CN109879333B - Method for preparing lithium battery anode material with core-shell structure by secondary molten salt method - Google Patents
Method for preparing lithium battery anode material with core-shell structure by secondary molten salt method Download PDFInfo
- Publication number
- CN109879333B CN109879333B CN201910301582.XA CN201910301582A CN109879333B CN 109879333 B CN109879333 B CN 109879333B CN 201910301582 A CN201910301582 A CN 201910301582A CN 109879333 B CN109879333 B CN 109879333B
- Authority
- CN
- China
- Prior art keywords
- nickel
- molten salt
- nickel ternary
- salt
- core
- 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.)
- Active
Links
Images
Classifications
-
- 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
- Battery Electrode And Active Subsutance (AREA)
Abstract
The invention discloses a high-nickel ternary monocrystal, the chemical formula of which is LiNixCoyMnzO2The invention also discloses a lithium battery anode material with the core-shell structure and a preparation method thereof. According to the material disclosed by the invention, the core part is improved in nickel content (high-nickel ternary material) to improve the battery capacity, and the shell part (low-nickel ternary material) is improved in manganese content to improve the structural stability of the material. The core and the shell have similar lattice structures, and the phenomenon of lattice mismatch of the interface of the core and the shell can be relieved. The surface coating layer can improve the interface stability of the high-nickel ternary single crystal, reduce the corrosion of electrolyte, finally effectively reduce the surface parasitic reaction of the high-nickel ternary single crystal and improve the long-life cycle performance of the material.
Description
Technical Field
The invention belongs to the technical field of lithium battery preparation, and particularly relates to a method for preparing a core-shell structure lithium battery cathode material by a secondary molten salt method.
Background
At present, LiCoO has been successfully commercialized2、LiFePO4、LiMn2O4The lithium battery anode material can not meet the market demand. Layered transition metal oxides with higher specific capacities are of interest, with high nickel ternary materials (not strictly defined, LiNi)xCoyMnzO2X + y + z is 1, usually x is more than or equal to 0.5), the specific capacity can reach 200mAh/g, the energy density of the single battery can reach 300Wh/kg, and the lithium ion battery can better meet the urgent requirement of the high-energy density lithium ion battery for the current vehicle compared with other anode material systems. However, high nickel ternary materials face severe capacity and voltage droop problems, which are key challenges limiting their commercialization. Many researches find that the surface stability of the high-nickel ternary material is poor, (1) the material is very easy to react with CO in air2And H2Side reaction of O and serious parasitic reaction of O and electrolyte. Therefore, the design is improved from the source of the material, a core-shell structure of a heterogeneous coating layer is constructed on the surface of the high-nickel ternary single crystal, the nickel content (high-nickel ternary material) is improved in the core part to improve the battery capacity, and the manganese content is improved in the shell part (low-nickel ternary material) to improve the structural stability of the material. Thereby blocking high nickel trisThe surface of the element material is in direct contact with the environment (electrolyte), so that the surface stability of the material is improved, and the long-life cycle performance of the battery is effectively improved. Compared with other inert surface coating materials (referring to materials which can not store lithium), the low-nickel ternary material serving as a heterogeneous coating layer can improve the surface stability of the high-nickel ternary material and can also be used as a positive electrode material to participate in charge-discharge electrochemical reactions.
The molten salt method adopts low-melting-point salt as a reaction medium, liquid phase appears in the synthesis process, reactants of nickel, cobalt and manganese have certain solubility in the liquid phase, the diffusion rate of ions is greatly accelerated, the metal ions of nickel, cobalt and manganese are mixed in the liquid phase in an atomic scale manner, and the reaction is converted from solid-solid reaction to solid-liquid reaction. The controllable nucleation, crystal growth and other processes are realized by regulating and controlling the mass ratio of the reactants to the molten salt and the reaction temperature gradient. In recent years, molten salt synthesis has been widely studied in the field of inorganic nonmetallic material synthesis, and the application range is also more and more extensive. Particularly has obvious advantages in the field of preparation of the uniform micron-sized single crystals.
Disclosure of Invention
The purpose of the invention is as follows: aiming at the problems in the prior art, the invention aims to provide the high-nickel ternary single crystal.
The invention also aims to solve the technical problem of providing a lithium battery anode material with a core-shell structure.
The invention also aims to solve the technical problem of providing a preparation method of the high-nickel ternary single crystal.
