CN112436121A - Composite material with core-shell structure and preparation method thereof - Google Patents

Composite material with core-shell structure and preparation method thereof Download PDF

Info

Publication number
CN112436121A
CN112436121A CN202011332318.1A CN202011332318A CN112436121A CN 112436121 A CN112436121 A CN 112436121A CN 202011332318 A CN202011332318 A CN 202011332318A CN 112436121 A CN112436121 A CN 112436121A
Authority
CN
China
Prior art keywords
lithium
nickel
core
composite material
particles
Prior art date
Legal status (The legal status 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 status listed.)
Granted
Application number
CN202011332318.1A
Other languages
Chinese (zh)
Other versions
CN112436121B (en
Inventor
杭道金
陆君
孟凡臣
肖天辉
朱灵霖
王雅苹
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Shanghai Huayi Group Corp
Original Assignee
Shanghai Huayi Group Corp
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 Shanghai Huayi Group Corp filed Critical Shanghai Huayi Group Corp
Priority to CN202011332318.1A priority Critical patent/CN112436121B/en
Publication of CN112436121A publication Critical patent/CN112436121A/en
Application granted granted Critical
Publication of CN112436121B publication Critical patent/CN112436121B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H01M4/362—Composites
    • H01M4/366—Composites as layered products
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/052—Li-accumulators
    • H01M10/0525—Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H01M4/48—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides
    • H01M4/485—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of mixed oxides or hydroxides for inserting or intercalating light metals, e.g. LiTi2O4 or LiTi2OxFy
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H01M4/48—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides
    • H01M4/50—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of manganese
    • H01M4/505—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of manganese of mixed oxides or hydroxides containing manganese for inserting or intercalating light metals, e.g. LiMn2O4 or LiMn2OxFy
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H01M4/48—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides
    • H01M4/52—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of nickel, cobalt or iron
    • H01M4/525—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of nickel, cobalt or iron of mixed oxides or hydroxides containing iron, cobalt or nickel for inserting or intercalating light metals, e.g. LiNiO2, LiCoO2 or LiCoOxFy
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/62—Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10—Energy storage using batteries

Landscapes

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

Abstract

The composite material comprises a high-nickel ternary material core and a composite material shell of a high-molecular polymer and lithium iron manganese phosphate, wherein the high-nickel ternary material is selected from lithium nickel cobalt manganese oxide, lithium nickel cobalt aluminate and lithium nickel manganese oxide or a mixture formed by two or more of the lithium nickel cobalt manganese oxide, the lithium nickel cobalt aluminate and the lithium nickel manganese oxide, wherein the molar ratio of nickel to metal except lithium is not less than 60%; the high molecular polymer is selected from acrylic acid polymers; the composite material with the core-shell structure is prepared by the following method: adding the granular high-nickel ternary material into a high molecular polymer solution to form a liquid film layer on the surface of the granules; and adding a micron-sized lithium iron manganese phosphate material, stirring, removing the solvent, and forming a coating layer on the surface of the particles.

