WO2021196732A1 - 正极材料及其制备方法、锂离子电池和电动汽车 - Google Patents

正极材料及其制备方法、锂离子电池和电动汽车 Download PDF

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WO2021196732A1
WO2021196732A1 PCT/CN2020/136071 CN2020136071W WO2021196732A1 WO 2021196732 A1 WO2021196732 A1 WO 2021196732A1 CN 2020136071 W CN2020136071 W CN 2020136071W WO 2021196732 A1 WO2021196732 A1 WO 2021196732A1
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lithium
positive electrode
hours
cathode material
atmosphere
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PCT/CN2020/136071
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English (en)
French (fr)
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朱金鑫
王鹏飞
赵硕
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蜂巢能源科技有限公司
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Priority to US17/793,632 priority Critical patent/US20230048254A1/en
Priority to EP20929275.4A priority patent/EP4024515A4/en
Publication of WO2021196732A1 publication Critical patent/WO2021196732A1/zh

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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
    • C—CHEMISTRY; METALLURGY
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    • 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
    • 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
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    • H01M4/36—Selection of substances as active materials, active masses, active liquids
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    • H01M4/364—Composites as mixtures
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    • 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
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    • 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
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    • 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
    • H01M4/624—Electric conductive fillers
    • H—ELECTRICITY
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    • 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
    • H01M4/628—Inhibitors, e.g. gassing inhibitors, corrosion inhibitors
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2002/00—Crystal-structural characteristics
    • C01P2002/50—Solid solutions
    • 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
    • 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
    • C01P2006/40—Electric properties
    • H—ELECTRICITY
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    • 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
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M2220/00—Batteries for particular applications
    • H01M2220/20—Batteries in motive systems, e.g. vehicle, ship, plane
    • 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 disclosure relates to the technical field of lithium-ion batteries, such as positive electrode materials and preparation methods thereof, lithium-ion batteries and electric vehicles.
  • lithium-rich manganese-based materials also have many problems, such as poor rate performance and low cycle capacity retention, and the manganese content in the material reaches more than 50%.
  • Manganese metal element has very poor metal conductivity, which reduces the intrinsic properties of the material.
  • the high ionic conductivity makes the material unable to quickly insert and insert lithium ions during high-current charging and discharging.
  • researchers have done a lot of work, but the current improvement measures can achieve limited improvement effects, and can only unilaterally improve the magnification or cycle performance.
  • the present disclosure provides a positive electrode material and a preparation method thereof, a lithium ion battery and an electric vehicle.
  • a positive electrode material includes: matrix particles, the material forming the matrix particles includes lithium-rich manganese-based materials, lithium nickel cobalt manganate, lithium nickel cobalt aluminate, iron phosphate At least one of lithium, lithium manganate, lithium nickel cobalt manganese aluminate, and lithium nickel manganese oxide; and a shell, the shell covering at least a part of the outer surface of the base particles, and the material forming the shell includes At least one of lithium titanium phosphate, lithium aluminum germanium phosphate, and lithium aluminum titanium phosphate.
  • lithium titanium phosphate, lithium germanium aluminum phosphate, or lithium titanium aluminum phosphate coats the base particles, that is, the surface of the base particles is modified, and the obtained cathode material has high ion conductivity and low electrolyte reactivity. It can effectively improve the stability of the surface structure of the matrix particles, and significantly improve its magnification and cycle performance.
  • the thickness of the shell is 0-500 nm and is not zero.
  • the thickness of the shell is 0-200 nm and is not zero.
  • the thickness of the shell is 0-100 nm and is not zero.
  • the particle size distribution of the positive electrode material is 1-17 microns, and in one embodiment, it is 4-15 microns.
  • the particle size distribution is the range of the particle size distribution of the positive electrode material.
  • the material forming the matrix particles is the lithium-rich manganese-based material, and the chemical composition of the cathode material is:
  • a+b+c 1, 0 ⁇ a ⁇ 0.6, 0 ⁇ b ⁇ 0.5, 0 ⁇ c ⁇ 0.05, 0 ⁇ 0.04, 0 ⁇ 0.5, 0.005 ⁇ 0.02, 0 ⁇ ' ⁇ 0.04, -0.02 ⁇ ” ⁇ 1, 0.005 ⁇ ' ⁇ 0.02, 0 ⁇ 0.5,
  • M is at least one element of Ni, Co, Mn, Al, Mg, Ti, Zr, Zn, Ca, B, Ce, Cr, etc.,
  • M' is at least one element of Ti and Ge.
  • the cathode material includes at least one of the following:
  • the cathode material satisfies at least one of the following conditions:
  • the specific discharge capacity at a rate of 0.1C is greater than or equal to 280 mAh/g, and in one embodiment, greater than or equal to 300 mAh/g;
  • the 1C rate discharge specific capacity is greater than or equal to 220 mAh/g, in one embodiment, greater than or equal to 240 mAh/g;
  • the capacity retention rate after 50 cycles of charge and discharge is greater than or equal to 85%, and in one embodiment, greater than or equal to 86%.
  • a method for preparing the aforementioned positive electrode material includes: ball milling a mixture of matrix particles and shell raw materials for 1-10 hours to obtain a mixed material. It is calcined at -900° C. in an O 2 /N 2 atmosphere for 1-12 hours to obtain a positive electrode material, wherein the shell raw material is nano-lithium titanium phosphate, nano-lithium germanium aluminum phosphate, or nano-lithium titanium aluminum phosphate.
  • This method can quickly and effectively obtain the aforementioned positive electrode material, with simple steps and easy operation, and the obtained positive electrode material has high ionic conductivity and low electrolyte reactivity, which can effectively improve the stability of the surface layer structure of the matrix particles.
  • the surface-modified matrix particles can significantly improve its magnification and cycle performance.
  • the matrix particles are prepared by the following steps: calcining the precursor material at 300-800° C. in an O 2 /N 2 atmosphere for 4-12 hours to obtain the first calcined product.
  • the calcined product is mixed with a lithium source, and the obtained mixture is calcined at 600-950°C in an O 2 /N 2 atmosphere for 10-24 hours to obtain the matrix particles.
  • the matrix particles are prepared by the following steps: calcining the precursor material at 300-800°C under an O 2 /N 2 atmosphere for 4-12 hours to obtain the first calcined product, and The first calcined product is mixed with the lithium source, and the resulting mixture is calcined at 600-950°C and O 2 /N 2 atmosphere for 10-24 hours to obtain a second calcined product; combining the second calcined product with nano-TiO After the mixture of 2 is ball milled for 2-8 hours, it is calcined at 750-850°C in an O 2 /N 2 atmosphere for 4-16 hours to obtain the matrix particles.
  • a lithium ion battery is provided, and the lithium ion battery includes the aforementioned positive electrode material.
  • the rate performance and cycle performance of the lithium ion battery are better, and the energy density is higher.
  • An embodiment of the present disclosure provides an electric vehicle, which includes the aforementioned lithium ion battery.
  • the electric vehicle using the above-mentioned lithium-ion battery has better endurance.
  • FIG. 1 is the first charging and discharging curve of the positive electrode material in the comparative example of the present disclosure and Example 1.
  • FIG. 1 is the first charging and discharging curve of the positive electrode material in the comparative example of the present disclosure and Example 1.
  • FIG. 2 is the first charging and discharging curve of the positive electrode material in the comparative example and the embodiment 2 of the present disclosure.
  • FIG. 3 is the first charge and discharge curve of the positive electrode material in the comparative example of the present disclosure and Example 3.
  • FIG. 3 is the first charge and discharge curve of the positive electrode material in the comparative example of the present disclosure and Example 3.
  • FIG. 4 is the rate performance test result of the positive electrode material in the comparative example of the present disclosure and Example 1.
  • FIG. 4 is the rate performance test result of the positive electrode material in the comparative example of the present disclosure and Example 1.
  • FIG. 5 is the rate performance test result of the positive electrode material in the comparative example of the present disclosure and Example 2.
  • FIG. 5 is the rate performance test result of the positive electrode material in the comparative example of the present disclosure and Example 2.
  • FIG. 6 is the rate performance test result of the positive electrode material in the comparative example of the present disclosure and Example 3.
  • FIG. 6 is the rate performance test result of the positive electrode material in the comparative example of the present disclosure and Example 3.
  • FIG. 7 is a test result of the cycle performance of the positive electrode material in the comparative example of the present disclosure and Example 1.
  • FIG. 7 is a test result of the cycle performance of the positive electrode material in the comparative example of the present disclosure and Example 1.
  • FIG. 8 is a test result of the cycle performance of the positive electrode material in the comparative example of the present disclosure and the embodiment 2.
  • FIG. 8 is a test result of the cycle performance of the positive electrode material in the comparative example of the present disclosure and the embodiment 2.
  • FIG. 9 is a test result of the cycle performance of the positive electrode material in the comparative example of the present disclosure and Example 3.
  • FIG. 9 is a test result of the cycle performance of the positive electrode material in the comparative example of the present disclosure and Example 3.
  • An embodiment of the present disclosure provides a positive electrode material.
  • the positive electrode material includes base particles.
  • the material forming the base particles includes lithium-rich manganese-based materials, lithium nickel cobalt manganese oxide, lithium nickel cobalt aluminate, and lithium iron phosphate. , At least one of lithium manganate, lithium nickel cobalt manganese aluminate and lithium nickel manganese oxide; and a shell, the shell covering at least a part of the outer surface of the base particles, and the material forming the shell includes lithium titanium phosphate, At least one of lithium aluminum germanium phosphate and lithium aluminum titanium phosphate.
  • the positive electrode material obtained by surface modification or coating of active material has high ionic conductivity and low electrolyte reactivity, which can effectively improve the stability of the surface structure of the matrix particles while undergoing surface modification The matrix particles can significantly improve its rate and cycle performance.
  • the material forming the matrix particles is a lithium-rich manganese-based material (also referred to as a lithium-rich manganese-based cathode material).
  • the transition metal ions at the octahedral site of the transition metal layer in the crystal structure of the lithium-rich manganese-based cathode material migrate to the octahedral site of the lithium layer through the tetrahedral site at the intermediate position ; Transition metal ions can almost reversibly shuttle between the octahedral site of the transition metal layer and the tetrahedral site in the middle position (under 100% SOC conditions, its content reaches about 4%); after reaching the tetrahedral site of the lithium layer,
  • the transition metal ions can basically only migrate to the octahedral sites of the lithium layer in one direction, and this lithium/transition metal ion mixing may be an important reason for the poor cycle stability of the material
  • the lithium-rich manganese-based cathode material has inherent defects, which causes it to exhibit a serious problem of cycle capacity retention.
