The iPhone uses a non-genuine battery that will not see the battery status on iOS 11.3.
But if your iPhone uses a battery pack (a non-genuine battery) due to replacing batteries in non-Apple authorized stores, this feature will not work. The maximum capacity of the battery will not be displayed, along with the message "This iPhone cannot determine battery status" below.
In addition to the above situation, users can still use the iPhone with "lot" battery on iOS 11.3 without any other problems.
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