The invention finally solves the technical problem of providing a method for preparing the lithium battery anode material with the core-shell structure by a secondary molten salt method.
The invention has the advantages of low cost of raw materials for preparation, simple equipment, recyclable molten salt and no emission of solid, liquid and gas wastes. According to the monocrystal/heterogeneous layer core-shell structure disclosed by the invention, the nickel content (high-nickel ternary material) is increased in the core part to improve the battery capacity, and the manganese content is increased in the shell part (low-nickel ternary material) to improve the structural stability of the material. The core and the shell have similar lattice structures, and the phenomenon of lattice mismatch of the interface of the core and the shell can be relieved. Compared with other inert surface coating materials (referring to materials which can not store lithium), the low-nickel ternary material serving as a heterogeneous coating layer can improve the surface stability of the high-nickel ternary material and can also be used as a positive electrode material to participate in charge-discharge electrochemical reactions.
The technical scheme is as follows: in order to solve the technical problems, the invention adopts the following technical scheme: the invention provides a high-nickel ternary single crystal, which has a chemical formula of LiNixCoyMnzO2Wherein x + y + z is 1, and 1 > x is not less than 0.7.
The invention also comprises a core-shell structure lithium battery anode material, wherein the core of the core-shell structure lithium battery anode material is the high-nickel ternary single crystal, and the shell is a low-nickel ternary material nano coating layer.
Wherein the chemical formula of the low-nickel ternary material nano coating layer is LiNixCoyMnzO2Wherein x + y + z is 1, x is more than 0 and less than or equal to 0.4, and z is more than 1 and more than or equal to 0.3), and the coating layer accounts for 1-5% of the total mass ratio of the material (the core-shell structure lithium battery positive electrode material).
The invention also discloses a method for preparing the lithium battery anode material with the core-shell structure by a secondary molten salt method, which comprises the following steps:
1) preparing molten salt: separately weighing NaCl, KCl and Na2SO4Fully grinding and uniformly mixing to obtain molten salt for later use;
2) preparing raw materials: grinding and uniformly mixing raw materials lithium salt, nickel salt, cobalt salt and manganese salt required for preparing the high-nickel ternary material to obtain a reactant 1, and grinding and uniformly mixing raw materials lithium salt, nickel salt, cobalt salt and manganese salt required for preparing the low-nickel ternary material to obtain a reactant 2; wherein, in the two raw materials (reactant 1 and reactant 2), the lithium salt is 5% more than the amount required by the stoichiometric ratio;
3) synthesizing a high-nickel ternary micron monocrystal at high temperature by a molten salt growth method: fully mixing the molten salt in the step 1) with the reactant 1 in the step 2), grinding, reacting at a high temperature, cooling after the reaction is finished, and cooling along with a furnace to obtain a mixture 1;
4) dissolving the mixture 1 in a solvent to form a suspension, adding the reactant 2, stirring for dissolving, concentrating, drying, grinding and uniformly mixing to obtain a mixture 2;
5) carrying out molten salt reaction on the mixture 2 obtained in the step 4) again to synthesize a product of the low-nickel ternary material nano-layer coated high-nickel ternary micron monocrystal;
6) and (5) washing, separating and collecting the product obtained in the step 5) to obtain the surface-modified high-nickel ternary single crystal material.
Wherein, NaCl, KCl and Na in the step 1)2SO4The mass ratio of (A) to (B) is 30-60%: 20-35%: 20 to 40 percent.
Wherein, the lithium salt in the step 2) is one or two of lithium hydroxide, lithium acetate, lithium carbonate and lithium nitrate; the nickel salt is one or two of nickel oxide, nickel acetate, nickel carbonate, nickel chloride and nickel sulfate; the manganese salt is one or two of manganese dioxide, manganese acetate, manganese carbonate, manganese chloride and manganese sulfate; the cobalt salt is one or two of cobaltosic oxide, cobalt acetate, cobalt carbonate, cobalt nitrate, cobalt chloride and cobalt sulfate.
Wherein, the high-temperature synthesis step of the step 3) is divided into two stages, the first stage reaction temperature is 600-.
Wherein the cooling rate of the step 3) is 20-60 ℃/h, and the furnace is cooled after the temperature is reduced to 500 ℃.
Wherein the stirring speed in the step 4) is 200-500rpm, the solid is concentrated in water bath at 80 ℃ after dissolution, and the obtained solid is dried by air blowing, ground and uniformly mixed for later use.
