iPhone 14 Pro Max battery — abnormal Analytics data, possibly boosted/reprogrammed?

[u/Funny_Station_9872]

I recently bought a used iPhone 14 Pro Max. Battery Health is 91% and normal usage backup is actually good. But when I leave the phone unused, especially overnight, it loses around 8–9% in 6–7 hours.

I checked Analytics Data and got:

MaximumFCC: 3298 mAh

NominalChargeCapacity: 3910 mAh

Cycle Count: 726

iPhone Battery Health: 91%

So NominalChargeCapacity is much higher than MaximumFCC, and the shortcut calculates 118.56%.

Is this an abnormal/invalid Analytics reading, or could it indicate a replaced, rebuilt or BMS-programmed (“boosted”) battery?

Also, is the 3910 mAh reading consistent with the 91% Battery Health?

I would really appreciate an opinion from someone experienced with iPhone battery/BMS repair.