CN111342024A - Long-cycle lithium manganate positive electrode material and preparation method thereof - Google Patents
Long-cycle lithium manganate positive electrode material and preparation method thereof Download PDFInfo
- Publication number
- CN111342024A CN111342024A CN202010179645.1A CN202010179645A CN111342024A CN 111342024 A CN111342024 A CN 111342024A CN 202010179645 A CN202010179645 A CN 202010179645A CN 111342024 A CN111342024 A CN 111342024A
- Authority
- CN
- China
- Prior art keywords
- lithium
- lithium manganate
- positive electrode
- long
- electrode material
- 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.)
- Pending
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
- H01M10/00—Secondary cells; Manufacture thereof
- H01M10/42—Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells
- H01M10/4235—Safety or regulating additives or arrangements in electrodes, separators or electrolyte
-
- 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
- H01M4/38—Selection of substances as active materials, active masses, active liquids of elements or alloys
- H01M4/46—Alloys based on magnesium or aluminium
- H01M4/463—Aluminium based
-
- 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
- H01M4/58—Selection of substances as active materials, active masses, active liquids of inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy; of polyanionic structures, e.g. phosphates, silicates or borates
- H01M4/5825—Oxygenated metallic salts or polyanionic structures, e.g. borates, phosphates, silicates, olivines
-
- 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
Abstract
The invention discloses a long-cycle lithium manganate positive electrode material and a preparation method thereof, wherein the long-cycle lithium manganate positive electrode material comprises the following steps: s1, mixing lithium salt, a trimanganese tetroxide precursor, phosphate and fluoride salt to obtain a mixed raw material A; s2, drying the mixed raw material A to obtain a mixed raw material B; s3, sintering the dried mixed raw material B to obtain a sintered product C; s4, performing jet milling on the sintered product C to obtain a primary sintered product D; s5, mixing the primary sintered product D with nano alumina to obtain a mixed raw material E; s6, sintering the mixed raw material E to obtain a sintered product F; and S7, performing jet milling on the sintered product F to obtain the material. According to the invention, the spherical or spheroidal manganous-manganic oxide precursor with controllable morphology is used, a proper amount of additive is added for bulk phase doping, and the obtained spherical lithium manganate is subjected to surface coating and other methods, so that the long-cycle lithium manganate positive electrode material with high crystallinity is obtained, and the defects of the prior art are overcome.
Description
Technical Field
The invention relates to the technical field of lithium ion battery preparation, in particular to a long-cycle lithium manganate positive electrode material and a preparation method thereof.
Background
With the development of the technology, the lithium ion battery has a very good application prospect in the fields of electric automobiles and energy storage, and will certainly have a profound influence on the life of people in the future. The lithium ion battery cathode material most widely used in commerce at present is LiCoO2However, LiCoO2Poor safety, environmental unfriendliness, and LiCoO due to the abundance of cobalt in earth crust of only 25ppm2It is expensive.
The spinel type lithium manganate is characterized by low price, environmental friendliness and good safety, and is regarded as one of the most promising positive electrode materials. The spinel type lithium manganate has a spinel structure, and the chemical formula of the lithium manganate with stoichiometric ratio is LiMn2O4The spinel lithium manganate belongs to a cubic system, is mainly prepared by a solid-phase synthesis method industrially, but in the calcining process, the internal precursor is difficult to completely react due to insufficient oxygen, so that the calcined spinel lithium manganate has poor crystal structure consistency and the morphology cannot be accurately controlled. The manganese element is continuously dissolved in the charge-discharge cycle process, so that the lithium manganate material has a structure collapse, irreversible capacity loss is formed, capacity attenuation is fast, and the cycle life is short. Researchers propose that the dissolution of manganese ions can be reduced by optimizing the composition of the lithium manganate raw material, properly performing surface coating, bulk phase doping and particle shape control methods, and improving the structural stability and cycle performance, but only stay in the research and test stage, and industrial application cannot be realized.