Wherein, the solvent in the step 4) is one or two of deionized water, ethanol and isopropanol.
Wherein, the temperature of the molten salt reaction in the step 5) is 600-800 ℃, the synthesis time is 2-6h, and the furnace is cooled after the reaction is finished.
Wherein, the high nickel ternary material obtained in the step 3) is micron single crystal, and the particle size (D50) is between 1.5 and 6 microns.
And (3) assembling the lithium ion battery by taking the surface-modified high-nickel ternary monocrystal material obtained in the step 6) as a positive electrode material, and testing the electrochemical performance.
Wherein, the two molten salt reactions are processed at high temperature in air atmosphere, the atmosphere in the cavity is normal pressure air, and the gas flow rate of the cavity is 100-.
Wherein the mass ratio of the molten salt to the target anode material is 1.1-5.0: 1.
Has the advantages that: the invention adopts a molten salt growth method to synthesize a micron single crystal type high nickel ternary material (LiNi)xCoyMnzO2X + y + z is 1, and 1 > x is not less than 0.7), and then a single crystal/heterogeneous layer core-shell structure material is obtained by a molten salt growth method again, wherein the coating layer is LiNixCoyMnzO2(x + y + z is 1, x is more than 0 and less than or equal to 0.4, and z is more than 1 and more than or equal to 0.3), and the coating layer accounts for 1-5% of the total mass ratio of the material. According to the material disclosed by the invention, the core part is improved in nickel content (high-nickel ternary material) to improve the battery capacity, and the shell part (low-nickel ternary material) is improved in manganese content to improve the structural stability of the material. The core and the shell have similar lattice structures, and the phenomenon of lattice mismatch of the interface of the core and the shell can be relieved. The surface coating layer can improve the interface stability of the high-nickel ternary single crystal, reduce the corrosion of electrolyte, finally effectively reduce the surface parasitic reaction of the high-nickel ternary single crystal and improve the long-life cycle performance of the material.
Drawings
FIG. 1X-ray diffraction pattern of the sample of example 5;
FIG. 2 scanning electron micrographs of a sample of example 6;
FIG. 3 TEM image of a sample of example 7;
FIG. 4 SEM image of the sample obtained in example 8.
Detailed Description
The following are preferred embodiments of the present invention, which are intended to be illustrative only and not limiting, and all changes that come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.
Example 1 high-nickel ternary single crystal LiNi0.7Co0.15Mn0.15O2Preparation of
1) Preparing NaCl-KCl-Na according to the mass ratio of 30 percent to 40 percent2SO4And (4) melting salt, fully grinding in a dry environment, and uniformly mixing for later use. High nickel ternary material LiNi0.7Co0.15Mn0.15O2Weighing lithium hydroxide, nickel carbonate, cobalt carbonate and manganese carbonate according to the stoichiometric ratio, grinding and uniformly mixing the raw materials to obtain a reactant 1. Wherein the lithium hydroxide is 5% in mass excess of the amount required by its stoichiometric ratio. The mass ratio of the molten salt to the target cathode material (the cathode material of the lithium battery with the core-shell structure) is 5: 1.
2) Fully mixing the molten salt with a reactant 1, grinding, and reacting at a high temperature: the reaction was continued at 600 ℃ for 3h and subsequently at 900 ℃ for 10 h. After the reaction is finished, the cooling rate is 60 ℃/h, and the reaction product is obtained after the temperature is reduced to 500 ℃ and then is cooled along with the furnace, wherein the reaction product is a mixture.
3) Separating the reaction product, washing with a solvent, and drying to obtain the micron monocrystal/nickel-rich ternary material with particle size (D50) of 6 microns.
Example 2 high nickel ternary material LiNi0.8Co0.1Mn0.1O2Preparation of
1) Preparing NaCl-KCl-Na according to the mass ratio of 60 percent to 20 percent2SO4And (4) melting salt, fully grinding in a dry environment, and uniformly mixing for later use. High nickel ternary material LiNi0.8Co0.1Mn0.1O2The required raw materials of lithium hydroxide, nickel carbonate, cobalt carbonate and manganese carbonate are weighed according to the stoichiometric ratio, ground and uniformly mixed for later use. The lithium hydroxide was 5% in mass excess of the amount required for its stoichiometric ratio. The mass ratio of the molten salt to the target anode material is 1.1: 1
2) Fully mixing the molten salt and the reactants, grinding and reacting at high temperature. The reaction was continued at 600 ℃ for 3h and subsequently at 700 ℃ for 10 h. After the reaction is finished, the cooling rate is 20 ℃/h, the reaction product is obtained by cooling along with the furnace after the temperature is reduced to 500 ℃, and the reaction product is a mixture.
