You would first need to verify the voltage/amperage requirements of the torch. My old W/E Pilot whale has a three cell carrier with a built in switch. The cells mount in PARALLEL for the carrier, so 3.7 volts only, for three cells. Your HID may require more voltage to help the circuitry facilitate a strike. I have heard of others opening original packs and replacing cells, but that may be opening a can of worms, so to speak. Its
a shame, cause the ' BOXER' is a really nice, underated torch. Sorry, i know thats not much help. The other route may be a custom made battery, but how far do you go?