Abstract: A fuel supply system for a fuel cell is described. One embodiment of the fuel supply system includes a fuel supply vessel; a fuel spending line in fluid communication with the fuel supply vessel and the fuel cell; a piezoelectric injector in fluid communication with the fuel spending line; and a pressure sensor connected to the fuel spending line and positioned between the fuel supply vessel and the fuel cell. A method for controlling the pressure to a fuel cell is also described.

Abstract: A valve unit for a motor vehicle having a valve housing, which includes a valve inlet and a valve outlet, and having a valve body disposed in the valve housing, which includes a cross-section, increasing up to an inflection point and decreasing once past the inflection point, and which is guided from a closed position in which the valve body seals the valve inlet to a final opened position in which the valve body abuts a stop element fixed in the valve housing, releasing the valve inlet, and in which an inflow section is formed between the valve inlet and the inflection point of the valve body, and an outflow section is formed between the inflection point of the valve body and the valve outlet.

Abstract: High pressure gas vessels can have a sensitivity to temperature of the compressed gas. Over-temperature conditions in particular may cause decreased durability and/or vessel damage, including gas leakage to the environment. Articles of manufacture, methods, and systems are provided for over-temperature protection using a passive device. The passive closing device does not require electrical power and no controller, sensors, or wiring is needed. This affords cost savings in comparison to other systems. Pressure vessels using the passive closing device can protect themselves, independent of the compressed gas fueling station configuration.

Abstract: A valve unit for a motor vehicle having a valve housing, which includes a valve inlet and a valve outlet, and having a valve body disposed in the valve housing, which includes a cross-section, increasing up to an inflection point and decreasing once past the inflection point, and which is guided from a closed position in which the valve body seals the valve inlet, to a final opened position in which the valve body abuts a stop element fixed in the valve housing, releasing the valve inlet, and in which an inflow section is formed between the valve inlet and the inflection point of the valve body, and an outflow section is formed between the inflection point of the valve body and the valve outlet.

Abstract: A method and system for preventing gas pressure in a pressure vessel from dropping below a minimum allowable pressure. Pressure readings from a pressure sensor downstream of a pressure regulator are monitored by a processor as they vary within a steady fluctuation band under normal regulated pressure conditions. When the pressure regulator reaches a fully open position in low vessel pressure conditions, the processor detects a drop in the pressure reading to a value below the recent fluctuation band, and recognizes that the pressure is dropping below the regulation pressure value. The processor can use this information to shut off flow of gas from the vessel, thus preventing the vessel from dropping below its minimum allowable pressure, regardless of the actual magnitude of the pressure reading from the sensor—which can vary through a wide range due to tolerances.

Abstract: High pressure gas vessels can have a sensitivity to temperature of the compressed gas. Over-temperature conditions in particular may cause decreased durability and/or vessel damage, including gas leakage to the environment. Articles of manufacture, methods, and systems are provided for over-temperature protection using a passive device. The passive closing device does not require electrical power and no controller, sensors, or wiring is needed. This affords cost savings in comparison to other systems. Pressure vessels using the passive closing device can protect themselves, independent of the compressed gas fueling station configuration.

Abstract: A method of fueling with compressed gas is described. In one embodiment, the method includes providing a supply of compressed gas; providing a storage tank with a fueling line, and a nozzle in the fueling line, the nozzle movable between at least a flow reduction position and a full fuel flow position; initiating fueling from the supply of compressed gas with the nozzle in the flow reduction position for a predetermined time or until a minimum pressure is obtained; when the predetermined time or the minimum pressure is obtained, moving the nozzle to the full fuel flow position; and fueling the storage tank from the supply of compressed gas with the nozzle in the full fuel flow position until fueling is completed. A vehicle incorporating the nozzle is also disclosed.

Abstract: A method and system for automatically calibrating all pressure sensors in a hydrogen storage system for a fuel cell vehicle. A pressure regulator in the hydrogen storage system, which has much greater accuracy at low pressures, is used to calibrate the high-range pressure sensors used in the hydrogen storage system. This calibration can only be done when the pressure regulator is in a fully open position. In such a condition, the pressure sensors can be calibrated to the regulation pressure value of the regulator, thus greatly improving the accuracy of the readings of the high-range sensors at the low end of their range. The calibration can be performed during fuel cell operation under certain circumstances, performed during a programmed shutdown sequence, or performed in a service procedure.

Abstract: A process fluid handling device in an electrochemical cell system having a sealing system assembly between a process fluid compartment and a drive compartment of the fluid handling device. The sealing system includes a double seal configuration forming an interconnection compartment which is supplied with barrier fluid. The sealing system provides isolation of pressurized process fluids from the drive compartment.

Abstract: A fuel supply system for a fuel cell is described. One embodiment of the fuel supply system includes a fuel supply vessel; a fuel spending line in fluid communication with the fuel supply vessel and the fuel cell; a piezoelectric injector in fluid communication with the fuel spending line; and a pressure sensor connected to the fuel spending line and positioned between the fuel supply vessel and the fuel cell. A method for controlling the pressure to a fuel cell is also described.