3) Separating the reaction product, washing with a solvent, and drying to obtain the micron monocrystal/nickel-rich ternary material with particle size (D50) of 1.8 microns.
Example 3 high nickel ternary material LiNi0.8Co0.1Mn0.1O2Preparation of
1) Preparing NaCl-KCl-Na according to the mass ratio of 40 percent to 20 percent to 40 percent2SO4And (4) melting salt, fully grinding in a dry environment, and uniformly mixing for later use. High nickel ternary material LiNi0.8Co0.1Mn0.1O2The required raw materials of lithium hydroxide, nickel carbonate, cobalt carbonate and manganese carbonate are weighed according to the stoichiometric ratio, ground and uniformly mixed for later use. The lithium hydroxide was 5% in mass excess of the amount required for its stoichiometric ratio. The mass ratio of the molten salt to the target cathode material is 2.0: 1.
2) Fully mixing the molten salt and the reactants, grinding and reacting at high temperature. The reaction was continued at 800 ℃ for 3h and subsequently at 750 ℃ for 10 h. And after the reaction is finished, the cooling rate is 50 ℃/h, and the reaction product is obtained by cooling along with the furnace after the temperature is reduced to 500 ℃, wherein the reaction product is a mixture.
3) Separating the reaction product, washing with a solvent, and drying to obtain the micron monocrystal/high-nickel ternary material with a particle size (D50) of 3.5 microns.
Example 4 high nickel ternary material LiNi0.8Co0.1Mn0.1O2Preparation of
1) Preparing NaCl-KCl-Na according to the mass ratio of 40 percent to 20 percent to 40 percent2SO4And (4) melting salt, fully grinding in a dry environment, and uniformly mixing for later use. High nickel ternary material LiNi0.8Co0.1Mn0.1O2The required raw materials of lithium hydroxide, nickel carbonate, cobalt carbonate and manganese carbonate are weighed according to the stoichiometric ratio, ground and uniformly mixed for later use. The lithium hydroxide was 5% in mass excess of the amount required for its stoichiometric ratio. The mass ratio of the molten salt to the target cathode material is 3.0: 1.
2) Fully mixing the molten salt and the reactants, grinding and reacting at high temperature. The reaction was continued at 900 ℃ for 3h and subsequently at 750 ℃ for 10 h. After the reaction is finished, the cooling rate is 40 ℃/h, and after the temperature is reduced to 500 ℃, the reaction product is obtained by cooling along with the furnace, and the reaction product is a mixture.
3) Separating the reaction product, washing with a solvent, and drying to obtain the micron monocrystal/high-nickel ternary material with particle size (D50) of 4 microns.
Example 5 preparation of surface-modified high-nickel ternary single crystal material-core-shell structure lithium battery cathode material
The mixture obtained in step 2) of example 1 was dissolved in deionized water to completely dissolve the molten salt, and the mixture was thoroughly stirred to obtain a suspension. The low-nickel ternary material LiNi1/3Co1/3Mn1/3O2The reaction raw materials are added into the suspension by weighing lithium hydroxide, nickel acetate, cobalt acetate and manganese acetate according to the stoichiometric ratio, and fully stirred to completely dissolve the soluble salt. The suspension was concentrated under stirring at 600rpm in a water bath at 80 ℃. Drying the obtained solid by blowing, grinding and mixing uniformly for later use. And weighing the reaction raw materials of the coating layer according to the proportion that the coating layer accounts for 1 percent of the total mass of the core-shell structure cathode material.
And carrying out molten salt reaction again, and reacting for 2h at 800 ℃ to generate a low-nickel ternary material nano layer coated on the surface of the high-nickel ternary micron monocrystal. And cooling along with the furnace after the reaction is finished. And washing the obtained product with water to remove molten salt, separating, drying and collecting for later use. The molten salt can be recycled. FIG. 1 is an X-ray diffraction diagram of the sample, wherein characteristic spectrum peaks and high-nickel ternary material LiNi are shown in the diagram0.7Co0.15Mn0.15O2The standard spectrogram has consistent peak positions, no impurity peak and sharp diffraction peak, which indicates that the material has high crystallinity.
