Abstract: An internal resistance measurement device for stacked battery includes an AC power supply part for outputting an AC current to an measurement-object, which includes at least a stacked battery made of a plurality of stacked power generating elements, by being connected to the measurement-object, an AC adjusting part for adjusting an AC current so that a positive-electrode AC potential difference, which is a potential difference obtained by subtracting potential in a middle portion from potential in a portion connected to a load device on the positive side of the measurement-object, matches a negative-electrode AC potential difference, which is a potential difference obtained by subtracting potential in the middle portion from potential in a portion connected to the load device on the negative side of the measurement-object, and a resistance calculating part for calculating resistance of the battery based on the adjusted AC current and the AC potential difference.

Abstract: A fuel cell system can be initiated in shorter time while minimizing the deterioration of a fuel cell. The fuel cell system includes a fuel cell stack having a fuel electrode, an oxidizer electrode and an electrolyte membrane disposed there between, the fuel cell producing electricity by an electrochemical reaction of a fuel gas and an oxidizer gas, which are supplied to the fuel electrode and the oxidizer electrode, respectively; a fuel gas supplying device for supplying the fuel gas to the fuel cell stack; an oxidizer gas supplying device for supplying the oxidizer gas to the fuel cell stack; a current controlling device for extracting a current from the fuel cell stack; and a voltage sensor disposed in at least two of the fuel cell stacks.

Abstract: A fuel cell system can be initiated in shorter time while minimizing the deterioration of a fuel cell. The fuel cell system includes a fuel cell stack having a fuel electrode, an oxidizer electrode and an electrolyte membrane disposed there between, the fuel cell producing electricity by an electrochemical reaction of a fuel gas and an oxidizer gas, which are supplied to the fuel electrode and the oxidizer electrode, respectively; a fuel gas supplying device for supplying the fuel gas to the fuel cell stack; an oxidizer gas supplying device for supplying the oxidizer gas to the fuel cell stack; a current controlling device for extracting a current from the fuel cell stack; and a voltage sensor disposed in at least two of the fuel cell stacks.

Abstract: A fuel cell system and method of controlling a fuel cell system capable of preventing deterioration in performance when the system reinitiates a normal operation from an idle stop state. For a predetermined time after reinitiating the supply of fuel gas and oxidant gas from the idle stop state, discharge of off-gas occurs and the cessation of fuel gas and oxidant gas supply is prohibited.

Abstract: A fuel cell system including: a fuel cell supplied with a fuel gas to a fuel electrode thereof and air to an air electrode thereof; a fuel gas supplying device which supplies the fuel gas to the fuel electrode; an air supplying device which supplies air to the air electrode; a fuel gas pressure regulator which regulates fuel gas pressure at the fuel electrode; a purge valve which discharges exhaust fuel gas from the fuel electrode to the outside; and a controller. The controller continues power generation of the fuel cell, controlling the fuel gas pressure regulator to lower the fuel gas pressure at the fuel electrode, having the air supplying device continuing supplying air to the air electrode with the purge valve closed; and after the fuel gas pressure at the fuel electrode becomes equal to or lower than the atmospheric pressure, stops power generation of the fuel cell.

Abstract: An aspect of the present invention provides a fuel cell system that includes a fuel cell stack (1) configured to provide electric power or electric current, a cooling unit (3, 4) configured to cool the fuel cell stack (1) by flowing a coolant through a coolant passage (2) provided in the fuel cell stack (1), an inlet temperature detecting unit (5) configured to detect the temperature of the coolant at the inlet of the fuel cell stack (1), and a control unit (21) configured to control the electric power or electric current extracted from the fuel cell stack (1) in accordance with the coolant temperature detected by the inlet temperature detecting unit (5).

Abstract: A fuel cell system (S) is provided with a fuel cell (1) supplied with hydrogen gas and oxidizing gas, a gas supply line (5) supplying the hydrogen gas to the fuel cell, a gas exhaust line (31) passing exhaust hydrogen gas expelled from the fuel cell with the exhaust hydrogen gas being able to contain nitrogen, a gas recirculation line (7) recirculating the exhaust hydrogen gas to the fuel cell at an upstream thereof, a purge valve (8) adapted to discharge the exhaust hydrogen gas, containing the nitrogen, to an outside, and a controller (100) operative to close the purge valve when judgment is made that a flow rate of the exhaust hydrogen gas passing through the purge valve during an opened state of the purge valve is equal to or greater than a predetermined value.

