I have seen several "gadgets" that plug into the cigarette lighters, and run off of a vehicles 12v dc power. I am wondering if anyone has ever tried any of these. Specifically, any of the 12v slow cookers, dc tv, and vcr. I'm curious about what affect they have on the vehicles battery too. Anyone?
Depends on so much
So much depends on your battery, the size of the wiring, the alternator, etc. Any one of those gadgets could be fine, so long as you are driving. I would not put on multiple gadgets which draw heat, without having a second battery installed. I have also been told, and learned at a cost, that idling the engine does not do it. I have a house battery in my conversion van, to run the refrigerator.
There is a lot of information about using 12v electrical devices in this forum.