Abstract: A method of forming a fuel cell interconnect includes depositing a Cr alloy powder, sintering the Cr alloy powder, and repeating the depositing and the sintering to form the fuel cell interconnect. The Cr alloy powder may include a pre-alloyed powder containing from about 4 wt. % to about 6 wt. % Fe, and from about 94 wt. % to about 96 wt. % Cr.

Abstract: A method of forming a protective coating on an interconnect for an electrochemical device stack includes providing a powder on the interconnect and laser sintering the powder.

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 method of operating a fuel cell power system includes providing a fresh hydrogen fuel to power modules that each contain a heater and a stack of fuel cells, providing a fuel exhaust containing hydrogen and water from the stack to a condenser, removing water from the fuel exhaust to generate a recycled fuel containing dewatered hydrogen, and pressurizing and recycling the recycled fuel output from the condenser to the power modules. The removed water may be vaporized in a stack cathode exhaust.

Abstract: A fuel cell system column includes a first terminal plate connected to a first electrical output of the column, a second terminal plate connected to a second electrical output of the column, at least one first fuel cell stack located in a middle portion of the column between the first terminal plate and the second terminal plate, and at least one electrical connection which is electrically connected to the middle portion of the column and which is configured to provide a more uniform fuel utilization across the first column.

Abstract: A fuel cell interconnect includes fuel ribs disposed on a first side of the interconnect and a least partially defining fuel channels, and air ribs disposed on an opposing second side of the interconnect and at least partially defining air channels. The fuel channels include central fuel channels disposed in a central fuel field and peripheral fuel channels disposed in peripheral fuel fields disposed on opposing sides of the central fuel field. The air channels include central air channels disposed in a central air field and peripheral air channels disposed in peripheral air fields disposed on opposing sides of the central air field. At least one of the central fuel channels or the central air channels has at least one of a different cross-sectional area or length than at least one of the respective peripheral fuel channels or the respective peripheral air channels.

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 method of making an interconnect for a solid oxide fuel cell stack includes contacting an interconnect powder located in a die cavity with iron, the interconnect powder including a chromium and iron, compressing the interconnect powder to form an interconnect having ribs and fuel channels on a first side of the interconnect, such that the iron is disposed on tips of the ribs; and sintering the interconnect, such that the iron forms an contact layer on the tips of the ribs having a higher iron concentration than a remainder of the interconnect. A glass containing cathode contact layer having a glass transition temperature of 900° C. or less may be located over the rib tips on the oxidant side of the interconnect.

Abstract: A method of making an interconnect for a solid oxide fuel cell stack includes providing an iron rich material containing at least 25 wt. % iron into channels of a mold, providing a powder containing 4-6 wt. % Fe, 0-1 wt. % Y and balance Cr into the mold over the iron rich material containing at least 25 wt. % iron, compacting the iron rich material containing at least 25 wt. % iron and the powder comprising 4-6 wt. % Fe, 0-1 wt. % Y and balance Cr in the mold to form the interconnect, and sintering the interconnect to form a sintered interconnect having iron rich regions having an iron concentration greater than 10% in ribs of the interconnect.

Abstract: A method of forming a fuel cell interconnect includes depositing a Cr alloy powder, sintering the Cr alloy powder, and repeating the depositing and the sintering to form the fuel cell interconnect. The Cr alloy powder may include a pre-alloyed powder containing from about 4 wt. % to about 6 wt. % Fe, and from about 94 wt. % to about 96 wt. % Cr.

Abstract: A fuel cell system column includes a first terminal plate connected to a first electrical output of the column, a second terminal plate connected to a second electrical output of the column, at least one first fuel cell stack located in a middle portion of the column between the first terminal plate and the second terminal plate, and at least one electrical connection which is electrically connected to the middle portion of the column and which is configured to provide a more uniform fuel utilization across the first column.

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 method of making an interconnect for a solid oxide fuel cell stack includes contacting an interconnect powder located in a die cavity with iron, the interconnect powder including a chromium and iron, compressing the interconnect powder to form an interconnect having ribs and fuel channels on a first side of the interconnect, such that the iron is disposed on tips of the ribs; and sintering the interconnect, such that the iron forms an contact layer on the tips of the ribs having a higher iron concentration than a remainder of the interconnect. A glass containing cathode contact layer having a glass transition temperature of 900° C. or less may be located over the rib tips on the oxidant side of the interconnect.

Abstract: A method of making an interconnect for a solid oxide fuel cell stack includes providing an iron rich material containing at least 25 wt. % iron into channels of a mold, providing a powder containing 4-6 wt. % Fe, 0-1 wt. % Y and balance Cr into the mold over the iron rich material containing at least 25 wt. % iron, compacting the iron rich material containing at least 25 wt. % iron and the powder comprising 4-6 wt. % Fe, 0-1 wt. % Y and balance Cr in the mold to form the interconnect, and sintering the interconnect to form a sintered interconnect having iron rich regions having an iron concentration greater than 10% in ribs of the interconnect.

Abstract: A method of making an interconnect for a solid oxide fuel cell stack includes contacting an interconnect powder located in a die cavity with iron, the interconnect powder including a chromium and iron, compressing the interconnect powder to form an interconnect having ribs and fuel channels on a first side of the interconnect, such that the iron is disposed on tips of the ribs; and sintering the interconnect, such that the iron forms an contact layer on the tips of the ribs having a higher iron concentration than a remainder of the interconnect. A glass containing cathode contact layer having a glass transition temperature of 900° C. or less may be located over the rib tips on the oxidant side of the interconnect.

Abstract: Methods for fabricating an interconnect for a fuel cell system that include forming a metal powder into a preform structure, positioning the preform structure in a die cavity of a press apparatus, and compressing the preform structure in the press apparatus to form the interconnect. Further embodiments include use of thin inserts in the die cavity to provide reduced permeability and/or including filler material in the die cavity.

Abstract: Various methods of treating a chromium iron interconnect for a solid oxide fuel cell stack and coating the interconnect with a ceramic layer are provided.

Abstract: Systems and methods for testing a fuel cell stack include a vacuum source, a test head including at least one isolated vacuum plenum configured to be positioned in fluid communication with a first portion of the fuel cell stack, the isolated vacuum plenum in fluid communication with the vacuum source, and a detector in fluid communication with the at least one isolated vacuum plenum for detecting the presence of a particular constituent of a fluid provided in a second portion of the fuel cell stack, where the second portion of the fuel cell stack is separated from the first portion of the fuel cell stack by at least one of an electrolyte and a fuel cell seal.

Abstract: Methods for fabricating an interconnect for a fuel cell stack that include providing a protective layer over at least one surface of an interconnect formed by powder pressing pre-alloyed particles containing two or more metal elements and annealing the interconnect and the protective layer at elevated temperature to bond the protective layer to the at least one surface of the interconnect.

Abstract: A method of making an interconnect for a solid oxide fuel cell stack includes contacting an interconnect powder located in a die cavity with iron, the interconnect powder including a chromium and iron, compressing the interconnect powder to form an interconnect having ribs and fuel channels on a first side of the interconnect, such that the iron is disposed on tips of the ribs; and sintering the interconnect, such that the iron forms an contact layer on the tips of the ribs having a higher iron concentration than a remainder of the interconnect. A glass containing cathode contact layer having a glass transition temperature of 900° C. or less may be located over the rib tips on the oxidant side of the interconnect.