Guess what the OP was referring to is what the plane guys refer to as a zip charger. Literally a pr of wires of certain length and guage attahed to car batt and the batts you want to charge. I misread when I saw the word charger. A pr of wires is not a charger, its a pr of wires, lol. You can search RCGroups in the battery/charger thread and prob figure out how to do this.

Plane guys use them to charge a123s since zip charging can't seem to hurt
a123s with high current.