Abstract: A fuel cell system including: an electrochemical pump including a first anode, a first cathode, and a first electrolyte membrane including a proton conductive oxide, the electrochemical pump separating hydrogen from a gas containing the hydrogen, and a solid oxide fuel cell that includes a second anode, a second cathode, and a second electrolyte membrane including a solid oxide electrolyte, and that generates electricity by reacting a fuel gas and an oxidant gas with each other.

Abstract: An electrode material of the present disclosure is an electrode material that includes a compound represented by the chemical formula BaZr1-x-yMxCoyO3-?. M is In or Yb, and the chemical formula satisfies 0<x<1, 0<y<1, 0<(x+y)<1, and 0<?<1. A membrane electrode assembly of the present disclosure includes a first electrode including the electrode material, and an electrolyte membrane provided on a first main surface of the first electrode.

Abstract: A proton conductor of the present disclosure includes a compound represented by the chemical formula BaZr(1-x-y)YbxScyO3-?. The chemical formula satisfies 0<x<0.5, 0 <y<0.5, (x+y)<0.5, and 0<?<0.5.

Abstract: A membrane electrode assembly of an electrochemical device includes a proton conductive solid electrolyte membrane and an electrode including Ni and an electrolyte material which contains as a primary component, at least one of a first compound having a composition represented by BaZr1-x1M1x1O3 (M1 represents at least one element selected from trivalent elements each having an ion radius of more than 0.720 A° to less than 0.880 A°, and 0<x1<1 holds) and a second compound having a composition represented by BaZr1-x2Tmx2O3 (0<x2<0.3 holds).

Abstract: The electrolyte membrane of the present disclosure includes a plurality of crystal domains. At least one of the crystal domains includes a first crystal subdomain and a second crystal subdomain. Each of the first crystal subdomain and the second crystal subdomain includes Ba, Zr, M, and O. M is a trivalent element. The concentration of M in the first crystal subdomain is different from the concentration of M in the second crystal subdomain.

Abstract: The fuel cell system of the present disclosure includes: a fuel cell that includes a membrane electrode assembly including a proton conducting ceramic electrolyte membrane, a cathode disposed on a first surface of the electrolyte membrane, and an anode disposed on a second surface of the electrolyte membrane, the fuel cell generating electric power through an electrochemical reaction using a fuel gas and an oxidant gas; a power source that applies a voltage to the fuel cell; and a controller. In a shutdown process, the controller controls the power source to apply the voltage to the fuel cell such that a terminal voltage of the fuel cell is equal to or higher than an open circuit voltage of the fuel cell.

Abstract: A solid oxide fuel cell including unit cells, including: a pair of interconnectors for electrically connecting the unit cells; a membrane-electrode assembly including an electrolyte membrane and a pair of electrode layers disposed with the electrolyte membrane therebetween; a pair of current collectors disposed between the electrode layers and the interconnectors so as to be in contact with the pair of electrode layers and the pair of interconnectors, respectively, and electrically connecting the pair of electrode layers and the pair of interconnectors; and elastic bodies biasing at least one current collector of the pair of current collectors toward a corresponding electrode layer and made of austenitic stainless steel.

Abstract: The fuel cell of the present disclosure includes: a fuel single cell comprising a fuel electrode, an air electrode, and an electrolyte disposed between the electrodes; a separator for separating a fuel gas flowing through the fuel electrode and air flowing through the air electrode; and a sealing portion for hermetically bonding between the separator and the electrolyte, wherein the sealing portion is constituted of a glass composition containing at least two of metallic or metalloid elements contained in the electrolyte and at least two of metallic or metalloid elements contained in the separator; the electrolyte includes a proton conductor; and the proton conductor is represented by a compositional formula: BaZr1-xMxO3, where 0.05?x?0.5; and M is at least one selected from the group consisting of Sc, In, Lu, Yb, Tm, Er, Y, Ho, Dy, and/or Gd.

Abstract: A cell including: a pair of interconnectors for electrically connecting unit cells; a membrane-electrode assembly disposed between the interconnectors; a pair of current collectors, each of which includes an abutting surface abutting against a corresponding one of the electrode layers and a first base material surface being in contact with a corresponding one of the interconnectors and electrically connecting the corresponding of the electrode layers and the corresponding one of the interconnectors; and elastic bodies biasing the abutting surface of at least one current collector toward a corresponding one of the electrode layers. The elastic bodies includes: a second base material surface being in contact with the first base material surface; and an elastic body protruding portion supporting the abutting surface and protruding from the second base material surface toward the corresponding one of the electrode layers to bias the abutting surface toward the corresponding one of the electrode layers.

Abstract: A fuel cell system includes: a fuel cell stack including a plurality of cells, each of which has a fuel electrode, an air electrode, and an electrolyte, and performs a power generation by a reaction between a fuel gas and air; a fuel supplier supplying the fuel gas to the fuel electrode; an air supplier supplying the air to the air electrode; a voltage detector detecting the voltage of the fuel cell stack; and a controller stopping the supplying of the fuel gas by the fuel supplier and the supplying of the air by the air supplier when the voltage of the fuel cell stack detected by the voltage detector is decreased to be lower than a threshold voltage after the power generation of the fuel cell stack is stopped.