Abstract: A fuel cell system that has a fuel cell stack with a plurality of laminated cells, each of the laminated cells includes an electrolyte membrane interposed between a fuel electrode receiving a supply of fuel gas and an oxidizing agent electrode receiving a supply of oxidizing agent gas. A fuel gas supply device supplies a fuel gas to the fuel electrode. An oxidizing agent gas supply device supplies an oxidizing agent gas to the oxidizing agent electrode. A fuel electrode side discharge system discharges a discharge gas from the fuel electrode to an external. A circulation device re-circulates the discharge gas discharged from the fuel electrode into an upstream side of the fuel electrode. A voltage limit device limits a voltage across the fuel cell stack by drawing a current from the fuel cell stack at a time of an activation of the fuel cell system.

Abstract: A fuel cell system which includes: a fuel cell (1); a supply system (Sc) for supplying fuel gas to the fuel cell (1); a recirculation system (Rc) for recirculating unused fuel gas from the fuel cell (1), in which the fuel gas therein may contain nitrogen; a purge valve (8) for purging nitrogen contained in the fuel gas in the recirculation system (Rc); and a controller (100) for adjusting a valve opening of the purge valve (8) so that a nitrogen concentration of the fuel gas in the recirculation system (Rc) is kept constant.

Abstract: A fuel cell system includes a fuel cell stack comprising an anode (fuel electrode) and a cathode (oxidizer electrode), and a system startup run is conducted at the system startup to bring the fuel cell stack into a power extractable state (idle state).

Abstract: A fuel cell system can be initiated in shorter time while minimizing the deterioration of a fuel cell. The fuel cell system includes a fuel cell stack having a fuel electrode, an oxidizer electrode and an electrolyte membrane disposed there between, the fuel cell producing electricity by an electrochemical reaction of a fuel gas and an oxidizer gas, which are supplied to the fuel electrode and the oxidizer electrode, respectively; a fuel gas supplying device for supplying the fuel gas to the fuel cell stack; an oxidizer gas supplying device for supplying the oxidizer gas to the fuel cell stack; a current controlling device for extracting a current from the fuel cell stack; and a voltage sensor disposed in at least two of the fuel cell stacks.

Abstract: A fuel cell system and method of controlling a fuel cell system capable of preventing deterioration in performance when the system reinitiates a normal operation from an idle stop state. For a predetermined time after reinitiating the supply of fuel gas and oxidant gas from the idle stop state, discharge of off-gas occurs and the cessation of fuel gas and oxidant gas supply is prohibited.

Abstract: A fuel cell system including: a fuel cell supplied with a fuel gas to a fuel electrode thereof and air to an air electrode thereof; a fuel gas supplying device which supplies the fuel gas to the fuel electrode; an air supplying device which supplies air to the air electrode; a fuel gas pressure regulator which regulates fuel gas pressure at the fuel electrode; a purge valve which discharges exhaust fuel gas from the fuel electrode to the outside; and a controller. The controller continues power generation of the fuel cell, controlling the fuel gas pressure regulator to lower the fuel gas pressure at the fuel electrode, having the air supplying device continuing supplying air to the air electrode with the purge valve closed; and after the fuel gas pressure at the fuel electrode becomes equal to or lower than the atmospheric pressure, stops power generation of the fuel cell.

Abstract: A fuel cell system (FS) is provided with a fuel cell (1) having a fuel electrode (1c) and an oxidizer electrode (1a), disposed in opposition thereto, between which an electrolyte membrane (1b) is sandwiched, a fuel gas supply source (2) supplying fuel gas to the fuel cell through a fuel gas supply passage (4), a fuel gas discharge section (8, 8?) discharging the fuel gas, discharged from the fuel cell, to an outside of a fuel cell system, and a control section (14) executing fuel gas substituting treatment such that, during startup of the fuel cell system, the fuel gas is discharged outside the fuel cell system through the fuel gas discharge section while supplying the fuel gas so as to cause a state quantity of the fuel gas, to be supplied to the fuel cell from the fuel gas supply source, to be constant for thereby allowing the fuel gas passage and the fuel electrode to be substituted with the fuel gas.

