Abstract: The present disclosure generally relates to systems and methods for detecting a hydrogen leak in a fuel cell system including initiating a shutdown process of a fuel cell stack in the fuel cell system by a controller, measuring a volume of hydrogen in a reservoir, pulsing a volume of hydrogen into the reservoir or pulsing hydrogen directly into the fuel cell stack if the volume of hydrogen is insufficient to sustain a voltage discharge process during the shutdown process, making the fuel cell system enter a discharge state by the controller, wherein hydrogen and oxygen in the fuel cell stack are consumed in an electrochemical reaction to discharge voltage in the fuel cell stack, measuring a rate of the voltage discharge by the controller, and detecting the hydrogen leak based on the rate of the voltage discharge or via negative pressure measurements made at the anode inlet.

Abstract: The present disclosure generally relates to systems and methods for detecting a hydrogen leak in a fuel cell system including initiating a shutdown process of a fuel cell stack in the fuel cell system by a controller, measuring a volume of hydrogen in a reservoir, pulsing a volume of hydrogen into the reservoir or pulsing hydrogen directly into the fuel cell stack if the volume of hydrogen is insufficient to sustain a voltage discharge process during the shutdown process, making the fuel cell system enter a discharge state by the controller, wherein hydrogen and oxygen in the fuel cell stack are consumed in an electrochemical reaction to discharge voltage in the fuel cell stack, measuring a rate of the voltage discharge by the controller, and detecting the hydrogen leak based on the rate of the voltage discharge or via negative pressure measurements made at the anode inlet.

Abstract: The present disclosure generally relates to systems and methods for purging water from a fuel cell stack system depending on its tilt angle and tilt location. The fuel cell stack system includes a fuel cell stack with a first corner, a second corner, a third corner and a fourth corner, a tilt sensor located on the fuel cell stack, wherein the tilt sensor is operable to detect tilt location of the fuel cell stack, and wherein the tilt location is the first, second, third or fourth corner of the fuel cell stack, a first purge valve system and a second purge valve system for removing water from an anode exhaust, and a controller.

Abstract: The present disclosure generally relates to systems and methods for operating a fuel cell system including at least two or more fuel cell systems that are connected in a parallel configuration.

Abstract: The present disclosure generally relates to systems and methods for operating a shutdown process in a fuel cell system including connecting a passive electrical load to a fuel cell stack in the fuel cell system before initiating the shutdown process, disconnecting a DC-DC converter by a system controller, initiating nitrogen blanketing after a current passing through the DC-DC converter is reduced to about zero, ensuring water content in the fuel cell stack is about zero, and sending a signal to the system controller to initiate the shutdown process.

Abstract: A method of performing a leak check of a hydrogen supply valve of a fuel cell system includes supplying hydrogen to a fuel cell stack of the system for a predetermined time period closing the supply valve and purge valves, and opening a cathode exhaust valve. The method further includes supplying oxygen to the fuel cell stack for the predetermined time period, continuously measuring a test voltage of the fuel cell stack during the predetermined time period while oxygen is being supplied to the fuel cell stack, and determining that the hydrogen supply valve is leaking in response to the test voltage exceeding a predetermined leak voltage for the predetermined time period.

Abstract: A system includes a fuel cell stack and a controller. The controller is configured to determine a current density of the fuel cell stack, determine a threshold voltage value, and compare a measured average fuel cell voltage value and the threshold voltage value. The controller is configured to set an allowed current and power draw of the fuel cell stack.

Abstract: The present disclosure generally relates to systems and methods for detecting a hydrogen leak in a fuel cell system including initiating a shutdown process of a fuel cell stack in the fuel cell system by a controller, measuring a volume of hydrogen in a reservoir, pulsing a volume of hydrogen into the reservoir or pulsing hydrogen directly into the fuel cell stack if the volume of hydrogen is insufficient to sustain a voltage discharge process during the shutdown process, making the fuel cell system enter a discharge state by the controller, wherein hydrogen and oxygen in the fuel cell stack are consumed in an electrochemical reaction to discharge voltage in the fuel cell stack, measuring a rate of the voltage discharge by the controller, and detecting the hydrogen leak based on the rate of the voltage discharge or via negative pressure measurements made at the anode inlet.

Abstract: The present disclosure relates to systems and methods for heating a fuel cell module.

Abstract: A venting system includes a housing and an air intake manifold. The housing receives a fuel cell stack, and the air intake manifold extends along the fuel cell stack. The air intake manifold directs a flow of air to the fuel cell stack, and is disposed adjacent to and in contact with the fuel cell stack.

Abstract: A fuel cell stack comprising a plurality of fuel cells, each having an anode flow field plate, a cathode flow field plate and a membrane electrode assembly disposed between the flow field plates. The anode and cathode flow field plates have primary channels and ribs separating the primary channels. At least a portion of the anode and cathode primary channels are disposed directly opposite one another with a membrane exchange assembly therebetween and with at least some of the ribs on the anode and cathode flow field plates located directly opposite one another to sandwich the membrane exchange assembly therebetween. The flow field plates can also have inlet distribution and outlet collection channels. Each of these distribution and collection channels is connected to a plurality of the primary channels, preferably located centrally, so as to improve flow distribution of the reactants.

Abstract: Aspects of some embodiments of the present invention provide flow field plates that have been designed to potentially reduce the unit cost of each flow field plate employed in an electrochemical cell stack. Thus, for some embodiments of the present invention an electrochemical cell includes a number of flow field plates each having a number of manifold apertures that all have the same area. A first one of the manifold apertures is used for a first process gas/fluid and a second one of the manifold apertures is used for a second process gas/fluid. The manifold apertures on the flow field plates align to form elongate channels that extend through the electrochemical cell as described in more detail herein.

Abstract: A fuel cell stack comprising a plurality of fuel cells, each having an anode flow field plate, a cathode flow field plate and a membrane electrode assembly disposed between the flow field plates. The anode and cathode flow field plates have primary channels and ribs separating the primary channels. At least a portion of the anode and cathode primary channels are disposed directly opposite one another with a membrane exchange assembly therebetween and with at least some of the ribs on the anode and cathode flow field plates located directly opposite one another to sandwich the membrane exchange assembly therebetween. The flow field plates can also have inlet distribution and outlet collection channels. Each of these distribution and collection channels is connected to a plurality of the primary channels, preferably located centrally, so as to improve flow distribution of the reactants.

Abstract: A fuel cell stack comprising a plurality of fuel cells, each having an anode flow field plate, a cathode flow field plate and a membrane electrode assembly disposed between the flow field plates. The anode and cathode flow field plates have primary channels and ribs separating the primary channels. At least a portion of the anode and cathode primary channels are disposed directly opposite one another with a membrane exchange assembly therebetween and with at least some of the ribs on the anode and cathode flow field plates located directly opposite one another to sandwich the membrane exchange assembly therebetween. The flow field plates can also have inlet distribution and outlet collection channels. Each of these distribution and collection channels is connected to a plurality of the primary channels, preferably located centrally, so as to improve flow distribution of the reactants.