WO2023236068A1 - 正极活性材料及其制备方法、极片、二次电池及用电装置 - Google Patents

正极活性材料及其制备方法、极片、二次电池及用电装置 Download PDF

Info

Publication number
WO2023236068A1
WO2023236068A1 PCT/CN2022/097507 CN2022097507W WO2023236068A1 WO 2023236068 A1 WO2023236068 A1 WO 2023236068A1 CN 2022097507 W CN2022097507 W CN 2022097507W WO 2023236068 A1 WO2023236068 A1 WO 2023236068A1
Authority
WO
WIPO (PCT)
Prior art keywords
lithium
active material
ion conductor
coating layer
rich manganese
Prior art date
Application number
PCT/CN2022/097507
Other languages
English (en)
French (fr)
Inventor
赵栋
吴奇
沈重亨
王帮润
陈强
范敬鹏
柳娜
Original Assignee
宁德时代新能源科技股份有限公司
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 宁德时代新能源科技股份有限公司 filed Critical 宁德时代新能源科技股份有限公司
Priority to CN202280062469.0A priority Critical patent/CN117941101A/zh
Priority to JP2024503681A priority patent/JP2024527841A/ja
Priority to KR1020247001796A priority patent/KR20240023133A/ko
Priority to PCT/CN2022/097507 priority patent/WO2023236068A1/zh
Priority to EP22942944.4A priority patent/EP4333121A4/en
Publication of WO2023236068A1 publication Critical patent/WO2023236068A1/zh
Priority to US18/412,601 priority patent/US20240199441A1/en

Links

Images

Classifications

    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
    • C01G53/00—Compounds of nickel
    • C01G53/40—Nickelates
    • C01G53/42—Nickelates containing alkali metals, e.g. LiNiO2
    • C01G53/44—Nickelates containing alkali metals, e.g. LiNiO2 containing manganese
    • C01G53/50—Nickelates containing alkali metals, e.g. LiNiO2 containing manganese of the type [MnO2]n-, e.g. Li(NixMn1-x)O2, Li(MyNixMn1-x-y)O2
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/052—Li-accumulators
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/052—Li-accumulators
    • H01M10/0525—Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
    • 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
    • H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
    • H01M4/139—Processes of manufacture
    • H01M4/1391—Processes of manufacture of 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
    • 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
    • H01M4/36—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
    • H01M4/485—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of mixed oxides or hydroxides for inserting or intercalating light metals, e.g. LiTi2O4 or LiTi2OxFy
    • 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
    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H01M4/58—Selection of substances as active materials, active masses, active liquids of inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy; of polyanionic structures, e.g. phosphates, silicates or borates
    • H01M4/5825—Oxygenated metallic salts or polyanionic structures, e.g. borates, phosphates, silicates, olivines
    • 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
    • H01M4/62—Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2002/00—Crystal-structural characteristics
    • C01P2002/08—Intercalated structures, i.e. with atoms or molecules intercalated in their structure
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2004/00—Particle morphology
    • C01P2004/60—Particles characterised by their size
    • C01P2004/61—Micrometer sized, i.e. from 1-100 micrometer
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2004/00—Particle morphology
    • C01P2004/80—Particles consisting of a mixture of two or more inorganic phases
    • C01P2004/82—Particles consisting of a mixture of two or more inorganic phases two phases having the same anion, e.g. both oxidic phases
    • C01P2004/84—Particles consisting of a mixture of two or more inorganic phases two phases having the same anion, e.g. both oxidic phases one phase coated with the other
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2006/00—Physical properties of inorganic compounds
    • C01P2006/12—Surface area
    • 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
    • H01M2004/021—Physical characteristics, e.g. porosity, surface area
    • 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

