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 system and method for cooling and humidifying a cathode subsystem of a fuel cell for an automobile. The system includes a compressor, an air input line including an intercooler configured to cool air output by the compressor, a fluid output line including a fluid injection system, a cathode stack configured to receive air via the air input line and output a fluid to the fluid output line, and an electronic processor. The electronic processor is configured to control the fluid injection system such that the fluid output from the cathode stack is injected into the air input line.

A gas liquid separator of a fuel cell system includes a first channel forming section forming a first channel for allowing an oxygen-containing exhaust gas to flow in a horizontal direction, and a second channel forming section forming a second channel connected to the first channel. The first channel forming section is provided with an inlet for guiding the oxygen-containing exhaust gas into the first channel. The second channel forming section is provided with an outlet for discharging the oxygen-containing exhaust gas flowing through the second channel. The second channel includes a bent channel for guiding upward the oxygen-containing exhaust gas guided from the first channel.

A fuel cell system includes a fuel cell unit having an air inlet, a fuel inlet and an electrical energy outlet and a fuel cell exhaust outlet and a turbo-compressor unit to convert air from an air supply to compressed inlet air for the fuel cell unit. The turbo-compressor unit comprising a turbine and a compressor connected to a common rotatable shaft. The system also includes means for obtaining conditioned air exhausted from an enclosed space and directing the conditioned exhaust air to the turbine of turbo-compressor unit such that the conditioned exhaust air is expanded by the turbine causing rotation of the shaft and corresponding rotation of the compressor, means for providing air from the air supply to the compressor to be compressed and output from the compressor unit and provided as compressed inlet air to the air inlet of the fuel cell unit.

A fuel cell system includes a fuel cell stack, a fuel inlet conduit configured to provide a fuel to a fuel inlet of the fuel cell stack, an electrochemical pump separator containing an electrolyte, a cathode, and a carbon monoxide tolerant anode, a fuel exhaust conduit that operatively connects a fuel exhaust outlet of the fuel cell stack to an anode inlet of the electrochemical pump separator, and a product conduit which operatively connects a cathode outlet of the electrochemical pump separator to the fuel inlet conduit.

A humidifier for humidifying a dry cathode supply air via a humid cathode exhaust air in a fuel cell system, may include a housing, a membrane stack, and/or a sealing arrangement. The membrane stack may include a plurality of membranes, two first side surfaces, two second side surfaces, and/or two third side surfaces. The plurality of membranes may be stacked on one another transversely to a longitudinal direction of the membrane stack. The first side surfaces may be arranged opposite one another. The second side surfaces may be arranged opposite one another. The third side surfaces may be arranged opposite one another. The sealing arrangement may include two sealing frames, each of the sealing frames is assigned to one of the respective first side surfaces. Each of the sealing frames may have a frame-shaped contact area and a retaining edge protruding from the contact area.

A membrane humidifier has a housing and a membrane stack. The membrane stack includes two first stack sides aligned parallel to the assembly direction. The membrane humidifier has a sealing device with two first sealing frames, each with an inner sealing surface and an outer sealing surface. The housing has two first housing sealing surfaces. The first sealing frames are in sealing contact with the inner sealing surfaces on the first stack sides. The first sealing frames are in contact with the outer sealing surfaces on the first housing sealing surfaces. The outer sealing surfaces of the first sealing frames and the first housing sealing surfaces of the housing are each aligned at a mounting angle to the first stack sides and to the mounting direction that is not zero. In addition, an arrangement is provided which includes the membrane humidifier and the sealing device for the membrane humidifier.

A combined cooling and humidifying system for a fuel cell system includes a first line strand, second line strand, gas separator, and water feed device. The first line strand has a supply line for feeding water to a heat exchanger of the fuel cell system and a return line for receiving a water-steam mixture from the fuel cell system. The gas separator is in the return line to at least partially separate the steam from the water-steam mixture and provide it at a steam connection. The second line strand has a fluid inlet for feeding a gaseous fluid to the fuel cell system. The steam connection is coupled to the second line strand downstream of the fluid inlet to admix steam with the fluid. The water feed device is coupled to the supply line to compensate for a separating mass flow of steam in the first line strand.

A method for humidifying a reactant in a fuel cell system is provided having a fuel cell stack, which is fluidically connected to a humidifier, wherein the humidifier comprises a membrane, on whose surface channels are formed. At least one of the channels is associated with a storage element for temporary storing of liquid water, the method involving the following steps: extracting the liquid water from the fuel cell stack and feeding the liquid water to the humidifier, admitting at least part of the liquid water into the storage element and temporarily storing the part therein, at least partially emptying the storage element by evaporating of the liquid water and humidifying of the reactant being supplied to the fuel cell stack by means of the evaporated liquid water, wherein the liquid water is extracted from the fuel cell stack both at the anode side and at the cathode side. A fuel cell system for carrying out the method is also provided.

A fuel cell system includes a fuel cell, first and second supply devices, a gas-liquid separator, a discharge valve, first and second ejectors for discharging fuel gas and off gas to the fuel cell, a measuring device for gas pressure, and a control device. The first ejector has a discharge amount smaller than the second ejector. The first ejector has a circulation amount larger than the second ejector. The control device executes the supply during a first time from the first supply device at each first cycle such that the pressure becomes a first target value, and when the first ejector is in an abnormal state, stops the first supply device, executes the supply during a shorter second time from the second supply device at each shorter second cycle such that the pressure becomes a higher second target value, and opens and closes the discharge valve at each first cycle.