WO2023142335A1 - 三元正极材料前驱体及其制备方法、三元正极材料、锂离子电池及正极和涉电设备 - Google Patents

三元正极材料前驱体及其制备方法、三元正极材料、锂离子电池及正极和涉电设备 Download PDF

Info

Publication number
WO2023142335A1
WO2023142335A1 PCT/CN2022/098559 CN2022098559W WO2023142335A1 WO 2023142335 A1 WO2023142335 A1 WO 2023142335A1 CN 2022098559 W CN2022098559 W CN 2022098559W WO 2023142335 A1 WO2023142335 A1 WO 2023142335A1
Authority
WO
WIPO (PCT)
Prior art keywords
reaction
layer
ternary
positive electrode
porosity
Prior art date
Application number
PCT/CN2022/098559
Other languages
English (en)
French (fr)
Inventor
訚硕
纪方力
余忠高
尹伟
任永志
伍兴科
张勤
常海珍
阎晓静
Original Assignee
中伟新材料股份有限公司
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 中伟新材料股份有限公司 filed Critical 中伟新材料股份有限公司
Priority to JP2023532305A priority Critical patent/JP2024507033A/ja
Priority to KR1020237020168A priority patent/KR20230117359A/ko
Publication of WO2023142335A1 publication Critical patent/WO2023142335A1/zh
Priority to US18/467,413 priority patent/US20230416110A1/en

Links

Images

Classifications

    • CCHEMISTRY; METALLURGY
    • C01INORGANIC CHEMISTRY
    • C01GCOMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
    • C01G53/00Compounds of nickel
    • C01G53/006Compounds containing, besides nickel, two or more other elements, with the exception of oxygen or hydrogen
    • CCHEMISTRY; METALLURGY
    • C01INORGANIC CHEMISTRY
    • C01GCOMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
    • C01G53/00Compounds of nickel
    • C01G53/04Oxides; Hydroxides
    • CCHEMISTRY; METALLURGY
    • C01INORGANIC CHEMISTRY
    • C01GCOMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
    • C01G53/00Compounds of nickel
    • CCHEMISTRY; METALLURGY
    • C01INORGANIC CHEMISTRY
    • C01GCOMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
    • C01G53/00Compounds of nickel
    • C01G53/40Nickelates
    • C01G53/42Nickelates containing alkali metals, e.g. LiNiO2
    • C01G53/44Nickelates containing alkali metals, e.g. LiNiO2 containing manganese
    • CCHEMISTRY; METALLURGY
    • C01INORGANIC CHEMISTRY
    • C01GCOMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
    • C01G53/00Compounds of nickel
    • C01G53/40Nickelates
    • C01G53/42Nickelates containing alkali metals, e.g. LiNiO2
    • C01G53/44Nickelates containing alkali metals, e.g. LiNiO2 containing manganese
    • C01G53/50Nickelates containing alkali metals, e.g. LiNiO2 containing manganese of the type [MnO2]n-, e.g. Li(NixMn1-x)O2, Li(MyNixMn1-x-y)O2
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00Secondary cells; Manufacture thereof
    • H01M10/05Accumulators with non-aqueous electrolyte
    • H01M10/052Li-accumulators
    • H01M10/0525Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00Electrodes
    • H01M4/02Electrodes composed of, or comprising, active material
    • H01M4/13Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00Electrodes
    • H01M4/02Electrodes composed of, or comprising, active material
    • H01M4/13Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
    • H01M4/131Electrodes based on mixed oxides or hydroxides, or on mixtures of oxides or hydroxides, e.g. LiCoOx
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00Electrodes
    • H01M4/02Electrodes composed of, or comprising, active material
    • H01M4/36Selection of substances as active materials, active masses, active liquids
    • H01M4/362Composites
    • H01M4/366Composites as layered products
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00Electrodes
    • H01M4/02Electrodes composed of, or comprising, active material
    • H01M4/36Selection of substances as active materials, active masses, active liquids
    • H01M4/48Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides
    • H01M4/50Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of manganese
    • H01M4/505Selection 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
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00Electrodes
    • H01M4/02Electrodes composed of, or comprising, active material
    • H01M4/36Selection of substances as active materials, active masses, active liquids
    • H01M4/48Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides
    • H01M4/52Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of nickel, cobalt or iron
    • H01M4/525Selection 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
    • CCHEMISTRY; METALLURGY
    • C01INORGANIC CHEMISTRY
    • C01PINDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2002/00Crystal-structural characteristics
    • C01P2002/70Crystal-structural characteristics defined by measured X-ray, neutron or electron diffraction data
    • C01P2002/72Crystal-structural characteristics defined by measured X-ray, neutron or electron diffraction data by d-values or two theta-values, e.g. as X-ray diagram
    • CCHEMISTRY; METALLURGY
    • C01INORGANIC CHEMISTRY
    • C01PINDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2004/00Particle morphology
    • C01P2004/01Particle morphology depicted by an image
    • C01P2004/03Particle morphology depicted by an image obtained by SEM
    • CCHEMISTRY; METALLURGY
    • C01INORGANIC CHEMISTRY
    • C01PINDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2004/00Particle morphology
    • C01P2004/10Particle morphology extending in one dimension, e.g. needle-like
    • CCHEMISTRY; METALLURGY
    • C01INORGANIC CHEMISTRY
    • C01PINDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2004/00Particle morphology
    • C01P2004/60Particles characterised by their size
    • C01P2004/61Micrometer sized, i.e. from 1-100 micrometer
    • CCHEMISTRY; METALLURGY
    • C01INORGANIC CHEMISTRY
    • C01PINDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2006/00Physical properties of inorganic compounds
    • C01P2006/14Pore volume
    • CCHEMISTRY; METALLURGY
    • C01INORGANIC CHEMISTRY
    • C01PINDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2006/00Physical properties of inorganic compounds
    • C01P2006/40Electric properties
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00Electrodes
    • H01M4/02Electrodes composed of, or comprising, active material
    • H01M2004/021Physical characteristics, e.g. porosity, surface area
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00Electrodes
    • H01M4/02Electrodes composed of, or comprising, active material
    • H01M2004/026Electrodes composed of, or comprising, active material characterised by the polarity
    • H01M2004/028Positive electrodes
    • YGENERAL 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
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02EREDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10Energy storage using batteries

