You may have to see about recalibrating the battery...
•Apple Portables: Calibrating your Computer's Battery for best performance
But if the system management controller has corrupted you may need to reset it...
Learn to identify if this would be a path to consider, as there are other options first.
•Intel-based Macs: Resetting the System Management controller (SMC)
Some other settings are hiding in places such as NVRAM (PRAM in older Mac)
so you may go through a few things to sort this out. Or, Troubleshooting.
Good luck & happy computing!