Abstract: A fuel cell stack fuel plenum includes a base plate including an inlet hole and an outlet hole, a dielectric layer disposed on the base plate and including an inlet hole and an outlet hole, a cover plate disposed on the dielectric layer and including an inlet hole and an outlet hole, a seal plate disposed on the cover plate and including an inlet hole and an outlet hole, and a manifold plate disposed on the seal plate. The manifold plate includes a bottom inlet hole and a bottom outlet hole formed in a bottom surface of the manifold plate, top outlet holes and top inlet holes formed in opposing sides of a top surface of the manifold plate, outlet channels fluidly connecting the top outlet holes to the bottom inlet hole, and inlet channels fluidly connecting the top inlet holes to the bottom outlet hole.

Abstract: A method of operating a fuel cell system includes providing fuel to a fuel cell column located in a hotbox, providing a column air stream to the fuel cell column and a separate anode tail gas oxidizer (ATO) air stream to an ATO located in the hotbox, where the ATO air stream bypasses the fuel cell column, and providing an anode exhaust from the fuel cell column to the ATO.

Abstract: A fuel cell stack fuel plenum includes a base plate including an inlet hole and an outlet hole, a dielectric layer disposed on the base plate and including an inlet hole and an outlet hole, a cover plate disposed on the dielectric layer and including an inlet hole and an outlet hole, a seal plate disposed on the cover plate and including an inlet hole and an outlet hole, and a manifold plate disposed on the seal plate. The manifold plate includes a bottom inlet hole and a bottom outlet hole formed in a bottom surface of the manifold plate, top outlet holes and top inlet holes formed in opposing sides of a top surface of the manifold plate, outlet channels fluidly connecting the top outlet holes to the bottom inlet hole, and inlet channels fluidly connecting the top inlet holes to the bottom outlet hole.

Abstract: A fuel cell system includes a plurality of fuel cell segments, each segment having a plurality of fuel cells. The segments include a positive terminal having a positive voltage with respect to ground and a negative terminal. The fuel cell system also includes at least one component electrically connecting the negative terminal to ground, the at least one component configured to decrease a surge current through the segments.

Abstract: A method of operating an electrolyzer module includes providing a first air stream and steam into a stack of electrolyzer cells located in a hotbox and outputting a product stream containing hydrogen and steam, and an oxygen exhaust stream, providing the product stream to an internal product cooler (IPC) heat exchanger located in the hotbox to reduce the temperature of the product stream by transferring heat to the first air stream, and providing the product stream from the IPC to an external product cooler (EPC) heat exchanger located outside of the hotbox and inside of a cabinet housing the hotbox to further reduce the temperature of the product stream by transferring heat to a fluid stream.

Abstract: A method of operating an electrolyzer module includes providing a first air stream and steam into a stack of electrolyzer cells located in a hotbox and outputting a product stream containing hydrogen and steam, and an oxygen exhaust stream, providing the product stream to an internal product cooler (IPC) heat exchanger located in the hotbox to reduce the temperature of the product stream by transferring heat to the first air stream, and providing the product stream from the IPC to an external product cooler (EPC) heat exchanger located outside of the hotbox and inside of a cabinet housing the hotbox to further reduce the temperature of the product stream by transferring heat to a fluid stream.

Abstract: An electrolyzer system includes a splitter configured to split a first air inlet stream into a bypass air stream and a second air inlet stream, a stack of electrolyzer cells configured receive steam and the second air inlet stream and output a product stream containing hydrogen and an oxygen exhaust stream, such that the bypass air stream is configured to bypass the stack, and a product cooler heat exchanger configured to cool the product stream using the first air inlet stream.

Abstract: An electrolyzer system includes a splitter configured to split a first air inlet stream into a bypass air stream and a second air inlet stream, a stack of electrolyzer cells configured receive steam and the second air inlet stream and output a product stream containing hydrogen and an oxygen exhaust stream, such that the bypass air stream is configured to bypass the stack, and a product cooler heat exchanger configured to cool the product stream using the first air inlet stream.

Abstract: An electrolyzer system includes a splitter configured to split a first air inlet stream into a bypass air stream and a second air inlet stream, a stack of electrolyzer cells configured receive steam and the second air inlet stream and output a product stream containing hydrogen and an oxygen exhaust stream, such that the bypass air stream is configured to bypass the stack, and a product cooler heat exchanger configured to cool the product stream using the first air inlet stream.

Abstract: An electrolyzer system includes electrolyzer cell columns each containing at least one stack of electrolyzer cells that are configured to receive a steam inlet stream and an air inlet stream, and to generate a hydrogen exhaust stream and an oxygen exhaust stream, an air recuperator heat exchanger surrounded by the electrolyzer cell columns and configured to heat the air inlet stream using the oxygen exhaust stream, a steam recuperator heat exchanger surrounded by the electrolyzer cell columns and configured to heat the steam inlet stream using the hydrogen exhaust stream, an outer column heater located radially outward of the electrolyzer cell columns and configured to radiate heat toward radially outward surfaces of the electrolyzer cell columns, and an inner column heater located radially inward of the electrolyzer cell columns, surrounding the air recuperator heat exchanger and the steam recuperator heat exchanger, and configured to radiate heat toward radially inward surfaces of the electrolyzer cell colu

Abstract: An electrochemical cell system includes electrochemical cell columns arranged in an annular configuration over a support, each cell column having a front side that faces away from a center of the annular configuration, a back side that faces the center of the annular configuration, and opposing first and second sides that connect the front and back sides, and multi-component baffle assemblies located between adjacent cell columns and including at least one air bypass mitigation feature configured to reduce or prevent air from flowing between the cell columns.

