A fuel cell system includes a fuel cell, a supply device configured to supply a cathode gas to the fuel cell; and a control unit configured to execute recovery processing of causing a catalyst of the fuel cell to recover from performance deterioration by lowering an output voltage of the fuel cell. The control unit is configured to, when the recovery processing that has been executed is completed, control the supply device to place the fuel cell in a power generation paused state while making a stoichiometric ratio of the cathode gas lower than a stoichiometric ratio of the cathode gas in a normal operation state that is a state before execution of the recovery processing.

Disclosed herein is an electric power and thermal management system in which, when a shaft is rotated due to an operation of a power part, generation of electric power and a circulation of a fluid are performed together so that the generation of the electric power and a circulation structure of oil are integrated, and thus a layout can be reduced, and a structure can be simplified. In addition, in a state in which the generation of the electric power and the circulation structure of the oil are integrated, a circulation amount of the oil is adjusted according to an angle of an inclined plate constituting a pumping mechanism so that an oversupply of the oil to parts through which the oil is circulated can be prevented.

An apparatus for controlling a cold start and a cold shutdown (CSD) of a fuel cell system and a method thereof are provided. A monitoring device may individually monitor at least one of an amount of accumulated power and/or an accumulated driving time of one or more fuel cell stacks. A controller may select a representative fuel cell stack among the one or more fuel cell stacks, based on the amount of accumulated power and/or the amount of accumulated driving time, performs a cold start of the representative fuel cell stack, and perform cold starts of the remaining fuel cell stacks, using power of the representative fuel cell stack after the cold start of the selected representative fuel cell stack is completed. The apparatus makes power used for a cold start and a CSD highly efficient.

A method for operating a fuel cell system comprising a fuel cell assembly of a plurality of fuel cells configured to generate electrical power from a fuel flow and an oxidant flow to the plurality of fuel cells, the fuel cell assembly arranged in combination with a coolant storage module configured to supply the fuel cell assembly with a flow of coolant, the method performed when the temperature of the coolant in the coolant storage module is below a coolant temperature threshold and comprises; a first phase performed prior to activation of a coolant pump configured to deliver coolant from the coolant storage module to the fuel cell assembly and a second phase performed after activation of the coolant pump.

A stack fuel cell array featuring paired fuel-cell systems combined to generate 540 VDC for a rotorcraft. Power from the hydrogen-based fuel cells is provided to the rotorcraft. A rated electrical load of the rotorcraft helps determine how many paired fuel-cell systems are needed during any fuel-cell systems failures. Each of the paired fuel-cell systems is coupled to an electrical load of the rotorcraft. The system detects any fuel cell failures and removes other working fuel cells as needed to balance the electrical system.

Methods and systems are provided for iron preformation in a redox flow battery. In one example, a method may include, in a first condition, discharging and then charging the redox flow battery, and in a second condition, charging the redox flow battery including preforming iron metal at a negative electrode of the redox flow battery, and thereafter entering an idle mode of the redox flow battery including adjusting one or more electrolyte conditions. In some examples, each of preforming the iron metal and adjusting the one or more electrolyte conditions may increase a battery charge capacity to greater than a threshold battery charge capacity.

A propulsion system is provided including: a gas turbine engine including a combustion section having a combustor; and a modular fuel cell assembly. The modular fuel cell assembly includes: a first fuel cell string comprising a first processing unit and a first fuel cell stack, the first fuel cell stack comprising a first fuel cell defining an outlet configured to provide output products from the first fuel cell to the combustor; and a second fuel cell string comprising a second processing unit and a second fuel cell stack, the second fuel cell stack comprising a second fuel cell defining an outlet configured to provide output products from the second fuel cell to the combustor.

An electrochemical system includes fuel cell or electrolyzer modules, and a skid supporting the modules.

A fuel cell power plant system may include a fuel supply line, two or more fuel cell system fuel supply lines, and two or more power units. The fuel supply line may be configured to receive fuel. The two or more fuel cell system fuel supply lines may be connected to the fuel supply line and may be configured to receive fuel from the fuel supply line. The two or more power units may be configured to be fueled by the two or more fuel cell system fuel supply lines, respectively.

A fuel cell system includes a cathode system device, an anode system device, an ion detector, and a controller. When the concentration of fluoride ions exceeds a predetermined concentration threshold, the controller controls at least one of the cathode system device and the anode system device to adjust a load applied to the membrane electrode assemblies.