Makita 18v battery to car 12v socket

Holds a car power socket and a 5.5 x 2.5mm barrel jack. It does not need a buck converter if you choose your devices carefully. Large trucks run on 24v so most quality adapters are happy to function on 18v, I have tried all of my compatible devices including pumps.

The cigarette lighter socket seems to be a standard size, and you can get 100w type C adapters. Many choices on amazon.

The battery prongs are 8x100mm nickel strips folded and glued in place. Your socket will likely come with wires.