"Error Type: Abnormal Powerdown" indicates that device lost power at some moment, probably at some point while booting.
Than it is obvious hardware problem.
In device is circuit which controls charging battery and also powering device from battery when there is no external power supply.
Problem could be (and probably is) in this circuit. But again, without physical measurements it's impossible to find exact source of problem.
If you can live with this situation than it is better to leave as it is, otherwise you have to find qualified person to repair it.