A vehicle may include a fuel cell system configured for generating electrical energy used in the vehicle using hydrogen, an engine system including an engine and configured for generating power of the vehicle using hydrogen, an exhaust system that purifies exhaust gas discharged from the engine, and a hydrogen supply system connected to the fuel cell system, the engine system and the exhaust system, and configured for supplying the hydrogen used in the fuel cell system and the engine system, and ammonia (NH3) used in the exhaust system.

A fuel cell system (1), especially for motor vehicles, is provided with at least one fuel cell (2), which has at least two electrodes (3), to which at least one electric user (4) can be connected. The electrodes (3), especially the anode (4), are protected if a temperature-measuring device (8) measures the electrode temperature of at least one of the electrodes (3) and if a control (24) sets the water fed into the fuel cell (2) by a water feed device (11), preferably before the reformate gas enters the fuel cell (2), as a function of the measured electrode temperature.

A method conditions a fuel cell stack of a fuel cell system during a usage operation of the fuel cell system. The method determines that a conditioning of the fuel cell stack is to be carried out for increasing an electrical power provided by the fuel cell stack during usage operation. In addition, the method adjusts at least one operating parameter of the fuel cell system in order to increase a current flow through the fuel cell stack for conditioning the fuel cell stack during usage operation.

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 system and method for operating a fuel-cell system, which is attached to at least one further component via a cooling and/or lubricating circuit. A water-based, oil-free coolant and lubricant is used, and a flushing procedure for the fuel cell is initiated when a contamination of the fuel cell by the water-based, oil-free coolant and lubricant is detected.

A fuel cell system includes at least one fuel cell, an oxidant conveyor, a humidifier and at least one water sink. The oxidant conveyor conveys an oxidant through a supply line to the fuel cell. The humidifier introduces water into the oxidant flow. The humidifier is arranged in and/or downstream of the oxidant conveyor and upstream of the fuel cell. The water sink is arranged between the fuel cell and the oxidant conveyor. The water sink is formed and arranged in the supply line in such a way that it prevents liquid water located in the supply line from flowing to the oxidant conveyor.

The invention relates to a fuel cell system comprising a stack of electrochemical cells forming a polymer ion-exchange membrane fuel cell (6), a fuel gas supply circuit and an oxidant gas supply circuit.

Said oxidant gas supply circuit comprises a compressor (3) intended to compress the ambient air before it enters the fuel cell (6), and an outlet exhaust (10) intended to discharge the gases leaving the fuel cell.

Said supply circuit is connected to the fuel cell at a first access point (7) and a second access point (8).

The system additionally comprises a switching element (11) that has two positions: a first position in which the outlet of the compressor (3) is connected to the first access point (7), and the second access point (8) is connected to the outlet exhaust (10), and a second position in which the outlet of the compressor (3) is connected to the second access point (8), and the first access point (7) is connected to the outlet exhaust (10).

The system is characterized in that it contains a moisture reservoir positioned in the oxidant gas supply circuit, upstream of the first access point (7).

A fuel cell apparatus may include a stack, a stack air blower configured to supply external air to the stack, a humidifier configured to extract moisture contained in exhaust air and to supply the extracted moisture to external air supplied to the stack, a first bypass channel configured to allow exhaust air to bypass the humidifier, a first three-way valve controlled to adjust the amount of exhaust air that bypasses the humidifier, and a humidity sensor configured to sense the humidity of external air. The fuel cell apparatus may also include a second bypass channel configured to allow external air to bypass the humidifier, a second three-way valve controlled to adjust the amount of external air that bypasses the humidifier, and a controller configured to control the first three-way valve and the second three-way valve depending on the sensed humidity value of the external air.

A method comprising feeding a fuel and an oxidant to individual cells in a fuel cell stack, each having two electrode layers and an electrolyte layer arranged between the electrode layers. The method further includes compressing the cell stack with a clamping device, and detecting a compression pressure upon the cell stack with at least one pressure sensor. The method also includes determining a moisture content of the two electrolyte layers based on the detected compression pressure.

This fuel cell stack activation method is a method for activating a fuel cell stack provided with a solid polymer-containing electrolyte membrane, an anode electrode, and a cathode electrode, the method comprising: a first current application step for applying a current by electrically connecting the two electrodes via an external electrical load in a state in which a potential difference is generated between the two electrodes by supplying air as a cathode-side gas to the cathode electrode while supplying hydrogen gas as an anode-side gas to the anode electrode; and a second current application step for applying a current by electrically connecting the two electrodes via an external electrical load in a state in which a potential difference is generated between the two electrodes by supplying nitrogen gas as a cathode-side gas to die cathode electrode while supplying hydrogen gas as an anode-side gas to the anode electrode.