An ejector has a variable nozzle structure and is installed in a fuel cell recirculation line to supply new hydrogen and a recirculation gas. The ejector includes: a first housing having a first hole through which hydrogen is supplied and an orifice through which the hydrogen is discharged; a second housing disposed in the first housing and having a second hole into which the hydrogen passing through the first hole flows; and a poppet penetrating a third hole defined at one side of the second housing. The poppet is configured to adjust an area of a space opened by the orifice discharging the hydrogen. The hydrogen flowing into the second housing is discharged through a space between the other side opposite to the one side of the second housing and the poppet to move to the orifice.

A hydrogen storage system may include a storage container storing liquid hydrogen, a supply line connected to the storage container and to a fuel cell system, the supply line supplying gaseous hydrogen to the fuel cell system from the storage container, a compressor mounted in the supply line and compressing the gaseous hydrogen, a bypass line connecting the supply line and the storage container and allowing the gaseous hydrogen to flow from the supply line to the storage container, a control valve mounted in the bypass line and selectively adjusting a bypass flow rate of the gaseous hydrogen, an orifice provided in the bypass line, and a controller configured to control the control valve, accurately adjusting a supply pressure of the storage container and a supply amount of the hydrogen to be supplied to the fuel cell system based on the operation conditions of the fuel cell system.

An air handling system for a fuel cell stack includes a pneumatic storage device disposed downstream from a compressor, a flow control valve system configured to operatively couple an inlet of the pneumatic storage device to an outlet of the compressor and configured to operatively couple an outlet of the pneumatic storage device to an inlet of the fuel cell stack, and a controller configured to, in response to a power demand being greater than a threshold, cause the flow control valve to open to increase a flow rate of air from the pneumatic storage device to the fuel cell stack.

The present invention provides, in a first aspect, an electrical generation system which includes an electrolyzer and a fuel cell system. The electrolyzer is coupled to a source of water and a power source. The electrolyzer is configured to generate oxygen and hydrogen utilizing water from the water source and electrical power from the power source. The fuel cell system is coupled to the electrolyzer to receive a flow of the hydrogen from the electrolyzer at an anode thereof. The fuel cell system includes a cathode having a cathode chamber coupled to a source of ambient air. The cathode chamber is coupled to the electrolyzer to selectively allow a flow of the oxygen from the electrolyzer to the cathode chamber and to selectively allow a flow of air from the source of ambient air to the cathode chamber. The fuel cell system is configured to generate electricity in a fuel cell reaction utilizing the hydrogen and the oxygen.

The invention relates to a pressure-controlled shut-off valve (1) for temporarily interrupting the air supply to a fuel cell stack in a fuel cell system, comprising a valve piston (3) which can be moved back and forth in a cylindrical housing bore (2) and which is biased in the direction of a seal seat (5) by the spring force of a spring (4), wherein a connection between an air inlet channel (6) and an air outlet channel (7) is produced or interrupted depending on the axial position of the valve piston (3). According to the invention, the valve piston (3) delimits a spring chamber (8), which receives the spring (4) and to which ambient pressure is applied, on one side and a control chamber (9), which is connected to the air inlet channel (7), on the other side within the housing bore (2). The invention additionally relates to a fuel cell system comprising a shut-off valve (1) according to the invention.

The present invention relates to a filter unit (100, 301) for filtering a fluid (105) for the operation of a fuel cell. The filter unit (100, 301) comprises at least one filter element (101) filled with a filter material (103) comprising cyclodextrin. The presented Invention also relates to a fuel cell system, to the use of cyclodextrin to filter a fluid for the operation of a fuel cell system, and to a method for operating a fuel cell system.

The invention relates to a method for detecting a leak in an energy converter system (1) containing a gas. A pressure regulator (3) is used to regulate a gas pressure in the energy converter system (1), and the pressure regulator (3) has a gas metering valve (4). The method has the following steps: a. measuring an inlet pressure (10) of the pressure regulator (3) and measuring an outlet pressure (12) of the pressure regulator (3), b. measuring an output variable (16) of the energy converter system (1) and calculating a gas requirement in the energy converter system (1) on the basis of the output variable (16) of the energy converter system (1), c. determining a first calculated flow (20) through the pressure regulator (3) on the basis of the measured inlet pressure (10) of the pressure regulator (3) and the measured outlet pressure (12) of the pressure regulator (3), d. determining a second calculated flow (22) through the pressure regulator (3) on the basis of the gas requirement, e. comparing the first calculated flow (20) with the second calculated flow (22) by generating a first comparison value (24) from the first calculated flow (20) and the second calculated flow (22), and f. determining a first threshold (26) and generating an error signal (32) if the value of the comparison value (24) is greater than the first threshold (26).

A system for providing oxygen to a fuel cell circuit includes a compressor and a fuel cell stack having a plurality of fuel cells. The system also includes a plurality of pipes and a pressure sensor designed to detect pressure at a first location. The system also includes a memory to store a model of the fuel cell circuit and an ECU. The ECU determines a control signal corresponding to desirable operation of the compressor and determines flow values of the gas through each component based on the detected pressure and the model of the fuel cell circuit. The ECU also determines pressure values of each component based on the determined flow values and the model of the fuel cell circuit. The ECU also controls operation of the compressor based on the control signal, at least one of the flow values, and at least one of the pressure values.

An exhaust moisture removal system for an electric generation system including: a sorbent wheel; an interchanger; a hydrogen evaporator including an exhaust portion; and an exhaust outflow stream passageway configured to convey an exhaust from a hydrogen fuel cell of the electric generation system through a first pass and then through a second pass, the second pass being located downstream of the first pass, wherein the first pass of the exhaust outflow stream passageway passes through the sorbent wheel, then through the interchanger, and then through the hydrogen evaporator, and wherein the second pass of the exhaust outflow stream passageway passes through the hydrogen evaporator, then through the interchanger, and then through the sorbent wheel.

A braking control unit of a fuel cell vehicle is configured to, in a period during which the fuel cell vehicle is being braked in response to a braking request, (i) when an estimated amount of stagnant water is less than a predetermined second water amount less than a first water amount, limit an upper limit electric power of a regenerated electric power resulting from regenerative operation to a predetermined first value or below, and (ii) when the estimated amount of stagnant water is greater than or equal to the second water amount, execute an upper limit changing process of setting an upper limit electric power to a second value lower by a predetermined value than the first value.