  • This application belongs to the technical field of secondary batteries, and specifically relates to a positive active material and a preparation method thereof, a pole piece, a secondary battery and an electrical device.
  • Secondary batteries are widely used in various consumer electronics and electric vehicles due to their outstanding characteristics such as light weight, no pollution, and no memory effect.
  • lithium-rich manganese-based cathode material is a cathode material with high hopes. It has a high discharge specific capacity, almost twice that of lithium iron phosphate, and because it contains manganese, its preparation cost is relatively low. .
  • lithium-rich manganese-based cathode materials have poor first discharge efficiency, cycle performance and rate performance, which greatly hinders their practical application.
  • this application provides a cathode active material, which is applied to secondary batteries and can improve the first discharge efficiency, cycle performance and rate performance of secondary batteries.
  • a cathode active material including:
  • Core material including lithium-rich manganese-based cathode material
  • a coating layer covers the outer surface of the core material, and the coating layer contains an oxygen ion conductor and a lithium ion conductor.
  • this application at least includes the following beneficial effects:
  • the cathode active material of the present application is formed by forming the above-mentioned coating layer containing both an oxygen ion conductor and a lithium ion conductor on the outer surface of a core material containing a lithium-rich manganese-based cathode material.
  • Oxygen ion conductors and lithium ion conductors are synergistically introduced into the coating layer as the core material containing lithium-rich manganese-based cathode materials.
  • the interior of the oxygen ion conductor has a high oxygen vacancy concentration and has high oxygen adsorption and storage capabilities, which can effectively suppress
  • the release of lithium-rich manganese-based lattice oxygen can also reduce the extraction of lithium ions, thereby improving the first charge and discharge efficiency of the cathode active material.
  • the oxygen release from the crystal lattice of the lithium-rich manganese-based cathode material is suppressed, and the structural stability of the lithium-rich manganese-based cathode material is improved, which in turn can improve the cycle stability of the cathode active material.
  • a lithium ion conductor is introduced, which has high ionic conductivity, increases the transmission rate of lithium ions, and reduces the escape of lithium ions, thereby improving the capacity and rate performance of the cathode active material.
  • the oxygen ion conductor includes at least one of La 2 Mo 2 O 9 and fluorite type oxygen ion conductor.
  • the fluorite-type oxygen ion conductor includes at least one of ZrO 2 , CeO 2 and GeO 2 .
  • the lithium ion conductor includes at least one of LiLaO 2 , Li 2 MoO 4 , Li 3 PO 4 , Li 3 BO 3 and LiTaO 3 .
  • the oxygen ion conductor includes La 2 Mo 2 O 9 ; the lithium ion conductor includes LiLaO 2 and Li 2 MoO 4 .
  • the molar ratio of lanthanum atoms and molybdenum atoms in the coating layer is 1: (1.02-1.1); optionally 1: (1.02-1.05).
  • the content of molybdenum atoms in the coating layer is 300-5000 ppm; and/or,
  • the content of lanthanum atoms in the coating layer is 500-5000 ppm.
  • the content of molybdenum atoms in the coating layer is 1000-4000ppm; and/or,
  • the content of lanthanum atoms in the coating layer is 1000-3000 ppm.
  • the surface of the core material is doped with lanthanum atoms and molybdenum atoms.
  • the surface thickness of the core material doped with lanthanum atoms and molybdenum atoms is no more than 3 ⁇ m; optionally, it is no more than 2 ⁇ m.
  • the thickness of the coating layer is 0.01-4 ⁇ m.
  • the thickness of the coating layer is 0.02-1 ⁇ m.
  • the peak intensity ratio of IO 2 2- /IO 2- in the coating layer is 0.5-1; optionally, it is 0.7-0.9;
  • IO 2 2- is the peak intensity value of the oxygen vacancy at 531eV in the X-ray photoelectron spectroscopy test
  • IO 2- is the peak intensity value corresponding to the lattice oxygen at 529eV in the X-ray photoelectron spectroscopy test.
  • the molecular formula of the lithium-rich manganese-based cathode material is xLi 2 MnO 3 ⁇ (1-x)LiNi y Co z Mn a M 1-yza O 2 ,
  • M is Mg, B, Al, V, Ti, Zr, Sn At least one of Mo.
  • the particle type of the lithium-rich manganese-based cathode material is secondary particles, single crystal or quasi-single crystal; and/or,
  • the specific surface area of the lithium-rich manganese-based cathode material is ⁇ 2.0m 2 /g, optionally 0.1-1m 2 /g;
  • the Dv50 particle size of the lithium-rich manganese-based cathode material is 1-20 ⁇ m; optional 3-15 ⁇ m.
  • a second aspect of the present application provides a method for preparing the cathode active material of the first aspect of the present invention, including the following steps:
  • the coating layer is formed on the surface of the core material.
  • the oxygen ion conductor includes La 2 Mo 2 O 9
  • the lithium ion conductor includes LiLaO 2 and Li 2 MoO 4
  • the preparation method includes the following steps:
  • the lithium-rich manganese-based precursor with La 2 Mo 2 O 9 deposited in situ on the surface is mixed with a lithium salt and then calcined to obtain a positive electrode active material composite-coated with an oxygen ion conductor and a lithium ion conductor.
  • the lithium-rich manganese-based precursor is Ni b Co c Mn d M (1-bc- d) (OH) 2 ,
  • M is at least one of Mg, B, Al, V, Ti, Zr, Sn and Mo.
  • the solvent is at least one of water, ethanol, methanol and ethylene glycol; and/or,
  • the molybdenum salt is at least one of ammonium molybdate, sodium molybdate and potassium molybdate; and/or,
  • the lanthanum salt is at least one of lanthanum chloride and lanthanum nitrate; and/or,
  • the lithium salt is at least one of lithium carbonate, lithium hydroxide and lithium acetate; and/or,
  • the molar ratio of the lithium element in the lithium salt and all the metal elements in the lithium-rich manganese-based precursor with La 2 Mo 2 O 9 deposited in situ on the surface is 1: (1.1-1.8), optionally 1: (1.1-1.5); and/or,
  • the pH value of the hydrothermal reaction is 8-10; and/or,
  • the atmosphere of the calcination treatment is air; and/or,
  • the steps of the calcination treatment include: pre-calcining at 300-500°C for 2-5 hours, and then sintering at 700-900°C for 10-20 hours.
  • the third aspect of this application provides a positive electrode plate, including:
  • Positive active material layer the positive active material layer is located on the surface of the positive current collector, the components of the positive active material layer include the positive active material provided in the first aspect of the application or the positive active material provided in the second aspect of the application.
  • the positive electrode active material prepared by the preparation method.
  • a fourth aspect of the present application provides a secondary battery, including the positive electrode plate provided in the third aspect of the present application.
  • a fifth aspect of the present application provides an electrical device, including the secondary battery provided in the fourth aspect of the present application.
  • FIG. 1 is a schematic diagram of an embodiment of a secondary battery.
  • FIG. 2 is an exploded view of FIG. 1 .
  • Figure 3 is a schematic diagram of an embodiment of a battery module.
  • Figure 4 is a schematic diagram of an embodiment of a battery pack.
  • FIG. 5 is an exploded view of FIG. 4 .
  • FIG. 6 is a schematic diagram of an electrical device using a secondary battery as a power source according to an embodiment.
  • any lower limit can be combined with any upper limit to form an unexpressed range; and any lower limit can be combined with other lower limits to form an unexpressed range, and likewise any upper limit can be combined with any other upper limit to form an unexpressed range.
  • each individually disclosed point or single value may itself serve as a lower or upper limit in combination with any other point or single value or with other lower or upper limits to form a range not expressly recited.
  • Secondary batteries refer to batteries that can be recharged to activate active materials and continue to be used after the battery is discharged.
  • a secondary battery typically includes a positive electrode plate, a negative electrode plate, a separator and an electrolyte.
  • active ions are inserted and detached back and forth between the positive and negative electrodes.
  • the isolation film is arranged between the positive electrode piece and the negative electrode piece to play the role of isolation.
  • the electrolyte plays a role in conducting ions between the positive and negative electrodes.
  • the positive electrode sheet usually includes a positive current collector and a positive active material layer disposed on the positive current collector.
  • the positive active material layer includes a positive active material.
  • the positive electrode current collector can be a conventional metal foil or a composite current collector.
  • the metal material can be disposed on the polymer substrate to form a composite current collector.
  • the positive electrode current collector may be aluminum foil.
  • the lithium-rich manganese-based cathode material has a high discharge specific capacity, its first discharge efficiency, cycle performance and rate performance are poor, which greatly hinders its practical application.
  • the technicians of this application have discovered through extensive research that the lithium-rich manganese-based cathode material is prone to oxygen release problems when the lithium-rich manganese-based cathode material is charged at a high voltage of more than 4.5V in the first cycle.
  • some lithium ions in the transition metal layer It will be removed together with O 2- to form Li 2 O. This part of the crystal vacancies will be difficult to accept lithium ions in the subsequent charge and discharge process, resulting in a reduction in the first charge and discharge efficiency of the lithium-rich manganese-based cathode material.
  • the formation of a large number of oxygen vacancies inside the lithium-rich manganese-based cathode material can easily lead to the migration of transition metal ions in the lithium-rich manganese-based cathode material, causing the rearrangement of the crystal structure and causing the structural instability of the lithium-rich manganese-based cathode material. This results in poor cycle performance.
  • the rate performance of the lithium-rich manganese-based cathode is extremely poor.
  • a cathode active material which includes a core material and a coating layer.
  • the core material includes lithium-rich manganese-based cathode material.
  • the coating layer covers the outer surface of the core material, and the coating layer contains an oxygen ion conductor and a lithium ion conductor.
  • the cathode active material of the present application is formed by forming the above-mentioned coating layer containing both an oxygen ion conductor and a lithium ion conductor on the outer surface of a core material containing a lithium-rich manganese-based cathode material.
  • Oxygen ion conductors and lithium ion conductors are synergistically introduced into the coating layer as the core material containing lithium-rich manganese-based cathode materials.
  • the interior of the oxygen ion conductor has a high oxygen vacancy concentration and has high oxygen adsorption and storage capabilities, which can effectively suppress
  • the release of lithium-rich manganese-based lattice oxygen can also reduce the extraction of lithium ions, thereby improving the first charge and discharge efficiency of the cathode active material.
  • the oxygen release from the crystal lattice of the lithium-rich manganese-based cathode material is suppressed, and the structural stability of the lithium-rich manganese-based cathode material is improved, which in turn can improve the cycle stability of the cathode active material.
  • a lithium ion conductor is introduced, which has high ionic conductivity, increases the transmission rate of lithium ions, and reduces the escape of lithium ions, thereby improving the capacity and rate performance of the cathode active material.
  • the components in the positive electrode active material layer include the above-mentioned coated positive electrode active material.
  • the oxygen ion conductor includes but is not limited to: at least one of La 2 Mo 2 O 9 and fluorite-type oxygen ion conductor. Further, the fluorite-type oxygen ion conductor includes at least one of ZrO 2 , CeO 2 and GeO 2 .
  • the lithium ion conductor includes, but is not limited to, at least one of LiLaO 2 , Li 2 MoO 4 , Li 3 PO 4 , Li 3 BO 3 and LiTaO 3 .
  • the lithium ion conductor includes LiLaO 2 and Li 2 MoO 4 .
  • Using a specific combination of the two lithium ion conductors can significantly improve the ionic conductivity of the cathode material, while also effectively suppressing the ion conductivity of the lithium-rich manganese-based material. Cation mixing and Mn 3+ dissolution.
