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: An electrochemical device includes an electrolyte membrane, an anode disposed on a first main surface of the electrolyte membrane, a cathode disposed on a second main surface of the electrolyte membrane, an anode separator disposed on the anode, and a cathode separator disposed on the cathode. At least one of the anode separator or the cathode separator includes a metal substrate sheet and a conductive layer disposed on the metal substrate sheet and containing a metal oxide and a metal hydroxide.

Abstract: A compressor includes at least one cell that includes an electrolyte membrane, an anode located on one main surface of the electrolyte membrane, and a cathode located on the other main surface of the electrolyte membrane; a metallic anode separator located on the anode; a cathode separator located on the cathode; and a voltage application unit for applying a voltage between the anode and the cathode, wherein the compressor causes, by using the voltage applier to apply a voltage, a proton extracted from an anode fluid supplied to the anode to move to the cathode and generates compressed hydrogen, and the compressor includes a controller for causing the voltage application unit to apply the voltage such that a voltage applied per unit cell is lower than a corrosion potential of the metallic anode separator.

Abstract: A hydrogen system includes a compressor that causes, by applying a voltage across an anode and a cathode with an interposed electrolyte membrane therebetween, hydrogen in a hydrogen-containing gas supplied to the anode to move to the cathode and produces compressed hydrogen; a pressure regulator that regulates pressure at least at the anode; and a controller that controls the pressure regulator to make the pressure at the anode higher than pressure at the cathode with the hydrogen-containing gas prevented from flowing out of the anode in a stop.

Abstract: A hydrogen system includes: a compressor including at least one cell that includes an electrolyte membrane, an anode catalyst layer provided on one principal surface of the electrolyte membrane, a cathode catalyst layer provided on another principal surface of the electrolyte membrane, an anode gas diffusion layer provided on the anode catalyst layer and including a porous sheet containing a metal, and a cathode gas diffusion layer provided on the cathode catalyst layer, and a voltage applicator that apples a voltage between the anode catalyst layer and the cathode catalyst layer, wherein the compressor that generates compressed hydrogen by causing the voltage applicator to apply the voltage to move hydrogen in hydrogen-containing gas supplied to an anode to the cathode via the electrolyte membrane; and a controller that causes the voltage applicator to apply the voltage after shutdown or at startup.

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 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: 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 device includes: an electrolyte membrane; an anode disposed on a first main surface of the electrolyte membrane; a cathode disposed on a second main surface of the electrolyte membrane; an anode separator disposed on the anode; and a cathode separator disposed on the cathode and including a first conductive layer on a surface adjacent to the cathode. The cathode includes a cathode gas diffusion layer. The cathode separator has a recess for storing the cathode gas diffusion layer. The first conductive layer is disposed only on a bottom surface of the recess.

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 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 hydrogen system includes a compressor that causes hydrogen in hydrogen-containing gas supplied to an anode to move to a cathode and produces compressed hydrogen by applying a voltage across the anode and the cathode disposed with an electrolyte membrane interposed therebetween; an anode gas supply channel through which the hydrogen-containing gas flows; a recycle channel through which anode off-gas flows; a drainage channel provided at a position of the recycle channel or anode gas supply channel on a downstream side relative to a position where the recycle channel merges and draining liquid water out of the recycle channel or anode gas supply channel; a pump provided in the recycle channel or the anode gas supply channel on the downstream side relative to the position; and a controller causing the pump to operate in a state where the applied voltage has been decreased when operation of the compressor is stopped.

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 SOFC system includes: a fuel cell stack; a reformer; an air supplier: a combustor; and a controller. In a stop control of the above system, the controller calculates an average of ratios of the air to the raw material supplied to the reformer as a first average, in a case in which a molar fraction of a hydrogen component in the anode off-gas is higher than a molar fraction of a raw material component in the anode off-gas, and calculates the average of the ratios of the air to the raw material supplied to the reformer as a second average, in a case in which the molar fraction of the hydrogen component in the anode off-gas is lower than the molar fraction of the raw material component in the anode off-gas. The controller controls the air supplier so that the first average is higher than the second average.

Abstract: An electrochemical device includes an electrolyte membrane, an anode disposed on a first main surface of the electrolyte membrane, a cathode disposed on a second main surface of the electrolyte membrane, an anode separator disposed on the anode, and a cathode separator disposed on the cathode. At least one of the anode separator or the cathode separator includes a metal substrate sheet and a conductive layer disposed on the metal substrate sheet and containing a metal oxide and a metal hydroxide.

Abstract: A fuel cell system includes: a fuel cell; a reformer to generate a hydrogen-containing gas; an electric power generation raw material supply unit; a reforming material supply unit configured to supply at least one of reforming water and reforming air, to the reformer; an oxidizing gas supply unit to supply an oxidizing gas to a cathode of the fuel cell; a combustor to ignite an exhaust gas discharged from the fuel cell; and a controller. In an operation stop process of the fuel cell system, the controller causes the oxidizing gas supply unit to supply the oxidizing gas, causes the electric power generation raw material supply unit and the reforming material supply unit to intermittently supply the electric power generation raw material and at least one of the water and the air to the reformer, and causes the ignitor to perform an ignition operation.

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.

Abstract: A fuel cell system includes: a fuel cell; a reformer to generate a hydrogen-containing gas; an electric power generation raw material supply unit; a reforming material supply unit configured to supply at least one of reforming water and reforming air, to the reformer; an oxidizing gas supply unit to supply an oxidizing gas to a cathode of the fuel cell; a combustor to ignite an exhaust gas discharged from the fuel cell; and a controller. In an operation stop process of the fuel cell system, the controller causes the oxidizing gas supply unit to supply the oxidizing gas, causes the electric power generation raw material supply unit and the reforming material supply unit to intermittently supply the electric power generation raw material and at least one of the water and the air to the reformer, and causes the ignitor to perform an ignition operation.