Some iPhone 11 , iPhone 11 Pro, and iPhone 11 Pro Max may show incorrect battery life data. iOS 14.5 includes a feature to fix this bug. Battery recalibration tare. This feature will automatically recalibrate the battery to display a more accurate percentage. It is even capable of letting us know if the battery needs to be changed (replacement will be free).
Therefore, if you have noticed that the maximum battery capacity is lower than it should be, you can go to Settings> Battery> Battery health and check if the iPhone is doing a recalibration. A warning will appear in the upper area and we can see the battery level in the lower part.