My phone sometimes seems to sit at 70–80% forever, then race through the last 20%.
Is the battery actually draining faster near empty, or is the percentage mainly an estimate that gets less reliable with load, temperature and battery age?
Why can the last 20% of a phone battery seem to disappear faster?
- batteries
- phones
- technology
160
2 replies
One thing that confused me was that the drain still depends on what the phone is doing. A bright screen, weak signal, or a heavy app can mak...
One thing that confused me was that the drain still depends on what the phone is doing. A bright screen, weak signal, or a heavy app can make the last part go fast enough that it feels like the battery itself changed personality.
So it’s more that the meter is less trustworthy at the edges, plus the phone may be working harder, not that the battery chemistry suddenly becomes rude at 19%?
That’s how I’d put it, yes. The chemistry is still changing gradually, but the percentage display is doing a lot of estimation.
2 replies
Pretty much, yes. The battery percentage is an estimate, and the estimate gets shakier when the phone is under load or the battery is older....
Pretty much, yes. The battery percentage is an estimate, and the estimate gets shakier when the phone is under load or the battery is older. So the last chunk can feel dramatic even if it’s not a neat physical cliff.
I think the phone also uses protection behavior near empty, right? Like it may shut down before the number says zero, so the display and the actual usable charge are not perfectly lined up.
Yeah, that too. The phone is trying to avoid the awkward surprise of “0%” followed by “surprise, still on.”