# US 5,702,679 A · Method of preparing Li.sub.1+X- Mn.sub.2-X O.sub.4 for use as secondary battery > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 5,702,679 A - Document ID: US5702679A - Status: Granted - Kind: A - Application number: 08/540,116 - Filed: 1995-10-06 - Granted: 1997-12-30 - Earliest claimed: 1995-10-06 - Assignees: Kerr-McGee Chemical Corporation - Inventors: Stephen W. Sheargold; Terrell N. Andersen - Web page: https://patentgrep.com/patent/US5702679A ## CPC - H01M 4/505: of mixed oxides or hydroxides containing manganese for inserting or intercalating light metals, e.g. LiMn2O4 or LiMn2OxFy - C01G 45/1242: of the type (Mn2O4)-, e.g. LiMn2O4 or Li(MxMn2-x)O4 - C01P 2002/32: spinel-type (AB2O4) - C01P 2002/72: by d-values or two theta-values, e.g. as X-ray diagram - C01P 2002/77: by unit-cell parameters, atom positions or structure diagrams - C01P 2006/40: Electric properties - H01M 4/131: Electrodes based on mixed oxides or hydroxides, or on mixtures of oxides or hydroxides, e.g. LiCoOx - H01M 10/052: Li-accumulators - Y02E 60/10: Energy storage using batteries - H01M: PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY - 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 ## Abstract A continuous method of preparing a single phase lithiated manganese oxide intercalation compound of the formula Li.sub.1+x Mn.sub.2-x O.sub.4 comprising the steps of: mixing intimately a lithium hydroxide or a lithium salt and a manganese oxide or a manganese salt; feeding the intimately mixed salts to a reactor; continuously agitating the mixed salts in the reactor; heating the agitated mixed salts in the reactor at a temperature of from about 650.degree. C. to about 800.degree. C. for a time not in excess of about 4 hours in an oxygen-containing atmosphere; and cooling the reacted product to less than about 200.degree. C. in an oxygen-containing atmosphere for a time not in excess of about 2 hours. ## Claims ### Claim 1 A continuous method of preparing a single phase lithiated manganese oxide intercalation compound of the formula Li.sub.1+x Mn.sub.2-x O.sub.4 having a spinel-type structure comprising the steps of: (a) mixing intimately in amounts, based on said lithiated manganese oxide compound, a lithium hydroxide or a lithium salt and a manganese oxide or a manganese salt; (b) feeding the intimately mixed compounds to a reactor; (c) continuously agitating the mixed compounds in the reactor; (d) heating the agitated mixed compounds in the reactor in the presence of air or an oxygen-enriched atmosphere at a temperature of from about 650.degree. C. to about 800.degree. C. for a time not in excess of about 4 hours to form; (e) cooling the reacted product to less than about 200.degree. C. in less than about 2 hours; wherein x is from about 0.0328 to about 0.125 and the a-axis lattice parameter is about 8.235 .ANG. or less. ### Claim 2 (depends on 1) The method according to claim 1 further including cooling the reacted product to less than about 100.degree. C. ### Claim 3 (depends on 1) The method according to claim 1 further including after the cooling step the step of removing the cooled product from the reactor. ### Claim 4 (depends on 1) The method according to claim 1 wherein step (a) is performed by a rotating drum mixer. ### Claim 5 (depends on 1) The method according to claim 1 wherein step (a) is performed by a ball mill. ### Claim 6 (depends on 1) The method according to claim 1 wherein step (a) is performed by a vibratory mill. ### Claim 7 (depends on 1) The method according to claim 1 wherein step (a) is performed by a jet mill. ### Claim 8 (depends on 1) The method according to claim 1 wherein feeding step (b) is performed by a screw feeder. ### Claim 9 (depends on 1) The method according to claim 1 wherein feeding step (b) is performed by a pneumatic conveyor. ### Claim 10 (depends on 1) The method according to claim 1 wherein feeding step (b) is performed by a pulsed air jet. ### Claim 11 (depends on 1) The method according to claim 1 wherein the atmosphere is continuously purged with a flow of air, oxygen or oxygen-enriched air during step (c). ### Claim 12 (depends on 1) The method according to claim 1 wherein the atmosphere is continuously purged with a countercurrent flow of oxygen enriched atmosphere during step (c). ### Claim 13 (depends on 1) The method according to claim 1 wherein the reactor is a horizontal rotary tube with the exit end slightly lower than the entrance end. ### Claim 14 (depends on 1) The method according to claim 1 wherein