Description

Composite material with core-shell structure and preparation method thereof
Technical Field
The invention relates to a preparation method of a coated lithium ion battery anode material, belonging to the technical field of lithium ion battery anode materials. The positive electrode material prepared by the method can lead the formed lithium ion battery to have high capacity and long cycle life.
Technical Field
In the present lithium ion battery anode materials for mass production, the high-nickel ternary material has the highest energy density and low dependence on cobalt, and is a more promising anode material. However, increasing the nickel content in the ternary material results in a decrease in the thermal stability of the material, which is manifested by a decrease in the reaction temperature with the electrolyte in the delithiated state and an increase in the heat of reaction; meanwhile, the surface alkalinity of the ternary material with higher nickel content is increased, so that the sensitivity to the environmental humidity is increased, and gel is easily generated in the mixing process.
The lithium iron manganese phosphate has the same crystal structure as the lithium iron phosphate, has the characteristics of safety, long service life and low cost, and has high cooperativity with the high-nickel ternary material in discharge voltage. By coating or mixing the lithium iron manganese phosphate and the ternary material, the advantages of the lithium iron manganese phosphate and the ternary material with high nickel content are exerted to the greatest extent, and the method is a method for improving the insufficient performance of the ternary material.
CN104300123B discloses a mixed anode material, an anode sheet using the anode material and a lithium ion battery, wherein the anode sheet is prepared by mixing lithium manganese iron phosphate or/and lithium iron phosphate and nickel cobalt manganese respectively in a slurry mixing stage. However, the simple physical mixing method cannot uniformly mix the lithium iron manganese phosphate and the ternary material, and the performance of the lithium iron manganese phosphate and the ternary material still has certain limitations.
CN109273684A reports a composite cathode material for lithium ion batteries and a preparation method thereof, in which a core material-carbon-phosphate cathode material structure is constructed to connect phosphate and a ternary material through a carbon layer, so that the combination is tighter and the conductivity of the material is more excellent. However, in the present method, a step of sintering the phosphate-carbon-containing organic-ternary material under an inert atmosphere is involved. The ternary material has stronger oxidability and is very easy to react with carbon at high temperature, so that the structure and the performance of the material are changed. This method has certain limitations.
CN107546379A discloses a method for preparing a lithium iron manganese phosphate coated ternary material by mechanical fusion. In the method, nanoscale lithium iron manganese phosphate particles are coated on the surfaces of micron-sized ternary material particles under the action of mechanical fusion. However, in the process, if the mechanical fusion strength is too low, the acting force between the lithium iron manganese phosphate particles and the ternary material is weak, and if the mechanical fusion strength is too high, the ternary material itself can be abraded and peeled off under the mechanical fusion effect, so that the surface is actually coated by the mixture of the peeled nanoscale ternary material and the lithium iron manganese phosphate, and an ideal balance point is difficult to find between the coating effect and the binding force.
CN111048760A discloses a method for preparing a lithium iron manganese phosphate coated single crystal ternary material by a physical adsorption method. The method utilizes the high surface energy of the nanoscale lithium manganese iron phosphate to make the nanoscale lithium manganese iron phosphate adsorbed on the surface of the single-crystal ternary particles. However, the preparation process of the nano-scale lithium manganese iron phosphate is complex, self agglomeration is easy to occur, and the condition that the coating layer does not fall off in the processes of homogenate coating and the like cannot be guaranteed only by means of physical adsorption. So that its practical application is limited.
There is still a need in the art for an improved method for better coating lithium manganese iron phosphate onto the surface of a high-nickel ternary material. The cathode material prepared by the method can lead the formed lithium ion battery to have high capacity and cycle life.
Disclosure of Invention
The invention aims to provide an improved method for coating lithium iron manganese phosphate on the surface of a high-nickel ternary material. The cathode material prepared by the method can lead the formed lithium ion battery to have high capacity and long cycle life.
Accordingly, one aspect of the present invention relates to a composite material having a core-shell structure, comprising a high-nickel ternary material core and a composite material shell of a high molecular polymer and lithium iron manganese phosphate,
the high nickel ternary material is selected from lithium nickel cobalt manganese oxide, lithium nickel cobalt aluminate, lithium nickel manganese oxide or a mixture of two or more of the nickel cobalt manganese oxide, the lithium nickel cobalt aluminate and the lithium nickel manganese oxide, wherein the nickel accounts for not less than 60% of the molar weight of transition metal except lithium;
the high molecular polymer includes an acrylic polymer;
in the composite material shell, lithium iron manganese phosphate particles are dispersed on the outer surface of a high molecular polymer substrate to form a lithium iron manganese phosphate particle outer cladding layer.
Another aspect of the present invention relates to a method for manufacturing a composite material having a core-shell structure, which includes a high-nickel ternary material core and a composite material shell of a high molecular polymer and lithium manganese iron phosphate.
The high nickel ternary material is selected from nickel cobalt lithium manganate, nickel cobalt lithium aluminate, nickel lithium manganate or a mixture of two or more of the nickel cobalt lithium manganate, the nickel cobalt lithium aluminate and the nickel lithium manganate account for not less than 60% of the molar weight of transition metal except lithium;
the high molecular polymer includes an acrylic polymer;
the method comprises the following steps:
adding the granular high-nickel ternary material into a high molecular polymer solution to form a liquid film layer on the surface of the granules; and
adding a micron-sized lithium iron manganese phosphate material, stirring, removing the solvent, and forming a coating layer on the surface of the particles.
Drawings
The invention is further described below with reference to the accompanying drawings. In the drawings:
FIG. 1 is an SEM photograph of a sample of example 2;
figure 2 is the EDS elemental surface scan results for the example 2 sample.
Detailed Description
In the present invention, the term "acrylic polymer" includes polymers comprising (meth) acrylic acid, (meth) acrylate, (meth) acrylamide, (meth) acrylonitrile monomer units, including homopolymers, copolymers or mixtures thereof.
The term (meth) acrylic acid includes acrylic acid and methacrylic acid. By analogy, (meth) acrylates include acrylates and methacrylates, for example.
In one embodiment of the present invention, the (meth) acrylate comprises (meth) acrylic acid C1-10Alkyl esters, such as Methyl Methacrylate (MMA), Ethyl Methacrylate (EMA), Butyl Methacrylate (BMA), ethylhexyl methacrylate (EHMA), Lauryl Methacrylate (LMA), hydroxyethyl methacrylate (HEMA), Methyl Acrylate (MA), Ethyl Acrylate (EA), Butyl Acrylate (BA), ethylhexyl acrylate (EHA), and hydroxyethyl acrylate (HEA), as well as other esters of AA or MAA, such as alkyl esters, hydroxyalkyl esters, and aminoalkyl esters; a phosphoalkyl (meth) acrylate.
In one embodiment of the present invention, the (meth) acrylate salt comprises an ammonium (meth) acrylate salt.
In one embodiment of the invention, the comonomer used to form the acrylic polymer is selected from C2-10Such as ethylene, propylene, butylene, styrene, and the like.
In one embodiment of the present invention, the amount of the monomer units derived from (meth) acrylic acid, (meth) acrylate, (meth) acrylamide, (meth) acrylonitrile in the acrylic polymer is not less than 40%, preferably not less than 60%, more preferably not less than 80%, preferably not less than 95%, for example, 100% by mole.
