WO2024066809A1 - Matériau d'électrode positive, son procédé de préparation, feuille d'électrode positive, batterie secondaire et dispositif électronique - Google Patents

Matériau d'électrode positive, son procédé de préparation, feuille d'électrode positive, batterie secondaire et dispositif électronique Download PDF

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WO2024066809A1
WO2024066809A1 PCT/CN2023/114243 CN2023114243W WO2024066809A1 WO 2024066809 A1 WO2024066809 A1 WO 2024066809A1 CN 2023114243 W CN2023114243 W CN 2023114243W WO 2024066809 A1 WO2024066809 A1 WO 2024066809A1
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metal
coating
ions
cobalt
nickel
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PCT/CN2023/114243
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English (en)
Chinese (zh)
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徐士民
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天津巴莫科技有限责任公司
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Publication of WO2024066809A1 publication Critical patent/WO2024066809A1/fr

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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H01M4/362—Composites
    • H01M4/366—Composites as layered products
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
    • H01M4/131—Electrodes based on mixed oxides or hydroxides, or on mixtures of oxides or hydroxides, e.g. LiCoOx
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H01M4/48—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides
    • H01M4/50—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of manganese
    • H01M4/505—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of manganese of mixed oxides or hydroxides containing manganese for inserting or intercalating light metals, e.g. LiMn2O4 or LiMn2OxFy
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H01M4/48—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides
    • H01M4/52—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of nickel, cobalt or iron
    • H01M4/525—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of nickel, cobalt or iron of mixed oxides or hydroxides containing iron, cobalt or nickel for inserting or intercalating light metals, e.g. LiNiO2, LiCoO2 or LiCoOxFy
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M2004/026—Electrodes composed of, or comprising, active material characterised by the polarity
    • H01M2004/028—Positive electrodes
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10—Energy storage using batteries

Definitions

  • the present application relates to the field of electrochemical technology, and in particular to a positive electrode material and a preparation method thereof, a positive electrode sheet, a secondary battery and an electronic device.
  • Nickel cobalt lithium manganese oxide ternary material is a major positive electrode material, but the structural stability of nickel cobalt lithium manganese oxide ternary material is poor during the cycle process, which can easily lead to a decrease in the cycle performance of secondary batteries, a decrease in the mileage of electric vehicles, and premature scrapping of ternary material power batteries, which seriously limits its development and application in electric vehicles.
  • the present application provides a positive electrode material and a preparation method thereof, a positive electrode plate, a secondary battery and an electronic device, aiming to improve the structural stability of the positive electrode material during the cycle process, thereby improving the cycle performance of the secondary battery.
  • the first aspect of the present application provides a positive electrode material, comprising:
  • a coating structure formed on at least a portion of the surface of the inner core wherein the coating structure includes a first coating layer, a second coating layer, a third coating layer, a fourth coating layer and a fifth coating layer stacked sequentially from the inner core outward in a radial direction;
  • the first coating layer contains an oxide of a first metal
  • the second coating layer contains a second doped metal of lithium nickel cobalt manganese oxide
  • the third coating layer contains an oxide of a third metal
  • the fourth coating layer contains a third doped metal of lithium nickel cobalt manganese oxide
  • the fifth coating layer contains at least one of an oxide, fluoride and phosphate of a fifth metal
  • the first metal, the third metal and the fifth metal are of the same or different types.
  • the positive electrode material satisfies at least one of the following conditions:
  • the median particle size D 1 50 of the positive electrode material is 5 ⁇ m to 35 ⁇ m;
  • the median particle size D 2 50 of the inner core of the nickel-cobalt-lithium manganese oxide composite is 0.1 ⁇ m to 10 ⁇ m;
  • the second coating layer further comprises a second doping metal, and optionally, the second doping metal comprises one or more of magnesium, aluminum, copper, indium, antimony, bismuth, barium, tungsten, palladium, strontium, cerium, niobium, scandium, gallium, silver, vanadium, zinc, germanium and molybdenum;
  • the fourth coating layer further comprises a third doping metal.
  • the third doping metal comprises one or more of magnesium, aluminum, copper, indium, antimony, bismuth, barium, tungsten, palladium, strontium, cerium, niobium, scandium, gallium, silver, vanadium, zinc, germanium and molybdenum;
  • the thickness of the first coating layer is 0.01 ⁇ m to 2 ⁇ m;
  • the thickness of the second coating layer is 1 ⁇ m to 30 ⁇ m;
  • the thickness of the third coating layer is 0.01 ⁇ m to 2 ⁇ m;
  • the thickness of the fourth coating layer is 1 ⁇ m to 30 ⁇ m;
  • the fifth coating layer has a thickness of 0.01 ⁇ m to 5 ⁇ m.
  • the positive electrode material satisfies at least one of the following conditions:
  • the nickel-cobalt-lithium manganese oxide composite contains a first doping metal, wherein the first doping metal includes one or more of sodium, potassium, calcium, magnesium, aluminum, copper, indium, antimony, bismuth, barium, tungsten, palladium, strontium, cerium, niobium, scandium, gallium, silver, vanadium, zinc, germanium and molybdenum;
  • the first metal includes one or more of calcium, iron, copper, aluminum, zirconium, magnesium, indium, antimony, bismuth, barium, tungsten, palladium, strontium, cerium, niobium, scandium, gallium, silver, vanadium, zinc, germanium and molybdenum;
  • the third metal includes one or more of calcium, iron, copper, aluminum, zirconium, magnesium, indium, antimony, bismuth, barium, tungsten, palladium, strontium, cerium, niobium, scandium, gallium, silver, vanadium, zinc, germanium and molybdenum;
  • the fifth metal includes one or more of sodium, potassium, copper, silver, magnesium, aluminum, titanium, vanadium, zinc, germanium, molybdenum, indium, antimony, bismuth, barium, tungsten, palladium, strontium, cerium, niobium, zirconium, scandium, gallium and yttrium.
  • the second aspect of the present application provides a method for preparing a positive electrode material, comprising:
  • the fourth coating material and the lithium source are mixed and calcined to obtain a nickel-cobalt-lithium manganate composite containing a coating layer;
  • the nickel-cobalt-manganese-oxide lithium composite containing a coating layer is subjected to a fifth coating treatment using a coating agent containing a fifth metal, wherein the coating agent containing the fifth metal comprises at least one of an oxide, a fluoride and a phosphate of the fifth metal, to obtain a positive electrode material.
  • the positive electrode material comprises a core of a doped nickel-cobalt-manganese-oxide lithium composite and a coating structure formed on at least a portion of the surface of the core, wherein the coating structure comprises a first coating layer, a second coating layer, a third coating layer, a fourth coating layer and a fifth coating layer stacked sequentially from the core to the outside in a radial direction;
  • the first coating layer contains the oxide of the first metal
  • the second coating layer contains lithium nickel cobalt manganese oxide
  • the third coating layer contains the oxide of the third metal
  • the fourth coating layer contains lithium nickel cobalt manganese oxide
  • the fifth coating layer contains at least one of the oxide, fluoride and phosphate of the fifth metal.
  • the first metal, the third metal and the fifth metal are of the same or different types.
  • the step of providing a doped nickel-cobalt-manganese composite precursor comprises:
  • the nickel ions, cobalt ions and manganese ions are reacted with an aqueous solution of ions of a first doping metal in a first alkaline environment to form the nickel-cobalt-manganese composite precursor.
