Abstract: A system for adjusting temperature of cooling-liquid comprises: a radiator; a cooling-liquid circulation flow-channel; a radiator bypass flow-channel; a thermostat valve; and a valve bypass flow-channel through which the cooling-liquid of the radiator bypass flow-channel is allowed to flow in a predetermined amount even if the thermostat valve is completely closed.

Abstract: A fuel cell system includes a fuel cell having an anode, a cathode, and an electrolyte membrane disposed therebetween. An oxidant gas supplying device supplies oxidant gas to the cathode, an oxidant gas backpressure regulating device regulates the pressure of the oxidant gas at the cathode according to a valve opening, and a pressure detecting device detects the oxidant gas pressure at the cathode. During a start-up fuel gas disposal process, a controller controls the oxidant gas supplying device to supply the oxidant gas at a standard oxidant gas flow, controls the valve opening of the oxidant gas backpressure regulating device to a first valve opening, and controls the valve opening of the oxidant gas backpressure regulating device to a second valve opening which is greater than the first valve opening when the oxidant gas pressure detected by the pressure detecting device reaches an elevation target pressure.

Abstract: A fuel cell system includes: a fuel cell stack (S) formed by stacking multiple unit cells (C) horizontally and having, in the stacked body, manifolds through which to supply and discharge reaction gases to and from each of the unit cells (C); and drainage paths (1A, 1B) extending from an anode-off-gas discharge manifold (M), on both end sides of the fuel cell stack (S) in the stacking direction of the unit cells, respectively.

Abstract: A fuel cell system is provided with a fuel cell, a gas supply passage which supplies a reaction gas to the fuel cell, a humidifier which humidifies the reaction gas, a first gas discharge passage which leads from a first gas discharge outlet of the fuel cell through the humidifier to the outside, and a second gas discharge flow passage which leads from a second gas discharge outlet of the fuel cell to the outside. A flow rate control mechanism which controls the flow rate of discharge gas is provided in at least one of the first gas discharge passage and the second gas discharge passage. The configuration reduces the distance between the fuel cell and the humidifier to obtain a compact system structure.

Abstract: The present invention provides a fuel cell system having means for controlling the flow of coolant within a fuel cell system. A desirable rate of flow of coolant is created, during power generation, by determining the difference in temperature between coolant flowing into individual cell sets of the fuel cell assembly and the temperature of coolant exhausted from the cell assembly. The fuel cell system features controls adapted to evaluate the heat generation state of each fuel cell set and to regulate the temperature of cell sets by controlling the rate circulation of the coolant.

Abstract: At shutdown of a fuel cell system, a system-shutdown controller is configured to cause a current extraction device to extract current from a fuel cell in a state where a supply of a fuel gas through a fuel supply system is continued and a supply of an oxidant gas through an oxidant supply system is stopped, and the system-shutdown controller is configured to airtightly close fresh-air control valves after increasing pressure of the fuel gas in a fuel electrode to not less than atmospheric pressure and not less than pressure of the oxidant gas in an oxidant electrode.

Abstract: Deterioration at the start-up and deterioration during the leaving period are suppressed in a good balance. As a system shutdown process, a controller (30) causes consumption of the air (oxygen) present in an oxidant electrode of a fuel cell stack (1) (oxygen consumption control). Further, after the termination of the oxygen consumption control, the controller (30) performs control to set a medium pressure hydrogen valve (13) and a hydrogen pressure adjustment valve (14) in a closed state. The controller (30) thereby causes hydrogen to be held in a passage located between the medium pressure hydrogen valve (13) and the hydrogen pressure adjustment valve (14). During a system shutdown period, a predetermined amount of hydrogen (medium pressure hydrogen) held in the hydrogen supply passage (L1) at a position between the medium pressure hydrogen valve (13) and the hydrogen pressure adjustment valve (14) can be supplied to the fuel electrode of the fuel cell stack (1) through a bypass passage (L2).

