Abstract: A fuel cell system has a fuel cell stack including a plurality of fuel cells and an anode injector system, and a controller programmed. The controller, responsive to an amplitude of cyclic changes in voltage of at least some of the fuel cells exceeding a threshold, a frequency of the cyclic changes being within a predetermined range of a frequency associated with the anode injector system, and the voltage being less than a predetermined value, disables the fuel cell stack.

Abstract: A DC-DC power converter selectively electrically connected between a fuel cell stack and battery of a vehicle includes an input capacitor, an output capacitor, and an inductor electrically connected between the input and output capacitors. A flyback converter is isolated from the DC-DC power converter. One or more controllers operate the flyback converter to drive a voltage value of the input capacitor toward a voltage value of the fuel cell stack.

Abstract: A vehicle includes a fuel cell, an inlet valve, a purge valve, and a controller. The fuel cell has an anode side configured to receive hydrogen. The inlet valve is configured to open to deliver the hydrogen to the anode side. The purge valve is configured to open to purge water and nitrogen from the anode side. The controller is programmed to, operate the inlet valve to inject hydrogen into the anode side via opening the inlet valve followed by closing the inlet valve. The controller is further programmed to, in response to a concentration of the hydrogen in the anode side being less than threshold, open the purge valve to purge water and nitrogen from the anode side.

Abstract: The disclosure relates to a vehicle with a traction battery and a fuel cell system, and a controller programmed to purge the fuel cell system by flowing air through it to remove moisture from the fuel cell system. The controller is configured to initiate the purge based on a distance of the vehicle from a destination, a state of charge of the traction battery, and ambient temperature conditions at the destination. The freeze preparation process can be initiated when the vehicle is approaching its destination and can be predicted using connectivity and communication with off-board sources.

Abstract: A fuel cell system has a fuel cell stack including a plurality of fuel cells and an anode injector system, and a controller programmed. The controller, responsive to an amplitude of cyclic changes in voltage of at least some of the fuel cells exceeding a threshold, a frequency of the cyclic changes being within a predetermined range of a frequency associated with the anode injector system, and the voltage being less than a predetermined value, disables the fuel cell stack.

Abstract: Systems and methods of managing the voltage of fuel cells during no-load or low load events are disclosed. The systems may employ one or more valves such as an inlet and outlet valve for metering the fuel (e.g., hydrogen) and/or oxidant (e.g., oxygen) provided to the fuel cell. The voltage or voltage rise may be limited by starving the fuel cell of, for example, oxygen. A controller may be employed for controlling the one or more valves during a no-load or low load event such as start-up, idling, or stopping.

Abstract: A vehicle includes a fuel cell, an inlet valve, a purge valve, and a controller. The fuel cell has an anode side configured to receive hydrogen. The inlet valve is configured to open to deliver the hydrogen to the anode side. The purge valve is configured to open to purge water and nitrogen from the anode side. The controller is programmed to, operate the inlet valve to inject hydrogen into the anode side via opening the inlet valve followed by closing the inlet valve. The controller is further programmed to, in response to a concentration of the hydrogen in the anode side being less than threshold, open the purge valve to purge water and nitrogen from the anode side.

Abstract: A fuel cell system includes a stack of proton exchange membrane (PEM) fuel cells defining a body, the body including a coolant inlet and coolant outlet, a cathode inlet and cathode outlet corresponding to a cathode, an anode inlet and an anode outlet corresponding to an anode. The fuel cell system also includes a cathode humidifier fluidly connected to the cathode inlet to provide a humidified inlet stream to the cathode inlet, an oxygen sensor positioned upstream of the cathode inlet and downstream of the cathode humidifier, and configured to measure oxygen content of the humidified inlet stream, and a controller connected to the cathode humidifier and the oxygen sensor and configured to operate the cathode humidifier based on the oxygen content of the humidified inlet stream.

Abstract: A fuel cell system includes a stack of proton exchange membrane (PEM) fuel cells defining a body, the body including a coolant inlet and coolant outlet, a cathode inlet and cathode outlet corresponding to a cathode, an anode inlet and an anode outlet corresponding to an anode. The fuel cell system also includes a cathode humidifier fluidly connected to the cathode inlet to provide a humidified inlet stream to the cathode inlet, an oxygen sensor positioned upstream of the cathode inlet and downstream of the cathode humidifier, and configured to measure oxygen content of the humidified inlet stream, and a controller connected to the cathode humidifier and the oxygen sensor and configured to operate the cathode humidifier based on the oxygen content of the humidified inlet stream.

Abstract: An air-conditioning system and method of climate control for a fuel cell vehicle are provided herein. The system and method include a vacuum enclosure having an adsorber and an evaporator/condenser assembly. A conduit and valve system operates the air-conditioning system in two modes of operation to provide uninterrupted cooling to a passenger cabin, among other things. In one mode of operation, the adsorber is regenerated using waste heat from a fuel cell stack.

Abstract: A vehicle includes a fuel cell having a stack for generating power and a controller. The controller is programmed to, in response to a fuel cell temperature decreasing to less than a temperature threshold after a shutdown, initiate a primary purge of the stack and terminate the primary purge at a predetermined anode pressure.

Abstract: A fuel cell system in a vehicle includes a fuel cell stack and a cooling system for cooling the fuel cell stack. The cooling system has a radiator and at least one pump configured to supply coolant to the fuel cell stack. A controller operates the cooling system to actively cool the fuel cell stack while the vehicle is shut down in response to conditions indicating that the next time the vehicle will be started, it will be a cold start. The controller can then, subsequent to initiating the cooling, purge the fuel cell stack.

Abstract: An air-conditioning system and method of climate control for a fuel cell vehicle are provided herein. The system and method include a vacuum enclosure having an adsorber and an evaporator/condenser assembly. A conduit and valve system operates the air-conditioning system in two modes of operation to provide uninterrupted cooling to a passenger cabin, among other things. In one mode of operation, the adsorber is regenerated using waste heat from a fuel cell stack.

Abstract: A vehicle includes a fuel cell having a stack for generating power and a controller. The controller is programmed to, in response to a fuel cell temperature decreasing to less than a temperature threshold after a shutdown, initiate a primary purge of the stack and terminate the primary purge at a predetermined anode pressure.

Abstract: A fuel cell system including a fuel cell stack, a coolant loop and a thermal battery. The coolant loop is configured to flow a coolant liquid therethrough. The thermal battery includes a phase change material configured to absorb heat generated by the fuel cell stack or coolant liquid and to latently store the heat during a first mode of operation the fuel cell system.

Abstract: A fuel cell system in a vehicle includes a fuel cell stack and a cooling system for cooling the fuel cell stack. The cooling system has a radiator and at least one pump configured to supply coolant to the fuel cell stack. A controller operates the cooling system to actively cool the fuel cell stack while the vehicle is shut down in response to conditions indicating that the next time the vehicle will be started, it will be a cold start. The controller can then, subsequent to initiating the cooling, purge the fuel cell stack.