  • the method satisfies at least one of the following conditions:
  • the nickel ions, the cobalt ions, the manganese ions and the ions of the first doping metal are provided in the form of salts, and optionally, the salts used include at least one of sulfates, acetates, chlorides and nitrates of the corresponding metals;
  • the first alkaline environment includes at least one of a solution of sodium hydroxide, potassium hydroxide, ammonium bicarbonate, ammonium carbonate and aqueous ammonia;
  • the temperature of reacting the nickel ions, cobalt ions and manganese ions with the aqueous solution of ions of the first doping metal in the first alkaline environment is 30° C. to 80° C. and the time is 1 h to 10 h;
  • the molar ratio of the nickel ions, the cobalt ions, the manganese ions and the ions of the first doping metal is (0.3-1):(0.01-0.5):(0.1-0.5):(0.01-0.3);
  • the first doping metal includes one or more of sodium, potassium, calcium, magnesium, aluminum, copper, indium, antimony, bismuth, barium, tungsten, palladium, strontium, cerium, niobium, scandium, gallium, silver, vanadium, zinc, germanium and molybdenum;
  • the median particle size of the nickel-cobalt-manganese composite precursor is 0.1 ⁇ m to 10 ⁇ m.
  • the nickel-cobalt-manganese composite precursor is treated with the first metal ion.
  • the coating process includes:
  • the nickel-cobalt-manganese complex precursor is reacted with an ion aqueous solution of the first metal in a second alkaline environment to form a hydroxide coating layer of the first metal on at least a portion of the surface of the nickel-cobalt-manganese complex precursor to obtain the first coating.
  • the method satisfies at least one of the following conditions:
  • the first metal includes one or more of calcium, iron, copper, aluminum, zirconium, magnesium, indium, antimony, bismuth, barium, tungsten, palladium, strontium, cerium, niobium, scandium, gallium, silver, vanadium, zinc, germanium and molybdenum;
  • the first metal ion is provided in the form of a salt, and optionally, the salt used includes at least one of a sulfate, an acetate, a chloride and a nitrate of the corresponding metal;
  • the temperature of the nickel-cobalt-manganese composite precursor contacting the first metal ions in the second alkaline environment is 20° C. to 40° C., and the time is 1 h to 5 h;
  • the thickness of the first metal hydroxide coating layer is 0.01 ⁇ m to 2 ⁇ m.
  • the second coating treatment of the first coating with nickel ions, cobalt ions, and manganese ions includes:
  • the first coating is reacted with an aqueous solution of ions of a second doping metal, nickel ions, cobalt ions, and manganese ions in a third alkaline environment to form a nickel-cobalt-manganese hydroxide layer doped with the second doping metal on at least a portion of the surface of the first coating to obtain the second coating.
  • the method satisfies at least one of the following conditions:
  • the second doping metal includes one or more of sodium, potassium, calcium, magnesium, aluminum, copper, indium, antimony, bismuth, barium, tungsten, palladium, strontium, cerium, niobium, scandium, gallium, silver, vanadium, zinc, germanium and molybdenum;
  • the ions of the second doping metal are provided in the form of a salt, and optionally, the salt used includes at least one of a sulfate, an acetate, a chloride and a nitrate of the corresponding metal;
  • the third alkaline environment comprises at least one of a solution of sodium hydroxide, potassium hydroxide, ammonium bicarbonate, ammonium carbonate and aqueous ammonia;
  • the temperature of reacting the first coating with the aqueous solution of the second doping metal ions, nickel ions, cobalt ions, and manganese ions in the third alkaline environment is 30° C. to 80° C. and the time is 1 h to 10 h;
  • the molar ratio of the nickel ions, the cobalt ions, the manganese ions and the ions of the second doping metal is (0.3-1):(0.01-0.5):(0.1-0.5):(0.01-0.3);
  • the median particle size of the second coating is 1 ⁇ m to 30 ⁇ m.
  • the third coating treatment of the second coating with ions of a third metal includes:
  • the second coating is reacted with an aqueous solution of ions of the third metal in a fourth alkaline environment to form a hydroxide coating layer of the third metal on at least a portion of the surface of the second coating to obtain the third coating.
  • the method satisfies at least one of the following conditions:
  • the third metal includes one or more of calcium, iron, copper, aluminum, zirconium, magnesium, indium, antimony, bismuth, barium, tungsten, palladium, strontium, cerium, niobium, scandium, gallium, silver, vanadium, zinc, germanium and molybdenum;
  • the third metal ion is provided in the form of a salt, and optionally, the salt used includes at least one of a sulfate, an acetate, a chloride and a nitrate of the corresponding metal;
  • the temperature at which the second coating reacts with the aqueous solution of the third metal ions in the fourth alkaline environment is 20°C ⁇ 40°C, time is 1h ⁇ 5h;
  • the thickness of the third metal hydroxide coating layer is 0.01 ⁇ m to 2 ⁇ m.
  • the fourth coating treatment of the third coating with nickel ions, cobalt ions, and manganese ions includes:
  • the third coating is reacted with an aqueous solution of ions of a third doping metal, nickel ions, cobalt ions, and manganese ions in a fifth alkaline environment to form a nickel-cobalt-manganese hydroxide layer doped with the third doping metal on at least a portion of the surface of the third coating to obtain the fourth coating.
  • the method satisfies at least one of the following conditions:
  • the third doping metal includes one or more of sodium, potassium, calcium, magnesium, aluminum, copper, indium, antimony, bismuth, barium, tungsten, palladium, strontium, cerium, niobium, scandium, gallium, silver, vanadium, zinc, germanium and molybdenum;
  • the salt solution of the third doping metal ion includes at least one of sulfate, acetate, chloride and nitrate;
  • the fifth alkaline environment comprises at least one of a solution of sodium hydroxide, potassium hydroxide, ammonium bicarbonate, ammonium carbonate and aqueous ammonia;
  • the temperature of reacting the third coating with the aqueous solution of the third doping metal ions, nickel ions, cobalt ions, and manganese ions in the fifth alkaline environment is 30° C. to 80° C. and the time is 3 h to 20 h;
  • the molar ratio of the nickel ions, the cobalt ions, the manganese ions and the ions of the third doping metal is (0.3-1):(0.01-0.5):(0.1-0.5):(0.01-0.3);
  • the median particle size of the fourth coating is 4 ⁇ m to 30 ⁇ m.
  • the mixed calcination treatment of the fourth coating and the lithium source comprises:
  • the fourth coating is mixed with the lithium source and the fourth doping metal element and calcined to form a core of the nickel-cobalt-lithium manganate composite and the first coating layer covering at least a portion of the surface of the core, and a second coating layer, a third coating layer and a fourth coating layer stacked in sequence in the radial direction of the first coating layer, to obtain the nickel-cobalt-lithium manganate composite containing the coating layer;
  • the fourth doping metal element includes at least one of the first doping element, the second doping element and the third doping element.
  • the method satisfies at least one of the following conditions:
  • the lithium source includes one or more of lithium carbonate, lithium hydroxide, lithium acetate, lithium oxide and lithium nitride;
  • the fourth doping metal element includes one or more of sodium, potassium, copper, silver, magnesium, aluminum, titanium, vanadium, zinc, germanium, molybdenum, indium, antimony, bismuth, barium, tungsten, palladium, strontium, cerium, niobium, zirconium, scandium, gallium and yttrium;
  • the fourth doping metal element is at least one of an oxide, a fluoride, a phosphate, a hydrogen phosphate, a dihydrogen phosphate and an acetate of the fourth doping metal;
  • the calcination temperature is 400° C. to 1500° C. and the calcination time is 5 h to 40 h;
  • the median particle size of the nickel-cobalt-lithium manganese oxide composite containing the coating layer is 5 ⁇ m to 30 ⁇ m.
  • the fifth coating treatment of the nickel-cobalt-manganese-oxide lithium composite containing a coating layer using a coating agent containing a fifth metal comprises:
  • the nickel-cobalt-manganese-oxide lithium composite containing the coating layer is brought into contact with the coating agent containing the fifth metal to form the fifth coating layer containing the fifth metal on at least a portion of the surface of the nickel-cobalt-manganese-oxide lithium composite containing the coating layer by wet coating or dry coating to obtain the positive electrode material.