  • the oxygen ion conductor includes La 2 Mo 2 O 9 and the lithium ion conductor includes LiLaO 2 and Li 2 MoO 4 .
  • the oxygen ion conductor and the lithium ion conductor have the same elements, with this specific combination, there will be good compatibility between the two, so that the oxygen ions and the lithium ion conductor in the coating layer are more closely combined, and there is It is beneficial to improve the stability of the coating layer itself and the rapid conduction of ions.
  • the molar ratio of lanthanum atoms and molybdenum atoms in the coating layer is 1: (1.02-1.1); further preferably, it is 1: (1.02-1.05).
  • the content of molybdenum atoms in the coating layer is 300-5000ppm, optionally 1000-4000ppm. Further, the content of lanthanum atoms in the coating layer is 500-5000ppm; optionally, it is 1000-3000ppm. Controlling the content of molybdenum atoms and lanthanum atoms in the coating layer can ensure that the coating layer will not be too thick and affect the capacity of the cathode active material, thereby achieving better coating effects.
  • the surface of the core material will be doped with lanthanum atoms and molybdenum atoms.
  • the surface thickness of the core material doped with lanthanum atoms and molybdenum atoms is no more than 3 ⁇ m; optionally, it is no more than 2 ⁇ m.
  • the surface thickness of the core material doped with lanthanum atoms and molybdenum atoms is no more than 1 ⁇ m, for example, the doping thickness is 0.1 ⁇ m-1 ⁇ m, 0.1 ⁇ m-0.6 ⁇ m.
  • the coating layer has a thickness of 0.01-4 ⁇ m, such as 0.01 ⁇ m, 0.1 ⁇ m, 0.2 ⁇ m, 0.3 ⁇ m, 0.4 ⁇ m, 0.5 ⁇ m, 0.6 ⁇ m, 0.7 ⁇ m, 0.8 ⁇ m, 0.9 ⁇ m, 1 ⁇ m, 2 ⁇ m , 3 ⁇ m, 4 ⁇ m. It is preferable that the thickness of the coating layer is within a given range to avoid the problem that the coating layer thickness is too large, which affects the ionic conductivity and coating uniformity of the core material, thereby leading to a reduction in the capacity of the cathode active material. It also avoids the problem of coating layer thickness. The problem of too small improvement effect is not obvious, thus further improving the first discharge efficiency, cycle performance and rate performance of the cathode active material.
  • the thickness of the coating layer is 0.01-1 ⁇ m; further optionally, the thickness is 0.02-0.5 ⁇ m.
  • the thickness of the coating layer can be 0.01-1 ⁇ m; further, it can be 0.02-0.5 ⁇ m.
  • the peak intensity ratio of IO 2 2- /IO 2- in the coating layer is 0.5-1; optionally 0.7-0.9; wherein IO 2 2- is 531 eV in the X-ray photoelectron spectroscopy test
  • the peak intensity value of oxygen vacancies, IO 2- is the peak intensity value corresponding to lattice oxygen at 529 eV in the X-ray photoelectron spectroscopy test. Controlling the peak intensity ratio of IO 2 2- /IO 2- in the coating layer within a given range allows the coating layer to have an appropriate amount of oxygen vacancies, which can effectively inhibit the oxygen release of the material and improve the lithium-rich manganese-based cathode in the cathode active material.
  • the structural stability of the material inhibits the phase change of lithium-rich manganese-based cathode materials.
  • the molecular formula of the lithium-rich manganese-based cathode material is xLi 2 MnO 3 ⁇ (1-x)LiNi y Co z Mn a M 1-yza O 2 ,
  • M is Mg, B, Al, V, Ti, Zr, Sn At least one of Mo.
  • the above-mentioned coating layer can be applied to the above-mentioned lithium-rich manganese-based cathode material to improve its first discharge efficiency, cycle performance and rate performance.
  • lithium-rich manganese-based cathode materials include but are not limited to the following types: 0.35Li 2 MnO 3 ⁇ 0.65LiNi 0.46 Co 0.08 Mn 0.46 O 2 , 0.35Li 2 MnO 3 ⁇ 0.65LiNi 0.45 Co 0.08 Mn 0.46 Mg 0.01 O 2 , 0.35Li 2 MnO 3 ⁇ 0.65LiNi 0.45 Co 0.08 Mn 0.46 Al 0.01 O 2 , 0.35Li 2 MnO 3 ⁇ 0.65LiNi 0.45 Co 0.08 Mn 0.46 Ti 0.01 O 2 , 0.35Li 2 MnO 3 ⁇ 0.65LiNi 0 .45 Co 0.08 Mn 0.46 V 0.01 O 2 .
  • the core material is the above-mentioned lithium-rich manganese-based cathode material.
  • the core material in addition to the above-mentioned lithium-rich manganese-based cathode material, may also contain other cathode materials commonly used in the field.
  • the particle type of the lithium-rich manganese-based cathode material is secondary particles, single crystals or quasi-single crystals.
  • secondary particles refer to secondary spherical particles formed by agglomeration of primary particles.
  • the specific surface area of the lithium-rich manganese-based cathode material is ⁇ 2.0 m 2 /g, optionally 0.1-1 m 2 /g.
  • the Dv50 particle size of the lithium-rich manganese-based cathode material is 1-20 ⁇ m; optionally 3-15 ⁇ m.
  • the lithium-rich manganese-based cathode material used in the core material of the present application has a regular shape, uniform particle size distribution, and a low specific surface, so it can have a high compaction density, thereby ensuring that the secondary battery produced has a high energy density and excellent cycle performance.
  • the above-mentioned positive electrode active material usually also optionally includes a binder, a conductive agent and other optional auxiliaries.
  • the conductive agent can be one or more of superconducting carbon, acetylene black, carbon black, Ketjen black, carbon dots, carbon nanotubes, Super P(SP), graphene and carbon nanofibers.
  • the binder can be styrene-butadiene rubber (SBR), water-based acrylic resin, polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE), ethylene-vinyl acetate copolymer One or more of (EVA), polyacrylic acid (PAA), carboxymethylcellulose (CMC), polyvinyl alcohol (PVA) and polyvinyl butyral (PVB).
  • SBR styrene-butadiene rubber
  • PVDF polyvinylidene fluoride
  • PTFE polytetrafluoroethylene
  • EVA ethylene-vinyl acetate copolymer
  • PAA polyacrylic acid
  • CMC carboxymethylcellulose
  • PVA polyvinyl alcohol
  • PVB polyvinyl butyral
  • This application also provides a method for preparing the above-mentioned positive electrode active material, which includes the following steps: forming the above-mentioned coating layer on the surface of the above-mentioned core material.
  • the coating layer can be formed by using techniques commonly used in the art, such as solid phase coating method, spray method, in-situ deposition method, etc.
  • the oxygen ion conductor includes La 2 Mo 2 O 9
  • the lithium ion conductor includes LiLaO 2 and Li 2 MoO 4 ; preferably, the preparation method includes the following steps S11-S12.
  • Step S11 Mix molybdenum salt, lanthanum salt and lithium-rich manganese-based precursor in a solvent, and perform a hydrothermal reaction at 100-200°C for 8-12 hours to obtain a rich lithium-rich manganese-based precursor with La 2 Mo 2 O 9 deposited in situ on the surface. Lithium manganese based precursor.
  • Step S12 Mix the lithium-rich manganese-based precursor with La 2 Mo 2 O 9 deposited in situ on the surface and the lithium salt, and then perform a calcination treatment to obtain a positive electrode active material composite-coated with an oxygen ion conductor and a lithium ion conductor.
  • step S12 part of La 2 Mo 2 O 9 reacts with part of the lithium salt to form LiLaO 2 and Li 2 MoO 4 as lithium ion conductors, and part of La 2 Mo 2 O 9 remains as oxygen Ionic conductor; on the other hand, the lithium-rich manganese-based precursor can be reacted with the lithium salt to transform into a lithium-rich manganese-based cathode material, and some of the lanthanum and molybdenum metal ions in La 2 Mo 2 O 9 can be doped into the lithium-rich manganese base.
  • the surface layer of the positive electrode material is not limited to form LiLaO 2 and Li 2 MoO 4 as lithium ion conductors, and part of La 2 Mo 2 O 9 remains as oxygen Ionic conductor; on the other hand, the lithium-rich manganese-based precursor can be reacted with the lithium salt to transform into a lithium-rich manganese-based cathode material, and some of the lanthanum and molybdenum metal ions in La 2 Mo 2
  • the above-mentioned preparation method of the present application can synthesize a lithium-rich manganese-based material composite-coated with an oxygen ion conductor and a lithium ion conductor, in which the oxygen ion conductor includes La 2 Mo 2 O 9 and the lithium ion conductor includes LiLaO 2 and Li 2 MoO 4 , so that the cathode active material has excellent first discharge efficiency, cycle performance and rate performance.
  • the lithium-rich manganese-based precursor is Ni b Co c Mn d M (1-bcd) (OH) 2 .
  • M is at least one of Mg, B, Al, V, Ti, Zr, Sn and Mo.
  • the lithium-rich manganese-based precursor has a higher Mn content and a lower Co content, which is beneficial to reducing costs.
  • the lithium-rich manganese-based precursor can be doped during the above preparation process, which is beneficial to doping during the sintering process.
  • Metal ions are doped into the crystal lattice to improve the structural stability of the cathode active material.
  • lithium-rich manganese-based precursors include but are not limited to the following types: Ni 0.30 Co 0.05 Mn 0.65 (OH) 2 , Ni 0.29 Co 0.05 Mn 0.65 Mg 0.01 (OH) 2 , Ni 0.29 Co 0.05 Mn 0.65 Al 0.01 ( OH) 2 , Ni 0.29 Co 0.05 Mn 0.65 Ti 0.01 (OH) 2 , Ni 0.29 Co 0.05 Mn 0.65 V 0.01 (OH) 2 .
  • the solvent is at least one of water, ethanol, methanol, and ethylene glycol.
  • the molybdenum salt is at least one of ammonium molybdate, sodium molybdate, and potassium molybdate.
  • the lanthanum salt is at least one of lanthanum chloride and lanthanum nitrate.
  • the lithium salt is at least one of lithium carbonate, lithium hydroxide, and lithium acetate.
  • step S12 the molar ratio of all metal elements in the lithium element in the lithium salt and the lithium-rich manganese-based precursor with La 2 Mo 2 O 9 deposited in situ on the surface is 1: (1.1-1.8), optionally 1 :(1.1-1.5).
  • all metal elements include Ni, Co, Mn, M, Mo and La.
  • pH value of the hydrothermal reaction is 8-10.
  • the atmosphere of the calcination treatment is air.
  • the step of calcination treatment includes: pre-calcining at 300-500°C for 2-5h, and then sintering at 700-900°C for 10-20h.
  • the above preparation method has a simple process, and the prepared cathode active material has good first discharge efficiency, cycle performance and rate performance.
  • the negative electrode sheet usually includes a negative electrode current collector and a negative electrode active material layer disposed on the negative electrode current collector, and the negative electrode active material layer includes a negative electrode active material.
  • the negative electrode current collector can be a conventional metal foil or a composite current collector.
  • a metal material can be disposed on a polymer substrate to form a composite current collector.
  • the negative electrode current collector may be copper foil.
  • Commonly used negative active materials include, but are not limited to, one or more of artificial graphite, natural graphite, hard carbon materials, soft carbon, silicon-based materials and tin-based materials.
  • the silicon-based material may be selected from one or more of elemental silicon and silicon-oxygen compounds, such as silicon oxide, silicon-carbon composites, silicon-nitrogen composites, and silicon alloys.
  • the tin-based material may be selected from one or more of elemental tin, tin oxide compounds, and tin alloys. These materials are commercially available.
  • the negative active material includes silicon-based material.
  • the secondary battery further includes a separator film.
  • a separator film There is no particular restriction on the type of isolation membrane in this application. Any well-known porous structure isolation membrane with good chemical stability and mechanical stability can be used.
  • the material of the isolation membrane can be selected from at least one of glass fiber, non-woven fabric, polyethylene, polypropylene and polyvinylidene fluoride.
  • the isolation film can be a single-layer film or a multi-layer composite film, with no special restrictions. When the isolation film is a multi-layer composite film, the materials of each layer can be the same or different, without special restrictions.
  • the secondary battery may include an electrolyte that serves to conduct ions between a positive electrode and a negative electrode.
  • the electrolyte solution may include electrolyte salts and solvents.
  • the electrolyte salt may be selected from lithium hexafluorophosphate (LiPF 6 ), lithium tetrafluoroborate (LiBF 4 ), lithium perchlorate (LiClO 4 ), lithium hexafluoroarsenate (LiAsF 6 ), lithium bisfluorosulfonyl imide ( LiFSI), lithium bistrifluoromethanesulfonimide (LiTFSI), lithium trifluoromethanesulfonate (LiTFS), lithium difluoromethanesulfonate borate (LiDFOB), lithium dioxalatoborate (LiBOB), lithium difluorophosphate (LiPO 2 F 2 ), one or more of lithium difluorodioxalate phosphate (LiDFOP) and lithium tetrafluorooxalate phosphate (LiTFOP).
  • LiFSI lithium bisfluorosulfonyl imide
  • LiTFSI lithium bis
  • the solvent may be selected from ethylene carbonate (EC), propylene carbonate (PC), ethyl methyl carbonate (EMC), diethyl carbonate (DEC), dimethyl carbonate (DMC), carbonic acid Dipropyl carbonate (DPC), methylpropyl carbonate (MPC), ethylpropyl carbonate (EPC), butylene carbonate (BC), fluoroethylene carbonate (FEC), methyl formate (MF), methyl acetate (MA), ethyl acetate (EA), propyl acetate (PA), methyl propionate (MP), ethyl propionate (EP), propyl propionate (PP), methyl butyrate (MB), One or more of ethyl butyrate (EB), 1,4-butyrolactone (GBL), sulfolane (SF), dimethyl sulfone (MSM), methyl ethyl sulfone (EMS) and diethyl sulf
