wheels 16 the engine 12 includes a transmission a differential device and the like assembled thereto which are not shown and a rotational output of the engine 12 is transmitted to the front wheels 16 through the transmission the differential device and the like the vehicle 10 includes an ecu electronic control unit which is not shown the ecu obtains a variety of information such as operating states of accelerator and brake pedals which are not shown vehicle speed and a charged state of a battery 30 which will be described later and arbitrarily controls the engine 12 the transmission and the like based on the information in the meantime it should be noted that the engine 12 is not limited to the gasoline engine a generator 20 is provided at a side of the engine 12 the generator 20 generates power by rotational forces input from the engine 12 or front wheels 16 the battery 30 is provided at a central part in the underfloor space the battery 30 is a battery that drives the vehicle 10 and has a relatively high capacity the power generated in the generator 20 is stored in the battery 30 in the meantime it may be possible that the generator 20 is driven by power from the battery 30 to rotate the front wheels 16 or to start the engine 12 the vehicle 10 includes at the rear portion a sub frame 50 including the rear wheel electromotor 14 assembled thereto fig2 shows the sub frame 50 as shown in fig2 the sub frame 50 has a substantially rectangular shape and includes tubular members 52 and 54 which are main pipes provided at both sides of the vehicle 10 a front cross member 56 provided at the front portions of the.