  • the method satisfies at least one of the following conditions:
  • the fifth metal includes sodium, potassium, copper, silver, magnesium, aluminum, titanium, vanadium, zinc, germanium, molybdenum, indium, antimony, bismuth, barium, tungsten, palladium, One or more of strontium, cerium, niobium, zirconium, scandium, gallium and yttrium;
  • the molar ratio of the nickel-cobalt-manganese-oxide lithium composite containing the coating layer to the coating agent containing the fifth metal is 1:(0.001-0.3);
  • the coating agent containing the fifth metal comprises one or more of an oxide, a fluoride and a phosphate of the fifth metal
  • the temperature of the fifth coating treatment is 300°C to 1000°C.
  • the third aspect of the present application provides a positive electrode plate, comprising the positive electrode material provided in the first aspect of the present application or the positive electrode material prepared by the method described in the second aspect of the present application.
  • the fourth aspect of the present application provides a secondary battery, comprising the positive electrode sheet of the third aspect of the present application.
  • a fifth aspect of the present application provides an electronic device, comprising the secondary battery of the fourth aspect of the present application.
  • the electronic device of the present application includes the secondary battery provided by the present application, and thus has at least the same advantages as the secondary battery.
  • the positive electrode material provided in the present application includes a core of a nickel-cobalt-manganese-oxide lithium composite and a coating structure formed on at least part of the surface of the core, wherein the coating structure includes a first coating layer, a second coating layer, a third coating layer, a fourth coating layer and a fifth coating layer stacked in sequence in the radial direction.
  • the coating layers are combined by electrostatic attraction, ionic bonds and covalent bonds, which is conducive to reducing the cracks and changes in the unit cell parameters of the nickel-cobalt-manganese-oxide lithium crystals during the cycle, reducing the changes in the crystal structure, and making the positive electrode material have a higher structural stability.
  • the nickel cobalt manganese oxide composite, the nickel cobalt manganese oxide contained in the second coating layer, and the nickel cobalt manganese oxide contained in the fourth coating layer provide the main active material components, and can also play a certain role in improving the structural stability of the positive electrode material.
  • the oxide of the first metal contained in the first coating layer and the oxide of the third metal contained in the third coating layer can effectively inhibit the volume change of the positive electrode material during the charge and discharge process, thereby reducing the structural stress of the nickel cobalt manganese oxide crystal caused by the volume change and causing cracks, and maintaining the stability of the crystal structure of the positive electrode material.
  • the oxide, fluoride and phosphate of the fifth metal contained in the fifth coating layer can mainly prevent the infiltration of the electrolyte, thereby effectively preventing the side reaction between the electrolyte and the nickel cobalt manganese oxide from causing powdering, capacity decay and battery gas production, and improving the gram capacity, cycle performance, high temperature performance and safety performance of the positive electrode material.
  • the volume change of the positive electrode material during the cycle can be effectively alleviated, and the penetration of the electrolyte can be prevented, and the reaction between the positive electrode material and the electrolyte can be reduced to generate a new solid electrolyte interface film, thereby reducing the consumption of the electrolyte.
  • it can also reduce the gas production of the secondary battery under high voltage, thereby effectively improving the battery's cycle performance.
  • FIG1 is a SEM image of the precursor core prepared in step (1) of Example 1.
  • FIG. 2 is a graph showing the D50 particle size distribution of the precursor core prepared in step (1) of Example 1.
  • FIG3 is a SEM image of the multilayer precursor prepared in step (5) of Example 1.
  • FIG4 is a graph showing the D50 particle size distribution of the multilayer precursor prepared in step (5) of Example 1.
  • FIG5 is a SEM image of the coated multilayer structure of lithium nickel cobalt manganese oxide prepared in step (7) of Example 1.
  • FIG6 is a powder DSC curve of the charge cut-off voltage of 4.3 V of the positive electrode plate of a thin-film battery with a multilayer structure of nickel cobalt lithium manganese oxide prepared in step (7) of Example 1.
  • FIG. 7 is a comparison curve of the 45° C. cycle capacity retention rate of the thin film batteries of Example 1 and Comparative Examples 1 and 2.
  • FIG8 is a comparison chart of the capacity retention rates of the thin film batteries of Example 1 and Comparative Examples 1 and 2 after storage at 60° C. for 7 days.
  • FIG9 is a charge and discharge curve diagram of the coated multilayer structure nickel cobalt manganese oxide prepared in step (7) of Example 1 and Example 4.
  • FIG10 is a SEM image of the multilayer precursor prepared in step (5) of Example 2.
  • FIG. 11 is a SEM image of the coated multilayer structure of lithium nickel cobalt manganese oxide prepared in step (7) of Example 4.
  • any lower limit can be combined with any upper limit to form an unclearly recorded range; and any lower limit can be combined with other lower limits to form an unclearly recorded range, and any upper limit can be combined with any other upper limit to form an unclearly recorded range.
  • each point or single value between the range endpoints is included in the range.
  • each point or single value can be combined as its own lower limit or upper limit with any other point or single value or with other lower limits or upper limits to form an unclearly recorded range.
  • the inventors found that under long-term cycle and high-temperature conditions, the crystal cells of traditional nickel-cobalt-manganese oxide ternary materials will generate cracks, leading to electrolyte loss and the formation of new positive electrode electrolyte membrane (CEI), which in turn leads to battery gas production and crystal pulverization, ultimately causing the cycle and capacity performance of the material and battery to decline.
  • CEI positive electrode electrolyte membrane
  • a first aspect of an embodiment of the present application provides a positive electrode material, comprising: an inner core of a nickel cobalt lithium manganese oxide composite; and a coating structure formed on at least a portion of the surface of the inner core, wherein the coating structure comprises a first coating layer, a second coating layer, a third coating layer, a fourth coating layer and a fifth coating layer stacked in sequence from the inner core in a radial direction, and the first coating layer is located in the first layer outside the inner core; wherein the first coating layer contains an oxide of a first metal, the second coating layer contains lithium nickel cobalt manganese oxide, the third coating layer contains an oxide of a third metal, the fourth coating layer contains lithium nickel cobalt manganese oxide, and the fifth coating layer contains at least one of an oxide, fluoride and phosphate of a fifth metal, and the types of the first metal, the third metal and the fifth metal are the same or different.
  • the positive electrode material provided in the present application includes a core of a nickel-cobalt-manganese-oxide lithium composite and a coating structure formed on at least part of the surface of the core, wherein the coating structure includes a first coating layer, a second coating layer, a third coating layer, a fourth coating layer and a fifth coating layer stacked in sequence from the core in the radial direction.
  • the coating layers are combined by electrostatic attraction, ionic bonds and covalent bonds, which is conducive to reducing the cracks and changes in the unit cell parameters of the nickel-cobalt-manganese-oxide lithium crystals during the cycle, reducing the changes in the crystal structure, and making the positive electrode material have a higher structural stability.
  • the inner core, the lithium nickel cobalt manganese oxide contained in the second coating layer, and the lithium nickel cobalt manganese oxide contained in the fourth coating layer provide the main active material components, and can also play a certain role in improving the structural stability of the positive electrode material.
  • the oxide of the first metal contained in the first coating layer and the oxide of the third metal contained in the third coating layer can effectively inhibit the volume change of the positive electrode material during the charge and discharge process, thereby reducing the structural stress of the lithium nickel cobalt manganese oxide crystals due to the volume change and causing cracks, and maintaining the stability of the crystal structure of the positive electrode material.
  • the oxide, fluoride and phosphate of the fifth metal contained in the fifth coating layer can mainly prevent the infiltration of the electrolyte, thereby effectively preventing the side reaction between the electrolyte and the lithium nickel cobalt manganese oxide from causing powdering, capacity decay and battery gas production, and improving the gram capacity, cycle performance, high temperature performance and safety performance of the positive electrode material.
  • the volume change of the positive electrode material during the cycle can be effectively alleviated, and the penetration of the electrolyte can be prevented, and the reaction between the positive electrode material and the electrolyte can be reduced to generate a new solid electrolyte interface film, thereby reducing the consumption of the electrolyte.
  • it can also reduce the gas production of the secondary battery under high voltage, thereby effectively improving the battery's cycle performance.
  • the second coating layer further comprises a second doped metal.