Abstract: A fuel cell system includes a fuel cell having an anode, a cathode, and an electrolyte membrane disposed therebetween. An oxidant gas supplying device supplies oxidant gas to the cathode, an oxidant gas backpressure regulating device regulates the pressure of the oxidant gas at the cathode according to a valve opening, and a pressure detecting device detects the oxidant gas pressure at the cathode. During a start-up fuel gas disposal process, a controller controls the oxidant gas supplying device to supply the oxidant gas at a standard oxidant gas flow, controls the valve opening of the oxidant gas backpressure regulating device to a first valve opening, and controls the valve opening of the oxidant gas backpressure regulating device to a second valve opening which is greater than the first valve opening when the oxidant gas pressure detected by the pressure detecting device reaches an elevation target pressure.

Abstract: For implementing a stop control which extracts a current from a fuel cell and consumes a cathode side oxygen at a system stop, the current extraction from the fuel cell is ended in a state that a certain quantity of oxygen smaller than when the current extraction is started remains on a cathode side of the fuel cell. With this, the hydrogen movement to the cathode side after the system stop can be effectively suppressed and thereby a cathode internal hydrogen concentration at the system start can be kept low, thus making it possible to properly process the cathode side hydrogen at the system start.

Abstract: A fuel cell system having a fuel cell, a coolant supply device for circulating a supply of the coolant through a coolant path for cooling the fuel cell, a fuel cell temperature detector for detecting a temperature of the fuel cell, a coolant temperature detector for detecting a temperature of the coolant in the coolant path, and a controller for controlling the amount of coolant circulated by the coolant supply device. The controller selects an operation mode of the fuel cell between a power generation mode and a power generation stop mode and calculates the difference between the detected coolant temperature and detected fuel cell temperature. While the operation mode is the power generation stop mode, the controller increases the amount of the coolant circulated as the difference between the detected coolant temperature and the detected fuel cell temperature increases.

Abstract: A fuel cell stack includes a heat exchange unit that performs heat exchange between a gas mixture containing source hydrogen and a circulating gas and cooling water used for controlling the temperature of the fuel cell stack. A system controller adjusts the temperature of the cooling water by controlling a temperature control unit on the basis of the temperature of source hydrogen flowing into a junction at which the source hydrogen and a circulating gas are mixed such that the temperature of a source/recirculated hydrogen mixture that is mixed at the junction and that is supplied to the fuel cell stack is kept within a managed temperature range.

Abstract: A fuel cell system according to this invention comprises: a pressurizing valve (2a) provided on a cooling water circulation path; a reservoir tank (5) into which the cooling water flows through a pipe (4) when the pressurizing valve (2a) is open; an air supply pipe (13) that is connected to the reservoir tank (5) to supply air for diluting a fuel gas when the fuel gas accumulates in the reservoir tank (5); and a diluted gas exhaust pipe (15) for discharging the diluted fuel gas from the reservoir tank (5).

Abstract: The present invention provides a fuel cell system having means for controlling the flow of coolant within a fuel cell system. A desirable rate of flow of coolant is created, during power generation, by determining the difference in temperature between coolant flowing into individual cell sets of the fuel cell assembly and the temperature of coolant exhausted from the cell assembly. The fuel cell system features controls adapted to evaluate the heat generation state of each fuel cell set and to regulate the temperature of cell sets by controlling the rate circulation of the coolant.

Abstract: At shutdown of a fuel cell system, a system-shutdown controller is configured to cause a current extraction device to extract current from a fuel cell in a state where a supply of a fuel gas through a fuel supply system is continued and a supply of an oxidant gas through an oxidant supply system is stopped, and the system-shutdown controller is configured to airtightly close fresh-air control valves after increasing pressure of the fuel gas in a fuel electrode to not less than atmospheric pressure and not less than pressure of the oxidant gas in an oxidant electrode.