Example 6 preparation of surface-modified high-nickel ternary single crystal material-core-shell structure lithium battery cathode material
The mixture obtained in step 2 of example 2 was dissolved in deionized water to dissolve the molten salt completely, and the mixture was stirred thoroughly to obtain a suspension.
The low-nickel ternary material LiNi1/3Co1/3Mn1/3O2The reaction raw materials of lithium hydroxide, nickel acetate, cobalt acetate and manganese acetate are weighed according to the stoichiometric ratio, added into the suspension, and fully stirred to completely dissolve the soluble salt. The suspension was concentrated under stirring at 600rpm in a water bath at 80 ℃. Drying the obtained solid by blowing, grinding and mixing uniformly for later use. Weighing the reaction raw materials of the coating layer according to the proportion that the coating layer accounts for 5 percent of the total mass of the materials.
And carrying out molten salt reaction again, and reacting for 6h at 600 ℃ to generate a low-nickel ternary material nano layer coated on the surface of the high-nickel ternary micron monocrystal. And cooling along with the furnace after the reaction is finished. Washing the obtained product with water to remove the molten salt, separating, drying and collecting for later use, wherein the molten salt can be recycled. The obtained material is consistent with the peak position of the corresponding standard spectrogram and has no impurity peak.
Example 7 preparation of surface-modified high-nickel ternary single crystal material-core-shell structure lithium battery cathode material
The mixture obtained in step 2 of example 3 was dissolved in deionized water to completely dissolve the molten salt, and the mixture was stirred sufficiently to obtain a suspension.
The low-nickel ternary material LiNi0.4Co0.2Mn0.4O2The reaction raw materials of lithium hydroxide, nickel acetate, cobalt acetate and manganese acetate are weighed according to the stoichiometric ratio, added into the suspension, and fully stirred to completely dissolve the soluble salt. The suspension was concentrated under stirring at 600rpm in a water bath at 80 ℃. Drying the obtained solid by blowing, grinding and mixing uniformly for later use. Weighing the reaction raw materials of the coating layer according to the mass ratio of the coating layer to the total material of 2.0%.
And carrying out molten salt reaction again, and reacting for 5 hours at 750 ℃ to generate a low-nickel ternary material nano layer coated on the surface of the high-nickel ternary micron monocrystal. And cooling along with the furnace after the reaction is finished. And washing the obtained product with water to remove molten salt, separating, drying and collecting for later use. The molten salt can be recycled. The obtained material is consistent with the peak position of the corresponding standard spectrogram and has no impurity peak.
Example 8 preparation of surface-modified high-nickel ternary single crystal material-core-shell structure lithium battery cathode material
The mixture obtained in step 2 of example 4 was dissolved in deionized water/ethanol (volume ratio 0.7: 0.3) to completely dissolve the molten salt, and the mixture was thoroughly stirred to obtain a suspension.
The low-nickel ternary material LiNi1/3Co1/3Mn1/3O2The reaction raw materials of lithium hydroxide, nickel acetate, cobalt acetate and manganese acetate are weighed according to the stoichiometric ratio, added into the suspension, and fully stirred to completely dissolve the soluble salt. The suspension was stirred at 300rpm in a 75 ℃ water bathAnd (5) concentrating. Drying the obtained solid by blowing, grinding and mixing uniformly for later use. Weighing the reaction raw materials of the coating layer according to the mass ratio of the coating layer to the total material of 2.0%.
And carrying out molten salt reaction again, and reacting for 4h at 700 ℃ to generate a low-nickel ternary material nano layer coated on the surface of the high-nickel ternary micron monocrystal. And cooling along with the furnace after the reaction is finished. And washing the obtained product with water to remove molten salt, separating, drying and collecting for later use. The molten salt can be recycled. The obtained material is consistent with the peak position of the corresponding standard spectrogram and has no impurity peak.
Comparative example
The micron single crystal type high nickel ternary material which is not subjected to surface modification in the embodiment 1 is used as a positive electrode material, a lithium ion battery is assembled, and the electrochemical performance is tested.
Experimental example:
the surface-modified high-nickel ternary single crystal material obtained in examples 5-8 and the surface-unmodified micron single crystal type high-nickel ternary material of the comparative example were used as positive electrode materials to assemble lithium ion batteries, and electrochemical performance was tested. See table 1 for results.