  • the second doped metal includes one or more of magnesium, aluminum, copper, indium, antimony, bismuth, barium, tungsten, palladium, strontium, cerium, niobium, scandium, gallium, silver, vanadium, zinc, germanium and molybdenum.
  • the fourth coating layer further comprises a third doping metal, and optionally, the third doping metal comprises magnesium, One or more of aluminum, copper, indium, antimony, bismuth, barium, tungsten, palladium, strontium, cerium, niobium, scandium, gallium, silver, vanadium, zinc, germanium and molybdenum.
  • the doped metal contained in the second coating layer and the fourth coating layer is beneficial to improving the electrical conductivity and ion mobility of the material, thereby improving the cycle performance and high temperature performance of the material.
  • the median particle size D 1 50 of the positive electrode material is 5 ⁇ m to 35 ⁇ m, preferably 8 ⁇ m to 30 ⁇ m.
  • the median particle size D 2 50 of the inner core of the nickel-cobalt-lithium manganese oxide composite is 0.1 ⁇ m to 10 ⁇ m, preferably 0.5 ⁇ m to 8 ⁇ m.
  • the thickness of the first coating layer is 0.01 ⁇ m to 2 ⁇ m, preferably 0.05 ⁇ m to 1.95 ⁇ m.
  • the thickness of the second coating layer is 1 ⁇ m to 30 ⁇ m, preferably 5 ⁇ m to 10 ⁇ m.
  • the thickness of the third coating layer is 0.01 ⁇ m to 2 ⁇ m, preferably 0.05 ⁇ m to 1.95 ⁇ m.
  • the thickness of the fourth coating layer is 1 ⁇ m to 30 ⁇ m, preferably 2 ⁇ m to 25 ⁇ m.
  • the fifth coating layer has a thickness of 0.01 ⁇ m to 5 ⁇ m, preferably 0.5 ⁇ m to 4.5 ⁇ m.
  • the thickness of each coating layer is controlled within a suitable range, which is beneficial to further suppress the volume change of the lithium nickel cobalt manganese oxide crystals during the charging and discharging process, thereby reducing the structural stress generated by the volume change of the crystal and causing cracks, and improving the stability of the crystal structure of the positive electrode material.
  • the lithium nickel cobalt manganese oxide composite contains one or more of the elements sodium, potassium, calcium, magnesium, aluminum, copper, indium, antimony, bismuth, barium, tungsten, palladium, strontium, cerium, niobium, scandium, gallium, silver, vanadium, zinc, germanium and molybdenum.
  • the types of the first metal, the second doped metal, the third metal, the third doped metal and the fifth metal are not specifically limited and can be selected according to actual needs. At the same time, the types of the first metal, the second doped metal, the third metal, the third doped metal and the fifth metal can be the same or different.
  • the first metal may include one or more of calcium, iron, copper, aluminum, zirconium, magnesium, indium, antimony, bismuth, barium, tungsten, palladium, strontium, cerium, niobium, scandium, gallium, silver, vanadium, zinc, germanium, and molybdenum.
  • the third metal may include one or more of calcium, iron, copper, aluminum, zirconium, magnesium, indium, antimony, bismuth, barium, tungsten, palladium, strontium, cerium, niobium, scandium, gallium, silver, vanadium, zinc, germanium, and molybdenum.
  • the fifth metal may include one or more of sodium, potassium, copper, silver, magnesium, aluminum, titanium, vanadium, zinc, germanium, molybdenum, indium, antimony, bismuth, barium, tungsten, palladium, strontium, cerium, niobium, zirconium, scandium, gallium, and yttrium.
  • a second aspect of the present application provides a method for preparing a positive electrode material, comprising the following steps:
  • the positive electrode material comprises a core of a nickel cobalt lithium manganese oxide composite and a coating structure formed on at least a portion of the surface of the core, wherein the coating structure comprises a first coating layer, a second coating layer, a third coating layer, a fourth coating layer and a fifth coating layer which are stacked in sequence from the core in a radial direction, wherein the first coating layer is located in the first layer outside the core, wherein the first coating layer comprises an oxide of the first metal, the second coating layer comprises lithium nickel cobalt manganese oxide doped with the second doped metal, the third coating layer comprises an oxide of the third metal, the fourth coating layer comprises lithium nickel cobalt manganese oxide doped with the third doped metal, and the fifth coating layer comprises the At least one of the oxide, fluoride and phosphate of the fifth metal, and the first metal, the second doped metal, the third metal, the third doped metal and the fifth metal are of the same or different types.
  • the first step (S10) is to provide a nickel-cobalt-manganese complex precursor core;
  • the second step (S20) is to wet-coat the surface of the nickel-cobalt-manganese complex precursor core with a hydroxide coating layer of the first metal to obtain a first coating.
  • the third step (S30) is based on the second step, using the first coating generated in the second step as a seed, and then continuing to nucleate and grow into larger precursor particles, and coating the surface of the first coating to form a nickel-cobalt-manganese hydroxide layer doped with a second doped metal to obtain a second coating.
  • the fourth step (S40) continues to wet-coat the surface of the second coating with a hydroxide coating layer of the third metal to obtain a third coating.
  • the fifth step (S50) is to use the third coating coated with two layers of hydroxide coating layers generated in the fourth step as a seed, continue to grow into a precursor of larger particles, and coat the surface of the third coating to form a nickel-cobalt-manganese hydroxide layer doped with a third doped metal to obtain a fourth coating.
  • the sixth step (S60) is to mix and calcine the fourth coating with the lithium source and other metal ions, so that the lithium source diffuses into all structures in the nickel-cobalt-manganese complex to form a nickel-cobalt-manganese oxide lithium complex, and at the same time, the hydroxide coating layer of the first metal and the hydroxide coating layer of the third metal are respectively decomposed into the oxide coating layer of the first metal and the oxide coating layer of the third metal; and the nickel-cobalt-manganese hydroxide layer doped with the second doped metal and the nickel-cobalt-manganese hydroxide layer doped with the third doped metal are respectively reacted to form a nickel-cobalt-manganese oxide layer doped with the second doped metal and a nickel-cobalt-manganese oxide layer doped with the third doped metal, so as to obtain a nickel-cobalt-manganese oxide lithium complex containing a coating layer.
  • the present application adopts two wet coating processes and two continuous nucleation growth processes to form a coating structure consisting of a plurality of coating layers on the surface of the lithium nickel cobalt manganese oxide.
  • the coating structure can effectively alleviate the crystal structure changes of the lithium nickel cobalt manganese oxide positive electrode material during the cycle and high temperature process, reduce the cracks in the crystal and the changes in the unit cell parameters, stabilize the crystal structure stability of the positive electrode material during use, and improve the cycle performance of the positive electrode material and the secondary battery.
  • step S10 further includes the following steps:
  • NixCoyMnzMj (OH) 2 (x+y+z+j 2, M is the first doping metal, with an average valence of +2).
  • a salt solution of nickel ions, cobalt ions, manganese ions and ions of the first doping metal can be placed in a continuous stirred reactor (CSTR), a protective gas is introduced, and the pH value and temperature of the solution are adjusted with a first alkali solution to prepare a doped nickel-cobalt-manganese complex precursor core.
  • CSTR continuous stirred reactor
  • the type of the first doping metal is not particularly limited and can be selected according to actual needs.
  • the first doping metal can include one or more of sodium, potassium, calcium, magnesium, aluminum, copper, indium, antimony, bismuth, barium, tungsten, palladium, strontium, cerium, niobium, scandium, gallium, silver, vanadium, zinc, germanium and molybdenum.
  • nickel ions, cobalt ions, manganese ions and ions of the first doping metal are provided in the form of salts.
  • the type of salt used is not particularly limited and can be selected according to actual needs. For example, it can include at least one of the sulfates, acetates, chlorides and nitrates of the corresponding metals.
  • the first alkaline environment includes a first alkali solution.
  • the type of the first alkali solution is not specifically limited and can be selected according to actual needs.
  • it can include at least one of solutions of sodium hydroxide, potassium hydroxide, ammonium bicarbonate and ammonium carbonate.
