12 volt in the truck bed setup

I’m looking to place a 12 volt plug in the truck bed so I can charge my goal zero battery while driving. It can pull up to 10 amps. I was thinking of using 10 gauge wire.

Initially I was planning to add a fuse tap on something that’s only on with the ignition but noticed all the add a fuse taps are 16 awg. Which I would think is going to be a problem when attaching a 10 gauge wire. I also read that it wasn’t ideal to add a fuse for something drawing a large current.

So idea #2 is to use a relay that’s connected to an ignition source and wire the 10 gauge wire to the battery.

What do you guys think is the best option?

 

Plan #2 is best plus allows for future expansion.

 

Probably a relay though I ve never messed with one. If you are concerned with having a 10 gauge wire tap, and all you can find is 16, why not replace the wire with 10 gauge, and use the appropriate fuse? I would think as long as you draw less than the hardware was designed for it would accomodate the reduction.

 

So I would need to solder 10 gauge wire to the fuse tap?