Abstract: A method of moving an electrically powered mining machine between locations that have electric power supplies, the mining machine of the type having at least one electric motor for moving the mining machine, the method including connecting a temporary power unit to the motor on the mining machine and operating the power unit to selectively power the mining machine. The temporary power unit comprises at least one battery, and a relay for selectively making an electrical connection, a connector for connecting the relay to the battery pack, and a connector for connecting the relay to the electric motor for selectively connecting the battery to at least one electric motor on the mining machine to selectively power the electric motor to move the mining machine. At least one of the connectors is long and flexible to permit relative movement between the battery and the mining machine. The power unit also includes a remote control device for operating the relay.