TABLE 1 electrochemical properties of examples 5 to 8 and comparative samples (laminate pouch cell, negative electrode: graphite, voltage interval: 3-4.3V, current density 18mA/g)
*The X-ray photoelectron spectroscopy (XPS) measurement method is adopted, and the data is the peak area ratio of metal ions to graphite. It can be found that the comparative sample is not surface-modified, and after many charge-discharge cycles, trace metal ions in the sample are dissolved out and pass through the electrolyte to deposit on the surface of the negative graphite. And after the sample subjected to surface modification is circulated, the content of the detected metal ions on the surface of the corresponding negative electrode graphite is only 10% of that of the comparative example. Obviously, the surface of the high-nickel ternary single crystal is repairedThe decoration layer can effectively improve the stability of the main material, thereby improving the cycle performance and the capacity of the battery.
Claims (8)
1. The high-nickel ternary single crystal is characterized in that the chemical formula of the high-nickel ternary single crystal is LiNixCoyMnzO2Wherein x + y + z =1, 1 > x is not less than 0.7, the high-nickel ternary single crystal is a micron single crystal, the particle size D50 is 1.8-6 microns, and the preparation method of the high-nickel ternary single crystal is as follows:
1) according to the mass ratio of 30-60%: 20-35%: 20-40% of prepared NaCl-KCl-Na2SO4Molten salt, fully grinding and uniformly mixing in a dry environment for later use, and preparing the high-nickel ternary material LiNixCoyMnzO2Weighing lithium hydroxide, nickel carbonate, cobalt carbonate and manganese carbonate according to a stoichiometric ratio, grinding and uniformly mixing the raw materials to obtain a reactant 1, wherein the mass ratio of the lithium hydroxide to the stoichiometric ratio is 5% in excess, and the mass ratio of the molten salt to a target cathode material is 1.1: 1-5: 1; the target anode material is a core-shell structure lithium battery anode material, the core of the core-shell structure lithium battery anode material is a high-nickel ternary monocrystal, and the shell is a low-nickel ternary material nano coating layer; the chemical formula of the low-nickel ternary material nano coating layer is LiNixCoyMnzO2Wherein x + y + z =1, 0<x ≤0.4、1＞z≥0.3；
2) Fully mixing the molten salt with a reactant 1, grinding, and reacting at a high temperature: reacting for 3 hours at 600-900 ℃, then continuing to react for 10 hours at 700-900 ℃, after the reaction is finished, cooling at a rate of 40-60 ℃/h to 500 ℃, and then cooling with a furnace to obtain a reaction product, wherein the reaction product is a mixture;
3) and separating, washing and drying the reaction product by using a solvent, wherein the obtained high-nickel ternary material is a micron monocrystal, and the particle size D50 is 1.8-6 microns.
2. The method for preparing the positive electrode material of the lithium battery with the core-shell structure, which is disclosed by claim 1, by a secondary molten salt method is characterized by comprising the following steps of:
1) preparing molten salt: separately weighing NaCl, KCl and Na2SO4Fully grinding and uniformly mixing to obtain molten salt for later use;
2) preparing raw materials: grinding and uniformly mixing raw materials lithium salt, nickel salt, cobalt salt and manganese salt required for preparing the high-nickel ternary single crystal material to obtain a reactant 1, and grinding and uniformly mixing raw materials lithium salt, nickel salt, cobalt salt and manganese salt required for preparing the low-nickel ternary single crystal material to obtain a reactant 2;
3) synthesizing a high-nickel ternary micron monocrystal at high temperature by a molten salt growth method: fully mixing the molten salt prepared in the step 1) with the reactant 1 in the step 2), grinding, reacting at a high temperature, cooling after the reaction is finished, and cooling along with a furnace to obtain a mixture 1;
4) dissolving the mixture 1 in water to form a suspension, adding the reactant 2, stirring to dissolve, concentrating, drying, grinding and uniformly mixing to obtain a mixture 2;
5) carrying out molten salt reaction on the mixture 2 obtained in the step 4) again to synthesize a product of the low-nickel ternary material nano-layer coated high-nickel ternary micron monocrystal;
6) and (5) washing, separating and collecting the product obtained in the step 5) to obtain the surface-modified high-nickel ternary single crystal material.
