Abstract: A fuel cell system includes a fuel cell, a control valve and a controller. The fuel cell is configured to receive anode gas and cathode gas to generate electric power. The control valve is configured to control pressure of the anode gas being fed to the fuel cell through an anode flow channel. The controller controls the control valve to periodically increase and decrease the pressure of the anode gas flowing through the anode flow channel in an area downstream of the control valve. The controller sets an anode pressure differential value for the anode gas resulting from periodic increasing and decreasing of the pressure of the anode gas based on a requested fuel cell output. The controller determines a quantity of liquid in the anode flow channel. The controller decreases the anode pressure differential value that was set based on the requested fuel cell output.

Abstract: A fuel cell system includes a fuel cell, a control valve and a controller. The controller controls the control valve to periodically increase and decrease the anode gas pressure downstream of the control valve. The controller executes a shutdown/restart operation of the fuel cell by closing the control valve to stop the anode gas and shutting down power generation of the fuel cell upon receiving a shutdown command, and restarting feeding of the anode gas and restarting the power generation upon a prescribed operation restart condition being met. The controller estimates an anode gas concentration at a location where the anode gas concentration is locally lower within a power generation region of the fuel cell based on a control state of the anode gas when the shutdown command is issued. The controller sets the prescribed operation restart condition for executing the shutdown/restart operation based on the anode gas concentration.

Abstract: A fuel cell system includes a fuel cell, a control valve and a controller. The controller controls the control valve to periodically increase and decrease the anode gas pressure downstream of the control valve. The controller executes a shutdown operation of the fuel cell by closing the control valve to stop the anode gas and shutting down power generation of the fuel cell upon receiving a shutdown command. The controller estimates an anode gas concentration at a location where the anode gas concentration is locally lower within a power generation region of the fuel cell based on a control state of the anode gas at a time the shutdown command is issued. The controller determines whether to permit or prohibit shutting down the power generating operation based on the anode gas concentration.

Abstract: A fuel cell assembly (1) is disclosed. The fuel cell assembly (1) has a fuel cell stack (2) formed by laminating a plurality of cells; plus and minus current extraction sections (4), the current extraction sections (4) extracting current generated by the fuel cell stack and sandwiching the fuel cell stack with respect to the direction of lamination; and a passage (4a) allowing flow of a fluid provided in at least one of the current extraction sections. Further a fuel cell system, which has the above fuel cell stack and a heating device (24, 26, 32, 90) for heating the passage for the fluid, is disclosed.

Abstract: A fuel cell assembly (1) is disclosed. The fuel cell assembly (1) has a fuel cell stack (2) formed by laminating a plurality of cells; plus and minus current extraction sections (4), the current extraction sections (4) extracting current generated by the fuel cell stack and sandwiching the fuel cell stack with respect to the direction of lamination; and a passage (4a) allowing flow of a fluid provided in at least one of the current extraction sections. Further a fuel cell system, which has the above fuel cell stack and a heating device (24, 26, 32, 90) for heating the passage for the fluid, is disclosed.

Abstract: A polymer electrolyte fuel cell stack is provided with a plurality of unit cells, a gas supply manifold supplying reaction gases to each of the plurality of unit cells, a gas exhaust manifold through which the reaction gases are exhausted, and a pressure loss control mechanism controlling the reaction gases passing trough the gas supply manifold, respective flow passages of the plurality of unit cells and the exhaust manifold to control pressure loss of at least one of the gas supply manifold and the gas exhaust manifold corresponding to the flow rates of the reaction gases in a way to establish a predetermined ratio between the pressure loss of at least one of the gas supply manifold and the gas exhaust manifold and pressure loss in the respective flow passages of the plurality of unit cells.