Definitions

  • the present application relates to the field of lithium-ion batteries, in particular to a precursor of a ternary positive electrode material and a preparation method thereof, a ternary positive electrode material, a lithium-ion battery, a positive electrode, and electrical equipment.
  • high-nickel large-particle precursors are generally synthesized by a batch method, with a very narrow particle size distribution, which can also make the particle structure uniform powerful.
  • the interior of the ternary precursor particles is generally a dense structure with few pores, and the internal distribution is uneven; the battery prepared by the ternary precursor particles has a single lithium ion diffusion path and a large diffusion resistance. Insufficient rate performance; moreover, the battery has always had the problem that with repeated charging and discharging, the unstable particle structure strength will easily cause cracks in the particle unit, resulting in shorter life and lower capacity of lithium secondary batteries. Poor safety performance.
  • the purpose of the present application is to provide a precursor of a ternary cathode material and its preparation method, a ternary cathode material, a lithium-ion battery, a cathode and electrical equipment, so as to solve the above problems.
  • a ternary cathode material precursor comprising a core layer, a first intermediate layer, a second intermediate layer, and a shell layer in sequence from the inside to the outside, the core layer, the first intermediate layer, and the second intermediate layer
  • the porosity increases sequentially, with the shell having minimal or no porosity.
  • the porosity of the core layer is 1.40%-7.96%
  • the porosity of the first intermediate layer is 2.10%-8.37%
  • the porosity of the second intermediate layer is 4.57%-16.72%.
  • the porosity of the shell layer is less than or equal to 1%;
  • the porosity of the core layer is 2.0%-4.0%
  • the porosity of the first intermediate layer is 3.0%-5.0%
  • the porosity of the second intermediate layer is 7.35%-10.32%.
  • the porosity of the shell layer is less than or equal to 0.5%.
  • the average thickness of each layer of the ternary cathode material precursor is less than or equal to 3 ⁇ m;
  • the diameter of the core layer is 1.0 ⁇ m-3.0 ⁇ m
  • the average thickness of the first intermediate layer is 0.2 ⁇ m-2.0 ⁇ m
  • the average thickness of the second intermediate layer is 1 ⁇ m-2.5 ⁇ m
  • the shell The average thickness of the layer is between 0.5 ⁇ m and 1.5 ⁇ m.
  • the primary particles in the precursor of the ternary positive electrode material are distributed in a loose intersecting needle shape along its radial direction, from the inside to the outside;
  • the core layer is generally spherical
  • the primary particles in the shell layer are needle-shaped along the radial direction of the ternary cathode material precursor
  • the average particle size of the ternary cathode material precursor is 12 ⁇ m-15 ⁇ m;
  • D95/D50 1.0-1.6;
  • the BET of the ternary cathode material precursor is 11m 2 /g-17m 2 /g.
  • the half-width ⁇ of the 001 peak whose diffraction angle 2 ⁇ is 19.2 ⁇ 1° is less than or equal to 0.6;
  • the half-peak width ⁇ is 0.43-0.53;
  • the half-width ⁇ of the 101 peak whose diffraction angle 2 ⁇ is in the range of 38.5 ⁇ 1° is less than or equal to 0.7;
  • the half-peak width ⁇ is 0.48-0.58;
  • the ratio of the half-peak width ⁇ to the half-peak width ⁇ is greater than or equal to 1.02, and the peak intensity ratio I(001/101) is 1.0-1.2;
  • the ratio of the half-peak width ⁇ to the half-peak width ⁇ is 1.02-1.25.
  • the present application also provides a method for preparing the precursor of the ternary cathode material, including:
  • the first reaction, the second reaction, the third reaction, and the fourth reaction are all carried out under stirring, and the stirring speed decreases sequentially;
  • the stirring speed of the first reaction is 200r/min-240r/min
  • the stirring speed of the second reaction is 180r/min-230r/min
  • the stirring speed of the third reaction is 100r/min- 200r/min
  • the stirring speed of the fourth reaction is 40r/min-100r/min.
  • the addition amount of the nickel-cobalt-manganese ternary mixed solution increases sequentially;
  • the addition amount of the nickel-cobalt-manganese ternary mixed solution is 80L/h-550L/h; in the process of the second reaction, the nickel-cobalt-manganese ternary mixed solution The addition amount of the solution is 150L/h-650L/h; in the process of the third reaction and the fourth reaction, the addition amount of the nickel-cobalt-manganese ternary mixed solution is 150L/h-750L/h;
  • the addition amount of the nickel-cobalt-manganese ternary mixed solution is in steps formula increase;
  • the stepwise increase ratio is 10%-100%.
  • the pH of the system gradually decreases; during the fourth reaction, the pH of the system is higher than that of the third reaction;
  • the pH of the system is in the range of 10-12;
  • the pH of the system is higher than that of the third reaction by 0.10-0.30.
  • the concentration of the nickel-cobalt-manganese ternary mixed solution is 90-130g/L;
  • the complexing agent includes one or more of ammonia water, EDTA, ethylenediamine, sodium citrate, and urea;
  • the complexing agent is ammonia water with a mass fraction of 15%-35%;
  • the concentration of ammonia in the system is 2.5g/L-6.5g/L;
  • the concentration of ammonia water in the system is 1.0-3.0 g/l higher than the concentration of ammonia water in the second reaction process;
  • the pH regulator includes one or more of sodium hydroxide, potassium hydroxide, sodium bicarbonate, and soda ash;
  • the pH regulator is an aqueous sodium hydroxide solution with a mass fraction of 25%-50%.
  • the present application also provides a ternary positive electrode material, which includes layer A, layer B, layer C, and layer D sequentially from the inside to the outside, and the porosity of the layer A, the layer B, and the layer C increases sequentially,
  • the D layer has minimal or no porosity
  • the ternary cathode material is obtained by firing the precursor of the ternary cathode material.
  • the present application also provides a positive electrode of a lithium ion battery, including the ternary positive electrode material.
  • the present application also provides a lithium ion battery, including the positive electrode of the lithium ion battery.
  • the present application also provides an electrical device, including the lithium-ion battery.
  • the ternary cathode material precursor provided by this application compared with the current ternary precursor with a dense internal structure, the ternary precursor includes a core layer, a first intermediate layer, a second intermediate layer and a shell layer in sequence from the inside to the outside,
  • the porosity of the core layer, the first intermediate layer, and the second intermediate layer increases sequentially, and the porosity of the shell layer is minimal or non-porous;
  • the porosity of the inner three layers gradually increases, and this structure forms Relatively more diffusion paths, more lithium ion transmission channels, reduce the diffusion resistance of lithium ions, effectively increase the diffusion rate of lithium ions, thereby improving charge and discharge performance, rate performance, and cycle performance; shell porosity is minimal or non-porous, It is a dense and less porous shell structure, which shows a loose inner and outer tight shape, which can withstand the stress generated by charging and discharging.
  • the dense and less porous shell can protect the structural stability; and the internal structure of the ternary precursor of the positive electrode material meets the structural requirements.
  • a certain range of porosity and a less porous and dense structure of the shell improve the strength of the particles.
  • the particles are not easy to crack, thereby increasing the cycle retention rate and life of the battery, and the battery performance is excellent.
  • the preparation method of the precursor of the ternary positive electrode material provided by this application can be stably prepared by the solution co-precipitation method through the first reaction, the second reaction, the third reaction and the fourth reaction to obtain the above-mentioned ternary positive electrode with a special four-layer structure Material precursor, low cost, stable process.
  • the ternary positive electrode material, lithium ion battery positive electrode, and lithium ion battery provided by the application have good electrical performance, long service life, and high safety and stability.
  • Fig. 1 is the structural representation of the precursor of ternary cathode material provided by the present application
  • Fig. 2 is the cross-sectional SEM photograph of the ternary positive electrode material precursor that embodiment 1 obtains;
  • Fig. 3 is the high magnification electron micrograph of the ternary cathode material precursor that embodiment 1 obtains;
  • Fig. 4 is the local high-magnification electron micrograph of the ternary cathode material precursor that embodiment 1 obtains;
  • Fig. 5 is the high magnification electron micrograph of the ternary cathode material precursor that embodiment 2 obtains;
  • Fig. 6 is the local high-magnification electron microscope of the ternary cathode material precursor that embodiment 2 obtains;
  • Fig. 7 is the XRD spectrum of the ternary cathode material precursor that embodiment 1,2,3,4 obtains;
  • Fig. 8 is the cross-sectional SEM photograph of the ternary positive electrode material precursor that embodiment 2 obtains;
  • Figure 9 is a cross-sectional SEM photo of the ternary cathode material precursor obtained in Example 3.
  • Fig. 10 is the cross-sectional SEM photo of the ternary cathode material precursor obtained in Example 4.
  • Fig. 12 is the high magnification electron microscope photo of the ternary cathode material precursor obtained in comparative example 1;
  • Figure 13 is a local high-magnification electron microscope photo of the ternary cathode material precursor obtained in Comparative Example 1;
  • Figure 14 is the XRD spectrum of the ternary cathode material precursor obtained in Comparative Example 1;
  • Figure 15 is a cross-sectional SEM photo of the ternary cathode material precursor obtained in Comparative Example 2;
  • Figure 16 is the XRD spectrum of the ternary cathode material precursor obtained in Comparative Example 2;
  • Figure 18 is the XRD spectrum of the ternary cathode material precursor obtained in Comparative Example 3.
  • compositions are synonymous with “comprising”.
  • the terms “comprises,” “including,” “has,” “containing,” or any other variation thereof, are intended to cover a non-exclusive inclusion.
  • a composition, step, method, article, or device comprising listed elements is not necessarily limited to those elements, but may include other elements not explicitly listed or inherent to such composition, step, method, article, or device. elements.
  • Parts by mass refers to the basic measurement unit that expresses the mass ratio relationship of multiple components, and 1 part can represent any unit mass, such as 1g or 2.689g. If we say that the mass part of A component is a part, and the mass part of B component is b part, it means that the mass ratio of A component to B component is a:b. Alternatively, it means that the mass of component A is aK, and the mass of component B is bK (K is an arbitrary number, representing a multiple factor). It should not be misunderstood that, unlike the parts by mass, the sum of parts by mass of all components is not limited to 100 parts.
  • a and/or B includes (A and B) and (A or B).
  • the present application provides a kind of ternary cathode material precursor, comprises core layer (a core), first intermediate layer (b porous second layer), second intermediate layer (c porous) from inside to outside The third layer) and the shell layer (d shell layer), the porosity of the core layer, the first intermediate layer, and the second intermediate layer increase sequentially, and the porosity of the shell layer is minimal or non-porous.
  • the first intermediate layer is outside the core layer and covers the core layer
  • the second intermediate layer is outside the first intermediate layer and covers the first intermediate layer and the core layer
  • the shell layer is the outermost layer, covering The second intermediate layer and the first intermediate layer and core layer therein.
  • the porosity of the core layer is 1.40%-7.96%
  • the porosity of the first intermediate layer is 2.10%-8.37%
  • the porosity of the second intermediate layer is 4.57%. %-16.72%
  • the porosity of the shell layer is less than or equal to 1%
  • the porosity of the core layer is 2.0%-4.0%
  • the porosity of the first intermediate layer is 3.0%-5.0%
  • the porosity of the second intermediate layer is 7.35% %-10.32%
  • the porosity of the shell layer is less than or equal to 0.5%.
  • imageJ image analysis software
  • the porosity of the three layers inside the precursor of the ternary cathode material gradually increases to meet the above porosity range.
  • This structure forms relatively more diffusion paths and more lithium ion transmission channels, which reduces the diffusion resistance of lithium ions and effectively improves the lithium ion density. Diffusion rate, thereby improving charge and discharge performance, rate performance, and cycle performance; shell porosity is minimal or non-porous, and it is a dense and less porous shell structure, which shows a shape of inner looseness and outer tightness, which can withstand the shock generated by charging and discharging.
  • the dense and less porous shell can protect the structural stability; moreover, the internal structure of the ternary precursor of the positive electrode material satisfies a certain range of porosity of the structure and the shell has a less porous and dense structure, which improves the strength of the particles.
  • the particles are not easy to Cracking, thereby increasing the cycle retention rate and lifespan, and the battery has excellent performance.
  • the porosity of the core layer can be 1.40%, 2%, 3%, 4%, 5%, 6%, 7%, 7.96% or any value between 1.40%-7.96%, so
  • the porosity of the first intermediate layer can be 2.10%, 3%, 4%, 5%, 6%, 7%, 8%, 8.37% or any value between 2.10%-8.37%
  • the second The porosity of the middle layer can be 4.57%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, 16%, 16.72% or 4.57% Any value between %-16.72%
  • the porosity of the shell can be 0.05%, 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1% or any value less than or equal to 1%.
  • the average thickness of each layer of the ternary cathode material precursor is less than or equal to 3 ⁇ m;
  • the diameter of the core layer is 1.0 ⁇ m-3.0 ⁇ m
  • the average thickness of the first intermediate layer is 0.2 ⁇ m-2.0 ⁇ m
  • the average thickness of the second intermediate layer is 1 ⁇ m- 2.5 ⁇ m
  • the average thickness of the shell layer is 0.5 ⁇ m-1.5 ⁇ m
  • the diameter of the core layer may be 1.0 ⁇ m, 1.5 ⁇ m, 2 ⁇ m, 2.5 ⁇ m, 3.0 ⁇ m or any value between 1.0 ⁇ m-3.0 ⁇ m
  • the average thickness of the first intermediate layer may be 0.2 ⁇ m, 0.5 ⁇ m, 1 ⁇ m, 1.5 ⁇ m, 2.0 ⁇ m or any value between 0.2 ⁇ m-2.0 ⁇ m
  • the average thickness of the second intermediate layer can be 1 ⁇ m, 1.5 ⁇ m, 2 ⁇ m, 2.5 ⁇ m or 1 ⁇ m-2.5 ⁇ m
  • the average thickness of the shell layer can be 0.5 ⁇ m, 1 ⁇ m, 1.5 ⁇ m or any value between 0.5 ⁇ m-1.5 ⁇ m;
  • the average thickness inside the particle is determined according to the final particle size of each reaction step above.
  • the primary particles in the precursor of the ternary positive electrode material are distributed in a loose intersecting needle shape along the radial direction, from the inside to the outside;
  • the core layer is generally spherical
  • the primary particles in the shell layer are needle-shaped along the radial direction of the ternary cathode material precursor
  • the average particle size of the ternary cathode material precursor is 12 ⁇ m-15 ⁇ m;
  • D95/D50 1.0-1.6
  • D95/D50 of the ternary cathode material precursor may be 1, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6 or any value between 1-1.6.
  • the particle size of the precursor of the ternary cathode material presents a narrow distribution, the particle distribution is uniform, and the electrical performance is better.
  • the primary particles on the surface of the precursor particles of the ternary positive electrode material meet the above particle size range and particle size distribution, the primary particles are loose and needle-shaped and cross evenly distributed. It is used in the battery of the positive electrode material to reduce the diffusion resistance of lithium ions. To a certain extent Facilitate the transport of lithium ions.
  • the BET of the ternary cathode material precursor is 11m 2 /g-17m 2 /g.
  • the BET of the ternary cathode material precursor may be 11m 2 /g, 12m 2 /g, 13m 2 /g, 14m 2 /g, 15m 2 /g, 16m 2 / g, 17m 2 /g Or any value between 11m 2 /g-17m 2 /g.
  • the half-width ⁇ of the 001 peak whose diffraction angle 2 ⁇ is in the range of 19.2 ⁇ 1° is less than or equal to 0.6;
  • the half-peak width ⁇ is 0.43-0.53;
  • the half-peak width ⁇ may be 0.3, 0.4, 0.43, 0.5, 0.6 or any value less than or equal to 0.6.
  • the half-width ⁇ of the 101 peak whose diffraction angle 2 ⁇ is in the range of 38.5 ⁇ 1° is less than or equal to 0.7;
  • the half-peak width ⁇ is 0.48-0.58;
  • the half-peak width ⁇ may be 0.3, 0.4, 0.48, 0.5, 0.58, 0.6, 0.7 or any value less than or equal to 0.7.
  • the ratio of the half-peak width ⁇ to the half-peak width ⁇ is greater than or equal to 1.02, and the peak intensity ratio I(001/101) is 1.0-1.2;
  • the ratio of the half-peak width ⁇ to the half-peak width ⁇ is 1.02-1.25.
  • the ratio of the half-peak width ⁇ to the half-peak width ⁇ may be 1.02, 1.1, 1.2, 1.25 or any value between 1.0-1.25.
  • the half-peak width of the 001 plane is small, the peak intensity value is high, the particles grow preferentially on the 001 crystal plane, and the crystallinity of the 001 plane is relatively high, which affects the growth of primary particles, and the active material precursor is prepared to have excellent structural stability; and the precursor
  • the 001 peak intensity of the bulk material is stronger than the 101 peak intensity, and the crystallinity of the particles at the 001 peak is more advantageous.
  • the precursor material forms a positive electrode active material, combined with the internal structure pore distribution, it can exert excellent output characteristics, cycle performance, and rate performance. Increase battery capacity.
  • the present application also provides a method for preparing the precursor of the ternary cathode material, including:
  • the first reaction, the second reaction, the third reaction, and the fourth reaction are all carried out under stirring, and the stirring speed decreases sequentially;
  • the stirring speed of the first reaction is 200r/min-240r/min
  • the stirring speed of the second reaction is 180r/min-230r/min
  • the stirring speed of the third reaction The speed is 100r/min-200r/min
  • the stirring speed of the fourth reaction is 40r/min-100r/min.
  • the fourth reaction reduces the stirring intensity, reduces the supersaturation of the solution, and is conducive to the growth of the crystal interface, and increases the pH of the system in the fourth reaction process, which is conducive to the stability of the crystal particle strength, and then forms a dense shell structure of the crystal plane. stable structure.
  • the average thickness inside the particle is determined according to the final particle size of each reaction step above.
  • the stirring speed of the first reaction can be 200r/min, 210r/min, 220r/min, 230r/min, 240r/min or any value between 200r/min-240r/min
  • the The stirring speed of the second reaction can be any value between 180r/min, 190r/min, 200r/min, 210r/min, 220r/min, 230r/min or 180r/min-230r/min
  • the third The stirring speed of reaction can be 100r/min, 110r/min, 120r/min, 130r/min, 140r/min, 150r/min, 160r/min, 170r/min, 180r/min, 190r/min, 200r/min or Any value between 100r/min-200r/min
  • the stirring speed of the fourth reaction can be 40r/min, 50r/min, 60r/min, 70r/min, 80r/min, 90r/min, 100r/min min or any value between 40r/min-100r/min;
  • the addition amount of the nickel-cobalt-manganese ternary mixed solution increases sequentially. big;