Abstract: A method of fueling with compressed gas is described. In one embodiment, the method includes providing a supply of compressed gas; providing a storage tank with a fueling line, and a nozzle in the fueling line, the nozzle movable between at least a flow reduction position and a full fuel flow position; initiating fueling from the supply of compressed gas with the nozzle in the flow reduction position for a predetermined time or until a minimum pressure is obtained; when the predetermined time or the minimum pressure is obtained, moving the nozzle to the full fuel flow position; and fueling the storage tank from the supply of compressed gas with the nozzle in the full fuel flow position until fueling is completed. A vehicle incorporating the nozzle is also disclosed.

Abstract: A method and system for automatically calibrating all pressure sensors in a hydrogen storage system for a fuel cell vehicle. A pressure regulator in the hydrogen storage system, which has much greater accuracy at low pressures, is used to calibrate the high-range pressure sensors used in the hydrogen storage system. This calibration can only be done when the pressure regulator is in a fully open position. In such a condition, the pressure sensors can be calibrated to the regulation pressure value of the regulator, thus greatly improving the accuracy of the readings of the high-range sensors at the low end of their range. The calibration can be performed during fuel cell operation under certain circumstances, performed during a programmed shutdown sequence, or performed in a service procedure.

Abstract: A method and system for preventing gas pressure in a pressure vessel from dropping below a minimum allowable pressure. Pressure readings from a pressure sensor downstream of a pressure regulator are monitored by a processor as they vary within a steady fluctuation band under normal regulated pressure conditions. When the pressure regulator reaches a fully open position in low vessel pressure conditions, the processor detects a drop in the pressure reading to a value below the recent fluctuation band, and recognizes that the pressure is dropping below the regulation pressure value. The processor can use this information to shut off flow of gas from the vessel, thus preventing the vessel from dropping below its minimum allowable pressure, regardless of the actual magnitude of the pressure reading from the sensor—which can vary through a wide range due to tolerances.

Abstract: A process fluid handling device is provided in an electrochemical cell system having a sealing system assembly between a process fluid compartment and a drive compartment of the fluid handling device. The sealing system comprises a double seal configuration forming an interconnection compartment which is supplied with barrier fluid. The present invention provides isolation of pressurized process fluids from the drive compartment.

Abstract: A process fluid handling device is provided in an electrochemical cell system having a sealing system assembly between a process fluid compartment and a drive compartment of the fluid handling device. The sealing system comprises a double seal configuration forming an interconnection compartment which is supplied with barrier fluid. The present invention provides isolation of pressurized process fluids from the drive compartment.

Abstract: A fuel cell system having a cooling fluid flowing therethrough includes a fuel cell stack in heat transfer communication with the cooling fluid and a conduit through which the cooling fluid flows. The conduit includes a first layer of hydrogen-permeable material. Hydrogen within the cooling fluid permeates through the first layer of hydrogen-permeable material to reduce a hydrogen content of the cooling fluid.

Abstract: A coolant reservoir and associated multi-functional unit for a thermal sub-system of a fuel cell system. The coolant reservoir includes a flame arrester positioned in a gas region of the reservoir. The multi-functional unit includes a first pressure relief valve that automatically opens if the pressure within the gas region goes above a first predetermined pressure. The multi-functional unit may also include a second pressure release valve that quickly releases pressure in the coolant reservoir if the pressure within the gas region goes above a second higher predetermined pressure. The multi-functional unit also includes an air-line and a check valve for allowing ambient air to enter the gas region if the pressure within the gas region falls below ambient pressure. The multi-functional unit also includes a cooling fluid fill line having plumbing that causes the coolant reservoir to vent prior to a cooling fluid cap being removed.

Abstract: A device and method to convert residual hydrogen present in a fuel cell cooling system into water. An oxygen-bearing fluid is supplied to the cooling system from a source that also has elevated moisture levels to minimize the likelihood that the oxygen-bearing fluid will dry out or otherwise deplete the coolant in the cooling system. One or more valves are included to avoid the formation of adverse pressure gradients that could inhibit the continued supply of the oxygen-bearing fluid to the cooling system.

Abstract: The present invention relates to a process fluid handling device in an electrochemical cell system having a fluid barrier between a process fluid compartment and a drive compartment of the fluid handling device. The fluid barrier comprises an interconnection compartment, filled with barrier gas. The pressure of the interconnection compartment is maintained above the process fluid and drive compartments, by fluid communication with barrier gas stored in a storage device. The barrier gas is preferably a non-reactive and dehumidified gas. The present invention also contemplates methods of isolating the hydrogen-containing process fluid in the process fluid compartment from the drive compartment, which is preferably in fluid communication with the ambient.

Abstract: A scheme is provided for reducing the degree to which EMI from high voltage components of a fuel cell system or a fuel cell powered vehicle is induced in low voltage components of the system or vehicle. In accordance with one embodiment of the present invention, the electrical components of the system's high voltage region and the electrical components of the system's low voltage region are positioned such that, absent EMI shielding structure between the high and low voltage components, a substantial amount of EMI from the high voltage components would be induced in the low voltage components. EMI shielding structure is configured to define a conductive enclosure about the high voltage region and the low voltage region and a conductive EMI barrier between the high voltage region and the low voltage region.