  • the coated shell can fit well with the structure of the matrix particles, can provide a good lithium ion migration channel, and can improve the stability of the electrochemical structure of the matrix particles. , It can improve the ionic conductivity of the material while improving the cycle stability, and overcome the problem that the existing modified lithium-rich manganese-based cathode materials can only unilaterally improve the rate performance or cycle performance.
  • the lithium-rich manganese-based cathode material used may include nickel cobalt manganese carbonate or nickel cobalt manganese hydroxide. In one embodiment, it may be Ni 0.2 Co 0.2 Mn 0.6 CO 3 , Ni 0.3 Co 0.2 Mn 0.5 CO 3 , Ni 0.3 Co 0.2 Mn 0.5 (OH) 2 , Ni 0.2 Co 0.1 Mn 0.7 CO 3 , Ni 0.2 Co 0.1 Mn 0.7 (OH) 2 and so on.
  • the material forming the above-mentioned housing includes at least one of lithium titanium phosphate, lithium aluminum germanium phosphate, and lithium aluminum titanium phosphate.
  • the casing material has higher ionic conductivity, which can effectively improve the migration rate of lithium ions at the interface; in addition, the reaction activity between the casing material and the electrolyte is low, which can significantly reduce the corrosion of the electrolyte to the cathode material. Enhance the structural stability of the cathode material particles during cycling.
  • the aforementioned shell material can also function as a buffer layer, has dual functions, and can better improve the electrochemical performance of the positive electrode material.
  • the thickness of the housing may be 0-500nm and not 0, in an embodiment it may be 0-200nm but not 0, in an embodiment it may be 0-100nm but not 0, For example, 5nm, 10nm, 15nm, 20nm, 25nm, 30nm, 35nm, 40nm, 45nm, 50nm, 55nm, 60nm, 65nm, 70nm, 5nm, 80nm, 85nm, 90nm, 95nm, 100nm and so on.
  • the shell can simultaneously enhance conductivity and stabilize the cathode material/electrolyte interface. If the thickness is too thick, too thick will cause additional unnecessary lithium ion migration paths, which will affect the electrical performance. A certain inhibitory effect.
  • the outer shell is composed of a layer of dense and uniform nano-microspheres, with smooth lithium ion diffusion and migration channels inside to improve ion conductivity and stabilize the structure of the surface of the positive electrode material particles.
  • the shell may only cover part of the outer surface of the base particles; or it may be covered on the entire outer surface of the base particles, that is, the shell wraps the base particles inside. In some embodiments, the shell covers the entire outer surface of the base particles.
  • the material forming the matrix particles is a lithium-rich manganese-based cathode material
  • the positive electrode material with the chemical composition has high ion conductivity and low electrolyte reaction activity,
  • the above-mentioned cathode material includes at least one of the following: 0.545Li 2 MnO 2.995 F 0.005 ⁇ 0.45Li 0.99 Ni 0.444 Co 0.444 Mn 0.122 O 1.995 F 0.005 ⁇ 0.005Li 1.3 Al 0.3 Ti 1.7 (PO 4 ) 3 , 0.545Li 2 Mn 0.989 Ti 0.011 O 2.995 F 0.005 ⁇ 0.45Li 0.976 Ni 0.444 Co 0.444 Mn 0.136 O 1.995 F 0.005 ⁇ 0.005Li 1.3 Al 0.3 Ti 1.7 (PO 4 ) 3 , and 0.545Li 2 Mn 0.989 Ti 0.011 O 2.995 F 0.005 ⁇ 0.45Li 0.976 Ni 0.444 Co 0.444 Mn 0.136 O 1.995 F 0.005 ⁇ 0.005Li 1.3 Al 0.3 Ti 1.7 (PO 4 ) 3 , and 0.545Li 2 Mn 0.989 Ti 0.011 O 2.9
  • the particle size distribution of the positive electrode material is 1-17 microns, in one embodiment, 4-15 microns, such as 4 microns, 5 microns, 6 microns, 7 microns, 8 microns, 9 microns, 10 microns. Micrometers, 11 micrometers, 12 micrometers, 13 micrometers, 14 micrometers, 15 micrometers, etc. Within this particle size distribution range, the positive electrode material has better performance. If it is not within the particle size distribution range, the processing performance of subsequent positive electrode pieces will be affected; and the diffusion distance of lithium ions inside the particles will be increased and the rate performance will be reduced.
  • the particle size distribution is the range of the particle size distribution of the positive electrode material.
  • the positive electrode material of the present disclosure can improve rate performance and cycle performance at the same time, and the above positive electrode material meets at least one of the following conditions: 0.1C rate discharge specific capacity is greater than or equal to 280mAh/g, in one embodiment, Is greater than or equal to 300mAh/g, such as 280mAh/g, 290mAh/g, 300mAh/g, 310mAh/g, 320mAh/g, 330mAh/g, 340mAh/g, 350mAh/g, 360mAh/g, 370mAh/g, 80mAh/ g, 390mAh/g, 400mAh/g, etc.; 1C rate discharge specific capacity is greater than or equal to 220mAh/g, in one embodiment it may be greater than or equal to 240mAh/g, such as 220mAh/g, 230mAh/g, 240mAh/g, 250mAh/ g, 260mAh/g, 270mAh/g, 280mAh/g, 290mAh/g, 300mAh/g, 310mAh/g, 320mAh/g,
  • a method for preparing the above-mentioned positive electrode material includes: ball milling a mixture of matrix particles and shell raw materials for 1-10 hours to obtain a mixed material, and mixing the above-mentioned mixed material at 300-900 It is calcined for 1-12 h under an atmosphere of O 2 /N 2 at °C to obtain a positive electrode material, wherein the shell raw material is nano lithium titanium phosphate, nano lithium germanium aluminum phosphate or nano lithium aluminum titanium phosphate.
  • This method can quickly and effectively obtain the above-mentioned positive electrode material, the steps are simple, the operation is easy, and the obtained positive electrode material has high ionic conductivity and low electrolyte reactivity, which can effectively improve the stability of the surface structure of the matrix particles while passing through the surface.
  • the modified matrix particles can significantly improve its rate and cycle performance.
  • the mixture of base particles and shell materials can be placed in a planetary ball mill for grinding and mixing, and the grinding time can be 1 hour, 2 hours, 3 hours, 4 hours, 5 hours, 6 hours, 7 hours, Hours, 9 hours, 10 hours, etc.
  • the mixed material obtained by ball milling can be placed at 300-900°C (for example, 300°C, 350°C, 400°C, 450°C, 500°C, 550°C, 600°C, 650°C, 700°C, 750°C, 800°C, 850°C, 900°C, etc.) calcining furnace is filled with O 2 /N 2 atmosphere (where the O 2 content is 0-100%, such as 0%, 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, 100%, etc.) calcination for 1 hour, 2 hours, 3 hours, 4 hours, 5 hours, 6 hours, 7 hours, hours, 9 Hours, 10 hours, 11 hours, 12 hours, etc.
  • O 2 /N 2 atmosphere where the O 2 content is 0-100%, such as 0%, 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, 100%, etc.
  • the ball mill can mix the base particles and the shell materials uniformly, so that the shell materials are evenly wrapped on the outer surface of the base particles, and calcination can make the base particles and the shell materials react with each other, so that the shell materials are tightly attached to the surface of the particles. . Furthermore, the above steps can coat the surface of the base particles with a nano-thickness shell, the operation is simple, the conditions are mild, and the performance of the obtained positive electrode material is better.
  • the base particles and the shell material can be 0.5% to 5% (mass ratio) (for example, 0.5%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%) of the base particles according to the shell material. %, 4%, 4.5%, 5%, etc.). Therefore, the coating effect is better. If the shell material is too small, the coating effect is not ideal, and the effect of improving the electrochemical performance is not good. Waste.
  • the positive electrode material obtained after calcination can be taken out and placed in a mortar/pestle for grinding.
  • a positive electrode material with a suitable particle size can be obtained, and the usability of the positive electrode material can be further improved.
  • the aforementioned matrix particles may be prepared by the following steps: the precursor material is heated at 300-800°C (for example, 300°C, 350°C, 400°C, 450°C, 500°C, 550°C, 600°C, 650°C °C, 700°C, 750°C, 800°C, etc.), O 2 /N 2 atmosphere (where the O 2 content is 0-100%, such as 0%, 10%, 20%, 30%, 40%, 50%, Calcined at 60%, 70%, 80%, 90%, 100%, etc.) for 4-12h (for example, 4h, 5h, 6h, 7h, 8h, 9h, 10h, 11h, 12h, etc.) to obtain the first calcined product.
  • 300-800°C for example, 300°C, 350°C, 400°C, 450°C, 500°C, 550°C, 600°C, 650°C °C, 700°C, 750°C, 800°C, etc.
  • the above-mentioned first calcined product is mixed with a lithium source, and the resulting mixture is heated at 600-950°C (for example, 600°C, 650°C, 700°C, 750°C, 800°C, 850°C, 900°C, 950°C, etc.), O 2 /N 2 atmosphere (where the O 2 content is 0-100%, such as 0%, 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, 100%, etc.
  • 600-950°C for example, 600°C, 650°C, 700°C, 750°C, 800°C, 850°C, 900°C, 950°C, etc.
  • O 2 /N 2 atmosphere where the O 2 content is 0-100%, such as 0%, 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, 100%, etc.
  • the precursor materials that can be used can include nickel cobalt manganese carbonate or nickel cobalt manganese hydroxide (for example, Ni 0.2 Co 0.2 Mn 0.6 CO 3 , Ni 0.3 Co 0.2 Mn 0.5 CO 3 , Ni 0.3 Co 0.2 Mn 0.5 ( OH) 2 , Ni 0.2 Co 0.1 Mn 0.7 CO 3 , Ni 0.2 Co 0.1 Mn 0.7 (OH) 2 ), the precursor material can be calcined at a temperature to change the form of carbonate or hydroxide into oxide form, the latter has The relatively well-developed pore channels facilitate the entry of lithium metal into the precursor in the subsequent calcination process, so that the lithium metal is uniformly distributed in the particle phase, and a uniform cathode material is formed.
  • nickel cobalt manganese carbonate or nickel cobalt manganese hydroxide for example, Ni 0.2 Co 0.2 Mn 0.6 CO 3 , Ni 0.3 Co 0.2 Mn 0.5 CO 3 , Ni 0.3 Co 0.2 Mn 0.5
  • the lithium source may include at least one of LiOH ⁇ H 2 O, Li 2 CO 3 and LiF.
  • the above-mentioned lithium source may be used in combination with NH 4 F, for example, NH 4 F may be matched with LiOH ⁇ H 2 O Or Li 2 CO 3 is used. After calcination, lithium can be introduced into the precursor material to effectively obtain matrix particles.
