A fuel cell system is provided and the fuel cell system includes: a fuel cell; a fuel processing unit configured to process a raw fuel to produce a fuel gas for the fuel cell; an oxidant gas heating unit configured to heat an oxidant gas for the fuel cell; a combustor configured to combust the raw fuel to produce a combustion gas for use in heating the fuel processing unit and the oxidant gas heating unit; a supply control unit configured to, during a warm-up of the fuel cell, control supply of the raw fuel to the fuel processing unit and the combustor; and a power generation control unit configured to control a power generation state during the warm-up of the fuel cell. When the fuel cell has reached a power generation available temperature, the power generation control unit is configured to cause the fuel cell to perform power generation, and the supply control unit is configured to supply the raw fuel to both the fuel processing unit and the combustor.

A method for humidifying a reactant in a fuel cell system is provided having a fuel cell stack, which is fluidically connected to a humidifier, wherein the humidifier comprises a membrane, on whose surface channels are formed. At least one of the channels is associated with a storage element for temporary storing of liquid water, the method involving the following steps: extracting the liquid water from the fuel cell stack and feeding the liquid water to the humidifier, admitting at least part of the liquid water into the storage element and temporarily storing the part therein, at least partially emptying the storage element by evaporating of the liquid water and humidifying of the reactant being supplied to the fuel cell stack by means of the evaporated liquid water, wherein the liquid water is extracted from the fuel cell stack both at the anode side and at the cathode side. A fuel cell system for carrying out the method is also provided.

A fuel cell system includes: a fuel cell that includes an installation port and a discharge port for a reactant gas; a first injection device that intermittently injects the reactant gas; second and third injection devices that continuously inject the reactant gas; an ejector that includes an ejection port for the reactant gas from the first or second injection device and the discharge port; a first flow passage that connects the installation port and the ejection port; a second flow passage through which the reactant gas from the third injection device is led to the first flow passage without the ejector; and a control device that performs a warm-up operation by executing the injection of the third injection device, executes the injection of the second injection device, and executes the injection of the first injection device after completion of the warm-up operation.

A fuel cell system includes a fuel cell, a circuit, a pump, a pressure regulating valve, and a control apparatus. The fuel cell includes a plurality of membrane electrode assemblies and a separator. The separator has a gas channel and a coolant channel. The circuit is coupled to the coolant channel and allows a coolant to circulate therethrough. The pump delivers the coolant toward the coolant channel. The pressure regulating valve adjusts a pressure of the coolant in the coolant channel. The control apparatus controls a flow rate of the coolant in the coolant channel by controlling a rotational speed of the pump on the basis of a temperature of the fuel cell, and controls the pressure of the coolant in the coolant channel by controlling a position of the pressure regulating valve on the basis of a pressure of gas in the gas channel.

A fuel cell system includes a fuel cell, first and second supply devices, a gas-liquid separator, a discharge valve, first and second ejectors for discharging fuel gas and off gas to the fuel cell, a measuring device for gas pressure, and a control device. The first ejector has a discharge amount smaller than the second ejector. The first ejector has a circulation amount larger than the second ejector. The control device executes the supply during a first time from the first supply device at each first cycle such that the pressure becomes a first target value, and when the first ejector is in an abnormal state, stops the first supply device, executes the supply during a shorter second time from the second supply device at each shorter second cycle such that the pressure becomes a higher second target value, and opens and closes the discharge valve at each first cycle.

Disclosed is a method of controlling an air supply system for a fuel cell. The air supply system includes a fuel cell stack, an air channel to supply air to an inlet of the fuel cell stack, a gas adsorption unit disposed on the air channel and configured to adsorb oxygen contained in air introduced into the air channel. In particular, the method includes: determining whether a power generation operation of the fuel cell stack is resumed; when the power generation operation of the fuel cell stack is resumed, controlling a voltage source to apply a voltage to the gas adsorption unit; and supplying air to the fuel cell stack through the air channel in a state in which the voltage is applied to the gas adsorption unit.

The fuel cell system includes: a fuel cell; an anode supply pipe; a fuel gas supplier disposed at the anode supply pipe, the fuel gas supplier configured to adjust a supply quantity of a fuel gas to be supplied to the fuel cell; an ejector disposed at the anode supply pipe at a position between the fuel gas supplier and the anode supply port; an anode circulation pipe connected to the anode discharge port and the ejector; a circulation stop unit disposed at the anode circulation pipe, the circulation stop unit configured to stop circulation of the fuel gas through the anode circulation pipe; a pressure sensor configured to detect a pressure in the anode supply pipe at a position between the ejector and the anode supply port; and a controller. When a first pressure acquired from the pressure sensor is equal to or less than a predetermined lower limit value, the controller controls the fuel gas supplier to perform constant quantity supply control to supply the fuel gas of a predetermined supply quantity, and controls the circulation stop unit to perform circulation stop control to stop the circulation through the anode circulation pipe, and the controller determines abnormality at the ejector and the anode circulation pipe by using a second pressure acquired from the pressure sensor after the fuel gas supplier performs the constant quantity supply control and the circulation stop unit performs the circulation stop control.

A fuel cell system includes: a fuel cell; a first valve device provided at an oxidation gas supply channel; a second valve device provided at an oxidation off-gas discharge channel; a third valve device provided at a bypass channel; an abnormality detection unit configured to detect an abnormality; and a control unit. The control unit causes the fuel cell to initiate fail-safe power generation if (i) a different abnormality from a valve opening abnormality is detected in the first valve device, (ii) the different abnormality is detected in the second valve device, or (iii) any abnormality is detected in the third valve device. During the fail-safe power generation, if any abnormality is additionally detected in any valve device different from the valve device in which an abnormality is already detected, the control unit stops power generation by the fuel cell.

When a time point of occurrence of a stop state of a fuel cell system is predicted during traveling, a drying state control that causes a fuel cell stack to transition to a dry state is started a predetermined time (a required drying time) before the predicted time point of occurrence of the stop state.

An ECU of a fuel cell system supplies cathode gas by rotating an air pump at a low-load rotational speed and performs a low-load power generation in a fuel cell stack, while a moving body is traveling. When the fuel cell stack generates power while the moving body is stopped, the ECU increases the supply amount of the cathode gas by rotating the air pump at a during-stoppage-of-traveling rotational speed which is greater than the low-load rotational speed.