Abstract: A fuel cell flow field plate includes an aluminum substrate plate having a first side and a second side wherein the first side of the aluminum substrate plate defines a plurality of channels for transporting a first fuel cell reactant gas. The flow field plate also includes a first metal interlayer deposited on the first side of the aluminum substrate plate, a second metal interlayer deposited on the second side of the aluminum substrate plate, a first amorphous carbon layer deposited on the first metal interlayer, and a second amorphous carbon layer deposited on the second metal interlayer. The first amorphous carbon layer and second amorphous carbon layer each independently have a density greater than or equal to 1.2 g/cc.

Abstract: A system and method for determining whether a concentration estimation value of hydrogen gas in an anode sub-system of a fuel cell system is within a predetermined threshold of a valid hydrogen gas concentration, and if not, correcting the estimation value. The method includes providing a hydrogen gas concentration sensor value from a virtual sensor and calculating the hydrogen gas concentration estimation value using a gas concentration estimation model. The method also includes determining if a difference between the estimation value and the sensor value is greater than at least one threshold, and if so, causing an extended bleed event to occur that bleeds an anode exhaust gas to force the estimation value to be closer to the sensor value. The method also includes setting a diagnostic if multiple extended bleeds do not cause the estimation value and the sensor value to converge.

Abstract: A fuel cell flow field plate includes an aluminum substrate plate having a first side and a second side wherein the first side of the aluminum substrate plate defines a plurality of channels for transporting a first fuel cell reactant gas. The flow field plate also includes a first metal interlayer deposited on the first side of the aluminum substrate plate, a second metal interlayer deposited on the second side of the aluminum substrate plate, a first amorphous carbon layer deposited on the first metal interlayer, and a second amorphous carbon layer deposited on the second metal interlayer. The first amorphous carbon layer and second amorphous carbon layer each independently have a density greater than or equal to 1.2 g/cc.

Abstract: A system and method for determining whether a concentration estimation value of hydrogen gas in an anode sub-system of a fuel cell system is within a predetermined threshold of a valid hydrogen gas concentration, and if not, correcting the estimation value. The method includes providing a hydrogen gas concentration sensor value from a virtual sensor and calculating the hydrogen gas concentration estimation value using a gas concentration estimation model. The method also includes determining if a difference between the estimation value and the sensor value is greater than at least one threshold, and if so, causing an extended bleed event to occur that bleeds an anode exhaust gas to force the estimation value to be closer to the sensor value. The method also includes setting a diagnostic if multiple extended bleeds do not cause the estimation value and the sensor value to converge.

Abstract: A bipolar plate used in a fuel cell and a method of making a bipolar plate. The sheet is made generally from a stainless steel, and in a more preferable form from a ferritic stainless steel. In one configuration, a stamping or related metal forming tool operation will introduce a negative clearance as a way to move or otherwise reallocate a portion of the material making up the sheet into other portions as a way to reduce stretching, necking, thinning and related thickness deviations associated with the bends formed in the bipolar plate.

Abstract: A bipolar plate used in a fuel cell and a method of making a bipolar plate. The sheet is made generally from a stainless steel, and in a more preferable form from a ferritic stainless steel. In one configuration, a stamping or related metal forming tool operation will introduce a negative clearance as a way to move or otherwise reallocate a portion of the material making up the sheet into other portions as a way to reduce stretching, necking, thinning and related thickness deviations associated with the bends formed in the bipolar plate.