When the acrylic polymer of the present invention is in the form of an emulsion, the particle size distribution may be monomodal or bimodal, see, for example, U.S. patent No. 6,818,697. Polymers prepared by emulsion polymerization or other techniques known in the art may be used. The progress of the Emulsion Polymerization is discussed in detail in Emulsion Polymerization (Wiley, 1975) of D.C. Black. The polymers of the present invention may be prepared as aqueous dispersions of polymer particles using conventional emulsion polymerization techniques. The progress of emulsion polymerization is also discussed in H.Warson, The Applications of Synthetic Resin Emulsions, Chapter Ernest Benn Ltd, London 1972.
The molecular weight of the "acrylic polymer" of the present invention is 2000-100000, preferably 4000-50000.
The composite material with the core-shell structure comprises a core formed by a high-nickel ternary material and a shell formed by a composite material of a high polymer and lithium iron manganese phosphate.
1. High nickel ternary material core
The high nickel ternary material is selected from nickel cobalt lithium manganate, nickel cobalt lithium aluminate, nickel lithium manganate or a mixture of two or more of the nickel cobalt lithium aluminate, the amount of nickel is not less than 60%, preferably not less than 62%, more preferably not less than 65%, and preferably not less than 68% by mole of metals other than lithium.
In one embodiment of the invention, the nickel is present in an amount of 60 to 90%, preferably 62 to 85%, more preferably 65 to 80%, preferably 68 to 75%, based on the molar amount of the metal other than lithium.
The grain structure of the high-nickel ternary material can be single crystal primary grains or polycrystalline secondary grains.
In one example of the invention, the high nickel ternary material is lithium nickel cobalt manganese oxide, wherein the ratio of Ni to Co to Mn is in the range of 3:1:1 to 9:0.5:0.5, such as 6:2:2, 7:1.5:1.5, 8:1: 1.
In one embodiment of the invention, the nickel cobalt manganese ternary material has alpha-NaFeO2A layered crystal structure belonging to the R3m space and having the chemical formula LiNi1-x-yCoxMnyO2Wherein x is more than 0 and less than 1, y is more than 0 and less than 1, and x + y<0.4。
In one embodiment of the invention, the high nickel ternary material has a specific surface area of 0.2-3m2/g。
In one embodiment of the invention, the high nickel ternary material is a nickel cobalt lithium aluminate (NCA) material having the formula LiNixCoyAlzO2，x+y+z＝1，x>0.6. In one embodiment of the present invention, Ni: co: ranges of Al include and are not limited to 7:1.5: 1.5; 8:1: 1; 0.85:0.1:0.05.
In one embodiment of the invention, the high nickel ternary material is selected from high voltage lithium nickel manganese oxide LiNi1.5Mn0.5O4。
In one embodiment of the invention, the secondary particles D of the high nickel ternary material50Is 5 to 50 microns, preferably 8 to 45 microns, more preferably 10 to 40 microns, preferably 12 to 35 microns, preferably 14 to 30 microns.
The method for producing the high nickel ternary material to be used is not particularly limited, and any known method for producing the high nickel ternary material or a commercially available high nickel ternary material may be used.
2. Composite material shell of high molecular polymer and lithium manganese iron phosphate
The lithium iron manganese phosphate suitable for use in the present invention is not particularly limited and may be a conventional lithium iron manganese phosphate material known in the art. In one embodiment of the present invention, the manganese content of the lithium manganese iron phosphate is not less than 55%, preferably not less than 58%, more preferably not less than 60%, and preferably not less than 62% in terms of the molar amount of the transition metal other than lithium.
In one embodiment of the present invention, the manganese content of the lithium manganese iron phosphate is 55 to 90%, preferably 58 to 85%, more preferably 60 to 80%, and preferably 62 to 75% by mole of the transition metal other than lithium.
In one embodiment of the present invention, the lithium iron manganese phosphate has a structural formula of Li1+aMn1-b-cFebMcPO4Wherein a is more than or equal to 0.02 and less than or equal to 0.07, b + c is more than or equal to 0.1 and less than or equal to 0.45, c is more than or equal to 0 and less than or equal to 0.05, and M comprises Mg.
In one embodiment of the present invention, the lithium iron manganese phosphate material further contains carbon, and the carbon element accounts for 1.0-3.0%, preferably 1.2-2.8%, and preferably 1.5-2.5% of the total mass of the lithium iron manganese phosphate.
In one embodiment of the present invention, D of the lithium iron manganese phosphate secondary particles50The particle size is 0.5 to 3 microns, preferably 0.7 to 2 microns, more preferably 0.8 to 1.5 microns.
In one embodiment of the invention, the lithium iron manganese phosphate material has a particle structure with a specific surface area of 10-40m2Per g, preferably 12 to 35m2/g。
In one embodiment of the invention, the lithium iron manganese phosphate has an olivine crystal structure and a chemical formula of LiMnzFe1-zPO4Wherein z is more than or equal to 0.55 and less than or equal to 1, and the specific surface area is 10-40m2(ii)/g; preferably, z is 0.6-0.8, and the specific surface area is 12-30m2/g。
The high molecular polymer suitable for the present invention includes acrylic polymers.
In one example of the present invention, the composite material with the core-shell structure includes a high-nickel ternary material core and a composite material shell of a high polymer and lithium manganese iron phosphate, the composite material shell uniformly covers the high-nickel ternary material core, and in the composite material shell, lithium manganese iron phosphate particles are dispersed on the surface of a high polymer matrix to form an outer cladding layer of the lithium manganese iron phosphate particles.
In the present invention, the term "outer coating of lithium iron manganese phosphate particles" means that the lithium iron manganese phosphate particles in the composite shell have a non-uniform radial distribution with a higher concentration on the outer surface of the shell than on the inner surface of the shell near the core. In one example of the present invention, the lithium iron manganese phosphate particles have a distribution in the shell such that a portion of each particle is exposed to the outside of a matrix layer formed of a high molecular polymer.
The manufacturing method of the composite material with the core-shell structure comprises the following steps:
p-1 forms a liquid film layer on the surface of the high-nickel ternary material particles
The method for forming the liquid film layer on the surface of the high nickel ternary material particle is not particularly limited and may be a conventional method known in the art. In one embodiment of the invention, the high-nickel ternary material particles are added into a high-molecular polymer solution under the stirring action, and a liquid film layer is formed on the surfaces of the particles. In one embodiment of the present invention, the liquid film layer has a tackiness.
In one embodiment of the present invention, the solution of the high molecular weight polymer is a solution of the acrylic polymer of the present invention in a solvent, and the solvent may be an aqueous solution, an aqueous emulsion or an oily solution (a solution of an organic solvent such as ethanol, acetone, DMAc, etc.), preferably an aqueous solution, depending on the oil-water compatibility of the acrylic polymer. In addition to the high molecular weight polymers, compatibilizers such as polyvinyl alcohol and polyvinyl pyrrolidone of various specifications can be selected as additives to improve the adhesion of polyacrylic acid polymers.
In one embodiment of the present invention, the concentration of the high molecular weight polymer solution is between 20 and 80% wt, preferably between 30 and 70% wt, and more preferably between 40 and 60% wt; the room temperature viscosity is between 100-100000cps, preferably 500-50000cps, more preferably 3000-30000 cps.
The amount of the high nickel ternary material particles and the high molecular polymer to be used is not particularly limited as long as the amount of the high molecular polymer and the concentration of the high molecular polymer solution are sufficient to form a liquid film layer on the surface of the high nickel ternary material particles and the liquid film layer is sufficient to form a coating layer in a subsequent step.
In one embodiment of the present invention, the effective mass ratio of the high-nickel ternary material particles to the high-molecular polymer is 95:5 to 99.9:0.1, preferably 98:2 to 99.8:0.2, and most preferably 99:1 to 99.6: 0.4.
The stirring conditions suitable for the method of the present invention are not particularly limited and may be conventional stirring conditions known in the art. In one embodiment of the invention, a double-cone drying mixer, a high-speed mixer, a planetary mixer and a horizontal mixer are used for stirring; preferably, a high-speed mixer and a double-cone drying mixer are adopted for stirring. In one embodiment of the invention, the material occupies 5-50% of the cavity volume during stirring, preferably 15-40%; the stirring time is between 5 minutes and 2 hours, preferably between 30 minutes and 1 hour.