Chinese patent CN104319393B discloses a doping modification method of spinel type lithium manganate anode material, which comprises the following steps: compounding a lithium source, a salt doped with metal ions and citric acid into sol, adding manganous-manganic oxide powder into the sol, ball-milling and mixing, heating by microwave, calcining, ball-milling and performing heat treatment to obtain a target product, wherein the doped metal is Al, Ni, Cu, Mn,Co, Cr, Cu, Fe, Zr, and Y. According to the method, spherical or sphere-like manganous-manganic oxide is not adopted as a manganese source, so that the compacted density and the tap density are low, and the prepared LiMn is2O4The material property is general.
Chinese patent CN103825017A discloses a method for preparing lithium manganate used as a lithium ion battery anode material, which comprises the following steps: and mixing the manganous-manganic oxide and a lithium compound, sintering, doping aluminum oxide and magnesium oxide, and annealing to obtain the target product. The method has the defects that the gram capacity of the lithium manganate can be remarkably reduced by the aluminum oxide or the magnesium oxide, and finally, the performance of the lithium manganate cathode material has defects.
To stabilize LiMn2O4The structure of the material is generally realized by bulk phase doping in one-time sintering, namely, doping ions are placed in a bulk phase, so that the contact area of manganese and hydrofluoric acid can be reduced to a certain extent, but the reduction degree is low, and LiMn is macroscopically caused2O4The improvement of the structural stability of the material is not obvious, the existing problems can not be solved, and the technical effect is poor. There is also a related document that the contact area of manganese and hydrofluoric acid can be greatly reduced by means of surface coating, thereby effectively controlling the dissolution of manganese, which is macroscopically expressed as LiMn2O4The structural stability of the material is obviously improved, but when the surface is coated, the more successful coating material selected at present, such as nano aluminum hydroxide, can cause LiMn2O4The gram volume performance of the material is reduced, thereby creating a performance deficiency that is currently not overcome by an effective method.
Disclosure of Invention
The first invention of the present invention is directed to: in order to solve the problems, the preparation method of the long-cycle lithium manganate positive electrode material is provided, and the long-cycle lithium manganate positive electrode material with high crystallinity is obtained by using a spherical or spheroidal manganous-manganic oxide precursor with controllable morphology, adding a proper amount of additive to carry out bulk phase doping, carrying out surface coating, wet mixing, high-temperature sintering and other methods on the obtained spherical or spheroidal lithium manganate, so that the defects of the existing preparation method are overcome.
The second invention of the present invention is directed to: aiming at the existing problems, the lithium manganate anode material provided by the invention has high structural stability and high first coulombic efficiency in the circulation process, and solves the problems of low structural stability, fast capacity attenuation, short cycle life and the like of the existing lithium manganate anode material.
The technical scheme adopted by the invention is as follows: the preparation method of the long-cycle lithium manganate positive electrode material is characterized by comprising the following steps:
s1, mixing a lithium salt, a trimanganese tetroxide precursor, a phosphate and a fluoride salt according to a designed proportion, adding an ethanol solution, and uniformly mixing to obtain a mixed raw material A, wherein the phosphate is selected from one or more of ammonium phosphate, ammonium hydrogen phosphate and lithium phosphate, and the fluoride salt is lithium fluoride or/and aluminum fluoride;
s2, fully drying the mixed raw material A in a microwave dryer to obtain a dried mixed raw material B;
s3, placing the dry mixed raw material B in a track kiln for sintering to obtain a sintered product C;
s4, performing jet milling on the sintered product C to obtain a primary sintered product D;
s5, mixing the primary sintering product D with nano aluminum oxide or/and nano aluminum hydroxide to obtain a mixed raw material E;
s6, placing the mixed raw material E in a track kiln for sintering to obtain a sintered product F;
and S7, performing jet milling on the sintered product F to obtain the target product lithium manganate.
