I was just doing random stuff on my phone and went to click a button near the top right of the screen, and was mildly horrified to see “1%”, so I immediately put it into the charger, where the phone promptly started showing “0%” for the next ~30 seconds. The phone never died.
Has this happened to any of you?
Yup. Battery percentages are an abstraction over the actual voltage and remaining amp-hours - it’s a complex formula which requires calibration and can easily be a bit off.
On one of my first smart phones, after replacing the battery with a much bigger one (both capacity and physically) it would still use the old formula, so it said 100% when halfway charged and after fully charging, during use it would stay near 0 (or at it - can’t remember well) for half the actual usable time. I found an app that could show the actual voltage in the notifications, which helped a lot. (When it went under 3.5 or something, I knew it was almost out) But that number also varied with how much power was being drawn, etc.