  • the mass ratio of the first calcined product to the lithium source may be 1.2 ⁇ 1.6:1, for example, 1.2:1, 1.3:1, 1.4:1, 1.5:1, 1.6:1, etc.
  • lithium can better enter the first calcined product and be evenly distributed in the particle phase to obtain a uniform positive electrode material.
  • the product after each calcination in the process of preparing the matrix particles, can be subjected to grinding treatment as required.
  • the mixture of the first calcined product and the lithium source can be fully ground with a mortar/pestle, and the mixture of the first calcined product and the lithium source can be fully ground in the mortar. .
  • the matrix particles can be prepared by the following steps: weighing a certain mass of precursor material, such as Ni 0.2 Co 0.2 Mn 0.6 CO 3 ; placing the precursor material in a 300-800 °C calciner, O 2 / Calcined in N 2 atmosphere (oxygen content 0-100%) for 4-12 hours; weigh a certain mass of lithium source, such as LiOH ⁇ H 2 O or Li 2 CO 3 , and LiF or NH 4 F; calcined the precursor and Mix the two lithium salts and grind the powder mixture thoroughly with a mortar/pestle; place the powder mixture in a 600-950°C calcining furnace and pass in an O 2 /N 2 atmosphere (containing 0-100% O 2 ) for calcination 10 -24h; Place the calcined powder material in a mortar and grind it sufficiently to obtain matrix particles.
  • precursor material such as Ni 0.2 Co 0.2 Mn 0.6 CO 3
  • LiF or NH 4 F lithium source
  • the above-mentioned matrix particles are prepared by the following steps: the precursor material is heated at 300-800°C (e.g., 300°C, 350°C, 400°C, 450°C, 500°C, 550°C, 600°C, 650°C , 700°C, 750°C, 800°C, etc.), O 2 /N 2 atmosphere (where the O 2 content is 0-100%, such as 0%, 10%, 20%, 30%, 40%, 50%, 60 %, 70%, 80%, 90%, 100%, etc.) and calcined for 4-12h (for example, 4h, 5h, 6h, 7h, 8h, 9h, 10h, 11h, 12h, etc.) to obtain the above-mentioned first calcined product.
  • 300-800°C e.g., 300°C, 350°C, 400°C, 450°C, 500°C, 550°C, 600°C, 650°C , 700°C, 750°C, 800°
  • the above-mentioned first calcined product is mixed with the above-mentioned lithium source, and the resulting mixture is heated at 600-950°C (for example, 600°C, 650°C, 700°C, 750°C, 800°C, 850°C, 900°C, 950°C, etc.), O 2 /N 2 atmosphere is calcined for 10-24h (for example, 10h, 11h, 12h, 13h, 14h, 15h, 16h, 17h, 18h, 19h, 20h, 1h, 22h, 23h, 24h, etc.) to obtain the second calcined product; After ball milling the mixture of the second calcined product and nano-TiO 2 for 2-8h (for example, 2h, 3h, 4h, 5h, 6h, 7h, 8h, etc.), the temperature is 750-850°C (for example, 750°C, 760°C, 770°C).
  • 600-950°C for example, 600°
  • O 2 /N 2 atmosphere (where the O 2 content is 0-100%, such as 0%, 10 %, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, 100%, etc.) at 4-16h (for example, 4h, 5h, 6h, 7h, 8h, 9h, 10h , 11h, 12h, 13h, 14h, 15h, 16h, etc.) to obtain the above-mentioned matrix particles.
  • the precursor, the lithium source, etc. may be consistent with the foregoing description, and will not be repeated here.
  • the nano-titanium oxide accounts for 0.1% to 1% (mass ratio) of the second calcined product, for example, it can be 0.1%, 0.2%, .3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, etc.;
  • the first additive accounts for 0.5% to 5% (mass ratio) of the third calcined product, for example, it can be 0.05%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, 5%, etc. Therefore, the coating effect of the outer shell is better, and the electrochemical performance of the obtained cathode material is better.
  • the surface of the base particles can be coated to form a shell in different ways.
  • the prepared shell material may be used to coat the matrix particles, so that the shell in the obtained positive electrode material is of the same substance, single crystal phase, and free of impurities.
  • the shell can be formed by the following steps: mixing the matrix particles with the shell material, and ball milling the resulting mixture for 1-10h (for example, 1h, 2h, 3h, 4h, 5h, 6h, 7h, 8h, 9h, After 10h, etc.), it is calcined at 300-900°C (such as 300°C, 400°C, 500°C, 600°C, 700°C, 800°C, 900°C, etc.), O 2 /N 2 atmosphere for 1-12h (such as 1h, 2h, 3h, 4h, 5h, 6h, 7h, 8h, 9h, 10h, 11h, 12h, etc.) to obtain the above cathode material, wherein the shell material is nano lithium titanium phosphate (LiTi 2 (PO 4 ) 3 ), phosphoric acid Lithium aluminum germanium (Li 1+ ⁇ " Al ⁇ Ge 2- ⁇ (PO 4 ) 3 ) or lithium aluminum titanium phosphate (Li 1+ ⁇ ” Al
  • the raw material forming the shell can be directly reacted with the matrix particles.
  • the shell material covers the matrix particles while reacting to form a shell with the target composition, but side reactions are likely to occur.
  • the shell contains The impurity phase affects the electrochemical performance of the obtained cathode material.
  • the shell can be formed by the following steps: mixing the above-mentioned matrix particles with additives, and ball milling the resulting mixture for 1-10h (for example, 1h, 2h, 3h, 4h, 5h, 6h, 7h, 8h, 9h, After 10h, etc.), at 300-1000°C (for example, 300°C, 400°C, 500°C, 600°C, 700°C, 800°C, 900°C, 1000°C, etc.), O 2 /N 2 atmosphere (where O 2 content It is 0-100%, such as 0%, 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, 100%, etc.) under calcination for 1-12h (e.g.
  • the additives include titanium-containing compounds and phosphorus-containing compound additives.
  • the second The additives include at least one of Li 2 CO 3 , TiO 2 , (NH 4 )H 2 PO 4 , Ti ⁇ OCH(CH 3 ) 2 ⁇ 4 , H 2 TiO 3 , (NH 4 ) 3 PO 4 and Li 3 PO 4
  • the above-mentioned second additive can be used in conjunction with Al(OH) 3.
  • the additive accounts for 0.5% to 5% (mass ratio) of the matrix particles. In an embodiment, it can be 0.5%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%. %, 4.5%, 5%, etc. Therefore, the coating effect of the outer shell is better, and the electrochemical performance of the obtained cathode material is better.
  • the ball milling in the step of forming the outer shell, can be performed by a planetary ball mill, the calcination can be performed in a calcining furnace, and the product obtained by each calcination can be ground with a mortar/pestle as required.
  • a shell can be formed on the outer surface of the matrix particles by the following steps: weigh a certain mass of nano-TiO 2 and the above-mentioned calcined material, grind and mix in a planetary ball mill for 2-8 hours, and then place it for about 750-850 °C calcining furnace, O 2 /N 2 atmosphere (oxygen content 0-100%) calcination 4-16h; weigh a certain mass of the first additive, nano-lithium titanium phosphate (LiTi 2 (PO 4 ) 3 ), lithium germanium aluminum phosphate (Li 1+ ⁇ ” Al ⁇ Ge 2- ⁇ (PO 4 ) 3 ) or lithium aluminum titanium phosphate (Li 1+ ⁇ ” Al ⁇ Ti 2- ⁇ (PO 4 ) 3 ), together with the above-mentioned calcined powder material Ball mill in a planetary ball mill for 1-10h until uniformly mixed; Place the ground powder material in a 300-900°C calciner, O 2 /N 2 atmosphere (containing 0
  • a shell can be formed on the outer surface of the matrix particles by the following steps: weigh a certain mass of a titanium-containing compound and a second additive of a phosphorus-containing compound, such as Li 2 CO 3 , Al(OH) 3 , TiO 2 , (NH 4 )H 2 PO 4 ; TiO 2 , Ti ⁇ OCH(CH 3 ) 2 ⁇ 4 , or H 2 TiO 3, etc., and Li 3 PO 4 , (NH 4 ) 3 PO 4 , or Li 3 PO 4 Etc.; mix the matrix particles with the above-mentioned second additive, and ball mill in a planetary ball mill for 1-10h until uniformly mixed; put the mixed material in a 300-1000°C calciner, O 2 /N 2 atmosphere (containing 0- 100% O 2 ) calcination for 1-12 h; after calcination, the product is taken out and placed in a mortar/pestle for grinding to obtain a positive electrode material.
  • a phosphorus-containing compound such as Li 2 CO
  • a lithium ion battery in an embodiment of the present disclosure, includes the aforementioned positive electrode material.
  • the rate performance and cycle performance of the lithium ion battery are better, and the energy density is higher.
  • the lithium ion battery can also include the necessary structures and components of a conventional lithium ion battery, for example, it can include a positive electrode sheet, a negative electrode sheet, an electrolyte, a separator, and a casing.
  • a conventional lithium ion battery can include a positive electrode sheet, a negative electrode sheet, an electrolyte, a separator, and a casing.
  • the structures of conventional lithium-ion batteries are assembled together, in which the positive electrode material described above constitutes the positive electrode active material in the positive electrode sheet.
  • an electric vehicle in an embodiment of the present disclosure, includes the above-mentioned lithium ion battery.
  • the electric vehicle using the above-mentioned lithium-ion battery has better endurance.
  • the electric vehicle may also include the necessary structures and components of a conventional electric vehicle, such as an engine, a body, a tire, a bearing, an interior trim, etc., which can be carried out with reference to related technologies. I will not repeat them one by one.
  • the particle size distribution of the cathode material particles is 4-15 ⁇ m, and the thickness of the shell layer is 100 nm.
  • the particle size distribution of the cathode material particles is 4-15 ⁇ m, and the thickness of the shell layer is 100 nm.
  • the particle size distribution of the cathode material particles is 4-15 ⁇ m, and the thickness of the shell layer is 450 nm.
  • the particle size distribution of the cathode material particles is 4-15 ⁇ m, and the thickness of the shell layer is 200 nm.
  • the particle size distribution of the cathode material particles is 4-15 ⁇ m, and the thickness of the shell layer is 550 nm.
  • the particle size distribution of the cathode material particles is 4-15 ⁇ m, and the thickness of the shell layer is 550 nm.
  • the particle size distribution of the cathode material particles is 4-15 ⁇ m, and the thickness of the shell layer is 550 nm.
  • the particle size distribution of the cathode material particles is 1-17 ⁇ m.
  • the positive pole piece is composed of 92wt% active material (that is, the positive electrode material prepared above), 4wt% Super-P conductive agent and 4wt% PVDF binder.
