# US 12,191,478 B2 · Anode active material and preparation method thereof, and device using the anode active material > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,191,478 B2 - Document ID: US12191478B2 - Status: Granted - Kind: B2 - Application number: 17/274,810 - Filed: 2019-11-19 - Published: 2022-02-17 - Granted: 2025-01-07 - Earliest claimed: 2019-03-20 - Assignees: Ningde Amperex Technology Limited - Applicants: Ningde Amperex Technology Limited - Inventors: Zhihuan Chen; Daoyi Jiang; Hang Cui; Yuansen Xie - Web page: https://patentgrep.com/patent/US12191478B2 ## CPC - H01M 4/364: {as mixtures} - H01M 4/483: {for non-aqueous cells (H01M4/485 takes precedence)} - H01M 4/0404: {by coating on electrode collectors} - H01M 4/13: Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof - H01M 4/133: Electrodes based on carbonaceous material, e.g. graphite-intercalation compounds or CFx - H01M 4/134: Electrodes based on metals, Si or alloys - H01M 4/366: {as layered products} - H01M 4/386: {Silicon or alloys based on silicon} - H01M 4/48: of inorganic oxides or hydroxides - H01M 4/587: for inserting or intercalating light metals - H01M 4/622: {being polymers} - H01M 4/623: {fluorinated polymers} - H01M 4/625: {Carbon or graphite} - H01M 10/0525: Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries - H01M 2004/021: {Physical characteristics, e.g. porosity, surface area} - H01M 2004/027: {Negative electrodes} - 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 anode active material and a preparation method thereof, and a device using the anode active material. The anode active material provided by the present application includes anode active particles having silicon element, a first conductive material and a second conductive material, wherein the first conductive material and the second conductive material form a three-dimensional conductive network structure, at least a portion of the anode active particles are accommodated in the three-dimensional conductive network structure, and a ratio of the total surface area of the first conductive material to the total surface area of the anode active particles is less than 1000. The capacity retention rate and expansion ratio of the anode active material with progression of the cycle are significantly improved. ## Claims ### Claim 1 An anode active material, comprising anode active particles having silicon element, a first conductive material and a second conductive material, wherein the first conductive material and the second conductive material form a three-dimensional conductive network structure; at least a portion of the anode active particles are accommodated in the three-dimensional conductive network structure; and a ratio of a total surface area of the first conductive material to a total surface area of the anode active particles is less than about 1000, wherein the first conductive material has a length to diameter ratio of about 50 to about 3000 and a diameter of about 2 nm to about 30 nm; the second conductive material has a length to diameter ratio of about 20 to about 500 and a diameter of about 50 nm to about 500 nm; the anode active particles have an average diameter D50 of about 0.5 μm to about 30 μm, and an average length L50 of the second conductive material and the D50 of the anode active particles satisfy: (L50−D50)/D50≥1, the L50 and the D50 being both in μm; and the first conductive material comprises carbon nanotubes containing at least one polar group, and the second conductive material comprises carbon fibers. ### Claim 2 (depends on 1) The anode active material according to claim 1, wherein a mass of the first conductive material accounts for about 5% to about 30% of a mass of total conductive materials. ### Claim 3 (depends on 1) The anode active material according to claim 1, wherein a ratio of a total mass of the first conductive material and the second conductive material to a total mass of the anode active particles is about 1:100 to about 5:100. ### Claim 4 (depends on 1) The anode active material according to claim 1, wherein the carbon fibers comprise vapor grown carbon fibers VGCFs, carbon nanofibers or a combination of them. ### Claim 5 (depends on 1) The anode active material according to claim 1, wherein the first conductive material is bonded to a surface of the anode active particles by one or more covalent bonds. ### Claim 6 (depends on 1) The anode active material according to claim 1, wherein the anode active particles comprise a simple substance of silicon, a compound of silicon, an alloy of silicon or any combination of the above. ### Claim 7 (depends on 6) The anode active material according to claim 6, wherein the anode active particles comprise SiOx, x=0.5 to 1.5, and the SiOx comprises crystalline SiOx, amorphous SiOx or a combination of them. ### Claim 8 (depends on 1) The anode active material according to claim 1, wherein at least a portion of the surface of the anode active particles is coated with an oxide. ### Claim 9 (depends on 1) The anode active material according to claim 1, further comprising a third conductive material, wherein a mass of the third conductive material accounts for about 1% to about 20% of a mass of total conductive materials. ### Claim 10 (depends on 9) The anode active material according to claim 9, wherein the third conductive material comprises conductive carbon black, acetylene black, Ketjen black, conductive graphite, graphene or any combination of the above. ### Claim 11 (depends on 1) The anode active material according to claim 1, wherein the anode active particles further comprise a carbon material. ### Claim 12 (depends on 11) The anode active material according to claim 11, wherein the carbon material comprises artificial graphite, natural graphite or a combination thereof, the artificial graphite or the natural graphite comprising mesocarbon microbeads, soft carbon, hard carbon or any combination of the above. ### Claim 13 (depends on 1) The anode active material according to claim 1, further comprising a binder. ### Claim 14 An anode, comprising a current collector and anode active material, wherein the anode active material is coated on at least one surface of the current collector, wherein the anode active material comprising anode active particles having silicon element, a first conductive material and a second conductive material, wherein the first conductive material and the second conductive material form a three-dimensional conductive network structure; at least a portion of the anode active particles are accommodated in the three-dimensional conductive network structure; and a ratio of a total surface area of the first conductive material to a total surface area of the anode active particles is less than about 1000, wherein the first conductive material has a length to diameter ratio of about 50 to about 3000 and a diameter of about 2 nm to about 30 nm; the second conductive material has a length to diameter ratio of about 20 to about 500 and a diameter of about 50 nm to about 500 nm: the anode active particles have an average diameter D50 of about 0.5 μm to about 30 μm, and an average length L50 of the second conductive material and the D50 of the anode active particles satisfy: (L50−D50)/D50≥1, the L50 and the D50 being both in μm; and the first conductive material comprises carbon nanotubes containing at least one polar group, and the second conductive material comprises carbon fibers. ### Claim 15 (depends on 14) The anode according to claim 14, wherein the anode has a thickness of about 50 μm to about 200 μm, a single to sided compacted density of about 1.2 g/cm3 to about 2.0 g/cm3 and a resistivity of about 0.001 Ω·cm to about 1000 Ω·cm. ### Claim 16 (depends on 14) The anode according to claim 14, wherein a peel strength between the anode active material and the current collector is greater than about 20 N/m. ### Claim 17 An electrochemical device, comprising: a cathode; an anode; a separator; and electrolyte, wherein the anode comprises anode active particles having silicon element, a first conductive material and a second conductive material, wherein the first conductive material and the second conductive material form a three-dimensional conductive network structure; at least a portion of the anode active particles are accommodated in the three-dimensional conductive network structure; and a ratio of a total surface area of the first conductive material to a total surface area of the anode active particles is less than about 1000, wherein the first conductive material has a length to diameter ratio of about 50 to about 3000 and a diameter of about 2 nm to about 30 nm; the second conductive material has a length to diameter ratio of about 20 to about 500 and a diameter of about 50 nm to about 500 nm; the anode active particles have an average diameter D50 of about 0.5 μm to about 30 μm, and an average length L50 of the second conductive material and the D50 of the anode active particles satisfy: (L50−D50)/D50≥1, the L50 and the D50 being both in μm; and the first conductive material comprises carbon nanotubes containing at least one polar group, and the second conductive material comprises carbon fibers.