the reactor is a horizontal calciner with a rotating screw. ### Claim 15 (depends on 1) The method according to claim 1 wherein the reactor is a fluidized bed. ### Claim 16 (depends on 1) The method according to claim 1 wherein the reactor is a heated vibratory conveyor belt. ### Claim 17 (depends on 1) The method according to claim 1 wherein the reactor is a cascade of vertical rotating hearths. ### Claim 18 (depends on 1) The method according to claim 1 wherein the heating step is performed in about 2 hours or less. ### Claim 19 (depends on 1) The method according to claim 1 wherein the heating step is performed in about one and one-half hours or less. ### Claim 20 (depends on 19) The method according to claim 19 wherein the heating step temperature is from about 700.degree. C. to about 800.degree. C. ### Claim 21 (depends on 1) The method according to claim 1 including continuous purging with a flow of air, oxygen or oxygen-enriched atmosphere during step (d). ### Claim 22 (depends on 21) The method according to claim 21 wherein the continuous purging is with a countercurrent flow of air. ### Claim 23 (depends on 1) The method according to claim 1 wherein the cooling step is performed in a horizontal calciner with a rotating screw. ### Claim 24 (depends on 1) The method according to claim 1 wherein the cooling step is performed in a fluidized bed. ### Claim 25 (depends on 1) The method according to claim 1 wherein the cooling step is performed in a rotary kiln. ### Claim 26 (depends on 1) The method according to claim 1 wherein the cooling step is performed in a heated vibratory conveyor belt. ### Claim 27 (depends on 1) The method according to claim 1 wherein the cooling step is performed in a cascade of vertical rotating hearths. ### Claim 28 (depends on 1) The method according to claim 1 wherein the cooling step is performed in about one and one-half hours or less. ### Claim 29 (depends on 1) The method according to claim 1 wherein said cooling step is performed in less than about 1 and 1/2 hours. ### Claim 30 (depends on 1) The method according to claim 1 wherein the cooling step is performed in zones of progressively cooler temperatures. ### Claim 31 (depends on 30) The method according to claim 30 wherein the cooling step is performed in at least two zones. ### Claim 32 (depends on 31) The method according to claim 31 wherein the temperature in each progressive cooling zone is at least about 90.degree. C. lower than the immediately previous zone. ### Claim 33 (depends on 32) The method according to claim 32 wherein the temperatures in the progressive cooling zones are about: 725.degree. C., 625.degree. C., and 525.degree. C. ### Claim 34 (depends on 32) The method according to claim 32 wherein the temperatures in the progressive cooling zones are about: 800.degree. C., 650.degree. C., and 500.degree. C. ### Claim 35 (depends on 32) The method according to claim 32 wherein the temperatures in the progressive cooling zones are about: 750.degree. C., 600.degree. C., and 450.degree. C. ### Claim 36 (depends on 32) The method according to claim 32 for preparing a spinel structure lithiated intercalation compound of the formula Li.sub.1+x Mn.sub.2-x O.sub.4 wherein said cooled product is annealed by allowing the product to uptake oxygen. ### Claim 37 (depends on 36) The method according to claim 36 wherein said cooled product is annealed by allowing the product to uptake the maximum amount of oxygen. ### Claim 38 (depends on 1) The method according to claim 1 wherein the atmosphere is continuously purged with a flow of air, oxygen or an oxygen-enriched atmosphere during the cooling step. ### Claim 39 (depends on 38) The method according to claim 38 wherein the atmosphere is continuously purged with a countercurrent flow of air during the cooling step. ### Claim 40 (depends on 1) The method according to claim 1 wherein the manganese oxide or manganese salt is selected from the group consisting of MnO.sub.2, MnCO.sub.3, Mn.sub.2 O.sub.3, Mn.sub.3 O.sub.4, MnO, manganese acetate and mixtures thereof. ### Claim 41 (depends on 1) The method according to claim 1 wherein the manganese oxide has been heat treated prior to step (a). ### Claim 42 (depends on 1) The method according to claim 1 wherein the lithium hydroxide or lithium salt is selected from the group consisting of LiOH, Li.sub.2 CO.sub.3, LiNO.sub.3 and mixtures and hydrates thereof. ### Claim 43 (depends on 41) The method of claim 41 wherein the MnO.sub.2 is neutralized by LiOH or NH.sub.4 OH during its synthesis. ### Claim 