging), and has a shield icon that shows up when the phone is done charging to 80% with the limit on.

I thought this only happened at the 80% limit, but last week my phone charged to 100%, and got stuck there, too.

This seems to be a bug in how battery percentage is reported, and not every battery statistic as a whole. The OS still "knows" the voltage decreasing. When I run termux-battery-status (or use an app like Castro), I see the same percentage being stuck there, too (e.g. 80% earlier today), but I do see voltage decreasing when I run the command multiple times. I don't know if the bug is GrapheneOS specific, or comes from upstream AOSP, and if it's specific to my phone (Pixel 9 Pro XL), or affects other devices. When searching for it, I found this post from a few years ago, where someone's battery indicator was stuck at 100%, but their description of the problem does not exactly match what I see.

Workarounds that get the charge level indicator working again:

Restarting the phone (frustrating to do, as having to restart so often is a chore, and the reboot process itself eats up some battery)
Use the "Battery share" feature, and try to charge another device off my phone (like my headphones case) — doesn't fix it completely, only when I take the other device off my phone

tl;dr: battery charge indicator gets stuck after charging, has persisted after multiple updates, the only real workaround is rebooting the phone.

Novaliss

wildoil
This thread is similar.
https://discuss.grapheneos.org/d/20620-charging-optimization-80-charge-limit-recalibration-with-android-15-qpr2/141

What model is your device?
Update; now I see it in your post.

spammerofspam

wildoil I've got the same issue and the same phone model.

Are you using wireless charging? I am.

DeletedUser733

wildoil

Whether its a similar problem or not, my 8a charges to 100%, then when its taken off charge, it stays at 100% for hours at a time. No matter what use it gets.
The battery app graph is completely useless and is blank. After a few hours I reboot the phone and the battery icon on the lock screen will show what appears to be the correct level.
I have given up using the battery app.
I neither charge using wireless or use the battery optimization charge to 80%, its all done via USB and when the phone is switched off.
The phone has been like this for several weeks/months and through several updates.

wildoil

spammerofspam yes, I primarily wireless charge overnight.

spammerofspam

wildoil Another random question, do you have a magsafe-type case on your phone?

I'm wondering if some update tweaked the Qi charger presence detection, and it's somehow now confused that the magnets in my case are a charger.

I guess I could try charging without the case as an experiment, but if it's happening to you without such a case I'll probably have my answer without doing the experiment.

wildoil

spammerofspam yeah, I do have a case with a Magsafe ring. I'm sceptical that that's the issue, but worth a try!

spammerofspam

wildoil I do not think it's related to the case. My phone had the stuck shield icon today. The shield was still stuck after removing the case.

Novaliss

spammerofspam still only wireless charging?

wildoil

Happened again today (wireless charging, yes), and I found another workaround that doesn't require a restart.

With the charger disconnected, go to battery settings and turn off "Charging optimization -> limit to 80%"
- The status bar will no longer show the green battery + shield icon, but the Battery settings page will show "Connected, but not charging". (This is obviously wrong, since there's no charger connected)
Now connect the charger again. The phone will realize it's actually charging now, and will say "done charging by [time]"
Disconnect the charger, and feel free to turn the 80% limit back on

After that, the phone will report battery as draining and not charged, as expected. This obviously works only if you happen to notice soon enough when you still have a charger nearby.

I also don't know if the battery percentage will be completely accurate after this workaround, if you don't do it soon enough after charging. The time I tried the "charge another device from the phone" workaround, I noticed that the battery indicator started going down from 80% despite me having used the phone for some time before doing that. With the "restart the phone" workaround, the percentage always goes down quite a bit more off the bat.

Either way, I'm happy to have found an easier workaround that doesn't require restarting my phone. But I hope there's a real fix soon.

spammerofspam

After experimenting with this some more, I don't think it's related to the charging limit or wireless charging. I've disabled the 80% charging limit, and topped off my phone via wired charging. My phone has been at 100% for some time after removing the cable, and, at the Battery screen it says "Charged", as if it's still plugged in.

wildoil

spammerofspam

thanks for experimenting with this. I had suspected that neither the 80% charge limit nor wireless charging were actually related to this bug, but now we have a concrete data point.