P-2 forming a coating layer
The method for forming the coating layer comprises the steps of mixing the system with a micron-sized lithium iron manganese phosphate material, continuously stirring, and properly heating and evaporating the solvent.
The mixing method of the high-nickel ternary material particles with the liquid film layer on the surface and the micron-sized lithium iron manganese phosphate material in forming the coating layer is not particularly limited, and may be a conventional method known in the art. For example, the micron-sized lithium iron manganese phosphate material can be added into high-nickel ternary material particles with a liquid film layer, and the mixture is stirred and mixed.
The amount of lithium manganese iron phosphate added in forming the coating layer is not particularly limited as long as it is sufficient to form the coating layer and the resulting coated product has improved properties. In one embodiment of the present invention, the amount of lithium iron manganese phosphate added is such that the effective mass ratio between the lithium iron manganese phosphate and the high-nickel ternary material and the high-molecular polymer in the system is between 30:70 and 1:99, preferably between 20:80 and 3:97, and more preferably between 15:85 and 5: 95.
The stirring conditions used in forming the coating layer are not particularly limited and may be conventional stirring conditions known in the art. In one embodiment of the present invention, the stirring is performed by a high-speed mixer, a high-speed mixing granulator, a double-cone dry mixer, a planetary mixer, a horizontal mixer, preferably a high-speed mixer, a high-speed mixing granulator, or a double-cone dry mixer.
In one embodiment of the invention, the stirring time is between 5 minutes and 2 hours, preferably between 30 minutes and 1 hour.
The temperature for heating to evaporate the solvent is not particularly limited as long as the temperature is favorable for evaporating the solvent and does not adversely affect the product. In one embodiment of the invention, the temperature of evaporation is between 40 and 80 ℃, preferably 60 to 70 ℃.
Drying P-3 to obtain the final product
And (3) removing residual moisture and solvent from the product (or powder) obtained by evaporation to obtain the final product. Suitable methods for removing water and solvent are not particularly limited and may be any conventional methods known in the art. In one embodiment of the invention, the water and solvent are removed by heating under vacuum. In one embodiment of the present invention, the drying equipment used is a forced air oven, a vacuum oven, a belt drying kiln, etc., which is preferably matched with the amount of the material; the degree of vacuum for drying is between 0 and-1.0 Bar, preferably between 0 and-0.6 Bar; drying at 60-150 deg.C, preferably 80-120 deg.C; drying time, between 2 hours and 48 hours, preferably 4-24 hours, more preferably 6 to 12 hours; the drying atmosphere is dry air or nitrogen, preferably inert gas.
The invention has the advantages that: the surface high molecular polymer can play a role in adhesion, coating and lithium conduction, can improve the binding force of the core shell, enables the coating to be more uniform, solves the problems of residual alkali on the surface of the high-nickel ternary material and side reaction of electrolyte, helps the migration of lithium ions, and improves the rate capability; the surface lithium iron manganese phosphate secondary particles can buffer the damage of the rolling process of the pole piece to the ternary particles, and the cycle life of the material is prolonged.
Examples
The present invention will be described in detail with reference to examples. These embodiments are not intended to limit the present invention, and structural, methodological, or functional changes made by those skilled in the art according to these embodiments are included in the scope of the present invention.
The electrochemical performance test method of the obtained product comprises the following steps:
according to the active substance: conductive agent: binder 94:3:3 by weight with NMP as solvent, active material, conductive carbon black and binder mixed at-12 mg/cm2The areal density of (2) was coated on one side on an aluminum foil and dried in vacuo. And rolling the dried pole piece, cutting the pole piece into a circle, taking a lithium piece as a counter electrode, taking a solution of lithium hexaflourophosphate with the concentration of 1.0M and DMC (EC) ═ 1:1(V/V) as an electrolyte, and isolating the positive electrode and the negative electrode by a PP diaphragm with the thickness of 20 micrometers to assemble the CR2025 button cell. The rate test was performed according to the following conditions:
and (3) testing temperature: 25 +/-2 ℃;
voltage range: 3.0-4.3V;
the test flow comprises the following steps:
charging: charging at 180mA/g, and stopping at 1.5mA/g constant voltage after 4.3V;
discharging: discharging at a current of 0.1 deg.C and stopping at 3.0V according to 18mA/g active substance;
repeating the charging step, and carrying out a multiplying power test according to the discharging currents of 1C and 3C;
the charging step is repeated, and the cycle is 100 cycles according to the discharge current of 1C.
Example 1
Single crystal 622 material (LiNi) was prepared according to the method disclosed in CN1063289210.6Co0.2Mn0.2O2) 100g of the single crystal 622 material is added into a high-speed mixing granulator, 17.5g of acetone solution of polyacrylic acid (which accounts for 50% of the whole monomer molar ratio) with the solid content of 30% and the room temperature viscosity of 1000 cps-ethyl acrylate copolymer (which accounts for 5% of the total mass of the copolymer) is added, the high-speed mixing granulator is closed and started, the rotating speed is set to be 1000rpm, and the mixing time is 5 minutes, so that the high-molecular polymer forms a uniform adhesion layer on the surfaces of the single crystal 622 particles. In this process, the material occupies about 5% of the volume of the chamber.
Stopping the high-speed mixing granulator, weighing 43g (accounting for about 30 percent of the total mass) of manganese iron phosphate with the Mn/Fe ratio of 55/45, the carbon content of 1.1 percent by weight and the secondary particle D50 of 0.7 micron, putting the weighed materials into the granulator, sealing the granulator, setting the rotating speed to be 1500rpm, and mixing and granulating for 5 minutes. In the process, the temperature of the material automatically rises to around 40 ℃ due to the heat generated by the operation of the equipment. After the completion, the material is discharged from the discharge hole and transferred into a glass beaker.
The materials in the glass beaker are placed in a vacuum oven, the gas is replaced by nitrogen for 2 times, and then the temperature is set to be 100 ℃, the vacuum degree is set to be 0.3Bar, and the materials are dried for 24 hours.
After the product is taken out, the button half cell is assembled according to the battery assembly mode, and the performance of the cell is tested by taking the single crystal 622 as a control sample. The results are shown in Table 1.
Table 1 results of the test for withholding of the sample and reference sample of example 1
Figure BDA0002796176740000081
The test results show that after the lithium iron phosphate/acrylic acid copolymer-containing shell is coated, the prepared lithium ion battery has obviously improved capacity of 1C gram, 3C gram and cycle life.
Example 2
3000g of polycrystalline 811 material (LiNi) was taken0.8Co0.1Mn0.1O2) Adding the mixture into a high-speed mixer, adding 153g of ethanol solution of polyacrylic acid (80% of the whole monomer molar ratio) with the solid content of 40% and the room-temperature viscosity of 27000 cps-butyl acrylate copolymer (about 2% of the total mass of the copolymer), sealing and starting the high-speed mixer, setting the rotating speed to be 1500rpm, and mixing for 15 minutes to form a relatively uniform adhesion layer on the surfaces of the polycrystal 811 particles. In this process, the material occupies about 15% of the volume of the chamber.
Stopping the high-speed mixer, weighing 765g (about 20 percent of the total mass) of lithium manganese iron phosphate with the Mn/Fe ratio of 60/40, the carbon content of 1.5 percent by weight and the secondary particle D50 particle size of 0.8 micron, putting the 765g of lithium manganese iron phosphate into the mixer, sealing the high-speed mixer, setting the rotating speed to 2000rpm, and mixing and granulating for 15 minutes. During this process, the temperature of the material automatically rises to around 55 ℃ due to the heat generated by the operation of the equipment. And after the completion, discharging the material from the discharge hole, and transferring the material into a sample pot.