Abstract: A fuel cell system that has a fuel cell stack with a plurality of laminated cells, each of the laminated cells includes an electrolyte membrane interposed between a fuel electrode receiving a supply of fuel gas and an oxidizing agent electrode receiving a supply of oxidizing agent gas. A fuel gas supply device supplies a fuel gas to the fuel electrode. An oxidizing agent gas supply device supplies an oxidizing agent gas to the oxidizing agent electrode. A fuel electrode side discharge system discharges a discharge gas from the fuel electrode to an external. A circulation device re-circulates the discharge gas discharged from the fuel electrode into an upstream side of the fuel electrode. A voltage limit device limits a voltage across the fuel cell stack by drawing a current from the fuel cell stack at a time of an activation of the fuel cell system.

Abstract: A fuel cell stack (1) comprises a reactive gas passage (115, 1c, 116, 1a) and a water passage (117, 1b) substantially parallel thereto, and a reactive gas is humidified by water permeating from the water passage (117, 1b) through a porous member (112a, 112c). The pressure reduction amounts in the reactive gas passage (115, 1c, 116, 1a) and the water passage (117, 1b) are respectively calculated based on the power generation load of the stack (1). From the pressure reduction amounts in the water passage (117, 1b) and the reactive gas passage (115, 1c, 116, 1a), the pressure of the reactive gas supplied to the reactive gas passage (115, 1c, 116, 1a) is controlled such that the difference in pressure between the reactive gas passage (115, 1c, 116, 1a) and the water passage (117, 1b) is within a predetermined range, whereby the reactive gas is humidified in a desirable state.

Abstract: An aspect of the present invention provides a fuel cell system that includes a fuel cell stack (1) configured to provide electric power or electric current, a cooling unit (3, 4) configured to cool the fuel cell stack (1) by flowing a coolant through a coolant passage (2) provided in the fuel cell stack (1), an inlet temperature detecting unit (5) configured to detect the temperature of the coolant at the inlet of the fuel cell stack (1), and a control unit (21) configured to control the electric power or electric current extracted from the fuel cell stack (1) in accordance with the coolant temperature detected by the inlet temperature detecting unit (5).

Abstract: A control unit calculates an integration value resulting from integration of the amount of an impurity other than a fuel gas at a hydrogen electrode, which varies in accordance with a gas pressure at the hydrogen electrode and the temperature of a fuel cell stack, when a hydrogen purge valve is set in a closed state and controls the hydrogen purge valve in an open state when the integration value becomes equal to or greater than a threshold value. The control unit calculates an integration value resulting from integration of a discharge gas flow rate from the hydrogen purge valve, which varies in accordance with the gas pressure at the hydrogen electrode and the temperature of the fuel gas, when the hydrogen purge valve is set in the open state and controls the hydrogen purge valve in the closed state when the integration value becomes equal to or greater than a threshold value.

Abstract: A fuel cell system (S) is provided with a fuel cell (1) supplied with hydrogen gas and oxidizing gas, a gas supply line (5) supplying the hydrogen gas to the fuel cell, a gas exhaust line (31) passing exhaust hydrogen gas expelled from the fuel cell with the exhaust hydrogen gas being able to contain nitrogen, a gas recirculation line (7) recirculating the exhaust hydrogen gas to the fuel cell at an upstream thereof, a purge valve (8) adapted to discharge the exhaust hydrogen gas, containing the nitrogen, to an outside, and a controller (100) operative to close the purge valve when judgment is made that a flow rate of the exhaust hydrogen gas passing through the purge valve during an opened state of the purge valve is equal to or greater than a predetermined value.

Abstract: A fuel cell system which includes: a fuel cell (1); a supply system (Sc) for supplying fuel gas to the fuel cell (1); a recirculation system (Rc) for recirculating unused fuel gas from the fuel cell (1), in which the fuel gas therein may contain nitrogen; a purge valve (8) for purging nitrogen contained in the fuel gas in the recirculation system (Rc); and a controller (100) for adjusting a valve opening of the purge valve (8) so that a nitrogen concentration of the fuel gas in the recirculation system (Rc) is kept constant.