  • the pH value of the first alkaline environment is 10-14.
  • the molar ratio of nickel ions, cobalt ions, manganese ions, and ions of the first doping metal is (0.3-1):(0.01-0.5):(0.1-0.5):(0.01-0.3).
  • the reaction temperature in step S10 is 30°C to 80°C, preferably 40°C to 70°C; the reaction time is 1h to 10h, preferably 2h to 9h; and the stirring speed of the reactor is 500rpm to 3000rpm.
  • the median particle size of the nickel-cobalt-manganese composite precursor obtained in step S10 is 0.1 ⁇ m to 10 ⁇ m.
  • the doping of the first doping metal ions in step S10 is beneficial to improving the conductivity and ion mobility of the nickel-cobalt-manganese composite, thereby improving its cycle performance.
  • step S20 further includes the following steps:
  • the solution in the continuous stirring reactor after the reaction in step S100 can be filtered, and a salt solution of the ions of the first metal of the nucleating agent is added to the reactor, the pH value of the solution is adjusted to place the solution in a second alkaline environment, and the reaction temperature and reaction time are controlled to wet-coat the surface of the inner core of the nickel-cobalt-manganese composite precursor with a hydroxide coating layer of the first metal to obtain a first coating.
  • the type of the first metal is not particularly limited and can be selected according to actual needs.
  • the first metal can include one or more of calcium, iron, copper, aluminum, zirconium, magnesium, indium, antimony, bismuth, barium, tungsten, palladium, strontium, cerium, niobium, scandium, gallium, silver, vanadium, zinc, germanium and molybdenum.
  • the ions of the first metal are provided in the form of salts.
  • the type of salt used is not specifically limited and can be selected according to actual needs.
  • the salt solution can include at least one of sulfates, acetates, chlorides and nitrates of the corresponding metal.
  • the pH value of the second alkaline environment is 10-14.
  • the reaction temperature in step S200 is 20°C to 40°C, preferably 25°C to 35°C; the reaction time is 1h to 5h, preferably 2h to 4h; and the stirring speed of the reactor is 100rpm to 3000rpm.
  • the thickness of the first metal hydroxide coating layer formed in step S200 is 0.01 ⁇ m to 2 ⁇ m.
  • step S30 further includes the following steps:
  • the solution in the continuously stirred reactor after the reaction in step S200 can be filtered, and a salt solution of nickel ions, cobalt ions, manganese ions and ions of the second doping metal can be added to the reactor, and a protective gas can be introduced.
  • the pH value of the solution is adjusted using a second alkali solution, and the reaction temperature and reaction time are controlled to coat the surface of the first coating with a nickel-cobalt-manganese hydroxide layer doped with the second doping metal to obtain a second coating.
  • the type of the second doping metal is not particularly limited and can be selected according to actual needs.
  • the second doping metal can include one or more of sodium, potassium, calcium, magnesium, aluminum, copper, indium, antimony, bismuth, barium, tungsten, palladium, strontium, cerium, niobium, scandium, gallium, silver, vanadium, zinc, germanium and molybdenum.
  • the ions of the second doping metal are provided in the form of salt.
  • the type of salt used is not specifically limited and can be selected according to actual needs.
  • the salt solution can include at least one of sulfates, acetates, chlorides and nitrates of the corresponding metal.
  • the third alkaline environment includes a second alkaline solution.
  • the type of the second alkaline solution is not specifically limited and can be selected according to actual needs.
  • it can include at least one of solutions of sodium hydroxide, potassium hydroxide, ammonium bicarbonate and ammonium carbonate.
  • the pH value of the third alkaline environment is 10-14.
  • the molar ratio of nickel ions, cobalt ions, manganese ions, and ions of the second doping metal is (0.3-1):(0.01-0.5):(0.1-0.5):(0.01-0.3).
  • the reaction temperature in step S30 is 30°C to 80°C, preferably 35°C to 75°C; the reaction time is 1h to 10h, preferably 2h to 9h; and the stirring speed of the reactor is 100rpm to 2000rpm.
  • step S30 the first coating generated in the second step is used as a seed, and by controlling the reaction time and temperature, the first coating continues to nucleate and grow into larger precursor particles, and forms a second metal-doped nickel-cobalt-manganese hydroxide layer on the surface of the first coating to obtain a second coating.
  • step S40 further includes the following steps:
  • the solution in the continuous stirring reactor after the reaction in step S300 is filtered, and a salt solution of the ions of the third metal as the nucleating agent is added to the reactor, the pH value of the solution is adjusted so that the solution is in a fourth alkaline environment, and the reaction temperature and reaction time are controlled to form a hydroxide coating layer of the third metal on the surface of the second coating.
  • the type of the third metal is not particularly limited and can be selected according to actual needs.
  • the third metal can include one or more of calcium, iron, copper, aluminum, zirconium, magnesium, indium, antimony, bismuth, barium, tungsten, palladium, strontium, cerium, niobium, scandium, gallium, silver, vanadium, zinc, germanium and molybdenum.
  • the ions of the third metal are provided in the form of a salt.
  • the type of salt used is not specifically limited and can be selected according to actual needs.
  • the salt solution can include at least one of the sulfate, acetate, chloride and nitrate of the corresponding metal.
  • the pH value of the fourth alkaline environment is 10-14.
  • the reaction temperature in step S400 is 20°C to 40°C, preferably 25°C to 35°C; the reaction time is 1h to 5h, preferably 2h to 4h; and the stirring speed of the reactor is 100rpm to 3000rpm.
  • the thickness of the first metal hydroxide coating layer formed in step S400 is 0.01 ⁇ m to 2 ⁇ m.
  • Step S40 continues to wet-coat the surface of the second coating with a hydroxide coating layer of a third metal to obtain a third coating.
  • step S50 further includes the following steps:
  • the solution in the continuously stirred reactor after the reaction in step S400 can be filtered, and a salt solution of nickel ions, cobalt ions, manganese ions and ions of the third doping metal can be added to the reactor, and a protective gas can be introduced.
  • the pH value of the solution is adjusted using a third alkali solution, and the reaction temperature and reaction time are controlled to coat the surface of the third coating with a nickel-cobalt-manganese hydroxide layer doped with the third doping metal to obtain a fourth coating.
  • the type of the third doping metal is not particularly limited and can be selected according to actual needs.
  • the third doping metal can include one or more of sodium, potassium, calcium, magnesium, aluminum, copper, indium, antimony, bismuth, barium, tungsten, palladium, strontium, cerium, niobium, scandium, gallium, silver, vanadium, zinc, germanium and molybdenum.
  • the ions of the third doping metal are provided in the form of salt.
  • the type of salt used is not specifically limited and can be selected according to actual needs.
  • the salt solution can include at least one of sulfates, acetates, chlorides and nitrates of the corresponding metal.
  • the fifth alkaline environment includes a third alkaline solution.
  • the type of the third alkaline solution is not specifically limited and can be selected according to actual needs.
  • it can include at least one of solutions of sodium hydroxide, potassium hydroxide, ammonium bicarbonate and ammonium carbonate.
  • the pH value of the fifth alkaline environment is 10-14.
  • the molar ratio of nickel ions, cobalt ions, manganese ions, and ions of the third doping metal is (0.3-1):(0.01-0.5):(0.1-0.5):(0.01-0.3).
  • the reaction temperature in step S30 is 30°C to 80°C, preferably 35°C to 75°C; the reaction time is 3h to 20h, preferably 5h to 15h; and the stirring speed of the reactor is 100rpm to 2000rpm.
  • step S50 the third coating generated in the fourth step is used as a seed crystal, and by controlling the reaction time and temperature, the third coating continues to nucleate and grow into larger precursor particles, and forms a third metal-doped nickel-cobalt-manganese hydroxide layer on the surface of the third coating to obtain a fourth coating.
  • step S60 further includes the following steps:
  • the solution in the continuously stirred reactor after the reaction in step S500 can be filtered, and a lithium source and ions of a fourth doping metal can be added to the reactor to obtain a doped fourth coating; and then the doped fourth coating can be calcined to diffuse the lithium element and the fourth doping metal into the fourth coating.
