# US 7,608,362 B2 · Cathode active material, method of preparing the same, and cathode and lithium battery containing the material > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,608,362 B2 - Document ID: US7608362B2 - Status: Granted - Kind: B2 - Application number: 11/355,381 - Filed: 2006-02-15 - Published: 2006-11-16 - Granted: 2009-10-27 - Earliest claimed: 2005-02-15 - Assignees: Samsung SDI Co., Ltd. - Inventors: Young-min Choi; Kyung-ho Kim; Gue-sung Kim - Web page: https://patentgrep.com/patent/US7608362B2 ## CPC - H01M 4/505: of mixed oxides or hydroxides containing manganese for inserting or intercalating light metals, e.g. LiMn2O4 or LiMn2OxFy - B82Y 30/00: Nanotechnology for materials or surface science, e.g. nanocomposites - H01M 4/131: Electrodes based on mixed oxides or hydroxides, or on mixtures of oxides or hydroxides, e.g. LiCoOx - H01M 4/364: {as mixtures} - 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 4/5825: {Oxygenated metallic salts or polyanionic structures, e.g. borates, phosphates, silicates, olivines} - H01M 4/02: Electrodes composed of, or comprising, active material - H01M 4/0435: {Rolling or calendering} - H01M 2004/021: {Physical characteristics, e.g. porosity, surface area} - H01M 2004/028: {Positive 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 - B82Y: SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES - Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION ## Abstract Composite cathode active materials having a large diameter active material and a small diameter active material are provided. The ratio of the average particle diameter of the large diameter active material to the average particle diameter of the small diameter active material ranges from about 6:1 to about 100:1. Mixing the large and small diameter active materials in a proper weight ratio improves packing density Additionally, including highly stable materials and highly conductive materials in the composite cathode active materials improves volume density, discharge capacity and high rate discharge capacity. ## Claims ### Claim 1 A composite cathode active material comprising: at least one large diameter active material selected from the group consisting of LiNi0.8Co0.1Mn0.1O2, LiNiO2, LiNi0.9Co0.1O2, LiNi0.8Co0.1Al0.1O2 and mixtures thereof; and at least one small diameter active material comprising a carbon-based material selected from the group consisting of graphite, hard carbon, carbon black, carbon fiber, carbon nanotubes (CNT) and mixtures thereof, wherein a ratio of an average particle diameter of the large diameter active material to an average particle diameter of the small diameter active material ranges from about 6:1 to about 100:1. ### Claim 2 (depends on 1) The composite cathode active material according to claim 1, wherein the ratio of the average particle diameter of the large diameter active material to the average particle diameter of the small diameter active material ranges from about 6:1 to about 20:1. ### Claim 3 (depends on 1) The composite cathode active material according to claim 1, wherein a weight ratio of the large diameter active material to the small diameter active material ranges from about 60:40 to about 90:10. ### Claim 4 (depends on 1) The composite cathode active material according to claim 1, wherein a weight ratio of the large diameter active material to the small diameter active material ranges from about 70:30 to about 80:20. ### Claim 5 (depends on 1) The composite cathode active material according to claim 1, wherein a mole ratio of the large diameter active material to the small diameter active material ranges from about 60/Mw1:40/Mw2 to about 90/Mw1:10/Mw2, wherein: Mw1 is a molecular weight of the large diameter active material, Mw2 is a molecular weight of the small diameter active material, and each of w1 and w2 is an integer other than 0. ### Claim 6 (depends on 1) The composite cathode active material according to claim 1, wherein a mole ratio of the large diameter active material to the small diameter active material ranges from about 70/Mw1:30/Mw2 to about 80/Mw1:20/Mw2, wherein: M1 is a molecular weight of the large diameter active material, M2 is a molecular weight of the small diameter active material, and each of w1 and w2 is an integer other than 0. ### Claim 7 (depends on 1) The composite cathode active material according to claim 1, wherein the average particle diameter of the large diameter active material ranges from about1 to about 25 μm. ### Claim 8 (depends on 1) The composite cathode active material according to claim 1, wherein the average particle diameter of the small diameter active material ranges from about 0.05 to about 5 μm. ### Claim 9 (depends on 1) A cathode comprising the composite cathode active material of claim 1. ### Claim 10 (depends on 9) A lithium battery comprising the cathode of claim 9. ### Claim 11 (depends on 1) The composite cathode active material of claim 1, wherein the at least one small diameter active material further comprises a material selected from the group consisting of compounds represented by Formula 2, compounds represented by Formula 3, and compounds represented by Formula 4 LixCo1-y-zNiyMzO2-αXα Formula 2 LixMn2-yMyO4-αXα Formula 3 LixCo2-yMyO4-αXα Formula 4 wherein 0.90≦x≦1.1, 0≦y≦0.9, 0≦z≦0.5, 0≦α≦2, M is selected from the group consisting of Al, Ni, Mn, Cr, Fe, Mg, Sr, V, rare earth elements and mixtures thereof, and X is selected from the group consisting of O, F, S, P and combinations thereof ### Claim 12 A composite cathode active material comprising: at least one large diameter active material selected from the group consisting of compounds represented by Formula 1 and compounds represented by Formula 2; and at least one small diameter active material comprising a carbon-based material selected from the group consisting of graphite, hard carbon, carbon black, carbon fiber, carbon nanotubes (CNT) and mixtures thereof, the at least one small diameter active material further comprising a material selected from the group consisting of LiNi1/3Co1/3Mn1/3O2, LiMn2O4, LiNi0.5Mn0.5O2, LiC0.95Mg0.05O2, LiNi1/2Mn3/2O4 and mixtures thereof; wherein a ratio of an average particle diameter of the large diameter active material to an average particle diameter of the small diameter active material ranges from about 6:1 to about 100:1; LixCo1-yMyO2-αXα Formula 1 LixCo1-y-zNiyMzO2-αXα Formula 2 wherein 0.90≦x≦1.1, 0≦y≦0.9, 0≦z≦0.5, 0≦α≦2, M is selected from the group consisting of Al, Ni, Mn, Cr, Fe, Mg, Sr, V, rare earth elements and mixtures thereof, and X is selected from the group consisting of O, F, S, P and combinations thereof. ### Claim 13 A composite cathode active material comprising: at least one large diameter active material selected from the group consisting of compounds represented by Formula 1 and compounds represented by Formula 2, wherein a pressed density of the large diameter active material ranges from about 2.5 to about 4.0 g/cm 3; and at least one small diameter active material comprising a carbon-based material selected from the group consisting of graphite, hard carbon, carbon black, carbon fiber, carbon nanotubes (CNT) and mixtures thereof, wherein a pressed density of the small diameter active material ranges from about 1.0 to about 4.0 g/cm 3; wherein a ratio of an average particle diameter of the large diameter active material to an average particle diameter of the small diameter active material ranges from about 6:1 to about 100:1 LixCo1-yMyO2-αXα Formula 1 LixCo1-y-zNiyMzO2-αXα Formula 2 wherein 0.90≦x≦1.1, 0≦y≦0.9, 0≦z≦0.5, 0≦α≦2, M is selected from the group consisting of Al, Ni, Mn, Cr, Fe, Mg, Sr, V, rare earth elements and mixtures thereof, and X is selected from the group consisting of O, F, S, P and combinations thereof.