I had a Skil 12v Ni-cad drill/driver for many years and it served me well for various heavy construction projects around the garden and house. Problem was that eventually the Ni-cad cells wouldn't hold much charge. So I stripped the battery packs down and re-built them with new Ni-cads. It worked perfectly for a day or two them the gearbox just broke apart and was not repairable. I still have 20 Ni-cads sitting in a box waiting for a project.
I replaced it with a Bosch 18V 4Ah Li-on drill/driver which is superb. I can drive a 6mm xx 150mm screw through a fence post like it was made of butter.
I suspect if I used it as a leg winder I could jack up the van completely