# US 2021/0242535 A1 · Electrochemical device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2021/0242535 A1 - Document ID: US20210242535A1 - Status: Published application - Kind: A1 - Application number: 16/967,617 - Filed: 2020-03-27 - Published: 2021-08-05 - Earliest claimed: 2019-03-29 - Assignees: Ningde Amperex Technology Limited - Applicants: Ningde Amperex Technology Limited - Inventors: Yibo ZHANG; Xiang LI; Bin WANG; Ying SHAO - Web page: https://patentgrep.com/patent/US20210242535A1 ## CPC - H01M 50/44: Fibrous material - H01M 10/0525: Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries - H01M 50/414: Synthetic resins, e.g. thermoplastics or thermosetting resins - H01M 50/426: Fluorocarbon polymers - H01M 50/434: Ceramics - H01M 50/454: comprising a non-fibrous layer and a fibrous layer superimposed on one another - H01M 50/457: comprising three or more layers - H01M 50/46: Separators, membranes or diaphragms characterised by their combination with electrodes - H01M 50/491: Porosity - Y02E 60/10: Energy storage using batteries - 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 The present application relates to an electrochemical device. The electrochemical device includes: at least one electrode, the at least one electrode having a first surface; and a fiber coating layer, the fiber coating layer including a fiber and being disposed on the first surface. The electrochemical device has the advantages of high energy density, strong liquid retention ability, good drop resistance, good chemical stability and the like since its fiber coating layer has small thickness, high porosity and stronger interfacial adhesion to the electrode. ## Claims ### Claim 1 An electrochemical device, comprising: at least one electrode having a first surface; and a fiber coating layer, the fiber coating layer comprising fibers and being disposed on the first surface. ### Claim 2 (depends on 1) The electrochemical device according to claim 1, wherein the adhesion of the fiber coating layer to the first surface is 2 N/m to 100 N/m. ### Claim 3 (depends on 1) The electrochemical device according to claim 1, wherein the fibers comprise a first fiber and a second fiber, a diameter of the first fiber being less than a diameter of the second fiber, and the first fiber being adjacent to the first surface. ### Claim 4 (depends on 3) The electrochemical device according to claim 3, wherein the first fiber has the diameter of 10 nm to 2 μm, and the second fiber has the diameter of 20 nm to 5 μm. ### Claim 5 (depends on 1) The electrochemical device according to claim 1, wherein the fiber coating layer comprises a first porous layer and a second porous layer; an average pore diameter of the first porous layer being less than an average pore diameter of the second porous layer; and the first porous layer being adjacent to the first surface. ### Claim 6 (depends on 5) The electrochemical device according to claim 5, wherein the first porous layer has the average pore diameter of 20 nm to 5 μm; and the second porous layer has the average pore diameter of greater than 20 nm and less than or equal to 10 μm. ### Claim 7 (depends on 5) The electrochemical device according to claim 5, further comprising a third porous layer is provided between the first porous layer and the second porous layer; an average pore diameter of the third porous layer being between the average pore diameters of the first porous layer and the second porous layer. ### Claim 8 (depends on 1) The electrochemical device according to claim 1, wherein a material of the fiber is at least one selected from the group consisting of polyvinylidene fluoride, polyimide, polyamide, polyacrylonitrile, polyethylene glycol, polyoxyethylene, polyphenylene oxide, polypropylene carbonate, polymethyl methacrylate, polyethylene terephthalate, poly(ethylene oxide), a vinylidene fluoride-hexafluoropropylene copolymer, a vinylidene fluoride-trifluorochloroethylene copolymer and derivatives thereof. ### Claim 9 (depends on 1) The electrochemical device according to claim 1, wherein the fiber coating layer has a porosity of 30% to 95% and a thickness of 1 μm to 20 μm. ### Claim 10 (depends on 1) The electrochemical device according to claim 1, wherein the fiber coating layer further comprises inorganic particles. ### Claim 11 (depends on 1) The electrochemical device according to claim 1, wherein a surface of the fiber coating layer is provided with an inorganic porous layer, the inorganic porous layer comprising inorganic particles. ### Claim 12 (depends on 10) The electrochemical device according to claim 10, wherein the inorganic particles are at least one selected from the group consisting of: (a) inorganic particles having a dielectric constant of 5 or more; (b) inorganic particles having piezoelectricity; and (c) inorganic particles having lithium ion conductivity. ### Claim 13 (depends on 12) The electrochemical device according to claim 12, wherein the inorganic particles are the inorganic particles having the dielectric constant of 5 or more; the inorganic particles comprise at least one selected from the group consisting of BaO, SiO2, SrTiO3, SnO2, CeO2, MgO, NiO, CaO, ZnO, ZrO2, Y2O3, Al2O3, TiO2, boehmite, magnesium hydroxide, aluminum hydroxide, and SiC. ### Claim 14 (depends on 12) The electrochemical device according to claim 12, wherein the inorganic particles are the inorganic particles having piezoelectricity; the inorganic particles comprise at least one selected from the group consisting of BaTiO3, Pb(Zr,Ti)O3, Pb1-xLaxZr1-yTiyO3 (0