Abstract: A fuel cell system includes a fuel cell stack including a cathode to which air is supplied, and an anode to which hydrogen is supplied. In particular, the fuel cell system further includes: an air discharge line to discharge the air discharged from the fuel cell stack into the atmosphere; a pressure adjuster provided in the air discharge line to selectively open or close the air discharge line; a first hydrogen discharge line connected to the fuel cell stack and the air discharge line at an upstream side of the pressure adjuster; a second hydrogen discharge line connected to the first hydrogen discharge line and the air discharge line at a downstream side of the pressure adjuster; and a hydrogen discharge valve part to selectively open or close at least one of the first hydrogen discharge line or the second hydrogen discharge line based on a pressure of the anode.

Abstract: The present disclosure provides an ejector nozzle and an ejector including the same. The ejector nozzle includes a first tube having a first flow path into which a fluid is introduced, and a second tube provided outside the first tube and having an inner diameter larger than an inner diameter of the first tube, the second tube defining a second flow path between the first tube and the second tube, in which the first tube further includes a communication port that penetrates the first tube to allow the first flow path to communicate with the second flow path and is openably and closable provided, and in which when the communication port is opened, a part of the fluid flowing in the first flow path is allowed to flow along the second flow path.

Abstract: The present disclosure provides an ejector nozzle and an ejector including the same. The ejector nozzle includes a first tube having a first flow path into which a fluid is introduced, and a second tube provided outside the first tube and having an inner diameter larger than an inner diameter of the first tube, the second tube defining a second flow path between the first tube and the second tube, in which the first tube further includes a communication port that penetrates the first tube to allow the first flow path to communicate with the second flow path and is openably and closably provided, and in which when the communication port is opened, a part of the fluid flowing in the first flow path is allowed to flow along the second flow path.

Abstract: A fuel cell system includes: a supply flow path configured to supply reactant gas; a first branch flow path branching off from an outlet end of the supply flow path and configured to guide the reactant gas to a first fuel cell stack; a second branch flow path branching off from the outlet end of the supply flow path and configured to communicate with the first branch flow path and guide the reactant gas to a second fuel cell stack; and an inlet area change part disposed in a boundary zone between the first branch flow path and the second branch flow path and configured to selectively change inlet areas of the first and second branch flow paths. Efficiency in discharging condensate water is increased and performance and operational efficiency are improved.

Abstract: A fuel cell system capable of improving the chemical durability of a membrane electrode assembly by compensating for the amount of an antioxidant lost within the electrolyte membrane or electrode of the fuel cell stack in such a manner that the antioxidant is provided from an antioxidant supply device, provided in a fuel processing system and/or an air processing system, to a fuel cell stack, in preparation for a case where the antioxidant within the electrolyte membrane or electrode is lost due to the dissolution or migration characteristic of the antioxidant.

Abstract: A hydrogen supply control method of a fuel cell system is provided. The method includes measuring the pressure of a front line of a supply line having relatively low humidity and the pressure of a front end of an ejector, without a pressure sensor of an anode. The amount of supplied hydrogen is then adjusted using the measured pressure and the pressure of the anode is estimated more accurately.

Abstract: A fuel cell system capable of improving the chemical durability of a membrane electrode assembly by compensating for the amount of an antioxidant lost within the electrolyte membrane or electrode of the fuel cell stack in such a manner that the antioxidant is provided from an antioxidant supply device, provided in a fuel processing system and/or an air processing system, to a fuel cell stack, in preparation for a case where the antioxidant within the electrolyte membrane or electrode is lost due to the dissolution or migration characteristic of the antioxidant.

Abstract: A solenoid valve includes a valve housing having a first space that communicates with an inlet flow path and a second space that communicates with an outlet flow path. A solenoid is provided in the valve housing to surround the first space. A flow path guide is provided in the first space and has an inflow path communicating with the first space. A plunger is rectilinearly moved in the flow path guide by the solenoid. A valve member is connected to the plunger and opens or closes the outlet flow path based on a plunger movement. A spring member provides elastic force allowing the valve member to move in a direction in which the valve member blocks the outlet flow path. A fluid guide part is formed in the plunger and guides a fluid, supplied into the inflow path via the first space, selectively to the second space.

Abstract: A method of measuring a water level in a water trap of a fuel cell system, the method including outputting a detected water level of a capacitive level sensor having a plurality of electrodes in the water trap. The method includes resetting a reference output value of each electrode and determining the water level depending on the speed at which water is introduced while detecting the water level in the water trap depending on an output value measured by the plurality of electrodes. Thereby, the influence of temperature and electrode differences is removed.

Abstract: A solenoid valve includes a valve housing having a first space that communicates with an inlet flow path and a second space that communicates with an outlet flow path. A solenoid is provided in the valve housing to surround the first space. A flow path guide is provided in the first space and has an inflow path communicating with the first space. A plunger is rectilinearly moved in the flow path guide by the solenoid. A valve member is connected to the plunger and opens or closes the outlet flow path based on a plunger movement. A spring member provides elastic force allowing the valve member to move in a direction in which the valve member blocks the outlet flow path. A fluid guide part is formed in the plunger and guides a fluid, supplied into the inflow path via the first space, selectively to the second space.

