iPhone 14 pro max battery health at 99% a month after purchase

Battery Health & Performance 

Your battery health is fine and is undergoing normal usage. iPhone batteries, like all rechargeable batteries, are consumable components that become less effective as they age. You should change out the battery once your Battery Health reaches below 80% which will take over 2 years to reach under normal usage. Until then enjoy your iPhone.

Here is some more reading on an iPhone battery and its performance ➡️ iPhone Battery and Performance - Apple Support

Axel F.  

krzysztof2706 Said:

"Battery: battery health a month after purchase from 100% to 99% is this normal? iphone 14 pro max"

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Battery Heath Depletion:

Yes. This is normal behavior. Unfortunately, there is no way to know how, nor when, the Battery Health percentage decreased. Apple recommends you get a new battery when the Battery Health reaches 80% or less.

Do not ignore it but don’t worry about it. As time elapses you will have to monitor the Battery Capacity Percentage until it reaches 80%. That is the time you change the battery. Will take about 2 years.

Axel F.

The battery health measurement process is not an exact science and its rather a process of approximation. This means that there is no set amount of percentage that the battery will degrade every month, however, it will degrade and eventually will get reported.

Axel F.