A method for diagnosing valve failure of a fuel cell system is proposed. The method comprises determining failure diagnosis target pressure from atmospheric pressure that is a real-time sensing value of an atmospheric sensor by means of a controller, controlling opening of a fuel supply valve installed in a hydrogen supply line such that stack anode-side pressure reaches the determined failure diagnosis target pressure by means of the controller, performing control for opening an integrated discharge valve installed at a water trap when the stack anode-side pressure reaches the failure diagnosis target pressure, counting a time passed after the opening, and determining whether the integrated discharge valve fails based on the time, the stack anode-side pressure, and the atmospheric pressure.

A control valve for controlling the exhausting of a purge gas from a fuel cell assembly, comprising a valve body having a valve member therein moveable between a first position and a second position, an inlet port for receiving a purge gas from the fuel cell assembly and an outlet port for providing an outlet for the purge gas, the valve member configured to, in the first position, prevent purge gas from flowing between the inlet port and the outlet port and, in the second position, allow the flow of purge gas between the inlet port and the outlet port, the valve body including a drain port adapted and arranged in the valve body to allow liquid to drain out of the valve body, the drain port configured to close when the valve member is in the second position.

A device for separating a fluid having a water and gas portion in a fuel cell system includes a fluid inlet an a fluid outlet with an outlet valve. The separating device includes a first reservoir region for collecting the water portion of the fluid. The first reservoir region includes a first outlet to feed the water portion in the direction of the fluid outlet. The separating device also includes a second reservoir region having a second outlet that feeds the water portion in the direction of the fluid outlet so that the first reservoir region 19 is connected in series in terms of flow via the second reservoir region with the fluid outlet. In an installation position of the separating device the first outlet is arranged lower than the second outlet so that deposits of the water portion completely covering the first outlet are prevented from flowing away.

A fuel cell system (100) includes a hydrogen supply valve (33) that controls a supply of the anode gas into an anode system, a purge valve (36) that discharges an off-gas from the anode system, a pressure detecting unit (34) configured to measure a pressure inside the anode system, and a purge flow rate estimating unit (4) configured to estimate a purge flow rate of the off-gas discharged from the anode system through the purge valve (36) based on a pressure decrease in a purge valve open state and a pressure decrease in a purge valve close state when an anode gas supply into the anode system stops.

A fuel cell system including a fuel cell stack having cathode and anode sides, a housing surrounding the fuel cell stack, a housing purging air inlet, an air-conveying installation disposed on the housing purging air inlet, a housing purging air outlet, an oxidation catalyst, a temperature sensor, and a control unit. The air-conveying installation continuously directs an airflow into the housing purging air inlet. The oxidation catalyst is disposed downstream of the housing purging air outlet and catalytically combusts hydrogen and oxygen. The temperature sensor is disposed on the oxidation catalyst and detects the oxidation catalyst temperature as an information item pertaining to a volumetric hydrogen flow occurring outside a fuel cell process and to be discharged. The control unit couples to the temperature sensor and to the air-conveying installation and receives the temperature detected by the temperature sensor and to therefrom determine variations of a hydrogen concentration.

The present disclosure generally relates to systems and methods for purging water or gas from a fuel cell system. The fuel cell system may include a multi-phase valve system and/or a separate valve system. The opening and closing of the valve systems for removing gas and water is controlled by a controller,

Disclosed is a method of controlling an air supply system for a fuel cell. The air supply system includes a fuel cell stack, an air channel to supply air to an inlet of the fuel cell stack, a gas adsorption unit disposed on the air channel and configured to adsorb oxygen contained in air introduced into the air channel. In particular, the method includes: determining whether a power generation operation of the fuel cell stack is resumed; when the power generation operation of the fuel cell stack is resumed, controlling a voltage source to apply a voltage to the gas adsorption unit; and supplying air to the fuel cell stack through the air channel in a state in which the voltage is applied to the gas adsorption unit.

A device and method for improving cathode catalytic heating by allowing independently for a draining of a liquid and a purging of a gas in a fuel cell at cold starts via a system including an anode drain and a cathode catalytic heating system connected by a purge tube, a sump external to the purge tube, and a pintle having a closed position, a first open position, and a second open position.

The invention relates to a fuel cell system (100) comprising a fuel cell stack (10) comprising anode chambers (11) and cathode chambers (12), an anode supply (20) comprising an anode supply path (21) for supplying an anode operating gas to the anode chambers (11), and an anode exhaust path (22) for discharging an anode exhaust gas from the anode chambers (11), and a cathode supply (30) comprising a cathode supply path (31) for supplying a cathode operating gas to the cathode chambers (12) and a cathode exhaust path (32) for discharging a cathode exhaust gas from the cathode chambers (12), and comprising a negative-pressure generation means (40) for generating a negative pressure in the cathode chambers (12). It is provided that the negative-pressure generation means (40) is designed as an ejector which is connected to a compressor (33) arranged in the cathode supply path (31) on the pressure input side, and to the cathode chambers (12) of the fuel cell stack (10) on the suction side, in a fluid-conducting manner.

A high-temperature operating fuel cell system includes a reformer that produces a reformed gas from air and a raw material, an air supplier that supplies the air to the reformer, a fuel cell that generates electricity with the reformed gas and air, a combustor in which unutilized portions of the reformed gas and the air burn, a combustion exhaust gas path of a combustion exhaust gas, a depurator including a combustion catalyst for freeing the combustion exhaust gas of toxic substances, a heater that heats the combustion catalyst, and a controller. At start-up in a case of having detected an abnormal stoppage in which a purge operation is impossible, the controller first controls the heater so that the combustion catalyst is heated to a predetermined temperature and then controls the air supplier so that the high-temperature operating fuel cell system is purged by supplying the air to the reformer.