Battery "jump packs"

dockmasterdave wrote:
I have one of these in the tt for emergency jump starts, and have used it to run tv and ant booster in a pinch.
My question would be, if it is used, can it be recharged from my tow vehicle?
Can I make up a cord to go from the 12 volt receptacle on the jump pack, to a 12v accessory outlet in the truck?
Would I need to use a small inverter to charge it via the 120 plug?
I appreciate any opinions and look forward to the gurus setting me straight.

The short answer is: YES.. You can, in fact some of them come with what at 120 volts is called a "Suicide cord" (Double male) you can also buy cords already made up like this.

If there is room in the battery area you can clamp them to the main battery while driving as well but this does not always work as well

NOTE it may take a lot of driving to fully charge it.. HOURS.