  • the type of lithium source is not specifically limited and can be selected according to actual needs.
  • the lithium source can include one or more of lithium carbonate, lithium hydroxide, lithium acetate, lithium oxide and lithium nitride.
  • the type of the fourth doping metal is not specifically limited and can be selected according to actual needs.
  • the fourth doping metal includes one or more of sodium, potassium, copper, silver, magnesium, aluminum, titanium, vanadium, zinc, germanium, molybdenum, indium, antimony, bismuth, barium, tungsten, palladium, strontium, cerium, niobium, zirconium, scandium, gallium and yttrium.
  • the ions of the fourth doping metal may be selected from at least one of oxides, fluorides, phosphates, hydrogen phosphates, dihydrogen phosphates, and acetates of the ions of the fourth doping metal.
  • the molar ratio of the fourth coating to the lithium source and the fourth doping metal ion is 1:(1-2):(0.01-0.3).
  • the calcination treatment in step S60 is performed at a temperature of 400° C. to 1500° C., preferably 500° C. to 1400° C., and for a time of 5 h to 40 h, preferably 10 h to 35 h.
  • the median particle size of the nickel-cobalt-lithium manganese oxide composite containing the coating layer is 5 ⁇ m to 30 ⁇ m.
  • Step S60 Mix and calcine the fourth coating with the lithium source to diffuse the lithium element and the fourth doping metal into the nickel-cobalt-manganese composite to form a nickel-cobalt-manganese oxide lithium composite.
  • the hydroxide coating layer of the first metal and the hydroxide coating layer of the third metal formed in the previous step are respectively decomposed into the oxide coating layer of the first metal and the oxide coating layer of the third metal to inhibit the volume change of the positive electrode material during the charge and discharge process; and the nickel-cobalt-manganese hydroxide layer doped with the second doping metal and the nickel-cobalt-manganese hydroxide layer doped with the third doping metal are respectively reacted to form a second doping metal doped nickel-cobalt-manganese oxide layer and a third doping metal doped nickel-cobalt-manganese oxide layer to provide the main active material components to obtain a nickel-cobalt-manganese oxide lithium
  • step S70 further includes the following steps:
  • the nickel cobalt manganese oxide composite containing the coating layer can be formed into a suspension in a solution, the coating agent containing the fifth metal is dissolved in the suspension, the pH value of the solution is adjusted, and a hydroxide precipitation layer of the fifth metal is formed on the surface of the nickel cobalt manganese oxide composite containing the coating layer, and then calcined to decompose the hydroxide of the fifth metal into an oxide layer of the fifth metal to form a fifth coating layer.
  • the nickel cobalt manganese oxide composite containing the coating layer and the coating agent containing the fifth metal can be uniformly mixed and calcined to form a fifth coating layer on the surface of the nickel cobalt manganese oxide composite containing the coating layer.
  • the type of the fifth metal is not specifically limited and can be selected according to actual needs.
  • the fifth metal can include one or more of sodium, potassium, copper, silver, magnesium, aluminum, titanium, vanadium, zinc, germanium, molybdenum, indium, antimony, bismuth, barium, tungsten, palladium, strontium, cerium, niobium, zirconium, scandium, gallium and yttrium.
  • the molar ratio of the lithium nickel cobalt manganese oxide composite containing the coating layer to the coating agent containing the fifth metal is 1:(0.001-0.3).
  • the capping agent containing the fifth metal may be one or more of an oxide, a fluoride, and a phosphate of the fifth metal.
  • the temperature of the fifth coating treatment in step S70 is 300°C to 1000°C, that is, the temperature of the above calcination is 300°C to 1000°C, preferably 350°C to 950°C.
  • a coating agent containing a fifth metal is used to further coat the surface of the nickel cobalt manganese oxide composite containing a coating layer.
  • the formed fifth coating layer can prevent the infiltration of the electrolyte, thereby effectively preventing the side reaction between the electrolyte and the nickel cobalt manganese oxide from causing powdering, capacity decay and gas production of the battery, thereby improving the gram capacity, cycle performance, high temperature performance and safety performance of the positive electrode material.
  • the above-mentioned reaction steps of the present application can be carried out in a continuous reactor, wherein the continuous reactor adopts a bottom filter device, and the bottom filter device can filter the solution in each reaction step, thereby achieving the product obtained in the previous step without the need for a reaction.
  • the reactor can then be used as a reactant to enter the next step to continuously participate in the reaction, which is beneficial to improving the stability of the product and production efficiency.
  • a third aspect of the embodiments of the present application provides a positive electrode plate, comprising the positive electrode material provided in the first aspect of the present application or the positive electrode material prepared by the method provided in the second aspect of the present application.
  • the positive electrode plate includes a positive electrode current collector and a positive electrode film layer disposed on at least one surface of the positive electrode current collector, and the positive electrode film layer includes the positive electrode material of the second aspect of the present application.
  • a fourth aspect of the embodiments of the present application provides a secondary battery, comprising the positive electrode plate provided in the third aspect of the present application.
  • the type of secondary battery is not specifically limited, and may include any battery in which an electrochemical reaction occurs to convert chemical energy into electrical energy, for example, a lithium ion battery or a sodium ion battery.
  • the secondary battery further includes a negative electrode sheet, an electrolyte and a separator.
  • active ions are embedded and extracted back and forth between the positive electrode sheet and the negative electrode sheet.
  • the electrolyte plays the role of conducting ions between the positive electrode sheet and the negative electrode sheet.
  • the separator is arranged between the positive electrode sheet and the negative electrode sheet, mainly to prevent the positive and negative electrodes from short-circuiting, while allowing ions to pass through.
  • the fifth aspect of the embodiments of the present application provides an electronic device, comprising the secondary battery provided in the fourth aspect of the present application, wherein the secondary battery can be used as a power source in the electronic device.
  • Nickel sulfate, cobalt sulfate, manganese sulfate, aluminum sulfate and zinc sulfate were added to deionized water to prepare a mixed salt solution (1.6 mol/L, nickel sulfate, cobalt sulfate, manganese sulfate, aluminum sulfate and zinc sulfate according to the metal ion stoichiometric molar ratio of 98:1:1:0.01:0.01), and the mixed solution was pumped into a reactor in parallel with a certain concentration of NaOH solution (5 mol/L) and a certain concentration of ammonia solution (20 wt%), the reactor was filled with nitrogen, the temperature in the reactor was controlled at 50° C., the pH value in the reactor was controlled at 11.2-11.4, the stirring device in the reactor was started, and the reaction was continued for 4 hours to obtain a precursor core with a D50 of 3.8 ⁇ m.
  • a mixed salt solution 1.6 mol/
  • step (1) The reaction solution of step (1) is filtered under pressure through the filter at the bottom of the reactor, and the product precursor core obtained in step (1) is retained on the filter at the bottom of the reactor.
  • a 2 mol/L magnesium sulfate solution is added to the reactor, and the reactor is stirred to form a suspension.
  • a 2 mol/L NaOH solution is added to adjust the pH value of the solution to 13 and the temperature to 30°C to prepare a precursor core coated with magnesium hydroxide, i.e., the first coating.
  • step (3) The reaction solution of step (2) was filtered under pressure through a filter at the bottom of the reactor, nickel sulfate, cobalt sulfate, manganese sulfate, aluminum sulfate and zinc sulfate were added to deionized water to prepare a mixed salt solution (1.6 mol/L, nickel sulfate, cobalt sulfate, manganese sulfate, aluminum sulfate and zinc sulfate were prepared in a metal ion stoichiometric molar ratio of 90:5:5:0.02:0.03), the mixed solution and a certain concentration of NaOH solution (5 mol/L) and a certain concentration of ammonia solution (20 wt%) were pumped into the reactor in parallel, the reactor was filled with nitrogen, the temperature in the reactor was controlled to 50° C., the pH value in the reactor was controlled to 13.0-13.5, the stirring device in the reactor was started, and the reaction was continued for 5 hours to obtain a layered
  • step (3) The reaction solution of step (3) is pressure filtered through the filter screen at the bottom of the reactor, 2 mol/L aluminum sulfate solution is added to the reactor, the reactor is stirred, and the solution becomes a suspension. 2 mol/L NaOH solution is added to adjust the pH value of the solution to 13 and the temperature to 30°C to prepare a layered structure precursor coated with aluminum hydroxide, i.e., the third coating.
