Sudden rapid decrease in battery health

[super chimp]

My iPhone 11 Pro in the last week has lost the same amount of battery health that it lost in the 12 months before that with it now reducing to 80%. I’ve owned a lot of iPhones over the years and of the models that have had the battery health monitoring I’ve never had one lose so much battery percentage in such a short time. My iPhone is on iOS 15.1.

Is it likely to keep losing battery health at such an accelerated rate and does it mean there’s something seriously wrong with the battery?

 

[chabig]

If the battery health is reported below 80% in less than two years, Apple will replace it for free.

 

[super chimp]

If the battery health is reported below 80% in less than two years, Apple will replace it for free.

Just my luck then that my iPhone is coming up to two years and two months old.

 

[now i see it]

Battery degradation isn’t linear.
My iPhone 7 battery health is at 83% and if I turn it off at 60% charge, two weeks later it’s completely dead to the point that the date resets to 1969.

An iPhone battery at 80% health (according to iOS) really is on its last leg. In reality it’s more like 10%

 

[Fred Zed]

Battery degradation isn’t linear.
My iPhone 7 battery health is at 83% and if I turn it off at 60% charge, two weeks later it’s completely dead to the point that the date resets to 1969.

An iPhone battery at 80% health (according to iOS) really is on its last leg. In reality it’s more like 10%

They were the good ole days ( weren’t they?) when the cells used by manufacturer appeared to be more superior to the current gens. Either that or and fast charging is more common causing devices to degrade quicker than before. When most had 5W chargers. Just a wild guess.

 

[super chimp]

They were the good ole days ( weren’t they?) when the cells used by manufacturer appeared to be more superior to the current gens. Either that or and fast charging is more common causing devices to degrade quicker than before. When most had 5W chargers. Just a wild guess.

I owned my iPhone 6S+ longer than this phone so far & when I eventually upgraded the battery health was still at 81%.

 

[super chimp]

Battery degradation isn’t linear.
My iPhone 7 battery health is at 83% and if I turn it off at 60% charge, two weeks later it’s completely dead to the point that the date resets to 1969.

An iPhone battery at 80% health (according to iOS) really is on its last leg. In reality it’s more like 10%

I’ve been wondering if it’s the weekly fairly long Teams meeting I’ve been having the last three months or so as that seems to really hit the battery life that has finished the battery health off.