  • the amount of the nickel-cobalt-manganese ternary mixed solution is 80L/h-550L/h; during the second reaction, the The addition amount of the nickel-cobalt-manganese ternary mixed solution is 150L/h-650L/h; during the third reaction and the fourth reaction, the added amount of the nickel-cobalt-manganese ternary mixed solution is 150L/h -750L/h;
  • the amount of the nickel-cobalt-manganese ternary mixed solution can be 80L/h, 100L/h, 200L/h, 300L/h, 400L/h, 500L/h , 550L/h or any value between 80L/h-550L/h; in the process of the second reaction, the addition amount of the nickel-cobalt-manganese ternary mixed solution can be 150L/h, 200L/h, 300L/h, 400L/h, 500L/h, 600L/h, 650L/h or any value between 150L/h-650L/h; during the third reaction and the fourth reaction, the The amount of the nickel-cobalt-manganese ternary mixed solution can be 150L/h, 200L/h, 300L/h, 400L/h, 500L/h, 600L/h, 700L/h, 750L/h or 150L/h-750L Any value between /h;
  • the nickel-cobalt-manganese ternary mixture increases stepwise;
  • the four-level structure of the precursor of the ternary cathode material is reacted again by the materials in the first, second, and third steps as seed crystals.
  • the flow rate of the ternary metal in each step increases stepwise to form a multi-layer internal porous structure, and the fourth reaction condition is adjusted.
  • a dense shell structure is formed.
  • the porosity of the internal structure of the precursor particle of the ternary cathode material is determined according to the pH value adjustment, the ammonia concentration, and the flow ratio of the raw material ternary mixed metal salt solution in each of the above steps.
  • the stepwise increase ratio is 10%-100%.
  • the stepwise increase ratio may be 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, 100% or 10%-100% any value in between.
  • the system pH gradually decreases; during the fourth reaction, the system pH is higher than the third reaction;
  • the pH of the system is in the range of 10-12;
  • the pH of the system is 0.10-0.30 higher than that during the third reaction.
  • the pH of the system is higher than 0.1, 0.2, 0.3 or any value between 0.10-0.30 during the third reaction.
  • the second and third steps grow rapidly in a short period of time.
  • the porosity and layered average thickness of the internal part are based on the reaction time and pH value of each step above, and the raw material mixed metal salt solution to determine the flow rate.
  • the concentration of the nickel-cobalt-manganese ternary mixed solution is 90-130g/L;
  • the concentration of the nickel-cobalt-manganese ternary mixed solution can be any of 90g/L, 100g/L, 110g/L, 120g/L, 125g/L, 130g/L or 90-130g/L. a value;
  • the complexing agent includes one or more of ammonia water, EDTA, ethylenediamine, sodium citrate, and urea;
  • the complexing agent is ammonia water with a mass fraction of 15%-35%;
  • the mass fraction of ammonia water can be 15%, 20%, 25%, 30%, 35% or any value between 15%-35%;
  • the concentration of ammonia in the system is 2.5g/L-6.5g/L L;
  • the concentration of ammonia in the system can be 2.5g/L, 3.0g/L, 3.5g /L, 4.0g/L, 4.5g/L, 5.0g/L, 5.5g/L, 6.0g/L, 6.5g/L or any value between 2.5g/L-6.5g/L;
  • the concentration of ammonia water in the system is higher than the concentration of ammonia water in the second reaction process by 1.0-3.0g/L;
  • the concentration of ammonia water in the system is higher than the concentration of ammonia water in the second reaction process by 1.0g/L, 1.5g/L, 2.0g/L, 2.5g /L, 3.0g/L or any value between 1.0-3.0g/L;
  • the pH regulator includes one or more of sodium hydroxide, potassium hydroxide, sodium bicarbonate, and soda ash;
  • the pH regulator is an aqueous sodium hydroxide solution with a mass fraction of 25%-50%.
  • the mass fraction of the aqueous sodium hydroxide solution may be 25%, 30%, 35%, 40%, 45%, 50% or any value between 25% and 50%.
  • the present application also provides a ternary positive electrode material, which includes layer A, layer B, layer C, and layer D sequentially from the inside to the outside, and the porosity of the layer A, the layer B, and the layer C increases sequentially,
  • the D layer has minimal or no porosity
  • the ternary cathode material is obtained by firing the precursor of the ternary cathode material.
  • the ternary cathode material is obtained by firing the lithium source compound and the above-mentioned precursor of the ternary cathode material as raw materials.
  • the present application also provides a positive electrode of a lithium ion battery, including the ternary positive electrode material.
  • the present application also provides a lithium ion battery, including the positive electrode of the lithium ion battery.
  • the present application also provides an electrical device, including the lithium-ion battery.
  • a positive electrode material active material with four internal porous and dense shell structures (core, two intermediate layers, and shell) is prepared, and the high-nickel ternary precursor material is synthesized with the chemical formula Ni 0.85 Co 0.10 Mn 0.05 (OH) 2 .
  • the preparation method is as follows:
  • NiSO 4 ⁇ 6H 2 O nickel sulfate
  • CoSO 4 ⁇ 7H 2 O cobalt sulfate
  • MnSO 4 ⁇ H 2 O manganese sulfate
  • the metal raw materials are made into a ternary mixed metal salt solution with a concentration of 100g/L according to the molar ratio of nickel, cobalt and manganese in a molar ratio of 0.85:0.10:0.05;
  • the first step, co-precipitation core making A add 5.0m 3 pure water to the 1# reactor as the bottom liquid, add ammonia water and liquid caustic soda (sodium hydroxide aqueous solution) to adjust the ammonia concentration and pH, and adjust the ammonia concentration of the system to 4.0g /L, the pH is 11.90; the reaction temperature is increased to 60°C, the stirring speed is controlled at 220r/min, and when the conditions are met, nickel-cobalt-manganese ternary metal mixed solution, liquid caustic soda, and ammonia water are simultaneously introduced for co-precipitation reaction.
  • ammonia water and liquid caustic soda sodium hydroxide aqueous solution
  • the ternary metal flow rate increases in steps, starting with a ternary metal flow rate of 100L/h and ending with a ternary metal flow rate of 500L/h.
  • the endpoint pH was adjusted to 11.20.
  • the concentrator is turned on, the slurry is circulated, and the mother liquor is discharged outside.
  • the slurry particle size D50 reaches 2.0-3.0 ⁇ m, the feeding is stopped.
  • the second step, co-precipitation to form a porous second intermediate layer structure B transfer the quantitative slurry of the first step 1.8m 3 into the 2# reactor, add pure water to 5.0m 3 , and control the stirring speed at 220r/ min, add ammonia water and liquid caustic soda, adjust the ammonia concentration and pH value, the ammonia concentration of the system is 4.0g/L, the pH is 11.00, the temperature rises to 60°C, and the ternary metal mixed solution, ammonia solution, and sodium hydroxide solution are introduced at the same time.
  • the flow rate of ternary metal increases stepwise, the flow rate of ternary metal at the beginning is 200L/h, and the flow rate of ternary metal at the end is 450L/h.
  • the concentrator is turned on, the slurry is circulated, and the mother liquor is discharged outside.
  • the slurry particle size D50 reaches 3.0-5.0 ⁇ m, the feeding is stopped. Dehydrate to obtain a dry base.
  • the third step is to form the third porous middle layer C: add 5.5m3 of pure water to the 3# reactor, quantitatively input 75kg of dehydrated dry base material in the second step, and add ammonia water and Liquid caustic soda, adjust the ammonia concentration and pH value, adjust the ammonia concentration of the system to 5.5g/L, raise the temperature to 60°C, and then simultaneously pass through the ternary mixed solution, ammonia solution, and sodium hydroxide solution for coprecipitation reaction; among them, the ternary The metal flow rate increases in steps, starting with a ternary metal flow rate of 200L/h and ending with a ternary metal flow rate of 520L/h. Begin pH control at 10.50.
  • the fourth step forming a dense shell D: On the basis of the reaction conditions of the third step, adjust the stirring speed at the end point to 60r/min, control the pH at the end point to 10.65, drop the stirring, and increase the pH.
  • the fourth step reaction reduces the stirring intensity, reduces the supersaturation of the solution, and is conducive to the growth on the interface of the crystal, and increases the system pH in the fourth reaction process, which is conducive to the stability of the crystal particle strength, and then forms a dense shell structure of the crystal plane.
  • the concentrator When the reaction kettle reaches a certain liquid level, the concentrator is turned on, the slurry is circulated, and the mother liquor is discharged outside. When the slurry particle size D50 reaches 13.0-14.0 ⁇ m, the feeding is stopped.
  • Post-treatment Wash the material after stopping the reaction with an appropriate amount of dilute alkali and pure water.
  • the Na and S contents of the washed material are less than 400ppm and 3000ppm respectively; the washed solid particle material is dried at 100°C for 24 hours, and then 400-mesh sieve, packed and sealed. That is, a positive electrode material active material with a four-layer inner porous and dense shell structure is obtained, which is a high-nickel ternary precursor material.
  • a positive electrode material active material with four internal porous and dense shell structures (core, two intermediate layers, and shell) is prepared, and the high-nickel ternary precursor material is synthesized with the chemical formula Ni 0.80 Co 0.10 Mn 0.10 (OH) 2 .
  • the preparation method is as follows:
  • NiSO 4 ⁇ 6H 2 O nickel sulfate
  • CoSO 4 ⁇ 7H 2 O cobalt sulfate
  • MnSO 4 ⁇ H 2 O manganese sulfate
  • the metal raw materials are made into a ternary mixed metal salt solution with a concentration of 105g/L according to the molar ratio of nickel, cobalt and manganese in a molar ratio of 0.80:0.10:0.10;
  • the first step, co-precipitation core A add 5.0m 3 pure water to the 1# reactor as the bottom liquid, add ammonia water and liquid caustic soda to adjust the ammonia concentration and pH, adjust the ammonia concentration of the system to 4.0g/L, and the pH to 11.90
  • the reaction temperature rises to 60°C, and the stirring speed is controlled at 220r/min.
  • nickel-cobalt-manganese ternary metal mixed solution, liquid caustic soda, and ammonia water are simultaneously introduced to carry out co-precipitation reaction.
  • the ternary metal flow rate increases in steps, starting with a ternary metal flow rate of 100L/h and ending with a ternary metal flow rate of 500L/h.
  • the endpoint pH was adjusted to 11.20.
  • the concentrator is turned on, the slurry is circulated, and the mother liquor is discharged outside.
  • the slurry particle size D50 reaches 2.0-3.0 ⁇ m, the feeding is stopped.
  • the second step, co-precipitation to form a porous second intermediate layer structure B transfer the quantitative slurry of the first step 1.8m 3 into the 2# reactor, add pure water to 5.0m 3 , and control the stirring speed at 220r/ min, add ammonia water and liquid caustic soda, adjust the ammonia concentration and pH value, the ammonia concentration of the system is 4.0g/L, the pH is 11.00, the temperature rises to 60°C, and at the same time, the ternary metal mixed solution, ammonia solution and sodium hydroxide solution are introduced to carry out Co-precipitation reaction; the flow rate of ternary metal increases stepwise, the flow rate of ternary metal at the beginning is 200L/h, and the flow rate of ternary metal at the end is 480L/h.
  • the concentrator When the reaction kettle reaches a certain liquid level, the concentrator is turned on, the slurry is circulated, and the mother liquor is discharged outside. When the slurry particle size D50 reaches 3.0-5.0 ⁇ m, the feeding is stopped. Dehydrate to obtain a dry base.
  • the third step is to form the third porous middle layer C and the dense outer shell D: add 5.5m 3 of pure water to the 3# reactor, quantitatively input 80kg of dehydrated dry base material in the second step, and stir at 180r/min , add ammonia water and liquid caustic soda, adjust the ammonia concentration and pH value, adjust the ammonia concentration of the system to 5.5g/L, raise the temperature to 60°C, and then simultaneously feed the ternary mixed solution, ammonia solution, and sodium hydroxide solution for coprecipitation reaction;
  • the ternary metal flow rate increases in steps, starting with a ternary metal flow rate of 200L/h and ending with a ternary metal flow rate of 550L/h. Begin pH control at 10.55.
  • the fourth step forming a dense shell D: On the basis of the reaction conditions of the third step, adjust the stirring speed of the reaction at the end stage to 60r/min, control the pH at the end stage to 10.70, drop the stirring, and increase the pH.
  • the fourth step reaction reduces the stirring intensity, reduces the supersaturation of the solution, and is conducive to the growth of the crystal interface, and increases the pH of the system during the fourth reaction process, which is conducive to the stability of the crystal particle strength, and then forms a dense shell structure of the crystal plane.
  • the concentrator When the reaction kettle reaches a certain liquid level, the concentrator is turned on, the slurry is circulated, and the mother liquor is discharged outside. When the slurry particle size D50 reaches 13.0-14.0 ⁇ m, the feeding is stopped.
  • Post-treatment Wash the material after stopping the reaction with an appropriate amount of dilute alkali and pure water.
  • the Na and S contents of the washed material are less than 400ppm and 3000ppm respectively; the washed solid particle material is dried at 100°C for 24 hours, and then 400-mesh sieve, packed and sealed. That is, a positive electrode material active material with a four-layer inner porous and dense shell structure is obtained, which is a high-nickel ternary precursor material.
  • a high-nickel ternary precursor material for positive electrode material active material with four internal porous and dense shell structures was prepared, and the synthetic chemical formula was Ni 0.90 Co 0.05 Mn 0.05 (OH) 2 .
  • the preparation method is as follows:
  • NiSO 4 ⁇ 6H 2 O nickel sulfate
  • CoSO 4 ⁇ 7H 2 O cobalt sulfate
  • MnSO 4 ⁇ H 2 O manganese sulfate
  • the metal raw materials are made into a ternary mixed metal salt solution with a concentration of 110g/L according to the molar ratio of nickel, cobalt and manganese in a molar ratio of 0.90:0.05:0.05;
  • the first step, co-precipitation core A add 5.0m 3 pure water to the 1# reactor as the bottom liquid, add ammonia water and liquid caustic soda to adjust the ammonia concentration and pH, adjust the ammonia concentration of the system to 4.0g/L, and the pH to 11.90
  • the reaction temperature rises to 60°C, and the stirring speed is controlled at 220r/min.
  • nickel-cobalt-manganese ternary metal mixed solution, liquid caustic soda, and ammonia water are simultaneously introduced to carry out co-precipitation reaction.
  • the ternary metal flow rate increases in steps, starting with a ternary metal flow rate of 100L/h and ending with a ternary metal flow rate of 500L/h.
  • the endpoint pH was adjusted to 11.20.
  • the concentrator is turned on, the slurry is circulated, and the mother liquor is discharged outside.
  • the slurry particle size D50 reaches 2.0-3.0 ⁇ m, the feeding is stopped.
  • the second step, co-precipitation to form a porous second intermediate layer structure B transfer the quantitative slurry of the first step 1.8m 3 into the 2# reactor, add pure water to 5.0m 3 , and control the stirring speed at 220r/ min, add ammonia water and liquid caustic soda, adjust the ammonia concentration and pH value, the ammonia concentration of the system is 4.0g/L, the pH is 11.00, the temperature rises to 60°C, and at the same time, the ternary metal mixed solution, ammonia solution and sodium hydroxide solution are introduced to carry out Co-precipitation reaction; the flow rate of ternary metal increases stepwise, the flow rate of ternary metal at the beginning is 200L/h, and the flow rate of ternary metal at the end is 500L/h.
  • the concentrator When the reaction kettle reaches a certain liquid level, the concentrator is turned on, the slurry is circulated, and the mother liquor is discharged outside. When the slurry particle size D50 reaches 3.0-5.0 ⁇ m, the feeding is stopped. Dehydrate to obtain a dry base.
  • the third step is to form the third porous middle layer C and the dense outer shell D: add 5.5m 3 of pure water to the 3# reactor, quantitatively input 85kg of dehydrated dry base material in the second step, and stir at 180r/min , add ammonia water and liquid caustic soda, adjust the ammonia concentration and pH value, adjust the ammonia concentration of the system to 5.5g/L, raise the temperature to 60°C, and then simultaneously feed the ternary mixed solution, ammonia solution, and sodium hydroxide solution for coprecipitation reaction; Among them, the flow rate of ternary metal increases stepwise, the flow rate of ternary metal at the beginning is 200L/h, and the flow rate of ternary metal at the end is 600L/h. In the initial stage, the pH was controlled at 10.60.
  • the fourth step forming a dense shell D: On the basis of the reaction conditions of the third step, adjust the stirring speed of the reaction at the end stage to 60r/min, control the pH at the end stage to 10.75, drop the stirring, and increase the pH.
  • the fourth step reaction reduces the stirring intensity, reduces the supersaturation of the solution, and is conducive to the growth of the crystal interface, and increases the pH of the system during the fourth reaction process, which is conducive to the stability of the crystal particle strength, and then forms a dense shell structure of the crystal plane.
  • the concentrator When the reaction kettle reaches a certain liquid level, the concentrator is turned on, the slurry is circulated, and the mother liquor is discharged outside. When the slurry particle size D50 reaches 13.0-14.0 ⁇ m, the feeding is stopped.
  • Post-treatment Wash the material after stopping the reaction with an appropriate amount of dilute alkali and pure water.
  • the Na and S contents of the washed material are less than 400ppm and 3000ppm respectively; the washed solid particle material is dried at 100°C for 24 hours, and then 400-mesh sieve, packed and sealed. That is, a positive electrode material active material with a four-layer inner porous and dense shell structure is obtained, which is a high-nickel ternary precursor material.
  • a positive electrode material active material with a four-layer internal porous and dense shell structure (core, two intermediate layers, and shell) is prepared, and the high-nickel ternary precursor material is synthesized with the chemical formula Ni 0.93 Co 0.04 Mn 0.03 (OH) 2 .
  • the preparation method is as follows:
  • NiSO 4 ⁇ 6H 2 O nickel sulfate
  • CoSO 4 ⁇ 7H 2 O cobalt sulfate
  • MnSO 4 ⁇ H 2 O manganese sulfate
  • the metal raw materials are made into a ternary mixed metal salt solution with a concentration of 125g/L according to the molar ratio of nickel, cobalt and manganese in a molar ratio of 0.93:0.04:0.03;
  • the first step, co-precipitation core A add 5.0m 3 pure water to the 1# reactor as the bottom liquid, add ammonia water and liquid caustic soda to adjust the ammonia concentration and pH, adjust the ammonia concentration of the system to 4.0g/L, and the pH to 11.90
  • the reaction temperature rises to 60°C, and the stirring speed is controlled at 220r/min.
  • nickel-cobalt-manganese ternary metal mixed solution, liquid caustic soda, and ammonia water are simultaneously introduced to carry out co-precipitation reaction.
  • the ternary metal flow rate increases in steps, starting with a ternary metal flow rate of 100L/h and ending with a ternary metal flow rate of 500L/h.
  • the endpoint pH was adjusted to 11.20.
  • the concentrator is turned on, the slurry is circulated, and the mother liquor is discharged outside.
  • the slurry particle size D50 reaches 2.0-3.0 ⁇ m, the feeding is stopped.
  • the second step, co-precipitation to form a porous second intermediate layer structure B transfer the quantitative slurry of the first step 1.8m 3 into the 2# reactor, add pure water to 5.0m 3 , and control the stirring speed at 220r/ min, add ammonia water and liquid caustic soda, adjust the ammonia concentration and pH value, the ammonia concentration of the system is 4.0g/L, the pH is 11.00, the temperature rises to 60°C, and at the same time, the ternary metal mixed solution, ammonia solution and sodium hydroxide solution are introduced to carry out Co-precipitation reaction; among them, the flow rate of ternary metal increases stepwise, the flow rate of ternary metal at the beginning is 200L/h, and the flow rate of ternary metal at the end is 550L/h.
