Abstract: Methods and systems for measuring and/or estimating a coefficient of thermal expansion (CTE) of a component of a fuel cell system. A CTE measurement technique includes securing a measurement member over a surface of the component via a seal having a melting point, heating the seal above its melting point of the seal, cooling the component, measurement member and seal to a second temperature below the melting point of the seal, and determining the CTE of the component based on the change in the span of the measurement member after cooling. A fuel cell component characterization technique includes measuring an electrical resistivity (ER), conductivity (EC), resistance or conductance of the component, measuring at least one additional property of the component which, together with ER, EC, resistance or conductance, correlates to the CTE of the component, and sorting the component based on the measurements.

Abstract: A seal ring in the form of a grooved ring for sealing a movable machine element toward a stationary housing includes: a radially inner axial leg with a dynamic sealing edge; a radially outer axial leg with a static sealing edge; and a radial leg connecting the two axial legs. The seal ring is produced from a thermoplastic material. A recess is formed between the two axial legs and the radial leg. The radially inner axial leg has, on a surface of the radially inner axial leg on a machine element side, a rounded transition to a surface of the radial leg that faces away from a pressure.

Abstract: Methods and systems for measuring and/or estimating a coefficient of thermal expansion (CTE) of a component of a fuel cell system. A CTE measurement technique includes securing a measurement member over a surface of the component via a seal having a melting point, heating the seal above its melting point of the seal, cooling the component, measurement member and seal to a second temperature below the melting point of the seal, and determining the CTE of the component based on the change in the span of the measurement member after cooling. A fuel cell component characterization technique includes measuring an electrical resistivity (ER), conductivity (EC), resistance or conductance of the component, measuring at least one additional property of the component which, together with ER, EC, resistance or conductance, correlates to the CTE of the component, and sorting the component based on the measurements.

Abstract: Methods and systems for measuring and/or estimating a coefficient of thermal expansion (CTE) of a component of a fuel cell system. A CTE measurement technique includes securing a measurement member over a surface of the component via a seal having a melting point, heating the seal above its melting point of the seal, cooling the component, measurement member and seal to a second temperature below the melting point of the seal, and determining the CTE of the component based on the change in the span of the measurement member after cooling. A fuel cell component characterization technique includes measuring an electrical resistivity (ER), conductivity (EC), resistance or conductance of the component, measuring at least one additional property of the component which, together with ER, EC, resistance or conductance, correlates to the CTE of the component, and sorting the component based on the measurements.

Abstract: Various embodiments include interconnects and/or end plates having features for reducing stress in a fuel cell stack. In embodiments, an interconnect/end plate may have a window seal area that is recessed relative to the flow field to indirectly reduce stress induced by an interface seal. Other features may include a thicker protective coating and/or larger uncoated area of an end plate, providing a recessed portion on an end plate for an interface seal, and/or recessing the fuel hole region of an interconnect relative to the flow field to reduce stress on the fuel cell. Further embodiments include providing intermittent seal support to minimize asymmetric seal loading and/or a non-circular seal configuration to reduce stress around the fuel hole of a fuel cell.

Abstract: Various embodiments include interconnects and/or end plates having features for reducing stress in a fuel cell stack. In embodiments, an interconnect/end plate may have a window seal area that is recessed relative to the flow field to indirectly reduce stress induced by an interface seal. Other features may include a thicker protective coating and/or larger uncoated area of an end plate, providing a recessed portion on an end plate for an interface seal, and/or recessing the fuel hole region of an interconnect relative to the flow field to reduce stress on the fuel cell. Further embodiments include providing intermittent seal support to minimize asymmetric seal loading and/or a non-circular seal configuration to reduce stress around the fuel hole of a fuel cell.