A fuel cell hybrid electric vehicle (FCHEV) is more advantageous compared to a gasoline-powered internal combustion engine based vehicle or a traditional hybrid electric vehicle (HEV) because a FCHEV only uses one electric motor instead of an internal combustion engine or an electric motor in combination with an internal combustion engine. This study proposes a novel fuel cell (FC)/supercapacitor (SC) hybrid power source to be utilized in FCHEVs. The power source includes a 90 kW proton exchange membrane fuel cell (PEMFC) stack used as the main power source, and a 600 F SC bank used as the auxiliary energy storage device. A prototype of the FC/SC hybrid power source has been constructed, and experimental verifications are presented that explicitly substantiate having a power efficiency of 96.2% around the rated power, highly accurate DC-link voltage regulation and producing an appropriate three-phase stator current supplied to the traction motor by using PWM technique are the main contributions of this work. Providing a maximum speed of 158 km/h, 0-100 km/h acceleration in 12.2 s and a cruising range of 435 km for a FCHEV with the weight of 1880 kg are the other advantages. The proposed FC/SC hybrid power source is also compared to the state of the art of all kinds of power sources used in FCHEVs that clearly demonstrates its better performances such as higher power efficiency, speed and acceleration.