Abstract: A method is provided for controlling a hydrogen cut-off valve, which may be provided on a hydrogen supply line of a fuel cell system, in driving a fuel cell vehicle mounted with a hydrogen supply line including a high-pressure tank storing hydrogen, a hydrogen supply valve, and a hydrogen cut-off valve. The method includes: a step (a) of measuring a duty applying to the hydrogen supply valve and a step (b) of comparing the duty with a predetermined duty, in which when the duty is equal to or more than the predetermined duty, it is determined that the hydrogen supply line between the high-pressure tank and the hydrogen supply valve is abnormal.

Abstract: The present disclosure provides an ejector nozzle and an ejector including the same. The ejector nozzle includes a first tube having a first flow path into which a fluid is introduced, and a second tube provided outside the first tube and having an inner diameter larger than an inner diameter of the first tube, the second tube defining a second flow path between the first tube and the second tube, in which the first tube further includes a communication port that penetrates the first tube to allow the first flow path to communicate with the second flow path and is openably and closably provided, and in which when the communication port is opened, a part of the fluid flowing in the first flow path is allowed to flow along the second flow path.

Abstract: A method of controlling hydrogen concentration of a fuel cell includes calculating hydrogen or nitrogen concentration of gas stored in a fuel tank; estimating hydrogen or nitrogen concentration at an anode of the fuel cell based on the calculated hydrogen or nitrogen concentration of the gas; and controlling a hydrogen supply unit based on the estimated hydrogen or nitrogen concentration at the anode such that the hydrogen or nitrogen concentration at the anode follows desired hydrogen concentration or desired nitrogen concentration.

Abstract: A hydrogen supply control method of a fuel cell system is provided. The method includes measuring the pressure of a front line of a supply line having relatively low humidity and the pressure of a front end of an ejector, without a pressure sensor of an anode. The amount of supplied hydrogen is then adjusted using the measured pressure and the pressure of the anode is estimated more accurately.

Abstract: A method of measuring a water level in a water trap of a fuel cell system, the method including outputting a detected water level of a capacitive level sensor having a plurality of electrodes in the water trap. The method includes resetting a reference output value of each electrode and determining the water level depending on the speed at which water is introduced while detecting the water level in the water trap depending on an output value measured by the plurality of electrodes. Thereby, the influence of temperature and electrode differences is removed.

Abstract: A method of controlling hydrogen concentration of a fuel cell includes calculating hydrogen or nitrogen concentration of gas stored in a fuel tank; estimating hydrogen or nitrogen concentration at an anode of the fuel cell based on the calculated hydrogen or nitrogen concentration of the gas; and controlling a hydrogen supply unit based on the estimated hydrogen or nitrogen concentration at the anode such that the hydrogen or nitrogen concentration at the anode follows desired hydrogen concentration or desired nitrogen concentration.

Abstract: A device for detecting leakage of gas of a fuel cell vehicle includes a gas sensor configured to determine whether gas leaks based on a change in a temperature by a catalyst reaction and a vehicle control unit including a comparator configured to read a variation in temperature from the gas sensor, and configured to control a fuel cell vehicle. A power application state is maintained in the comparator in a power off state of the fuel cell vehicle. Power of the gas sensor is switched at regular periodic intervals. The comparator determines the variation in temperature measured by the gas sensor, and, when the variation in temperature exceeds a predetermined value, the power of the gas sensor is switched to normal power.

Abstract: A method is provided for controlling a hydrogen cut-off valve, which may be provided on a hydrogen supply line of a fuel cell system, in driving a fuel cell vehicle mounted with a hydrogen supply line including a high-pressure tank storing hydrogen, a hydrogen supply valve, and a hydrogen cut-off valve. The method includes: a step (a) of measuring a duty applying to the hydrogen supply valve and a step (b) of comparing the duty with a predetermined duty, in which when the duty is equal to or more than the predetermined duty, it is determined that the hydrogen supply line between the high-pressure tank and the hydrogen supply valve is abnormal.

Abstract: A fuel cell is provided which comprises a plurality of manifolds at a first end and a second end of the fuel cell and a separator having passages between the first and the second ends of the fuel cell. In particular, the fuel cell includes a nozzle disposed between at least one of the plurality of manifolds and the passages and having an inlet into which a material is introduced from the at least one of the plurality of manifolds and an outlet from which the introduced material is discharged to the passages.

Abstract: A device for detecting leakage of gas of a fuel cell vehicle includes a gas sensor configured to determine whether gas leaks based on a change in a temperature by a catalyst reaction and a vehicle control unit including a comparator configured to read a variation in temperature from the gas sensor, and configured to control a fuel cell vehicle. A power application state is maintained in the comparator in a power off state of the fuel cell vehicle. Power of the gas sensor is switched at regular periodic intervals. The comparator determines the variation in temperature measured by the gas sensor, and, when the variation in temperature exceeds a predetermined value, the power of the gas sensor is switched to normal power.