  • additives are also included in the electrolyte.
  • additives may include negative electrode film-forming additives, positive electrode film-forming additives, and may also include additives that can improve certain properties of the battery, such as additives that improve the overcharge performance of the battery, additives that improve the high-temperature performance of the battery, and additives that improve the low-temperature performance of the battery. Additives etc.
  • the secondary battery of the present application is a lithium-ion secondary battery.
  • the secondary battery can be prepared according to conventional methods in the art, for example, the positive electrode sheet, the separator film, and the negative electrode sheet are wound (or stacked) in order, so that the separator film is between the positive electrode sheet and the negative electrode sheet for isolation. function to obtain the battery core, place the battery core in the outer package, inject the electrolyte and seal it to obtain a secondary battery.
  • the embodiments of the present application have no particular limitation on the shape of the secondary battery, which may be cylindrical, square, or any other shape. As shown in FIG. 1 , a square-structured secondary battery 5 is shown as an example.
  • the secondary battery may include an outer packaging.
  • the outer packaging is used to encapsulate the positive electrode piece, the negative electrode piece and the electrolyte.
  • the outer package may include a housing 51 and a cover 53 .
  • the housing 51 may include a bottom plate and side plates connected to the bottom plate, and the bottom plate and the side plates enclose a receiving cavity.
  • the housing 51 has an opening communicating with the accommodation cavity, and the cover plate 53 can cover the opening to close the accommodation cavity.
  • the positive electrode piece, the negative electrode piece and the isolation film can be formed into the electrode assembly 52 through a winding process or a lamination process.
  • the electrode assembly 52 is packaged in the containing cavity.
  • the electrolyte soaks into the electrode assembly 52 .
  • the number of electrode assemblies 52 contained in the secondary battery 5 can be one or more, and can be adjusted according to needs.
  • the outer packaging of the secondary battery may be a hard shell, such as a hard plastic shell, an aluminum shell, a steel shell, etc.
  • the outer packaging of the secondary battery may also be a soft bag, such as a bag-type soft bag.
  • the soft bag may be made of plastic, such as one or more of polypropylene (PP), polybutylene terephthalate (PBT), polybutylene succinate (PBS), and the like.
  • secondary batteries can be assembled into battery modules, and the number of secondary batteries contained in the battery module can be multiple. The specific number can be adjusted according to the application and capacity of the battery module.
  • FIG 3 is a battery module 4 as an example.
  • a plurality of secondary batteries 5 may be arranged in sequence along the length direction of the battery module 4 .
  • the plurality of secondary batteries 5 can be fixed by fasteners.
  • the battery module 4 may further include a housing having a receiving space in which a plurality of secondary batteries 5 are received.
  • the above-mentioned battery modules can also be assembled into a battery pack, and the number of battery modules contained in the battery pack can be adjusted according to the application and capacity of the battery pack.
  • FIGS. 4 and 5 show the battery pack 1 as an example.
  • the battery pack 1 may include a battery box and a plurality of battery modules 4 arranged in the battery box.
  • the battery box includes an upper box 2 and a lower box 3.
  • the upper box 2 can be covered with the lower box 3 and form a closed space for accommodating the battery module 4.
  • Multiple battery modules 4 can be arranged in the battery box in any manner.
  • the present application also provides an electrical device, which includes at least one of the secondary battery, battery module, or battery pack.
  • the secondary battery, battery module or battery pack may be used as a power source for the device or as an energy storage unit for the device.
  • the device may be, but is not limited to, a mobile device such as a mobile phone or a laptop computer, or an electric vehicle such as a pure electric vehicle, a hybrid electric vehicle, a plug-in hybrid electric vehicle, an electric bicycle, an electric scooter, an electric golf cart, an electric truck, etc. Vehicles, or electric trains, ships and satellites, energy storage systems, etc.
  • the device can select secondary batteries, battery modules or battery packs according to its usage requirements.
  • FIG. 6 is an example device.
  • the electric device 6 is a pure electric vehicle, a hybrid electric vehicle, a plug-in hybrid electric vehicle, or the like.
  • battery packs or battery modules can be used.
  • the device may be a mobile phone, a tablet, a laptop, etc.
  • the device is usually required to be thin and light, and a secondary battery can be used as a power source.
  • step S2 Add the molybdenum salt (ammonium molybdate) and lanthanum salt (lanthanum nitrate) solutions in step S1 dropwise into the precursor dispersion under water bath conditions and adjust the pH of the solution to 9, and then stir the solution at room temperature for 4 hours. Then transfer to the reaction kettle and perform a hydrothermal reaction at 100-200°C for 8-12 hours. After the reaction kettle is cooled to room temperature, the molybdenum salt and the lanthanum salt are generated and lanthanum molybdate (La 2 Mo 2 O 9 ) is deposited in situ to Precursor surface;
  • step S3 Wash the precursor product obtained in step S2 with deionized water and vacuum-dry, then mix it with lithium salt (lithium carbonate) by ball milling, first pre-calcining at 300-500°C for 2 hours, and then high temperature at 700-900°C. Sintering for 10-20 hours, and then naturally cooled to room temperature, the surface-coated lithium-rich manganese-based cathode material is obtained.
  • the surface of the lithium-rich manganese-based cathode material is coated with a composite coating layer of the oxygen ion conductor La 2 Mo 2 O 9 and the lithium ion conductors LiLaO 2 and Li 2 MoO 4 .
  • Table 1 The specific parameters are shown in Table 1.
  • Li/Me in Table 1 refers to the molar ratio of the lithium element in the lithium salt (lithium carbonate) added in step S3 to all metal elements in the precursor product added in step S3. It can be understood that the amounts of all metal elements in the precursor product added in step S3 can be obtained through element testing.
  • Dv50 refers to the particle size corresponding to 50% of the volume distribution.
  • Dv50 can be easily measured using a laser particle size analyzer, such as the Mastersizer 2000E laser particle size analyzer of Malvern Instruments Co., Ltd. in the United Kingdom, referring to the GB/T 19077-2016 particle size distribution laser diffraction method.
  • the thickness of molybdenum and lanthanum doped into the core material can be characterized by the well-known ion polished profile (CP) element surface scanning and line scan analysis.
  • CP ion polished profile
  • the molar ratio of La:Mo and the contents of La and Mo of the coating layer can be measured using the well-known X-ray energy spectrometer (EDS) for area scan analysis and the inductively coupled plasma optical emission spectrometer (ICP-AES) for test and analysis respectively.
  • EDS X-ray energy spectrometer
  • ICP-AES inductively coupled plasma optical emission spectrometer
  • IO 2 2- /IO 2- can be analyzed using the well-known X-ray photoelectron spectroscopy (XPS), where IO 2 2- is the peak intensity value of the oxygen vacancy at 531eV in the X-ray photoelectron spectroscopy test, and IO 2- is the corresponding The peak intensity of lattice oxygen at 529eV in the X-ray photoelectron spectroscopy test.
  • XPS X-ray photoelectron spectroscopy
  • the thickness of the cladding layer is the total thickness of all cladding layers.
  • core materials 1-5 are respectively 0.35Li 2 MnO 3 ⁇ 0.65LiNi 0.46 Co 0.08 Mn 0.46 O 2 , 0.35Li 2 MnO 3 ⁇ 0.65LiNi 0.45 Co 0.08 Mn 0.46 Mg 0.01 O 2 , 0.35Li 2 MnO 3 ⁇ 0.65 LiNi 0.45 Co 0.08 Mn 0.46 Al 0.01 O 2 , 0.35Li 2 MnO 3 ⁇ 0.65LiNi 0.45 Co 0.08 Mn 0.46 Ti 0.01 O 2 , 0.35Li 2 MnO 3 ⁇ 0.65LiNi 0.45 Co 0.08 Mn 0.46 V 0. 01 O 2 .
  • the lithium-rich manganese-based cathode material 0.35Li 2 MnO 3 ⁇ 0.65LiNi 0.45 Co 0.08 Mn 0.46 Al 0.01 O 2 and the oxygen ion conductor La 2 Mo 2 O 9 and the lithium ion conductor LiLaO 2 are solid-phase mixed. After the mixing is completed, Pre-calcining at 400°C for 2 hours in an air atmosphere, and then holding at 800°C for 12 hours, yields the modified lithium-rich manganese-based cathode material;
  • Example 7-13 the same preparation method as in Example 6 was used except that the composition of each raw material was changed as shown in Table 2.
  • the above-mentioned positive electrode active materials 1-13, conductive carbon black (SP), and polyvinylidene fluoride (PVDF) are mixed according to the mass ratio of 96.8:2.2:1, dissolved in N-methylpyrrolidone (NMP), and slurried to prepare The positive electrode slurry is coated on aluminum foil with a width of 400mm, dried, cold pressed, and cut to obtain positive electrode sheets.
  • Positive electrode piece Use the positive electrode piece 1-13 prepared above.
  • Isolation membrane Use polyethylene (PE) porous polymeric membrane as the isolation membrane
  • Negative electrode plate combine graphite, binder styrene-butadiene rubber (SBR), binder polyacrylic acid (PAA), dispersant (CMC-Na), conductive carbon black (Super-P, SP), carbon nanotubes (CNT) is fully stirred and mixed in an appropriate amount of deionized water at a weight ratio of 95%: 2%: 1%: 1%: 0.7%: 0.3% to prepare a negative electrode slurry. The negative electrode slurry is then coated on a 6 ⁇ m thick copper foil, dried and cold pressed to form a negative electrode active material layer, and then cut into negative electrode pieces.
  • SBR binder styrene-butadiene rubber
  • PAA binder polyacrylic acid
  • CMC-Na dispersant
  • Super-P, SP conductive carbon black
  • CNT carbon nanotubes
  • Electrolyte After mixing ethylene carbonate (EC), ethyl methyl carbonate (EMC), and diethyl carbonate (DEC) according to the volume ratio of 3:6:1, add the fully dried lithium salt (LiPF6) according to the volume ratio. Dissolved in mixed organic solvents at a ratio of 1mol/L. Obtain the required electrolyte.
  • EC ethylene carbonate
  • EMC ethyl methyl carbonate
  • DEC diethyl carbonate
  • Full battery assembly Stack the above-mentioned positive electrode plates, isolation films, and negative electrode plates in order, so that the isolation film is between the positive and negative electrodes for isolation, and wind them to obtain a bare battery core. Place the bare battery core in the outer aluminum shell, inject the electrolyte prepared above into the high-temperature dried dry battery, and go through processes such as vacuum packaging, standing, formation, and shaping to obtain a lithium-ion secondary battery 1- 13, as shown in Table 3.
  • the performance evaluation of each battery 1-13 is carried out according to the following method.
  • batteries 1-13 were charged to 3.4V at a constant current of 0.02C at 45°C, left to stand for 5 minutes, and then charged to 3.75V at a constant current of 0.1C.
  • the recorded capacity was Z1, and then vented and Second seal, place the second sealed battery at 25°C, charge with constant current at 0.33C to 4.5V, charge with constant voltage to 0.02C, let stand for 5 minutes, record capacity is Z2; then discharge at 0.33C to 2.0V.
  • the recording capacity is D1.
  • first time efficiency D1/(Z1+Z2).
  • the coating layer of the cathode active material in Comparative Example 1 does not contain an oxygen ion conductor, and the coating layer of Comparative Example 2 does not contain a lithium ion conductor.
  • the coating layer of the cathode active material in each embodiment It also contains an oxygen ion conductor and a lithium ion conductor; compared with the comparative example, the secondary batteries prepared in each embodiment have better first discharge efficiency, cycle performance and rate performance.
  • Examples 1-5 and 6-11 it can be seen that in Examples 1-5, a specific type of oxygen ion conductor and a lithium ion conductor are used in conjunction, and the secondary battery produced can have better first-time performance at the same time. Discharge efficiency, cycle performance and rate performance.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Electrochemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Inorganic Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Composite Materials (AREA)
  • Manufacturing & Machinery (AREA)
  • Materials Engineering (AREA)
  • Organic Chemistry (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Battery Electrode And Active Subsutance (AREA)
  • Inorganic Compounds Of Heavy Metals (AREA)
  • Secondary Cells (AREA)

