Abstract: A method of operating a PEM fuel cell including an anode feed circuit and a cathode feed circuit for feeding of an anode side with a reactant gas and for feeding a cathode side with a cathode gas. A shut-down mode for shutting down an electricity generating operation of the fuel system includes decreasing the supply of reactant gas and cathode gas in response of a shut-down signal, monitoring an output voltage of at least one cell of a fuel cell stack, monitoring the reactant gas pressure and the cathode gas pressure, electrically shunting of the at least one fuel cell in response of the output voltage reaching a predefined voltage level, at least reducing the pressure of the anode side to a predefined pressure level by means of at least one pump, and filling and/or flushing of at least the anode side with an inert gas.

Abstract: The method for limiting the output voltage of a PEM fuel cell system operating in, or near, zero load conditions, in such a way as to minimize degradation of performance over time, comprises: supplying a hydrogen stream to the anode of the fuel cell; supplying an oxygen stream to the cathode of the fuel cell; monitoring an output voltage of the fuel cell; monitoring a hydrogen pressure in the fuel cell; monitoring an oxygen pressure in the fuel cell; limiting the hydrogen stream and the oxygen stream while actuating controllable recirculating pumps for the hydrogen and the oxygen in such a way as to bring and maintain the hydrogen and oxygen pressures below 1 barabsolute while maintaining the hydrogen pressure between 70 and 130% of the oxygen pressure, so that the output voltage remains below 0.90 volts.

Abstract: The present invention relates to an inertial separator for gas liquid separation, comprising: a tubular body (12) having an inlet (14) extending through a sidewall of the body (12) substantially in tangential direction, an annular duct (16) arranged inside the tubular body (12) and being in fluid communication with the inlet (14), wherein the annular duct (16) extends into an interior chamber (18) of the tubular body (12) via an annular gap (20) extending between an inside facing side wall portion (15) of the body (12) and a first insert (30; 50).

Abstract: The fuel cell system includes: at least one fuel cell adapted to generate electrical energy from a fuel gas and an oxidizer gas; a fuel feed duct provided for supplying the fuel cell with fuel gas, the fuel feed duct including an upstream part and a downstream part; a Venturi effect ejector including a high pressure inlet, a low pressure inlet and an outlet, the upstream part of the fuel feed duct being connected to the high pressure inlet of the ejector and the downstream part extending between the ejector outlet and the fuel cell; an off-gas recirculation duct extending between the fuel cell and the low pressure ejector inlet so that, in the presence of a stream of fuel gas coming from the upstream part of the fuel feed duct and passing through the ejector, the ejector draws up off-gas from the recirculation duct and ejects it into the downstream part mixed with the stream of fuel gas coming from the upstream part; a control circuit and a valve arranged in the upstream part of the fuel feed duct and arra

Abstract: The present invention concerns a separator plate for use in a fuel cell stack with a substantially circular or oval main surface wherein a fluid flow path is defined by a plurality of channels extending substantially in parallel to each other and leading a fluid from a fluid supply port to a fluid discharge port. Adjacent channels merge such as to decrease the number of parallel channels from the supply port to the discharge port, thereby decreasing a cross sectional area of the flow path.

Abstract: A method of operating a PEM fuel cell including an anode feed circuit and a cathode feed circuit for feeding of an anode side with a reactant gas and for feeding a cathode side with a cathode gas. A shut-down mode for shutting down an electricity generating operation of the fuel system includes decreasing the supply of reactant gas and cathode gas in response of a shut-down signal, monitoring an output voltage of at least one cell of a fuel cell stack, monitoring the reactant gas pressure and the cathode gas pressure, electrically shunting of the at least one fuel cell in response of the output voltage reaching a predefined voltage level, at least reducing the pressure of the anode side to a predefined pressure level by means of at least one pump, and filling and/or flushing of at least the anode side with an inert gas.

Abstract: The method of operating a passive hybrid power supply in, or near, zero connected load conditions comprises the steps of: supplying a stream of substantially pure hydrogen to the anode of the fuel cell; supplying an stream of substantially pure oxygen to the cathode of the fuel cell; monitoring an electric current supplied by the storage battery; monitoring an output voltage shared by the fuel cell and the battery; evaluating a state of charge (SOC) of the battery based on the electric current and the output voltage; monitoring a hydrogen pressure in the fuel cell; monitoring an oxygen pressure in the fuel cell; limiting the stream of hydrogen and the stream of oxygen and actuating the hydrogen and oxygen recirculating pumps in such a way as to bring and maintain the hydrogen and oxygen pressures below 0.7 barabsolute while maintaining the hydrogen pressure between 70 and 130% of the oxygen pressure, in such a way as to ensure that the output voltage is maintained at a level corresponding to less than 0.

Abstract: The method for limiting the output voltage of a PEM fuel cell system operating in, or near, zero load conditions, in such a way as to minimize degradation of performance over time, comprises: supplying a hydrogen stream to the anode of the fuel cell; supplying an oxygen stream to the cathode of the fuel cell; monitoring an output voltage of the fuel cell; monitoring a hydrogen pressure in the fuel cell; monitoring an oxygen pressure in the fuel cell; limiting the hydrogen stream and the oxygen stream while actuating controllable recirculating pumps for the hydrogen and the oxygen in such a way as to bring and maintain the hydrogen and oxygen pressures below 1 barabsolute while maintaining the hydrogen pressure between 70 and 130% of the oxygen pressure, so that the output voltage remains below 0.90 volts.

Abstract: The present invention concerns a separator plate for use in a fuel cell stack with a substantially circular or oval main surface wherein a fluid flow path is defined by a plurality of channels extending substantially in parallel to each other and leading a fluid from a fluid supply port to a fluid discharge port. Adjacent channels merge such as to decrease the number of parallel channels from the supply port to the discharge port, thereby decreasing a cross sectional area of the flow path.