Abstract: A method of forming a leak tight connection between a pipe and a port made of different metals is described. A leak tight connection between a pipe made of a first metal and a port made of a second metal is also described.

Abstract: A system and method for determining whether a hydrogen concentration sensor in the exhaust of a fuel cell system is operating properly during operation of the system. The method includes injecting hydrogen gas pulses from an injector directly into the system exhaust and analyzing a sensor response from those hydrogen injection pulses. Alternately, pulses from anode purges or bleeds can be provided to the exhaust to determine sensor response.

Abstract: A high pressure tank that has particular application for storing hydrogen gas on a vehicle for a fuel cell system. The tank includes a gas tight inner liner layer and a fiber bundle outer composite structural layer. A first strain gauge is provided in the outer layer and a second strain gauge is provided in the inner liner layer both proximate a transition between the layers. The strain gauges are calibrated relative to each other to identify the pressure where the inner liner layer begins to shrink and separate from the outer composite layer.

Abstract: A method of forming a leak tight connection between a pipe and a port made of different metals is described. A leak tight connection between a pipe made of a first metal and a port made of a second metal is also described.

Abstract: A hydrogen sensor assembly is disclosed. The hydrogen sensor assembly includes a sensing element within a sensor housing. The sensor housing includes an opening to facilitate a fluid communication between the sensing element and an exhaust stream of a fuel cell. A substantially water-vapor-impermeable membrane is disposed within the opening between the sensing element and the exhaust stream to militate against water vapor from the exhaust stream entering the sensor housing. The sensor housing may include a second opening to facilitate a fluid communication between the sensing element and an external environment to evacuate water vapor generated by the sensing element.

Abstract: A high pressure tank that has particular application for storing hydrogen gas on a vehicle for a fuel cell system. The tank includes a gas tight inner liner layer and a fiber bundle outer composite structural layer. A first strain gauge is provided in the outer layer and a second strain gauge is provided in the inner liner layer both proximate a transition between the layers. The strain gauges are calibrated relative to each other to identify the pressure where the inner liner layer begins to shrink and separate from the outer composite layer.

Abstract: A system and method for determining whether a hydrogen concentration sensor in the exhaust of a fuel cell system is operating properly during operation of the system. The method includes injecting hydrogen gas pulses from an injector directly into the system exhaust and analyzing a sensor response from those hydrogen injection pulses. Alternately, pulses from anode purges or bleeds can be provided to the exhaust to determine sensor response.

Abstract: A hydrogen sensor assembly is disclosed. The hydrogen sensor assembly includes a sensing element within a sensor housing. The sensor housing includes an opening to facilitate a fluid communication between the sensing element and an exhaust stream of a fuel cell. A substantially water-vapor-impermeable membrane is disposed within the opening between the sensing element and the exhaust stream to militate against water vapor from the exhaust stream entering the sensor housing. The sensor housing may include a second opening to facilitate a fluid communication between the sensing element and an external environment to evacuate water vapor generated by the sensing element.