For optimisation of the service life of the high-voltage battery of your MINI electric vehicle, it is preferable to charge at AC charging stations and Wallboxes with the maximum possible charging power of 11 kW or 22 kW or at DC charging stations with charging powers of up to 50 kW. MINI recommends a state of charge of between 10 and 80 percent.
MINI how-to video: https://youtu.be/gTbrkHwoLxc