  • the electrolyte is prepared by 1M LiPF 6 , the same volume of ethylene carbonate and dimethyl carbonate, and corresponding additives.
  • the test system for the first charge and discharge is that the voltage window is 2-4.8V, the charge-discharge rate is 0.1C; the rate performance is tested at the discharge rates of 0.1C, 0.2C, 0.5C, 1C and 2C, and the voltage window is 2-4.6 V.
  • FIG. 1 shows the first charge and discharge curves of the positive electrode material in the comparative example and the example 1.
  • FIG. 1 shows the first charge and discharge curves of the positive electrode material in the comparative example and the example 1.
  • FIG. 2 shows the first charge and discharge curves of the positive electrode material in Comparative Example and Example 2.
  • FIG. 3 shows the first charge and discharge curves of the positive electrode material in Comparative Example and Example 3.
  • FIG. 4 shows the rate performance test results of the positive electrode materials in Comparative Example and Example 1.
  • FIG. 5 shows the rate performance test results of the positive electrode materials in Comparative Example and Example 2.
  • FIG. 6 shows the rate performance test results of the positive electrode materials in Comparative Example and Example 3.
  • FIG. 7 shows the cycle performance test results of the positive electrode material in Comparative Example and Example 1.
  • FIG. 8 shows the cycle performance test results of the positive electrode material in Comparative Example and Example 2.
  • FIG. 9 shows the cycle performance test results of the positive electrode material in Comparative Example and Example 3.
  • the first charge specific capacity corresponding to Examples 1-3 is between 340-360 mAh/g, and the discharge specific capacity is between 300-330 mAh/g.
  • the cathode material of the embodiment of the present disclosure can increase the specific discharge capacity of the lithium-rich manganese-based cathode material by 4.5%.
  • the first charge specific capacity and discharge specific capacity of the lithium-rich manganese-based cathode material in the comparative example were 346.9mAh/g and 308.7mAh/g, respectively, and the first coulombic efficiency was 88.98%; the first charge ratio of the cathode material in Example 2
  • the capacity and discharge specific capacity are 382.8mAh/g and 341mAh/g, respectively, and the first coulombic efficiency is 89.10%.
  • the cathode material of the embodiment of the present disclosure can greatly improve the discharge specific capacity by about 10.5%.
  • the first specific charging capacity and the specific discharge specific capacity corresponding to Example 3 are 348.6 mAh/g and 300.8 mAh/g, respectively, and the first coulombic efficiency is 86.3%. Compared with the comparative example, the discharge specific capacity and coulombic efficiency are reduced.
  • the positive electrode material prepared in Example 2 has a capacity retention rate of 86.4% after 50 charge/discharge cycles. Compared with the comparative example, its cycle capacity retention rate is increased by 6.0%.
  • the first charge specific capacity and discharge specific capacity of the product of Example 4 were 315mAh/g, and the specific discharge capacity at 1C rate was 236mAh/g; after 50 charge/discharge cycles, the capacity retention rate was 85.4%.
  • the first charge specific capacity and discharge specific capacity of the product of Example 5 were respectively 311 mAh/g, and the specific discharge capacity at 1C rate was 232 mAh/g; after 50 charge/discharge cycles, the capacity retention rate was 85.9%.
  • the first charge specific capacity and discharge specific capacity of the product of Example 6 were respectively 151 mAh/g, and the specific discharge capacity at 1C rate was 144 mAh/g; after 50 charge/discharge cycles, the capacity retention rate was 99.1%.
  • the positive electrode matrix material of this embodiment is lithium iron phosphate, which has a very low gram capacity, and its cycle stability is very high.
  • the first specific charge capacity and specific discharge capacity of the product of Example 7 were 209 mAh/g, and the specific discharge capacity at 1C rate was 189 mAh/g; after 50 charge/discharge cycles, the capacity retention rate was 89.6%.
  • This embodiment is a high nickel ternary material, the discharge gram capacity is between the rich manganese-based cathode material and the lithium iron phosphate cathode material, and the cycle capacity retention rate is also the same.

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Abstract

一种正极材料及其制备方法、锂离子电池和电动汽车，该正极材料包括：基体颗粒，形成所述基体颗粒的材料包括富锂锰基材料、镍钴锰酸锂、镍钴铝酸锂、磷酸铁锂、锰酸锂、镍钴锰铝酸锂和镍锰酸锂中的至少一种；及外壳，所述外壳包覆在所述基体颗粒的至少一部分外表面上。

Description

正极材料及其制备方法、锂离子电池和电动汽车 技术领域
本公开涉及锂离子电池技术领域，例如涉及正极材料及其制备方法和锂离子电池和电动汽车。
背景技术
目前，在各国政府的政策导引下，整个汽车行业正在掀起一场电动化与清洁化浪潮，然而与燃油车相比，电动汽车仍然存在诸多问题，例如电池安全问题、续航里程问题、充电耗时较长问题等。因此，当前的电池技术仍不能完全满足消费者的使用需求，获得更高能量密度的锂离子电池是亟待解决的问题。