According to the preparation method, firstly, a spherical or sphere-like manganous-manganic oxide precursor is used as a manganese source, the shape of lithium manganate particles is effectively controlled to be spherical or sphere-like, the tap density and the compaction density of a lithium manganate positive electrode material are improved, the contact area of electrolyte and lithium manganate is further effectively reduced, the dissolution of manganese is effectively controlled, secondly, the traditional mode that doping ions such as nano aluminum oxide and nano aluminum hydroxide are doped during primary sintering is abandoned, the nano aluminum oxide or nano aluminum hydroxide is used for surface coating during secondary sintering, a conductive protective shell is further formed on the surfaces of the particles, the contact area of the electrolyte and the lithium manganate can be greatly reduced, the dissolution of manganese is inhibited, and the electrode material is protected from being corroded by hydrofluoric acid in the electrolyte. Meanwhile, in order to overcome the problems of capacity exertion reduction and conductivity reduction caused by nano aluminum oxide and nano aluminum hydroxide, the defects of capacity exertion can be compensated by doping phosphate and fluoride salt, such as ammonium phosphate, ammonium hydrogen phosphate, lithium fluoride, aluminum fluoride and the like, during primary sintering, so that the capacity exertion can be improved, the conductivity can be improved, the negative influence caused by doping nano aluminum oxide can be compensated, and under the comprehensive action, the long-cycle lithium manganate positive electrode material with high crystallinity is finally obtained, and the defects of the existing preparation process can be overcome.
In order to better implement the invention, in the invention, the mass percentages of the raw materials are as follows: 22-32% of lithium salt, 62-81% of manganous manganic oxide precursor, 0.8-1.5% of nano aluminum oxide or/and nano aluminum hydroxide, 0.5-2.5% of phosphate and 1.0-2.5% of fluoride, wherein the sum of the total mass percentages is 100%.
Further, the mass ratio of the lithium salt to the trimanganese tetroxide precursor is as follows: 1: (3.5-5.5).
In the invention, in step S1, the weighed raw materials are added into a ball milling tank, and wet ball milling is adopted to mix the raw materials, wherein the ball milling time is 2-4 h, and the ball milling rotation speed is 800-.
Alternatively, in step S1, the weighed raw materials are added into the ethanol solution, and the raw materials are mixed by magnetic stirring for 4-8 h, and then dried in an oven after the stirring.
Further, in step S3, the sintering atmosphere is oxygen, the pre-sintering temperature is 540-.
Further, in step S5, the weighed raw materials are added into a ball milling tank, and the raw materials are mixed by dry ball milling, wherein, agate balls are added as ball milling media according to 100-200% of the total weight of the materials, the ball milling time is 1-3 h, and the ball milling rotation speed is 800-2000 r/min.
Further, in step S6, the sintering atmosphere is air, the pre-sintering temperature is 300-450 ℃ during sintering, the temperature is kept for 4-6 h, then the temperature is increased to 500-650 ℃, the temperature is kept for 5-10 h, wherein the temperature increase rate is 10-15 ℃/min.
Further, in step S1, the ethanol solution is a mixed solution of ethanol and pure water, the concentration of ethanol is 40-60%, and the addition amount of the ethanol solution is 20-35% of the total mass of the raw materials.
The invention also discloses a long-cycle lithium manganate positive electrode material which is characterized by being prepared from the following raw materials in percentage by mass: 22-32% of lithium salt, 62-81% of manganous manganic oxide precursor, 0.8-1.5% of nano aluminum oxide or/and nano aluminum hydroxide, 0.5-2.5% of phosphate and 1-2.5% of fluoride, wherein the sum of the total mass percentages is 100%, the lithium salt is selected from one or more of lithium carbonate, lithium hydroxide, lithium oxalate and lithium acetate, the manganous manganic oxide precursor is spherical or spheroidal manganous manganic oxide, the phosphate is selected from one or more of ammonium phosphate, ammonium hydrogen phosphate and lithium phosphate, and the fluoride is lithium fluoride or/and aluminum fluoride.
