Hello friends, i've posted a comment before in this thread and has been following all the new comments written here. Those users telling others to reset their iphone to restore that 1 or 2% battery health loss, please STOP.
Please let me elaborate more about Li-ion batteries. These batteries will decay/degrade over time. It is a scientific process that is inevitable and unavoidable. Your smartphone battery WILL degrade, it just depends on how fast or slow. An industrial grade battery tester that can accurately calculate the capacity of a li-ion batt is bigger than your iPhone itself, so yes, the accuracy for the battery measurement in our iPhone is very limited.
Your li-ion battery starts decaying the very moment you hit your 1st full charge cycle, albeit insignificant. So over the course of 1 or 2 month, it is NORMAL to lose 1 or 2%. For day to day typical consumers like most of the users here, there is NO WAY to reverse this decaying process as it is a scientifically normal process for li-ion battery. So no, your 'restore iPhone to get back to 100%' method will not work, because what's gone is gone.
Some info about wireless & fast charging below.
There are too many sources for me to cite, but these are the general ideas about li-ion batteries.
Higher temperature will cause li-ion batteries to degrade even faster, so yes wireless charging hurts the battery, albeit slowly and gently.
Charging with the new 18W charger is generally safe. 0 - 50% - super fast
50-80% - normal
80-95% - slow
95-100% - super slow
This adaptive charging helps prolong the life of your battery as it's not constantly pushing high wattage into your battery.
Obviously, the slower your charging, the better is it for your battery. But is it worth it to wait up to 4 hours (or possibly more) using the 5W charger to hit 100% for your iPhone 11 Pro Max, or a good 2 hours using the 18W charger, your call.
Another tip: the recommended power input for fast charging on iPhone is 18W. If you're gonna purchase a 3rd party charger, do not buy anything above 18W.
Anything below that like 5W, 10W, 12W etc chargers are fine. I've used a charger higher than 18W, and it's super fast. But it was what costed me 2% battery health. It's been a month since i switched back to the Apple 18W charging and there hasn't been any percentage drop.