44 (depends on 1) The method according to claim 1 which comprises the additional steps, prior to said cooling step, of: (i) removing the product from the reactor; and (ii) transferring the reacted product to a separate vessel. ### Claim 45 (depends on 1) The method according to claim 1 wherein heating step (d) is performed in zones of progressively warmer temperatures. ### Claim 46 (depends on 45) The method according to claim 45 wherein the heating step is performed in at least four zones. ### Claim 47 (depends on 46) The method according to claim 46 wherein the temperature in each progressive heating zone is at least 25.degree. higher than the immediately previous zone. ### Claim 48 (depends on 45) The method according to claim 45 wherein the agitated mixed compounds remain in each zone at least about 30 minutes. ### Claim 49 A method of synthesizing a lithium manganese oxide of the formula Li.sub.1+x Mn.sub.2-x O.sub.4 having a spinel-type crystal structure with an a-axis lattice parameter of about 8.235 .ANG. or less, and wherein x is from about 0.0328 to about 0.125 comprising forming an intimate mixture in finely divided solid form of at least one lithium hydroxide or lithium salt reactant selected from the group consisting of LiOH, Li.sub.2 CO.sub.3, LiNO.sub.3 and mixtures thereof and at least one manganese oxide or manganese salt reactant selected from the group consisting of MnO.sub.2, Mn.sub.2 O.sub.3, MnCO.sub.3, Mn.sub.3 O.sub.4, MnO, manganese acetate and mixtures thereof and continuously agitating and heating the mixure in a reactor under a continuous purge of countercurrent air at a temperature in the range of from about 650.degree. C. to about 800.degree. C. for a period not in excess of about 4 hours to cause said reactants to react with each other to form said lithium manganese oxide. ### Claim 50 (depends on 49) The method according to claim 49, wherein the heating of the mixture is in air at a temperature of from about 700.degree. C. to about 800.degree. C., the mixture being held at the maximum temperature for a period of less than about 2 hours. ### Claim 51 (depends on 49) The method according to claim 49 wherein the manganese oxide has been heat treated prior to forming the mixture. ### Claim 52 (depends on 49) The method according to claim 49, wherein the Li.sub.1+x Mn.sub.2-x O.sub.4 has a (Mn.sub.2)O.sub.4 (Mn.sub.2)O.sub.4.sup.n-1 framework structure in which the quantity of Mn cations varies from the stoichiometric value. ### Claim 53 (depends on 49) A lithium manganese oxide having a spinel crystal structure, synthesized by the method of claim 49. ### Claim 54 A method of preparing a single phase lithiated manganese oxide intercalation compound of the formula Li.sub.1+x Mn.sub.2-x O.sub.4 having a spinel-type structure by a batch process comprising the steps of (a) fixing intimately in stoichiometric mounts, based on said lithiated manganese oxide compound, a lithium hydroxide or a lithium salt and a manganese oxide or a manganese salt; (b) feeding the intimately mixed compounds to a reactor; (c) agitating the mixed compounds in the reactor; (d) heating the agitated mixed compounds in the reactor in the presence of air or an oxygen-enriched atmosphere at a temperature of from about 650.degree. C. to about 800.degree. C. for a time not in excess of about 4 hours to form an oxygen deficient spinel structure intercalation compound; and (e) cooling the oxygen deficient product to less than about 100.degree. C. in about 2 hours or less; to form Li.sub.1+x Mn.sub.2-x O.sub.4 wherein x is from about 0.0328 to about 0.125 and the a-axis lattice parameter is about 8.235 .ANG. or less. ### Claim 55 (depends on 54) The method according to claim 54 wherein the cooling vessel is a horizontal calciner with a rotating screw. ### Claim 56 (depends on 54) The method according to claim 54 wherein the cooling vessel is a fluidized bed. ### Claim 57 (depends on 54) The method according to claim 54 wherein the cooling vessel is a heated vibratory conveyor belt. ### Claim 58 (depends on 54) The method according to claim 54 wherein the cooling vessel is a cascade of vertical rotating hearths. ### Claim 59 (depends on 54) The method according to claim 54 wherein the cooling vessel is a rotary kiln. ### Claim 60 (depends on 54) The method according to claim 54 wherein the cooling step is performed in about one and one-half hours or less. ### Claim 61 (depends on 54) The method according to claim 54 wherein said cooling step is performed in less than about 1 hour.