Charging laptop from 12-volt battery

cmcdar wrote:
PS: ANY appliance that has a little black box somewhere along the power cord, is really a 12v item. The little black box converts AC to DC.

... or 5V, or 6V, or 9V, or 15V, or 19V, or AC, something completely different. It's really bad advice to tell people all black boxes put out 12 VDC, because putting that into lots of devices will blow them up, blow a fuse, or best case they simply won't work.