  • step (4) The reaction solution of step (4) was filtered under pressure through a filter at the bottom of the reactor, nickel sulfate, cobalt sulfate, manganese sulfate, aluminum sulfate and zinc sulfate were added to deionized water to prepare a mixed salt solution (2.0 mol/L, nickel sulfate, cobalt sulfate, manganese sulfate, aluminum sulfate and magnesium sulfate according to the metal ion stoichiometric molar ratio of 80:1:1:0.05:0.02), and the mixed solution was mixed with a certain concentration of NaOH solution (5 mol/L) and a certain concentration of An ammonia solution (20wt%) was pumped into the reactor in parallel, the reactor was filled with nitrogen, the temperature in the reactor was controlled to be 50°C, the pH value in the reactor was controlled to be between 13.0 and 13.5, the stirring device in the reactor was started, and the reaction was continued for 10 hours to
  • the multilayer structure precursor prepared in step (5) and lithium hydroxide monohydrate are uniformly mixed at a high speed in a high-speed mixer according to a stoichiometric molar ratio of 1:1.10, and the mixture is placed in a muffle furnace for calcination under an oxygen atmosphere.
  • the temperature of the muffle furnace is increased from 25°C to 500°C at a heating rate of 5°C/min, and the temperature is kept at this temperature for 5 hours.
  • the temperature is then increased from 400°C to 930°C at a rate of 5°C/min, and the temperature is kept at this temperature for 15 hours.
  • the mixture is cooled to room temperature.
  • the mixture is crushed by jaw crusher, roller, mechanical crushing and sieved through a 400-mesh sieve to obtain a multilayer structure of lithium nickel cobalt manganese oxide with a D50 of 11.83 ⁇ m, i.e., the fifth coating.
  • the temperature is increased from 25°C to 550°C in a muffle furnace at a heating rate of 5°C/min, and the temperature is kept at this temperature for 8 hours, and then cooled to room temperature; the mixture is crushed by jaw crusher, roller, mechanical crushing and sieved through a 400-mesh sieve to obtain a coated multilayer structure lithium nickel cobalt manganese oxide positive electrode material with a D50 of 12.43 ⁇ m, i.e., the final positive electrode material is obtained.
  • Example 2 The preparation method of Example 2 is similar to that of Example 1, except that:
  • Step (1) nickel sulfate, cobalt sulfate, manganese sulfate, aluminum sulfate and zinc sulfate are added to deionized water to prepare a mixed salt solution (2.0 mol/L, nickel sulfate, cobalt sulfate, manganese sulfate, magnesium sulfate and aluminum sulfate according to the metal ion stoichiometric molar ratio of 90:5:5:0.01:0.01).
  • Step (2) Add 2 mol/L copper sulfate solution into the reaction kettle.
  • Step (3) nickel sulfate, cobalt sulfate, manganese sulfate, aluminum sulfate and zinc sulfate are used to prepare a mixed salt solution (1.6 mol/L, nickel sulfate, cobalt sulfate, manganese sulfate, aluminum sulfate and zinc sulfate according to the metal ion stoichiometric molar ratio of 85:5:15:0.03:0.03).
  • Step (4) Add 2 mol/L aluminum sulfate and 2 mol/L magnesium sulfate solution into the reactor.
  • the nickel sulfate, cobalt sulfate, manganese sulfate, aluminum sulfate and zinc sulfate in step (5) are used to prepare a mixed salt solution (2.0 mol/L, nickel sulfate, cobalt sulfate, manganese sulfate, aluminum sulfate and magnesium sulfate are in a metal ion stoichiometric molar ratio of 60:20:20:0.05:0.05).
  • the multilayer structure precursor prepared in step (6) and lithium hydroxide monohydrate are uniformly mixed at high speed in a high-speed mixer according to a stoichiometric molar ratio of 1:1.05.
  • Step (7) The multilayer structure of lithium nickel cobalt manganese oxide and aluminum oxide, titanium oxide and magnesium oxide are mixed uniformly in a high-speed mixer according to a stoichiometric molar ratio of 1:0.03:0.05:0.03.
  • Example 3 The preparation method of Example 3 is similar to that of Example 1, except that:
  • Step (2) Add 1.5 mol/L copper sulfate solution and 1.5 mol/L cobalt sulfate solution into the reaction kettle.
  • Step (4) Add 2 mol/L aluminum acetate and 2 mol/L magnesium acetate solution into the reaction kettle.
  • Example 4 The preparation method of Example 4 is similar to that of Example 1, except that:
  • the multilayer structure precursor prepared in step (6) and lithium hydroxide monohydrate are uniformly mixed at a high speed in a high-speed mixer according to a stoichiometric molar ratio of 1:1.03, and the mixture is placed in a muffle furnace for calcination under an oxygen atmosphere.
  • the muffle furnace is heated at a rate of 5°C/min, from 25°C to 500°C, and kept warm for 5 hours, and then heated from 400°C to 900°C at a rate of 5°C/min.
  • the multilayer structure lithium nickel cobalt manganese oxide prepared in step (7) and niobium oxide, zirconium oxide, and yttrium oxide are mixed evenly in a high-speed stirrer according to a stoichiometric molar ratio of 1:0.03:0.05:0.03, calcined in an oxygen atmosphere, heated at a muffle furnace at a rate of 5°C/min, from 25°C to 550°C, kept warm for 8 hours, and cooled to room temperature.
  • the multilayer structure lithium nickel cobalt manganese oxide with a D50 of 13.58 ⁇ m is prepared by jaw crushing, roller crushing, mechanical crushing, and 400 mesh sieve.
  • Example 5 The preparation method of Example 5 is similar to that of Example 1, except that:
  • Step (1) nickel sulfate, cobalt sulfate, manganese sulfate, aluminum sulfate and zinc sulfate are added to deionized water to prepare a mixed salt solution (2.0 mol/L, nickel sulfate, cobalt sulfate, manganese sulfate, aluminum sulfate according to the metal ion stoichiometric molar ratio of 98:1:1:0.03).
  • the nickel sulfate, cobalt sulfate, manganese sulfate, aluminum sulfate and magnesium sulfate in step (5) are used to prepare a mixed salt solution (2.0 mol/L, with the stoichiometric molar ratio of the metal ions of nickel sulfate, cobalt sulfate, manganese sulfate, aluminum sulfate and magnesium sulfate being 80:10:10:0.03:0.03).
  • Example 6 The preparation method of Example 6 is similar to that of Example 1, except that:
  • Step (2) Add 3 mol/L aluminum sulfate solution and 1.5 mol/L cobalt sulfate solution into the reaction kettle.
  • Step (7) The multilayer structure of lithium nickel cobalt manganese oxide and titanium oxide, zirconium oxide and magnesium oxide are mixed uniformly in a high-speed mixer according to a stoichiometric molar ratio of 1:0.04:0.03:0.02.
  • Example 7 The preparation method of Example 7 is similar to that of Example 1, except that:
  • Step (4) Add 3 mol/L cobalt chloride and 2 mol/L copper chloride solution into the reaction kettle.
  • Step (6) The multilayer structure precursor and lithium hydroxide monohydrate are uniformly mixed at high speed in a high-speed mixer according to a stoichiometric molar ratio of 1:1.04.
  • Step (7) The multilayer structure of lithium nickel cobalt manganese oxide and zirconium oxide, yttrium oxide and titanium oxide in a stoichiometric molar ratio of 1:0.03:0.03:0.04 are mixed evenly in a high-speed mixer.
