FUEL DEVICE AND THE USE THEREOF IN A MOTOR VEHICLE

The present invention relates to a fuel cell device () having a fuel cell () which, during operation, emits water as a product of cold combustion; a supply air path () leading to the fuel cell () for a cathode supply air flow (), which defines a supply air flow direction (), the cathode supply air flow coming from water-containing supply air supplied to the fuel cell (); and an exhaust air path ()leading away from the fuel cell (), for a cathode exhaust air flow (), which defines an exhaust air flow direction (), the cathode exhaust air flow coming from water-containing exhaust air flowing out of the fuel cell (). The supply air path () and the exhaust air path () are routed through a humidifier () of the fuel cell device (), which humidifier communicates fluidically with the supply air and the exhaust air, to humidify the supply air and dehumidifying the exhaust air. The exhaust air path () is also routed through a water separator () of the fuel cell device (), which water separator communicates fluidically with the exhaust air, for removing water from the exhaust air and for providing this water as evaporation water. The fuel cell device () also has a heat exchanger () for cooling the fuel cell (), which heat exchanger has an evaporative cooler () for cooling the heat exchanger (). It is essential that the evaporative cooler () is assigned to the water separator () in fluidic communication and that it is supplied with evaporation water by same.