# US 12,002,936 B2 · Method for separating individual cathode-active materials from li-ion batteries > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,002,936 B2 - Document ID: US12002936B2 - Status: Granted - Kind: B2 - Application number: 16/985,028 - Filed: 2020-08-04 - Published: 2022-02-10 - Granted: 2024-06-04 - Earliest claimed: 2020-08-04 - Assignees: Uchicago Argonne, LLC; Michigan Technological University - Applicants: Uchicago Argonne, LLC; Michigan Technological University - Inventors: Lei Pan; Tinuade Ololade Folayan; Jeffrey S. Spangenberger; Bryant J. Polzin - Web page: https://patentgrep.com/patent/US12002936B2 ## CPC - H01M 10/54: Reclaiming serviceable parts of waste accumulators - B03D 1/023: {Carrier flotation; Flotation of a carrier material to which the target material attaches} - C01B 25/45: containing plural metal, or metal and ammonium - C01G 53/42: containing alkali metals, e.g. LiNiO2 - C01G 53/44: containing manganese - H01M 10/0525: Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries - B03D 2201/02: Collectors - B03D 2201/04: Frothers - C01P 2006/40: Electric properties - C01P 2006/80: Compositional purity - H01M 2004/028: {Positive electrodes} - Y02E 60/10: Energy storage using batteries - Y02W 30/84: Recycling of batteries or fuel cells - H01M: PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY - B03D: FLOTATION; DIFFERENTIAL SEDIMENTATION (sedimentation in general B01D21/00; in combination with other separation of solids B03B; sink-float separation B03B5/28; detergents, soaps C11D) - C01B: NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; {METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C} - C01G: COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F (metal hydrides {monoborane, diborane or addition complexes thereof} C01B6/00; salts of oxyacids of halogens C01B11/00; peroxides, salts or peroxyacids C01B15/00; thiosulfates, dithionites, polythionates C01B17/64; compounds containing selenium, or tellurium C01B19/00; binary compounds of nitrogen with metals C01B21/06; azides C01B21/08; {compounds containing nitrogen, other non-metals and metal C01B21/082}; metal amides C01B21/092; nitrites C01B21/50; {compounds of noble gases C01B23/0005}; phosphides C01B25/08; salts of oxyacids of phosphorus C01B25/16; carbides C01B32/90; compounds containing silicon C01B33/00; compounds containing boron C01B35/00; compounds having molecular sieve properties but not having base-exchange properties C01B37/00; compounds having molecular sieve and base-exchange properties, e.g. crystalline zeolites, C01B39/00; cyanides C01C3/08; salts of cyanamide C01C3/16; thiocyanates C01C3/20) - C01P: INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS - Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION - Y02W: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT ## Abstract Method of separating individual cathode active materials from a mixture of cathode active materials by froth flotation has been developed. They are based on using appropriate chemical reagents that selectively hydrophobize individual cathode active materials to be recovered, so that they can be collected by air bubbles used in flotation and separated from other mixtures. The chemical reagents are amphiphilic molecules with specialized head groups have a strong affinity to metal elements on surfaces of cathode materials. This method enables a separation of individual cathode active material from a mixture of cathode active materials. ## Claims ### Claim 1 A method of processing lithium-ion batteries comprising: Forming a cathode composite slurry comprising a liquid and 1-20 wt % of two or more cathode active materials; Modifying at least one of the two or more cathode active materials to be hydrophobic; Adding a frother chemical to the cathode composite slurry; Aerating the cathode composite slurry, forming a froth and a tailing; Separating the froth; and Drying the froth to collect a first cathode active material of the two or more cathode active materials; Wherein modifying at least one of the two or more cathode active materials comprises interaction of the at least one of the two or more cathode active materials with a collector chemical. ### Claim 2 (depends on 1) The method of claim 1, wherein the cathode composite slurry has a pH of 7-12. ### Claim 3 (depends on 1) The method of claim 1, wherein the collector chemical is a chelating agent. ### Claim 4 (depends on 1) The method of claim 1, wherein the collector chemical is selected from the group consisting of hydroxamic acid, phosphonate, and phosphate. ### Claim 5 (depends on 1) The method of claim 1, wherein aerating comprises forming air bubbles with diameters less than 1 mm. ### Claim 6 (depends on 1) The method of claim 1, wherein aerating comprises bubbling inert gas or air at a rate of 1-5 liters per minute per 1 liter of cathode composite slurry for 5 to 20 minutes. ### Claim 7 (depends on 1) The method of claim 1 wherein the frother comprises methyl isobutyl carbinol (MIBC) or polyglycol (PPG). ### Claim 8 (depends on 1) The method of claim 1 further comprising: drying the tailing to form tailing solids comprising one or more cathode active materials; forming a second cathode composite slurry comprising a liquid and 1-20 wt % of the one or more cathode active materials; modifying at least one of the one or more cathode active materials to be hydrophobic; adding a second frother chemical to the cathode composite slurry; aerating the second cathode composite slurry, forming a second froth and a second tailing; separating the second froth from the second tailing; and drying the second froth to collect a second cathode active material of the two or more cathode active materials. ### Claim 9 (depends on 8) The method of claim 8, wherein modifying at least one of the one or more cathode active materials comprises interaction of the at least one of the one or more cathode active materials with a second collector chemical. ### Claim 10 (depends on 9) The method of claim 9, wherein the second collector chemical is different from the collector chemical. ### Claim 11 A method of processing lithium-ion batteries comprising: Preparing cathode active material from a lithium-ion battery by: Draining liquid components of the lithium-ion battery; Physically separating components of the lithium-ion battery forming a mixture of anode and cathode powders; Separating the anode powder from the cathode powder forming a mixed cathode powder comprising two or more cathode active materials; and Collecting one of the two or more cathode active materials by: Mixing the mixed cathode powder with a liquid to form a slurry having 1-20 wt % solid; Modifying at least one of the two or more cathode active materials of the mixed cathode powder to be hydrophobic; Adding a frothing agent to the slurry; Aerating the slurry for 5 to 20 minutes, forming a froth; Collecting the froth; and Concentrating at least one of the two or more cathode active materials from the froth; Wherein modifying at least one of the two or more cathode active materials comprises interacting at least one of the two or more cathode active materials with a collector chemical. ### Claim 12 (depends on 11) The method of claim 11, wherein the slurry has a pH of 7-12. ### Claim 13 (depends on 11) The method of claim 11, wherein the collector chemical is a chelating agent. ### Claim 14 (depends on 13) The method of claim 13, wherein the collector chemical is selected from the group consisting of hydroxamic acid, phosphonate, and phosphate. ### Claim 15 (depends on 11) The method of claim 11, wherein aerating comprises forming air bubbles with diameters less than 1 mm. ### Claim 16 (depends on 11) The method of claim 11, wherein aerating comprises bubbling inert gas or air at a rate of 1-5 liters per minute per 1 liter of the slurry for 5 to 20 minutes. ### Claim 17 (depends on 11) The method of claim 11, wherein the frother comprises methyl isobutyl carbinol (MIBC) or polyglycol (PPG).