And (3) placing the materials in the sample bowl in a vacuum oven, replacing gas with nitrogen for 2 times, setting the temperature at 100 ℃ and the vacuum degree at 0.5Bar, drying for 24 hours, and replacing and exhausting the nitrogen for 2 times in the drying process.
After the product was taken out, SEM analysis was performed on the product, and the results are shown in FIG. 1. The results of cross-sectional analysis of the elements are shown in FIG. 2.
The button half cells were assembled in the manner described above for cell assembly, and cell performance was tested using poly 811 as a control. The results are shown in Table 2.
Table 2 results of testing the samples and reference samples of example 2
Figure BDA0002796176740000091
Example 3
30g of polycrystalline lithium nickel cobalt aluminate NCA80-15-5 material is added into a mixing tank of a planetary mixer, 1.1g of aqueous solution of 40% solid content, 48000cps room temperature viscosity (polymer accounting for 1.5% of the total mass) and polyethylene glycol 400 (content: 10%) is added, the mixer is closed and started, the self-transmission speed is set to 800rpm, the mixing time is 1 minute, the self-transmission speed is set to 3000rpm, and the mixing is carried out for 5 minutes, so that the high molecules form a uniform attachment layer on the surfaces of the polycrystalline lithium nickel cobalt aluminate particles. In this process, the material occupies about 15% of the volume of the chamber.
After the materials are mixed, the mixing tank is taken out, 5.4g (about 15% of the total mass) of manganese lithium iron phosphate with the Mn/Fe ratio of 70/30, the carbon content of 2.0 wt% and the secondary particle D50 particle size of 2.3 microns is weighed and put into the mixing tank, after the mixing tank is closed, the initial rotating speed is set to 800rpm, the mixing is carried out for 1 minute, the rotating speed is set to 3000rpm, and the mixing is carried out for 5 minutes. In the process, the temperature of the material automatically rises to around 43 ℃ due to the heat generated by the operation of the equipment. And after the completion, taking the materials out of the mixing tank, and transferring the materials into a glass beaker.
The material in the glass beaker is placed in a vacuum oven, the gas is replaced by nitrogen for 2 times, and then the temperature is set to be 150 ℃, the vacuum degree is set to be 1.0Bar, and the material is dried for 2 hours.
After the product is taken out, the button half cell is assembled according to the battery assembly mode, and the performance of the button half cell is tested by taking the polycrystal NCA80-15-5 as a comparison sample. The results are shown in Table 3.
Table 3 test results for the samples and reference samples of example 3
Figure BDA0002796176740000101
Example 4
Adding 2500g of polycrystalline lithium nickel manganese oxide NM70-30 material into a double-cone mixer with a heating function, adding 210g of aqueous solution of ammonium polymethacrylate (the polymer accounts for about 4% of the total mass) with the solid content of 50%, the room temperature viscosity of 80000cps and a compatilizer polyethylene glycol 1200 (the content of 20%), sealing and starting the mixer, setting the temperature at 40 ℃, the rotating speed at 60rpm, and mixing for 30 minutes to form a uniform adhesion layer on the surfaces of polycrystalline lithium nickel manganese oxide particles by high molecules. In this process, the material occupies about 35% of the volume of the chamber.
After the mixing is finished, 290g (about 10 percent of total mass) of lithium manganese iron phosphate with the Mn/Fe ratio of 75-25, the carbon content of 2.5 percent by weight and the secondary particle D50 of 1.8 microns is weighed and put into the double-cone mixer, after the double-cone mixer is closed, the initial rotating speed is set to be 120rpm, and the mixture is mixed for 30 minutes. During this process, the temperature of the mass was maintained around 80 ℃. After the completion, the material was taken out of the mixer and transferred to a sample bowl.
And (3) placing the materials in the sample pot in a blast oven with an environment dew point of-30 ℃, setting the temperature to be 80 ℃, and drying for 12 hours.
And (3) after the product is taken out, assembling the product into a button half cell according to the cell assembly mode, and testing the cell performance by taking the polycrystalline lithium nickel manganese oxide NM70-30 as a comparison sample. The results are shown in Table 4.
Table 4 test results for the samples and the reference of example 4
Figure BDA0002796176740000111
Example 5
3000g of polycrystalline lithium nickel manganese oxide NM70-30 material is taken and added into a double-cone mixer with a heating function, 252g of aqueous solution of polymethacrylic acid (polymer accounts for about 4% of the total mass) with solid content of 50%, room temperature viscosity of 80000cps and a compatilizer polyvinylpyrrolidone K10 (content of 5%) is added, the mixer is closed and started, the temperature is set to be 60 ℃, the rotating speed is 60rpm, and the mixing time is 60 minutes, so that a uniform adhesion layer is formed on the surfaces of polycrystalline lithium nickel manganese oxide particles by high molecules. In this process, the material occupies about 42% of the volume of the chamber.
And after the material mixing is finished, taking the material out of the double-cone mixer and putting the material into the high-speed mixer. Weighing the Mn/Fe ratio of 80: and (2) 166g (about 5% of the total mass) of lithium iron manganese phosphate with the carbon content of 3.2 wt% and the secondary particle D50 particle size of 1.2 microns is put into a high-speed mixer, the mixer is closed, the initial rotating speed is set to 900rpm, after 15 minutes of mixing, the wall-sticking material is properly stirred by a silica gel shovel, and then the mixing is carried out for 15 minutes, and the steps are repeated for several times and are mixed for 60 minutes. After the completion, the material was taken out of the mixer and transferred to a sample bowl.
And (3) placing the materials in the sample pot in a blast oven with an environmental dew point of-30 ℃, setting the temperature to be 80 ℃, and drying for 48 hours.
And (3) after the product is taken out, assembling the product into a button half cell according to the cell assembly mode, and testing the cell performance by taking the polycrystalline lithium nickel manganese oxide NM80-20 as a comparison sample. The results are shown in Table 5. .
Table 5 test results for the samples and the reference of example 5
Figure BDA0002796176740000112
Example 6
5000g of polycrystalline nickel cobalt lithium manganate NCM88-6-6 material is taken and added into a high-speed mixer, 102g of aqueous solution of 50% of solid content, 30000cps of room temperature viscosity (the polymer accounts for about 1% of the total mass) and 1500% of compatilizer polyacrylic acid (the content is 10%) is added, the high-speed mixer is closed and started, the rotating speed is set to be 1500rpm, and the mixing time is 60 minutes, so that the high molecules form a uniform adhesion layer on the surfaces of polycrystalline nickel lithium manganate particles. In this process, the material occupies about 40% of the volume of the chamber.
After the mixing is finished, weighing the Mn/Fe/Mg ratio as 75: 20: 150g (about 3% of the total mass) of lithium iron manganese phosphate with the carbon content of 2.3 wt% and the secondary particle D50 particle size of 1.0 micron is put into a high-speed mixer, and after the mixer is closed, the initial rotating speed is set to 1500rpm, the mixture is mixed for 15 minutes and the mixture is mixed for 60 minutes. After completion, the material was discharged from the mixer and transferred to a sample bowl.
And (3) placing the materials in the sample pot in a blast oven with an environment dew point of-30 ℃, setting the temperature to be 80 ℃, and drying for 24 hours.
And (3) after the product is taken out, assembling the product into a button half cell according to the cell assembly mode, and testing the cell performance by taking the polycrystalline lithium nickel cobalt manganese oxide NCM88-6-6 as a comparison sample. The results are shown in Table 6.
Table 6 test results for the samples and the reference samples of example 6
Figure BDA0002796176740000121
Example 7
3000g of polycrystal 811 material is taken and added into a double-cone drying mixer, 26g of aqueous solution of polymethacrylic acid (accounting for 80 percent of the whole monomer molar ratio) with the solid content of 70 percent and the room temperature viscosity of 4000cps and hydroxyethyl acrylate copolymer (accounting for 0.6 percent of the total mass of the copolymer) is added, the mixer is closed and started, the temperature is set to be 60 ℃, the rotating speed is set to be 60rpm, and the mixing time is set to be 60 minutes, so that the high polymer forms a uniform attaching layer on the surfaces of the polycrystal 811 particles. In this process, the material occupies about 35% of the volume of the chamber.
