The fuel cell system of the present disclosure includes: a fuel cell that includes a membrane electrode assembly including a proton conducting ceramic electrolyte membrane, a cathode disposed on a first surface of the electrolyte membrane, and an anode disposed on a second surface of the electrolyte membrane, the fuel cell generating electric power through an electrochemical reaction using a fuel gas and an oxidant gas; a power source that applies a voltage to the fuel cell; and a controller. In a shutdown process, the controller controls the power source to apply the voltage to the fuel cell such that a terminal voltage of the fuel cell is equal to or higher than an open circuit voltage of the fuel cell.

The invention relates to a fuel cell system (100, 1) comprising: at least one fuel cell (200) which has a cathode (230) with a cathode chamber and has an anode chamber of an anode (210), which anode chamber is separated from the cathode chamber by a membrane, wherein the cathode chamber is connected to a cathode gas source via at least one first fluid connection (240) and the anode chamber is connected to an anode gas source via at least one second fluid connection; and comprising a first electrical connection (3) to a DC/DC converter (450) that electrically connects the anode (210) and the cathode (230) to an energy system (400), wherein in a shut-down phase of the fuel cell system (100, 1), residual energy present in the fuel cell (200) can be discharged. According to the invention, the anode (210) is connected to the energy system (400) and/or the cathode (230) via at least one second electrical connection (2), wherein the second electrical connection (2) is a bypass connection to the DC/DC converter (450) and/or the second electrical connection (2) is a bypass connection parallel to the fuel cell (200), wherein at least the residual energy can be discharged via the second electrical connection (2), and the second electrical connection (2) comprises a resistor (6).

In various aspects, systems and methods are provided for operating a molten carbonate fuel cell at increased fuel utilization and/or increased CO.sub.2 utilization. This can be accomplished in part by performing an effective amount of an endothermic reaction within the fuel cell stack in an integrated manner. This can allow for a desired temperature differential to be maintained within the fuel cell.

A fuel cell system in a vehicle has a cathode and an anode. A compressor has an inlet and an outlet, the outlet being configured to outlet a compressed air from the compressor. A bypass line is configured to return the compressed air from the outlet to the inlet such that the air returns to the compressor in a loop. A valve is located downstream of the compressor and is operable in a plurality of modes. In a first mode, the valve is configured to block the air from the cathode and return the air via the bypass line. In a second mode, the valve is configured to direct at least some of the air to the cathode. The valve can also be configured to operate in a third mode in which the air is sent to the cathode without going through the bypass line.

A fuel cell system includes: a fuel cell; a target operating point determination unit that determines a warm-up target operating point based on a required electric power amount during warm-up and a required heat generation amount during warm-up; an operation control unit; and a failure state identification unit that identifies whether an electric power consumption device that operates by consuming generated electric power generated by the fuel cell has failed. When a failure of the electric power consumption device is identified, the target operating point determination unit determines an operating point that satisfies a required electric power amount during a failure that is set to be smaller than the required electric power amount during the warm-up and a required heat generation amount during the failure that is set to be smaller than the required heat generation amount during the warm-up as a target operating point during the failure.

A process for starting a PEM fuel cell module includes blowing air through the cathode side of the module using external power. An amount hydrogen is released into the anode side of the module under a pressure greater than the pressure of the air on the cathode side, while the anode is otherwise closed. Cell voltages in the module are monitored for the appearance of a charged state sufficient to start the module. When the charged state is observed, the module is converted to a running state.

A fuel-cell system for powering an electrical load, the system having first and second fuel cells, each having a positive node and a negative node. The positive node of the second fuel cell is electrically coupled to the negative node of the first fuel cell, and the positive node of the first fuel cell and the negative node of the second fuel cell are electrically coupled to the electrical load. Each fuel cell is electrically coupled to the electrical load without a power converter.

Anion exchange membrane electrode assemblies, fuel cells and electrochemical cells comprising such assemblies, which comprise an anion exchange membrane sandwiched between an anode compartment and a cathode compartment, and which are operable at a temperature of at least 100° C., are provided. Systems, devices, articles and methods that utilize such assemblies at an operating temperature of at least 100° C. are also provided.

A power generation system includes a power source that is configured to communicate with at least one of a downstream load or a downstream device by changing a voltage on a power bus between the power source and the at least one of the downstream load or the downstream device, while power source provides power on the power bus to the at least one of the downstream load or the downstream device.

An apparatus for converting power of a fuel cell for power generation to remove an open voltage of the fuel cell when a failure occurs during power generation of the fuel cell and a method thereof are provided. A power converter converts and supplies power generated by the fuel cell to a system or load. A controller detects a failure occurring in the fuel cell, the power converter, or the system or load, while the fuel cell is driven, and reduces an open circuit voltage (OCV) of the fuel cell by a dummy resistor connected with an output terminal of the fuel cell, when the failure occurs in the fuel cell, the power converter, or the system or load. The apparatus removes an OCV of a fuel cell stack to prevent performance and life of the fuel cell from being reduced.