Abstract

本申请涉及一种正极活性材料及其制备方法、极片、二次电池及用电装置。其中，该正极活性材料，包括：内核材料，包含有富锂锰基正极材料；包覆层，包覆在所述内核材料的外表面，所述包覆层包含有氧离子导体和锂离子导体。

Description

正极活性材料及其制备方法、极片、二次电池及用电装置 技术领域
本申请属于二次电池技术领域，具体涉及一种正极活性材料及其制备方法、极片、二次电池及用电装置。
背景技术
二次电池因具有重量轻、无污染、无记忆效应等突出特点，被广泛应用于各类消费类电子产品和电动车辆中。
随着对动力电池能量密度的要求的提升，众多的正极材料被开发出来。例如高镍三元正极材料，其虽然具有较高的能量密度，但是对制备技术及存储环境要求都极为苛刻。相比之下，富锂锰基正极材料是一种被寄予厚望的正极材料，其具有较高的放电比容，差不多是磷酸铁锂的两倍，且其由于含有锰，制备成本相对较低。然而富锂锰基正极材料的首次放电效率、循环性能和倍率性能较差，大大阻碍了其实际应用。
发明内容
鉴于背景技术中存在的技术问题，本申请提供一种正极活性材料，其应用于二次电池，能够提高二次电池的首次放电效率、循环性能和倍率性能。
为了实现上述目的，本申请的第一方面提供一种正极活性材料，包括：
内核材料，包含有富锂锰基正极材料；
包覆层，包覆在所述内核材料的外表面，所述包覆层包含有氧离子导体和锂离子导体。
相对于现有技术，本申请至少包括如下所述的有益效果：
本申请的正极活性材料，通过在含有富锂锰基正极材料的内核材料的 外表面、形成上述同时包含有氧离子导体和锂离子导体的包覆层。氧离子导体和锂离子导体协同引入作为含有富锂锰基正极材料的内核材料的包覆层，氧离子导体的内部有着较高的氧空位浓度，具有高氧吸附和存储能力，进而可有效抑制富锂锰基晶格氧的释放，同时还能减少锂离子的脱出，进而提升正极活性材料的首次充放电效率。同时，富锂锰基正极材料晶格释氧得到抑制，富锂锰基正极材料的结构稳定性得到提升，进而可以提升正极活性材料的循环稳定性。与此同时，引入锂离子导体，其具有较高的离子电导率，提升锂离子的传输速率，减少锂离子的脱出，进而可提升正极活性材料的容量和倍率性能。
在本申请任意实施方式中，所述氧离子导体包括La 2Mo 2O 9及萤石型氧离子导体中的至少一种。
在本申请任意实施方式中，所述萤石型氧离子导体包括ZrO 2、CeO 2及GeO 2中的至少一种。
在本申请任意实施方式中，所述锂离子导体包括LiLaO 2、Li 2MoO 4、Li 3PO 4，Li 3BO 3及LiTaO 3中的至少一种。
在本申请任意实施方式中，所述氧离子导体包含La 2Mo 2O 9；所述锂离子导体包含LiLaO 2和Li 2MoO 4。
在本申请任意实施方式中，所述包覆层中镧原子和钼原子的摩尔比为1：(1.02-1.1)；可选为1：(1.02-1.05)。
在本申请任意实施方式中，所述包覆层中钼原子的含量为300-5000ppm；和/或，
所述包覆层中镧原子的含量为500-5000ppm。
在本申请任意实施方式中，所述包覆层中钼原子的含量为1000-4000ppm；和/或，
所述包覆层中镧原子的含量为1000-3000ppm。
在本申请任意实施方式中，所述内核材料的表面掺杂有镧原子和钼原 子。
在本申请任意实施方式中，所述内核材料掺杂有镧原子和钼原子的表面厚度不大于3μm；可选为不大于2μm。
在本申请任意实施方式中，所述包覆层的厚度为0.01-4μm。
在本申请任意实施方式中，所述包覆层的厚度为0.02-1μm。
在本申请任意实施方式中，所述包覆层中IO 2 2-/IO 2-的峰强比为0.5-1；可选为0.7-0.9；
其中，IO 2 2-为X射线光电子能谱测试中531eV的氧空位的峰强值，IO 2-为对应于X射线光电子能谱测试中529eV的晶格氧的峰强值。
在本申请任意实施方式中，所述富锂锰基正极材料的分子式为xLi 2MnO 3·(1-x)LiNi yCo zMn aM 1-y-z-aO 2，
其中0<x<1，0≤y≤1，0≤z≤1，0≤a≤1，0<y+z+a≤1；M为Mg、B、Al、V、Ti、Zr、Sn和Mo中至少一种。
在本申请任意实施方式中，所述富锂锰基正极材料的颗粒类型为二次颗粒、单晶或类单晶；和/或，
所述富锂锰基正极材料的比表面积＜2.0m 2/g，可选0.1-1m 2/g；
所述富锂锰基正极材料的Dv50粒径为1-20μm；可选3-15μm。
本申请的第二方面提供一种本发明第一方面的正极活性材料的制备方法，包括如下步骤：
在所述内核材料的表面形成所述包覆层。
在本申请任意实施方式中，所述氧离子导体包含La 2Mo 2O 9，所述锂离子导体包含LiLaO 2和Li 2MoO 4；所述制备方法包括如下步骤：
将钼盐、镧盐及富锂锰基前驱体在溶剂中混合，并于100-200℃下进行水热反应8-12h，得到表面原位沉积有La 2Mo 2O 9的富锂锰基前驱体；
将所述表面原位沉积有La 2Mo 2O 9的富锂锰基前驱体与锂盐混合后，进行煅烧处理，得到氧离子导体和锂离子导体复合包覆的正极活性材料。
在本申请任意实施方式中，所述富锂锰基前驱体为Ni bCo cMn dM (1-b-c- d)(OH) 2，
其中0＜b＜0.4，0≤c≤0.05，0.6≤d＜1，M为Mg、B、Al、V、Ti、Zr、Sn和Mo中至少一种。
在本申请任意实施方式中，所述溶剂为水、乙醇、甲醇及乙二醇中的至少一种；和/或，
所述钼盐为钼酸铵、钼酸钠及钼酸钾中的至少一种；和/或，
所述镧盐为氯化镧及硝酸镧中的至少一种；和/或，
所述锂盐为碳酸锂、氢氧化锂及醋酸锂中的至少一种；和/或，
所述锂盐中锂元素和所述表面原位沉积有La 2Mo 2O 9的富锂锰基前驱体中的所有金属元素的摩尔比为1：(1.1-1.8)，可选为1：(1.1-1.5)；和/或，
所述水热反应的pH值为8-10；和/或，
所述煅烧处理的气氛为空气；和/或，
所述煅烧处理的步骤包括：先于300-500℃下进行预煅烧2-5h，然后于700-900℃下烧结10-20h。
本申请的第三方面提供一种正极极片，包括：
正极集流体；及
正极活性材料层，所述正极活性材料层位于所述正极集流体的表面，所述正极活性材料层的组分包括本申请的第一方面提供的正极活性材料或本申请的第二方面提供的制备方法制得的正极活性材料。
本申请的第四方面提供一种二次电池，包括本申请的第三方面提供的正极极片。
本申请的第五方面提供一种用电装置，包括本申请的第四方面提供的二次电池。
附图说明
为了更清楚地说明本申请的技术方案，下面将对本申请中所使用的附图作简单介绍。显而易见地，下面所描述的附图仅仅是本申请的一些实施方式，对于本领域普通技术人员来讲，在不付出创造性劳动的前提下，还可以根据附图获得其他的附图。
图1是二次电池的一实施方式的示意图。
图2是图1的分解图。
图3是电池模块的一实施方式的示意图。
图4是电池包的一实施方式的示意图。
图5是图4的分解图。
图6是二次电池用作电源的用电装置的一实施方式的示意图。
附图标记说明：
1、电池包；2、上箱体；3、下箱体；4、电池模块；5、二次电池；51、壳体；52、电极组件；53、盖板；6、用电装置。
具体实施方式
下面结合具体实施方式，进一步阐述本申请。应理解，这些具体实施方式仅用于说明本申请而不用于限制本申请的范围。
为了简明，本文仅具体地公开了一些数值范围。然而，任意下限可以与任意上限组合形成未明确记载的范围；以及任意下限可以与其它下限组合形成未明确记载的范围，同样任意上限可以与任意其它上限组合形成未明确记载的范围。此外，每个单独公开的点或单个数值自身可以作为下限或上限与任意其它点或单个数值组合或与其它下限或上限组合形成未明确记载的范围。
在本文的描述中，需要说明的是，除非另有说明，“以上”、“以下”为包括本数，“一种或多种”中“几种”的含义是两种及两种以上。
在本文的描述中，除非另有说明，术语“或(or)”是包括性的。也就是 说，短语“A或(or)B”表示“A，B，或A和B两者”。更具体地，以下任一条件均满足条件“A或B”：A为真(或存在)并且B为假(或不存在)；A为假(或不存在)而B为真(或存在)；或A和B都为真(或存在)。除非另有说明，本申请中使用的术语具有本领域技术人员通常所理解的公知含义。除非另有说明，本申请中提到的各参数的数值可以用本领域常用的各种测量方法进行测量(例如，可以按照在本申请的实施例中给出的方法进行测试)。
二次电池
二次电池，是指在电池放电后可通过充电的方式使活性材料激活而继续使用的电池。
通常情况下，二次电池包括正极极片、负极极片、隔离膜及电解质。在电池充放电过程中，活性离子在正极极片和负极极片之间往返嵌入和脱出。隔离膜设置在正极极片和负极极片之间，起到隔离的作用。电解质在正极极片和负极极片之间起到传导离子的作用。
正极极片
在二次电池中，所述正极极片通常包括正极集流体及设置在正极集流体上的正极活性材料层，正极活性材料层包括正极活性材料。
所述正极集流体可以采用常规金属箔片或复合集流体。其中，可以将金属材料设置在高分子基材上形成复合集流体。作为示例，正极集流体可以采用铝箔。
如背景技术所述，富锂锰基正极材料虽然具有较高的放电比容，然而其首次放电效率、循环性能和倍率性能较差，大大阻碍了其实际应用。
本申请的技术人员经大量研究发现，富锂锰基正极材料在首圈4.5V以上的高电压充电状态下，富锂锰基正极材料容易发生释氧问题，同时过渡金属层中的部分锂离子会和O 2-一起脱除，形成Li 2O脱出，这部分晶体空位在后续的充放电过程中较难再接纳锂离子，导致富锂锰基正极材料的首次充 放电效率降低。同时富锂锰基正极材料内部大量氧空位的形成，容易导致富锂锰基正极材料中的过渡金属离子发生迁移，致使晶体结构发生重排引起富锂锰基正极材料结构的不稳定的问题，进而造成循环性能变差。此外由于富锂锰基正极本身电子和离子电导率较低，且高电压下富锂锰基正极表面与电解液的副反应加剧，导致富锂锰基正极的倍率性能极差。
基于此，本申请一实施方式提供了一种正极活性材料，其包括内核材料及包覆层。其中，内核材料包含有富锂锰基正极材料。包覆层包覆在内核材料的外表面，包覆层包含有氧离子导体和锂离子导体。
不希望限于任何理论，本申请的正极活性材料，通过在含有富锂锰基正极材料的内核材料的外表面、形成上述同时包含有氧离子导体和锂离子导体的包覆层。氧离子导体和锂离子导体协同引入作为含有富锂锰基正极材料的内核材料的包覆层，氧离子导体的内部有着较高的氧空位浓度，具有高氧吸附和存储能力，进而可有效抑制富锂锰基晶格氧的释放，同时还能减少锂离子的脱出，进而提升正极活性材料的首次充放电效率。同时，富锂锰基正极材料晶格释氧得到抑制，富锂锰基正极材料的结构稳定性得到提升，进而可以提升正极活性材料的循环稳定性。与此同时，引入锂离子导体，其具有较高的离子电导率，提升锂离子的传输速率，减少锂离子的脱出，进而可提升正极活性材料的容量和倍率性能。
上述正极极片，其正极活性材料层中的组分包括上述包覆型的正极活性材料。
本申请的技术人员经深入研究发现，当本申请的正极活性材料在满足上述设计条件的基础上，若还可选地满足下述条件中的一个或几个时，可以进一步改善二次电池的性能。
在一些实施方式中，氧离子导体包括但不限于：La 2Mo 2O 9及萤石型氧离子导体中的至少一种。进一步地，萤石型氧离子导体包括ZrO 2、CeO 2及GeO 2中的至少一种。
在一些实施方式中，锂离子导体包括但不限于：LiLaO 2、Li 2MoO 4、Li 3PO 4，Li 3BO 3及LiTaO 3中的至少一种。
