Abstract: A fuel cell system is provided that can suppress the degradation of the MEA and simultaneously assure the merchantability. The fuel cell system 1 includes: a fuel cell 10 that generates electric power by reacting hydrogen gas and oxidant gas; a temperature sensor 103 that detects the temperature of the fuel cell 10; a voltage lower limit calculation portion 31 that sets the voltage threshold to limit the output of the fuel cell 10 based on the temperature detected of the fuel cell 10; a current upper limit calculation portion 32 and the current limiting portion 33 that limits the output of the fuel cell in a case where the voltage generated by the fuel cell 10 is lower than the voltage threshold.

Abstract: A fuel cell system includes a fuel cell stack for power generation by electrochemical reactions of a fuel gas and an oxygen-containing gas, a high voltage energy storage capable of storing and discharging electrical energy generated by power generation of the fuel cell stack, and capable of being directly coupled to the fuel cell stack, a group of loads consuming at least electrical energy generated by the fuel cell stack or electrical energy discharged from the high voltage energy storage, and an auxiliary device control unit for reducing an amount of electrical energy remaining in the energy storage to a predetermined value by any of the group of loads, before starting power generation of the fuel cell stack.

Abstract: A fuel cell system which includes: a fuel cell having a fuel gas flow path and an oxidant gas flow path and generating electricity by being supplied a fuel gas to the fuel gas flow path and an oxidant gas to the oxidant gas flow path; fuel gas supplying means; a discharge valve; fuel gas exchange means for exchanging an atmosphere inside the fuel gas flow path for the fuel gas at a starting of the system; and cold start determination means for determining whether to conduct or not to conduct the cold start of the system, wherein when the cold start determination means determines to conduct the cold start, the cold start determination means increases a total discharge amount of a gas to be discharged for exchanging the atmosphere inside the fuel gas flow path for the fuel gas, and thereby increases a fuel gas concentration in the fuel gas flow path.

Abstract: The object of the present invention is to provide a fuel cell system enabling reliable startup thereof, even below the freezing point. The fuel cell system 1 is provided with a startup electric power calculation portion 71 for calculating electric power required for allowing an auxiliary device 50 to startup the fuel cell; an available electric power calculation portion 72 calculating the available electric power of the high voltage battery 22; and an auxiliary device electric power control means 73 for judging whether the available electric power exceeds the startup electric power, supplying electric power to the auxiliary device 50 to startup the fuel cell 10 when the available electric power is greater than the startup electric power, and cancelling startup of the fuel cell when the available electric power is not greater than the startup electric power.

Abstract: A fuel cell system including: a fuel cell which generates electrical power through the reaction of a reaction gas; a reaction gas supply device which supplies the reaction gas to the fuel cell; a cooling device which cools the fuel cell by circulating a coolant through the fuel cell; a fuel cell operating temperature output device which outputs a maximum temperature inside the fuel cell as an operating temperature of the fuel cell; and a fuel cell temperature adjustment device which adjusts a temperature inside the fuel cell so that the operating temperature inside the fuel cell is less than a preset upper temperature limit.

Abstract: This fuel cell system is equipped with a fuel cell having a reaction gas flow passage, generating power by the reaction gas being supplied to the reaction gas flow passage, having a refrigerant flow passage, and cooled by the refrigerant being supplied to the refrigerant flow passage; a reaction gas supply device for supplying the reaction gas to the reaction gas flow passage; a refrigerant supply device for supplying the refrigerant to the refrigerant flow passage; a refrigerant supply restriction device for restricting a refrigerant supply amount to the refrigerant flow passage; and a controller for controlling the refrigerant supply restriction device, wherein the reaction gas refrigerant supply devices have a drive device in common and are integrally driven, and wherein when warming up the fuel cell, the controller controls the refrigerant supply restriction device and reduces the refrigerant supply amount to the refrigerant flow passage.

Abstract: A fuel-cell system 1 includes: a fuel cell 13 configured to generate electricity through reaction between hydrogen gas and air; a compressor 12 configured to supply air as a scavenging gas to a reactant gas path 13a of the fuel cell 13; a control part 18 configured to control an amount of air supplied from the compressor 12 to the fuel cell 13 to perform scavenging of the fuel cell 13; and pressure sensors P1 and P2 configured to monitor a pressure drop in the reactant gas path 13a of the fuel cell 13. The control part 18 controls an amount of supplied air so as to keep the pressure drop in the reactant gas path 13a substantially constant when the fuel cell 13 is scavenged. With this configuration, residual water can be suitably purged from the fuel cell while energy consumption is suppressed.

Abstract: A fuel cell system is provided which estimates a water content in a fuel cell based on a predetermined map using an integrated value of electric current generated by the fuel cell (ST4) before power generation is stopped (ST5). When a temperature of the fuel cell has fallen lower than a predetermined value (ST7) after the power generation is stopped (ST5), the fuel cell system determines a dry degree in the fuel cell (ST8) and an anode scavenging period (ST9) based on predetermined maps. Scavenging is performed in an anode in the fuel cell for the anode scavenging period (ST10).

Abstract: A fuel cell system and a method for scavenging it are provided. The fuel cell system includes a fuel cell, a fuel gas passage, an oxidant gas passage, a communicating passage, a communicating valve, a monitoring device, a valve controller, a scavenging device and a computing device. The monitoring device monitors a state transition of the fuel cell after a termination of power generation. The valve controller opens the communicating valve when a signal indicative of the state transition meets a predetermined criterion. The scavenging device includes a first scavenging device for the oxidant gas passage, and a second scavenging device for the fuel gas passage. The computing device computes an amount of the oxidant gas required for scavenging according to a system shut off time. The scavenging device conducts scavenging with the amount of the oxidant gas obtained by the computing device.

Abstract: When it is detected that the ignition switch is turned off a short period of time after the ignition switch turned on at the temperature below the freezing point, the charge threshold of a capacitor is changed to a larger charge threshold C for increasing the amount of electrical energy charged in the capacitor based on the charge threshold C. The capacitor is used for performing a scavenging process for a sufficient period of time. At the time of starting operation of the fuel cell system at the temperature below the freezing point the next time, using the electrical energy of the capacitor, a fuel cell is warmed rapidly by a heater or the like to start operation of the fuel cell system.

Abstract: A fuel cell system wherein even if the fuel cell is exposed to a cold environment, stabilization of power generation is possible. The fuel cell system comprises: a fuel cell in which electric power is generated by a reaction of reaction gases; purging means for purging at least one of reaction gas flow paths through which reaction gases flow; thermal detecting means for detecting a temperature of the fuel cell; low-temperature determining means, which determines that the temperature of the fuel cell is low every time it is below a predetermined temperature; and purging control means for purging the fuel cell when the low-temperature determining means determines, after an input of a power generation stop signal, that the temperature of the fuel cell is low.

Abstract: A reaction gas is supplied to a cathode side of a fuel cell at a flow rate higher than that for a usual operation of the fuel cell to thaw the fuel cell system at startup in a freezing state of the system when the system has experienced a temperature lower than an operation temperature of an anode off-gas. A thawing state of the system is detected on the basis of at least two of temperatures of the anode off-gas, a cathode off gas, and a radiator liquid of the fuel cell to control supplying the reaction gas to the cathode side at a usual operation flow rate. An actual increase rate of the temperature of the anode off-gas is obtained and an increase rate of the temperature of the anode off-gas is calculated from the self-heating value to be compared to determine the thawing state.