富锂锰基正极材料xLi 2MnO 3·(1-x)LiMO 2(M＝Ni，Co，Mn等)具有≥250mAh/g的比容量、高达240℃的DSC分解温度以及相对较低的成本，是高能量密度正极材料的重要开发方向之一。然而富锂锰基材料也存在诸多问题，例如倍率性能差且循环容量保持率较低，且材料中锰元素含量达到50％以上，锰金属元素具有很差的金属电导率，降低了材料本征的离子电导率，从而使得材料不能在大电流充放电时快速嵌入、嵌出锂离子。为解决这些问题，研究者们进行了大量的工作，但是目前的改进措施所能取得的改善效果有限，仅能单方面地提高倍率或者循环性能。
因而，目前正极材料相关技术仍有待改进。
发明内容
以下是对本文详细描述的主题的概述。本概述并非是为了限制权利要求的保护范围。
本公开提供一种正极材料及其制备方法、锂离子电池和电动汽车。
本公开在一实施例中提供一种正极材料，所述正极材料包括：基体颗粒，形成所述基体颗粒的材料包括富锂锰基材料、镍钴锰酸锂、镍钴铝酸锂、磷酸 铁锂、锰酸锂、镍钴锰铝酸锂和镍锰酸锂中的至少一种；及外壳，所述外壳包覆在所述基体颗粒的至少一部分外表面上，形成所述外壳的材料包括磷酸钛锂、磷酸锗铝锂和磷酸钛铝锂中的至少一种。
本公开的正极材料中，磷酸钛锂、磷酸锗铝锂或磷酸钛铝锂包覆基体颗粒，也即对基体颗粒进行了表面修饰，所得正极材料具有高导离子性、低电解液反应活性，能够有效提高基体颗粒的表层结构稳定性，显著改善了其倍率和循环性能。
在一实施例中，所述外壳的厚度为0～500nm且不为0。
在一实施例中，所述外壳的厚度为0～200nm且不为0。
在一实施例中，所述外壳的厚度为0～100nm且不为0。
在一实施例中，所述正极材料的粒径分布为1～17微米，在一实施例中为4～15微米。所述粒径分布为正极材料的粒径分布范围。
在一实施例中，形成基体颗粒的材料为所述富锂锰基材料，所述正极材料的化学组成为：
aLi 2+αMn 1-μTi μO 3-νF ν·bLi 1+α'MO 2-ν'F ν'·cLi 1+α”Al βM' 2-β(PO 4) 3，
其中，a+b+c＝1，0<a<0.6，0<b<0.5，0<c≤0.05，0≤α≤0.04，0<μ≤0.5，0.005≤ν≤0.02，0≤α'≤0.04，-0.02≤α”<1，0.005≤ν'≤0.02，0≤β<0.5，
M为Ni、Co、Mn、Al、Mg、Ti、Zr、Zn、Ca、B、Ce和Cr等中的至少一种元素，
M'为Ti、Ge中的至少一种元素。
在一实施例中，所述正极材料包括以下的至少一种：
0.545Li 2MnO 2.995F 0.005·0.45Li 0.99Ni 0.444Co 0.444Mn 0.122O 1.995F 0.005·0.005Li 1.3Al 0.3Ti 1.7(PO 4) 3，
0.545Li 2Mn 0.989Ti 0.011O 2.995F 0.005·0.45Li 0.976Ni 0.444Co 0.444Mn 0.136O 1.995F 0.005·0.005Li 1.3Al 0.3Ti 1.7(PO 4) 3，和
0.545Li 2Mn 0.989Ti 0.011O 2.995F 0.005·0.45Li 0.976Ni 0.444Co 0.444Mn 0.136O 1.995F 0.005·0.005Li 1.3Al 0.3Ti 1.7(PO 4) 3。
在一实施例中，所述正极材料满足以下条件的至少之一：
0.1C倍率放电比容量大于等于280mAh/g，一实施例中为大于等于300mAh/g；
1C倍率放电比容量大于等于220mAh/g，一实施例中为大于等于240mAh/g；
50周充放电循环后容量保持率大于等于85％，一实施例中大于等于86％。
本公开在一实施例中提供一种制备前面所述的正极材料的方法，所述方法包括：将基体颗粒和外壳原料的混合物球磨1-10小时，得到混合材料，将所述混合材料于300–900℃、O 2/N 2气氛下煅烧1–12h，得到正极材料，其中，所述外壳原料为纳米磷酸钛锂、纳米磷酸锗铝锂或者纳米磷酸钛铝锂。该方法可以快速有效地获得前面所述的正极材料，步骤简单，操作容易，且得到的正极材料具有高导离子性、低电解液反应活性，能够有效提高基体颗粒的表层结构稳定性，同时经过表面修饰的基体颗粒可以显著改善其倍率和循环性能。
在一实施例中，所述基体颗粒是通过以下步骤制备的：将前驱体材料于300–800℃、O 2/N 2气氛下煅烧4–12h，得到第一煅烧产物，将所述第一煅烧产物与锂源混合，并将得到的混合物于600–950℃、O 2/N 2气氛下煅烧10–24h，得到所述基体颗粒。
在一实施例中，所述基体颗粒是通过以下步骤制备的：将前驱体材料于300–800℃、O 2/N 2气氛下煅烧4–12h，得到所述第一煅烧产物，将所述第一煅烧产物与所述锂源混合，并将得到的混合物于600–950℃、O 2/N 2气氛下煅烧10–24h，得到第二煅烧产物；将所述第二煅烧产物与纳米TiO 2的混合物球磨2–8h后，于750–850℃、O 2/N 2气氛下煅烧4–16h，得到所述基体颗粒。
本公开在一实施例中提供了一种锂离子电池，该锂离子电池包括前面所述的正极材料。该锂离子电池的倍率性能和循环性能均较佳，能量密度较高。
本公开在一实施例中提供了一种电动汽车，该电动汽车包括前面所述的锂离子电池。采用上述锂离子电池的该电动汽车，续航能力较好。
附图说明
附图用来提供对本公开技术方案的进一步理解，并且构成说明书的一部分，与本申请的实施例一起用于解释本公开的技术方案，并不构成对本公开技术方 案的限制。
图1是本公开对比例和实施例1中的正极材料的首次充放电曲线。
图2是本公开对比例和实施例2中的正极材料的首次充放电曲线。
图3是本公开对比例和实施例3中的正极材料的首次充放电曲线。
图4是本公开对比例和实施例1中的正极材料的倍率性能测试结果。
图5是本公开对比例和实施例2中的正极材料的倍率性能测试结果。
图6是本公开对比例和实施例3中的正极材料的倍率性能测试结果。
图7是本公开对比例和实施例1中的正极材料的循环性能测试结果。
图8是本公开对比例和实施例2中的正极材料的循环性能测试结果。
图9是本公开对比例和实施例3中的正极材料的循环性能测试结果。
具体实施例
下面结合附图并通过具体实施方式来进一步说明本公开的技术方案。
本公开在一实施例中提供了一种正极材料，上述正极材料包括：基体颗粒，形成上述基体颗粒的材料包括富锂锰基材料、镍钴锰酸锂、镍钴铝酸锂、磷酸铁锂、锰酸锂、镍钴锰铝酸锂和镍锰酸锂中的至少一种；及外壳，上述外壳包覆在上述基体颗粒的至少一部分外表面上，形成上述外壳的材料包括磷酸钛锂、磷酸锗铝锂和磷酸钛铝锂中的至少一种。该磷酸钛锂(LiTi 2(PO 4) 3，LTP)、磷酸锗铝锂(Li 1+α”Al βGe 2-β(PO 4) 3)或磷酸钛铝锂(Li 1+α”Al βTi 2-β(PO 4) 3)表面修饰或包覆活性材料得到的正极材料，具有高导离子性、低电解液反应活性，能够有效提高基体颗粒的表层结构稳定性，同时经过表面修饰的基体颗粒可以显著改善其倍率和循环性能。
在一实施例中，形成基体颗粒的材料为富锂锰基材料(或称为富锂锰基正极材料)。富锂锰基正极材料xLi 2MnO 3·(1-x)LiMO 2(M＝Ni，Co，Mn等)被认为是由Li 2MnO 3(C2/m空间群)和LiMO 2(R-3m空间群)构成，因此富锂锰基正极材料具有复杂的两相晶体结构。在材料合成过程中，控制两种晶相的相对含量很大程度上决定着该正极材料比容量的高低。此外，即使获得高比容量的富锂锰基正极材料，但是经过长时间的充放电循环后，容量保持率会迅速衰 减。容量保持率衰减的一种可能的机理为：富锂锰基正极材料晶体结构中过渡金属层八面体位点上的过渡金属离子通过中间位置的四面体位点迁移到锂层的八面体位点上；过渡金属离子几乎可以在过渡金属层八面体位点与中间位置的四面体位点之间进行可逆穿梭(100％SOC条件下，其含量达到约4％)；到达锂层的四面体位点后，过渡金属离子则基本上只可以单向迁移到锂层的八面体位点上，这种锂/过渡金属离子混排可能是造成该材料循环稳定差的重要原因。也有观点认为在充放电循环过程中，LiMn 2O 4晶相的产生是导致容量衰减的重要因素。因此，富锂锰基正极材料存在着固有的缺陷，导致其表现出严重的循环容量保持率的问题。然而，本公开提供的经过包覆的富锂锰基正极材料，包覆外壳能够很好地与基体颗粒结构契合、可以提供良好的锂离子迁移通道，并能够提高基体颗粒的电化学结构稳定性，既可以在改善循环稳定性的同时提高材料的离子导电率，克服了现有改性富锂锰基正极材料只能单方面地提高倍率性能或者循环性能的问题。
在一实施例中，采用的富锂锰基正极材料可以包括镍钴锰碳酸盐或者镍钴锰氢氧化物，在一实施例中可以为Ni 0.2Co 0.2Mn 0.6CO 3、Ni 0.3Co 0.2Mn 0.5CO 3、Ni 0.3Co 0.2Mn 0.5(OH) 2、Ni 0.2Co 0.1Mn 0.7CO 3、Ni 0.2Co 0.1Mn 0.7(OH) 2等。
在一实施例中，形成上述外壳的材料包括磷酸钛锂、磷酸锗铝锂和磷酸钛铝锂中的至少一种。本公开中，外壳材料具有较高的离子导电性可以有效改善锂离子在界面处的迁移速率；另外外壳材料与电解液之间的反应活性较低，可以显著降低电解液对正极材料的侵蚀，增强循环过程中正极材料颗粒的结构稳定性。此外，上述外壳材料还能够起到缓冲层(buffer layer)的作用，具有双功能，能够更好地提高正极材料的电化学性能。
在一实施例中，上述外壳的厚度可以为0～500nm且不为0，在一实施例中可以为0～200nm且不为0，在一实施例中可以为0～100nm且不为0，例如5nm、10nm、15nm、20nm、25nm、30nm、35nm、40nm、45nm、50nm、55nm、60nm、65nm、70nm、5nm、80nm、85nm、90nm、95nm、100nm等等。在该厚度范围内，该外壳可以同时起到增强导电性和稳定正极材料/电解液界面的作用，如果厚度过厚，则太厚导致增加额外非必要的锂离子迁移路径，对电性能发挥产生一定的抑制作用。
在一实施例中，外壳由一层致密均匀的纳米微球构成，内部具有顺畅的锂离子扩散迁移通道以提高离子导电率、稳定正极材料颗粒表面的结构。
在一实施例中，外壳可以仅包覆在基体颗粒的部分外表面上；也可以包覆在基体颗粒的全部外表面上，即外壳将基体颗粒包裹在其内部。一些实施例中，外壳包覆在基体颗粒的全部外表面上。由此，得到的正极材料的离子导电率较高，同时循环性能和倍率性能更佳。
在一实施例中，形成基体颗粒的材料为富锂锰基正极材料，上述正极材料的化学组成为：aLi 2+αMn 1-μTi μO 3-νF ν·bLi 1+α'MO 2-ν'F ν'·cLi 1+α”Al βM' 2-β(PO 4) 3，其中，a+b+c＝1，0<a<0.6，0<b<0.5，0<c≤0.05，0≤α≤0.04，0<μ≤0.5，0.005≤ν≤0.02，0≤α'≤0.04，-0.02≤α”<1，0.005≤ν'≤0.02，0≤β<0.5，M为Ni、Co、Mn、Al、Mg、Ti、Zr、Zn、Ca、B、Ce和Cr等中的至少一种元素，M'为Ti、Ge中的至少一种元素。具有该化学组成的正极材料，具有高导离子性、低电解液反应活性，能够有效提高富锂锰基基体颗粒表层结构稳定性，同时可以显著改善其倍率性能和循环性能。
在一实施例中，上述正极材料包括以下的至少一种：0.545Li 2MnO 2.995F 0.005·0.45Li 0.99Ni 0.444Co 0.444Mn 0.122O 1.995F 0.005·0.005Li 1.3Al 0.3Ti 1.7(PO 4) 3，0.545Li 2Mn 0.989Ti 0.011O 2.995F 0.005·0.45Li 0.976Ni 0.444Co 0.444Mn 0.136O 1.995F 0.005·0.005Li 1.3Al 0.3Ti 1.7(PO 4) 3，和0.545Li 2Mn 0.989Ti 0.011O 2.995F 0.005·0.45Li 0.976Ni 0.444Co 0.444Mn 0.136O 1.995F 0.005·0.005Li 1.3Al 0.3Ti 1.7(PO 4) 3。