在一些实施方式中，锂离子导体包含LiLaO 2和Li 2MoO 4，采用特定的两种锂离子导体的结合，能显著提升正极材料的离子电导率，同时还能有效抑制富锂锰基材料的阳离子混排和Mn 3+的溶出。在一些实施方式中，氧离子导体包含La 2Mo 2O 9，锂离子导体包含LiLaO 2和Li 2MoO 4。由于氧离子导体和锂离子导体具有相同的元素，采用该特定组合，二者之间会具有良好的相容性，使得包覆层中的氧离子和锂离子导体二者结合得更紧密，有利于提高包覆层本身的稳定性和离子的快速传导。
进一步地，包覆层中镧原子和钼原子的摩尔比为1：(1.02-1.1)；进一步优选为1：(1.02-1.05)。通过控制包覆层中钼和镧的摩尔比能够确保合成出化学计量数比的钼酸镧。
进一步地，包覆层中钼原子的含量为300-5000ppm，可选为1000-4000ppm。进一步地，包覆层中镧原子的含量为500-5000ppm；可选为1000-3000ppm。控制包覆层中钼原子和镧原子的含量，可以确保包覆层不会过厚，影响正极活性材料的容量发挥，从而达到较佳的包覆效果。
可理解，当在内核材料表面原位形成La 2Mo 2O 9时，内核材料的表面会掺杂有镧原子和钼原子。进一步地，内核材料掺杂有镧原子和钼原子的表面厚度不大于3μm；可选为不大于2μm。进一步可选地，内核材料掺杂有镧原子和钼原子的表面厚度不大于1μm，例如掺杂厚度为0.1μm-1μm、0.1μm-0.6μm。
在一些实施方式中，包覆层的厚度为0.01-4μm，例如0.01μm、0.1μm、0.2μm、0.3μm、0.4μm、0.5μm、0.6μm、0.7μm、0.8μm、0.9μm、1μm、2μm、3μm、4μm。优选包覆层的厚度在给定范围，避免包覆层厚度太大，影响内核材料的离子传导性和包覆均匀性，进而导致正极活性材料的容量降低的问题，还可避免包覆层厚度太小改善效果不明显的问题，如此进一步提升正 极活性材料的首次放电效率、循环性能和倍率性能。
可选地，包覆层的厚度为0.01-1μm；进一步可选为0.02-0.5μm。例如氧离子导体包含La 2Mo 2O 9，锂离子导体包含LiLaO 2和Li 2MoO 4时，包覆层的厚度可选为0.01-1μm；进一步可选为0.02-0.5μm。
在一些实施方式中，包覆层中IO 2 2-/IO 2-的峰强比为0.5-1；可选为0.7-0.9；其中，IO 2 2-为X射线光电子能谱测试中531eV的氧空位的峰强值，IO 2-为对应于X射线光电子能谱测试中529eV的晶格氧的峰强值。控制包覆层中IO 2 2-/IO 2-的峰强比在给定范围，使得包覆层中具有适量氧空位，能有效抑制材料氧释放，提升正极活性材料中的富锂锰基正极材料的结构稳定性，抑制富锂锰基正极材料的相变。
在一些实施方式中，富锂锰基正极材料的分子式为xLi 2MnO 3·(1-x)LiNi yCo zMn aM 1-y-z-aO 2，
其中0<x<1，0≤y≤1，0≤z≤1，0≤a≤1，0<y+z+a≤1；M为Mg、B、Al、V、Ti、Zr、Sn和Mo中至少一种。上述包覆层可适用于上述的富锂锰基正极材料，以改善其首次放电效率、循环性能和倍率性能。
可选地，富锂锰基正极材料包括但不限于如下种类：0.35Li 2MnO 3·0.65LiNi 0.46Co 0.08Mn 0.46O 2、0.35Li 2MnO 3·0.65LiNi 0.45Co 0.08Mn 0.46Mg 0.01O 2、0.35Li 2MnO 3·0.65LiNi 0.45Co 0.08Mn 0.46Al 0.01O 2、0.35Li 2MnO 3·0.65LiNi 0.45Co 0.08Mn 0.46Ti 0.01O 2、0.35Li 2MnO 3·0.65LiNi 0.45Co 0.08Mn 0.46V 0.01O 2。
可理解，在一些实施方式中，内核材料为上述富锂锰基正极材料。在另一些实施方式中，内核材料中除了含有上述富锂锰基正极材料，还可含有其他的本领域常用的正极材料。
在一些实施方式中，富锂锰基正极材料的颗粒类型为二次颗粒、单晶或类单晶。其中，二次颗粒是指由一次颗粒团聚而成的二次球颗粒。
在一些实施方式中，富锂锰基正极材料的比表面积＜2.0m 2/g，可选0.1-1m 2/g。
在一些实施方式中，富锂锰基正极材料的Dv50粒径为1-20μm；可选3-15μm。
本申请的内核材料所用的富锂锰基正极材料形貌规则，粒度分布均匀，具有较低的比表面，故而可具有较高的压实密度，从而确保了制得的二次电池具有较高的能量密度及优异的循环性能。
上述正极活性材料通常还可选地包括粘结剂、导电剂和其他可选助剂。
作为示例，导电剂可以为超导碳、乙炔黑、炭黑、科琴黑、碳点、碳纳米管、Super P(SP)、石墨烯及碳纳米纤维中一种或多种。
作为示例，粘结剂可以为丁苯橡胶(SBR)、水性丙烯酸树脂(water-based acrylic resin)、聚偏二氟乙烯(PVDF)、聚四氟乙烯(PTFE)、乙烯-醋酸乙烯酯共聚物(EVA)、聚丙烯酸(PAA)、羧甲基纤维素(CMC)、聚乙烯醇(PVA)及聚乙烯醇缩丁醛(PVB)中的一种或多种。
本申请还提供了上述正极活性材料的制备方法，包括如下步骤：在上述内核材料的表面形成上述包覆层。
可理解，形成包覆层的方式可采用本领域常用的技术，例如固相包覆法、喷雾法、原位沉积法等。
在一些实施方式中，氧离子导体包含La 2Mo 2O 9，锂离子导体包含LiLaO 2和Li 2MoO 4；优选地，其可制备方法包括如下步骤S11-S12。
步骤S11、将钼盐、镧盐及富锂锰基前驱体在溶剂中混合，并于100-200℃下进行水热反应8-12h，得到表面原位沉积有La 2Mo 2O 9的富锂锰基前驱体。
步骤S12、将表面原位沉积有La 2Mo 2O 9的富锂锰基前驱体与锂盐混合后，进行煅烧处理，得到氧离子导体和锂离子导体复合包覆的正极活性材料。
如此，通过步骤S12的煅烧处理步骤，一方面使部分La 2Mo 2O 9与部分 锂盐发生反应形成LiLaO 2和Li 2MoO 4作为锂离子导体，部分的La 2Mo 2O 9保留作为氧离子导体；另一方面还可使富锂锰基前驱体与锂盐反应转化为富锂锰基正极材料并使La 2Mo 2O 9中的部分镧和钼金属离子掺杂进入富锂锰基正极材料的表层。
本申请上述的制备方法，可以合成出氧离子导体和锂离子导体复合包覆的富锂锰基材料，其中氧离子导体包含La 2Mo 2O 9，锂离子导体包含LiLaO 2和Li 2MoO 4，使正极活性材料具有优良的首次放电效率、循环性能和倍率性能。
在一些实施方式中，富锂锰基前驱体为Ni bCo cMn dM (1-b-c-d)(OH) 2。
其中，0＜b＜0.4，0≤c≤0.05，0.6≤d＜1，M为Mg、B、Al、V、Ti、Zr、Sn和Mo中至少一种。富锂锰基前驱体中的Mn含量较高，Co含量较低，有利于降低成本，同时在上述制备过程中可对富锂锰基前驱体进行掺杂，有利于在烧结过程中将掺杂金属离子掺杂进入晶格中，提升正极活性材料的结构稳定性。
可选地，富锂锰基前驱体包括但不限于如下种类：Ni 0.30Co 0.05Mn 0.65(OH) 2、Ni 0.29Co 0.05Mn 0.65Mg 0.01(OH) 2、Ni 0.29Co 0.05Mn 0.65Al 0.01(OH) 2、Ni 0.29Co 0.05Mn 0.65Ti 0.01(OH) 2、Ni 0.29Co 0.05Mn 0.65V 0.01(OH) 2。
在一些实施方式中，溶剂为水、乙醇、甲醇及乙二醇中的至少一种。
在一些实施方式中，钼盐为钼酸铵、钼酸钠及钼酸钾中的至少一种。
在一些实施方式中，镧盐为氯化镧及硝酸镧中的至少一种。
在一些实施方式中，锂盐为碳酸锂、氢氧化锂及醋酸锂中的至少一种。
进一步地，步骤S12中锂盐中锂元素和表面原位沉积有La 2Mo 2O 9的富锂锰基前驱体中所有金属元素的摩尔比为1：(1.1-1.8)，可选为1：(1.1-1.5)。其中，所有金属元素包括Ni、Co、Mn、M及Mo和La。如此，可确保步骤S12中加入的锂盐既能满足富锂锰基前驱体要形成富锂锰基正极材料所需的锂，同时也能满足表面La 2Mo 2O 9部分反应形成LiLaO 2和Li 2MoO 4所 需的锂。
进一步地，水热反应的pH值为8-10。
进一步地，煅烧处理的气氛为空气。
进一步地，煅烧处理的步骤包括：先于300-500℃下进行预煅烧2-5h，然后于700-900℃下烧结10-20h。
上述制备方法，工艺简单，制得的正极活性材料具有良好的首次放电效率、循环性能和倍率性能。
负极极片
在二次电池中，所述负极极片通常包括负极集流体及设置在负极集流体上的负极活性材料层，负极活性材料层中包括负极活性材料。
所述负极集流体可以采用常规金属箔片或复合集流体，例如可以将金属材料设置在高分子基材上形成复合集流体。作为示例，负极集流体可以采用铜箔。
常用的负极活性材料包括，但不限于，人造石墨、天然石墨、硬碳材料、软碳、硅基材料和锡基材料中的一种或多种。所述硅基材料可选自单质硅、硅氧化合物，例如氧化亚硅、硅碳复合物、硅氮复合物、硅合金中的一种或多种。所述锡基材料可选自单质锡、锡氧化合物、锡合金中的一种或多种。这些材料均可以通过商业途径获得。在一些实施方式中，为了进一步提高电池的能量密度，所述负极活性材料包括硅基材料。
隔离膜
在一些实施方式中，二次电池中还包括隔离膜。本申请对隔离膜的种类没有特别的限制，可以选用任意公知的具有良好的化学稳定性和机械稳定性的多孔结构隔离膜。
在一些实施方式中，隔离膜的材质可选自玻璃纤维、无纺布、聚乙烯、聚丙烯及聚偏二氟乙烯中的至少一种。隔离膜可以是单层薄膜，也可以是多层复合薄膜，没有特别限制。在隔离膜为多层复合薄膜时，各层的材料可以 相同或不同，没有特别限制。
电解液
二次电池可以包括电解液，电解液在正极和负极之间起到传导离子的作用。所述电解液可以包括电解质盐和溶剂。
作为示例，电解质盐可选自六氟磷酸锂(LiPF 6)、四氟硼酸锂(LiBF 4)、高氯酸锂(LiClO 4)、六氟砷酸锂(LiAsF 6)、双氟磺酰亚胺锂(LiFSI)、双三氟甲磺酰亚胺锂(LiTFSI)、三氟甲磺酸锂(LiTFS)、二氟草酸硼酸锂(LiDFOB)、二草酸硼酸锂(LiBOB)、二氟磷酸锂(LiPO 2F 2)、二氟二草酸磷酸锂(LiDFOP)及四氟草酸磷酸锂(LiTFOP)中的一种或多种。
作为示例，所述溶剂可选自碳酸亚乙酯(EC)、碳酸亚丙酯(PC)、碳酸甲乙酯(EMC)、碳酸二乙酯(DEC)、碳酸二甲酯(DMC)、碳酸二丙酯(DPC)、碳酸甲丙酯(MPC)、碳酸乙丙酯(EPC)、碳酸亚丁酯(BC)、氟代碳酸亚乙酯(FEC)、甲酸甲酯(MF)、乙酸甲酯(MA)、乙酸乙酯(EA)、乙酸丙酯(PA)、丙酸甲酯(MP)、丙酸乙酯(EP)、丙酸丙酯(PP)、丁酸甲酯(MB)、丁酸乙酯(EB)、1,4-丁内酯(GBL)、环丁砜(SF)、二甲砜(MSM)、甲乙砜(EMS)及二乙砜(ESE)中的一种或多种。
在一些实施方式中，电解液中还包括添加剂。例如添加剂可以包括负极成膜添加剂，也可以包括正极成膜添加剂，还可以包括能够改善电池某些性能的添加剂，例如改善电池过充性能的添加剂、改善电池高温性能的添加剂、改善电池低温性能的添加剂等。
在一些实施方式中，本申请的二次电池为锂离子二次电池。
可以按照本领域常规方法制备二次电池，例如将正极极片、隔离膜、负极极片按顺序卷绕(或叠片)，使隔离膜处于正极极片与负极极片之间起到隔离的作用，得到电芯，将电芯置于外包装中，注入电解液并封口，得到二次电池。