In summary, due to the adoption of the technical scheme, the invention has the beneficial effects that:
1. according to the invention, a spherical or spheroidal manganous-manganic oxide precursor is used as a manganese source, the appearance of lithium manganate particles is effectively controlled to be spherical or spheroidal, so that the contact area of electrolyte and lithium manganate is effectively reduced, and meanwhile, nano aluminum oxide or nano aluminum hydroxide is used for surface coating during secondary sintering, so that a conductive protective shell is formed on the particle surface, thus the contact area of electrolyte and lithium manganate is greatly reduced, in addition, in order to overcome the problems of gram capacity exertion reduction and conductivity reduction caused by nano aluminum oxide or nano aluminum hydroxide, during primary sintering, the defects of the lithium manganate are compensated by doping phosphate and fluoride, the gram capacity exertion and the conductivity are improved, and under the comprehensive action, the long-cycle lithium manganate anode material with high crystallinity is finally obtained, and the defects of the existing preparation process are overcome;
2. the invention provides a long-cycle lithium manganate positive electrode material which is high in structural stability and high in first coulombic efficiency in a cycle process, and solves the problems of low structural stability, high capacity attenuation, short cycle life and the like of the conventional lithium manganate positive electrode material;
3. the preparation method disclosed by the invention is simple to operate, low in doped element content, cheap, low in preparation cost, large in profit margin, and easy to realize industrial production, and solves the problem that the preparation method only stays in an experimental research stage at present.
Drawings
FIG. 1 is a flow chart of the preparation method of the present invention;
FIG. 2 is a diagram showing the XRD test result of modified spinel type lithium manganate used in example 1 of the present invention;
FIG. 3 is a charge-discharge characteristic curve diagram of a lithium battery prepared from the lithium manganate cathode material provided in embodiment 1 of the present invention;
FIG. 4 is an SEM picture of a lithium manganate positive electrode material prepared in example 1 of the present invention;
fig. 5 is a charge-discharge cycle curve of the lithium manganate positive electrode material prepared in example 1 of the present invention.
Detailed Description
The present invention will be described in detail below with reference to the accompanying drawings.
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
Referring to fig. 1-3, a long-cycle lithium manganate cathode material is prepared from 22-32% of lithium salt, 62-81% of manganous oxide precursor, 0.8-1.5% of nano aluminum oxide or/and nano aluminum hydroxide, 0.5-2.5% of phosphate and 1-2.5% of fluoride, wherein the sum of the mass percentages of the above raw materials is 100%, wherein the phosphate is selected from one or more of ammonium phosphate, ammonium hydrogen phosphate and lithium phosphate, and the fluoride is lithium fluoride or/and aluminum fluoride.
In the above, the mass ratio of the lithium salt to the manganous-manganic oxide is: 1: (3.5-5.5). The lithium salt is selected from one of lithium carbonate, lithium hydroxide, lithium oxalate and lithium acetate, preferably lithium carbonate, and the trimanganese tetroxide precursor is spherical or spheroidal trimanganese tetroxide.
The preparation method of the long-cycle lithium manganate positive electrode material comprises the following steps:
s1, mixing 22-32% of lithium carbonate, 62-81% of manganous-manganic oxide precursor, 0.5-2.5% of phosphate and 1-2.5% of fluoride salt, adding an ethanol solution with the concentration of 50% and the total mass of 20-35%, and uniformly mixing to obtain a mixed raw material A;
s2, fully drying the mixed raw material A in a microwave dryer to obtain a dried mixed raw material B;
s3, placing the dry mixed raw material B in a track kiln for sintering to obtain a sintered product C;
s4, performing jet milling on the sintered product C to obtain a primary sintered product D;
s5, mixing the product D with 0.8-1.5% of nano aluminum oxide or nano aluminum hydroxide, adding the mixture into a ball mill for ball milling, and uniformly mixing to obtain a mixture raw material E;
s6, placing the mixture raw material E in an orbital kiln for sintering to obtain a sintered product F;
and S7, adding the sintered product F into a jet mill for crushing and grading, and finally obtaining the lithium manganate product.
In the step S1, the raw materials may be mixed by a conventional method, in the present invention, the step S1 is to uniformly mix the raw materials by wet ball milling, preferably, all the raw materials weighed in the step S1 are added into a ball milling tank, the ball milling time is 2-4 h, and the ball milling rotation speed is 800-.
In the above step S3, the sintering process and parameters may be conventional process and parameters, and in the present invention, the sintering atmosphere in the step S3 is preferably oxygen, and the sintering conditions are preferably: the presintering temperature is 540-.
In the step S5, a conventional mixing manner may also be adopted, in the present invention, the step S5 preferably adopts a dry ball milling method to mix the raw materials, specifically, the raw materials weighed in the step S5 are added into a ball milling tank, agate balls are added as ball milling media according to 100-.