  • the concentrator When the reaction kettle reaches a certain liquid level, the concentrator is turned on, the slurry is circulated, and the mother liquor is discharged outside. When the slurry particle size D50 reaches 3.0-5.0 ⁇ m, the feeding is stopped. Dehydrate to obtain a dry base.
  • the third step is to form the third porous middle layer C and the dense outer shell D: add 5.5m 3 of pure water to the 3# reactor, and quantitatively put 90kg of dehydrated dry base material in the second step, under the condition of 180r/min stirring , add ammonia water and liquid caustic soda, adjust the ammonia concentration and pH value, adjust the ammonia concentration of the system to 5.5g/L, raise the temperature to 60°C, and then simultaneously feed the ternary mixed solution, ammonia solution, and sodium hydroxide solution for coprecipitation reaction; Among them, the ternary metal flow rate increases in steps, starting with a ternary metal flow rate of 200L/h, and ending with a ternary metal flow rate of 650L/h. In the initial stage, the pH was controlled at 10.65.
  • the fourth step forming a dense shell D: On the basis of the reaction conditions of the third step, adjust the reaction stirring speed at the end stage to 60r/min, control the pH at the end stage to 10.85, drop the stirring, and increase the pH.
  • the fourth step reaction reduces the stirring intensity, reduces the supersaturation of the solution, and is conducive to the growth of the crystal interface, and increases the pH of the system during the fourth reaction process, which is conducive to the stability of the crystal particle strength, and then forms a dense shell structure of the crystal plane.
  • the concentrator When the reaction kettle reaches a certain liquid level, the concentrator is turned on, the slurry is circulated, and the mother liquor is discharged outside. When the slurry particle size D50 reaches 13.0-14.0 ⁇ m, the feeding is stopped.
  • Post-treatment After the reaction is stopped, the material is washed with an appropriate amount of dilute alkali and pure water.
  • the Na and S contents of the washed material are less than 400ppm and 3000ppm respectively; Mesh sieve, packaged and sealed. That is, a positive electrode material active material with a four-layer inner porous and dense shell structure is obtained, which is a high-nickel ternary precursor material.
  • a high-nickel ternary precursor material with a three-layer inner dense and less porous shell structure was prepared, and the synthetic formula was Ni 0.85 Co 0.10 Mn 0.05 (OH) 2 .
  • the preparation method is as follows:
  • NiSO 4 ⁇ 6H 2 O nickel sulfate
  • CoSO 4 ⁇ 7H 2 O cobalt sulfate
  • MnSO 4 ⁇ H 2 O manganese sulfate
  • the metal raw materials are made into a ternary mixed metal salt solution with a concentration of 110g/L according to the molar ratio of nickel, cobalt and manganese in a molar ratio of 0.85:0.10:0.05;
  • the first step add 5.0m 3 pure water to the 1# reactor as the bottom liquid, add ammonia water and liquid caustic soda to adjust the ammonia concentration and pH, adjust the ammonia concentration of the system to 4.0g/L, and the pH to 11.90; the reaction temperature rises to 60 °C, the stirring speed is controlled at 220r/min, and when the conditions are met, the nickel-cobalt-manganese ternary metal mixed solution, liquid caustic soda, and ammonia water are simultaneously passed through for co-precipitation reaction.
  • the ternary metal flow rate increases in steps, starting with a ternary metal flow rate of 100L/h and ending with a ternary metal flow rate of 500L/h.
  • the endpoint pH was adjusted to 11.20.
  • the concentrator is turned on, the slurry is circulated, and the mother liquor is discharged outside.
  • the slurry particle size D50 reaches 2.0-3.0 ⁇ m, the feeding is stopped.
  • the second step transfer the quantitative 1.8m 3 of the slurry in the first step into the 2# reactor, add pure water to 5.0m 3 , control the stirring speed at 220r/min, add ammonia water and liquid caustic soda, and adjust the ammonia concentration
  • the pH value the ammonia concentration of the system is 4.0g/L
  • the pH is 11.00
  • the ternary metal mixed solution, ammonia solution, and sodium hydroxide solution are introduced to carry out coprecipitation reaction; among them, the ternary metal flow rate is divided into Stepwise growth, the flow rate of ternary metal at the beginning is 200L/h, and the flow rate of ternary metal at the end is 500L/h.
  • the concentrator When the reaction kettle reaches a certain liquid level, the concentrator is turned on, the slurry is circulated, and the mother liquor is discharged outside. When the slurry particle size D50 reaches 3.0-5.0 ⁇ m, the feeding is stopped. Dehydrate to obtain a dry base.
  • the third step Add 5.5m 3 of pure water to the 3# reactor, quantitatively put 75kg of the dehydrated dry base material in the second step, and add ammonia water and liquid caustic soda under the stirring condition of 180r/min to adjust the ammonia concentration and pH value , the ammonia concentration of the debugging system is 7.5g/L, the temperature rises to 60°C, and then the ternary mixed solution, ammonia solution, and sodium hydroxide solution are simultaneously introduced to carry out coprecipitation reaction; among them, the ternary metal flow increases in steps, and the three The primary metal flow rate is 200L/h, and the terminal ternary metal flow rate is 500L/h.
  • the pH is controlled at 10.45 at the beginning stage and 10.60 at the end stage; the reaction stirring speed is gradually decreased to 60r/min at the end stage.
  • the concentrator is turned on, the slurry is circulated, and the mother liquor is discharged outside.
  • the slurry particle size D50 reaches 13.0-14.0 ⁇ m, the feeding is stopped.
  • Post-treatment Wash the material after stopping the reaction with an appropriate amount of dilute alkali and pure water.
  • the Na and S contents of the washed material are less than 400ppm and 3000ppm respectively; dry the washed solid particle material at 100°C for 24 hours, Sieve through a 400-mesh sieve, and pack and seal.
  • the steps of the comparative example 1 and the example, the flow rate of the ternary metal is basically the same, and the pH of the end point and the concentration of ammonia water can be adjusted in the comparative example to obtain a ternary precursor material with a three-layer internal dense structure.
  • a high-nickel ternary precursor material of the positive electrode material active material with a two-layer inner dense less-porous shell structure (core and shell) was prepared, and the synthetic chemical formula was Ni 0.80 Co 0.15 Mn 0.05 (OH) 2 .
  • the preparation method is as follows:
  • NiSO 4 ⁇ 6H 2 O nickel sulfate
  • CoSO 4 ⁇ 7H 2 O cobalt sulfate
  • MnSO 4 ⁇ H 2 O manganese sulfate
  • the metal raw materials are made into a ternary mixed metal salt solution with a concentration of 110g/L according to the molar ratio of nickel, cobalt and manganese in a molar ratio of 0.80:0.15:0.05;
  • the first step add 5.0m 3 pure water to the 1# reactor as the bottom liquid, add ammonia water and liquid caustic soda to adjust the ammonia concentration and pH, adjust the ammonia concentration of the system to 4.0g/L, and the pH to 11.90; the reaction temperature rises to 60 °C, the stirring speed is controlled at 220r/min, and when the conditions are met, the nickel-cobalt-manganese ternary metal mixed solution, liquid caustic soda, and ammonia water are simultaneously passed through for co-precipitation reaction.
  • the ternary metal flow rate increases in steps, starting with a ternary metal flow rate of 100L/h and ending with a ternary metal flow rate of 500L/h.
  • the endpoint pH was adjusted to 11.20.
  • the concentrator is turned on, the slurry is circulated, and the mother liquor is discharged outside.
  • the slurry particle size D50 reaches 2.0-3.0 ⁇ m, the feeding is stopped.
  • the second step transfer the quantitative 1.8m 3 of the slurry in the first step into the 2# reactor, add pure water to 5.0m 3 , control the stirring speed at 220r/min, add ammonia water and liquid caustic soda, and adjust the ammonia concentration
  • the pH value the ammonia concentration of the system is 4.0g/L
  • the pH is 11.00
  • the ternary metal mixed solution, ammonia solution, and sodium hydroxide solution are introduced to carry out coprecipitation reaction; among them, the ternary metal flow rate is divided into Stepwise growth, the flow rate of ternary metal at the beginning is 200L/h, and the flow rate of ternary metal at the end is 500L/h.
  • the concentrator When the reaction kettle reaches a certain liquid level, the concentrator is turned on, the slurry is circulated, and the mother liquor is discharged outside. When the slurry particle size D50 reaches 3.0-5.0 ⁇ m, the feeding is stopped. Dehydrate to obtain a dry base.
  • the third step Add 5.0m 3 of pure water to the 3# reactor, quantitatively put 75kg of dehydrated dry base material in the second step, and add ammonia water and liquid caustic soda under the stirring condition of 180r/min to adjust the ammonia concentration and pH value , the ammonia concentration of the debugging system was 8.0g/L, the temperature rose to 60°C, and then the ternary mixed solution, ammonia solution, and sodium hydroxide solution were simultaneously introduced to carry out coprecipitation reaction; among them, the ternary metal flow rate increased in steps, and the three-way metal flow rate increased in steps.
  • the primary metal flow rate is 200L/h
  • the terminal ternary metal flow rate is 500L/h.
  • the pH is controlled at 10.40 in the initial stage, and the pH is controlled at 10.55 in the final stage, and the reaction stirring speed is gradually reduced to 60r/min in the final stage.
  • the concentrator is turned on, the slurry is circulated, and the mother liquor is discharged outside.
  • the slurry particle size D50 reaches 13.0-14.0 ⁇ m, the feeding is stopped.
  • Post-treatment Wash the material after stopping the reaction with an appropriate amount of dilute alkali and pure water.
  • the Na and S contents of the washed material are less than 400ppm and 3000ppm respectively; the washed solid particle material is dried at 100°C for 24 hours, and then 400-mesh sieve, packed and sealed.
  • the steps of the comparative example 2 and the example, the ternary metal flow rate is basically the same; the comparative example adjusts the end point pH and the concentration of ammonia water to obtain a ternary precursor material with a dense and less porous structure inside the three layers.
  • a positive electrode material active material with a dense inner structure (core and shell) and a high-nickel ternary precursor material were prepared through two steps, and the synthetic formula was Ni 0.85 Co 0.10 Mn 0.05 (OH) 2 .
  • the preparation method is as follows:
  • NiSO 4 ⁇ 6H 2 O nickel sulfate
  • CoSO 4 ⁇ 7H 2 O cobalt sulfate
  • MnSO 4 ⁇ H 2 O manganese sulfate
  • the metal raw materials are made into a ternary mixed metal salt solution with a concentration of 110g/L according to the molar ratio of nickel, cobalt and manganese in a molar ratio of 0.85:0.10:0.05;
  • the first step add 8.0m 3 pure water to the 1# reactor as the bottom liquid, add ammonia water and liquid caustic soda to adjust the ammonia concentration and pH, adjust the ammonia concentration of the system to 4.0g/L, and the pH to 11.90; the reaction temperature rises to 60 °C, the stirring speed is controlled at 220r/min, and when the conditions are met, the nickel-cobalt-manganese ternary metal mixed solution, liquid caustic soda, and ammonia water are simultaneously passed through for co-precipitation reaction.
  • the ternary metal flow increases in steps, starting with ternary metal flow of 100L/h, ending ternary metal flow of 500L/h, and ending pH is adjusted to 11.20.
  • the concentrator When the reaction kettle reaches a certain liquid level, the concentrator is turned on, the slurry is circulated, and the mother liquor is discharged outside. When the slurry particle size D50 reaches 3.0-5.0 ⁇ m, the feeding is stopped.
  • the second step transfer 80kg of the dehydrated dry base material of the first step into the 2# reactor, add pure water to 5.0m 3 , control the stirring speed at 220r/min, add ammonia water and liquid caustic soda, adjust the ammonia Concentration and pH value, the ammonia concentration of the system is 6.0g/L, the pH is 10.80, the temperature rises to 60°C, and at the same time, the ternary metal mixed solution, ammonia solution, and sodium hydroxide solution are introduced for co-precipitation reaction; among them, the ternary metal flow Stepwise growth, the initial ternary metal flow rate is 200L/h, and the final ternary metal flow rate is 600L/h; the stirring speed gradually decreases during the reaction process, and the final speed is 100r/min; the pH of the reaction system gradually increases, and the final pH is 11.20.
  • the concentrator When the reaction kettle reaches a certain liquid level, the concentrator is turned on, the slurry is circulated, and the mother liquor is discharged outside. When the slurry particle size D50 reaches 12.0-14.0 ⁇ m, the feeding is stopped.
  • Comparative Example 3 went through two steps, the pH of the second step system gradually increased, and the end point pH reached 11.20, which was basically the same as the end point pH of the first step, and a ternary precursor material with an internal dense structure (core, shell) was obtained; The dense ternary precursor material of the four-layer inner porous shell in the examples could not be obtained.
  • a low-nickel (5 series) positive electrode material active material with a dense, non-porous and layer-free internal structure and a high-nickel ternary precursor material were prepared, and the synthetic formula was Ni 0.50 Co 0.20 Mn 0.30 (OH) 2 .
  • the preparation method is as follows:
  • NiSO 4 ⁇ 6H 2 O nickel sulfate
  • CoSO 4 ⁇ 7H 2 O cobalt sulfate
  • MnSO 4 ⁇ H 2 O manganese sulfate
  • the metal raw materials are made into a ternary mixed metal salt solution with a concentration of 110g/L according to the molar ratio of nickel, cobalt and manganese in a molar ratio of 0.50:0.20:0.30;
  • the first step add 8.0m 3 pure water to the 1# reactor as the bottom liquid, add ammonia water and liquid caustic soda to adjust the ammonia concentration and pH, adjust the ammonia concentration of the system to 4.0g/L, and the pH to 10.95; the reaction temperature rises to 60 °C, the stirring speed is controlled at 220r/min, and when the conditions are met, the nickel-cobalt-manganese ternary metal mixed solution, liquid caustic soda, and ammonia water are simultaneously passed through for co-precipitation reaction.
  • the flow rate of ternary metal is 500L/h
  • the flow rate of liquid caustic soda is 185L/H
  • the flow rate of ammonia water is 17L/H.
  • the second step Quantitatively transfer the 7.5m3 slurry into the first step in the 2# reactor, add ammonia water and liquid caustic soda to adjust the ammonia concentration and pH, adjust the system ammonia concentration to 5.0g/L, and the pH is 10.80; the reaction temperature rises To 60°C, the stirring speed is controlled at 200r/min, and when the conditions are met, the nickel-cobalt-manganese ternary metal mixed solution, liquid caustic soda, and ammonia water are simultaneously passed through for co-precipitation reaction.
  • the flow rate of the ternary metal is fixed, the stirring speed is kept constant, and the pH is kept constant.
  • the low-nickel series products of Comparative Example 4 passed two steps, stirred at a high speed, kept the flow rate and pH unchanged, and obtained a dense, non-porous and non-hierarchical structure inside; the four-layer structure in the Examples could not be obtained.
  • Figure 2 is a cross-sectional SEM photo of the ternary positive electrode material precursor obtained in Example 1;
  • Figure 3 is a high-magnification electron microscope photo of the ternary positive electrode material precursor obtained in Example 1;
  • Figure 4 is the three-dimensional positive electrode material precursor obtained in Example 1 Partial high-magnification electron micrograph of the precursor of the positive electrode material;
  • Fig. 5 is a high-power electron microscope photo of the precursor of the ternary positive electrode material obtained in Example 2;
  • FIG. 6 is a local high-magnification electron microscope photo of the precursor of the ternary positive electrode material obtained in Example 2;
  • Figure 7 is the XRD spectrum of the ternary positive electrode material precursor obtained in Examples 1, 2, 3, and 4 (calculated on the right, from top right to bottom in order: Example 3, Example 4, Example 2 and Example 1);
  • Figure 8 is a cross-sectional SEM photo of the ternary positive electrode material precursor obtained in Example 2;
  • Figure 9 is a cross-sectional SEM photo of the ternary positive electrode material precursor obtained in Example 3;
  • Figure 10 is a ternary positive electrode material obtained in Example 4 The cross-sectional SEM photograph of the precursor;
  • Figure 11 is the cross-sectional SEM photograph of the ternary positive electrode material precursor obtained in Comparative Example 1;
  • Figure 12 is the high-magnification electron microscope photograph of the ternary positive electrode material precursor obtained in Comparative Example 1;
  • Figure 13 is a comparative example 1
  • the ternary precursor obtained in the embodiment has a four-layer structure including a core, two intermediate layers and a shell, and presents a four-layer inner porous and dense less porous shell structure .
  • the precursor obtained in Comparative Example 1 includes a three-layer structure of a core, an intermediate layer and a shell, and the inner layer to the outer layer are dense and less porous.
  • the precursor obtained in Comparative Example 2 and Comparative Example 3 includes a core and shell two-layer structure, and the inner layer to the outer layer are dense and less porous.
  • the electrochemical performance test is carried out by button-type semi-electrode: the above-mentioned positive electrode material, conductive carbon black, and binder PVDF (polyvinylidene fluoride) are adjusted into a slurry according to 8:1:1, and coated on aluminum foil to make a positive electrode sheet, and a negative electrode Lithium sheet is used as the sheet, and 1mol/L LiPF 6 /EC:DMC (volume ratio 1:1) is used as the electrolyte.
  • the battery case, positive and negative electrode sheets, separators, shrapnel, and gaskets are assembled into a button type in a vacuum glove box. Battery.
  • the electrochemical performance test was carried out by blue electric test system.
  • Embodiment FWHM (101/001) ratio is 1.1-1.2
  • embodiment 1 (001/101 ) is 1.1-1.2, it shows that the half peak width of 001 peak is smaller than that of 101 peak, and the intensity of 001 peak is higher than that of 101 peak, which proves that the material of the embodiment grows preferentially at 001 peak, and the crystallinity of the material is stronger and the structure is more stable.
  • Comparative Example 4 is a material with low nickel, high cobalt and high manganese ratio, the unit cell parameter is large, the half-peak width of 001 is smaller, and the peak intensity of 001 is very high. Due to the inconsistent ratio, no comparison is made ; As can be seen from the electrochemical performance table 2, high-nickel products have better electrochemical performance.
  • the high-nickel precursor of the ternary cathode material of the present application has better performance.
  • the precursor material of the ternary cathode material provided by this application has a four-layer structure inside the particles that breaks through the existing dense structure, and the internal structure presents a multi-layer porous and stable structure, which further provides a new direction for the internal hierarchical structure of the ternary precursor particles of the cathode material.
  • any one of the claimed embodiments may be used in any combination.
  • the information disclosed in the background technology section is only intended to deepen the understanding of the general background technology of the application, and should not be regarded as an acknowledgment or any form of suggestion that the information constitutes the prior art known to those skilled in the art.