本申请实施例对二次电池的形状没有特别的限制，其可以是圆柱形、方形或其他任意的形状。如图1是作为一个示例的方形结构的二次电池5。
在一些实施例中，二次电池可包括外包装。该外包装用于封装正极极片、负极极片和电解液。
在一些实施例中，参照图2，外包装可包括壳体51和盖板53。其中，壳体51可包括底板和连接于底板上的侧板，底板和侧板围合形成容纳腔。壳体51具有与容纳腔连通的开口，盖板53能够盖设于所述开口，以封闭所述容纳腔。
正极极片、负极极片和隔离膜可经卷绕工艺或叠片工艺形成电极组件52。电极组件52封装于所述容纳腔。电解液浸润于电极组件52中。二次电池5所含电极组件52的数量可以为一个或多个，可根据需求来调节。
在一些实施例中，二次电池的外包装可以是硬壳，例如硬塑料壳、铝壳、钢壳等。二次电池的外包装也可以是软包，例如袋式软包。软包的材质可以是塑料，如可包括聚丙烯(PP)、聚对苯二甲酸丁二醇酯(PBT)、聚丁二酸丁二醇酯(PBS)等中的一种或多种。
在一些实施例中，二次电池可以组装成电池模块，电池模块所含二次电池的数量可以为多个，具体数量可根据电池模块的应用和容量来调节。
图3是作为一个示例的电池模块4。在电池模块4中，多个二次电池5可以是沿电池模块4的长度方向依次排列设置。当然，也可以按照其他任意的方式进行排布。进一步可以通过紧固件将该多个二次电池5进行固定。
可选地，电池模块4还可以包括具有容纳空间的外壳，多个二次电池5容纳于该容纳空间。
在一些实施例中，上述电池模块还可以组装成电池包，电池包所含电池模块的数量可以根据电池包的应用和容量进行调节。
图4和图5是作为一个示例的电池包1。在电池包1中可以包括电池箱和设置于电池箱中的多个电池模块4。电池箱包括上箱体2和下箱体3，上 箱体2能够盖设于下箱体3，并形成用于容纳电池模块4的封闭空间。多个电池模块4可以按照任意的方式排布于电池箱中。
用电装置
本申请还提供一种用电装置，所述用电装置包括所述的二次电池、电池模块、或电池包中的至少一种。所述二次电池、电池模块或电池包可以用作所述装置的电源，也可以作为所述装置的能量存储单元。所述装置可以但不限于是手机、笔记本电脑等移动设备，或纯电动车、混合动力电动车、插电式混合动力电动车、电动自行车、电动踏板车、电动高尔夫球车、电动卡车等电动车辆，或者电气列车、船舶及卫星、储能系统等。
所述装置可以根据其使用需求来选择二次电池、电池模块或电池包。
图6是作为一个示例的装置。该用电装置6为纯电动车、混合动力电动车、或插电式混合动力电动车等。为了满足该装置对二次电池的高功率和高能量密度的需求，可以采用电池包或电池模块。
作为另一个示例的装置可以是手机、平板电脑、笔记本电脑等。该装置通常要求轻薄化，可以采用二次电池作为电源。
以下结合实施例进一步说明本申请的有益效果。
具体实施例
为了使本申请所解决的技术问题、技术方案及有益效果更加清楚，以下将结合实施例和附图进行进一步详细说明。显然，所描述的实施例仅仅是本申请一部分实施例，而不是全部的实施例。以下对至少一个示例性实施例的描述实际上仅仅是说明性的，决不作为对本申请及其应用的任何限制。基于本申请中的实施例，本领域普通技术人员在没有付出创造性劳动前提下所获得的所有其他实施例都属于本申请保护的范围。
本申请的实施例中所用的材料均可以通过商购获得。
一、正极活性材料的制备及性能测试
1、正极活性材料的制备
正极活性材料1-5
S1：将富锂锰基前驱体均匀分散在溶剂中，然后分别将钼盐(钼酸铵)和镧盐(硝酸镧)溶解到溶剂中制成溶液；
S2：在水浴条件下将步骤S1中的钼盐(钼酸铵)以及镧盐(硝酸镧)溶液滴加到前驱体的分散液中并调节溶液pH为9，然后将溶液在常温下搅拌4h后转移至反应釜中，在100-200℃下水热反应8-12h，待反应釜冷却至室温后，得到使钼盐与镧盐生成钼酸镧(La 2Mo 2O 9)原位沉积到前驱体表面；
S3：将步骤S2得到的前驱体产物用去离子水洗涤并真空干燥后，与锂盐(碳酸锂)球磨混合，先在300-500℃下进行预煅烧2h，随后在700-900℃下高温烧结10-20h，自然冷却至室温，得到表面包覆的富锂锰基正极材料。富锂锰基正极材料的表面包覆有氧离子导体La 2Mo 2O 9和锂离子导体LiLaO 2和Li 2MoO 4的复合包覆层。具体参数如表1所示。
说明：表1中Li/Me是指步骤S3中加入的锂盐(碳酸锂)中的锂元素与步骤S3中加入的前驱体产物中所有金属元素的摩尔比。可理解，步骤S3中加入的前驱体产物中所有金属元素的物质的量可通过元素测试得到。
2、正极活性材料的性能测试
1)内核材料的分子结构和Dv50粒径测试。
Dv50指的是在体积分布中50％所对应的粒度尺寸。作为示例，Dv50可以参照GB/T 19077-2016粒度分布激光衍射法，采用激光粒度分析仪方便地测定，如英国马尔文仪器有限公司的Mastersizer 2000E型激光粒度分析仪。
2)钼和镧掺杂进入内核材料的厚度测试，表1中简称为掺杂厚度。
钼和镧掺杂进入内核材料的厚度可以通过公知的离子抛光断面(CP)元素面扫描和线扫描分析来表征有钼和镧掺杂进入内核材料的厚度。
3)包覆层的La:Mo的摩尔比测试、La和Mo的含量测试、IO 2 2-/IO 2-测 试。
包覆层的La:Mo的摩尔比、La和Mo的含量测试可以分别采用公知的X射线能谱仪(EDS)进行面扫分析和电感耦合等离子体发射光谱仪(ICP-AES)进行测试分析。IO 2 2-/IO 2-可以采用公知的X射线光电子能谱(XPS)来分析，其中IO 2 2-为X射线光电子能谱测试中531eV的氧空位的峰强值，IO 2-为对应于X射线光电子能谱测试中529eV的晶格氧的峰强值。
正极活性材料1-5的部分原料和性能测试结果如下表1所示：
其中包覆层的厚度为所有包覆层的总厚度。
表1
Figure PCTCN2022097507-appb-000001
其中，内核材料1-5分别为0.35Li 2MnO 3·0.65LiNi 0.46Co 0.08Mn 0.46O 2、0.35Li 2MnO 3·0.65LiNi 0.45Co 0.08Mn 0.46Mg 0.01O 2、0.35Li 2MnO 3·0.65LiNi 0.45Co 0.08Mn 0.46Al 0.01O 2、0.35Li 2MnO 3·0.65LiNi 0.45Co 0.08Mn 0.46Ti 0.01O 2、0.35Li 2MnO 3·0.65LiNi 0.45Co 0.08Mn 0.46V 0.01O 2。
实施例6：
将富锂锰基正极材料0.35Li 2MnO 3·0.65LiNi 0.45Co 0.08Mn 0.46Al 0.01O 2和氧 离子导体La 2Mo 2O 9和锂离子导体LiLaO 2进行固相混合，混合完成后，在空气气氛中400℃下进行预煅烧2h，随后在800℃保温12h，即得改性后富锂锰基正极材料；
在实施例7-13中，除了如表2所示变更各原料的组成以外，采用与实施例6相同的制备方法。
正极活性材料6-13的性能测试结果如下表2所示：
表2
Figure PCTCN2022097507-appb-000002
二、正极极片的制备
正极极片1-13
将上述正极活性材料1-13、导电炭黑(SP)、聚偏氟乙烯(PVDF)按照质量比96.8：2.2:1混合，溶于N-甲基吡咯烷酮(NMP)中，合浆后制得正极浆料涂覆在宽幅400mm的铝箔上烘干，冷压，裁切得到正极极片。
三、电池的制备
1.正极极片：使用上述制得的正极极片1-13。
2.隔离膜：使用聚乙烯(PE)多孔聚合隔膜作为隔离膜
3.负极极片：将石墨、粘结剂丁苯橡胶(SBR)、粘结剂聚丙烯酸(PAA)、分散剂(CMC-Na)以及导电炭黑(Super-P，SP)、碳纳米管(CNT)按95％： 2％：1％：1％：0.7％：0.3％的重量比在适量的去离子水中充分搅拌混合，制备成负极浆料。再将负极浆料涂布至6μm厚的铜箔上，进行干燥和冷压形成负极活性材料层，裁切成负极极片。
4.电解液：将碳酸乙烯酯(EC)、碳酸甲乙酯(EMC)、碳酸二乙酯(DEC)按照体积比3:6:1进行混合后，将充分干燥的锂盐(LiPF6)按照1mol/L的比例溶于混合有机溶剂中。得到所需电解液。
5.全电池组装：将上述正极极片、隔离膜、负极极片按顺序叠好，使隔离膜处于正负极中间起到隔离的作用，并卷绕得到裸电芯。将裸电芯置于外包装铝壳中，将上述制备好的电解液注入到高温烘干后的干电池中，经过真空封装、静置、化成、整形等工序，获得锂离子二次电池1-13，如表3所示。
四、电池性能评估
各电池1-13的性能评估均按以下方法实施。
1、首次放电效率
将注液后的电池1-13在45℃条件下以0.02C的恒流充电至3.4V，静置5min，再以0.1C恒流充电至3.75V，记录容量为Z1，然后进行排气和二封，将二封后的电池置于25℃条件中，0.33C恒流充电至4.5V，恒压充电至0.02C，静置5分钟，记录容量为Z2；然后0.33C放电至2.0V，记录容量为D1。
首次效率的计算公式如下：首次效率＝D1/(Z1+Z2)。
2、放电容量测试
在25℃的恒温环境下，在2.0V-4.5V下，按照0.33C充电至4.5V，然后在4.5V下恒压充电至电流为0.05C，静置5min，然后按照0.33C放电至2.0V，记录0.33C放电倍率时该锂离子电池的容量具体结果(即为0.33C放电容量)；静置5min，按照0.33C充电至4.5V，然后在4.5V下恒压充电至电流为0.05C，静置5min，然后按照0.5C放电至2.0V，记录0.5C放电倍率时该锂离子电池的容量具体结果(即为0.5C放电容量)。
3、循环性能测试：
1)在25℃的恒温环境下，进行第一次充电和放电，在0.5C(即2小时内完全放掉理论容量的电流值)的充电电流下进行恒流和恒压充电(充电至电流为0.05C)，直到上限电压达到4.46V，静置5分钟后，在0.5C的放电电流下进行恒流放电，直到最终电压为2.3V，记录首次循环的放电容量；而后进行持续充放电循环。
25℃全电循环500cls容量保持率，即第500次循环的容量保持率＝(第500次循环的放电容量/首次循环的放电容量)×100％。
2)在45℃的恒温环境下，进行第一次充电和放电，在0.5C(即2小时内完全放掉理论容量的电流值)的充电电流下进行恒流和恒压充电(充电至电流为0.05C)，直到上限电压达到4.46V，静置5分钟后，在0.5C的放电电流下进行恒流放电，直到最终电压为2.3V，记录首次循环的放电容量；而后进行持续充放电循环。
45℃全电循环500cls容量保持率，即第500次循环的容量保持率＝(第500次循环的放电容量/首次循环的放电容量)×100％。
表3
Figure PCTCN2022097507-appb-000003
由表3可知，对比例1中的正极活性材料的包覆层中不含有氧离子导体，对比例2的包覆层中不含有锂离子导体，各实施例中的正极活性材料的包覆层同时含有氧离子导体及锂离子导体；相比于对比例，各实施例制得的二次电池同时具有较佳的首次放电效率、循环性能和倍率性能。
进一步地，通过实施例1-5和实施例6-11可知，实施例1-5中采用特定种类的氧离子导体及锂离子导体协同，其制得的二次电池能够同时具有更好的首次放电效率、循环性能和倍率性能。
以上所述，仅为本申请的具体实施方式，但本申请的保护范围并不局限于此，任何熟悉本技术领域的技术人员在本申请揭露的技术范围内，可轻易想到各种等效的修改或替换，这些修改或替换都应涵盖在本申请的保护范围之内。因此，本申请的保护范围应以权利要求的保护范围为准。

