Abstract: A safety system for aircraft passenger seats is described. A pallet that can be removably coupled to seats can also be removably coupled to the aircraft floor and one or more brackets, tension fittings, or machined straps that can be coupled to structural beams or components in an aircraft. A keel tension fitting can be attached to a keel beam and then be coupled to the pallet and thereby the seats. By attaching to the keel beam the safety system allows the seating arrangement (pallet and seats) to withstand greater stresses and forces, resulting in increased safety.

Abstract: A safety system for aircraft passenger seats is described. A pallet that can be removably coupled to seats can also be removably coupled to the aircraft floor and one or more brackets, tension fittings, or machined straps that can be coupled to structural beams or components in an aircraft. A keel tension fitting can be attached to a keel beam and then be coupled to the pallet and thereby the seats. By attaching to the keel beam the safety system allows the seating arrangement (pallet and seats) to withstand greater stresses and forces, resulting in increased safety.

Abstract: A safety system for aircraft passenger seats is described. A pallet that can be removably coupled to seats can also be removably coupled to the aircraft floor and one or more brackets, tension fittings, or machined straps that can be coupled to structural beams or components in an aircraft. A keel tension fitting can be attached to a keel beam and then be coupled to the pallet and thereby the seats. By attaching to the keel beam the safety system allows the seating arrangement (pallet and seats) to withstand greater stresses and forces, resulting in increased safety.

Abstract: Power plant systems and processes are described that enable recovery of at least a portion of the fuel storage energy associated with a storage system for supplying fuel to the power plant systems. A first embodiment of an energy-recovery power plant system includes at least one fuel storage container and at least one expander that can receive fuel from the fuel storage container at a first pressure and provide the fuel to the power plant at a second pressure that is lower than the first pressure. A second embodiment of an energy-recovery power plant system includes a first conduit fluidly coupling the fuel storage container and the power plant for delivering fuel from the fuel storage container to the power plant and at least one regenerative thermodynamic cycle engine thermally coupled to the first conduit such that heat may be exchanged between the fuel and a working fluid for the regenerative thermodynamic cycle engine.

Abstract: An electric power generation system has elements that improve the cold start capability and freeze tolerance of a constituent fuel cell stack cooperate to reduce the amount of water remaining within the passages of the stack. The system includes a purge system that is connectable to the oxidant supply, fuel supply and/or coolant passages upstream of the stack. When the stack is shut down, the stack is disconnected from an external circuit, and purge fluid is transmitted by the purge system through the stack before the stack falls below the freezing point of water. In systems where fuel and/or oxidant streams are humidified prior to entry into the stack, a humidifier bypass system may be provided in place of the purge system. The humidifier bypass system transmits reactant fluid to the stack in fluid isolation from the humidifier, so that the inlet reactant streams are unhumidified.

Abstract: Liquid cooled systems having coolant circulation loops must often operate in below freezing conditions. For instance, in various applications certain fuel cell systems must be able to tolerate repeated shutdown and storage in below freezing conditions. Conventional glycol-based coolants typically used for internal combustion engines are generally unsuitable for use in the associated fuel cell cooling subsystems due to the presence of additives and/or inhibitors which are normally included to deal with problems relating to decomposition of the glycol. With additives or inhibitors present, the coolant conductivity can be sufficiently high as to result in electrical shorting or corrosion problems. However, provided the purity of the coolant is maintained, a pure glycol and water coolant mixture may be used as a fuel cell system coolant to obtain suitable antifreeze protection. Adequate purity can be maintained by including an ion exchange resin unit in the cooling subsystem.

Abstract: Liquid cooled systems having coolant circulation loops must often operate in below freezing conditions. For instance, in various applications certain fuel cell systems must be able to tolerate repeated shutdown and storage in below freezing conditions. Conventional glycol-based coolants typically used for internal combustion engines are generally unsuitable for use in the associated fuel cell cooling subsystems due to the presence of additives and/or inhibitors which are normally included to deal with problems relating to decomposition of the glycol. With additives or inhibitors present, the coolant conductivity can be sufficiently high as to result in electrical shorting or corrosion problems. However, provided the purity of the coolant is maintained, a pure glycol and water coolant mixture may be used as a fuel cell system coolant to obtain suitable antifreeze protection. Adequate purity can be maintained by including an ion exchange resin unit in the cooling subsystem.

