Abstract: One aspect of the present disclosure is directed to a fuel cell power system. The system may include one or more fuel cells configured to generate electric power and a compressor configured to supply compressed air to the one or more fuel cells. The system may further include one or more sensors. The sensors may be configured to generate a signal indicative of at least one measured parameter of air flow across the one or more fuel cells. The system may also include a controller in communication with the one or more fuel cells, the compressor, and the sensors. The controller may be configured to determine a desired pressure drop based on at least one calculated parameter, determine a control command for the compressor based on the desired pressure drop, and adjust the control command based on a feedback gain parameter and a feed forward gain parameter.

Abstract: The present disclosure is directed to a method and system for dynamically controlling seal decompression. The method includes monitoring a set of parameters associated with an operation of a seal, wherein the set of parameters includes a maximum pressure subjected to the seal and an exposure time at the maximum pressure, calculating a target pressure ramp down rate based on at least one of the maximum pressure and the exposure time, and decreasing a pressure about the seal at a decompression rate that is based on the target pressure ramp down rate.

Abstract: An electrochemical cell includes a pair of bipolar plates and a membrane electrode assembly between the bipolar plates. The electrochemical cell further includes a first seal defining a high pressure zone, wherein the first seal is located between the bipolar plates and configured to contain a first fluid within the high pressure zone. Further, the electrochemical cell includes a second seal defining an intermediate pressure zone, wherein the second seal is located between the bipolar plates and configured to contain a second fluid within the intermediate pressure zone. The first seal is configured to leak the first fluid into the intermediate pressure zone when the first seal unseats.

Abstract: A multi-stack electrochemical hydrogen compressor (EHC) system is provided. The EHC system may have two or more EHC stacks, wherein each EHC stack includes at least one electrochemical cell and a power supply. The EHC system may also have a controller in communication with the power supply of each EHC stack, wherein the controller is configured to reduce total energy consumption of the EHC system by independently controlling the power supply of each EHC stack.

Abstract: The present disclosure provides a recirculation device comprising a body comprising at least one first passage configured to receive an exhaust, at least one second passage configured to receive a fuel, at least one third passage configured to receive a mixture of the exhaust and the fuel, and a longitudinal axis extending from the second passage to the third passage. The device can also comprise a nozzle comprising an inner cavity for directing fuel towards an orifice, located at the smallest cross-sectional area of the inner cavity and a piston slideably located within the body comprising a first end configured to receive the fuel and a second end configured to fuel to the nozzle cavity, whereby the piston can be actuated along the longitudinal axis of the body by the exhaust controlling the flow of fuel passing through the orifice. A mixing chamber located within the body can be configured to receive an exhaust and configured to receive fuel from the orifice.

Abstract: The present disclosure is directed to a method for tuning the performance of at least one electrochemical cell of an electrochemical cell stack. The method includes supplying power to an electrochemical cell stack. The electrochemical cell stack includes a plurality of electrochemical cells. The method further includes monitoring a parameter of at least one electrochemical cell and determining if an electrochemical cell becomes impaired. The method also includes diverting a fraction of the current flow from the impaired electrochemical cell during operation of the electrochemical cell stack.

Abstract: The present disclosure is directed to a method for tuning the performance of at least one electrochemical cell of an electrochemical cell stack. The method includes supplying power to an electrochemical cell stack. The electrochemical cell stack includes a plurality of electrochemical cells. The method further includes monitoring a parameter of at least one electrochemical cell and determining if an electrochemical cell becomes impaired. The method also includes diverting a fraction of the current flow from the impaired electrochemical cell during operation of the electrochemical cell stack.

Abstract: The present disclosure is directed to a method and system for dynamically controlling seal decompression. The method includes monitoring a set of parameters associated with an operation of a seal, wherein the set of parameters includes a maximum pressure subjected to the seal and an exposure time at the maximum pressure, calculating a target pressure ramp down rate based on at least one of the maximum pressure and the exposure time, and decreasing a pressure about the seal at a decompression rate that is based on the target pressure ramp down rate.

Abstract: The present disclosure is directed to a method and system for detecting activation of a pressure relief device connected to a storage tank containing a pressurized gas. The method includes calculating a pressure relief device release rate based on a set of inputs, wherein the set of inputs includes at least one of a storage tank volume, a pressure relief set point, an orifice size of the pressure relief device, a gas density, and a reseat point for the pressure relief device. The method further includes monitoring the pressure within the storage tank and calculating a differential pressure reading over time, comparing the differential pressure reading over time to the pressure relief device release rate, and detecting a pressure relief device activation based on the comparison result.

Abstract: The present disclosure provides a recirculation device comprising a body comprising at least one first passage configured to receive an exhaust, at least one second passage configured to receive a fuel, at least one third passage configured to receive a mixture of the exhaust and the fuel, and a longitudinal axis extending from the second passage to the third passage. The device can also comprise a nozzle comprising an inner cavity for directing fuel towards an orifice, located at the smallest cross-sectional area of the inner cavity and a piston slideably located within the body comprising a first end configured to receive the fuel and a second end configured to fuel to the nozzle cavity, whereby the piston can be actuated along the longitudinal axis of the body by the exhaust controlling the flow of fuel passing through the orifice. A mixing chamber located within the body can be configured to receive an exhaust and configured to receive fuel from the orifice.