In the step S6, the sintering atmosphere can be air, the pre-sintering temperature is 300-450 ℃ during sintering, the temperature is kept for 4-6 h, then the temperature is raised to 500-650 ℃, the temperature is kept for 5-10 h, wherein the temperature raising rate is 10-15 ℃/min.
In order to better carry out and illustrate the invention, specific examples are set forth below.
Example 1
A preparation method of a long-cycle lithium manganate positive electrode material comprises the following steps:
step 1, 113.506g of lithium carbonate, 453.902g of manganous manganic oxide precursor, 3.96g of ammonium hydrogen phosphate and 4.674g of lithium fluoride are mixed, ethanol solution (industrial alcohol) with the concentration of 50 percent and the total mass of 20-35 percent is added and mixed uniformly, the ball milling time is 3h, and the ball milling speed is 1500 r/min.
step 3, placing the dry mixed raw materials into a track kiln for sintering, wherein the sintering atmosphere is oxygen, the pre-sintering temperature is 550 ℃, the temperature is kept for 4 hours, then the temperature is raised to 810 ℃, the temperature is kept for 11 hours, and the temperature raising rate is 10 ℃/min;
step 5, mixing the primary sintered product with 5.09g of nano alumina, adding the mixture into a ball mill for ball milling, and uniformly mixing to obtain a mixture raw material; the ball milling time is 2h, and the ball milling rotating speed is 1200 r/min;
step 7, adding the sintered product into a jet mill for crushing and grading to obtain lithium manganate;
XRD characterization:
XRD characterization is carried out on the modified spinel type lithium manganate adopted in the embodiment 1 of the invention, as shown in figure 2, the modified spinel type lithium manganate is a pure phase spinel type lithium manganate with good crystallinity, good structural consistency and no other impurities.
And (3) testing the charge and discharge performance:
the mixed positive electrode material obtained in the embodiment 1 of the invention is prepared into a positive electrode sheet. In a glove box filled with high-purity argon, water and oxygen with concentration less than 0.1ppm, a metal lithium sheet is taken as a negative electrode, and a 2032 button battery is assembled according to the assembly sequence of a negative electrode shell, a lithium sheet, a diaphragm, electrolyte, a positive electrode sheet, a steel sheet, a shrapnel and a positive electrode shell. After being placed for 12h, the battery was tested for charge and discharge performance in a constant current mode, the charge limit voltage of the battery was 4.4V, and the discharge end voltage was 3V, with the test results shown in fig. 4 and 5.
According to the test result, the coulombic efficiency of the high-energy-density lithium manganate positive electrode material used as the positive electrode in the circulation process is close to 100%, the specific capacities of charging and discharging are about 125mAh/g when the charging and discharging current density is 14mA/g, the specific capacities of charging and discharging are about 122mAh/g when the charging and discharging current density is 28mA/g, and the capacity retention rate is 88.12% after the lithium manganate is circulated for 1000 cycles at 0.5C.
Therefore, the lithium battery taking the long-cycle lithium manganate anode material prepared by the technical scheme of the invention as the anode material has the advantages of high capacity, good long-cycle stability and the like in electrical properties.
Example 2
A preparation method of a long-cycle lithium manganate positive electrode material comprises the following steps:
step 1, 113.951g of lithium carbonate, 463.261g of manganous-manganic oxide precursor, 6.56g of ammonium hydrogen phosphate and 4.674g of lithium fluoride are mixed, ethanol solution (industrial alcohol) with the concentration of 50 percent and the total mass of 20-35 percent is added and mixed uniformly, the ball milling time is 3 hours, and the ball milling speed is 1500 r/min;
step 3, placing the dry mixed raw materials into a track kiln for sintering, wherein the sintering atmosphere is oxygen, the pre-sintering temperature is 550 ℃, the temperature is kept for 4 hours, then the temperature is raised to 815 ℃, the temperature is kept for 11 hours, and the temperature raising rate is 10 ℃/min;
step 5, mixing the primary sintered product with 5.09g of nano alumina, adding the mixture into a ball mill for ball milling, and uniformly mixing to obtain a mixture raw material, wherein the ball milling time is 2 hours, and the ball milling rotating speed is 1500 r/min;
and 7, adding the sintered product into a jet mill for air flow and classification treatment to obtain the lithium manganate.
