Abstract: A method for operating a fuel cell device comprising a fuel cell stack having at least one fuel cell, involving the steps; a) drying of the fuel cell stack upon switching off the fuel cell device; b) determining the membrane residual water and the cathode residual water by means of electrochemical impedance spectroscopy when restarting the fuel cell device; c) using a cell voltage monitoring unit to identify the wettest cathode in one of the fuel cells; d) model-based determination of the water transport from the wettest cathode to the anode and thus the anode moisture in the fuel cell device; and; e) adjusting the electric current and the fuel volume flow in dependence on the anode moisture. A fuel cell device and a motor vehicle having a fuel cell device is also provided.

Abstract: A method for starting a fuel cell device having a plurality of fuel cells under frost starting conditions is provided, which comprises: establishing the presence of frost starting conditions for the fuel cell device, anode-side supplying of a hydrogen-containing reactant and cathode-side supplying of an oxygen-containing reactant in a sub-stoichiometric ratio with an oxygen deficit, maintaining the supply of the reactants in a sub-stoichiometric ratio for a given interval of time, after elapsing of the interval of time, causing the complete discharging of the fuel cells in a discharge phase, and then converting the fuel cell device to a normal mode with the supplying of the reactants according to the requirements for the given operating state and the power demand. A fuel cell device and a motor vehicle are also provided for carrying out such a method.

Abstract: A method for starting a fuel cell device having a plurality of fuel cells under frost starting conditions is provided, which comprises: establishing the presence of frost starting conditions for the fuel cell device, anode-side supplying of a hydrogen-containing reactant and cathode-side supplying of an oxygen-containing reactant in a sub-stoichiometric ratio with an oxygen deficit, maintaining the supply of the reactants in a sub-stoichiometric ratio for a given interval of time, after elapsing of the interval of time, causing the complete discharging of the fuel cells in a discharge phase, and then converting the fuel cell device to a normal mode with the supplying of the reactants according to the requirements for the given operating state and the power demand. A fuel cell device and a motor vehicle are also provided for carrying out such a method.

Abstract: A method for controlling an external electric power supply system supplying electric power from a fuel cell and a secondary battery mounted on a vehicle to an external load, the method including controlling electric power from the fuel cell and the secondary battery such that externally supplied electric power supplied to the external load is equal to or less than supply allowed electric power, and setting the supply allowed electric power to be equal to or less than a smaller one of an upper limit value of electric power which the secondary battery is charged with set in accordance with a temperature, and an electric power storage amount of the secondary battery and an upper limit value of electric power discharged from the secondary battery set in accordance with the temperature and the electric power storage amount of the secondary battery.

Abstract: A fuel cell vehicle air-conditioning apparatus includes: a cooling system that adjusts a temperature of a fuel cell; a waste heat collection unit that collects at least a part of waste heat from the fuel cell and uses the collected waste heat to heat a cabin interior of the fuel cell vehicle; and a heat creation unit that creates heat for heating the fuel cell vehicle. The fuel cell vehicle air-conditioning apparatus calculates a fuel consumption amount required for the fuel cell to generate a total power generation amount, which is a sum of a heating power generation amount and a travel power generation amount, calculates an optimum temperature, which is a temperature of the fuel cell at which the fuel consumption amount reaches a minimum, and controls the cooling system such that the temperature of the fuel cell reaches the optimum temperature.

Abstract: The vehicle control apparatus configured to control a vehicle includes a fuel cell configured to supply electric power to the vehicle; an air conditioning mechanism having a heater core; a first medium circuit; a radiator installed in the first medium circuit; a bypass circuit formed in the first medium circuit to make a bypass flow of the cooling medium bypassing the radiator; a regulation valve installed in the first medium circuit to regulate a ratio of a flow rate of the cooling medium going through the radiator to a flow rate of the cooling medium going through the bypass circuit; a second medium circuit; a cooling medium circulation pump installed in at least one of the first medium circuit and the second medium circuit; a temperature acquisition module; a warm-up controller; and a state switchover structure.