Landscapes

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

Abstract

本申请提供一种三元正极材料前驱体及其制备方法、三元正极材料、锂离子电池及正极和涉电设备。三元正极材料前驱体,由内至外依次包括核层、第一中间层、第二中间层和壳层,核层、第一中间层、第二中间层的孔隙率依次增大,壳层的孔隙率最小或无孔。其制备方法包括:将包括镍钴锰三元混合溶液、络合剂、pH调节剂在内的原料进行第一反应得到核层;调整反应条件,进行第二反应在核层的表面形成第一中间层;调整反应条件,进行第三反应在第一中间层的表面形成第二中间层;调整反应条件,进行第四反应在第二中间层的表面形成壳层。三元正极材料,由内至外依次包括A层、B层、C层和D层。本申请提供的三元正极材料前驱体,性能优异。

Description

三元正极材料前驱体及其制备方法、三元正极材料、锂离子电池及正极和涉电设备
相关申请的交叉引用
本申请要求于2022年01月27日提交中国专利局的申请号为202210101448.7、名称为“三元正极材料前驱体及其制备方法、三元正极材料、锂离子电池及正极和涉电设备”的中国专利申请的优先权,其全部内容通过引用结合在本申请中。
技术领域
本申请涉及锂离子电池领域,尤其涉及一种三元正极材料前驱体及其制备方法、三元正极材料、锂离子电池及正极和涉电设备。
背景技术
2021年,我国提出二氧化碳排放力争在2030年前达到峰值,努力争取2060年前实现碳中和;然而,世界汽车行业在迅速发展,汽车尾气排放量直接影响碳排放量;因此,绿色新能源汽车作为行业的未来发展方向,新能源汽车以锂电池作为新能源汽车的核心动力,正极前驱体材料作为锂电池的最重要组成部分,一直是技术核心所在。目前市面上最常见的有5系、6系三元前驱体,不过其电容量较低,限制了它在新能源汽车的应用。
各前驱体厂家陆续开发出高镍的前驱体产品,提高电池的容量,延长续航能力;高镍大颗粒前驱体一般采用间歇法合成,具有极窄的粒径分布,可也使得颗粒结构均一性强。
目前在锂电三元前驱体领域里,三元前驱体颗粒内部一般为孔隙少的致密结构,内部分布不均匀;其三元前驱体颗粒所制备的电池,锂离子扩散路径单一,扩散阻力大,倍率性能不足;并且,电池一直存在随着反复充电和放电,颗粒结构强度不稳定会在颗粒单元中易产生了开裂的问题,导致锂二次电池的寿命变短,容量变低,使用过程中安全性能较差。
因此,三元前驱体颗粒的内部结构单一,扩散阻力大,颗粒强度开裂不稳定导致电池的循环性能、倍率性能、安全性能等较差的突出问题成为当前急需攻克的技术难题。
发明内容
本申请的目的在于提供一种三元正极材料前驱体及其制备方法、三元正极材料、锂离子电池及正极和涉电设备,以解决上述问题。
为实现以上目的,本申请采用以下技术方案:
一种三元正极材料前驱体,由内至外依次包括核层、第一中间层、第二中间层和壳层,所述核层、所述第一中间层、所述第二中间层的孔隙率依次增大,所述壳层的孔隙率最小或无孔。
优选地,所述核层的孔隙率为1.40%-7.96%,所述第一中间层的孔隙率为2.10%-8.37%,所述第二中间层的孔隙率为4.57%-16.72%,所述壳层的孔隙率小于等于1%;
优选地,所述核层的孔隙率为2.0%-4.0%,所述第一中间层的孔隙率为3.0%-5.0%,所述第二中间层的孔隙率为7.35%-10.32%,所述壳层的孔隙率小于等于0.5%。
优选地,所述三元正极材料前驱体的各层平均厚度均小于等于3μm;
优选地,所述核层的直径为1.0μm-3.0μm,所述第一中间层的平均厚度为0.2μm-2.0μm,所述第二中间层的平均厚度为1μm-2.5μm,所述壳层的平均厚度为0.5μm-1.5μm。
优选地,所述三元正极材料前驱体内的一次颗粒沿其径向方向、由内至外呈松散交叉针条状分布;
优选地,所述核层整体呈现球形;
优选地,所述壳层内的一次颗粒沿所述三元正极材料前驱体的径向方向呈现针条状;
优选地,所述三元正极材料前驱体的平均粒径为12μm-15μm;
优选地,D95/D50=1.0-1.6;
优选地,所述三元正极材料前驱体的BET为11m 2/g-17m 2/g。
优选地,衍射角2θ为19.2±1°范围的001峰的半峰宽α小于等于0.6;
优选地,所述半峰宽α为0.43-0.53;
优选地,衍射角2θ为38.5±1°范围的101峰的半峰宽β小于等于0.7;
优选地,所述半峰宽β为0.48-0.58;
优选地,所述半峰宽β与所述半峰宽α的比值大于等于1.02,峰强比I(001/101)为1.0-1.2;
优选地,所述半峰宽β与所述半峰宽α的比值为1.02-1.25。
优选地,其化学通式为Ni xCo yMn z(OH) 2,其中0.8≤x≤0.98,0.01≤y<0.18,0.01≤z<0.17,x+y+z=1。
本申请还提供一种所述的三元正极材料前驱体的制备方法,包括:
将包括镍钴锰三元混合溶液、络合剂、pH调节剂在内的原料进行第一反应得到核层;
调整反应条件,进行第二反应在所述核层的表面形成第一中间层;
调整反应条件,进行第三反应在所述第一中间层的表面形成第二中间层;
调整反应条件,进行第四反应在所述第二中间层的表面形成壳层。
优选地,所述第一反应、所述第二反应、所述第三反应、所述第四反应均在搅拌状态下进行,搅拌速度依次降低;
优选地,所述第一反应的搅拌速度为200r/min-240r/min,所述第二反应的搅拌速度为180r/min-230r/min,所述第三反应的搅拌速度为100r/min-200r/min,所述第四反应的搅拌速度为40r/min-100r/min。
优选地,所述第一反应、所述第二反应、所述第三反应、所述第四反应的过程中,所述镍钴锰三元混合溶液的加入量依次增大;
优选地,所述第一反应的过程中,所述镍钴锰三元混合溶液的加入量为80L/h-550L/h;所述第二反应的过程中,所述镍钴锰三元混合溶液的加入量为150L/h-650L/h;所述第三反应、所述第四反应的过程中,所述镍钴锰三元混合溶液的加入量为150L/h-750L/h;
优选地,所述第一反应、所述第二反应、所述第三反应、所述第四反应的过程中,每个反应过程中,所述镍钴锰三元混合溶液的加入量呈阶梯式增大;
优选地,所述阶梯式增大的比例为10%-100%。
优选地,所述第一反应、所述第二反应、所述第三反应的过程中,体系pH逐步降低;所述第四反应的过程中,体系pH高于所述第三反应;
优选地,所述第一反应、所述第二反应、所述第三反应、所述第四反应的过程中,体系pH的范围为10-12;
优选地,所述第四反应的过程中,体系pH高于第三反应过程中0.10-0.30。
优选地,所述镍钴锰三元混合溶液的浓度为90-130g/L;
优选地,所述络合剂包括氨水、EDTA、乙二胺、柠檬酸钠、尿素中的一种或多种;
优选地,所述络合剂为质量分数为15%-35%的氨水;
优选地,所述第一反应、所述第二反应、所述第三反应、所述第四反应中,体系中所述氨水的浓度为2.5g/L-6.5g/L;
优选地,第三反应、第四反应的过程中,体系中氨水的浓度高于所述第二反应过程中的氨水的浓度1.0-3.0g/l;
优选地,所述pH调节剂包括氢氧化钠、氢氧化钾、碳酸氢钠、纯碱中的一种或多种;
优选地,所述pH调节剂为质量分数为25%-50%的氢氧化钠水溶液。
本申请还提供一种三元正极材料,由内至外依次包括A层、B层、C层和D层,所述A层、所述B层、所述C层的孔隙率依次增大,所述D层的孔隙率最小或无孔;
优选地,所述三元正极材料使用所述的三元正极材料前驱体烧制得到。
本申请还提供一种锂离子电池正极,包括所述的三元正极材料。
本申请还提供一种锂离子电池,包括所述的锂离子电池正极。
本申请还提供一种涉电设备,包括所述的锂离子电池。
与现有技术相比,本申请的有益效果包括:
本申请提供的三元正极材料前驱体,相比目前内部致密结构的三元前驱体,该三元前驱体由内至外依次包括核层、第一中间层、第二中间层和壳层,所述核层、所述第一中间层、所述第二中间层的孔隙率依次增大,所述壳层的孔隙率最小或无孔;内部三层孔隙率逐步增大,这种结构形成相对较多扩散路径,锂离子传输通道变多,降低了锂离子的扩散阻力,有效提高锂离子的扩散速率,从而提高充放电性能、倍率性能、循环性能;壳层孔隙率最小或无孔,为致密少孔外壳结构,从而表现出内松外紧的形态,可承受由充电和放电产生的应力,致密少孔外壳可以保护结构稳定性;并且,正极材料三元前驱体内部结构满足结构的孔隙率一定范围以及壳层少孔致密结构,提升颗粒强度,在电池充放电过程中,颗粒不易开裂,从而增加使用循环保持率和寿命,电池性能优异。
本申请提供的三元正极材料前驱体的制备方法,通过第一反应、第二反应、第三反应与第四反应能够稳定的用溶液共沉淀法制备得到上述具有特殊四层结构的三元正极材料前驱体,成本低,工艺稳定。
本申请提供的三元正极材料、锂离子电池正极、锂离子电池,电性能好,使用寿命长,安全性和稳定性高。
附图说明
为了更清楚地说明本申请实施例的技术方案,下面将对实施例中所需要使用的附图作简单地介绍,应当理解,以下附图仅示出了本申请的某些实施例,因此不应被看作是对本申请范围的限定。
图1为本申请提供的三元正极材料前驱体的结构示意图;
图2为实施例1得到的三元正极材料前驱体的剖面SEM照片;
图3为实施例1得到的三元正极材料前驱体的高倍电镜照片;
图4为实施例1得到的三元正极材料前驱体的局部高倍电镜照片;
图5为实施例2得到的三元正极材料前驱体的高倍电镜照片;
图6为实施例2得到的三元正极材料前驱体的局部高倍电镜;
图7为实施例1、2、3、4得到的三元正极材料前驱体的XRD图谱;
图8为实施例2得到的三元正极材料前驱体的剖面SEM照片;
图9为实施例3得到的三元正极材料前驱体的剖面SEM照片;
图10为实施例4得到的三元正极材料前驱体的剖面SEM照片;
图11为对比例1得到的三元正极材料前驱体的剖面SEM照片;
图12为对比例1得到的三元正极材料前驱体的高倍电镜照片;
图13为对比例1得到的三元正极材料前驱体的局部高倍电镜照片;
图14为对比例1得到的三元正极材料前驱体的XRD图谱;
图15为对比例2得到的三元正极材料前驱体的剖面SEM照片;
图16为对比例2得到的三元正极材料前驱体的XRD图谱;
图17为对比例3得到的三元正极材料前驱体的剖面SEM照片;
图18为对比例3得到的三元正极材料前驱体的XRD图谱;
图19为对比例4得到的三元正极材料前驱体的剖面SEM照片。
具体实施方式
如本文所用之术语:
“由……制备”与"包含”同义。本文中所用的术语“包含”、“包括”、“具有”、“含有”或其任何其它变形,意在覆盖非排它性的包括。例如,包含所列要素的组合物、步骤、方法、制品或装置不必仅限于那些要素,而是可以包括未明确列出的其它要素或此种组合物、步骤、方法、制品或装置所固有的要素。
连接词“由……组成”排除任何未指出的要素、步骤或组分。如果用于权利要求中,此短语将使权利要求为封闭式,使其不包含除那些描述的材料以外的材料,但与其相关的常规杂质除外。当短语“由……组成”出现在权利要求主体的子句中而不是紧接在主题之后时,其仅限定在该子句中描述的要素;其它要素并不被排除在作为整体的所述权利要求 之外。
当量、浓度、或者其它值或参数以范围、优选范围、或一系列上限优选值和下限优选值限定的范围表示时,这应当被理解为具体公开了由任何范围上限或优选值与任何范围下限或优选值的任一配对所形成的所有范围,而不论该范围是否单独公开了。例如,当公开了范围“1~5”时,所描述的范围应被解释为包括范围“1~4”、“1~3”、“1~2”、“1~2和4~5”、“1~3和5”等。当数值范围在本文中被描述时,除非另外说明,否则该范围意图包括其端值和在该范围内的所有整数和分数。
在这些实施例中,除非另有指明,所述的份和百分比均按质量计。
“质量份”指表示多个组分的质量比例关系的基本计量单位,1份可表示任意的单位质量,如可以表示为1g,也可表示2.689g等。假如我们说A组分的质量份为a份,B组分的质量份为b份,则表示A组分的质量和B组分的质量之比a:b。或者,表示A组分的质量为aK,B组分的质量为bK(K为任意数,表示倍数因子)。不可误解的是,与质量份数不同的是,所有组分的质量份之和并不受限于100份之限制。
“和/或”用于表示所说明的情况的一者或两者均可能发生,例如,A和/或B包括(A和B)和(A或B)。
如图1所示,本申请提供一种三元正极材料前驱体,由内至外依次包括核层(a核)、第一中间层(b多孔第二层)、第二中间层(c多孔第三层)和壳层(d壳层),所述核层、所述第一中间层、所述第二中间层的孔隙率依次增大,所述壳层的孔隙率最小或无孔。
由图1可知,第一中间层在核层的外部并包覆核层,第二中间层在第一中间层的外部并包覆第一中间层和核层,壳层在最外面,包覆第二中间层以及其内的第一中间层和核层。
在一个可选的实施方式中,所述核层的孔隙率为1.40%-7.96%,所述第一中间层的孔隙率为2.10%-8.37%,所述第二中间层的孔隙率为4.57%-16.72%,所述壳层的孔隙率小于等于1%;
在一个可选的实施方式中,所述核层的孔隙率为2.0%-4.0%,所述第一中间层的孔隙率为3.0%-5.0%,所述第二中间层的孔隙率为7.35%-10.32%,所述壳层的孔隙率小于等于0.5%。
为了评价孔隙率的特点,本申请使用图像解析软件(ImageJ)直接求出各个区域孔隙面积和截面积,由“孔隙率=各区域孔隙面积/各区域截面积×100%”计算得出不同区域的孔隙率,文中孔隙率均由该方法表征。
三元正极材料前驱体内部三层孔隙率逐步增大,满足上述孔隙率范围,这种结构形成相对较多扩散路径,锂离子传输通道变多,降低了锂离子的扩散阻力,有效提高锂离子的扩散速率,从而提高充放电性能、倍率性能、循环性能;壳层孔隙率最小或无孔,为致密少孔外壳结构,从而表现出内松外紧的形态,可承受由充电和放电产生的应力,致密少孔外壳可以保护结构稳定性;并且,正极材料三元前驱体内部结构满足结构的孔隙率一定范围以及壳层少孔致密结构,提升颗粒强度,在电池充放电过程中,颗粒不易开裂,从而增加使用循环保持率和寿命,电池性能优异。
可选的,所述核层的孔隙率可以为1.40%、2%、3%、4%、5%、6%、7%、7.96%或者1.40%-7.96%之间的任一值,所述第一中间层的孔隙率可以为2.10%、3%、4%、5%、6%、7%、8%、8.37%或者2.10%-8.37%之间的任一值,所述第二中间层的孔隙率可以为4.57%、5%、6%、7%、8%、9%、10%、11%、12%、13%、14%、15%、16%、16.72%或者4.57%-16.72%之间的任一值,所述壳层的孔隙率可以为0.05%、0.1%、0.2%、0.3%、0.4%、0.5%、0.6%、0.7%、0.8%、0.9%、1%或者小于等于1%的任一值。
在一个可选的实施方式中,所述三元正极材料前驱体的各层平均厚度均小于等于3μm;
在一个可选的实施方式中,所述核层的直径为1.0μm-3.0μm,所述第一中间层的平均厚度为0.2μm-2.0μm,所述第二中间层的平均厚度为1μm-2.5μm,所述壳层的平均厚度为0.5μm-1.5μm;
可选的,所述核层的直径可以为1.0μm、1.5μm、2μm、2.5μm、3.0μm或者1.0μm-3.0μm之间的任一值,所述第一中间层的平均厚度可以为0.2μm、0.5μm、1μm、1.5μm、2.0μm或者0.2μm-2.0μm之间的任一值,所述第二中间层的平均厚度可以为1μm、1.5μm、2μm、2.5μm或者1μm-2.5μm之间的任一值,所述壳层的平均厚度可以为0.5μm、1μm、1.5μm或者0.5μm-1.5μm之间的任一值;
颗粒内部平均厚度根据上述每个反应步骤的终点粒径大小来确定。
在一个可选的实施方式中,所述三元正极材料前驱体内的一次颗粒沿其径向方向、由内至外呈松散交叉针条状分布;
在一个可选的实施方式中,所述核层整体呈现球形;
在一个可选的实施方式中,所述壳层内的一次颗粒沿所述三元正极材料前驱体的径向方向呈现针条状;
在一个可选的实施方式中,所述三元正极材料前驱体的平均粒径为12μm-15μm;
在一个可选的实施方式中,D95/D50=1.0-1.6;
可选的,所述三元正极材料前驱体的D95/D50可以为1、1.1、1.2、1.3、1.4、1.5、1.6或者1-1.6之间的任一值。
三元正极材料前驱体粒度呈现窄分布,颗粒分布均匀,电性能更优异。
三元正极材料前驱体颗粒表面一次颗粒满足上述颗粒尺寸范围以及粒度分布时,呈现一次颗粒呈现松散针条状交叉均匀分布,用在正极材料的电池上,减少锂离子的扩散阻力,一定程度有利于锂离子传输。
在一个可选的实施方式中,所述三元正极材料前驱体的BET为11m 2/g-17m 2/g。
可选的,所述三元正极材料前驱体的BET可以为11m 2/g、12m 2/g、13m 2/g、14m 2/g、15m 2/g、16m 2/g、17m 2/g或者11m 2/g-17m 2/g之间的任一值。
在一个可选的实施方式中,衍射角2θ为19.2±1°范围的001峰的半峰宽α小于等于0.6;
在一个可选的实施方式中,所述半峰宽α为0.43-0.53;
可选的,所述半峰宽α可以为0.3、0.4、0.43、0.5、0.6或者小于等于0.6的任一值。
在一个可选的实施方式中,衍射角2θ为38.5±1°范围的101峰的半峰宽β小于等于0.7;
在一个可选的实施方式中,所述半峰宽β为0.48-0.58;
可选的,所述半峰宽β可以为0.3、0.4、0.48、0.5、0.58、0.6、0.7或者小于等于0.7的任一值。
在一个可选的实施方式中,所述半峰宽β与所述半峰宽α的比值大于等于1.02,峰强比I(001/101)为1.0-1.2;
在一个可选的实施方式中,所述半峰宽β与所述半峰宽α的比值为1.02-1.25。