3. The method for preparing the lithium battery cathode material with the core-shell structure by the secondary molten salt growth method according to claim 2, wherein NaCl, KCl and Na in the step 1)2SO4The mass ratio of (A) to (B) is 30-60%: 20-35%: 20 to 40 percent.
4. The method for preparing the lithium battery cathode material with the core-shell structure by the secondary molten salt method according to claim 3, wherein the lithium salt in the step 2) is one or two of lithium hydroxide, lithium acetate, lithium carbonate and lithium nitrate; the nickel salt is one or two of nickel oxide, nickel acetate, nickel carbonate, nickel chloride and nickel sulfate; the manganese salt is one or two of manganese dioxide, manganese acetate, manganese carbonate, manganese chloride and manganese sulfate; the cobalt salt is one or two of cobaltosic oxide, cobalt acetate, cobalt carbonate, cobalt nitrate, cobalt chloride and cobalt sulfate.
5. The method for preparing the lithium battery cathode material with the core-shell structure by the secondary molten salt method as claimed in claim 2, wherein the high-temperature synthesis step in the step 3) is divided into two stages, wherein the reaction temperature in the first stage is 600-900 ℃, and the synthesis time is 2-6h, and then the reaction temperature in the second stage is 700-900 ℃, and the synthesis time is 5-12 h.
6. The method for preparing the lithium battery cathode material with the core-shell structure by the secondary molten salt growth method according to claim 2, wherein the cooling rate in the step 3) is 20-60 ℃/h, and the lithium battery cathode material is cooled along with a furnace after being cooled to 500 ℃.
7. The method for preparing the lithium battery cathode material with the core-shell structure by the secondary molten salt method as claimed in claim 2, wherein the stirring speed in the step 4) is 200-500 rpm.
8. The method for preparing the lithium battery cathode material with the core-shell structure by the secondary molten salt method as claimed in claim 2, wherein the temperature of the secondary molten salt reaction in the step 5) is 600-800 ℃, and the synthesis time is 2-6 h.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910301582.XA CN109879333B (en) | 2019-04-15 | 2019-04-15 | Method for preparing lithium battery anode material with core-shell structure by secondary molten salt method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910301582.XA CN109879333B (en) | 2019-04-15 | 2019-04-15 | Method for preparing lithium battery anode material with core-shell structure by secondary molten salt method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN109879333A CN109879333A (en) | 2019-06-14 |
| CN109879333B true CN109879333B (en) | 2021-07-27 |
Family
ID=66937357
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910301582.XA Active CN109879333B (en) | 2019-04-15 | 2019-04-15 | Method for preparing lithium battery anode material with core-shell structure by secondary molten salt method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN109879333B (en) |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114188526B (en) * | 2020-09-15 | 2024-06-28 | 中国石油化工股份有限公司 | Single crystal positive electrode material, preparation method thereof and application of single crystal positive electrode material in lithium ion battery |
| CN112357972A (en) * | 2020-09-30 | 2021-02-12 | 宜宾光原锂电材料有限公司 | Low-nickel cobalt-free precursor, cathode material and preparation method thereof |
| CN113013395A (en) * | 2021-03-26 | 2021-06-22 | 蜂巢能源科技有限公司 | Positive electrode material and preparation method and application thereof |
| CN113381005B (en) * | 2021-05-27 | 2022-10-11 | 厦门大学 | Single-crystal ternary cathode material, continuous preparation method and device and application |
| CN115084506B (en) * | 2022-05-18 | 2024-07-09 | 广东邦普循环科技有限公司 | Large-particle-size monocrystal ternary positive electrode material, and preparation method and application thereof |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102324504A (en) * | 2011-10-24 | 2012-01-18 | 中南大学 | Lithium ion battery anode material with LiCoO2 coated on surface and preparation method for lithium ion battery anode material |
| CN104409716A (en) * | 2014-10-30 | 2015-03-11 | 中国科学院过程工程研究所 | Nickel lithium ion battery positive material with concentration gradient, and preparation method thereof |
| CN106848296A (en) * | 2017-03-20 | 2017-06-13 | 华南师范大学 | A kind of lithium ion battery manganese base lithium-rich anode material and preparation method thereof |
| CN108172799A (en) * | 2017-12-28 | 2018-06-15 | 清远佳致新材料研究院有限公司 | A kind of tertiary cathode material of nucleocapsid structure lithium ion battery and preparation method thereof |