Example 3
A preparation method of a long-cycle lithium manganate positive electrode material comprises the following steps:
step 1, 110.560g of lithium carbonate, 458.58g of manganous-manganic oxide precursor, 5.96g of ammonium hydrogen phosphate and 4.674g of lithium fluoride are mixed, ethanol solution (industrial alcohol) with the concentration of 50 percent and the total mass of 20-35 percent is added and mixed uniformly, the ball milling time is 3 hours, and the ball milling speed is 1500 r/min;
step 3, placing the dry mixed raw materials into a track kiln for sintering, wherein the sintering atmosphere is oxygen, the pre-sintering temperature is 550 ℃, the temperature is kept for 4 hours, then the temperature is increased to 820 ℃, the temperature is kept for 11 hours, and the temperature increasing rate is 10 ℃/min;
step 5, mixing the primary sintered product with 6.31g of nano alumina, adding the mixture into a ball mill for ball milling, and uniformly mixing to obtain a mixture raw material, wherein the ball milling time is 2 hours, and the ball milling rotating speed is 1200 r/min;
and 7, carrying out air flow crushing on the sintered product to obtain the lithium manganate.
According to the invention, a spherical or spheroidal manganous-manganic oxide precursor is used as a manganese source, the appearance of lithium manganate particles is effectively controlled to be spherical or spheroidal, the contact area of electrolyte and lithium manganate is further effectively reduced, and meanwhile, nano aluminum oxide is used for surface coating during secondary sintering, so that a conductive protective shell is formed on the particle surface, and thus, the contact area of electrolyte and lithium manganate is greatly reduced.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are intended to be included within the scope of the present invention.
Claims (10)
1. The preparation method of the long-cycle lithium manganate positive electrode material is characterized by comprising the following steps:
s1, mixing a lithium salt, a trimanganese tetroxide precursor, a phosphate and a fluoride salt according to a designed proportion, adding an ethanol solution, and uniformly mixing to obtain a mixed raw material A, wherein the phosphate is selected from one or more of ammonium phosphate, ammonium hydrogen phosphate and lithium phosphate, and the fluoride salt is lithium fluoride or/and aluminum fluoride;
s2, fully drying the mixed raw material A in a microwave dryer to obtain a dried mixed raw material B;
s3, placing the dry mixed raw material B in a track kiln for sintering to obtain a sintered product C;
s4, performing jet milling on the sintered product C to obtain a primary sintered product D;
s5, mixing the primary sintering product D with nano aluminum oxide or/and nano aluminum hydroxide to obtain a mixed raw material E;
s6, placing the mixed raw material E in a track kiln for sintering to obtain a sintered product F;
and S7, performing jet milling on the sintered product F to obtain the target product lithium manganate.
2. The preparation method of the long-cycle lithium manganate positive electrode material as claimed in claim 1, wherein the mass percentages of the raw materials are as follows: 22-32% of lithium salt, 62-81% of manganous manganic oxide precursor, 0.8-1.5% of nano aluminum oxide or/and nano aluminum hydroxide, 0.5-2.5% of phosphate and 1.0-2.5% of fluoride, wherein the sum of the total mass percentages is 100%.
3. The method for preparing the long-cycle lithium manganate positive electrode material as claimed in claim 2, wherein the mass ratio of the lithium salt to the trimanganese tetroxide precursor is: 1: (3.5-5.5).
4. The method for preparing a long-cycle lithium manganate positive electrode material as set forth in claim 2 or 3, wherein in step S1, the weighed raw materials are added into a ball milling tank, and wet ball milling is adopted to mix the raw materials, the ball milling time is 2-4 h, and the ball milling rotation speed is 800-.
5. The method for preparing the long-cycle lithium manganate positive electrode material as claimed in claim 2 or 3, wherein in step S1, the weighed raw materials are added into ethanol solution, the raw materials are mixed by magnetic stirring for 4-8 h, and after the stirring is finished, the mixture is placed in an oven for drying.
