In a passive hybrid topology, the fuel cell is directly electrically coupled to the battery. Although no DC/DC converters are used, it is possible to control the fuel cell power by adjusting its operating pressure, and thus the power sharing between the fuel cell and the battery becomes actively controlled. Using this concept, simulations results show that the power demand of an electric vehicle is fulfilled while sustaining the battery state of charge. By removing the DC/DC converter, the hybrid system becomes simpler, lighter and cheaper.