A state detection device for fuel cell includes a supposed high-frequency impedance value setting unit configured to set a supposed high-frequency impedance value on the basis of an impedance measurement value belonging to an arc region of an impedance curve of the fuel cell, an actually measured high-frequency impedance value calculation unit configured to obtain an actually measured high-frequency impedance value on the basis of an impedance measurement value belonging to a non-arc region of the impedance curve of the fuel cell, and an ionomer resistance estimation unit configured to estimate a value obtained by subtracting the actually measured high-frequency impedance value from the supposed high-frequency impedance value as an ionomer resistance value. The supposed high-frequency impedance value setting unit sets a value of an intersection of an equivalent circuit impedance curve set on the basis of the impedance measurement value belonging to the arc region and a real ads as the supposed high-frequency impedance value.

A fuel cell internal state detection system includes estimation object state quantity setting unit for setting a suitable estimation object state quantity as an index of an internal state, an impedance value acquisition unit configured to obtain an impedance value of a fuel cell, an impedance usability judging unit configured to judge whether or not the obtained impedance value is usable for the calculation of the estimation object state quantity, estimation object state quantity calculation unit for calculating the estimation object state quantity set by the estimation object state quantity setting unit on the basis of the obtained impedance value when the impedance value is judged to be usable for the calculation of the estimation object state quantity by the impedance usability judging unit, and an unusable-scene process execution unit configured to perform an unusable-scene process when the impedance value is judged not to be usable for the calculation of the estimation object state quantity by the impedance usability judging unit.

A fuel cell system includes a fuel supply unit that supplies a fuel to electrolyte membrane of fuel cell, an oxidant supply unit that supplies an oxidant to the electrolyte membrane, and an electricity generation control unit that controls electricity generation by the fuel cell by controlling supply of the oxidant by the oxidant supply unit and supply of the fuel by the fuel supply unit. the fuel cell system includes a wet/dry state detection unit configured to detect a wet/dry state of the electrolyte membrane, a flow rate adjustment unit configured to adjust a flow rate of the fuel supplied to the fuel cell by the fuel supply unit; and a temperature adjustment unit configured to adjust a temperature of the oxidant supplied to the fuel cell by the oxidant supply unit. when reducing an amount of water in the electrolyte membrane in accordance with a signal output from the wet/dry state detection unit, the electricity generation control unit is configured to reduce the flow rate of the fuel, and increase the temperature of the oxidant in accordance with the signal from the wet/dry state detection unit, compared with when increasing the amount of water in the electrolyte membrane.

A fuel cell stack assembly comprises a stack of fuel cells, each fuel cell having an air flow conduit with an input/output ventilation aperture disposed on a ventilation face of the stack, the ventilation apertures forming an array over said ventilation face of the stack. A membrane is moveable between a first configuration in which the ventilation face is occluded and a second configuration in which the ventilation face is not occluded. The membrane is rollable between the first configuration and the second configuration. Ventilation of the fuel cell stack is thereby controlled by the position of the membrane, e.g. during fuel cell start up and/or shut down procedures or for hydration control of the fuel cells.

A fuel cell system includes a fuel cell, a first actuator capable of adjusting a first state quantity indicating an internal state of the fuel cell, a second actuator capable of adjusting a second state quantity indicating the internal state of the fuel cell, and a control unit. The control unit is configured to perform a first control and a second control, the first control includes acquiring a present value of the first state quantity and controlling operation of the first actuator so that the acquired present value of the first state quantity approaches a predetermined first target value, and the second control includes acquiring a present value of the second state quantity and controlling operation of the second actuator so that the acquired present value of the second state quantity approaches a predetermined second target value.

A fuel cell system includes a gas supply passage configured to supply one of the anode gas and the cathode gas to the fuel cell, a refrigerant supply apparatus that supplies refrigerant for cooling the fuel cell to the fuel cell, a heat exchanger that exchanges heat between the refrigerant increased in temperature by the fuel cell and the gas supplied to the gas supply passage. The fuel cell includes a component that circulates the one of the anode gas and the cathode gas discharged from the fuel cell to the fuel cell, and a warm-up control unit that controls a flow rate of the refrigerant to a predetermined flow rate for warming up the fuel cell when the fuel cell is warmed up. The fuel cell system includes a gas temperature increase control unit increases the flow rate of the refrigerant to be supplied to the heat exchanger on the basis of a temperature of the gas circulated by the component or a parameter related to the temperature when the flow rate of the refrigerant is controlled by the warm-up control unit.

A fuel cell system for supplying anode gas and cathode gas to a fuel cell and causing the fuel cell to generate power according to a load includes a component that circulates discharged gas of either the anode gas or the cathode gas discharged from the fuel cell to the fuel cell. The fuel cell system includes a power generation control unit that controls a power generation state of the fuel cell on the basis of the load, a freezing prediction unit that predicts the freezing of the component on the basis of a temperature of the fuel cell system. The fuel cell system includes an operation execution unit that executes a warm-up operation without stopping the fuel cell system or after the stop of the fuel cell system in the case of receiving a stop command of the fuel cell system when the freezing of the component is predicted.

A method for adjusting an output of a fuel cell system is capable of estimating a dry state of a fuel cell vehicle by comparing air flow rates, and adjusting a maximum output applicable to the fuel cell vehicle, thus enabling the fuel cell vehicle to be stably driven. The method for adjusting the output of the fuel cell system includes comparing an air flow rate required for driving and an actually introduced air flow rate to calculate an average air flow rate, and calculating an available output of the vehicle using preset mapping data with respect to the average air flow rate.

Systems and methods for initiating voltage recovery procedures in a fuel cell system based in part on an estimated specific activity over the life of a fuel cell catalyst are presented. In certain embodiments, SA loss of catalyst and electrochemical surface area loss of a FC system may be estimated. An output voltage of the FC system may be estimated based on the estimated SA loss and the electrochemical surface area loss. An amount of recoverable voltage loss may be determined based on a comparison between the estimated output voltage and a measured output voltage. Based on the determined amount of recordable voltage loss, a FC system control action (e.g., a voltage recovery procedure) may be initiated.

An apparatus and a method for controlling a humidification amount of a membrane humidifier for a fuel cell are provided. The humidification amount of the membrane humidifier relative to air supplied to a stack is changed by adjusting a difference in partial pressure of moisture between the inside and the exterior of a hollow fiber membrane that constitutes the membrane humidifier for a fuel cell.