6. The method for preparing the long-cycle lithium manganate positive electrode material as set forth in claim 1, wherein in step S3, the sintering atmosphere is oxygen, the pre-sintering temperature is 540-.
7. The method for preparing the long-cycle lithium manganate positive electrode material as set forth in claim 1, wherein in step S5, the weighed raw materials are added into a ball-milling tank, and the raw materials are mixed by dry ball milling, wherein 100-.
8. The method for preparing the long-cycle lithium manganate positive electrode material as set forth in claim 1, wherein in step S6, the sintering atmosphere is air, the pre-sintering temperature is 300-.
9. The method for preparing a long-cycle lithium manganate positive electrode material as claimed in claim 1, wherein in step S1, said ethanol solution is a mixture of ethanol and pure water, the concentration of ethanol is 40-60%, and the amount of ethanol solution added is 20-35% of the total mass of raw materials.
10. The long-cycle lithium manganate cathode material is characterized by being prepared from the following raw materials in percentage by mass: 22-32% of lithium salt, 62-81% of manganous manganic oxide precursor, 0.8-1.5% of nano aluminum oxide or/and nano aluminum hydroxide, 0.5-2.5% of phosphate and 1-2.5% of fluoride, wherein the sum of the total mass percentages is 100%, the lithium salt is selected from one or more of lithium carbonate, lithium hydroxide, lithium oxalate and lithium acetate, the manganous manganic oxide precursor is spherical or spheroidal manganous manganic oxide, the phosphate is selected from one or more of ammonium phosphate, ammonium hydrogen phosphate and lithium phosphate, and the fluoride is lithium fluoride or/and aluminum fluoride.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010179645.1A CN111342024A (en) | 2020-03-16 | 2020-03-16 | Long-cycle lithium manganate positive electrode material and preparation method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010179645.1A CN111342024A (en) | 2020-03-16 | 2020-03-16 | Long-cycle lithium manganate positive electrode material and preparation method thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN111342024A true CN111342024A (en) | 2020-06-26 |
Family
ID=71187327
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010179645.1A Pending CN111342024A (en) | 2020-03-16 | 2020-03-16 | Long-cycle lithium manganate positive electrode material and preparation method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111342024A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113782721A (en) * | 2021-08-31 | 2021-12-10 | 深圳市泽塔电源系统有限公司 | Double-coated lithium manganate composite material and preparation method thereof |
| CN114314671A (en) * | 2022-01-07 | 2022-04-12 | 哈尔滨工业大学 | High-capacity lithium-manganese-oxygen-rich cathode material and preparation method thereof |
| CN114335507A (en) * | 2021-12-16 | 2022-04-12 | 安徽博石高科新材料股份有限公司 | Surface pressing type mixing and secondary sintering method of lithium battery positive electrode material |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102820462A (en) * | 2012-08-24 | 2012-12-12 | 安徽亚兰德新能源材料股份有限公司 | Preparation process of anode material lithium manganate of spherical structure for lithium ion battery |
| CN103107337A (en) * | 2012-04-01 | 2013-05-15 | 湖南大学 | Method for improving cycling stability of lithium ion battery anode material |
| CN108306010A (en) * | 2018-03-20 | 2018-07-20 | 陕西海恩新材料有限责任公司 | A kind of manganate cathode material for lithium and preparation method thereof |
| CN109768268A (en) * | 2019-03-16 | 2019-05-17 | 湖南海利锂电科技股份有限公司 | Manganate cathode material for lithium and preparation method thereof |
-
2020
- 2020-03-16 CN CN202010179645.1A patent/CN111342024A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103107337A (en) * | 2012-04-01 | 2013-05-15 | 湖南大学 | Method for improving cycling stability of lithium ion battery anode material |
| CN102820462A (en) * | 2012-08-24 | 2012-12-12 | 安徽亚兰德新能源材料股份有限公司 | Preparation process of anode material lithium manganate of spherical structure for lithium ion battery |
| CN108306010A (en) * | 2018-03-20 | 2018-07-20 | 陕西海恩新材料有限责任公司 | A kind of manganate cathode material for lithium and preparation method thereof |