在一实施例中，上述正极材料的粒径分布为1～17微米，在一实施例中为4～15微米，例如4微米、5微米、6微米、7微米、8微米、9微米、10微米、11微米、12微米、13微米、14微米、15微米等。在该粒径分布范围内，正极材料性能较佳，如果不在该粒径分布范围内，则会影响后续正极极片的加工性能；以及增加锂离子在颗粒内部的扩散距离，降低倍率性能。所述粒径分布为正极材料的粒径分布范围。
在一实施例中，本公开的正极材料可以同时改善倍率性能和循环性能，且上述正极材料满足以下条件的至少之一：0.1C倍率放电比容量大于等于 280mAh/g，在一实施例中可以为大于等于300mAh/g，例如280mAh/g、290mAh/g、300mAh/g、310mAh/g、320mAh/g、330mAh/g、340mAh/g、350mAh/g、360mAh/g、370mAh/g、80mAh/g、390mAh/g、400mAh/g等；1C倍率放电比容量大于等于220mAh/g，在一实施例中可以为大于等于240mAh/g，例如220mAh/g、230mAh/g、240mAh/g、250mAh/g、260mAh/g、270mAh/g、280mAh/g、290mAh/g、300mAh/g、310mAh/g、320mAh/g、330mAh/g、340mAh/g、350mAh/g等；50周充放电循环后容量保持率大于等于85％，在一实施例中可以为大于等于86％，例如85％、85.5％、86％、86.5％、87％、87.5％、88％、88.5％、89％、89.5％、90％等。
本公开在一实施例中提供了一种制备前面上述的正极材料的方法，该方法包括：将基体颗粒和外壳原料的混合物球磨1-10小时，得到混合材料，将上述混合材料于300–900℃、O 2/N 2气氛下煅烧1–12h，得到正极材料，其中，上述外壳原料为纳米磷酸钛锂、纳米磷酸锗铝锂或者纳米磷酸钛铝锂。该方法可以快速有效地获得前面上述的正极材料，步骤简单，操作容易，且得到的正极材料具有高导离子性、低电解液反应活性，能够有效提高基体颗粒的表层结构稳定性，同时经过表面修饰的基体颗粒可以显著改善其倍率和循环性能。
在一实施例中，可以将基体颗粒和外壳原料的混合物置于行星式球磨机中进行研磨混合，研磨时间可以为1小时、2小时、3小时、4小时、5小时、6小时、7小时、小时、9小时、10小时等，接着，可以将球磨得到的混合材料置于300–900℃(例如300℃、350℃、400℃、450℃、500℃、550℃、600℃、650℃、700℃、750℃、800℃、850℃、900℃等)煅烧炉中，通入O 2/N 2气氛(其中，O 2含量为0–100％，例如0％、10％、20％、30％、40％、50％、60％、70％、80％、90％、100％等)煅烧1小时、2小时、3小时、4小时、5小时、6小时、7小时、小时、9小时、10小时、11小时、12小时等。由此，球磨可以将基体颗粒和外壳原料混合均匀，使得外壳原料均匀包裹在基体颗粒外表面，而煅烧则可以使得基体颗粒和外壳原料相互反应，使外壳材料在颗粒表面两者贴合紧固。进而，上述步骤可以在基体颗粒表面包覆纳米级厚度的外壳，操作简单，条件温和，得到的正极材料性能较佳。
在一实施例中，可以将基体颗粒和外壳原料按照外壳原料占基体颗粒的 0.5％～5％(质量比)(例如0.5％、1％、1.5％、2％、2.5％、3％、3.5％、4％、4.5％、5％等)的比例混合。由此，包覆效果较佳，如果外壳原料过少，则包覆效果不理想，改善电化学性能的效果不佳，如果过多，则包覆层过厚影响锂离子传导，且造成材料的浪费。
在一实施例中，根据实际需要，煅烧结束后得到的正极材料可以取出并置于研钵/杵进行研磨。由此，可以获得粒径合适的正极材料，进一步提高正极材料的使用性能。
在一实施例中，上述基体颗粒可以是通过以下步骤制备的：将前驱体材料于300–800℃(例如300℃、350℃、400℃、450℃、500℃、550℃、600℃、650℃、700℃、750℃、800℃等)、O 2/N 2气氛(其中，O 2含量为0–100％，例如0％、10％、20％、30％、40％、50％、60％、70％、80％、90％、100％等)下煅烧4–12h(例如4h、5h、6h、7h、8h、9h、10h、11h、12h等)，得到第一煅烧产物，将上述第一煅烧产物与锂源混合，并将得到的混合物于600–950℃(例如600℃、650℃、700℃、750℃、800℃、850℃、900℃、950℃等)、O 2/N 2气氛(其中，O 2含量为0–100％，例如0％、10％、20％、30％、40％、50％、60％、70％、80％、90％、100％等)下煅烧10–24h(例如10h、11h、12h、13h、14h、15h、16h、17h、18h、19h、20h、21h、22h、23h、24h等)，得到上述基体颗粒。其中，可以采用的前驱体材料可以包括镍钴锰碳酸盐或镍钴锰氢氧化物(例如Ni 0.2Co 0.2Mn 0.6CO 3、Ni 0.3Co 0.2Mn 0.5CO 3、Ni 0.3Co 0.2Mn 0.5(OH) 2、Ni 0.2Co 0.1Mn 0.7CO 3、Ni 0.2Co 0.1Mn 0.7(OH) 2)，前驱体材料经过煅烧温度可以让碳酸盐或氢氧化物形式变成氧化物形式，后者具有相对发达的孔隙孔道，有利于后续煅烧工序中锂金属进入到前驱体，使锂金属在颗粒体相分布均匀，形成均一的正极材料。锂源可以包括LiOH·H 2O、Li 2CO 3和LiF中的至少一种，任选地，可以将上述锂源与NH 4F配合使用，例如NH 4F配可以配合LiOH·H 2O或Li 2CO 3使用。煅烧后，可以向前驱体材料中引入锂，有效得到基体颗粒。
在一实施例中，第一煅烧产物与锂源的质量比例可以为1.2～1.6：1，例如1.2:1、1.3:1、1.4:1、1.5:1、1.6:1等。由此，锂可以更好地进入第一煅烧产物中，并在颗粒体相中分布均匀，得到均一的正极材料。
本公开中，在制备基体颗粒的过程中，每次煅烧后的产物均可以根据需要 进行研磨处理。
在一实施例中，可以将第一煅烧产物和锂源的混合物用研钵/杵对粉末混合物进行充分研磨，并将经过煅烧的第一煅烧产物和锂源的混合物置于研钵中充分研磨。
在一实施例中，可以通过以下步骤制备基体颗粒：称量一定质量的前驱体材料，如Ni 0.2Co 0.2Mn 0.6CO 3；将前驱体材料置于300–800℃煅烧炉中、O 2/N 2气氛(氧含量0–100％)煅烧4–12h；称量一定质量的锂源，例如LiOH·H 2O或Li 2CO 3、以及LiF或NH 4F；将煅烧后的前驱体以及两种锂盐混合并用研钵/杵对粉末混合物进行充分研磨；将粉末混合物置于600–950℃煅烧炉、并通入O 2/N 2气氛(含0–100％的O 2)煅烧10–24h；将煅烧后的粉末材料置于研钵中充分研磨，得到基体颗粒。
在一实施例中，上述基体颗粒是通过以下步骤制备的：将前驱体材料于300–800℃(例如300℃、350℃、400℃、450℃、500℃、550℃、600℃、650℃、700℃、750℃、800℃等)、O 2/N 2气氛(其中，O 2含量为0–100％，例如0％、10％、20％、30％、40％、50％、60％、70％、80％、90％、100％等)下煅烧4–12h(例如4h、5h、6h、7h、8h、9h、10h、11h、12h等)，得到上述第一煅烧产物，将上述第一煅烧产物与上述锂源混合，并将得到的混合物于600–950℃(例如600℃、650℃、700℃、750℃、800℃、850℃、900℃、950℃等)、O 2/N 2气氛下煅烧10–24h(例如10h、11h、12h、13h、14h、15h、16h、17h、18h、19h、20h、1h、22h、23h、24h等)，得到第二煅烧产物；将上述第二煅烧产物与纳米TiO 2的混合物球磨2–8h后(例如2h、3h、4h、5h、6h、7h、8h等)，于750–850℃(例如750℃、760℃、770℃、780℃、790℃、800℃、810℃、820℃、830℃、840℃、850℃等)、O 2/N 2气氛(其中，O 2含量为0–100％，例如0％、10％、20％、30％、40％、50％、60％、70％、80％、90％、100％等)下煅烧4–16h(例如4h、5h、6h、7h、8h、9h、10h、11h、12h、13h、14h、15h、16h等)，得到上述基体颗粒。其中，前驱体、锂源等均可以与前文描述一致，在此不再一赘述。
在一实施例中，纳米氧化钛占第二煅烧产物的0.1％～1％(质量比)，例如可以为0.1％、0.2％、.3％、0.4％、0.5％、0.6％、0.7％、0.8％、0.9％、1％等；第 一添加剂占第三煅烧产物的0.5％～5％(质量比)，例如可以为0.05％、1％、1.5％、2％、2.5％、3％、3.5％、4％、4.5％、5％等。由此，外壳的包覆效果更好，得到的正极材料的电化学性能更佳。
在一实施例中，可以采用不同的方式在基体颗粒的表面包覆形成外壳。一种实施方式中，可以制备好的外壳原料对基体颗粒进行包覆，由此，得到的正极材料中的外壳是同一种物质、晶相单一、无杂质。
在一实施例中，可以通过以下步骤形成外壳：将基体颗粒与外壳原料混合，并将得到的混合物球磨1-10h(例如1h、2h、3h、4h、5h、6h、7h、8h、9h、10h等)后，于300–900℃(例如300℃、400℃、500℃、600℃、700℃、800℃、900℃等)、O 2/N 2气氛下煅烧1–12h(例如1h、2h、3h、4h、5h、6h、7h、8h、9h、10h、11h、12h等)，得到上述正极材料，其中，上述外壳原料为纳米磷酸钛锂(LiTi 2(PO 4) 3)、磷酸锗铝锂(Li 1+α”Al βGe 2-β(PO 4) 3)或者磷酸钛铝锂(Li 1+α”Al βTi 2-β(PO 4) 3)。
在另一实施例中，可以将形成外壳的原料直接与基体颗粒进行反应，反应过程中，外壳原料包覆基体颗粒的同时，反应生成具有目标成分的外壳，但是容易产生副反应，外壳中含有杂相而影响得到的正极材料的电化学性能。
在一实施例中，可以通过以下步骤形成外壳：将上述基体颗粒与添加剂混合，并将得到的混合物球磨1–10h(例如1h、2h、3h、4h、5h、6h、7h、8h、9h、10h等)后，于300–1000℃(例如300℃、400℃、500℃、600℃、700℃、800℃、900℃、1000℃等)、O 2/N 2气氛(其中，O 2含量为0–100％，例如0％、10％、20％、30％、40％、50％、60％、70％、80％、90％、100％等)下煅烧1–12h(例如1h、2h、3h、4h、5h、6h、7h、8h、9h、10h、11h、12h等)，得到上述正极材料，其中，添加剂包括含钛化合物和含磷化合物添加剂，在一实施例中，第二添加剂包括Li 2CO 3、TiO 2、(NH 4)H 2PO 4、Ti{OCH(CH 3) 2} 4、H 2TiO 3、(NH 4) 3PO 4和Li 3PO 4中的至少一种，任选地，上述第二添加剂可以和Al(OH) 3配合使用。
在一实施例中，添加剂占基体颗粒的0.5％～5％(质量比)，在一实施例中可以为0.5％、1％、1.5％、2％、2.5％、3％、3.5％、4％、4.5％、5％等。由此，外壳的包覆效果更好，得到的正极材料的电化学性能更佳。
在一实施例中，上述形成外壳的步骤中，球磨可以采用行星式球磨机进行，煅烧可以在煅烧炉中进行，而每次煅烧得到的产物均可以根据需要采用研钵/杵进行研磨。