可选的,所述半峰宽β与所述半峰宽α的比值可以为1.02、1.1、1.2、1.25或者1.0-1.25之间的任一值。
001面的半峰宽较小,峰强值高,颗粒优先001晶面优先生长,001面结晶度较高,影响一次颗粒生长,制备活性物质前驱体以具有优异的结构稳定性;并且该前驱体物质001峰强大于101峰强,颗粒在001峰的结晶性更具优势,该前驱体物质形成正极活性物质时,结合内部结构孔隙分布,可以发挥优异的输出特性、循环性能、倍率性能,提高电池容量。
在一个可选的实施方式中,其化学通式为Ni xCo yMn z(OH) 2,其中0.8≤x≤0.98,0.01≤y<0.18,0.01≤z<0.17,x+y+z=1。
本申请还提供一种所述的三元正极材料前驱体的制备方法,包括:
将包括镍钴锰三元混合溶液、络合剂、pH调节剂在内的原料进行第一反应得到核层;
调整反应条件,进行第二反应在所述核层的表面形成第一中间层;
调整反应条件,进行第三反应在所述第一中间层的表面形成第二中间层;
调整反应条件,进行第四反应在所述第二中间层的表面形成壳层。
在一个可选的实施方式中,所述第一反应、所述第二反应、所述第三反应、所述第四反应均在搅拌状态下进行,搅拌速度依次降低;
在一个可选的实施方式中,所述第一反应的搅拌速度为200r/min-240r/min,所述第二反应的搅拌速度为180r/min-230r/min,所述第三反应的搅拌速度为100r/min-200r/min,所述第四反应的搅拌速度为40r/min-100r/min。
第四反应降低搅拌强度,降低溶液过饱和度,有利于晶体的界面上生长,并且,第四反应过程中提高体系pH,有利于在晶体颗粒强度稳定,进而形成晶面的致密外壳结构,提高结构稳定。
颗粒内部平均厚度根据上述每个反应步骤的终点粒径大小来确定。
可选的,所述第一反应的搅拌速度可以为200r/min、210r/min、220r/min、230r/min、240r/min或者200r/min-240r/min 之间的任一值,所述第二反应的搅拌速度可以为180r/min、190r/min、200r/min、210r/min、220r/min、230r/min或者180r/min-230r/min之间的任一值,所述第三反应的搅拌速度可以为100r/min、110r/min、120r/min、130r/min、140r/min、150r/min、160r/min、170r/min、180r/min、190r/min、200r/min或者100r/min-200r/min之间的任一值,所述第四反应的搅拌速度可以为40r/min、50r/min、60r/min、70r/min、80r/min、90r/min、100r/min或者40r/min-100r/min之间的任一值;
在一个可选的实施方式中,所述第一反应、所述第二反应、所述第三反应、所述第四反应的过程中,所述镍钴锰三元混合溶液的加入量依次增大;
在一个可选的实施方式中,所述第一反应的过程中,所述镍钴锰三元混合溶液的加入量为80L/h-550L/h;所述第二反应的过程中,所述镍钴锰三元混合溶液的加入量为150L/h-650L/h;所述第三反应、所述第四反应的过程中,所述镍钴锰三元混合溶液的加入量为150L/h-750L/h;
可选的,所述第一反应的过程中,所述镍钴锰三元混合溶液的加入量可以为80L/h、100L/h、200L/h、300L/h、400L/h、500L/h、550L/h或者80L/h-550L/h之间的任一值;所述第二反应的过程中,所述镍钴锰三元混合溶液的加入量可以为150L/h、200L/h、300L/h、400L/h、500L/h、600L/h、650L/h或者150L/h-650L/h之间的任一值;所述第三反应、所述第四反应的过程中,所述镍钴锰三元混合溶液的加入量可以为150L/h、200L/h、300L/h、400L/h、500L/h、600L/h、700L/h、750L/h或者150L/h-750L/h之间的任一值;
在一个可选的实施方式中,所述第一反应、所述第二反应、所述第三反应、所述第四反应的过程中,每个反应过程中,所述镍钴锰三元混合溶液的加入量呈阶梯式增大;
三元正极材料前驱体的四层次结构由第一、二、三步骤的物料分别做晶种再次反应,每一步三元金属流量按阶梯式增长,形成多层内部多孔结构,调整第四反应条件形成壳层致密结构。三元正极材料前驱体颗粒内部结构的孔隙率根据上述每个步骤的pH值调整、氨浓度、原材料三元混合金属盐溶液流量比例来确定。
在一个可选的实施方式中,所述阶梯式增大的比例为10%-100%。
可选的,所述阶梯式增大的比例可以为10%、20%、30%、40%、50%、60%、70%、80%、90%、100%或者10%-100%之间的任一值。
在一个可选的实施方式中,所述第一反应、所述第二反应、所述第三反应的过程中,体系pH逐步降低;所述第四反应的过程中,体系pH高于所述第三反应;
在一个可选的实施方式中,所述第一反应、所述第二反应、所述第三反应、所述第四反应的过程中,体系pH的范围为10-12;
在一个可选的实施方式中,所述第四反应的过程中,体系pH高于第三反应过程中0.10-0.30。
可选的,所述第四反应的过程中,体系pH高于第三反应过程中0.1、0.2、0.3或者0.10-0.30之间的任一值。
通过调整原材料金属盐混合溶液流量比例以及pH,使得第二、三步骤短周期快速生长,内部部分的孔隙率以及分层平均厚度根据上述每个步骤的反应时间、pH值,原材料混合金属盐溶液流量比例来确定。
在一个可选的实施方式中,所述镍钴锰三元混合溶液的浓度为90-130g/L;
可选的,所述镍钴锰三元混合溶液的浓度可以为90g/L、100g/L、110g/L、120g/L、125g/L、130g/L或者90-130g/L之间的任一值;
在一个可选的实施方式中,所述络合剂包括氨水、EDTA、乙二胺、柠檬酸钠、尿素中的一种或多种;
在一个可选的实施方式中,所述络合剂为质量分数为15%-35%的氨水;
可选的,氨水的质量分数可以为15%、20%、25%、30%、35%或者15%-35%之间的任一值;
在一个可选的实施方式中,所述第一反应、所述第二反应、所述第三反应、所述第四反应中,体系中所述氨水的浓度为2.5g/L-6.5g/L;
可选的,所述第一反应、所述第二反应、所述第三反应、所述第四反应中,体系中所述氨水的浓度可以为2.5g/L、3.0g/L、3.5g/L、4.0g/L、4.5g/L、5.0g/L、5.5g/L、6.0g/L、6.5g/L或者2.5g/L-6.5g/L之间的任一值;
在一个可选的实施方式中,第三反应、第四反应的过程中,体系中氨水的浓度高于所述第二反应过程中的氨水的浓度1.0-3.0g/L;
可选的,第三反应、第四反应的过程中,体系中氨水的浓度高于所述第二反应过程中的氨水的浓度1.0g/L、1.5g/L、2.0g/L、2.5g/L、3.0g/L或者1.0-3.0g/L之间的任一值;
在一个可选的实施方式中,所述pH调节剂包括氢氧化钠、氢氧化钾、碳酸氢钠、纯碱中的一种或多种;
在一个可选的实施方式中,所述pH调节剂为质量分数为25%-50%的氢氧化钠水溶液。
可选的,所述氢氧化钠水溶液的质量分数可以为25%、30%、35%、40%、45%、50%或者25%-50%之间的任一值。
本申请还提供一种三元正极材料,由内至外依次包括A层、B层、C层和D层,所述A层、所述B层、所述C层的孔隙率依次增大,所述D层的孔隙率最小或无孔;
在一个可选的实施方式中,所述三元正极材料使用所述的三元正极材料前驱体烧制得到。
例如,以锂源化合物和上述三元正极材料前驱体为原料烧制得到三元正极材料。
本申请还提供一种锂离子电池正极,包括所述的三元正极材料。
本申请还提供一种锂离子电池,包括所述的锂离子电池正极。
本申请还提供一种涉电设备,包括所述的锂离子电池。
下面将结合具体实施例对本申请的实施方案进行详细描述,但是本领域技术人员将会理解,下列实施例仅用于说明本申请,而不应视为限制本申请的范围。实施例中未注明具体条件者,按照常规条件或制造商建议的条件进行。所用试剂或仪器未注明生产厂商者,均为可以通过市售购买获得的常规产品。
实施例1
本实施例中,制备具备四层内部多孔且致密壳层结构(核、两层中间层、壳)的正极材料活性物质高镍三元前驱体物质,合成化学式Ni 0.85Co 0.10Mn 0.05(OH) 2
制备方法如以下步骤:
1.选取材料:使用硫酸镍(NiSO 4·6H 2O)、硫酸钴(CoSO 4·7H 2O)和硫酸锰(MnSO 4·H 2O)。
金属原料按镍、钴、锰摩尔按摩尔比例为0.85:0.10:0.05,配成浓度100g/L三元混合金属盐溶液;
选用质量分数32%的液碱,20%氨水溶液;选用10m 3不锈钢材质反应釜,1.3m 3不锈钢材质浓缩机。
2.第一步骤,共沉淀造内核A:1#反应釜中加入5.0m 3纯水做底液,加入氨水和液碱(氢氧化钠水溶液)调节氨浓度和pH,调整体系氨浓度4.0g/L,pH为11.90;反应温度升至60℃,搅拌转速控制在220r/min,条件达到后同时通入镍钴锰三元金属混合溶液、液碱、氨水进行共沉淀反应。其中,三元金属流量分阶梯式增长,开始三元金属流量100L/h,终点三元金属流量500L/h。终点pH调整为11.20。反应釜到达一定液位时开启浓缩机,料浆打循环,外排母液,等料浆粒度D50达到2.0-3.0μm时,停止进料。
3.第二步骤,共沉淀形成多孔第二中间层结构B:将第一步骤的料浆定量1.8m 3转入2#反应釜中,补加纯水至5.0m 3,搅拌转速控制220r/min,加入氨水和液碱,调节氨浓度以及pH值,体系氨浓度4.0g/L,pH为11.00,温度升至60℃,同时通入三元金属混合溶液、氨水溶液、氢氧化钠溶液进行共沉淀反应;其中,三元金属流量分阶梯式增长,开始三元金属流量200L/h,终点三元金属流量450L/h。反应釜到达一定液位时开启浓缩机,料浆打循环,外排母液,等料浆粒度D50达到3.0-5.0μm时,停止进料。脱水得干基料。
4.第三步骤,形成多孔第三层中间层C:向3#反应釜补加纯水5.5m 3,定量投入第二步骤脱水干基料75kg,在180r/min搅拌条件下,加入氨水和液碱,调节氨浓度以及pH值,调试体系氨浓度5.5g/L,温度升至60℃,然后同时通入三元混合溶液、氨水溶液、氢氧化钠溶液进行共沉淀反应;其中,三元金属流量分阶梯式增长,开始三元金属流量200L/h,终点三元金属流量520L/h。开始pH控制10.50。
5.第四步骤,形成致密外壳D:在第三步骤反应条件基础上,调整终点反应搅拌转速为60r/min,终点pH控制10.65,搅拌下降,pH上升。第四步反应降低搅拌强度,降低溶液过饱和度,有利于晶体的界面上生长,并且第四反应 过程中提高体系pH,有利于在晶体颗粒强度稳定,进而形成晶面的致密外壳结构。
反应釜到达一定液位时开启浓缩机,料浆打循环,外排母液,等料浆粒度D50达到13.0-14.0μm时,停止进料。
6.后处理:停止反应后的物料用适量的稀碱和纯水进行洗涤物料,洗涤物料的Na和S含量分别小于400ppm以及3000ppm;洗涤后的固体颗粒物料在100℃下干燥24小时,过400目筛网筛分,包装密封。即得到一种四层内部多孔且致密壳层结构的正极材料活性物质高镍三元前驱体物质。
实施例2
本实施例中,制备具备四层内部多孔且致密壳层结构(核、两层中间层、壳)的正极材料活性物质高镍三元前驱体物质,合成化学式Ni 0.80Co 0.10Mn 0.10(OH) 2
制备方法如以下步骤:
1.选取材料:使用硫酸镍(NiSO 4·6H 2O)、硫酸钴(CoSO 4·7H 2O)和硫酸锰(MnSO 4·H 2O)。
金属原料按镍、钴、锰摩尔按摩尔比例为0.80:0.10:0.10,配成浓度105g/L三元混合金属盐溶液;
选用质量分数32%的液碱,20%氨水溶液;选用10m 3不锈钢材质反应釜,1.3m 3不锈钢材质浓缩机。
2.第一步骤,共沉淀造内核A:1#反应釜中加入5.0m 3纯水做底液,加入氨水和液碱调节氨浓度和pH,调整体系氨浓度4.0g/L,pH为11.90;反应温度升至60℃,搅拌转速控制在220r/min,条件达到后同时通入镍钴锰三元金属混合溶液、液碱、氨水进行共沉淀反应。其中,三元金属流量分阶梯式增长,开始三元金属流量100L/h,终点三元金属流量500L/h。终点pH调整为11.20。反应釜到达一定液位时开启浓缩机,料浆打循环,外排母液,等料浆粒度D50达到2.0-3.0μm时,停止进料。
3.第二步骤,共沉淀形成多孔第二中间层结构B:将第一步骤的料浆定量1.8m 3转入2#反应釜中,补加纯水至5.0m 3,搅拌转速控制220r/min,加入氨水和液碱,调节氨浓度以及pH值,体系氨浓度4.0g/L,pH为11.00,温度升至60℃,同时通入三元金属混合溶液、氨水溶液、氢氧化钠溶液进行共沉淀反应;三元金属流量分阶梯式增长,开始三元金属流量200L/h,终点三元金属流量480L/h。反应釜到达一定液位时开启浓缩机,料浆打循环,外排母液,等料浆粒度D50达到3.0-5.0μm时,停止进料。脱水得干基料。
4.第三步骤,形成多孔第三层中间层C及致密外壳D:向3#反应釜补加纯水5.5m 3,定量投入第二步骤脱水干基料80kg,在180r/min搅拌条件下,加入氨水和液碱,调节氨浓度以及pH值,调试体系氨浓度5.5g/L,温度升至60℃,然后同时通入三元混合溶液、氨水溶液、氢氧化钠溶液进行共沉淀反应;三元金属流量分阶梯式增长,开始三元金属流量200L/h,终点三元金属流量550L/h。开始pH控制10.55。
5.第四步骤,形成致密外壳D:在第三步骤反应条件基础上,调整终点阶段反应搅拌转速为60r/min,终点阶段pH控制10.70,搅拌下降,pH上升。第四步反应降低搅拌强度,降低溶液过饱和度,有利于晶体的界面上生长,并且第四反应过程中提高体系pH,有利于在晶体颗粒强度稳定,进而形成晶面的致密外壳结构。
反应釜到达一定液位时开启浓缩机,料浆打循环,外排母液,等料浆粒度D50达到13.0-14.0μm时,停止进料。
6.后处理:停止反应后的物料用适量的稀碱和纯水进行洗涤物料,洗涤物料的Na和S含量分别小于400ppm以及3000ppm;洗涤后的固体颗粒物料在100℃下干燥24小时,过400目筛网筛分,包装密封。即得到一种四层内部多孔且致密壳层结构的正极材料活性物质高镍三元前驱体物质。
实施例3
本实施例中,制备具备四层内部多孔且致密壳层结构(核、两层中间层、壳)的正极材料活性物质高镍三元前驱体物质,合成化学式Ni 0.90Co 0.05Mn 0.05(OH) 2
制备方法如以下步骤:
1.选取材料:使用硫酸镍(NiSO 4·6H 2O)、硫酸钴(CoSO 4·7H 2O)和硫酸锰(MnSO 4·H 2O)。
金属原料按镍、钴、锰摩尔按摩尔比例为0.90:0.05:0.05,配成浓度110g/L三元混合金属盐溶液;
选用质量分数32%的液碱,20%氨水溶液;选用10m 3不锈钢材质反应釜,1.3m 3不锈钢材质浓缩机。
2.第一步骤,共沉淀造内核A:1#反应釜中加入5.0m 3纯水做底液,加入氨水和液碱调节氨浓度和pH,调整体系氨浓度4.0g/L,pH为11.90;反应温度升至60℃,搅拌转速控制在220r/min,条件达到后同时通入镍钴锰三元金属混合溶液、液碱、氨水进行共沉淀反应。其中,三元金属流量分阶梯式增长,开始三元金属流量100L/h,终点三元金属流量500L/h。终点pH调整为11.20。反应釜到达一定液位时开启浓缩机,料浆打循环,外排母液,等料浆粒度D50达到2.0-3.0μm时,停止进料。
3.第二步骤,共沉淀形成多孔第二中间层结构B:将第一步骤的料浆定量1.8m 3转入2#反应釜中,补加纯水至5.0m 3,搅拌转速控制220r/min,加入氨水和液碱,调节氨浓度以及pH值,体系氨浓度4.0g/L,pH为11.00,温度升至60℃,同时通入三元金属混合溶液、氨水溶液、氢氧化钠溶液进行共沉淀反应;三元金属流量分阶梯式增长,开始三元金属流量200L/h,终点三元金属流量500L/h。反应釜到达一定液位时开启浓缩机,料浆打循环,外排母液,等料浆粒度D50达到3.0-5.0μm时,停止进料。脱水得干基料。
4.第三步骤,形成多孔第三层中间层C及致密外壳D:向3#反应釜补加纯水5.5m 3,定量投入第二步骤脱水干基料85kg,在180r/min搅拌条件下,加入氨水和液碱,调节氨浓度以及pH值,调试体系氨浓度5.5g/L,温度升至60℃,然后同时通入三元混合溶液、氨水溶液、氢氧化钠溶液进行共沉淀反应;其中,三元金属流量分阶梯式增长,开始三元金属流量200L/h,终点三元金属流量600L/h。开始阶段pH控制10.60。
5.第四步骤,形成致密外壳D:在第三步骤反应条件基础上,调整终点阶段反应搅拌转速为60r/min,终点阶段pH控制10.75,搅拌下降,pH上升。第四步反应降低搅拌强度,降低溶液过饱和度,有利于晶体的界面上生长,并且第四反应过程中提高体系pH,有利于在晶体颗粒强度稳定,进而形成晶面的致密外壳结构。
反应釜到达一定液位时开启浓缩机,料浆打循环,外排母液,等料浆粒度D50达到13.0-14.0μm时,停止进料。
6.后处理:停止反应后的物料用适量的稀碱和纯水进行洗涤物料,洗涤物料的Na和S含量分别小于400ppm以及3000ppm;洗涤后的固体颗粒物料在100℃下干燥24小时,过400目筛网筛分,包装密封。即得到一种四层内部多孔且致密壳层结构的正极材料活性物质高镍三元前驱体物质。
实施例4
本实施例中,制备具备四层内部多孔且致密壳层结构(核、两层中间层、壳)的正极材料活性物质高镍三元前驱体物质,合成化学式Ni 0.93Co 0.04Mn 0.03(OH) 2
制备方法如以下步骤:
1.选取材料:使用硫酸镍(NiSO 4·6H 2O)、硫酸钴(CoSO 4·7H 2O)和硫酸锰(MnSO 4·H 2O)。
金属原料按镍、钴、锰摩尔按摩尔比例为0.93:0.04:0.03,配成浓度125g/L三元混合金属盐溶液;
选用质量分数32%的液碱,20%氨水溶液;选用10m 3不锈钢材质反应釜,1.3m 3不锈钢材质浓缩机。
2.第一步骤,共沉淀造内核A:1#反应釜中加入5.0m 3纯水做底液,加入氨水和液碱调节氨浓度和pH,调整体系氨浓度4.0g/L,pH为11.90;反应温度升至60℃,搅拌转速控制在220r/min,条件达到后同时通入镍钴锰三元金属混合溶液、液碱、氨水进行共沉淀反应。其中,三元金属流量分阶梯式增长,开始三元金属流量100L/h,终点三元金属流量500L/h。终点pH调整为11.20。反应釜到达一定液位时开启浓缩机,料浆打循环,外排母液,等料浆粒度D50达到2.0-3.0μm时,停止进料。
3.第二步骤,共沉淀形成多孔第二中间层结构B:将第一步骤的料浆定量1.8m 3转入2#反应釜中,补加纯水至5.0m 3,搅拌转速控制220r/min,加入氨水和液碱,调节氨浓度以及pH值,体系氨浓度4.0g/L,pH为11.00,温度升至60℃,同时通入三元金属混合溶液、氨水溶液、氢氧化钠溶液进行共沉淀反应;其中,三元金属流量分阶梯式增长,开始三元金属流量200L/h,终点三元金属流量550L/h。反应釜到达一定液位时开启浓缩机,料浆打循环,外排母液,等料浆粒度D50达到3.0-5.0μm时,停止进料。脱水得干基料。
4.第三步骤,形成多孔第三层中间层C及致密外壳D:向3#反应釜补加纯水5.5m 3,定量投入第二步骤脱水干基料90kg,在180r/min搅拌条件下,加入氨水和液碱,调节氨浓度以及pH值,调试体系氨浓度5.5g/L,温度升至60℃,然 后同时通入三元混合溶液、氨水溶液、氢氧化钠溶液进行共沉淀反应;其中,三元金属流量分阶梯式增长,开始三元金属流量200L/h,终点三元金属流量650L/h。开始阶段pH控制10.65。
5.第四步骤,形成致密外壳D:在第三步骤反应条件基础上,调整终点阶段反应搅拌转速为60r/min,终点阶段pH控制10.85,搅拌下降,pH上升。第四步反应降低搅拌强度,降低溶液过饱和度,有利于晶体的界面上生长,并且第四反应过程中提高体系pH,有利于在晶体颗粒强度稳定,进而形成晶面的致密外壳结构。
反应釜到达一定液位时开启浓缩机,料浆打循环,外排母液,等料浆粒度D50达到13.0-14.0μm时,停止进料。
6.后处理:停止反应后物料用适量的稀碱和纯水进行洗涤物料,洗涤物料的Na和S含量分别小于400ppm以及3000ppm;洗涤后的固体颗粒物料在100℃下干燥24小时,过400目筛网筛分,包装密封。即得到一种四层内部多孔且致密壳层结构的正极材料活性物质高镍三元前驱体物质。
对比例1
本对比例中,制备具备三层内部致密少孔壳层结构(核、中间层、壳)的正极材料活性物质高镍三元前驱体物质,合成化学式Ni 0.85Co 0.10Mn 0.05(OH) 2
制备方法如以下步骤:
1.选取材料:使用硫酸镍(NiSO 4·6H 2O)、硫酸钴(CoSO 4·7H 2O)和硫酸锰(MnSO 4·H 2O)。
金属原料按镍、钴、锰摩尔按摩尔比例为0.85:0.10:0.05,配成浓度110g/L三元混合金属盐溶液;
选用质量分数32%的液碱,20%氨水溶液;选用10m 3不锈钢材质反应釜,1.3m 3不锈钢材质浓缩机。
2.第一步骤:1#反应釜中加入5.0m 3纯水做底液,加入氨水和液碱调节氨浓度和pH,调整体系氨浓度4.0g/L,pH为11.90;反应温度升至60℃,搅拌转速控制在220r/min,条件达到后同时通入镍钴锰三元金属混合溶液、液碱、氨水进行共沉淀反应。其中,三元金属流量分阶梯式增长,开始三元金属流量100L/h,终点三元金属流量500L/h。终点pH调整为11.20。反应釜到达一定液位时开启浓缩机,料浆打循环,外排母液,等料浆粒度D50达到2.0-3.0μm时,停止进料。
3.第二步骤:将第一步骤的料浆定量1.8m 3转入2#反应釜中,补加纯水至5.0m 3,搅拌转速控制220r/min,加入氨水和液碱,调节氨浓度以及pH值,体系氨浓度4.0g/L,pH为11.00,温度升至60℃,同时通入三元金属混合溶液、氨水溶液、氢氧化钠溶液进行共沉淀反应;其中,三元金属流量分阶梯式增长,开始三元金属流量200L/h,终点三元金属流量500L/h。反应釜到达一定液位时开启浓缩机,料浆打循环,外排母液,等料浆粒度D50达到3.0-5.0μm时,停止进料。脱水得干基料。
4.第三步骤:向3#反应釜补加纯水5.5m 3,定量投入第二步骤脱水干基料75kg,在180r/min搅拌条件下,加入氨水和液碱,调节氨浓度以及pH值,调试体系氨浓度7.5g/L,温度升至60℃,然后同时通入三元混合溶液、氨水溶液、氢氧化钠溶液进行共沉淀反应;其中,三元金属流量分阶梯式增长,开始三元金属流量200L/h,终点三元金属流量500L/h。开始阶段pH控制10.45,终点阶段pH控制10.60;终点阶段反应搅拌转速逐步下降至60r/min。反应釜到达一定液位时开启浓缩机,料浆打循环,外排母液,等料浆粒度D50达到13.0-14.0μm时,停止进料。
5.后处理:停止反应后的物料用适量的稀碱和纯水进行洗涤物料,洗涤物料的Na和S含量分别小于400ppm以及3000ppm;将洗涤后的固体颗粒物料在100℃下干燥24小时,过400目筛网筛分,包装密封。
较实施例,对比例1与实施例的步骤,三元金属流量基本一致,对比例调整终点pH,氨水浓度即可得到三层内部致密结构的三元前驱体物质。
对比例2
本对比例中,制备具备二层内部致密少孔壳层结构(核、壳)的正极材料活性物质高镍三元前驱体物质,合成化学式Ni 0.80Co 0.15Mn 0.05(OH) 2
制备方法如以下步骤:
1.选取材料:使用硫酸镍(NiSO 4·6H 2O)、硫酸钴(CoSO 4·7H 2O)和硫酸锰(MnSO 4·H 2O)。
金属原料按镍、钴、锰摩尔按摩尔比例为0.80:0.15:0.05,配成浓度110g/L三元混合金属盐溶液;
选用质量分数32%的液碱,20%氨水溶液;选用10m 3不锈钢材质反应釜,1.3m 3不锈钢材质浓缩机。
2.第一步骤:1#反应釜中加入5.0m 3纯水做底液,加入氨水和液碱调节氨浓度和pH,调整体系氨浓度4.0g/L,pH为11.90;反应温度升至60℃,搅拌转速控制在220r/min,条件达到后同时通入镍钴锰三元金属混合溶液、液碱、氨水进行共沉淀反应。其中,三元金属流量分阶梯式增长,开始三元金属流量100L/h,终点三元金属流量500L/h。终点pH调整为11.20。反应釜到达一定液位时开启浓缩机,料浆打循环,外排母液,等料浆粒度D50达到2.0-3.0μm时,停止进料。
3.第二步骤:将第一步骤的料浆定量1.8m 3转入2#反应釜中,补加纯水至5.0m 3,搅拌转速控制220r/min,加入氨水和液碱,调节氨浓度以及pH值,体系氨浓度4.0g/L,pH为11.00,温度升至60℃,同时通入三元金属混合溶液、氨水溶液、氢氧化钠溶液进行共沉淀反应;其中,三元金属流量分阶梯式增长,开始三元金属流量200L/h,终点三元金属流量500L/h。反应釜到达一定液位时开启浓缩机,料浆打循环,外排母液,等料浆粒度D50达到3.0-5.0μm时,停止进料。脱水得干基料。
4.第三步骤:向3#反应釜补加纯水5.0m 3,定量投入第二步骤脱水干基料75kg,在180r/min搅拌条件下,加入氨水和液碱,调节氨浓度以及pH值,调试体系氨浓度8.0g/L,温度升至60℃,然后同时通入三元混合溶液、氨水溶液、氢氧化钠溶液进行共沉淀反应;其中,三元金属流量分阶梯式增长,开始三元金属流量200L/h,终点三元金属流量500L/h。开始阶段pH控制10.40,终点阶段pH控制10.55,终点阶段反应搅拌转速逐步下降至60r/min。反应釜到达一定液位时开启浓缩机,料浆打循环,外排母液,等料浆粒度D50达到13.0-14.0μm时,停止进料。
5.后处理:停止反应后的物料用适量的稀碱和纯水进行洗涤物料,洗涤物料的Na和S含量分别小于400ppm以及3000ppm;洗涤后的固体颗粒物料在100℃下干燥24小时,过400目筛网筛分,包装密封。
较实施例,对比例2与实施例的步骤,三元金属流量基本一致;对比例调整终点pH,氨水浓度即可得到三层内部致密少孔结构的三元前驱体物质。
对比例3
本对比例中,通过两个步骤制备内部致密结构(核、壳)的正极材料活性物质高镍三元前驱体物质,合成化学式Ni 0.85Co 0.10Mn 0.05(OH) 2
制备方法如以下步骤:
1.选取材料:使用硫酸镍(NiSO 4·6H 2O)、硫酸钴(CoSO 4·7H 2O)和硫酸锰(MnSO 4·H 2O)。
金属原料按镍、钴、锰摩尔按摩尔比例为0.85:0.10:0.05,配成浓度110g/L三元混合金属盐溶液;
选用质量分数32%的液碱,20%氨水溶液;选用10m 3不锈钢材质反应釜,1.3m 3不锈钢材质浓缩机。
2.第一步骤:1#反应釜中加入8.0m 3纯水做底液,加入氨水和液碱调节氨浓度和pH,调整体系氨浓度4.0g/L,pH为11.90;反应温度升至60℃,搅拌转速控制在220r/min,条件达到后同时通入镍钴锰三元金属混合溶液、液碱、氨水进行共沉淀反应。其中,三元金属流量分阶梯式增长,开始三元金属流量100L/h,终点三元金属流量500L/h,终点pH调整为11.20。
反应釜到达一定液位时开启浓缩机,料浆打循环,外排母液,等料浆粒度D50达到3.0-5.0μm时,停止进料。
3.第二步骤:将第一步骤的料浆脱水干基料80kg转入2#反应釜中,补加纯水至5.0m 3,搅拌转速控制220r/min,加入氨水和液碱,调节氨浓度以及pH值,体系氨浓度6.0g/L,pH为10.80,温度升至60℃,同时通入三元金属混合溶液、氨水溶液、氢氧化钠溶液进行共沉淀反应;其中,三元金属流量分阶梯式增长,开始三元金属流量200L/h,终点三元金属流量600L/h;反应过程中搅拌转速逐步下降,终点转速100r/min;反应体系pH逐步上升,终点pH为11.20。
反应釜到达一定液位时开启浓缩机,料浆打循环,外排母液,等料浆粒度D50达到12.0-14.0μm时,停止进料。
相比实施例,对比例3通过两个步骤,第二步骤体系pH逐步上升,终点pH达到11.20与第一步骤终点pH基本一致,得到内部致密结构(核、壳)的三元前驱体物质;未能得到实施例中的四层内部多孔外壳致密的三元前驱体物质。
对比例4
本对比例中,制备低镍(5系列)内部致密无孔无层结构的正极材料活性物质高镍三元前驱体物质,合成化学式Ni 0.50Co 0.20Mn 0.30(OH) 2
制备方法如以下步骤:
1.选取材料:使用硫酸镍(NiSO 4·6H 2O)、硫酸钴(CoSO 4·7H 2O)和硫酸锰(MnSO 4·H 2O)。
金属原料按镍、钴、锰摩尔按摩尔比例为0.50:0.20:0.30,配成浓度110g/L三元混合金属盐溶液;
选用质量分数32%的液碱,20%氨水溶液;选用10m 3不锈钢材质反应釜,1.3m 3不锈钢材质浓缩机。
2.第一步骤:1#反应釜中加入8.0m 3纯水做底液,加入氨水和液碱调节氨浓度和pH,调整体系氨浓度4.0g/L,pH为10.95;反应温度升至60℃,搅拌转速控制在220r/min,条件达到后同时通入镍钴锰三元金属混合溶液、液碱、氨水进行共沉淀反应。其中,三元金属流量500L/h,液碱流量185L/H,氨水流量17L/H,反应釜到达一定液位时外排母液,物料浓度随之上升,料浆粒度D50稳定控制达到7.0-9.0μm时,反应体系停止进料。
3.第二步骤:2#反应釜中定量转入第一步骤7.5m 3料浆,加入氨水和液碱调节氨浓度和pH,调整体系氨浓度5.0g/L,pH为10.80;反应温度升至60℃,搅拌转速控制在200r/min,条件达到后同时通入镍钴锰三元金属混合溶液、液碱、氨水进行共沉淀反应。其中在反应过程中,三元金属流量固定不变,搅拌转速保持不变,pH保持不变。
反应釜到达一定液位时开启浓缩机,料浆打循环,外排母液,等料浆粒度D50达到10.0-13.0μm时,停止进料。
相比实施例,对比例4的低镍系列产品通过两个步骤,高转速搅拌,流量保持不变、pH保持不变,得到内部致密无孔无层次结构;未能得到实施例中的四层内部多孔外壳致密的三元前驱体物质。
对实施例和对比例所得前驱体进行测试,结果如图2至图19所示。具体的:图2为实施例1得到的三元正极材料前驱体的剖面SEM照片;图3为实施例1得到的三元正极材料前驱体的高倍电镜照片;图4为实施例1得到的三元正极材料前驱体的局部高倍电镜照片;图5为实施例2得到的三元正极材料前驱体的高倍电镜照片;图6为实施例2得到的三元正极材料前驱体的局部高倍电镜照片;图7为实施例1、2、3、4得到的三元正极材料前驱体的XRD图谱(右侧计算,右上至下依次为实施例3、实施例4、实施例2和实施例1);图8为实施例2得到的三元正极材料前驱体的剖面SEM照片;图9为实施例3得到的三元正极材料前驱体的剖面SEM照片;图10为实施例4得到的三元正极材料前驱体的剖面SEM照片;图11为对比例1得到的三元正极材料前驱体的剖面SEM照片;图12为对比例1得到的三元正极材料前驱体的高倍电镜照片;图13为对比例1得到的三元正极材料前驱体的局部高倍电镜照片;图14为对比例1得到的三元正极材料前驱体的XRD图谱;图15为对比例2得到的三元正极材料前驱体的剖面SEM照片;图16为对比例2得到的三元正极材料前驱体的XRD图谱;图17为对比例3得到的三元正极材料前驱体的剖面SEM照片;图18为对比例3得到的三元正极材料前驱体的XRD图谱;图19为对比例4得到的三元正极材料前驱体的剖面SEM照片。
由图2、图8、图9、图10可知,实施例获得的三元前驱体具备包含核、两层中间层和壳的四层结构并呈现出四层内部多孔且致密少孔壳层结构。
由图11可知,对比例1获得的前驱体包括核、一层中间层和壳三层结构,内部至壳层均少孔致密。
由图15、图17可知,对比例2、对比例3获得的前驱体包括核和壳两层结构,内部至壳层均少孔致密。
由图19可知,对比例4(低镍)获得的前驱体内部至壳层均少孔致密,无层次结构。
实施例及对比例得到的三元正极材料前驱体的性能参数如表1所示:
表1性能参数
Figure PCTCN2022098559-appb-000001
将2000g实施例所制得的前驱体和LiOH·H 2O按照摩尔比1:1.03的比例,通过高速混合机混合均匀,在空气气氛下采用箱式炉进行烧结,烧结温度为780℃,高温烧结时长为12h,冷却至室温后进行粉碎、过筛处理,得到镍钴锰三元单晶正极材料。
采用扣式半电进行电化学性能测试:上述正极材料、导电碳黑、粘结剂PVDF(聚偏氟乙烯)按照8:1:1调成浆料,涂在铝箔上制成正极片,负极片采用金属锂片,电解液采用1mol/L LiPF 6/EC:DMC(体积比1:1),在真空手套箱中将电池壳、正负电极片、隔膜、弹片、垫片组装成扣式电池。采用蓝电测试系统进行电化学性能测试。
常温下,在3.0-4.3V条件下进行1C循环50周测试,电化学性能如表2所示:
表2电化学性能
Figure PCTCN2022098559-appb-000002
表1可知,相比对比例1、2、3,实施例1、2、3、4三元前驱体颗粒从二、三层致密结构变四层内部多孔且外壳致密稳定结构,对比例4(低镍)为无层次致密结构;实施例中的三元前驱体内部多层且外壳致密稳定结构孔隙率高于对比例,且在充放电时颗粒结构不易开裂,产品颗粒的结构性、电化学性能均更加优异。
表1可知,相比对比例3、4,实施例1、2、3、4中粒度分布宽度在1.20±0.05范围内,颗粒粒度分布呈现窄分布,分布更加均匀。
表1可知,通过XRD衍射,相比对比例1、2、3,实施例001峰半峰宽小于对比例;实施例FWHM(101/001)比值为1.1-1.2,实施例I(001/101)为1.1-1.2,则呈现出001峰半峰宽小于101峰,001峰强高于101峰强,证明实施例物质在001峰优先生长,物质结晶性更强,结构更加稳定。相比对比例4(低镍产品),由于对比例4是低镍高钴高锰比例的物质,晶胞参数大,001半峰宽越小,001峰强很高,由于比例不一致,不作对比;从电化学性能表2可知,高镍产品有更佳的电化学性能。
由表2电化学性能可知,相比对比例1、2、3、4,实施例中的倍率性能达到93.45%-95.18%,提升了2.49%-6.19%;循环寿命达到97.75%-98.63%,提升了5.19%-7.70%。
因此,本申请的三元正极材料高镍前驱体有更佳优异性能。
本申请提供的三元正极材料前驱体物质,颗粒内部四层结构突破现有的致密结构,内部结构呈现多层多孔稳定结构,进一步为正极材料三元前驱体颗粒内部层次结构提供新的方向。
最后应说明的是:以上各实施例仅用以说明本申请的技术方案,而非对其限制;尽管参照前述各实施例对本申请进行了详细的说明,本领域的普通技术人员应当理解:其依然可以对前述各实施例所记载的技术方案进行修改,或者对其中部分或者全部技术特征进行等同替换;而这些修改或者替换,并不使相应技术方案的本质脱离本申请各实施例技术方案的范围。此外,本领域的技术人员能够理解,尽管在此的一些实施例包括其它实施例中所包括的某些特征而不是其它特征,但是不同实施例的特征的组合意味着处于本申请的范围之内并且形成不同的实施例。例如,在上面的权利要求书中,所要求保护的实施例的任意之一都可以以任意的组合方式来使用。公开于该背景技术部分的信息仅仅旨在加深对本申请的总体背景技术的理解,而不应当被视为承认或以任何形式暗示该信息构成已为本领域技术人员所公知的现有技术。