Abstract: Apparatus and methods of ceasing operation of an electric power generating system improve the cold starting capability of the system. The system comprises a fuel cell stack connectable to an external circuit for supplying power to the external circuit. The stack comprises at least one solid polymer fuel cell, and the system further comprises a fuel passage for directing a fuel stream through the stack and an oxidant passage for directing an oxidant stream through the stack, a sensor assembly connected to the stack for monitoring a parameter indicative of stack performance, a controller for controlling at least one stack operating parameter, and a control system communicative with the sensor assembly and stack operating parameter controller.

Abstract: Power plant systems and processes are described that enable recovery of at least a portion of the fuel storage energy associated with a storage system for supplying fuel to the power plant systems. A first embodiment of an energy-recovery power plant system includes at least one fuel storage container and at least one expander that can receive fuel from the fuel storage container at a first pressure and provide the fuel to the power plant at a second pressure that is lower than the first pressure. A second embodiment of an energy-recovery power plant system includes a first conduit fluidly coupling the fuel storage container and the power plant for delivering fuel from the fuel storage container to the power plant and at least one regenerative thermodynamic cycle engine thermally coupled to the first conduit such that heat may be exchanged between the fuel and a working fluid for the regenerative thermodynamic cycle engine.

Abstract: Apparatus and methods of ceasing operation of an electric power generating system improve the cold starting capability of the system. The system comprises a fuel cell stack connectable to an external circuit for supplying power to the external circuit. The stack comprises at least one solid polymer fuel cell, and the system further comprises a fuel passage for directing a fuel stream through the stack and an oxidant passage for directing an oxidant stream through the stack, a sensor assembly connected to the stack for monitoring a parameter indicative of stack performance, a controller for controlling at least one stack operating parameter, and a control system communicative with the sensor assembly and stack operating parameter controller.

Abstract: A method for operating a cooling subsystem of an electrochemical fuel cell system during startup is disclosed. The method comprises directing a startup coolant through an electrochemical fuel cell stack of the fuel cell system, and directing a standard coolant through the fuel cell stack when the temperature of either the fuel cell stack or the startup coolant reaches a first predetermined temperature, wherein the heat capacity of the startup coolant is different from than the heat capacity of the standard coolant. Cooling subsystems are also disclosed.

Abstract: An electric power generation system has elements that improve the cold start capability and freeze tolerance of a constituent fuel cell stack cooperate to reduce the amount of water remaining within the passages of the stack. The system includes a purge system that is connectable to the oxidant supply, fuel supply and/or coolant passages upstream of the stack. When the stack is shut down, the stack is disconnected from an external circuit, and purge fluid is transmitted by the purge system through the stack before the stack falls below the freezing point of water. In systems where fuel and/or oxidant streams are humidified prior to entry into the stack, a humidifier bypass system may be provided in place of the purge system. The humidifier bypass system transmits reactant fluid to the stack in fluid isolation from the humidifier, so that the inlet reactant streams are unhumidified.

Abstract: The activity of catalysts used in promoting the oxidation of certain oxidizable species in fluids can be enhanced via electrochemical methods, e.g., NEMCA. In particular, the activity of catalysts used in the selective oxidation of carbon monoxide can be enhanced. A purification system that exploits this effect is useful in purifying reformate supplied as fuel to a solid polymer electrolyte fuel cell stack. The purification system comprises an electrolytic cell with fluid diffusion electrodes. The activity of catalyst incorporated in the cell anode is enhanced.

