Battery health issues with iOS 18.0.1 on iPhone 15promax

In October the 9th I had 97% battery health and after not even a month (on the 28th October) my battery health went down to 94%. Anyone knows why ? I haven’t been using my phone more or charging it more than usual.

using an iPhone 15 pro max.

This is really concerning !!! 3% in less than a month?

Battery health issues with iOS 18.0.1 on iPhone 15promax
 
 
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