I’ve had my iPhone 13 Mini for over a year and when I was at Star Wars Celebration it went from 100% battery health to 99%, almost a year but it finally dropped. Since then it’s fallen off a cliff and just a month later I’m at 96%. It happens, I’m just surprised how quickly it’s falling off. I don’t use MagSafe to charge so really curious if this is normal. Apple say to replace at 80% so I’m good in terms of time left but it’s curious.
Anyone else notice this?
LJPUK 
2 responses to “iPhone battery health degradation”
Maybe that is why mine dropped.They redid the calculation maybe.
I’ve had my IPhone 13m two months. I’m a light user, it was at 100% until I let it update from 15.7 to 16.4, within days it went to 99%.