Abstract: A fuel cell system including a fuel cell stack having cathode and anode sides, a housing surrounding the fuel cell stack, a housing purging air inlet, an air-conveying installation disposed on the housing purging air inlet, a housing purging air outlet, an oxidation catalyst, a temperature sensor, and a control unit. The air-conveying installation continuously directs an airflow into the housing purging air inlet. The oxidation catalyst is disposed downstream of the housing purging air outlet and catalytically combusts hydrogen and oxygen. The temperature sensor is disposed on the oxidation catalyst and detects the oxidation catalyst temperature as an information item pertaining to a volumetric hydrogen flow occurring outside a fuel cell process and to be discharged. The control unit couples to the temperature sensor and to the air-conveying installation and receives the temperature detected by the temperature sensor and to therefrom determine variations of a hydrogen concentration.

Abstract: A fuel cell system includes a fuel cell stack, a housing, a first coolant port, a second coolant port, and a cooling device having a coolant pump and a heat exchanger in fluid communication with the coolant pump. The housing includes an upper side and a bottom side. The fuel cell stack is arranged inside the housing. The first coolant port and the second coolant port each comprise a coolant tube having an inner tube, an outer tube and a gap therebetween. Each of the first coolant port and the second coolant port reach through the housing in a way that an inner end is further to the upper side than an outer end. The first coolant port and the second coolant port are coupled to the cooling device and a first coolant path of the fuel cell stack to form a coolant loop.

Abstract: A fuel cell power system including at least one fuel cell, a ram air system and a cooling circuit in which coolant is intended to circulate for regulating a temperature of the at least one fuel cell. The cooling circuit comprises a ram air heat exchanger in the ram air system and the ram air system comprises a nozzle. The fuel cell power system further comprises a water tank and the fuel cell power system is arranged to flow water from the water tank to the ram air system so as to spray water in ram air via the nozzle. Thus, dimensioning of the ram air system which includes the ram air heat exchanger is reduced.

Abstract: A fuel cell power system including at least one fuel cell, a ram air system and a cooling circuit in which coolant is intended to circulate for regulating a temperature of the at least one fuel cell. The cooling circuit comprises a ram air heat exchanger in the ram air system and the ram air system comprises a nozzle. The fuel cell power system further comprises a water tank and the fuel cell power system is arranged to flow water from the water tank to the ram air system so as to spray water in ram air via the nozzle. Thus, dimensioning of the ram air system which includes the ram air heat exchanger is reduced.