Abstract: A current measurement device includes a measurement part that is constituted by including a resistance part having a predetermined electric resistance value and a pair of current collector parts for extracting a potential difference generated by a current that flows the resistance part; a potential difference detector that is connected to the pair of current collector parts and detects a potential difference generated in the resistance part; and a current detector that detects the current that flows through the inside of a fuel cell. The measurement part is disposed to be integrated with one separator of the pair of separators and the pair of current collectors is disposed so as to overlap with the resistance part when seen from a direction orthogonal to the stacking direction of the cells.

Abstract: An exhaust state control device for a fuel cell for a mobile unit includes an exhaust gas temperature sensor (17) that measures the temperature of exhaust gas in a discharge passage that discharges the exhaust gas from the main body of the fuel cell, and an ambient temperature sensor (19A) that measures the temperature of ambient air to which exhaust gas is to be discharged. If, based on the difference between the exhaust gas temperature and the ambient temperature, it is determined that white smoke is generated, it is determined whether a condition to reduce white smoke is satisfied. When a first condition is satisfied, a process to reduce white smoke is activated. When a second condition, which requires further reduction of white smoke than under the first condition, is satisfied, a process to suppress the generation of white smoke is activated.

Abstract: A fuel cell system comprises a fuel cell stack, a circulation flow path of a cooling medium, a pump provided in the circulation flow path, a supply-side temperature sensor provided to detect a supplied cooling medium temperature, a discharge-side temperature sensor provided to detect a discharged cooling medium temperature, and a cold-start controller configured to control a circulation volume of the cooling medium by the pump at a cold start of the fuel cell stack. The cold-start controller estimates a fuel cell internal temperature and selectively sets the circulation volume of the cooling medium between a reduced volume and a normal volume, based on a magnitude relationship between the internal temperature and the discharged cooling medium temperature.

Abstract: In a fuel cell monitoring device, a gas-diffusion resistance calculation section calculates a gas-diffusion resistance Rtotal indicating a difficulty of diffusing reaction gas to a catalyst layer in a fuel cell based on a gas reaction resistance Rct calculated by a resistance calculation section. A second diffusion resistance calculation section calculates a second diffusion resistance Rdry varying depending on a dried-up in the fuel cell based on a proton transfer resistance Rmem calculated by the resistance calculation section. A first diffusion resistance calculation section calculates a first diffusion resistance Rwet varying depending on a flooding in the fuel cell by subtracting the second diffusion resistance Rdry from the gas-diffusion resistance Rtotal. A water content calculation section calculates a water content of the fuel cell based on the first diffusion resistance. A recovery control section adjusts the water content in the fuel cell based on the calculated water content.

Abstract: The invention is provided to reliably restore generated voltage that has declined due to clogging of water in a fuel cell stack. A method of operating a fuel cell system having a fuel cell stack that generates electricity through an electrochemical reaction between a fuel gas including hydrogen gas and an oxidation gas, wherein when a generated voltage of the fuel cell stack declines, the water-in-cell content of the fuel cell stack is adjusted so that a variation in cell pressure loss in the fuel cell stack decreases based on a characteristic curve of the water-in-cell content of the fuel cell stack and the cell pressure loss of the fuel cell stack.

Abstract: A method for controlling an external electric power supply system supplying electric power from a fuel cell and a secondary battery mounted on a vehicle to an external load, the method including controlling electric power from the fuel cell and the secondary battery such that externally supplied electric power supplied to the external load is equal to or less than supply allowed electric power, and setting the supply allowed electric power to be equal to or less than a smaller one of an upper limit value of electric power which the secondary battery is charged with set in accordance with a temperature, and an electric power storage amount of the secondary battery and an upper limit value of electric power discharged from the secondary battery set in accordance with the temperature and the electric power storage amount of the secondary battery.

Abstract: A fuel cell system comprises a fuel cell stack, a circulation flow path of a cooling medium, a pump provided in the circulation flow path, a supply-side temperature sensor provided to detect a supplied cooling medium temperature, a discharge-side temperature sensor provided to detect a discharged cooling medium temperature, and a cold-start controller configured to control a circulation volume of the cooling medium by the pump at a cold start of the fuel cell stack. The cold-start controller estimates a fuel cell internal temperature and selectively sets the circulation volume of the cooling medium between a reduced volume and a normal volume, based on a magnitude relationship between the internal temperature and the discharged cooling medium temperature.

