A materials handling device includes a chassis, handle shaft pivotally
mounted to the chassis for maneuvering the device, two rollers
rotationally mounted to the chassis, battery pack supported on the handle
shaft, electric motor and gearbox fitted in one roller in-line with a
rotational axis thereof, and a controller supported on the chassis and
having capacitors charged by the battery pack so as to have available
when needed a store of electrical power. The controller is electrically
connected between the battery pack and electric motor such that the store
of electrical power can be supplied to the electric motor which, via the
gearbox, can transmit a high torque driving output, when needed and
instantaneously, to the one roller to thereby enable the device to move
across a surface and to manipulate and move a heavy load.