在一实施例中，可以通过以下步骤在基体颗粒外表面形成外壳：称取一定质量的纳米TiO 2与上述煅烧后的物料置于行星式球磨机研磨混合2–8h，随后置于约750–850℃煅烧炉、O 2/N 2气氛(氧含量0–100％)煅烧4–16h；称取一定质量的第一添加剂，纳米磷酸钛锂(LiTi 2(PO 4) 3)、磷酸锗铝锂(Li 1+α”Al βGe 2-β(PO 4) 3)或者磷酸钛铝锂(Li 1+α”Al βTi 2-β(PO 4) 3)，与上述煅烧后的粉末材料一起置于行星式球磨机中球磨1–10h至均匀混合；将研磨后的粉末材料置于300–900℃煅烧炉、O 2/N 2气氛(含0–100％的O 2)煅烧1–12h；煅烧结束后取出并置于研钵/杵进行研磨，得到正极材料。
在另一实施例中，可以通过以下步骤在基体颗粒外表面形成外壳：称量一定质量的含钛化合物和含磷化合物的第二添加剂，例如Li 2CO 3、Al(OH) 3、TiO 2、(NH 4)H 2PO 4；TiO 2、Ti{OCH(CH 3) 2} 4、或者H 2TiO 3等，以及Li 3PO 4、(NH 4) 3PO 4、或者Li 3PO 4等；将基体颗粒与上述第二添加剂混合，并在行星式球磨机中球磨1–10h至均匀混合；将混合后的物料置于300–1000℃煅烧炉、O 2/N 2气氛(含0–100％的O 2)煅烧1–12h；煅烧结束后取出产物并置于研钵/杵进行研磨，得到正极材料。
本公开在一实施例中提供了一种锂离子电池。该锂离子电池包括前面上述的正极材料。该锂离子电池的倍率性能和循环性能均较佳，能量密度较高。
可以理解，除了前面描述的正极材料，该锂离子电池还可以包括常规锂离子电池必要的结构和部件，例如可以包括正极片、负极片、电解液、隔离膜和外壳等，上述各部件可以按照常规锂离子电池的结构组装在一起，其中，前面描述的正极材料构成正极片中的正极活性材料。
本公开在一实施例中提供了一种电动汽车，该电动汽车包括上述的锂离子电池。采用上述锂离子电池的该电动汽车，续航能力较好。
可以理解，除了前面描述的锂离子电池，该电动汽车还可以包括常规电动汽车必要的结构和部件，例如发动机、车身、轮胎、轴承、内饰等等，具体均 可参照相关技术进行，在此不再一一赘述。
下面详细描述本公开的实施例。
实施例1
将1mol的Ni 0.2Co 0.2Mn 0.6CO 3置于约700℃煅烧炉、氧含量2％的O 2/N 2气氛中煅烧约8h，然后与1.535mol的LiOH·H 2O和0.00495mol的NH 4F置于研磨中充分研磨混合，随后置于约820℃煅烧炉、氧含量2％的O 2/N 2气氛中煅烧约12h。将煅烧后的粉末产品与0.005mol纳米Li 1.3Al 0.3Ti 1.7(PO 3) 3置于行星式球磨机中充分研磨混合约10h，随后置于约670℃煅烧炉、氧含量1％的O 2/N 2气氛中煅烧约10h，得到正极材料，化学式如下式所示：
0.545Li 2MnO 2.995F 0.005·0.45Li 0.99Ni 0.444Co 0.444Mn 0.122O 1.995F 0.005·0.005Li 1.3Al 0.3Ti 1.7(PO 4) 3
该正极材料颗粒的粒径分布为4–15μm，壳层厚度为100nm。
实施例2
将1mol的Ni 0.2Co 0.2Mn 0.6CO 3置于约700℃煅烧炉、氧含量2％的O 2/N 2气氛中煅烧约8h，然后与1.529mol的LiOH·H 2O和0.00497mol的NH 4F置于研磨中充分研磨混合，随后置于约820℃煅烧炉、氧含量2％的O 2/N 2气氛中煅烧约12h。将煅烧后的粉末样品与0.006mol纳米TiO 2置于行星式球磨机研磨混合10h，随后置于约850℃煅烧炉、氧含量2％的O 2/N 2气氛中煅烧约10h，煅烧完成后取出与0.005mol纳米Li 1.3Al 0.3Ti 1.7(PO 3) 3置于行星式球磨机中充分研磨混合10h，随后置于约670℃煅烧炉、氧含量1％的O 2/N 2气氛中煅烧约10h，得到正极材料，化学式如下式所示：
0.545Li 2Mn 0.989Ti 0.011O 2.995F 0.005·0.45Li 0.976Ni 0.444Co 0.444Mn 0.136O 1.995F 0.005·0.005Li 1.3Al 0.3Ti 1.7(PO 4) 3
该正极材料颗粒的粒径分布为4–15μm，壳层厚度为100nm。
实施例3
将1mol的Ni 0.2Co 0.2Mn 0.6CO 3置于约700℃煅烧炉、氧含量2％的O 2/N 2气氛中煅烧约8h，然后与1.534mol的LiOH·H 2O和0.00497mol的NH 4F置于研磨中充分研磨混合，随后置于约820℃煅烧炉、氧含量2％的O 2/N 2气氛中煅烧约12h。将煅烧后的粉末样品与0.006mol纳米TiO 2置于行星式球磨机研磨混合10h，随后置于约850℃煅烧炉、2％O 2/N 2煅烧约10h。将煅烧后的粉末样品与0.0065mol的Li 2CO 3、0.0145mol的Al(OH) 3、0.008mol的TiO 2、0.015mol的(NH 4)H 2PO 4置于行星式球磨机中充分研磨混合10h，随后置于约1255℃煅烧炉、氧含量1％的O 2/N 2气氛中煅烧约10h，得到正极材料，化学式如下式所示：
0.545Li 2Mn 0.989Ti 0.011O 2.995F 0.005·0.45Li 0.976Ni 0.444Co 0.444Mn 0.136O 1.995F 0.005·0.005Li 1.3Al 0.3Ti 1.7(PO 4) 3
该正极材料颗粒的粒径分布为4–15μm，壳层厚度为450nm。
实施例4
将1mol的Ni 0.2Co 0.2Mn 0.6CO 3置于约300℃煅烧炉、氧含量2％的O 2/N 2气氛中煅烧约12h，然后与1.535mol的LiOH·H 2O和0.00495mol的NH 4F置于研磨中充分研磨混合，随后置于约820℃煅烧炉、氧含量2％的O 2/N 2气氛中煅烧约10h。将煅烧后的粉末产品与0.005mol纳米Li 1.3Al 0.3Ge 1.7(PO 3) 3置于行星式球磨机中充分研磨混合约10h，随后置于约700℃煅烧炉、氧含量1％的O 2/N 2气氛中煅烧约12h，得到正极材料，化学式如下式所示：
0.545Li 2MnO 2.995F 0.005·0.45Li 0.99Ni 0.444Co 0.444Mn 0.122O 1.995F 0.005·0.005Li 1.3Al 0.3Ge 1.7(PO 4) 3
该正极材料颗粒的粒径分布为4–15μm，壳层厚度为200nm。
实施例5
将1mol的Ni 0.2Co 0.2Mn 0.6CO 3置于约800℃煅烧炉、氧含量2％的O 2/N 2气氛中煅烧约4h，然后与1.535mol的LiOH·H 2O和0.00495mol的NH 4F置于研磨中充分研磨混合，随后置于约820℃煅烧炉、氧含量2％的O 2/N 2气氛中煅烧约24h。将煅烧后的粉末产品与0.005mol纳米LiTi 2(PO 4) 3置于行星式球磨机中充分 研磨混合约10h，随后置于约900℃煅烧炉、氧含量1％的O 2/N 2气氛中煅烧约1h，得到正极材料，化学式如下式所示：
0.545Li 2MnO 2.995F 0.005·0.45Li 0.99Ni 0.444Co 0.444Mn 0.122O 1.995F 0.005·0.005LiTi 2(PO 4) 3
该正极材料颗粒的粒径分布为4–15μm，壳层厚度为550nm。
实施例6
将1mol的LiFePO 4与0.004mol纳米LiTi 2(PO 4) 3置于行星式球磨机中充分研磨混合约10h，随后置于约900℃煅烧炉、氧含量1％的O 2/N 2气氛中煅烧约1h，得到正极材料，化学式如下式所示：
LiFePO 4·0.004LiTi 2(PO 4) 3
该正极材料颗粒的粒径分布为4–15μm，壳层厚度为550nm。
实施例7
将1mol的LiNi 0.8Co 0.1Mn 0.1O 2与0.003mol纳米LiTi 2(PO 4) 3置于行星式球磨机中充分研磨混合约10h，随后置于约900℃煅烧炉、氧含量1％的O 2/N 2气氛中煅烧约1h，得到正极材料，化学式如下式所示：
LiNi 0.8Co 0.1Mn 0.1O 2·0.003LiTi 2(PO 4) 3
该正极材料颗粒的粒径分布为4–15μm，壳层厚度为550nm。
对比例
将1mol的Ni 0.2Co 0.2Mn 0.6CO 3置于约700℃煅烧炉、氧含量2％的O 2/N 2气氛中煅烧8h左右，然后与1.55mol的LiOH·H 2O和0.005mol的NH 4F置于研磨中充分研磨混合，随后置于约820℃煅烧炉、氧含量2％的O 2/N 2气氛中煅烧约12h。将固体粉末取出后置于研钵中充分研磨，得到富锂锰基正极材料，化学式如下式所示：
0.55Li 2MnO 2.995F 0.005·0.45Li 1.001Ni 0.444Co 0.444Mn 0.111O 1.995F 0.005
该正极材料颗粒的粒径分布为1–17μm。
电性能测试：
在充满氩气的手套箱中用锂金属片组装扣式电池。正极极片由92wt％活性物质(即前面制备的正极材料)、4wt％Super-P导电剂和4wt％的PVDF粘结剂组成。电解液由1M LiPF 6、相同体积的碳酸亚乙酯ethylene carbonate和碳酸二甲酯dimethyl carbonate、以及相应添加剂配制而成。
首次充放电的测试制度为电压窗口为2-4.8V、充放电倍率为0.1C；倍率性能分别在0.1C、0.2C、0.5C、1C和2C的放电倍率下测试，电压窗口为2-4.6V。
图1示出了对比例和实施例1中的正极材料的首次充放电曲线。
图2示出了对比例和实施例2中的正极材料的首次充放电曲线。
图3示出了对比例和实施例3中的正极材料的首次充放电曲线。
图4示出了对比例和实施例1中的正极材料的倍率性能测试结果。
图5示出了对比例和实施例2中的正极材料的倍率性能测试结果。
图6示出了对比例和实施例3中的正极材料的倍率性能测试结果。
图7示出了对比例和实施例1中的正极材料的循环性能测试结果。
图8示出了对比例和实施例2中的正极材料的循环性能测试结果。
图9示出了对比例和实施例3中的正极材料的循环性能测试结果。
由上述结果可知，实施例1-3对应的首次充电比容量介于340–360mAh/g之间，放电比容量介于300–330mAh/g之间。
由图1可知，本公开实施例的正极材料可以将富锂锰基正极材料的放电比容量提高4.5％。
由图2可知，对比例中富锂锰基正极材料的首次充电比容量和放电比容量分别346.9mAh/g和308.7mAh/g，首次库伦效率为88.98％；实施例2中正极材料的首次充电比容量和放电比容量分别为382.8mAh/g和341mAh/g，首次库伦 效率为89.10％。本公开实施例的正极材料能够大幅改善放电比容量，提升约10.5％。
由图3可知，实施例3对应的首次充电比容量和放电比容量分别为348.6mAh/g和300.8mAh/g，首次库伦效率为86.3％。相比对比例，放电比容量和库伦效率有所降低。
由图4可知，实施例1制备的正极材料在大电流条件下的放电比容量在一定程度上得到了改善，其中1C倍率下放电比容量为240.1mAh/g，此条件下对比例具有的放电比容量为231.1mAh/g。
由图5可知，实施例2制备的正极材料在1C倍率下的放电比容量达到了253mAh/g，相比对比例的1C倍率性能得到了显著的改善，该数据将是正极材料领域一个重要的技术突破。
由图6可知，实施例3制备的正极材料在1C和2C倍率条件下放电比容量有所降低，比容量分别为227.5和208.5mAh/g，说明采用含Ti化合物、含Al化合物、含P化合物等与基体颗粒混合，通过高温固相反应在基体颗粒表面形成外壳的合成路径，容易导致副反应生成杂相，降低了外壳锂离子的扩散系数和导电率。
由图7可知，对比例和实施例1在经过50个充/放电循环后，容量保持率分别为81.5％和86.2％。实施例1在循环容量保持率方面提高了5.8％。
