# US 12,224,436 B2 · Cathode active material for lithium secondary battery and lithium secondary battery including same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,224,436 B2 - Document ID: US12224436B2 - Status: Granted - Kind: B2 - Application number: 16/962,635 - Filed: 2019-01-29 - Published: 2020-11-05 - Granted: 2025-02-11 - Earliest claimed: 2018-01-29 - Assignees: Samsung SDI Co., Ltd. - Applicants: Samsung SDI Co., Ltd. - Inventors: Jongmin Kim; Soohyeon Kim; Jinhwa Kim; Pilsang Yun - Web page: https://patentgrep.com/patent/US12224436B2 ## CPC - H01M 4/525: of mixed oxides or hydroxides containing iron, cobalt or nickel for inserting or intercalating light metals, e.g. LiNiO2, LiCoO2 or LiCoOxFy - H01M 10/052: Li-accumulators - H01M 4/505: of mixed oxides or hydroxides containing manganese for inserting or intercalating light metals, e.g. LiMn2O4 or LiMn2OxFy - 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} - 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 Disclosed are a cathode active material for a lithium secondary battery and a lithium secondary battery including the same. The cathode active material includes a secondary particle in which a plurality of primary particles are agglomerated, wherein the secondary particle has a predetermined arrangement structure in which (003) surface of primary particles are aligned to be in a vertical direction with respect to a tangent line at a point (P) at which the (003) surface of the primary particles meet a surface of the secondary particle. ## Claims ### Claim 1 A cathode active material for a lithium secondary battery, comprising: a secondary particle in which a plurality of primary particles are agglomerated, the secondary particle comprising a core and a surface portion, and having a predetermined arrangement structure in which (003) surfaces of primary particles of the plurality of primary particles are aligned to be in a vertical direction with respect to respective tangent lines at points (P) at which the (003) surfaces of the primary particles meet a surface of the secondary particle; and wherein the vertical direction in which the (003) surfaces of the primary particles are aligned is 90°±20° with respect to the respective tangent lines; wherein a pore volume fraction of micropores of less than or equal to 10 nm of the secondary particle is greater than or equal to 10% of a total pore volume, and the micropores of less than or equal to 10 nm are at the surface portion of the secondary particle; and wherein the secondary particle has an average pore size that decreases sequentially from an average pore size of the core to an average pore size of the surface portion. ### Claim 2 (depends on 1) The cathode active material of claim 1, wherein about 50% or more of the plurality of primary particles are arranged to be in the vertical direction with respect to their respective tangent lines at the points (P) at which (003) surfaces of the about 50% or more of the plurality of primary particles meet the surface of the secondary particle. ### Claim 3 (depends on 1) The cathode active material of claim 1, wherein an average length of the primary particles in a c-axis direction is in a range of 100 nm to 200 nm. ### Claim 4 (depends on 1) The cathode active material of claim 1, wherein a ratio of a length of a long side of one of the (003) surfaces and a length of a short side of the one of the (003) surfaces that is perpendicular to the long side is in a range of 2:1 to 10:1. ### Claim 5 (depends on 1) The cathode active material of claim 1, wherein the secondary particle has a radial array structure having one center or a multi-core radial array structure having a plurality of centers. ### Claim 6 (depends on 1) The cathode active material of claim 1, wherein the secondary particle has porosity that decreases sequentially from the core to the surface of the secondary particle. ### Claim 7 (depends on 1) A lithium secondary battery comprising: a cathode comprising the cathode active material of claim 1; an anode; and an electrolyte therebetween. ### Claim 8 (depends on 7) The lithium secondary battery of claim 7, wherein about 50% or more of the plurality of primary particles are arranged to be in the vertical direction with respect to their respective tangent lines at the points (P) at which (003) surfaces of the about 50% or more of the plurality of primary particles meet the surface of the secondary particle. ### Claim 9 (depends on 7) The lithium secondary battery of claim 7, wherein an average length of the primary particles in a c-axis direction is in a range of 100 nm to 200 nm. ### Claim 10 (depends on 7) The lithium secondary battery of claim 7, wherein a ratio of a length of a long side of one of the (003) surfaces and a length of a short side of the one of the (003) surfaces that is perpendicular to the long side is in a range of 2:1 to 10:1. ### Claim 11 (depends on 7) The lithium secondary battery of claim 7, wherein the secondary particle has a radial array structure having one center or a multi-core radial array structure having a plurality of centers. ### Claim 12 (depends on 7) The lithium secondary battery of claim 7, wherein the secondary particle has a pore size that decreases sequentially from the core to the surface of the secondary particle. ### Claim 13 (depends on 7) The lithium secondary battery of claim 7, wherein the secondary particle has porosity that decreases sequentially from the core to the surface of the secondary particle. ### Claim 14 (depends on 1) The cathode active material of claim 1, wherein a porosity of the core is 2% to 20%, and a porosity of the surface portion is 0.3% to 0.7%. ### Claim 15 (depends on 1) The cathode active material of claim 1, wherein the average pore size of the core is 150 nm to 1 μm, and the average pore size of the surface portion is less than 150 nm.