| CN109768268A (en) * | 2019-03-16 | 2019-05-17 | 湖南海利锂电科技股份有限公司 | Manganate cathode material for lithium and preparation method thereof |
Non-Patent Citations (1)
| Title |
|---|
| Y.L.WANG: "Improvement of the high-rate discharge capability of phosphate-doped spinel LiMn2O4 by a hydrothermal method", 《ELECTROCHIMICA ACTA》 * |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113782721A (en) * | 2021-08-31 | 2021-12-10 | 深圳市泽塔电源系统有限公司 | Double-coated lithium manganate composite material and preparation method thereof |
| CN114335507A (en) * | 2021-12-16 | 2022-04-12 | 安徽博石高科新材料股份有限公司 | Surface pressing type mixing and secondary sintering method of lithium battery positive electrode material |
| CN114335507B (en) * | 2021-12-16 | 2024-02-20 | 安徽博石高科新材料股份有限公司 | Press-face type mixing and secondary sintering method for lithium battery anode material |
| CN114314671A (en) * | 2022-01-07 | 2022-04-12 | 哈尔滨工业大学 | High-capacity lithium-manganese-oxygen-rich cathode material and preparation method thereof |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN107394155B (en) | A kind of doping modification method of lithium cobalt oxide cathode material for lithium ion battery | |
| CN102881874B (en) | Method for preparing lithium-rich solid solution cathode material through reduction | |
| CN108493435B (en) | Lithium ion battery anode material Li (Ni)0.8Co0.1Mn0.1)1-xYxO2And preparation method | |
| CN110391407B (en) | Power battery positive electrode material with core-shell structure and preparation method and application thereof | |
| CN111342024A (en) | Long-cycle lithium manganate positive electrode material and preparation method thereof | |
| CN102983326A (en) | Spherical lithium-nickel-cobalt composite oxide positive electrode material preparation method | |
| CN108232182A (en) | A kind of modified nickel-cobalt lithium manganate cathode material and preparation method thereof | |
| CN113903907B (en) | Preparation method of tungsten-coated and doped monocrystal nickel-rich ternary cathode material | |
| CN105271424B (en) | Preparation method of needle-like spinel lithium manganese oxide positive electrode material | |
| CN114843469B (en) | MgFe 2 O 4 Modified P2/O3 type nickel-based layered sodium ion battery positive electrode material and preparation method thereof | |
| WO2023124574A1 (en) | Titanium and zirconium co-doped, carbon-coated lithium iron phosphate material, preparation method therefor and use thereof | |
| CN102723494A (en) | Doped and modified high-temperature lithium manganate cathode material and preparation method thereof | |
| CN113353995A (en) | Cathode material with low cobalt content and preparation method and application thereof | |
| CN108365216A (en) | The novel nickelic tertiary cathode material of one kind and preparation | |
| CN113517424A (en) | Cobalt-free positive electrode material of high-voltage lithium ion battery and preparation method thereof | |
| JP2024516477A (en) | Method for producing ferroboron alloy-coated lithium iron phosphate | |
| CN111834629A (en) | Cathode material, preparation method thereof and lithium ion battery | |
| CN105720242A (en) | Method for modifying lithium ion battery cathode material | |
| CN102881889B (en) | Method for preparing lithium-enriched solid solution cathode material by two-section direct temperature-rise sintering | |
| CN102881878B (en) | Method for preparing lithium-rich solid solution cathode material by virtue of metal reduction process | |
| CN103456945A (en) | Preparation method of low-cost lithium ion battery anode material | |
| CN111217395A (en) | High-energy-density lithium manganate cathode material and preparation method thereof | |
| CN113308736A (en) | Preparation method of doped cobalt-free single crystal lithium-rich manganese-based positive electrode material | |
| CN113149610A (en) | Preparation method of spinel type lithium battery positive electrode ceramic material based on interface regulation | |
| WO2023060992A1 (en) | Method for synthesizing high-safety positive electrode material by recycling positive electrode leftover materials, and application |
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 | ||
| RJ01 | Rejection of invention patent application after publication | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20200626 |