Claims (22)

  1. 一种正极活性材料，其特征在于，包括：
    内核材料，包含有富锂锰基正极材料；
    包覆层，包覆在所述内核材料的外表面，所述包覆层包含有氧离子导体和锂离子导体。
  2. 如权利要求1所述的正极活性材料，其特征在于，所述氧离子导体包括La 2Mo 2O 9及萤石型氧离子导体中的至少一种。
  3. 如权利要求2所述的正极活性材料，其特征在于，所述萤石型氧离子导体包括ZrO 2、CeO 2及GeO 2中的至少一种。
  4. 如权利要求1至3任一项所述的正极活性材料，其特征在于，所述锂离子导体包括LiLaO 2、Li 2MoO 4、Li 3PO 4，Li 3BO 3及LiTaO 3中的至少一种。
  5. 如权利要求1至4任一项所述的正极活性材料，其特征在于，所述氧离子导体包含La 2Mo 2O 9；所述锂离子导体包含LiLaO 2和Li 2MoO 4。
  6. 如权利要求5所述的正极活性材料，其特征在于，所述包覆层中镧原子和钼原子的摩尔比为1：(1.02-1.1)；可选为1：(1.02-1.05)。
  7. 如权利要求5至6任一项所述的正极活性材料，其特征在于，所述包覆层中钼原子的含量为300-5000ppm；和/或，
    所述包覆层中镧原子的含量为500-5000ppm。
  8. 如权利要求5至7任一项所述的正极活性材料，其特征在于，所述包覆层中钼原子的含量为1000-4000ppm；和/或，
    所述包覆层中镧原子的含量为1000-3000ppm。
  9. 如权利要求5至8任一项所述的正极活性材料，其特征在于，所述内核材料的表面掺杂有镧原子和钼原子。
  10. 如权利要求9所述的正极活性材料，其特征在于，所述内核材料掺杂有镧原子和钼原子的表面厚度不大于3μm；可选为不大于2μm。
  11. 如权利要求1至10任一项所述的正极活性材料，其特征在于，所述包覆层的厚度为0.01-4μm。
  12. 如权利要求1至11任一项所述的正极活性材料，其特征在于，所述包覆层的厚度为0.02-1μm。
  13. 如权利要求1至12任一项所述的正极活性材料，其特征在于，所述包覆层中IO 2 2-/IO 2-的峰强比为0.5-1；可选为0.7-0.9；
    其中，IO 2 2-为X射线光电子能谱测试中531eV的氧空位的峰强值，IO 2-为对应于X射线光电子能谱测试中529eV的晶格氧的峰强值。
  14. 如权利要求1至13任一项所述的正极活性材料，其特征在于，所述富锂锰基正极材料的分子式为xLi 2MnO 3·(1-x)LiNi yCo zMn aM 1-y-z-aO 2，
    其中0<x<1，0≤y≤1，0≤z≤1，0≤a≤1，0<y+z+a≤1；M为Mg、B、Al、V、Ti、Zr、Sn和Mo中至少一种。
  15. 如权利要求1至14任一项所述的正极活性材料，其特征在于，所述富锂锰基正极材料的颗粒类型为二次颗粒、单晶或类单晶；和/或，
    所述富锂锰基正极材料的比表面积＜2.0m 2/g，可选0.1-1m 2/g；
    所述富锂锰基正极材料的Dv50粒径为1-20μm；可选3-15μm。
  16. 一种如权利要求1至15任一项所述的正极活性材料的制备方法，其特征在于，包括如下步骤：
    在所述内核材料的表面形成所述包覆层。
  17. 如权利要求16所述的制备方法，其特征在于，所述氧离子导体包含La 2Mo 2O 9，所述锂离子导体包含LiLaO 2和Li 2MoO 4；所述制备方法包括如下步骤：
    将钼盐、镧盐及富锂锰基前驱体在溶剂中混合，并于100-200℃下进行水热反应8-12h，得到表面原位沉积有La 2Mo 2O 9的富锂锰基前驱体；
    将所述表面原位沉积有La 2Mo 2O 9的富锂锰基前驱体与锂盐混合后，进行煅烧处理，得到氧离子导体和锂离子导体复合包覆的正极活性材料。
  18. 如权利要求17所述的制备方法，其特征在于，所述富锂锰基前驱体为Ni bCo cMn dM (1-b-c-d)(OH) 2，
    其中0＜b＜0.4，0≤c≤0.05，0.6≤d＜1，M为Mg、B、Al、V、Ti、Zr、Sn和Mo中至少一种。
  19. 如权利要求17至18任一项所述的制备方法，其特征在于，所述溶剂为水、乙醇、甲醇及乙二醇中的至少一种；和/或，
    所述钼盐为钼酸铵、钼酸钠及钼酸钾中的至少一种；和/或，
    所述镧盐为氯化镧及硝酸镧中的至少一种；和/或，
    所述锂盐为碳酸锂、氢氧化锂及醋酸锂中的至少一种；和/或，
    所述锂盐中锂元素和所述表面原位沉积有La 2Mo 2O 9的富锂锰基前驱体中的所有金属元素的摩尔比为1：(1.1-1.8)，可选为1：(1.1-1.5)；和/或，
    所述水热反应的pH值为8-10；和/或，
    所述煅烧处理的气氛为空气；和/或，
    所述煅烧处理的步骤包括：先于300-500℃下进行预煅烧2-5h，然后于700-900℃下烧结10-20h。
  20. 一种正极极片，其特征在于，包括：
    正极集流体；及
    正极活性材料层，所述正极活性材料层位于所述正极集流体的表面，所述正极活性材料层的组分包括如权利要求1至15任一项所述的正极活性材料或如权利要求16至19任一项所述的制备方法制得的正极活性材料。
  21. 一种二次电池，其特征在于，包括如权利要求20所述的正极极片。
  22. 一种用电装置，其特征在于，包括选自权利要求21所述的二次电池。
PCT/CN2022/097507 2022-06-08 2022-06-08 正极活性材料及其制备方法、极片、二次电池及用电装置 WO2023236068A1 (zh)

Priority Applications (6)

Application Number Priority Date Filing Date Title
CN202280062469.0A CN117941101A (zh) 2022-06-08 2022-06-08 正极活性材料及其制备方法、极片、二次电池及用电装置
JP2024503681A JP2024527841A (ja) 2022-06-08 2022-06-08 正極活物質及びその製造方法、極板、二次電池及び電力消費装置
KR1020247001796A KR20240023133A (ko) 2022-06-08 2022-06-08 캐소드 활물질 및 그의 제조 방법, 극판, 이차 전지 및 전기 장치
PCT/CN2022/097507 WO2023236068A1 (zh) 2022-06-08 2022-06-08 正极活性材料及其制备方法、极片、二次电池及用电装置
EP22942944.4A EP4333121A4 (en) 2022-06-08 2022-06-08 POSITIVE ELECTRODE ACTIVE MATERIAL AND PRODUCTION METHOD THEREOF, ELECTRODE PLATE, SECONDARY BATTERY AND ELECTRICAL DEVICE
US18/412,601 US20240199441A1 (en) 2022-06-08 2024-01-15 Positive active material, method for preparing same, electrode plate, secondary battery, and electrical device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/CN2022/097507 WO2023236068A1 (zh) 2022-06-08 2022-06-08 正极活性材料及其制备方法、极片、二次电池及用电装置

Related Child Applications (1)

Application Number Title Priority Date Filing Date
US18/412,601 Continuation US20240199441A1 (en) 2022-06-08 2024-01-15 Positive active material, method for preparing same, electrode plate, secondary battery, and electrical device

Publications (1)

Publication Number Publication Date
WO2023236068A1 true WO2023236068A1 (zh) 2023-12-14

Family

ID=89117367

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2022/097507 WO2023236068A1 (zh) 2022-06-08 2022-06-08 正极活性材料及其制备方法、极片、二次电池及用电装置

Country Status (6)

Country Link
US (1) US20240199441A1 (zh)
EP (1) EP4333121A4 (zh)
JP (1) JP2024527841A (zh)
KR (1) KR20240023133A (zh)
CN (1) CN117941101A (zh)
WO (1) WO2023236068A1 (zh)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN117594783A (zh) * 2024-01-18 2024-02-23 国联汽车动力电池研究院有限责任公司 一种层状复合型富锂锰基正极材料及其制备方法和应用

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20140302392A1 (en) * 2013-04-09 2014-10-09 Envia Systems, Inc. Uniform stabilization nanocoatings for lithium rich complex metal oxides and atomic layer deposition for forming the coating
CN106745261A (zh) * 2016-11-28 2017-05-31 合肥学院 一种合成固体氧化物燃料电池电解质材料纳米钼酸镧的方法
CN109256531A (zh) * 2017-07-14 2019-01-22 中国科学院宁波材料技术与工程研究所 具有复合包覆层的掺杂钴酸锂及其制备方法和应用
CN109560265A (zh) * 2018-11-02 2019-04-02 中国电力科学研究院有限公司 一种有效抑制富锂锰基正极材料氧流失的包覆方法
CN113823786A (zh) * 2021-09-30 2021-12-21 中国矿业大学(北京) 一种改性富锂锰基正极材料及其制备方法

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2015083900A1 (ko) * 2013-12-02 2015-06-11 주식회사 엘앤에프신소재 리튬 이차 전지용 양극 활물질, 이의 제조방법 및 이를 포함하는 리튬 이차 전지
KR101925105B1 (ko) * 2016-05-25 2018-12-04 주식회사 엘 앤 에프 양극 활물질, 이의 제조방법 및 이를 포함하는 리튬 이차 전지
CN111434618B (zh) * 2020-01-17 2022-07-22 蜂巢能源科技有限公司 无钴层状正极材料及制备方法、锂离子电池

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20140302392A1 (en) * 2013-04-09 2014-10-09 Envia Systems, Inc. Uniform stabilization nanocoatings for lithium rich complex metal oxides and atomic layer deposition for forming the coating
CN106745261A (zh) * 2016-11-28 2017-05-31 合肥学院 一种合成固体氧化物燃料电池电解质材料纳米钼酸镧的方法
CN109256531A (zh) * 2017-07-14 2019-01-22 中国科学院宁波材料技术与工程研究所 具有复合包覆层的掺杂钴酸锂及其制备方法和应用
CN109560265A (zh) * 2018-11-02 2019-04-02 中国电力科学研究院有限公司 一种有效抑制富锂锰基正极材料氧流失的包覆方法
CN113823786A (zh) * 2021-09-30 2021-12-21 中国矿业大学(北京) 一种改性富锂锰基正极材料及其制备方法

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See also references of EP4333121A4

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN117594783A (zh) * 2024-01-18 2024-02-23 国联汽车动力电池研究院有限责任公司 一种层状复合型富锂锰基正极材料及其制备方法和应用
CN117594783B (zh) * 2024-01-18 2024-05-24 国联汽车动力电池研究院有限责任公司 一种层状复合型富锂锰基正极材料及其制备方法和应用

Also Published As

Publication number Publication date
EP4333121A4 (en) 2024-09-04
CN117941101A (zh) 2024-04-26
JP2024527841A (ja) 2024-07-26
EP4333121A1 (en) 2024-03-06
KR20240023133A (ko) 2024-02-20
US20240199441A1 (en) 2024-06-20

Similar Documents

Publication Publication Date Title
CN113875051B (zh) 二次电池、其制备方法及含有该二次电池的装置
WO2021189424A1 (zh) 二次电池和含有该二次电池的装置
WO2023015429A1 (zh) 复合金属氧化物材料及其制备方法、正极极片、二次电池、电池模块、电池包和用电装置
US20230119115A1 (en) Positive-electrode active material and manufacturing method thereof, secondary battery, battery module, battery pack, and apparatus
US20230343938A1 (en) Positive electrode active material and preparation method therefor, positive electrode plate comprising same, secondary battery, and power consuming device
US20200227741A1 (en) Cathode material and electrochemical device including cathode material
US20230369591A1 (en) Negative-electrode active material and preparation method thereof, secondary battery, and battery module, battery pack, and apparatus containing such secondary battery
CN113875047B (zh) 二次电池及其制备方法、含有该二次电池的装置
WO2023040358A1 (zh) 三元前驱体及其制备方法，三元正极材料以及用电装置
WO2023240544A1 (zh) 正极材料及其制备方法、具备其的二次电池
KR20230042208A (ko) 고-니켈 양극 활물질, 이의 제조 방법, 이를 포함하는 리튬 이온 전지, 전지 모듈, 전지 팩 및 전기 장치
US20240199441A1 (en) Positive active material, method for preparing same, electrode plate, secondary battery, and electrical device
WO2021258275A1 (zh) 二次电池和包含该二次电池的装置
WO2023078047A1 (zh) 正极活性材料、其制备方法、包括其的锂离子电池、电池模块、电池包和用电装置
US20230119054A1 (en) Silicon-oxygen compound, secondary battery using it, and related battery module, battery pack and device
US20220102788A1 (en) Secondary battery and apparatus containing the same
WO2022257146A1 (zh) 复合正极材料及其制备方法、二次电池及包含该二次电池的电池组和用电装置
KR20240019315A (ko) 개질 양극재, 이의 제조 방법, 양극 시트, 이차 전지, 전지 모듈, 전지 팩 및 전기 장치
WO2023197240A1 (zh) 正极活性材料、二次电池、电池模块、电池包和用电装置
JP7507257B2 (ja) 正極活物質およびこれを含むリチウム二次電池
WO2024011621A1 (zh) 磷酸锰铁锂正极活性材料及其制备方法、正极极片、二次电池及用电装置
WO2024059980A1 (zh) 含锂镍锰复合氧化物、其制备方法以及包含其的正极极片、二次电池及用电装置
WO2023193231A1 (zh) 一种二次电池、相应正极活性材料的制备方法、电池模块、电池包和用电装置
WO2024065647A1 (zh) 正极活性材料及其制备方法、二次电池和用电装置
WO2024000095A1 (zh) 负极极片、二次电池、电池模组、电池包及用电装置

Legal Events

Date Code Title Description
WWE Wipo information: entry into national phase

Ref document number: 2022942944

Country of ref document: EP

ENP Entry into the national phase

Ref document number: 2022942944

Country of ref document: EP

Effective date: 20231127

ENP Entry into the national phase

Ref document number: 20247001796

Country of ref document: KR

Kind code of ref document: A

WWE Wipo information: entry into national phase

Ref document number: 1020247001796

Country of ref document: KR

ENP Entry into the national phase

Ref document number: 2024503681

Country of ref document: JP

Kind code of ref document: A

121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 22942944

Country of ref document: EP

Kind code of ref document: A1

WWE Wipo information: entry into national phase

Ref document number: 202280062469.0

Country of ref document: CN