Stopping the high-speed mixer, and weighing the Mn/Fe ratio of 75: 25, 95g (about 3% of the total mass) of lithium iron manganese phosphate with a carbon content of 2.2 wt% and a secondary particle size of D50 of 1.2 μm was put into a mixer, and after the double-cone mixer was closed, the rotation speed was set at 60rpm, and the mixture was granulated for 60 minutes. During this process, the temperature of the mass was kept around 60 ℃. After the completion, the material was discharged from the discharge port and transferred to a sample pot.
And (3) placing the materials in the sample pot in a blast oven with an environment dew point of-30 ℃, setting the temperature to be 80 ℃, and drying for 24 hours.
After the product is taken out, the button half cell is assembled according to the battery assembly mode, and the performance of the cell is tested by taking the polycrystal 811 as a comparison sample. The results are shown in Table 7.
Table 7 test results for the samples and reference samples of example 7
Figure BDA0002796176740000131
Example 8
3000g of polycrystal 811 material is taken and added into a double-cone drying mixer, 30.5g of aqueous solution of polymethacrylic acid (accounting for 75 percent of the whole monomer mol ratio) with the solid content of 70 percent and the room temperature viscosity of 4000cps and methyl methacrylate copolymer (accounting for about 0.8 percent of the whole mass of the copolymer) is added, the mixer is closed and started, the temperature is set to be 60 ℃, the rotating speed is set to be 60rpm, and the mixing time is set to be 60 minutes, so that the high polymer forms a relatively uniform attachment layer on the surfaces of the polycrystal 811 particles. In this process, the material occupies about 35% of the volume of the chamber.
Stopping the high-speed mixer, weighing 159g (about 5 percent of total mass) of the lithium iron manganese phosphate with the Mn/Fe ratio of 75-25, the carbon content of 2.2 percent by weight and the secondary particle D50 with the particle size of 1.2 microns, putting the weighed materials into the mixer, sealing the double-cone mixer, setting the rotating speed to be 60rpm, and mixing and granulating for 60 minutes. During this process, the temperature of the mass was kept around 60 ℃. After the completion, the material was discharged from the discharge port and transferred to a sample pot.
And (3) placing the materials in the sample pot in a blast oven with an environment dew point of-30 ℃, setting the temperature to be 80 ℃, and drying for 24 hours.
After the product is taken out, the button half cell is assembled according to the battery assembly mode, and the performance of the cell is tested by taking the polycrystal 811 as a comparison sample. The results are shown in Table 8.
Table 8 test results for the samples and reference samples of example 8
Figure BDA0002796176740000132
Example 9
3000g of polycrystal 811 material is taken and added into a double-cone drying mixer, 73g of aqueous solution of ammonium polyacrylate (the polymer accounts for about 1.2 percent of the total mass) with the solid content of 50 percent and the room temperature viscosity of 4500cps is added, the mixer is closed and started, the temperature is set at 60 ℃, the rotating speed is 60rpm, and the mixing time is 60 minutes, so that the high polymer forms a uniform adhesive layer on the surfaces of the polycrystal 811 particles. In this process, the material occupies about 35% of the volume of the chamber.
Stopping the high-speed mixer, weighing 337g (about 10% of total mass) of manganese iron phosphate with Mn/Fe ratio of 75-25, carbon content of 2.2 wt and secondary particle D50 with particle size of 1.2 microns, putting into the mixer, sealing the double-cone mixer, setting the rotating speed at 60rpm, and mixing and granulating for 120 minutes. During this process, the temperature of the mass was kept around 60 ℃. After the completion, the material was discharged from the discharge port and transferred to a sample pot.
And (3) placing the materials in the sample pot in a blast oven with an environment dew point of-30 ℃, setting the temperature to be 80 ℃, and drying for 24 hours.
After the product is taken out, the button half cell is assembled according to the battery assembly mode, and the performance of the cell is tested by taking the polycrystal 811 as a comparison sample. The results are shown in Table 9.
Table 9 results of testing the samples and reference samples of example 9
Figure BDA0002796176740000141
Example 10
3000g of polycrystal 811 material is taken and added into a double-cone drying mixer, 104g of aqueous solution of ammonium polymethacrylate (polymer accounts for about 1.7 percent of the total mass) with the solid content of 50 percent and the room temperature viscosity of 7000cps is added, the mixer is closed and started, the temperature is set at 60 ℃, the rotating speed is 60rpm, and the mixing time is 90 minutes, so that the high molecules form a uniform adhesive layer on the surfaces of the polycrystal 811 particles. In this process, the material occupies about 35% of the volume of the chamber.
And (3) stopping the high-speed mixer, weighing 540g (about 15% of total mass) of lithium manganese iron phosphate with the Mn/Fe ratio of 75-25, the carbon content of 2.2 wt and the secondary particle D50 of 1.2 microns, putting the weighed materials into the mixer, sealing the double-cone mixer, setting the rotating speed to be 60rpm, and mixing and granulating for 120 minutes. During this process, the temperature of the mass was kept around 60 ℃. After the completion, the material was discharged from the discharge port and transferred to a sample pot.
And (3) placing the materials in the sample pot in a blast oven with an environment dew point of-30 ℃, setting the temperature to be 80 ℃, and drying for 24 hours.
After the product is taken out, the button half cell is assembled according to the battery assembly mode, and the performance of the cell is tested by taking the polycrystal 811 as a comparison sample. The results are shown in Table 10.
TABLE 10 test results for the samples and reference samples of example 10
Figure BDA0002796176740000151
Comparative example 1
Using the method of example 4 of CN107546379A, a mixture of 43gMn/Fe 55/45, 1.1 wt% carbon, lithium manganese iron phosphate with secondary particle D50 particle size of 0.7 μm, 4g polyacrylic acid (50% of the overall monomer mole ratio), ethyl acrylate copolymer (approximately 5% of the total mass of the copolymer), and 100g single crystal 622 material (LiNi)0.6Co0.2Mn0.2O2) The mechanical fusion coating is carried out in a mechanical fusion machine with the cabin volume of 0.3 liter.
And (4) after the product is taken out, assembling the product into a button half cell according to the cell assembling mode, and testing the cell performance. The results are shown in Table 1 a.
TABLE 11a samples of comparative example 1 and test results of example 1
Figure BDA0002796176740000152
Comparative example 2
The procedure of example 1 was repeated, but PVDF was used as the high molecular polymer. The method specifically comprises the following steps:
single crystal 622 material (LiNi) was prepared according to the method disclosed in CN1063289210.6Co0.2Mn0.2O2) 100g of the single crystal 622 material is added into a high-speed mixing granulator, and then the solid content is 7 percentAnd (3) sealing 75g of PVDF N-methylpyrrolidone solution, starting a high-speed mixing granulator at a set rotating speed of 1000rpm for 5 minutes to form a uniform adhesion layer on the surfaces of the single crystal 622 particles by the high-molecular polymer. In this process, the material occupies about 6% of the volume of the chamber.
Stopping the high-speed mixing granulator, weighing 43g (accounting for about 30 percent of the total mass) of manganese iron phosphate with the Mn/Fe ratio of 55/45, the carbon content of 1.1 percent by weight and the secondary particle D50 of 0.7 micron, putting the weighed materials into the granulator, sealing the granulator, setting the rotating speed to be 1500rpm, and mixing and granulating for 5 minutes. In the process, the temperature of the material automatically rises to around 40 ℃ due to the heat generated by the operation of the equipment. After the completion, the material is discharged from the discharge hole and transferred into a glass beaker.
The materials in the glass beaker are placed in a vacuum oven, the gas is replaced by nitrogen for 2 times, and then the temperature is set to be 100 ℃, the vacuum degree is set to be 0.3Bar, and the materials are dried for 24 hours.
And (4) after the product is taken out, assembling the product into a button half cell according to the cell assembling mode, and testing the cell performance. The results are shown in Table 1 b.
TABLE 1b samples of COMPARATIVE EXAMPLE 2 and results of the electrical testing of the samples of EXAMPLE 1
Figure BDA0002796176740000161

