A fuel cell and a method for regenerating this fuel cell, including a supply of the fuel cell by the main supply conduit by a fluid having a nominal flow rate and a nominal molar fraction of combustion agent, during a regeneration phase of a given group, a switching of the inlet, outlet and recirculation switches of the fluid circuit so as to supply the given group from the recirculation line of the given group and from a fluid discharge line of at least one other group, an application of a regeneration voltage Ve to the cells of the given group, Ve being less than or equal to 0.3V.

A fuel cell recovery control system and method are provided to supply hydrogen to the cathode of a fuel cell stack to remove an oxide film formed on a platinum surface of the cathode. The performance of the fuel cell stack is recovered in accordance with the oxide film removal. In addition, electric power generated during the performance recovery of the fuel cell stack is consumed in an inverter and, as such, overcharge of a battery is prevented.

The present disclosure generally relates to systems and methods for fuel cell regeneration after degradation.

A fuel cell module is configured or operated, or both, such that after a shut down procedure a fuel cell stack is discharged and has its cathode electrodes at least partially blanketed with nitrogen during at least some periods of time. If the fuel cell module is restarted in this condition, electrochemical reactions are limited and do not quickly re-charge the fuel cell stack. To decrease start up time, air is moved into the cathode electrodes before the stack is re-charged. The air may be provided by a pump, fan or blower driven by a battery or by the flow or pressure of stored hydrogen. For example, an additional fan or an operating blower may be driven by a battery until the fuel cell stack is able to supply sufficient current to drive the operating blower for normal operation.

A method for starting a fuel cell in a fuel cell system, at temperatures below the freezing point of water, includes, in a first step, that the hydrogen concentration in the anode is increased; after which, in a second step, an anode pressure is increased for a fixed period of time, and while air is supplied to the cathode, the maximum possible current is drawn from the fuel cell, and after which, in a third step, the fuel cell is switched in a load-free manner and the anode pressure is reduced. After the third step, the second step and the third step are repeated successively until a sufficient performance of the fuel cell for its normal operation is reached.

A method of operating a fuel cell assembly comprising a plurality of fuel cells connected together for collectively providing power to a load, each fuel cell including an anode and a cathode, the method comprising selectively providing an electrical connection between the anode and the cathode of at least one of the fuel cells of the assembly for lowering the voltage across the fuel cell independent of the load.

A system and method for recovering an output of a fuel cell is provided. The system and method for recovering an output of a fuel cell includes: an output recovering device connected to a fuel cell stack through at least one coolant heater line; and a vehicle controller configured to communicate with the output recovering device and control supply of a coolant, air, and hydrogen to the fuel cell stack. The output recovering device also includes a current supplier configured to supply a current to the fuel cell stack and a controller configured to communicate with the vehicle controller and control the current supplied from the current supplier.

Methods and circuits for a device for interrupting concentration-related polarisation phenomenon and for self-cleaning of electromembrane processes by application of asymmetric inverse-polarity pulses with high intensity and variable frequency are described. The device, a bipolar switch, is based on the use of solid-state electronics to carry out polarity inversion in a range of frequencies, intensities and pulse widths to prevent or reduce formation of precipitates on the surfaces of the membranes. The inversion protocol, with a frequency that varies as a function of the appearance of dirt on the membranes, as measured by the decrease in voltage or electrical resistance of the membrane cell during electromembrane processes, is also provided. This device and configuration provides application of modulated and stable high-intensity pulses using a second power source. Electromembrane processes can be updated by replacing electrodes, suitable for polarity inversion, and adding a second power source and the bipolar switch described.

A fuel cell system according to the present invention comprises: a fuel cell including a membrane-electrode assembly in which electrodes, each having a catalyst layer, are arranged on both surfaces of a polymer electrolyte membrane; and a control apparatus that performs performance recovery processing for the catalyst layer by decreasing an output voltage of the fuel cell to a predetermined voltage, wherein the control apparatus predicts a timing of an output increase request being made to the fuel cell and determines the necessity and content of the performance recovery processing based on a result of the prediction.

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.