Abstract: Various systems, method and apparatuses are disclosed that include a pressure swing adsorption apparatus coupled to a fuel cell, wherein the fuel cell receives at least a portion of a product gas from the pressure swing adsorption and powers the pressure swing adsorption apparatus. Also disclosed is a portable gas separator that include a housing that houses a rotary pressure swing adsorption apparatus.

Abstract: The electrochemical performance of an ion-exchange membrane in a fuel cell system may be improved by impregnating therein a perfluoroamine. The amine may be primary, secondary or tertiary. Further, the amine is preferably water insoluble or only slightly water soluble. For example, the amine may be perfluorotriamylamine or perfluorotributylamine. Use of such a membrane system within a fuel cell may allow high or low temperature operation (i.e. at temperatures greater than 100° C. or less than 0° C.) as well as operation at low relative humidity.

Abstract: A method and apparatus increase the temperature of a fuel cell via reactant starvation at one or both electrodes. Reactant starvation at an electrode results in an increased overvoltage at the electrode and hence increased internal heat generation under load. Further, starvation techniques may be used to prevent poisoning of electrode catalysts, a potential problem that is aggravated at lower temperatures. Starvation conditions can be prolonged or intermittent and can be obtained, for example, by suitably reducing the supply rate of a reactant or by operating the fuel cell at sufficiently high current density so as to consume reactant faster than it is supplied. The method can allow for some generation of useful power by the fuel cell during start-up. The method is particularly suitable for starting up a solid polymer electrolyte fuel cell from temperatures below 0° C.

Abstract: Liquid cooled systems having coolant circulation loops must often operate in below freezing conditions. For instance, in various applications certain fuel cell systems must be able to tolerate repeated shutdown and storage in below freezing conditions. Conventional glycol-based coolants typically used for internal combustion engines are generally unsuitable for use in the associated fuel cell cooling subsystems due to the presence of additives and/or inhibitors which are normally included to deal with problems relating to decomposition of the glycol. With additives or inhibitors present, the coolant conductivity can be sufficiently high as to result in electrical shorting or corrosion problems. However, provided the purity of the coolant is maintained, a pure glycol and water coolant mixture may be used as a fuel cell system coolant to obtain suitable antifreeze protection. Adequate purity can be maintained by including an ion exchange resin unit in the cooling subsystem.

Abstract: A method and apparatus increase the temperature of a fuel cell via reactant starvation at one or both electrodes. Reactant starvation at an electrode results in increased internal heat generation under load. Starvation conditions can be prolonged or intermittent and can be obtained, for example, by suitably reducing the supply rate of a reactant or by operating the fuel cell at sufficiently high current density so as to consume reactant faster than it is supplied. The method can allow for some generation of useful power by the fuel cell during start-up. The method is particularly suitable for starting up a solid polymer electrolyte fuel cell from temperatures below 0° C.

Abstract: The electrochemical performance of an ion-exchange membrane in a fuel cell system may be improved by impregnating therein a perfluoroamine. The amine may be primary, secondary or tertiary. Further, the amine is preferably water insoluble or only slightly water soluble. For example, the amine may be perfluorotriamylamine or perfluorotributylamine. Use of such a membrane system within a fuel cell may allow high or low temperature operation (i.e. at temperatures greater than 100° C. or less than 0° C.) as well as operation at low relative humidity.

Abstract: A method of controlling the temperature within an electrochemical fuel cell stack comprises introducing a reactant fluid stream comprising both a heat transfer liquid and a reactant into a fuel cell assembly such that the reactant fluid stream contacts an electrode. The heat transfer liquid is other than water. Preferably, the method further comprises recirculating heat transfer liquid which is in the reactant exhaust stream, typically via a heat exchanger, and re-introducing it into the fuel cell assembly in the reactant fluid stream. The recirculated heat transfer liquid may be directed to a reservoir which in turn supplies heat transfer liquid to the reactant fluid stream as it is needed. In a further embodiment, the method may comprise using the heat transfer liquid to heat a fuel cell stack to a desired operating temperature rather than cooling the stack.