Abstract: The present disclosure is generally directed to a design geometry of a venturi or an ejector that is optimized in systems and methods for increasing the operating range of the venturi or the ejector in a fuel cell system. The present disclosure is also generally directed to fuel cell systems and methods for sizing and/or integrating a recirculation blower with a venturi or an ejector in a fuel cell or fuel cell stack. The present disclosure is further generally directed to systems and methods of operating a fuel cell system comprising more than one venturi or ejectors during transient operations.

Abstract: The present technology relates to compounds of any one of Formula I, II, IIa, III, IV, and/or V as described herein and their tautomers and/or pharmaceutically acceptable salts, compositions, and methods of uses thereof.

Abstract: A system includes a plurality of fuel cell stacks, a balance of plant (BOP), and a first endplate and a second endplate. Each of the plurality of fuel cell stacks includes at least one fuel cell. The BOP is configured to monitor and control operation of the plurality of the fuel cell stacks. The BOP is operatively coupled to at least one of the first endplate and the second endplate to deliver, transfer, and vent fuel and oxidant to and from the plurality of fuel cell stacks.

Abstract: The present disclosure generally relates to systems and methods for assessing the health of a fuel cell stack including collecting fuel cell stack operating data by a controller including stack voltage data and cell voltage monitoring data and determining the trust in the collected data, processing stack voltage data and cell voltage monitoring data by the controller to identify bad channels and weak cells amongst fuel cells included in the fuel cell stack, tracking the state of health of the fuel cell stack by the controller, and assessing the health of the fuel cell stack by the controller.

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 system includes a fuel cell engine, a plurality of switching devices, and a controller. The fuel cell engine includes a plurality of fuel cell modules connected in series as a fuel cell string, and then a plurality of these strings connected in parallel. The switching device(s) are electrically coupled to bypass when required each module(s) and or disconnect each string(s). The decision whether a module(s) and/or string(s) are bypassed, disconnected, or left to operate is based on a sensory feedback that is input into the finite state machine and fault management process that are embedded within the fuel cell controller. The bypassing scheme at the module level is handled in a manner such that the remaining modules within a series string can provide continuous, uninterrupted flow of current to the end application.

Abstract: A humidification device includes a tubular mass exchanger fluidically coupled to receive intake air stream and transfer intake air stream to an intake air inlet of a fuel cell stack. The humidification device includes a housing configured to house the tubular mass exchanger to define a void therebetween. The housing defines at least one housing inlet opening fluidically coupled to direct an exhaust air stream output by the fuel cells tack into the void. The housing defines at least one housing outlet opening fluidically coupled to direct the exhaust air stream away from within the housing. The tubular mass exchanger is configured to extract water vapor from the exhaust air stream and transfer the extracted water vapor to the intake air stream flowing within the tubular mass exchanger to humidify the intake air stream to generate a humidified intake air stream.

Abstract: The present disclosure generally relates to systems and methods for purging water or gas from a fuel cell system. The fuel cell system may include a multi-phase valve system and/or a separate valve system.

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

Abstract: The present disclosure generally relates to systems and methods for determining, managing, and/or controlling excess hydrogen flow in a system comprising a fuel cell or fuel cell stack and ejector based on the internal state of the ejector.

Abstract: The present disclosure generally relates to systems and methods for determining, managing, and/or controlling excess hydrogen flow in a system comprising a fuel cell or fuel cell stack.

Abstract: A system includes a fuel cell engine, a plurality of switching devices, and a controller. The fuel cell engine includes a plurality of fuel cell modules connected in series as a fuel cell string, and then a plurality of these strings connected in parallel. The switching device(s) are electrically coupled to bypass when required each module(s) and or disconnect each string(s). The decision whether a module(s) and/or string(s) are bypassed, disconnected, or left to operate is based on a sensory feedback that is input into the finite state machine and fault management process that are embedded within the fuel cell controller. The bypassing scheme at the module level is handled in a manner such that the remaining modules within a series string can provide continuous, uninterrupted flow of current to the end application.

Abstract: The present disclosure relates to systems and methods for efficiently ventilating hydrogen from a fuel cell enclosure.

Abstract: This specification describes a system and method for controlling the voltage produced by a fuel cell. The system involves providing a bypass line between an air exhaust from the fuel cell and an air inlet of the fuel cell. At least one controllable device is configured to allow the flow rate through the bypass line to be altered. A controller is provided to control the controllable device. The method involves varying the rate of recirculation of air exhaust to air inlet so as to provide a desired change in fuel cell voltage.

Abstract: The present disclosure relates to systems and methods of using a proportional control valve in a fuel cell stack system. The fuel cell stack system, may comprise a fuel cell stack including an anode with an anode inlet and an anode outlet, and a cathode with a cathode inlet and a cathode outlet, and a control valve, which controls the flow of a fuel into the anode. The flow of fuel may be based on a pressure differential measured across any two of the anode inlet, the anode outlet, the cathode inlet, and the cathode outlet.

Abstract: The present disclosure generally relates to systems and methods comprising more than one venturi or ejector with a fuel cell or fuel cell stack.

Abstract: This specification describes a system and method for controlling the voltage produced by a fuel cell. The system involves providing a bypass line between an air exhaust from the fuel cell and an air inlet of the fuel cell. At least one controllable device is configured to allow the flow rate through the bypass line to be altered. A controller is provided to control the controllable device. The method involves varying the rate of recirculation of air exhaust to air inlet so as to provide a desired change in fuel cell voltage.

Abstract: A user interface may be communicatively coupled with a fluid-moving pump and may include at least two interactive regions for receiving user input to control the fluid-moving pump. The user interface may be attached to the fluid-moving pump using a mounting cover and an attachment bracket that can allow attachment or positioning of the user interface relative to the fluid-moving pump via a turn motion or other suitable methods. In other examples, the user interface can be mounted on a wall or other surface.

Abstract: 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.

Abstract: 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.