Abstract: A fuel cell system includes: a fuel cell having laminated cells; a measuring unit that measures an impedance of the cell and a purging unit that performs purging to discharge residual water from a gas passage. The cell includes a wet region and a dry region which are set depending on a distribution of water in the cell when the purging is executed so as to set a total amount of water in the fuel cell to be a necessary amount of water to start up the fuel cell; the measuring unit measures the impedance at a local portion located at a boundary portion between the wet region and the dry region in the cell; and the purging unit terminates the purging when the impedance measured by the measuring means is larger than a predetermined reference threshold value.

Abstract: In order to cause a plurality of cells in a fuel cell to be recovered to a desired humidity state, it is configured to determine that the cells present a mixture of dry and overly humid states in the case where a predetermined condition is satisfied, and in the case where it is determined that the cells present the mixture, humidifying control is carried out to cause all the cells to attain the overly humid state, and thereafter, drying control is carried out to dry all the cells, to thereby cause the plurality of cells to be recovered to a predetermined humidity state.

Abstract: A fuel cell system includes: a fuel cell; a secondary cell that receives and stores surplus power by which output of the fuel cell is greater than power demanded of the system if the output is so, and that compensates for shortfall by which the output of the fuel cell is less than the power demanded of the system if the output is so; a voltage measurement portion that measures voltage of the fuel cell; a current measurement portion that measures current of the fuel cell; and a control portion that performs a control such that the voltage of the fuel cell does not exceed or equal a pre-set high-potential avoidance voltage. If a current-voltage characteristic of the fuel cell declines by at least a pre-determined amount from an early-period level, the control portion re-sets the high-potential avoidance voltage to a value that is smaller than an early-period set value.

Abstract: The present invention relates to a fuel cell system that is capable of running a detailed diagnostic check on the internal dryness of a fuel cell. The fuel cell system measures the distribution of electrical current density on a power generation plane of the fuel cell, and diagnoses the internal dryness of the fuel cell in accordance with changes in the peak position of electrical current density on the power generation plane. If the fuel cell is configured to let a reactant gas (hydrogen) on the anode side and a reactant gas (air) on the cathode side flow in opposing directions with the power generation plane positioned in between, the fuel cell system judges whether the peak position of electrical current density is displaced toward the outlet of an anode or the outlet of a cathode. In accordance with the result of judgment, the fuel cell system can determine whether dry-up has occurred on the anode side or cathode side.

Abstract: An odorant addition device for adding odorant to fuel gas in a gas system that consumes the fuel gas, the device including: an addition unit for adding the odorant to fuel gas to be consumed by the gas system; an environmental condition detection unit for detecting in the gas system an environmental condition regarding diffusion of odorant in fuel gas; and an addition adjustment unit for adjusting mode of odorant addition by the addition unit based on the environmental condition detected by the environmental condition detection unit. In this way, it is possible to detect leakage of fuel gas more reliably and improve safety dramatically, in a gas system that consumes the fuel gas as fuel.

Abstract: A current measurement device includes a measurement part that is constituted by including a resistance part having a predetermined electric resistance value and a pair of current collector parts for extracting a potential difference generated by a current that flows the resistance part; a potential difference detector that is connected to the pair of current collector parts and detects a potential difference generated in the resistance part; and a current detector that detects the current that flows through the inside of a fuel cell. The measurement part is disposed to be integrated with one separator of the pair of separators and the pair of current collectors is disposed so as to overlap with the resistance part when seen from a direction orthogonal to the stacking direction of the cells.

Abstract: A fuel cell is used for generating driving energy for a vehicle. The reserve-tank inlet valve is located between a suction side of the coolant pump and a position in the coolant circuit at which a pressure of the coolant controlled by the reserve-tank inlet valve is an intermediate value between a discharge pressure of the coolant pump and a suction pressure of the coolant pump during an operation of the coolant pump. Even if the fuel cell is stopped generating electric power, the coolant pump is made continue operating even when the vehicle is traveling in a case that a coolant temperature exceeds a predetermined temperature. The coolant pump is made stop rotating after the coolant temperature becomes lower than or equal to the predetermined temperature.