Do not use solder. It won't hhold. (tried it) Some auto parts stores have repair kits. Google Frost Fighter repair kit. It is a conductive epoxy. I've used it and it has held for many years of slamming a heavy hatch (other vehicle)
2003 TJ, 33" BFG AT, 2" BL, 2" BDS spring lift, Truck Lite headlights, Homemade sunrider top.