Abstract: An electric power unit for two-wheel vehicles comprising a batteries housing, from which current is supplied to a DC magnetic motor that is connected to a controller assembly, and a chain transmission driven by the DC magnetic motor, which is adapted to actuate a driven wheel of a two-wheel vehicle. The latter has a frame to which the electrical power unit for two-wheel vehicles is attached. The batteries housing incorporates a structure having two outwardly open compartments between which a hollow zone is interposed. Each of the two outwardly open compartments is divided in several partitions. Each of the several partitions is adaptable to receive one of several rechargeable batteries that are provided with terminals for contacting a wiring. Each of the two outwardly open compartments is provided with air channels air for heating the several rechargeable batteries.