-
2019
- 2019-04-15 CN CN201910301582.XA patent/CN109879333B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102324504A (en) * | 2011-10-24 | 2012-01-18 | 中南大学 | Lithium ion battery anode material with LiCoO2 coated on surface and preparation method for lithium ion battery anode material |
| CN104409716A (en) * | 2014-10-30 | 2015-03-11 | 中国科学院过程工程研究所 | Nickel lithium ion battery positive material with concentration gradient, and preparation method thereof |
| CN106848296A (en) * | 2017-03-20 | 2017-06-13 | 华南师范大学 | A kind of lithium ion battery manganese base lithium-rich anode material and preparation method thereof |
| CN108172799A (en) * | 2017-12-28 | 2018-06-15 | 清远佳致新材料研究院有限公司 | A kind of tertiary cathode material of nucleocapsid structure lithium ion battery and preparation method thereof |
Also Published As
| Publication number | Publication date |
|---|---|
| CN109879333A (en) | 2019-06-14 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN109879333B (en) | Method for preparing lithium battery anode material with core-shell structure by secondary molten salt method | |
| CN113036095B (en) | Preparation method of single-crystal-morphology lithium ion battery positive electrode material | |
| KR101757490B1 (en) | Nickel-cobalt-manganese compound particle powder and method for producing same, lithium composite oxide particle powder and method for producing same, and nonaqueous electrolyte secondary battery | |
| CN104810517B (en) | Nonaqueous electrolyte secondary battery, Li-Ni composite oxide particle powder, and method for producing same | |
| KR101587293B1 (en) | Li-Ni-BASED COMPOSITE OXIDE PARTICLE POWDER FOR RECHARGEABLE BATTERY WITH NONAQUEOUS ELECTROLYTE, PROCESS FOR PRODUCING THE POWDER, AND RECHARGEABLE BATTERY WITH NONAQUEOUS ELECTROLYTE | |
| JP4546937B2 (en) | Cathode active material for non-aqueous electrolyte lithium secondary battery, method for producing the same, and lithium secondary battery including the same | |
| KR101313575B1 (en) | Manufacturing method of positive active material precursor and lithium metal composite oxides for lithium secondary battery | |
| CN108767216B (en) | Lithium ion battery anode material with variable slope and full concentration gradient and synthesis method thereof | |
| CN106910887B (en) | Lithium-rich manganese-based positive electrode material, preparation method thereof and lithium ion battery containing positive electrode material | |
| WO2015039490A1 (en) | Lithium-rich anode material and preparation method thereof | |
| NZ538480A (en) | Lithium-nickel-cobalt-manganese containing composite oxide, material for positive electrode active material for lithium secondary battery, and methods for producing these | |
| WO2009119104A1 (en) | Oxycobalt hydroxide particulate powder and manufacturing method therefor, as well as lithium cobaltate particulate powder, manufacturing method therefor, and non-aqueous electrolyte secondary battery using the same | |
| TWI622212B (en) | Cathode compositions for lithium-ion batteries | |
| WO2010139142A1 (en) | Positive electrode materials of secondary lithium battery and preparation methods thereof | |
| CN112830524A (en) | Transition metal oxide positive electrode material of single crystal lithium and preparation method and application thereof | |
| CN113497227A (en) | Full-concentration-gradient-adjustable mono-like lithium-rich layered oxide cathode material and preparation method thereof | |
| JP3461800B2 (en) | Lithium manganese nickel composite oxide and method for producing the same | |
| CN112744872A (en) | Liquid-phase phosphorus element doping modification preparation method of high-nickel anode material | |
| JPH111324A (en) | Platy nickel hydroxide particle, its production and production of lithium-nickel complex oxide particle using the nickel hydroxide particle as raw material | |
| CN117712369A (en) | High-capacity ternary positive electrode material and preparation method thereof | |
| CN114804235A (en) | High-voltage nickel cobalt lithium manganate positive electrode material and preparation method and application thereof | |
| CN111362318A (en) | Nickel-cobalt-manganese carbonate and preparation method and application thereof | |
| JP7273260B2 (en) | Positive electrode active material for lithium ion secondary battery, method for producing the same, and lithium ion secondary battery | |
| CN112582587A (en) | Core-shell structure high-nickel cathode material with single crystal as core and preparation method thereof | |
| CN114105117A (en) | Preparation method of precursor and nickel lithium iron phosphate cathode material |
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 |