Abstract: A fuel cell system according to the present disclosure includes: a solid oxide fuel cell that produces electricity from an electrochemical reaction by using a fuel and air and that includes a membrane electrode assembly including a proton-conductive electrolyte membrane, a cathode disposed on a first main surface of the electrolyte membrane, and an anode disposed on a second main surface of the electrolyte membrane; and a controller. In the operation stop process for stopping operation of the fuel cell system, the controller is configured to control supply of the fuel at a higher flow rate than the flow rate of the fuel consumed in the solid oxide fuel cell in an open circuit state.

Abstract: The electrochemical apparatus of the present disclosure includes a first stack that includes an oxide ion conductor as an electrolyte and decomposes water vapor to generate hydrogen and oxygen, a second stack that includes a proton conductor as an electrolyte and separates the hydrogen generated in the first stack from a gas mixture of the hydrogen and the water vapor that has not been decomposed in the first stack, and a heat insulation material that covers the first stack and the second stack.

Abstract: An electrochemical cell of the present disclosure includes a first cell and a second cell. The first cell includes a first electrolyte layer containing an oxide ion conductor. The second cell includes a second electrolyte layer containing a proton conductor, and the second cell is disposed to face the first cell.

Abstract: An electrochemical cell includes a first electrolyte layer containing an oxide-ion conductor, a second electrolyte layer containing a proton conductor, a first electrode which is disposed between the first electrolyte layer and the second electrolyte layer and in contact with a first principal surface of the first electrolyte layer and a first principal surface of the second electrolyte layer and into which a gas flows, a second electrode which is provided on a second principal surface of the first electrolyte layer and which generates oxygen, and a third electrode which is provided on a second principal surface of the second electrolyte layer and which generates hydrogen.

Abstract: A membrane electrode assembly according to the present disclosure includes an electrolyte membrane containing a proton conductive oxide and an electrode containing a lanthanum strontium cobalt iron composite oxide located on the electrolyte membrane, wherein, in the electrode, the ratio of the number of moles of cobalt to the sum of the number of moles of cobalt and the number of moles of iron is 0.35 or more and 0.6 or less.

Abstract: A membrane electrode assembly according to the present disclosure includes an electrode, an electrolyte layer bonded to the electrode and containing an electrolyte having proton conductivity, a metal frame, and a bonding layer disposed between a peripheral part of the electrolyte layer and the metal frame and held in contact with each of the electrolyte layer and the metal frame, wherein the bonding layer has a thickness of greater than or equal to 0.50 mm.

Abstract: A membrane electrode assembly according to the present disclosure includes an electrolyte membrane containing a solid electrolyte and a first electrode bonded to the electrolyte membrane, wherein the solid electrolyte is a compound represented by the composition formula (1): BaZr1-xMxO3-?, M in the composition formula (1) is at least one element selected from the group consisting of Sc, Er, Ho, Dy, Gd, Y, In, Tm, Yb, and Lu, and 0<x<1 and 0<?<0.5 are satisfied, and the first electrode contains a lanthanum strontium cobalt iron palladium composite oxide.

Abstract: A fuel cell system includes a fuel cell stack constituted by cells, each of the cells includes a fuel electrode, an air electrode, and an electrolyte, and generate electric power through a reaction of a fuel gas and air, a casing that houses the fuel cell stack, a temperature detector that detects a first temperature, the first temperature is a temperature of the fuel cell stack or inside the casing, and a controller. The controller controls based on the first temperature so as to allow an operation at a first predetermined temperature. The controller controls such that the first temperature reaches a temperature higher than or equal to a second predetermined temperature for a predetermined time. The second predetermined temperature is a temperature at which 475° C. embrittlement that occurs on stainless steel is eliminated. The first predetermined temperature is lower than the second predetermined temperature.

Abstract: A membrane electrode assembly according to the present disclosure is a membrane electrode assembly including: a solid electrolyte membrane containing an electrolyte material; and an electrode in contact with a reactant gas, wherein the electrode includes a structural support including a ceramic member, and a pore extending from a boundary surface in contact with the reactant gas toward the solid electrolyte membrane in the structural support and filled with a filler having at least one selected from the group consisting of hydrogen oxidation activity, oxygen reduction activity, proton reduction activity, steam decomposition activity, and oxide ion oxidation activity.

Abstract: The fuel cell of the present disclosure includes: a unit cell including: a fuel electrode, an air electrode and electrolyte disposed between the fuel electrode and the air electrodes; a separator for separating a fuel gas flowing though the fuel electrode and air flowing through the air electrode; and a sealing constituted of a glass composition for bonding the separator and the electrolyte, and at least a surface region of the sealing portion exposed to the fuel gas and the air does not contain Ba.