Claims (16)

  1. 一种三元正极材料前驱体,其特征在于,由内至外依次包括核层、第一中间层、第二中间层和壳层,所述核层、所述第一中间层、所述第二中间层的孔隙率依次增大,所述壳层的孔隙率最小或无孔。
  2. 根据权利要求1所述的三元正极材料前驱体,其特征在于,所述核层的孔隙率为1.40%-7.96%,所述第一中间层的孔隙率为2.10%-8.37%,所述第二中间层的孔隙率为4.57%-16.72%,所述壳层的孔隙率小于等于1%;
    优选地,所述核层的孔隙率为2.0%-4.0%,所述第一中间层的孔隙率为3.0%-5.0%,所述第二中间层的孔隙率为7.35%-10.32%,所述壳层的孔隙率小于等于0.5%。
  3. 根据权利要求1所述的三元正极材料前驱体,其特征在于,各层平均厚度均小于等于3μm;
    优选地,所述核层的直径为1.0μm-3.0μm,所述第一中间层的平均厚度为0.2μm-2.0μm,所述第二中间层的平均厚度为1μm-2.5μm,所述壳层的平均厚度为0.5μm-1.5μm。
  4. 根据权利要求1所述的三元正极材料前驱体,其特征在于,所述三元正极材料前驱体内的一次颗粒沿其径向方向、由内至外呈松散交叉针条状分布;
    优选地,所述核层整体呈现球形;
    优选地,所述壳层内的一次颗粒沿所述三元正极材料前驱体的径向方向呈现针条状。
  5. 根据权利要求1所述的三元正极材料前驱体,其特征在于,所述三元正极材料前驱体的平均粒径为12μm-15μm;
    优选地,D95/D50=1.0-1.6;
    优选地,所述三元正极材料前驱体的BET为11m 2/g-17m 2/g。
  6. 根据权利要求1所述的三元正极材料前驱体,其特征在于,衍射角2θ为19.2±1°范围的001峰的半峰宽α小于等于0.6;
    优选地,所述半峰宽α为0.43-0.53;
    优选地,衍射角2θ为38.5±1°范围的101峰的半峰宽β小于等于0.7;
    优选地,所述半峰宽β为0.48-0.58;
    优选地,所述半峰宽β与所述半峰宽α的比值大于等于1.02,峰强比I(001/101)为1.0-1.2;
    优选地,所述半峰宽β与所述半峰宽α的比值为1.02-1.25。
  7. 根据权利要求1-6任一项所述的三元正极材料前驱体,其特征在于,其化学通式为Ni xCo yMn z(OH) 2,其中0.8≤x≤0.98,0.01≤y<0.18,0.01≤z<0.17,x+y+z=1。
  8. 一种三元正极材料前驱体的制备方法,其特征在于,包括:
    将包括镍钴锰三元混合溶液、络合剂、pH调节剂在内的原料进行第一反应得到核层;
    调整反应条件,进行第二反应在所述核层的表面形成第一中间层;
    调整反应条件,进行第三反应在所述第一中间层的表面形成第二中间层;
    调整反应条件,进行第四反应在所述第二中间层的表面形成壳层。
  9. 根据权利要求8所述的制备方法,其特征在于,所述第一反应、所述第二反应、所述第三反应、所述第四反应均在搅拌状态下进行,搅拌速度依次降低;
    优选地,所述第一反应的搅拌速度为200r/min-240r/min,所述第二反应的搅拌速度为180r/min-230r/min,所述第三反应的搅拌速度为100r/min-200r/min,所述第四反应的搅拌速度为40r/min-100r/min。
  10. 根据权利要求8所述的制备方法,其特征在于,所述第一反应、所述第二反应、所述第三反应、所述第四反应的过程中,所述镍钴锰三元混合溶液的加入量依次增大;
    优选地,所述第一反应的过程中,所述镍钴锰三元混合溶液的加入量为80L/h-550L/h;所述第二反应的过程中,所述镍钴锰三元混合溶液的加入量为150L/h-650L/h;所述第三反应、所述第四反应的过程中,所述镍钴锰三元混合溶液的 加入量为150L/h-750L/h;
    优选地,所述第一反应、所述第二反应、所述第三反应、所述第四反应的过程中,每个反应过程中,所述镍钴锰三元混合溶液的加入量呈阶梯式增大;
    优选地,所述阶梯式增大的比例为10%-100%。
  11. 根据权利要求8所述的制备方法,其特征在于,所述第一反应、所述第二反应、所述第三反应的过程中,体系pH逐步降低;所述第四反应的过程中,体系pH高于所述第三反应;
    优选地,所述第一反应、所述第二反应、所述第三反应、所述第四反应的过程中,体系pH的范围为10-12;
    优选地,所述第四反应的过程中,体系pH高于第三反应过程中0.10-0.30。
  12. 根据权利要求8-11任一项所述的制备方法,其特征在于,所述镍钴锰三元混合溶液的浓度为90-130g/L;
    优选地,所述络合剂包括氨水、EDTA、乙二胺、柠檬酸钠、尿素中的一种或多种;
    优选地,所述络合剂为质量分数为15%-35%的氨水;
    优选地,所述第一反应、所述第二反应、所述第三反应、所述第四反应中,体系中所述氨水的浓度为2.5g/L-6.5g/L;
    优选地,第三反应、第四反应的过程中,体系中氨水的浓度高于所述第二反应过程中的氨水的浓度1.0-3.0g/L;
    优选地,所述pH调节剂包括氢氧化钠、氢氧化钾、碳酸氢钠、纯碱中的一种或多种;
    优选地,所述pH调节剂为质量分数为25%-50%的氢氧化钠水溶液。
  13. 一种三元正极材料,其特征在于,由内至外依次包括A层、B层、C层和D层,所述A层、所述B层、所述C层的孔隙率依次增大,所述D层的孔隙率最小或无孔;
    优选地,所述三元正极材料使用权利要求1-7任一项所述的三元正极材料前驱体烧制得到。
  14. 一种锂离子电池正极,其特征在于,包括权利要求13所述的三元正极材料。
  15. 一种锂离子电池,其特征在于,包括权利要求14所述的锂离子电池正极。
  16. 一种涉电设备,其特征在于,包括权利要求15所述的锂离子电池。
PCT/CN2022/098559 2022-01-27 2022-06-14 三元正极材料前驱体及其制备方法、三元正极材料、锂离子电池及正极和涉电设备 WO2023142335A1 (zh)

Priority Applications (3)

Application Number Priority Date Filing Date Title
JP2023532305A JP2024507033A (ja) 2022-01-27 2022-06-14 三元系正極材料前駆体並びにその調製方法、三元系正極材料、リチウムイオン電池、正極、電気設備
KR1020237020168A KR20230117359A (ko) 2022-01-27 2022-06-14 3원계 양극 재료 전구체 및 이의 제조 방법, 3원계 양극 재료, 리튬 이온 전지 및 양극, 및 리튬 이온 전지를 포함하는 장치
US18/467,413 US20230416110A1 (en) 2022-01-27 2023-09-14 Ternary positive electrode material precursor and preparation method thereof, ternary positive electrode material, lithium-ion battery, positive electrode, and electric-involved equipment

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CN202210101448.7 2022-01-27
CN202210101448.7A CN114744164A (zh) 2022-01-27 2022-01-27 三元正极材料前驱体及其制备方法、三元正极材料、锂离子电池及正极和涉电设备

Related Child Applications (1)

Application Number Title Priority Date Filing Date
US18/467,413 Continuation-In-Part US20230416110A1 (en) 2022-01-27 2023-09-14 Ternary positive electrode material precursor and preparation method thereof, ternary positive electrode material, lithium-ion battery, positive electrode, and electric-involved equipment

Publications (1)

Publication Number Publication Date
WO2023142335A1 true WO2023142335A1 (zh) 2023-08-03

Family

ID=82274565

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2022/098559 WO2023142335A1 (zh) 2022-01-27 2022-06-14 三元正极材料前驱体及其制备方法、三元正极材料、锂离子电池及正极和涉电设备

Country Status (5)

Country Link
US (1) US20230416110A1 (zh)
JP (1) JP2024507033A (zh)
KR (1) KR20230117359A (zh)
CN (1) CN114744164A (zh)
WO (1) WO2023142335A1 (zh)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN116873989A (zh) * 2023-09-08 2023-10-13 浙江帕瓦新能源股份有限公司 镍钴锰三元前驱体及其制备方法、正极材料、锂离子电池

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115810757B (zh) * 2023-02-09 2023-05-05 中创新航科技股份有限公司 一种正极活性材料及含有该正极活性材料的锂离子电池
CN117083247A (zh) * 2023-06-27 2023-11-17 广东邦普循环科技有限公司 一种三元材料前驱体及其制备的三元材料
CN116914129B (zh) * 2023-09-15 2024-02-13 宁德时代新能源科技股份有限公司 正极活性材料及其制备方法、正极极片、电池和用电装置

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2015072800A (ja) * 2013-10-03 2015-04-16 住友金属鉱山株式会社 非水系電解質二次電池用正極活物質とその製造方法、およびこれを用いた非水系電解質二次電池
JP2020119787A (ja) * 2019-01-24 2020-08-06 住友金属鉱山株式会社 ニッケルマンガンコバルト含有複合水酸化物およびその製造方法、リチウムイオン二次電池用正極活物質およびその製造方法、並びに、リチウムイオン二次電池
CN111653756A (zh) * 2019-03-04 2020-09-11 屏南时代新材料技术有限公司 正极活性物质前驱体、其制备方法及正极活性物质
CN112928250A (zh) * 2021-01-22 2021-06-08 厦门厦钨新能源材料股份有限公司 一种镍钴锰三元材料及其前驱体和制备方法与应用
CN114261997A (zh) * 2021-12-28 2022-04-01 广西中伟新能源科技有限公司 镍钴氢氧化物及制备方法、镍钴氧化物、锂离子电池正极材料、正极、电池及涉电设备
CN114314692A (zh) * 2021-12-28 2022-04-12 中伟新材料股份有限公司 三元正极材料前驱体及制备方法、正极材料、正极浆料、锂离子电池及正极和涉电设备

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP7012721B2 (ja) * 2016-12-02 2022-01-28 サムスン エスディアイ カンパニー,リミテッド リチウム二次電池用ニッケル系活物質前駆体、その製造方法、そこから形成されたリチウム二次電池用ニッケル系活物質、及びそれを含む正極を含むリチウム二次電池
CN113161529B (zh) * 2021-06-23 2021-09-14 湖南长远锂科股份有限公司 一种高镍正极材料及其制备方法

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2015072800A (ja) * 2013-10-03 2015-04-16 住友金属鉱山株式会社 非水系電解質二次電池用正極活物質とその製造方法、およびこれを用いた非水系電解質二次電池
JP2020119787A (ja) * 2019-01-24 2020-08-06 住友金属鉱山株式会社 ニッケルマンガンコバルト含有複合水酸化物およびその製造方法、リチウムイオン二次電池用正極活物質およびその製造方法、並びに、リチウムイオン二次電池
CN111653756A (zh) * 2019-03-04 2020-09-11 屏南时代新材料技术有限公司 正极活性物质前驱体、其制备方法及正极活性物质
CN112928250A (zh) * 2021-01-22 2021-06-08 厦门厦钨新能源材料股份有限公司 一种镍钴锰三元材料及其前驱体和制备方法与应用
CN114261997A (zh) * 2021-12-28 2022-04-01 广西中伟新能源科技有限公司 镍钴氢氧化物及制备方法、镍钴氧化物、锂离子电池正极材料、正极、电池及涉电设备
CN114314692A (zh) * 2021-12-28 2022-04-12 中伟新材料股份有限公司 三元正极材料前驱体及制备方法、正极材料、正极浆料、锂离子电池及正极和涉电设备

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN116873989A (zh) * 2023-09-08 2023-10-13 浙江帕瓦新能源股份有限公司 镍钴锰三元前驱体及其制备方法、正极材料、锂离子电池
CN116873989B (zh) * 2023-09-08 2023-12-08 浙江帕瓦新能源股份有限公司 镍钴锰三元前驱体及其制备方法、正极材料、锂离子电池

Also Published As

Publication number Publication date
JP2024507033A (ja) 2024-02-16
CN114744164A (zh) 2022-07-12
US20230416110A1 (en) 2023-12-28
KR20230117359A (ko) 2023-08-08

Similar Documents

Publication Publication Date Title
WO2023142335A1 (zh) 三元正极材料前驱体及其制备方法、三元正极材料、锂离子电池及正极和涉电设备
CN112750999B (zh) 正极材料及其制备方法和锂离子电池
CN109721109B (zh) 一种锂电池用镍钴锰三元正极材料前驱体及其制备方法和制备得到的正极材料
KR100725399B1 (ko) 코아·쉘 구조를 가지는 리튬이차전지용 양극활물질, 그를사용한 리튬이차전지 및 그 제조 방법
TWI549343B (zh) A positive electrode active material for a lithium ion battery, a positive electrode for a lithium ion battery, and a lithium ion battery
CN110993903B (zh) 一种钽改性高镍正极材料及其制备方法与应用
TWI423508B (zh) A positive electrode active material for a lithium ion battery, a positive electrode for a lithium ion battery, and a lithium ion battery
KR101450421B1 (ko) 리튬 이온 전지용 정극 활물질, 리튬 이온 전지용 정극, 및 리튬 이온 전지
JP7135856B2 (ja) ニッケルマンガン複合水酸化物とその製造方法、非水系電解質二次電池用正極活物質とその製造方法、および非水系電解質二次電池
WO2021136490A1 (zh) 一种富锂锰基材料及其制备方法和应用
CN111370690B (zh) 锂离子电池高镍正极材料、其制备方法及应用
US20230369584A1 (en) Positive electrode material, preparation method therefor and use thereof, and lithium ion battery
JP2023100694A (ja) リチウム複合酸化物
CN114597378A (zh) 一种超高镍多晶正极材料及其制备方法和应用
CN114512663A (zh) 一种无钴无锰正极材料及其制备方法与用途
CN116759525A (zh) 钠离子电池正极材料前驱体及其制备方法、钠离子电池正极材料、钠离子电池和涉电设备
US20230290942A1 (en) Solid Phase Synthesis Method of Positive Electrode Active Material of Nickel-Rich Lithium Composite Transition Metal Oxide in a Form of a Single Particle, Positive Electrode Active Material of Nickel-Rich Lithium Composite Transition Metal Oxide in a Form of a Single Particle Formed Therefrom, Positive Electrode and Lithium Secondary Battery Containing the Same
US11984590B2 (en) Positive electrode material for lithium ion battery and preparation method therefor
JP7454642B1 (ja) リチウム金属複合酸化物、リチウム二次電池用正極活物質、リチウム二次電池用正極及びリチウム二次電池
KR102629076B1 (ko) 양극 활물질 및 이를 포함하는 이차전지
RU2791251C1 (ru) Добавка к активному катодному материалу для литий-ионных аккумуляторов, способ ее получения и активный катодный композитный материал, содержащий добавку
CN117776286A (zh) 镍钴锰氢氧化物前驱体及制备方法、镍钴锰氧化物前驱体及制备方法和锂离子电池正极材料
CN116072858A (zh) 一种铌掺杂的镍钴锰铝酸锂四元材料及其制备方法和包含其的锂离子电池
CN117247056A (zh) 一种锂离子电池无钴正极材料的制备及其应用
CN114843477A (zh) 一种多晶结构的超高镍正极材料及其制备方法和应用

Legal Events

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

Ref document number: 2023532305

Country of ref document: JP

ENP Entry into the national phase

Ref document number: 20237020168

Country of ref document: KR

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: 22920990

Country of ref document: EP

Kind code of ref document: A1