iPhone 16 Pro Max Battery capacity dropped 3% in a week

[zonai]

I regularly log my phone's battery capacity and cycles using CoconutBattery whenever I plug it in to offload photos or install an update. This week, I noticed something rather crazy: My 1-year-old iPhone 16 Pro Max went from a 98.7% battery capacity to 95.6% battery capacity--a drop of more than 3%-- in just 5 days, from last Wednesday to today. I went through 5 battery cycles in that time and am at 301 so far.

Granted, it's done better than my iPhone 15 Pro Max, which dropped to 89.1% battery health after 296 cycles (final reading), but does this seem normal to anyone? I was feeling pretty good about my 98% battery health until now.

 

[Basic75]

The percentage is only an estimate that is improved when you do a full charge cycle which allows the processor in the battery to calibrate its estimate with reality.

 

[joeblow7777]

Battery capacity is always just an estimate. Best not to worry about it until it's actually a problem. An apparent sudden drop of a few percent probably just means that it was being overestimated before.

An estimated battery health of 95.6% after 1 year and 300 cycles is actually very good and well on pace to exceed the expected 80% health after 1000 cycles or about 2 years.

 

[Jackbequickly]

Not to worry as when it gets to 80%, it will stop dropping. 😳