A fuel cell single unit including: a fuel cell element in which an anode layer and a cathode layer are formed so as to sandwich an electrolyte layer; a reducing gas supply path for supplying a gas containing hydrogen to the anode layer; an oxidizing gas supply path for supplying a gas containing oxygen to the cathode layer; and an internal reforming catalyst layer, which has a reforming catalyst for steam-reforming a fuel gas, in at least a part of the reducing gas supply path is provided. An external reformer, which has a reforming catalyst for steam-reforming the fuel gas, is provided upstream of the reducing gas supply path, and the fuel gas partially reformed by the external reformer is supplied to the reducing gas supply path.

A fuel cell single unit including: a fuel cell element in which an anode layer and a cathode layer are formed so as to sandwich an electrolyte layer; a reducing gas supply path for supplying a gas containing hydrogen to the anode layer; an oxidizing gas supply path for supplying a gas containing oxygen to the cathode layer; and an internal reforming catalyst layer, which has a reforming catalyst for steam-reforming a fuel gas, in at least a part of the reducing gas supply path is provided. An external reformer, which has a reforming catalyst for steam-reforming the fuel gas, is provided upstream of the reducing gas supply path, and the fuel gas partially reformed by the external reformer is supplied to the reducing gas supply path.

Provided are a metal plate configured such that sufficient strength and performance are ensured and the workability and cost of mass production are improved, and an electrochemical element and the like including the metal plate. A metal plate 1 includes a thick portion 110, and a thin portion 120 that is thinner than the thick portion 110. The thin portion 120 is provided with a penetration space 1c passing through the thin portion 120 in the thickness direction.

Provided are a metal plate configured such that sufficient strength and performance are ensured and the workability and cost of mass production are improved, and an electrochemical element and the like including the metal plate. A metal plate 1 includes a thick portion 110, and a thin portion 120 that is thinner than the thick portion 110. The thin portion 120 is provided with a penetration space 1c passing through the thin portion 120 in the thickness direction.

A method of manufacturing a proton-conducting fuel cell includes assembling a green anode-electrolyte half-cell by forming an anode substrate layer having an upper surface and a lower surface, forming an anode functional layer on the upper surface of the anode substrate layer, forming an electrolyte layer on an upper surface of the anode functional layer, and forming a stress balancing layer on the lower surface of the anode substrate layer. The method further includes positioning the green anode-electrolyte half-cell on kiln furniture inside a sintering kiln and sintering the green anode-electrolyte half-cell using SSRS to an anode-electrolyte half-cell.

A composite including an electrolyte layer containing solid oxide, and at least one electrode selected from a cathode disposed on one side of the electrolyte layer in a first direction and an anode disposed on the other side of the electrolyte layer in the first direction. Either one of two surfaces of the composite located on opposite sides in the first direction satisfies a first requirement that, as viewed in the first direction, a curvature determined on the basis of any three points juxtaposed at intervals of 5 mm is less than 0.0013 (l/mm) and that, as viewed in a second direction perpendicular to the first direction, the curvature is the reciprocal of the radius of an imaginary circle passing through the any three points.

A composite including an electrolyte layer containing solid oxide, and at least one electrode selected from a cathode disposed on one side of the electrolyte layer in a first direction and an anode disposed on the other side of the electrolyte layer in the first direction. Either one of two surfaces of the composite located on opposite sides in the first direction satisfies a first requirement that, as viewed in the first direction, a curvature determined on the basis of any three points juxtaposed at intervals of 5 mm is less than 0.0013 (l/mm) and that, as viewed in a second direction perpendicular to the first direction, the curvature is the reciprocal of the radius of an imaginary circle passing through the any three points.

Disclosed is a method of making an electrochemical cell, comprising: depositing an anode layer on a surface of a porous metal support layer; depositing an electrolyte layer on a surface of the anode layer, wherein the electrolyte layer is deposited via suspension plasma spray, wherein the electrolyte layer conducts protons; and depositing a cathode layer on a surface of the electrolyte layer. Also disclosed is a stack comprising two or more of the electrochemical cell.

Disclosed is a method of making an electrochemical cell, comprising: depositing an anode layer on a surface of a porous metal support layer; depositing an electrolyte layer on a surface of the anode layer, wherein the electrolyte layer is deposited via suspension plasma spray, wherein the electrolyte layer conducts protons; and depositing a cathode layer on a surface of the electrolyte layer. Also disclosed is a stack comprising two or more of the electrochemical cell.

An electrochemical cell includes a porous support substrate and a power generation element portion. The support substrate includes at least one first gas channel and at least one second gas channel. The first gas channel extends from a first end portion toward a second end portion and is connected to a gas supply chamber. The second gas channel is connected to the first gas channel on the second end portion side. The second gas channel extends from the second end portion toward the first end portion and is connected to a gas collection chamber. A ratio (p0/L) of a pitch p0 of a first gas channel and a second gas channel that are adjacent to each other to a distance L between the power generation element portion and a first end surface of the support substrate located on the first end portion side is 3.3 or less.