# US 2017/0288229 A1 · Sulfur based cathode composite material and method for making the same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2017/0288229 A1 - Document ID: US20170288229A1 - Status: Published application - Kind: A1 - Application number: 15/627,276 - Filed: 2017-06-19 - Published: 2017-10-05 - Earliest claimed: 2014-12-19 - Assignees: Jiangsu Huadong Institute of Li-Ion Battery Co., Ltd.; Tsinghua University - Applicants: Jiangsu Huadong Institute of Li-Ion Battery Co., Ltd.; Tsinghua University - Inventors: Li Wang; Xiang-Ming He; Yu-Mei Ren; Jian-Jun Li; Fang-Xu Wu; Yu-Ming Shang; Yuan-Qing Li; Tuan-Wei Li; Shu-Hui Wang - Web page: https://patentgrep.com/patent/US20170288229A1 ## CPC - H01M 4/602: {Polymers} - C08F 120/44: Acrylonitrile - C08J 3/203: {Solid polymers with solid and/or liquid additives} - C08J 3/212: {and solid additives} - C08K 3/04: Carbon - C08K 3/06: Sulfur - H01M 4/137: Electrodes based on electro-active polymers - H01M 4/1399: of electrodes based on electro-active polymers - H01M 4/362: {Composites} - H01M 4/38: of elements or alloys - H01M 4/625: {Carbon or graphite} - C08J 2333/20: Homopolymers or copolymers of acrylonitrile (C08J2355/02 takes precedence) - C08K 3/041: {Carbon nanotubes} - C08K 2201/001: Conductive additives - C08K 2201/005: Additives being defined by their particle size in general - H01M 4/0404: {by coating on electrode collectors} - H01M 4/382: {Lithium (H01M4/405 takes precedence)} - H01M 10/052: Li-accumulators - 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 - C08F: MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS - C08J: WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H (working, e.g. shaping, of plastics B29) - C08K: Use of inorganic or non-macromolecular organic substances as compounding ingredients (paints, inks, varnishes, dyes, polishes, adhesives C09) - Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION ## Abstract A method for making a sulfur based cathode composite material is disclosed. Polyacrylonitrile and elemental sulfur are dissolved together in a first solvent to form a first solution. An electrically conductive carbonaceous material is added to the first solution to mix with the polyacrylonitrile and the elemental sulfur. An environment in which the polyacrylonitrile and the elemental sulfur are located in is changed to reduce a solubility of the polyacrylonitrile and the elemental sulfur in a changed environment to simultaneously precipitate the polyacrylonitrile and the elemental sulfur, thereby forming a precipitate having the electrically conductive carbonaceous material. The precipitate is heated to chemically react the polyacrylonitrile with the elemental sulfur. A sulfur based cathode composite material is also disclosed. ## Claims ### Claim 1 A sulfur based cathode composite material comprising a dehydrocyclized polyacrylonitrile, an elemental sulfur, and an electrically conductive carbonaceous material. ### Claim 2 (depends on 1) The sulfur based cathode composite material of claim 1, wherein a weight percentage of the dehydrocyclized polyacrylonitrile is about 30% to about 70%, a weight percentage of the elemental sulfur is about 30% to about 70%, and a weight percentage of the electrically conductive carbonaceous material is about 1% to about 20%. ### Claim 3 (depends on 1) The sulfur based cathode composite material of claim 1, wherein the electrically conductive carbonaceous material is selected from the group consisting of carbon nanotubes, graphenes, acetylene black, carbon black, and combinations thereof. ### Claim 4 (depends on 1) The sulfur based cathode composite material of claim 1, wherein a size of the electrically conductive carbonaceous material is less than or equal to 1 microns. ### Claim 5 A method for making a sulfur based cathode composite material comprising: dissolving polyacrylonitrile and elemental sulfur together in a first solvent to form a first solution; adding an electrically conductive carbonaceous material to the first solution to mix with the polyacrylonitrile and the elemental sulfur; changing an environment of the polyacrylonitrile and the elemental sulfur to reduce a solubility of the polyacrylonitrile and the elemental sulfur and simultaneously precipitate the polyacrylonitrile and the elemental sulfur, thereby forming a precipitate having the electrically conductive carbonaceous material; and heating the precipitate to chemically react the polyacrylonitrile with the elemental sulfur. ### Claim 6 (depends on 5) The method of claim 5, wherein a shape of the electrically conductive carbonaceous material is powder or particles having a size less than or equal to 5 microns. ### Claim 7 (depends on 5) The method of claim 5, wherein a material of the electrically conductive carbonaceous material is selected from the group consisting of carbon nanotubes, graphenes, acetylene black, carbon black, and combinations thereof. ### Claim 8 (depends on 1) The method of claim 1, wherein an amount of the electrically conductive carbonaceous material is less than or equal to 10% of a total mass of the polyacrylonitrile and the elemental sulfur. ### Claim 9 (depends on 1) The method of claim 1, wherein the changing the environment comprises transferring the first solution to the second solvent, the polyacrylonitrile and the elemental sulfur are insoluble or less soluble in the second solvent than in the first solvent. ### Claim 10 (depends on 9) The method of claim 9, wherein the temperature of the second solvent is lower than the temperature of the first solution, and a temperature difference between the second solvent and the first solution is greater than or equal to 50° C. ### Claim 11 (depends on 9) The method of claim 9, wherein the first solution is greater than or equal to 100° C. and less than or equal to 200° C., the second solvent is smaller than or equal to 50° C. ### Claim 12 (depends on 9) The method of claim 9, wherein a volume ratio of the first solvent to the second solvent is about 1:1 to about 1:5. ### Claim 13 (depends on 9) The method of claim 9, wherein the second solvent is selected from the group consisting of water, ethanol, methanol, acetone, n-hexane, cyclohexane, diethyl ether, and mixtures thereof. ### Claim 14 (depends on 9) The method of claim 9, wherein a time used for completing the transferring of the first solution to the second solvent is within 10 seconds. ### Claim 15 (depends on 5) The method of claim 5, wherein a total concentration of the polyacrylonitrile and the elemental sulfur in the first solution is in a range from about 10 g/L to about 100 g/L. ### Claim 16 (depends on 5) The method of claim 5, wherein the changing the environment comprises freeze-drying the first solution. ### Claim 17 (depends on 5) The method of claim 5, wherein the changing the environment comprises depressurizing the first solution. ### Claim 18 (depends on 1) The method of claim 1, wherein the heating is in a vacuum or a protective atmosphere at a temperature equal to or above 250° C. ### Claim 19 (depends on 1) The method of claim 1, wherein the forming the precipitate is a physical process without a chemical synthesis of the polyacrylonitrile and the elemental sulfur.