# US 2021/0280889 A1 · Redox flow battery > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2021/0280889 A1 - Document ID: US20210280889A1 - Status: Published application - Kind: A1 - Application number: 17/327,843 - Filed: 2021-05-24 - Published: 2021-09-09 - Earliest claimed: 2018-12-28 - Assignees: Panasonic Intellectual Property Management Co., Ltd. - Applicants: Panasonic Intellectual Property Management Co., Ltd. - Inventors: YU OTSUKA; SHUJI ITO; YUKA OKADA - Web page: https://patentgrep.com/patent/US20210280889A1 ## CPC - H01M 8/188: {by recharging of redox couples containing fluids; Redox flow type batteries} - H01M 8/02: Details (electrodes H01M4/86 - H01M4/98) - H01M 8/04186: of liquid-charged or electrolyte-charged reactants - H01M 8/04283: {Supply means of electrolyte to or in matrix-fuel cells} - H01M 2300/0017: Non-aqueous electrolytes - H01M 2300/0028: characterised by the solvent - Y02E 60/50: Fuel cells - H01M: PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY - Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION ## Abstract A redox flow battery includes a first nonaqueous liquid that contains at least one first electrode mediator; a first electrode at least in part in contact with the first nonaqueous liquid; a second nonaqueous liquid; a second electrode that is a counter electrode with respect to the first electrode and is at least in part in contact with the second nonaqueous liquid; and a separator that has at least one pore and separates the first and second nonaqueous liquids from each other. The at least one pore has an inner surface modified with a functional group that contains a hydrocarbon group. ## Claims ### Claim 1 A redox flow battery comprising: a first nonaqueous liquid that contains at least one first electrode mediator; a first electrode at least in part in contact with the first nonaqueous liquid; a second nonaqueous liquid; a second electrode that is a counter electrode with respect to the first electrode and is at least in part in contact with the second nonaqueous liquid; and a separator that has at least one pore and separates the first and second nonaqueous liquids from each other, wherein the at least one pore has an inner surface modified with a functional group that contains a hydrocarbon group. ### Claim 2 (depends on 1) The redox flow battery according to claim 1, wherein: the first nonaqueous liquid contains a first nonaqueous solvent and metal ions; the at least one pore includes a plurality of pores; and the plurality of pores have an average diameter larger than a size of each of the metal ions and smaller than a size of an aggregate containing molecules of the first electrode mediator solvated with the first nonaqueous solvent. ### Claim 3 (depends on 2) The redox flow battery according to claim 2, wherein the average diameter of the plurality of pores is larger than or equal to 0.5 nm and is smaller than or equal to 10 nm. ### Claim 4 (depends on 3) The redox flow battery according to claim 3, wherein the average diameter of the plurality of pores is larger than or equal to 3.0 nm and is smaller than or equal to 5.0 nm. ### Claim 5 (depends on 1) The redox flow battery according to claim 1, wherein the separator contains at least one inorganic material. ### Claim 6 (depends on 5) The redox flow battery according to claim 5, wherein the inorganic material contains silica-based glass. ### Claim 7 (depends on 1) The redox flow battery according to claim 1, wherein the hydrocarbon group has more than or equal to three and less than or equal to ten carbon atoms. ### Claim 8 (depends on 1) The redox flow battery according to claim 1, wherein the functional group contains a Si atom and modifies the inner surface of the at least one pore with a Si—O bond. ### Claim 9 (depends on 1) The redox flow battery according to claim 1, further comprising a first active material at least in part in contact with the first nonaqueous liquid, wherein: the first nonaqueous liquid contains metal ions; the first electrode mediator is at least one aromatic compound; the metal ions are lithium ions; the first nonaqueous liquid is capable of dissolving lithium; the first active material is a substance having a property to store and release lithium; and the first nonaqueous liquid has an electrical potential of smaller than or equal to 0.5 V vs. Li+/Li. ### Claim 10 (depends on 9) The redox flow battery according to claim 9, wherein the at least one aromatic compound includes at least one selected from the group consisting of biphenyl, phenanthrene, trans-stilbene, cis-stilbene, triphenylene, o-terphenyl, m-terphenyl, p-terphenyl, anthracene, benzophenone, acetophenone, butyrophenone, valerophenone, acenaphthene, acenaphthylene, fluoranthene, and benzil. ### Claim 11 (depends on 1) The redox flow battery according to claim 1, further comprising a second active material at least in part in contact with the second nonaqueous liquid, wherein: the second nonaqueous liquid contains at least one second electrode mediator; and the at least one second electrode mediator includes at least one selected from the group consisting of tetrathiafulvalene, triphenylamine, and derivatives thereof. ### Claim 12 (depends on 1) The redox flow battery according to claim 1, wherein each of the first and second nonaqueous liquids contains a compound that has at least one selected from the group consisting of a carbonate group and an ether group. ### Claim 13 (depends on 12) The redox flow battery according to claim 12, wherein each of the first and second nonaqueous liquids contains at least one selected from the group consisting of propylene carbonate, ethylene carbonate, dimethyl carbonate, ethyl methyl carbonate, and diethyl carbonate. ### Claim 14 (depends on 12) The redox flow battery according to claim 12, wherein each of the first and second nonaqueous liquids contains at least one selected from the group consisting of dimethoxyethane, diethoxyethane, dibutoxyethane, diglyme, triglyme, tetraglyme, polyethylene glycol dialkyl ethers, tetrahydrofuran, 2-methyltetrahydrofuran, 2,5-dimethyltetrahydrofuran, 1,3-dioxolane, and 4-methyl-1,3-dioxolane.