Abstract: A proton exchange membrane fuel cell has a unit cell assembly including an anode side and a cathode side. The anode side has a cooling base plate, a conductor assembly, a hydrogen flow field, a water absorbing element, and a hydrogen duct assembly. The cathode side has an air flow field, a conductor assembly, an air flow distributor, and an insulating compression plate with wing extensions. A membrane electrode assembly is disposed between the anode side and the cathode side physically connecting the flow fields on both the anode and cathode sides. A sealed anode assembly creates a sealed hydrogen volume and includes the anode conductor assembly, the hydrogen duct assembly, and the membrane electrode assembly all disposed between the insulating compression plate and the cooling base plate. The fuel cell may comprise multiple unit cell assemblies arranged in planar, folded, stacked, or pancake configurations.

Abstract: A system for sensing a gas stream constituent comprises: (a) a thermally conductive, electrically insulative substrate, (b) a gas-sensing element mounted on the substrate and capable of sensing the constituent, (c) a reference element mounted on the substrate having electrical properties congruent with the gas-sensing element and being insensitive to the constituent, (d) an electronic circuit interconnecting the gas-sensing element and the reference element. The circuit is capable of actuating both of the elements and measuring the voltage difference between the elements. The voltage difference is proportional to the concentration of the constituent in the gas stream.

Abstract: A proton exchange membrane fuel cell has a unit cell assembly including an anode side and a cathode side. The anode side has a cooling base plate, a conductor assembly, a hydrogen flow field, a water absorbing element, and a hydrogen duct assembly. The cathode side has an air flow field, a conductor assembly, an air flow distributor, and an insulating compression plate with wing extensions. A membrane electrode assembly is disposed between the anode side and the cathode side physically connecting the flow fields on both the anode and cathode sides. A sealed anode assembly creates a sealed hydrogen volume and includes the anode conductor assembly, the hydrogen duct assembly, and the membrane electrode assembly all disposed between the insulating compression plate and the cooling base plate. The fuel cell may comprise multiple unit cell assemblies arranged in planar, folded, stacked, or pancake configurations.

Abstract: A gas sensor for sensing a gas stream constituent includes, mounted a substrate, a first gas-sensing element capable of sensing the constituent in a first concentration range, a reference element insensitive to the constituent and having electrical properties congruent with the first gas-sensing element, a heating element substantially circumscribing the first gas-sensing element and the reference element, a temperature-sensing element circumscribing the first gas-sensing element and the reference element, and a second gas-sensing element capable of sensing the constituent in a second concentration range. The first gas-sensing element and the reference element are preferably metal-gated metal-oxide semiconductor (MOS) solid-state devices. The gas sensor is particularly configured to sense hydrogen concentration in a gas stream.

Abstract: A gas sensor assembly detects the presence of a constituent in a first gas stream. The assembly comprises: (a) a flexible circuit having a pair of oppositely-facing surfaces, (b) a sensor mounted on one surface of the flex circuit, the sensor electrically connected to conductors in the flex circuit, and (c) a channel for directing a second gas stream across the flex circuit surface facing away from the sensor, the channel formed at least in part by the flex circuit surface facing away from the sensor. The first and second gas streams can be derived from a common gas stream. In operation, thermal conductivity between the sensor and neighboring heat-conducting structures components is reduced, thereby reducing sensor electric power consumption.

Abstract: A proton exchange membrane fuel cell has a unit cell assembly including an anode side and a cathode side. The anode side has a cooling base plate, a conductor assembly, a hydrogen flow field, a water absorbing element, and a hydrogen duct assembly. The cathode side has an air flow field, a conductor assembly, an air flow distributor, and an insulating compression plate with wing extensions. A membrane electrode assembly is disposed between the anode side and the cathode side physically connecting the flow fields on both the anode and cathode sides. A sealed anode assembly creates a sealed hydrogen volume and includes the anode conductor assembly, the hydrogen duct assembly, and the membrane electrode assembly all disposed between the insulating compression plate and the cooling base plate. The fuel cell may comprise multiple unit cell assemblies arranged in planar, folded, stacked, or pancake configurations.

Abstract: A gas sensor for sensing a gas stream constituent includes, mounted a substrate, a first gas-sensing element capable of sensing the constituent in a first concentration range, a reference element insensitive to the constituent and having electrical properties congruent with the first gas-sensing element, a heating element substantially circumscribing the first gas-sensing element and the reference element, a temperature-sensing element circumscribing the first gas-sensing element and the reference element, and a second gas-sensing element capable of sensing the constituent in a second concentration range. The first gas-sensing element and the reference element are preferably metal-gated metal-oxide semiconductor (MOS) solid-state devices. The gas sensor is particularly configured to sense hydrogen concentration in a gas stream.

Abstract: A gas sensor for sensing a gas stream constituent includes, mounted a substrate, a first gas-sensing element capable of sensing the constituent in a first concentration range, a reference element insensitive to the constituent and having electrical properties congruent with the first gas-sensing element, a heating element substantially circumscribing the first gas-sensing element and the reference element, a temperature-sensing element circumscribing the first gas-sensing element and the reference element, and a second gas-sensing element capable of sensing the constituent in a second concentration range. The first gas-sensing element and the reference element are preferably metal-gated metal-oxide semiconductor (MOS) solid-state devices. The gas sensor is particularly configured to sense hydrogen concentration in a gas stream.

Abstract: A gas sensor assembly detects the presence of a constituent in a first gas stream. The assembly comprises: (a) a flexible circuit having a pair of oppositely-facing surfaces, (b) a sensor mounted on one surface of the flex circuit, the sensor electrically connected to conductors in the flex circuit, and (c) a channel for directing a second gas stream across the flex circuit surface facing away from the sensor, the channel formed at least in part by the flex circuit surface facing away from the sensor. The first and second gas streams can be derived from a common gas stream. In operation, thermal conductivity between the sensor and neighboring heat-conducting structures components is reduced, thereby reducing sensor electric power consumption.

Abstract: A system for sensing a gas stream constituent comprises: (a) a thermally conductive, electrically insulative substrate, (b) a gas-sensing element mounted on the substrate and capable of sensing the constituent, (c) a reference element mounted on the substrate having electrical properties congruent with the gas-sensing element and being insensitive to the constituent, (d) an electronic circuit interconnecting the gas-sensing element and the reference element. The circuit is capable of actuating both of the elements and measuring the voltage difference between the elements. The voltage difference is proportional to the concentration of the constituent in the gas stream.

Abstract: A gas sensor for sensing a gas stream constituent includes, mounted a substrate, a first gas-sensing element capable of sensing the constituent in a first concentration range, a reference element insensitive to the constituent and having electrical properties congruent with the first gas-sensing element, a heating element substantially circumscribing the first gas-sensing element and the reference element, a temperature-sensing element circumscribing the first gas-sensing element and the reference element, and a second gas-sensing element capable of sensing the constituent in a second concentration range. The first gas-sensing element and the reference element are preferably metal-gated metal-oxide semiconductor (MOS) solid-state devices. The gas sensor is particularly configured to sense hydrogen concentration in a gas stream.