由图8可知，实施例2制备的正极材料在经过50个充/放电循环后，容量保持率86.4％。相比对比例，其循环容量保持率提高了6.0％。
由图9可知，实施例3对应的循环容量保持率为87.6％，较对比例提高了7.5％，说明虽然制备工艺存在一定影响，但是外壳材料的选择仍会提高正极材料的电化学性能。
实施例4的产品的首次充电比容量和放电比容量分别为315mAh/g，1C倍率下放电比容量为236mAh/g；经过50个充/放电循环后，容量保持率为85.4％。
实施例5的产品的首次充电比容量和放电比容量分别为311mAh/g，1C倍率下放电比容量为232mAh/g；经过50个充/放电循环后，容量保持率为85.9％。
实施例6的产品的首次充电比容量和放电比容量分别为151mAh/g，1C倍率下放电比容量为144mAh/g；经过50个充/放电循环后，容量保持率为99.1％。该实施例正极基体材料为磷酸铁锂，该材料本身克容量很低，另外循环稳定性却非常高。
实施例7的产品的首次充电比容量和放电比容量分别为209mAh/g，1C倍率下放电比容量为189mAh/g；经过50个充/放电循环后，容量保持率为89.6％。该实施例为高镍三元材料，放电克容量介于富理锰基正极材料与磷酸铁锂正极材料之间，循环容量保持率也是同样。

Claims (13)

  1. 一种正极材料，其包括：
    基体颗粒，形成所述基体颗粒的材料包括富锂锰基材料、镍钴锰酸锂、镍钴铝酸锂、磷酸铁锂、锰酸锂、镍钴锰铝酸锂和镍锰酸锂中的至少一种；及
    外壳，所述外壳包覆在所述基体颗粒的至少一部分外表面上，形成所述外壳的材料包括磷酸钛锂、磷酸锗铝锂和磷酸钛铝锂中的至少一种。
  2. 根据权利要求1所述的正极材料，其中，所述外壳的厚度为0～500nm，且不为0。
  3. 根据权利要求2所述的正极材料，其中，所述外壳的厚度为0～200nm，且不为0。
  4. 根据权利要求3所述的正极材料，其中，所述外壳的厚度为0～100nm，且不为0。
  5. 根据权利要求1-4中任一项所述的正极材料，其中，所述正极材料的粒径分布为1～17微米。
  6. 根据权利要求5所述的正极材料，其中，所述正极材料的粒径分布为4～15微米。
  7. 根据权利要求1-6中任一项所述的正极材料，其中，形成基体颗粒的材料为所述富锂锰基材料，所述正极材料的化学组成为：
    aLi 2+αMn 1-μTi μO 3-νF ν·bLi 1+α'MO 2-ν'F ν'·cLi 1+α”Al βM' 2-β(PO 4) 3，
    其中，a+b+c＝1，0<a<0.6，0<b<0.5，0<c≤0.05，0≤α≤0.04，0<μ≤0.5，0.005≤ν≤0.02，0≤α'≤0.04，-0.02≤α”<1，0.005≤ν'≤0.02，0≤β<0.5，
    M为Ni、Co、Mn、Al、Mg、Ti、Zr、Zn、Ca、B、Ce和Cr等中的至少一种元素，
    M'为Ti、Ge中的至少一种元素。
  8. 根据权利要求7所述的正极材料，其中，所述正极材料包括以下的至少一种：
    0.545Li 2MnO 2.995F 0.005·0.45Li 0.99Ni 0.444Co 0.444Mn 0.122O 1.995F 0.005·0.005Li 1.3Al 0.3Ti 1.7(PO 4) 3，
    0.545Li 2Mn 0.989Ti 0.011O 2.995F 0.005·0.45Li 0.976Ni 0.444Co 0.444Mn 0.136O 1.995F 0.005·0.005Li 1.3Al 0.3Ti 1.7(PO 4) 3，和
    0.545Li 2Mn 0.989Ti 0.011O 2.995F 0.005·0.45Li 0.976Ni 0.444Co 0.444Mn 0.136O 1.995F 0.005·0.005 Li 1.3Al 0.3Ti 1.7(PO 4) 3。
  9. 根据权利要求1所述的正极材料，其特征在于，所述正极材料满足以下条件的至少之一：
    0.1C倍率放电比容量大于等于280mAh/g；
    1C倍率放电比容量大于等于220mAh/g；
    50周充放电循环后容量保持率大于等于85％。
  10. 一种制备权利要求1-9中任一项所述的正极材料的方法，其包括：
    将基体颗粒和外壳原料的混合物球磨1-10小时，得到混合材料，
    将所述混合材料于300–900℃、O 2/N 2气氛下煅烧1–12h，得到正极材料，
    其中，所述外壳原料为纳米磷酸钛锂、纳米磷酸锗铝锂或者纳米磷酸钛铝锂。
  11. 根据权利要求10所述的方法，其中，所述基体颗粒是通过以下方法一或方法二制备的：
    方法一：将前驱体材料于300–800℃、O 2/N 2气氛下煅烧4–12h，得到第一煅烧产物，
    将所述第一煅烧产物与锂源混合，并将得到的混合物于600–950℃、O 2/N 2气氛下煅烧10–24h，得到所述基体颗粒；
    方法二：将前驱体材料于300–800℃、O 2/N 2气氛下煅烧4–12h，得到所述第一煅烧产物，
    将所述第一煅烧产物与所述锂源混合，并将得到的混合物于600–950℃、O 2/N 2气氛下煅烧10–24h，得到第二煅烧产物；
    将所述第二煅烧产物与纳米TiO 2的混合物球磨2–8h后，于750–850℃、O 2/N 2气氛下煅烧4–16h，得到所述基体颗粒。
  12. 一种锂离子电池，其包括权利要求1-9中任一项所述的正极材料。
  13. 一种电动汽车，其包括权利要求12所述的锂离子电池。
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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115367816A (zh) * 2022-10-27 2022-11-22 宜宾锂宝新材料有限公司 一种镍锰酸锂正极材料、其制备方法及锂离子电池
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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
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EP4228033A1 (en) 2021-12-29 2023-08-16 Contemporary Amperex Technology Co., Limited Positive electrode active material and preparation method therefor, secondary battery, and electric device
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KR20240057133A (ko) * 2022-10-24 2024-05-02 주식회사 에코프로비엠 양극 활물질 및 이를 포함하는 리튬 이차전지
CN115719802A (zh) * 2022-11-24 2023-02-28 天津巴莫科技有限责任公司 包覆型正极材料及其制备方法、二次电池和正极、用电装置
CN115995276B (zh) * 2023-03-22 2023-05-23 四川新能源汽车创新中心有限公司 锂电池极片面密度的确定方法、装置以及计算机终端
CN116682972A (zh) * 2023-06-16 2023-09-01 长沙理工大学 一种硒和磷酸钛铝锂双重修饰的富锂锰正极材料及其制备方法
CN117133920B (zh) * 2023-10-25 2023-12-29 成都仪隆电子有限公司 改性磷酸铁锰锂正极材料及其制备方法和应用

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107492643A (zh) * 2017-07-31 2017-12-19 三峡大学 一种磷酸钛锂包覆LiNi1/3Co1/3Mn1/3O2正极材料及其制备方法
CN107591529A (zh) * 2017-10-10 2018-01-16 中南大学 一种磷酸钛锂包覆镍钴锰三元正极材料及其制备方法
CN107768631A (zh) * 2017-10-16 2018-03-06 桑顿新能源科技有限公司 一种包覆磷酸钛铝锂的富锂锰基材料及其制备方法
CN109119624A (zh) * 2018-09-28 2019-01-01 中南大学 一种磷酸钛锂包覆富锂锰基正极材料的制备方法
CN109904424A (zh) * 2019-02-28 2019-06-18 河南大学 一步法表面包覆和梯度掺杂一体化双修饰lnmo正极材料的方法
CN110112383A (zh) * 2019-04-17 2019-08-09 湖北锂诺新能源科技有限公司 磷酸钛铝锂包覆的高镍三元正极材料及其制备方法
CN111435737A (zh) * 2020-03-31 2020-07-21 蜂巢能源科技有限公司 正极材料及其制备方法、锂离子电池和电动汽车

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107492643A (zh) * 2017-07-31 2017-12-19 三峡大学 一种磷酸钛锂包覆LiNi1/3Co1/3Mn1/3O2正极材料及其制备方法
CN107591529A (zh) * 2017-10-10 2018-01-16 中南大学 一种磷酸钛锂包覆镍钴锰三元正极材料及其制备方法
CN107768631A (zh) * 2017-10-16 2018-03-06 桑顿新能源科技有限公司 一种包覆磷酸钛铝锂的富锂锰基材料及其制备方法
CN109119624A (zh) * 2018-09-28 2019-01-01 中南大学 一种磷酸钛锂包覆富锂锰基正极材料的制备方法
CN109904424A (zh) * 2019-02-28 2019-06-18 河南大学 一步法表面包覆和梯度掺杂一体化双修饰lnmo正极材料的方法
CN110112383A (zh) * 2019-04-17 2019-08-09 湖北锂诺新能源科技有限公司 磷酸钛铝锂包覆的高镍三元正极材料及其制备方法
CN111435737A (zh) * 2020-03-31 2020-07-21 蜂巢能源科技有限公司 正极材料及其制备方法、锂离子电池和电动汽车

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115367816A (zh) * 2022-10-27 2022-11-22 宜宾锂宝新材料有限公司 一种镍锰酸锂正极材料、其制备方法及锂离子电池
CN115676799A (zh) * 2022-12-28 2023-02-03 湖南鹏博新材料有限公司 改性磷酸铁锂的制备方法
CN115676799B (zh) * 2022-12-28 2023-03-31 湖南鹏博新材料有限公司 改性磷酸铁锂的制备方法
CN116332623A (zh) * 2023-03-27 2023-06-27 深圳市众诚达应用材料科技有限公司 一种nmo氧化物半导体材料及其制备方法和应用
CN116332623B (zh) * 2023-03-27 2024-06-11 深圳众诚达应用材料股份有限公司 一种nmo氧化物半导体材料及其制备方法和应用

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