Why is my HTC One M7 not displaying the correct battery percentage?

[AC Question]

So ever since the 6.0 Lollipop update, my HTC One has been really weird with displaying the battery percentage. Let me clarify that it DOES charge. I know this because when I charge it overnight, it will be at 100% in the morning. Other times, I could charge it for an hour while it says 50% and it will still be at that percentage an hour later. However, if I restart the phone a few times or wipe the cache partition, it will sometimes fix itself and display the correct percentage. It's confusing, and I'm not sure how to describe it perfectly, but it's really annoying.

Does anyone have any solutions for me? Please don't tell me to try a factory reset, because I already did that and it solved nothing. I'm not sure what to do.

 

[Rukbat]

If the phone is rooted, you can try Battery Calibration (Root). Charge it until it stops charging (by watching the app - it comes with instructions). Then have the app set it for 100%.

It could also be flaky measurement code, not updating until you restart or wipe the cache. That's been reported on a few phones on a few versions of Android.