A concentration reducing apparatus for a fuel cell vehicle includes: a body having an inner flow path through which an exhaust gas containing a target fluid flows in a predetermined discharge direction, in which the body is made of a porous material that allows a selective discharge of the target fluid in order to selectively discharge the target fluid to an outside of the body.

The invention relates to a detection system (10a; 10b; 10c) for detecting hydrogen (11) in a cavity (12) of a fuel cell vehicle (13), comprising a fuel cell system (15) with a fuel cell housing (16) and a purging air line (17) for purging the fuel cell housing (16) and a hydrogen sensor (14) outside the fuel cell housing (16), wherein the purging air line (17) has a purging air outlet (18) for discharging purging air (19) out of the fuel cell housing (16), wherein the purging air outlet (18) is designed for applying the hydrogen sensor (14) with the purging air from the purging air line (17). The invention also relates to a fuel cell vehicle (13) comprising a detection system (10a; 10b; 10c) according to the invention.

Disclosed are a fuel cell system capable of maintaining hydrogen density of the exhaust gas discharged from the fuel cell system at a level below the tolerance limit so that any fears about fire and/or explosion can be dispelled and the safety of the system can be remarkably improved, and a humidifier therefor. The fuel cell system of the present invention comprises a fuel cell stack; and a humidifier configured to (i) humidify an air supplied from outside by means of an off-gas discharged from the fuel cell stack and (ii) supply the humidified air to the fuel cell stack, wherein the off-gas is mixed with at least a portion of the humidified air in the humidifier.

A method for increasing safety in the surroundings of an electric vehicle having a fuel cell system and batteries, wherein the vehicle is configured for charging the batteries by power from the fuel cell system and e.g. produces CO2 during this operation, even when the vehicle is turned-off and in a parked situation, wherein the method includes the steps of providing a sensor system having a gas intake and configured for warning against elevated CO2 levels in the surroundings of the vehicle, mounting the sensor system on the vehicle with the gas intake outside the vehicle's cabin, providing an alarm when the sensor system evaluates that the CO2 levels in the surroundings of the vehicle are elevated and surpass a predetermined threshold level.

A fuel cell system includes a fuel cell in which cells are stacked, a voltage sensor that detects a voltage in unit of one or more of the cells, a control unit that determines an operating point of the fuel cell and causes the fuel cell to operate. The control unit causes the fuel cell to operate at a low efficiency operating point having a lower efficiency than an efficiency of a reference operating point in a warm-up operation. In the warm-up operation, the control unit calculates a total number of the cells in which the voltage detected by the voltage sensor is equal to or less than a predetermined first reference voltage and calculates an exhaust hydrogen concentration based on the total number or the cells.

An air supply system for a fuel cell includes: a fuel cell stack in which multiple unit cells are stacked and that generates electricity through chemical reactions, an air channel to supply incoming air containing oxygen to the fuel cell stack and to transfer air discharged from the fuel cell stack to the outside of the air supply system, and a gas adsorption unit that is disposed on the air channel, positioned near an outlet of the fuel cell stack, and adsorbs oxygen contained in the air introduced into the air channel.

The present disclosure relates to a fuel cell system including: an air supply line configured to supply air to a fuel cell stack; a discharge line connected to the fuel cell stack and configured to guide exhaust gas discharged from the fuel cell stack; a discharge adapter connected to the discharge line and configured to discharge the exhaust gas to the outside; and a bypass line having one end connected to the air supply line and the other end connected to the discharge adapter, the bypass line being configured to selectively allow the air to flow from the air supply line to the discharge adapter, thereby effectively reducing a hydrogen concentration in exhaust gas discharged from the fuel cell stack.

A control unit estimates a discharged fuel gas amount, i.e., an amount of fuel gas discharged from the outlet of a cathode flow field, of a fuel exhaust gas introduced from a communication flow path to the inlet of the cathode flow field and then flowing through a cathode. The control unit calculates an oxygen-containing gas amount necessary for dilution at the time of discharge into the atmosphere, from the estimated discharged fuel gas amount, and sets a discharge amount of the air pump, based on the calculated oxygen-containing gas amount.

A fuel cell system (200) for providing electrical energy. The system (200) comprises a fuel cell stack (201), an anode subsystem (203) with a proportional valve (205) for dosing a volume of gas to be fed to the fuel cell stack (201), a purge valve (207) for discharging gas from the anode subsystem (203) into an exhaust-gas path (209) of the fuel cell system (200), and a control unit (211) for controlling the proportional valve (205) and the purge valve (207). The control unit (211) is configured to use an electrical control current that is fed to the proportional valve (205) to readjust for a purging operation to draw conclusions regarding a hydrogen concentration in a gas that is fed to the purge valve (207), wherein the control unit (211) is furthermore configured to adjust the fuel cell system (200) in a manner dependent on the determined hydrogen concentration.

A plant includes a fuel supply line for supplying high-pressure fuel gas; and at least one expander disposed in the fuel supply line and configured to extract power from the high-pressure fuel gas by expanding the high-pressure fuel gas.