Abstract: An electrode of an embodiment includes: a power feeder layer including an electric conductive material, the power feeder layer including a porous structure including porosity of 40% or more and 60% or less; and a catalyst layer provided on the power feeder layer, the catalyst layer including a porous catalyst layer including a porous precious metal or sheet-like precious metal.

Abstract: An electrode for an electrochemical reaction device, includes: a substrate; and a stack provided on the substrate. The stack includes catalyst layers and gap layers, and each catalyst layer and each gap layer are alternately stacked. One of the gap layers has a first region and a second region, the first region having a first thickness, the second region having a first gap, and the first gap having a second thickness, and the second thickness is 3 times or more and 10 times or less the first thickness.

Abstract: An electrode according to an embodiment includes a support, and a catalyst layer including a sheet layer and a gap layer stacked, alternately on the support. The catalyst layer includes noble oxide and non-noble oxide. 4 [wt %] or more and 8 [wt %] or less of metal elements included in the catalyst layer is non-noble metal. An average thickness of the gap layer is 6 [nm] or more and 50 [nm] or less.

Abstract: A membrane electrode assembly according to an embodiment includes a first diffusion layer; a second diffusion layer; an electrolyte membrane provided between the first diffusion layer and the second diffusion layer; a first catalyst layer provided between the first diffusion layer and the electrolyte membrane; and a second catalyst layer provided between the second diffusion layer and the electrolyte membrane, wherein the first diffusion layer includes a first surface facing the first catalyst layer, and the first surface includes a chamfered portion, and a second surface provided on an opposing side of the first surface, and the second surface includes a protrusion protruding from the side of the first surface toward the side of the second surface.

Abstract: A membrane electrode assembly of an embodiment includes: a first electrode including a first diffusion layer, and a first catalyst layer; a second electrode for generating hydrogen, the second electrode including a second diffusion layer, a second catalyst layer including a porous catalyst layer including a porous precious metal or sheet-like precious metal, and a hydrophobic moisture management layer provided between the second catalyst layer and the second diffusion layer, the hydrophobic moisture management layer including carbon particles and carbon fibers, a weight of the carbon fibers being between 1 wt % and 20 wt % of a weight of the second diffusion layer; and an electrolyte membrane provided between the first electrode and the second electrode, the first catalyst layer being provided between the first diffusion layer and the electrolyte membrane, and the second catalyst layer being provided between the second diffusion layer and the electrolyte membrane.

Abstract: A water electrolysis device includes: an anode; a cathode; an electrolyte membrane between the anode and the cathode; a first circulation flow path connecting a anode supply flow path and a anode discharge flow path; a second circulation flow path connected in parallel with the first circulation flow path; an ion filter in a middle of the second circulation flow path and to remove metal ions in the anode solution; a metal supply source to supply metal ions into the anode solution; a first valve in a middle of the first circulation flow path; a second valve in a middle of the second circulation flow path; a third valve in a middle of the metal supply flow path; a sensor to measure concentration of metal ions in the anode solution; and a controller to control opening and closing of each valve, according to the measured concentration of the metal ions.

Abstract: An electrode for electrochemical reaction device of an embodiment includes: a substrate; and a catalyst lamination provided on the substrate, and having a plurality of catalyst layers, and void layers respectively arranged between the plurality of catalyst layers adjacent to each other. The plurality of catalyst layers include a first catalyst layer arranged at a position close to the substrate and having a first thickness, and a second catalyst layer arranged at a position separated from the substrate and having a second thickness that is smaller than the first thickness.

Abstract: A support according to an embodiment includes fibers. A first arithmetic mean roughness of the fibers observed from in-plane direction of the support is 7 [?m] or more and 40 [?m] or less. A first sampling length of the first arithmetic mean roughness is one fifth of an average diameter of the fibers observed from the in-plane direction of the support.

Abstract: An electrode according to an embodiment includes a support, an intermediate layer including carbon particles and resin on the support, and a catalyst layer on the intermediate layer. A thickness of the intermediate layer is 70 [?m] or more and 300 [?m] or less.

Abstract: An electrode according to an embodiment includes a support and a catalyst layer including a sheet layer and a gap layer stacked alternately. Cracks or/and holes exist in the catalyst layer.

Abstract: A manufacturing method for a electrolyte membrane including noble metal particles according to an embodiment includes a step of impregnating cationic noble metal complex ions with a first region of a surface of a cation exchange membrane by spraying solution containing the cationic noble metal complex ions on the cation exchange membrane and drying the sprayed member, and a step of applying a reducing treatment to the cation exchange membrane impregnated with the cationic noble metal complex ions.

