Hi bennyboi and welcome to the forum,
I can’t answer your question but I cannot see why you couldn’t do what you asked about with a small low powered inverter perhaps via the auxiliary socket.
But just a word of warning if the 12volt battery gets low you may not be able to start the car as it appears, it is the 12v battery that wakes the systems in the car up to get the car going off the main drive battery
I have seen several reports on these forums where people unknowingly have been sat waiting for only a short while with radios and heaters going and have run the 12v battery down and had then not been able to start or drive the vehicle some say if you are sitting waiting with things switched on to keep the car switched fully on in the ready mode also as the 12v battery recharges from the main drive battery if you do this
So as I said this is just a warning for you, maybe have a chat with your dealer or look or search the forums about flat battery or unable to start the car hope this helps
Les