My cable came with banana plugs, so I soldered little 90-degree wires so that it would connect to the DC-DC converter. Make sure to insulate them!

If you don't want to (or are not allowed) to solder, unscrew the banana plugs and strip the small red wires going to the plugs.

For those of you going the ghetto route, solder two pieces of wire to the positive and negative terminals where the battery would connect to the control board.