Abstract: A membrane electrode assembly according to an embodiment includes a first electrode, a second electrode, an electrolyte membrane provided between the first electrode and the second electrode and a first seal provided on a peripheral portion of the first electrode, having a first opening, housing the first electrode in the first opening, and being contact with the electrolyte membrane or the first seal and a second seal provided on a peripheral portion of the second electrode, having a second opening, housing the second electrode in the second opening, and being contact with the electrolyte membrane.

Abstract: A laminated catalyst according to an embodiment includes an oxide layer, a first catalyst layer on the oxide layer and a second catalyst layer on the first catalyst layer. The oxide layer is a layer of oxide including one or more non-noble metals as a main component. The first catalyst layer includes an oxide of noble metal including Ir and/or Ru as a main component. The second catalyst layer includes an oxide of noble metal including Ir and/or Ru as a main component. The first catalyst layer is denser than the second catalyst layer.

Abstract: An electrochemical device of an embodiment includes: an electrochemical cell including a first electrode having a first flow path, a second electrode having a second flow path, and a separating membrane sandwiched between the first electrode and the second electrode; a gas-liquid separation tank which is connected to the first flow path of the first electrode and to which a product produced at the first electrode and water permeating from the second electrode to the first electrode are sent at an operation time; and a water sealing pipe which is connected to a liquid portion of the gas-liquid separation tank, and to send water in the gas-liquid separation tank to the first flow path of the first electrode at a stop time.

Abstract: In a diagnosis method of an embodiment, a battery, which includes, as electrode active materials, a first electrode active material whose impedance has a first natural frequency and a second natural frequency lower than the first natural frequency and a second electrode active material whose impedance has a third natural frequency with a magnitude between the first natural frequency and the second natural frequency, is diagnosed. In the method, an impedance of the battery is measured at each of a plurality of measurement target frequencies by setting, as a measurement range, a first measurement range including the first natural frequency and not including the second and third natural frequencies, and a second measurement range including the second natural frequency and not including the first and third natural frequencies.

Abstract: An electrochemical reaction device of an embodiment includes: an electrochemical reaction cell 1 that includes: a first electrode having a first flow path, a second electrode having a second flow path, and a separating membrane sandwiched between the first electrode and the second electrode; a liquid tank that contains a liquid to be treated supplied to the second flow path of the second electrode; a first pipe that connects an inlet of the second flow path and the liquid tank; a second pipe that connects an outlet of the second flow path and the liquid tank; and a backflow suppression mechanism that is provided in the second pipe to prevent backflow of the liquid to be treated flowing in the second pipe or reduce a backflow speed.

Abstract: In an embodiment, an aging determination method of a battery as a target of determination is provided. With regard to a target electrode which is at least one of a positive electrode and a negative electrode of the battery, the method estimates a correction coefficient to correct a difference between lithium concentration distributions in the target electrode at a time of charging with a first electric current and at a time of charging with a second electric current greater than the first electric current based on a difference between electric potentials of a target electrode at the time of charging with the first electric current and at the time of charging with the second electric current, and an impedance of the target electrode at the time of charging with the second electric current.

Abstract: In an embodiment, an aging determination method of a battery as a target of determination is provided. With regard to a target electrode which is at least one of a positive electrode and a negative electrode of the battery, the method estimates a correction coefficient to correct a difference between lithium concentration distributions in the target electrode at a time of charging with a first electric current and at a time of charging with a second electric current greater than the first electric current based on a difference between electric potentials of a target electrode at the time of charging with the first electric current and at the time of charging with the second electric current, and an impedance of the target electrode at the time of charging with the second electric current.

Abstract: A catalyst laminate includes a plurality of catalyst layers containing at least one of a noble metal and an oxide of the noble metal and at least one of a non-noble metal and an oxide of the non-noble metal, including: two or more first catalyst layers and two or more second catalyst layers. In an atomic percent of the noble metal obtained by using a line analysis by energy dispersive X-ray spectroscopy in a thickness direction of the catalyst laminate. The first catalyst layer is less than an average of a highest value and a lowest value of the atomic percent of the noble metal. The second catalyst layer has an atomic percent of the noble metal equal to or greater than the average of the highest value and the lowest value thereof. The second catalyst layer is present between the first catalyst layers.

Abstract: According to one embodiment, there is provided a composite. The composite includes active material particles of a titanium composite oxide or oxide of titanium, and a graphene structure including a carbon material. The carbon material has a graphene framework defining a graphene surface. The graphene structure is located in between the active material particles. The graphene structure has at least one side surface in contact with the active material particle. The side surface includes the carbon material whose graphene surface is slanted relative to the side surface.