Cigarette Lighter Power Supply

[BrianG]

The problem I've seen with several cig lighters is that even though they are rated for 10A, they use fairly thin wires and you'll get some voltage drop which might be too low for the charger.

If a power jack in the rear of the vehicle is what you want, how about picking up a cheap amplifier install kit and running the wire? Something 10G or larger should be fine. It usually comes with everything you need depending on how you want.