# US 2021/0242489 A1 · Negative electrode for lithium-ion secondary battery, and lithium-ion secondary battery > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2021/0242489 A1 - Document ID: US20210242489A1 - Status: Published application - Kind: A1 - Application number: 17/232,334 - Filed: 2021-04-16 - Published: 2021-08-05 - Earliest claimed: 2018-10-17 - Assignees: Murata Manufacturing Co., Ltd. - Applicants: Murata Manufacturing Co., Ltd. - Inventors: Yoshihide NAGATA; Naoki KOSHITANI - Web page: https://patentgrep.com/patent/US20210242489A1 ## CPC - H01M 10/0525: Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries - 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 4/386: {Silicon or alloys based on silicon} - H01M 4/583: Carbonaceous material, e.g. graphite-intercalation compounds or CFx - H01M 4/587: for inserting or intercalating light metals - H01M 10/0565: Polymeric materials, e.g. gel-type or solid-type - H01M 2004/021: {Physical characteristics, e.g. porosity, surface area} - H01M 2004/027: {Negative electrodes} - H01M 2300/0082: Organic polymers - H01M 2300/0085: Immobilising or gelification of electrolyte - 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 A lithium-ion secondary battery includes a positive electrode, a negative electrode, and an electrolytic solution. The negative electrode includes a negative electrode active material layer having fine pores. The negative electrode active material layer includes first negative electrode active material particles and second negative electrode active material particles. The first negative electrode active material particles each include carbon-containing particles and silicon-containing particles in an ion-conductive material. The second negative electrode active material particles each include a carbon-containing material. A pore size that represents a peak of a volume fraction of an amount of mercury intruded into the fine pores is from 1 μm to 3 μm. ## Claims ### Claim 1 A lithium-ion secondary battery comprising: a positive electrode; a negative electrode including a negative electrode active material layer having fine pores; and an electrolytic solution, wherein the negative electrode active material layer includes first negative electrode active material particles and second negative electrode active material particles, wherein the first negative electrode active material particles each include carbon-containing particles and silicon-containing particles in an ion-conductive material, and the second negative electrode active material particles each include a carbon-containing material, and wherein a pore size that represents a peak of a volume fraction of an amount of mercury intruded into the fine pores is from 1 micrometer to 3 micrometers. ### Claim 2 (depends on 1) The lithium-ion secondary battery according to claim 1, wherein the ion-conductive material includes at least one of an ion-conductive polymer compound or a solid electrolyte. ### Claim 3 (depends on 1) The lithium-ion secondary battery according to claim 1, wherein the ion-conductive material has ionic conductivity from 10−6 siemens per centimeter to 10−1 siemens per centimeter. ### Claim 4 (depends on 2) The lithium-ion secondary battery according to claim 2, wherein the ion-conductive material has ionic conductivity from 10−6 siemens per centimeter to 10−1 siemens per centimeter. ### Claim 5 (depends on 1) The lithium-ion secondary battery according to claim 1, wherein a proportion of a weight of the ion-conductive material to a weight of the first negative electrode active material particles is from 1.0 weight percent to 2.5 weight percent. ### Claim 6 (depends on 2) The lithium-ion secondary battery according to claim 2, wherein a proportion of a weight of the ion-conductive material to a weight of the first negative electrode active material particles is from 1.0 weight percent to 2.5 weight percent. ### Claim 7 (depends on 3) The lithium-ion secondary battery according to claim 3, wherein a proportion of a weight of the ion-conductive material to a weight of the first negative electrode active material particles is from 1.0 weight percent to 2.5 weight percent. ### Claim 8 (depends on 1) The lithium-ion secondary battery according to claim 1, wherein a proportion of a weight of the silicon-containing particles to a sum total of a weight of the carbon-containing particles and the weight of the silicon-containing particles is from 60.6 weight percent to 85.9 weight percent. ### Claim 9 (depends on 1) The lithium-ion secondary battery according to claim 1, wherein the first negative electrode active material particles have a first median diameter from 3.5 micrometers to 13.0 micrometers, and the second negative electrode active material particles have a second median diameter from 7.0 micrometers to 20.0 micrometers. ### Claim 10 (depends on 1) The lithium-ion secondary battery according to claim 1, wherein a proportion of a weight of the first negative electrode active material particles to a sum total of the weight of the first negative electrode active material particles and a weight of the second negative electrode active material particles is from 10.5 weight percent to 42.1 weight percent. ### Claim 11 A negative electrode for a lithium-ion secondary battery, the negative electrode comprising a negative electrode active material layer having fine pores, wherein the negative electrode active material layer includes first negative electrode active material particles and second negative electrode active material particles, the first negative electrode active material particles each include carbon-containing particles and silicon-containing particles in an ion-conductive material, the second negative electrode active material particles each include a carbon-containing material, and a pore size representing a peak of a volume fraction of an amount of mercury intruded into the fine pores is from 1 micrometer to 3 micrometers.