Claims (10)

1. A composite material with a core-shell structure comprises a high-nickel ternary material core and a composite material shell of a high molecular polymer and lithium manganese iron phosphate,
the high-nickel ternary material is selected from nickel cobalt lithium manganate, nickel cobalt lithium aluminate, nickel lithium manganate or a mixture of two or more of the nickel cobalt lithium aluminate and the nickel lithium manganate, and the nickel content in the high-nickel ternary material is not lower than 60% in terms of the mol of transition metal except lithium;
the high molecular polymer is selected from acrylic polymers;
in the composite material shell, lithium iron manganese phosphate particles are dispersed on the outer surface of a high molecular polymer substrate to form a lithium iron manganese phosphate particle outer cladding layer.
2. The composite material with a core-shell structure according to claim 1, wherein the high nickel ternary material is lithium nickel cobalt manganese oxide, wherein the ratio of Ni to Co to Mn is in the range of 3:1:1 to 9:0.5: 0.5; or the nickel-cobalt-manganese ternary material has alpha-NaFeO2A layered crystal structure belonging to the R3m space and having the chemical formula LiNi1-x-yCoxMnyO2Wherein x is more than 0 and less than 1, y is more than 0 and less than 1, and x + y<0.4, the specific surface area is 0.2-3m2/g。
3. The composite material with core-shell structure of claim 1, wherein the high nickel ternary material is a nickel cobalt lithium aluminate material with a chemical formula of LiNixCoyAlzO2，x+y+z＝1，x>0.6。
4. Composite material with a core-shell structure according to any of claims 1 to 3, characterised in that the secondary particles D of the high-nickel ternary material50Is 5 to 50 microns, preferably 8 to 45 microns, more preferably 10 to 40 microns, preferably 12 to 35 microns, preferably 14 to 30 microns.
5. The composite material with a core-shell structure according to any one of claims 1 to 3, wherein the manganese in the lithium iron manganese phosphate accounts for not less than 55%, preferably not less than 58%, more preferably not less than 60%, and preferably not less than 62% of the molar ratio of the transition metal.
6. The composite material having a core-shell structure according to any one of claims 1 to 3, wherein the lithium iron manganese phosphate particles in the composite shell have a non-uniform radial distribution with a higher concentration on the outer surface of the shell than on the inner surface of the shell near the core; preferably, the lithium iron manganese phosphate has a distribution in the shell such that a part of each lithium iron manganese phosphate particle is exposed to the outside of the matrix layer formed of the high molecular polymer.
7. Composite material with a core-shell structure according to any of claims 1-3, characterised in that the molecular weight of the acrylic polymer is 2000-100000, preferably 4000-50000.
8. Method for manufacturing a composite material with a core-shell structure according to any of claims 1 to 7, comprising the following steps:
mixing the granular high-nickel ternary material particles with a high molecular polymer solution to form a liquid film layer on the surfaces of the particles; and
and mixing the obtained particles with the liquid film layer with a micron-sized lithium iron manganese phosphate material, stirring, removing the solvent, and forming a coating layer on the surface of the particles.
9. The method according to claim 8, wherein the high molecular weight polymer solution has a solids content of between 20 and 80 wt.%, preferably between 30 and 70 wt.%, more preferably between 40 and 60 wt.%; the room temperature viscosity is between 100-100000cps, preferably 500-50000cps, more preferably 3000-30000 cps.
10. A method according to claim 8 or 9, characterised in that
The mass ratio of the high-nickel ternary material particles to the high-molecular polymer is 95:5 to 99.9:0.1, preferably 98:2 to 99.8:0.2, and optimally 99:1 to 99.6: 0.4;
the amount of the added lithium manganese iron phosphate is such that the mass ratio of the lithium manganese iron phosphate to the high-nickel ternary material and the high molecular polymer is between 30:70 and 1:99, preferably between 20:80 and 3:97, and more preferably between 15:85 and 5: 95.
CN202011332318.1A 2020-11-24 2020-11-24 Composite material with core-shell structure and preparation method thereof Active CN112436121B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202011332318.1A CN112436121B (en) 2020-11-24 2020-11-24 Composite material with core-shell structure and preparation method thereof