  • Example 8 The preparation method of Example 8 is similar to that of Example 1, except that:
  • Step (1) nickel sulfate, cobalt sulfate, manganese sulfate, aluminum sulfate and zinc sulfate are added to deionized water to prepare a mixed salt solution (3.0 mol/L, nickel sulfate, cobalt sulfate, manganese sulfate, aluminum sulfate according to the metal ion stoichiometric molar ratio of 95:2:3:0.05), the temperature is 60° C., and the pH value in the reactor is controlled to be 11.0-11.8.
  • Example 9 The preparation method of Example 9 is similar to that of Example 1, except that:
  • Step (1) nickel sulfate, cobalt sulfate, manganese sulfate, aluminum sulfate and zinc sulfate are added to deionized water to prepare a mixed salt solution (3.0 mol/L, nickel sulfate, cobalt sulfate and manganese sulfate are in a metal ion stoichiometric molar ratio of 90:5:5).
  • Step (7) The multilayer structure of lithium nickel cobalt manganese oxide and magnesium fluoride, zirconium oxide and titanium oxide are mixed uniformly in a high-speed mixer at a stoichiometric molar ratio of 1:0.03:0.03:0.03.
  • Example 10 The preparation method of Example 10 is similar to that of Example 1, except that:
  • Step (7) The multilayer structure of lithium nickel cobalt manganese oxide, lithium phosphate, magnesium fluoride and titanium oxide are mixed uniformly in a high-speed stirrer according to a stoichiometric molar ratio of 1:0.05:0.03:0.01:0.01.
  • Comparative Example 1 is a commercial nickel cobalt manganese oxide lithium positive electrode material Li(Ni 0.8 Co 0.1 Mn 0.1 )O 2 .
  • Comparative Example 2 The preparation method of Comparative Example 2 is similar to the preparation method of Example 1, except that step (2) and step (4) are not included.
  • test conditions or test standards for each performance test item are as follows:
  • the surface morphology of the materials was measured using a JSM-6510 scanning electron microscope from JEOL, Japan, and an EV018 scanning electron microscope from Carl Zeiss, Germany.
  • the X-ray energy scattering (EDS) spectra and elemental distribution maps were obtained using an Oxford X-MAX 20 spectrometer.
  • the mass percentage of nickel element is determined by gravimetric method; the mass percentage of cobalt element is determined by potentiometric titration method; the mass percentage of manganese element is determined by titration method; the mass percentage of other metal elements is determined by ICP method.
  • the positive electrode material, conductive agent Super P and binder PVDF (HSV900) of the embodiment of the present application were weighed at a mass ratio of 96:2:2; the negative electrode active material graphite, conductive agent Super P and binder PVDF (HSV900) were weighed at a mass ratio of 96:2:2; an appropriate amount of N-methylpyrrolidone was added as a solvent, and stirred with a magnetic stirrer for 15 hours under argon protection in a glove box to prepare the slurry required for the thin film battery.
  • the coating machine is the MSK-AFA-III automatic film coating and drying machine of Shenzhen Kejing Zhida Technology Co., Ltd., with a coating gap of 25 microns and a speed of 5 cm/min.
  • the slurry is evenly coated on a 9-micron thick, 99.8% pure smooth copper foil produced by Meixian Jinxiang Copper Foil Co., Ltd., and vacuum dried at 120°C for 12 hours, and then punched into an electrode sheet with a diameter of about 16 mm in the Shenzhen Kejing MSK-T06 button battery punching machine.
  • the battery assembly is carried out in a German Braun (Mbraun, Unilab) glove box filled with 99.9% high-purity argon.
  • the diaphragm was a 16-micron thick American ENTEK LP16 PE diaphragm, the electrolyte was DMC:EMC (60:40, mass ratio), 2% VC of the total mass of DMC and EMC, and 1.3 mol/L LiPF 6 were added.
  • the thin film battery (10mAh) prepared above was charged to 4.5V at a constant current of 0.5C at 25°C, 45°C and 60°C, then charged to a current of 0.7C at a constant voltage, left to stand for 5 minutes, and then discharged to 2.8V at a constant current of 1C. This was one charge and discharge cycle, and the discharge capacity at this time was tested and recorded.
  • the lithium-ion battery was cycled 120 times according to the above charge and discharge process, and the discharge capacity of the 100th cycle was tested and recorded. The test data is recorded in Table 1 below.

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  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Composite Materials (AREA)
  • Inorganic Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Battery Electrode And Active Subsutance (AREA)

Abstract

La présente invention concerne : un matériau d'électrode positive, son procédé de préparation, une feuille d'électrode positive, une batterie secondaire et un dispositif électronique. Le matériau d'électrode positive comprend un noyau interne formé par un composite d'oxyde de lithium-nickel-manganèse-cobalt, et une structure de revêtement formée sur au moins une partie de la surface du noyau interne. La structure de revêtement comprend une première couche de revêtement, une deuxième couche de revêtement, une troisième couche de revêtement, une quatrième couche de revêtement et une cinquième couche de revêtement, qui sont empilées séquentiellement dans la direction radiale à partir du noyau interne vers l'extérieur. La première couche de revêtement comprend un oxyde d'un premier métal, la deuxième couche de revêtement comprend de l'oxyde de lithium-nickel-manganèse-cobalt, la troisième couche de revêtement comprend un oxyde d'un troisième métal, la quatrième couche de revêtement comprend de l'oxyde de lithium-nickel-manganèse-cobalt, et la cinquième couche de revêtement comprend au moins l'un d'un oxyde, d'un fluorure et d'un phosphate d'un cinquième métal, les types du premier métal, du troisième métal et du cinquième métal étant identiques ou différents. Le matériau d'électrode positive fourni par la présente invention peut améliorer les performances à haute température et de cycle de la batterie secondaire.
PCT/CN2023/114243 2022-09-27 2023-08-22 Matériau d'électrode positive, son procédé de préparation, feuille d'électrode positive, batterie secondaire et dispositif électronique WO2024066809A1 (fr)

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Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2007018795A (ja) * 2005-07-06 2007-01-25 Sony Corp 正極活物質およびその製造方法、並びに電池
WO2013053318A1 (fr) * 2011-10-11 2013-04-18 上海中兴派能能源科技有限公司 Matériau ternaire composite multicouche, son précurseur et procédé de préparation pour les deux
CN109786713A (zh) * 2019-01-25 2019-05-21 清远佳致新材料研究院有限公司 三元正极材料前驱体及其制备方法、三元正极材料、正极、锂离子电池及其应用
CN111370653A (zh) * 2018-12-25 2020-07-03 深圳市比亚迪锂电池有限公司 一种正极材料前驱体及其制备方法、正极材料和电池
CN114068900A (zh) * 2021-11-15 2022-02-18 天津巴莫科技有限责任公司 一种自组装核壳结构正极材料的制备方法和应用
CN115548298A (zh) * 2022-09-27 2022-12-30 天津巴莫科技有限责任公司 正极材料及其制备方法、正极极片、二次电池和电子设备

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2007018795A (ja) * 2005-07-06 2007-01-25 Sony Corp 正極活物質およびその製造方法、並びに電池
WO2013053318A1 (fr) * 2011-10-11 2013-04-18 上海中兴派能能源科技有限公司 Matériau ternaire composite multicouche, son précurseur et procédé de préparation pour les deux
CN111370653A (zh) * 2018-12-25 2020-07-03 深圳市比亚迪锂电池有限公司 一种正极材料前驱体及其制备方法、正极材料和电池
CN109786713A (zh) * 2019-01-25 2019-05-21 清远佳致新材料研究院有限公司 三元正极材料前驱体及其制备方法、三元正极材料、正极、锂离子电池及其应用
CN114068900A (zh) * 2021-11-15 2022-02-18 天津巴莫科技有限责任公司 一种自组装核壳结构正极材料的制备方法和应用
CN115548298A (zh) * 2022-09-27 2022-12-30 天津巴莫科技有限责任公司 正极材料及其制备方法、正极极片、二次电池和电子设备

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