Abstract: A fuel cell system includes a fuel cell stack, an anode tail gas oxidizer (ATO), an ATO injector configured to mix a first portion of an anode exhaust from the fuel cell stack with a cathode exhaust from the fuel cell stack and to provide a mixture of the first portion of the anode exhaust and the cathode exhaust into the ATO, an anode exhaust conduit which is configured to provide the first portion of the anode exhaust into the ATO injector, and cathode exhaust conduit which is configured to provide at least a portion of the cathode exhaust from the fuel cell stack into the ATO injector. The ATO injector includes injector tubes or injection apertures.

Abstract: A method of operating a fuel cell system includes providing an anode exhaust stream from a stack of fuel cells into an anode exhaust cooler, providing an air inlet stream into the anode exhaust cooler and heating the air inlet stream using heat extracted from the anode exhaust stream, providing a heated air inlet stream output from the anode exhaust cooler into the stack, providing a cooled anode exhaust stream at a temperature between 110° C. and 180° C. from the anode exhaust cooler into an anode recycle blower, and recycling at least a portion of the cooled anode exhaust stream into a fuel inlet stream provided into the stack.

Abstract: A fuel cell column includes a stack of alternating fuel cells and interconnects, where the interconnects separate adjacent fuel cells in the stack and contain fuel and air channels which are configured to provide respective fuel and air to the fuel cells. a manifold plate containing a bottom inlet hole and a bottom outlet hole located in a bottom surface of the manifold plate, top outlet holes and top inlet holes formed in opposing sides of a top surface of the manifold plate, outlet channels fluidly connecting the top outlet holes to the bottom inlet hole, and inlet channels fluidly connecting the top inlet holes to the bottom outlet hole, and a mitigation structure configured to reduce stress applied to the stack due to at least one of a shape mismatch or coefficient of thermal expansion mismatch between the stack and the manifold plate.

Abstract: A fuel cell system includes a stack of fuel cells, a cathode recuperator configured to heat air using cathode exhaust output from the stack, and an air inlet baffle disposed between the cathode recuperator and the stack and containing at least two rows of apertures which are separated along a vertical direction and configured to provide the heated air output from the cathode recuperator to plural areas of the stack.

Abstract: A method of operating a fuel cell system includes providing an anode exhaust from a fuel cell stack to a water injector, supplying water to the water injector, and injecting the water from the water injector into the anode exhaust to vaporize the water and generate a humidified anode exhaust.

Abstract: A fuel cell column includes a stack of alternating fuel cells and interconnects, where the interconnects separate adjacent fuel cells in the stack and contain fuel and air channels which are configured to provide respective fuel and air to the fuel cells. a manifold plate containing a bottom inlet hole and a bottom outlet hole located in a bottom surface of the manifold plate, top outlet holes and top inlet holes formed in opposing sides of a top surface of the manifold plate, outlet channels fluidly connecting the top outlet holes to the bottom inlet hole, and inlet channels fluidly connecting the top inlet holes to the bottom outlet hole, and a mitigation structure configured to reduce stress applied to the stack due to at least one of a shape mismatch or coefficient of thermal expansion mismatch between the stack and the manifold plate.

Abstract: A fuel cell system includes a fuel cell stack, an anode tail gas oxidizer (ATO), an ATO injector configured to mix a first portion of an anode exhaust from the fuel cell stack with a cathode exhaust from the fuel cell stack and to provide a mixture of the first portion of the anode exhaust and the cathode exhaust into the ATO, an anode exhaust conduit which is configured to provide the first portion of the anode exhaust into the ATO injector, and cathode exhaust conduit which is configured to provide at least a portion of the cathode exhaust from the fuel cell stack into the ATO injector. The ATO injector includes injector tubes or injection apertures.

Abstract: A fuel cell system includes a fuel cell stack, an anode tail gas oxidizer (ATO), an ATO injector configured to mix a first portion of an anode exhaust from the fuel cell stack with a cathode exhaust from the fuel cell stack and to provide a mixture of the first portion of the anode exhaust and the cathode exhaust into the ATO, an anode exhaust conduit which is configured to provide the first portion of the anode exhaust into the ATO injector, and cathode exhaust conduit which is configured to provide at least a portion of the cathode exhaust from the fuel cell stack into the ATO injector. The ATO injector includes injector tubes or injection apertures.

Abstract: A fuel cell stack fuel plenum includes a base plate including an inlet hole and an outlet hole, a dielectric layer disposed on the base plate and including an inlet hole and an outlet hole, a cover plate disposed on the dielectric layer and including an inlet hole and an outlet hole, a seal plate disposed on the cover plate and including an inlet hole and an outlet hole, and a manifold plate disposed on the seal plate. The manifold plate includes a bottom inlet hole and a bottom outlet hole formed in a bottom surface of the manifold plate, top outlet holes and top inlet holes formed in opposing sides of a top surface of the manifold plate, outlet channels fluidly connecting the top outlet holes to the bottom inlet hole, and inlet channels fluidly connecting the top inlet holes to the bottom outlet hole.