Abstract: The present disclosure is directed to a method for tuning the performance of at least one electrochemical cell of an electrochemical cell stack. The method includes supplying power to an electrochemical cell stack. The electrochemical cell stack includes a plurality of electrochemical cells. The method further includes monitoring a parameter of at least one electrochemical cell and determining if an electrochemical cell becomes impaired. The method also includes diverting a fraction of the current flow from the impaired electrochemical cell during operation of the electrochemical cell stack.

Abstract: The present disclosure is directed to a method and system for dynamically controlling seal decompression. The method includes monitoring a set of parameters associated with an operation of a seal, wherein the set of parameters includes a maximum pressure subjected to the seal and an exposure time at the maximum pressure, calculating a target pressure ramp down rate based on at least one of the maximum pressure and the exposure time, and decreasing a pressure about the seal at a decompression rate that is based on the target pressure ramp down rate.

Abstract: A cooling system is provided for use with a fuel cell. The cooling system comprises a first heat exchanger fluidly connected to an outlet passage of the fuel cell. The first heat exchanger can be configured to condense at least a portion of a fluid passing through the outlet passage of the fuel cell into liquid water. The cooling system can also comprise a second heat exchanger fluidly connected to an outlet passage of the first heat exchanger and an inlet passage of the fuel cell. The second heat exchanger can be configured to cool a fluid passing into the inlet passage of the fuel cell. In addition, the outlet passage of the fuel cell and the inlet passage of the fuel cell can be fluidly connected to a cathode of the fuel cell, and the inlet passage of the fuel cell can be configured to supply water to the cathode.

Abstract: The present disclosure is directed towards flow structures in electrochemical cells for use in high differential pressure operations. The flow structure on the low pressure-side of the cell has a larger surface area than the flow structure on the high-pressure side of the cell at the flow structure—MEA interface. The boundary of the high pressure flow structure is entirely within the boundary of the low pressure flow structure. A seal around the high pressure flow structure is also contained within the boundary of the low pressure flow structure. In such an arrangement, high fluid pressures acting on the electrolyte membrane from the high-pressure side of the cell is fully and continuously balanced by the flow structure on the low pressure-side of the membrane. Use of the low pressure flow structure as a membrane support prevents the rupture or deformation of the membrane under high stresses.

Abstract: The present disclosure is directed towards flow structures in electrochemical cells for use in high differential pressure operations. The flow structure on the low pressure-side of the cell has a larger surface area than the flow structure on the high-pressure side of the cell at the flow structure—MEA interface. The boundary of the high pressure flow structure is entirely within the boundary of the low pressure flow structure. A seal around the high pressure flow structure is also contained within the boundary of the low pressure flow structure. In such an arrangement, high fluid pressures acting on the electrolyte membrane from the high-pressure side of the cell is fully and continuously balanced by the flow structure on the low pressure-side of the membrane. Use of the low pressure flow structure as a membrane support prevents the rupture or deformation of the membrane under high stresses.

Abstract: A cooling system is provided for use with a fuel cell. The cooling system comprises a first heat exchanger fluidly connected to an outlet passage of the fuel cell. The first heat exchanger can be configured to condense at least a portion of a fluid passing through the outlet passage of the fuel cell into liquid water. The cooling system can also comprise a second heat exchanger fluidly connected to an outlet passage of the first heat exchanger and an inlet passage of the fuel cell. The second heat exchanger can be configured to cool a fluid passing into the inlet passage of the fuel cell. In addition, the outlet passage of the fuel cell and the inlet passage of the fuel cell can be fluidly connected to a cathode of the fuel cell, and the inlet passage of the fuel cell can be configured to supply water to the cathode.

Abstract: The present disclosure is directed to steam reformers for the production of a hydrogen rich reformate, comprising a shell having a first end, a second end, and a passage extending generally between the first end and the second end of the shell, and at least one heat source disposed about the second end of the shell. The shell comprises at least one conduit member comprising at least one thermally emissive and high radiant emissivity material, at least partially disposed within the shell cavity. The shell further comprises at least one reactor module at least a portion of which is disposed within the shell cavity and about the at least one conduit member and comprises at least one reforming catalyst.

Abstract: The present disclosure is directed to steam reformers for the production of a hydrogen rich reformate, comprising a shell having a first end, a second end, and a passage extending generally between the first end and the second end of the shell, and at least one heat source disposed about the second end of the shell. The shell comprises at least one conduit member comprising at least one thermally emissive and high radiant emissivity material, at least partially disposed within the shell cavity. The shell further comprises at least one reactor module at least a portion of which is disposed within the shell cavity and about the at least one conduit member and comprises at least one reforming catalyst.

Abstract: An electrochemical cell is disclosed comprising, a first flow structure, a second flow structure, and a membrane electrode assembly disposed between the first and second flow structures. The electrochemical cell further comprises a pair of bipolar plates, wherein the first flow structure, the second flow structure, and the membrane electrode assembly are positioned between the pair of bipolar plates. The electrochemical cell also includes a spring mechanism, wherein the spring mechanism is disposed between the first flow structure and the bipolar plate adjacent to the first flow structure, and applies a pressure on the first flow structure in a direction substantially toward the membrane electrode assembly.

Abstract: An electrochemical cell includes a pair of bipolar plates and a membrane electrode assembly between the bipolar plates. The electrochemical cell further includes a first seal defining a high pressure zone, wherein the first seal is located between the bipolar plates and configured to contain a first fluid within the high pressure zone. Further, the electrochemical cell includes a second seal defining an intermediate pressure zone, wherein the second seal is located between the bipolar plates and configured to contain a second fluid within the intermediate pressure zone. The first seal is configured to leak the first fluid into the intermediate pressure zone when the first seal unseats.