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202011332318.1A CN112436121B (en) 2020-11-24 2020-11-24 Composite material with core-shell structure and preparation method thereof

Publications (2)

Publication Number Publication Date
CN112436121A true CN112436121A (en) 2021-03-02
CN112436121B CN112436121B (en) 2023-01-31

Family

ID=74694031

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202011332318.1A Active CN112436121B (en) 2020-11-24 2020-11-24 Composite material with core-shell structure and preparation method thereof

Country Status (1)

Country Link
CN (1) CN112436121B (en)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112864369A (en) * 2021-03-19 2021-05-28 合肥国轩高科动力能源有限公司 Modified high-nickel ternary cathode material and preparation method thereof
CN114583114A (en) * 2022-03-09 2022-06-03 上海兰钧新能源科技有限公司 Preparation method of positive pole piece, positive pole piece and battery cell
CN115692675A (en) * 2022-11-25 2023-02-03 湖北亿纬动力有限公司 Ternary cathode material with core-shell structure, preparation method thereof and lithium ion battery
CN115863613A (en) * 2023-02-28 2023-03-28 四川轻化工大学 Lithium manganese iron phosphate coated modified high-nickel positive electrode material, and preparation method and application thereof

Citations (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101308925A (en) * 2008-07-04 2008-11-19 深圳市贝特瑞新能源材料股份有限公司 Composite coated positive pole material of lithium ionic cell and preparing method thereof
CN104106161A (en) * 2011-11-30 2014-10-15 科卡姆有限公司 Lithium secondary battery having improved safety and stability
CN105244508A (en) * 2015-11-06 2016-01-13 中国科学院青岛生物能源与过程研究所 Lithium ion battery high-voltage positive electrode material surface coating method
CN105529458A (en) * 2016-03-02 2016-04-27 合肥国轩高科动力能源有限公司 Preparation method of nickel cobalt lithium manganate/lithium manganese iron phosphate composite cathode material of lithium ion battery
CN107546379A (en) * 2017-08-18 2018-01-05 宁波知能新材料有限公司 Iron manganese phosphate for lithium ternary material composite positive pole and preparation method thereof
KR101854076B1 (en) * 2017-04-13 2018-05-03 인천대학교 산학협력단 Positive electrode for lithium secondary battery having post-treated surface by polymer
CN108807863A (en) * 2017-05-05 2018-11-13 宁德时代新能源科技股份有限公司 Modified positive electrode active material, preparation method thereof and electrochemical energy storage device
CN110416525A (en) * 2019-08-08 2019-11-05 上海华谊（集团）公司 The composite material and preparation method of phosphoric acid manganese iron lithium with core-shell structure
CN110444752A (en) * 2019-08-12 2019-11-12 苏州大学 Extended-life lithium ion battery tertiary cathode material and its preparation method and application
CN111689527A (en) * 2020-06-22 2020-09-22 湖南金富力新能源股份有限公司 Preparation method of one-pot double-coated lithium ion battery NCM ternary cathode material
CN111916711A (en) * 2020-08-18 2020-11-10 成都巴莫科技有限责任公司 Ternary cathode material with double-shell structure and preparation method thereof

Patent Citations (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101308925A (en) * 2008-07-04 2008-11-19 深圳市贝特瑞新能源材料股份有限公司 Composite coated positive pole material of lithium ionic cell and preparing method thereof
CN104106161A (en) * 2011-11-30 2014-10-15 科卡姆有限公司 Lithium secondary battery having improved safety and stability
CN105244508A (en) * 2015-11-06 2016-01-13 中国科学院青岛生物能源与过程研究所 Lithium ion battery high-voltage positive electrode material surface coating method
CN105529458A (en) * 2016-03-02 2016-04-27 合肥国轩高科动力能源有限公司 Preparation method of nickel cobalt lithium manganate/lithium manganese iron phosphate composite cathode material of lithium ion battery
KR101854076B1 (en) * 2017-04-13 2018-05-03 인천대학교 산학협력단 Positive electrode for lithium secondary battery having post-treated surface by polymer
CN108807863A (en) * 2017-05-05 2018-11-13 宁德时代新能源科技股份有限公司 Modified positive electrode active material, preparation method thereof and electrochemical energy storage device
CN107546379A (en) * 2017-08-18 2018-01-05 宁波知能新材料有限公司 Iron manganese phosphate for lithium ternary material composite positive pole and preparation method thereof
CN110416525A (en) * 2019-08-08 2019-11-05 上海华谊（集团）公司 The composite material and preparation method of phosphoric acid manganese iron lithium with core-shell structure
CN110444752A (en) * 2019-08-12 2019-11-12 苏州大学 Extended-life lithium ion battery tertiary cathode material and its preparation method and application
CN111689527A (en) * 2020-06-22 2020-09-22 湖南金富力新能源股份有限公司 Preparation method of one-pot double-coated lithium ion battery NCM ternary cathode material
CN111916711A (en) * 2020-08-18 2020-11-10 成都巴莫科技有限责任公司 Ternary cathode material with double-shell structure and preparation method thereof

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
ZHEN CHEN,ET AL,.: ""Recent progress in surface coating of layered LiNixCoyMnzO2 for lithium-ion batteries"", 《MATERIALS RESEARCH BULLETIN》 *
肖利等: "锂离子电池三元正极材料包覆工艺研究进展", 《功能材料》 *
贺志龙等: ""磷酸锰铁锂复合三元体系及对复合方式的研究"", 《电源技术》 *

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112864369A (en) * 2021-03-19 2021-05-28 合肥国轩高科动力能源有限公司 Modified high-nickel ternary cathode material and preparation method thereof
CN112864369B (en) * 2021-03-19 2022-02-18 合肥国轩高科动力能源有限公司 Modified high-nickel ternary cathode material and preparation method thereof
CN114583114A (en) * 2022-03-09 2022-06-03 上海兰钧新能源科技有限公司 Preparation method of positive pole piece, positive pole piece and battery cell
CN115692675A (en) * 2022-11-25 2023-02-03 湖北亿纬动力有限公司 Ternary cathode material with core-shell structure, preparation method thereof and lithium ion battery
CN115863613A (en) * 2023-02-28 2023-03-28 四川轻化工大学 Lithium manganese iron phosphate coated modified high-nickel positive electrode material, and preparation method and application thereof

Also Published As

Publication number Publication date
CN112436121B (en) 2023-01-31

Similar Documents

Publication Publication Date Title
CN110048153B (en) Solid metal lithium battery and preparation method thereof
CN112436121B (en) Composite material with core-shell structure and preparation method thereof
EP3288105B1 (en) Binder for nonaqueous electrolyte secondary battery electrodes and use of same
CN101457131B (en) Water binding agent for lithium ionic cell electric pole material and preparation method thereof
KR20190039993A (en) Acrylonitrile Copolymer Adhesives and Their Applications in Lithium Ion Batteries
JP6665857B2 (en) Composition for non-aqueous electrolyte secondary battery electrode mixture layer, method for producing the same, and use thereof
KR20170129125A (en) Compositions for non-aqueous secondary battery functional layer, functional layer for non-aqueous secondary battery, and non-aqueous secondary battery
KR101111076B1 (en) Binder Composition for Secondary Battery, and Electrode Employed with the Same, and Lithium Secondary Battery
CN108475786B (en) Aqueous binder composition for secondary battery electrode, slurry for secondary battery electrode, binder, secondary battery electrode, and secondary battery
KR20200009051A (en) Materials for electrochemical cells and methods for their preparation and use
CN108780892B (en) Binder composition for nonaqueous secondary battery electrode, slurry composition for nonaqueous secondary battery electrode, electrode for nonaqueous secondary battery, and nonaqueous secondary battery
US10541423B2 (en) Electrode mixture layer composition for nonaqueous electrolyte secondary battery, manufacturing method thereof and use therefor
WO2006038652A1 (en) Electrode composition, electrode and battery
CN112701277A (en) Lithium ion battery prelithiation additive and application thereof
WO2021253673A1 (en) Binder composition for secondary battery
CN110993947A (en) Modified anode material and lithium ion battery
CN112133916A (en) Silicon-based negative electrode material binder of lithium ion battery and preparation method and application thereof
CN111684632B (en) Binder composition for secondary battery electrode and electrode mixture
CN113372482A (en) Acrylic acid multipolymer, preparation method thereof and application thereof in positive pole piece
JPH11288720A (en) Secondary battery binder composition, battery electrode slurry, battery electrode and secondary battery
WO2021253616A1 (en) Binder composition for secondary battery
CN113346131A (en) Composite polymer gel solid electrolyte, preparation method thereof and application of lithium metal battery
JP2023529531A (en) Binder composition for secondary battery
CN113725438B (en) Water-based composite binder for solid lithium battery and application thereof
KR102563589B1 (en) Anode slurry composition for secondary battery

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant