CN113036134A - Preparation method of high-compaction-density and high-safety graded high-nickel single crystal ternary material - Google Patents

Preparation method of high-compaction-density and high-safety graded high-nickel single crystal ternary material Download PDF

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CN113036134A
CN113036134A CN202011585872.0A CN202011585872A CN113036134A CN 113036134 A CN113036134 A CN 113036134A CN 202011585872 A CN202011585872 A CN 202011585872A CN 113036134 A CN113036134 A CN 113036134A
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ternary material
single crystal
compaction
safety
nickel single
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唐淼
吕菲
徐宁
吴孟涛
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Tianjin B&M Science and Technology Co Ltd
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/62—Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
    • H01M4/628—Inhibitors, e.g. gassing inhibitors, corrosion inhibitors
    • 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
    • H01M4/50—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
    • H01M2004/026—Electrodes composed of, or comprising, active material characterised by the polarity
    • H01M2004/028—Positive electrodes
    • 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 high-compaction-density high-safety graded high-nickel single crystal ternary material and a preparation method and application thereof, wherein the preparation method comprises the following steps: 1) mixing the small-particle precursor, a lithium compound and a doped metal compound, and sintering to obtain a small-particle-size high-nickel single crystal material; 2) mixing the large-particle precursor, a lithium compound and a doped metal compound, and sintering to obtain a large-particle-size high-nickel single crystal material; 3) carrying out in-situ polymerization on large single crystal and small single crystal materials, a high molecular monomer and an initiator to form a cross-linked conductive high molecular protective layer on the surface; 4) and sintering at low temperature again to obtain the graded high-nickel single crystal ternary material with high compaction density and high safety. The gradation high nickel single crystal ternary material prepared by the invention has higher compaction density, high energy density and safety.

Description

Preparation method of high-compaction-density and high-safety graded high-nickel single crystal ternary material
Technical Field
The invention belongs to the field of lithium ion batteries, and particularly relates to a preparation method of a high-compaction-density and high-safety graded high-nickel single crystal ternary material.
Background
In recent years, the market of new energy automobiles in China is rapidly developed, and the continuously improved endurance mileage also puts higher and higher requirements on the energy density of power batteries.
The core of improving the energy density of the power battery lies in the development of a high-capacity anode material, the material with the highest capacity at present is a high-nickel ternary material, and the content of cobalt is reduced by increasing the content of nickel, so that the specific capacity of the material is improved. However, if the Ni content is too high, the service life and safety performance are reduced accordingly. Therefore, how to further increase the capacity of the positive electrode material without increasing the Ni content has been the focus of research.
Currently, increasing the charging voltage is one of the main approaches to increase the capacity of the cathode material. The theoretical specific capacity of the NCM622 or the NCM811 is about 274mAh/g, and the aim of increasing the capacity of the material can be achieved by increasing the charging voltage under the condition of not changing the Ni content of the material, for example, the capacity of the NCM622 at 4.3V is about 180mAh/g, but the capacity can reach 201mAh/g if the NCM622 or the NCM811 is charged to 4.5V.
The synthesis of the single crystal ternary material is one of effective methods for improving the discharge voltage, but the compaction density of the single crystal material is low, so that the practical use of the single crystal material is influenced. Therefore, there is a need to increase the packing density of single crystal materials. The improvement of the compaction density can be realized by methods such as the selection of the precursor, the adjustment of the sintering temperature, the matching of the large and small particles and the like.
Single crystal materials with blended large and small particles have been reported. Chinese patent CN104724763A adopts precursor lithium mixed salt with different particle sizes to directly synthesize large single crystal particles at the temperature higher than 900 ℃, then selects precursor lithium mixed with proper particle size to sinter into small single crystal particles, and then mixes and collocates to prepare the high compaction single crystal ternary material. Chinese patent CN109516509A also mixes small-particle single crystal ternary oxide, large-particle single crystal ternary oxide and lithium salt according to a preset proportion, then sinters and cools to obtain high-compaction single crystal ternary anode material, and CN110010889A adds a coating layer on the basis of size mixing.
However, in the prior art, a simple physical mixing grading method is adopted, and small particles are used for filling up the pores of large particles to obtain a high-compaction material. In the practical application process, after a period of operation, the electrolyte can gradually permeate into gaps of large and small particles, lithium dendrite is generated in situ, the large and small particles are separated, and the problem of powder breakage and the like is caused.
Disclosure of Invention
In view of the above, the present invention provides a method for preparing a graded high-nickel single crystal ternary material with high compaction density and high safety, which comprises in-situ synthesizing a high molecular polymer to form a high molecular polymer network, so as to closely link large and small particles, and the high molecular polymer network can also be flame retardant, thereby improving the safety of the material.
In order to achieve the purpose, the technical scheme of the invention is realized as follows:
a preparation method of a high-compaction-density and high-safety graded high-nickel single crystal ternary material comprises the following steps:
1) will D50Precursor Ni in the range of 2-6 mu m1-x-yCoxMny(OH)2Mixing a lithium source and a metal salt containing a metal element M according to a certain proportion, then roasting, crushing, washing, filtering, drying, screening and demagnetizing the roasted product to obtain the small-particle high-nickel single crystal ternary material LiNi1-x-yCoxMnyMzO2Wherein x is more than 0 and less than or equal to 0.2, y is more than 0.0 and less than or equal to 0.2, and z is more than 0 and less than or equal to 0.05, and D of the small-particle high-nickel single crystal ternary material50The particle size is 2-6 mu M, and M is at least one or two of Co, Mn, Al, Mg, Zn, V, Mo, W, Cu and Sn;
2) will D50Precursor Ni in the range of 2-6 mu m1-x-yCoxMny(OH)2Mixing a lithium source and a metal salt containing a metal element M' according to a certain proportion, then roasting, crushing, washing, filtering, drying, screening and demagnetizing the roasted product to obtain the large-particle high-nickel single crystal ternary material LiNi1-x-yCoxMnyMzO2(ii) a Wherein x is more than 0.0 and less than or equal to 0.2; y is more than 0.0 and less than or equal to 0.2, and y is more than or equal to 0z is less than or equal to 0.05, and D of the large-particle high-nickel single crystal ternary material50The particle size is 15-18 mu M, and M' is one or more of Sc, Ti, Sr, Y, Zr, Nb, Mo, W, Al, Mg, Zn, V, Sn, La, Ce, Nd and Er;
3) proportioning a large-particle high-nickel single crystal ternary material and a small-particle high-nickel single crystal ternary material according to a mass ratio of (5-9) to (1-5), stirring at a low speed in a mixer to form a mixture, transferring the mixture into a reaction kettle after uniformly mixing, adding a dispersing agent according to a mass ratio of 1: 5-10, and stirring to form a suspension;
4) adding a conductive polymer monomer into a dispersing agent to form a polymer suspension, dissolving an initiator in deionized water to form an initiator solution, dissolving a surfactant in deionized water to form a surfactant solution, slowly injecting the polymer suspension, the initiator solution and the surfactant solution into the suspension solution obtained in the step 3) by using a peristaltic pump, keeping the system at 0-5 ℃ after injection, and continuously stirring for 6-12 hours;
5) and (4) centrifuging, washing and drying the precipitate obtained in the step 4), roasting again, and granulating, crushing, screening and demagnetizing the roasted product to obtain the high-compaction-density high-safety graded high-nickel single crystal ternary material.
In the preparation process, the conductive polymer is initiated to polymerize in situ in the gaps between the large particles and the small particles, a conductive polymer network is formed among the large particles and the small particles, and the large particles and the small particles are better enveloped in the network.
In addition, the polymer network can also prevent the electrolyte from penetrating into the particles in the using process so as to form internal lithium dendrite and cause particle disintegration, and can also play a role in preventing the particles from contacting with the electrolyte to a certain extent, thereby improving the stability of the material.
Preferably, the lithium source in the step 1) and the step 2) is one or more of lithium hydroxide monohydrate, lithium carbonate, lithium nitrate, lithium oxide, lithium acetate and lithium oxalate, and the molar ratio of the lithium source to the precursor is (0.9-1.2): 1.
Preferably, the roasting conditions in the step 1) and the step 2) are as follows: the roasting temperature is 700-1000 ℃, the roasting time is 10-36 h, the roasting atmosphere is oxygen or air or a mixture of the oxygen and the air, and the flow rate of the sintering atmosphere is 6-50 m3/h。
Preferably, in the step 1) and the step 2), the metal salt accounts for 50-5000 ppm of the mass of the precursor.
Preferably, in the step 3) and the step 4), the dispersant is one or more of methanol, ethanol, Nitrogen Methyl Pyrrolidone (NMP) and toluene.
Preferably, in the step 4), the conductive polymer monomer is one of aniline, pyrrole, thiophene and 3, 4-ethoxy thiophene, and the mass concentration of the conductive polymer monomer in the polymer suspension is 1-20%; the initiator is one of ferric chloride, ammonium persulfate, potassium persulfate, sodium persulfate and hydrogen peroxide, and the mass concentration of the initiator in the initiator solution is 1-10%; the surfactant is any one of sodium dodecyl benzene sulfonate, hexadecyl trimethyl ammonium bromide, sodium polystyrene sulfonate, polyvinyl alcohol, polyvinylpyrrolidone and polyethylene glycol, and the mass concentration of the surfactant in the surfactant solution is 0.2-1%.
In the invention, the conductive polymer is used as a polymer network layer, so that the conductivity of the material can be improved; the initiator and the surfactant are thoroughly removed after high-temperature roasting, and do not remain in the material.
Preferably, in the step 4), the flow volume ratio of the polymer suspension, the initiator solution and the surfactant solution is controlled to be (8-10): 1-3): 0.5-1 by controlling the flow rate of the peristaltic pump, wherein the flow rate of the polymer suspension with the fastest flow rate is 20-40 ml/min-1。
Preferably, the adding proportion of the conductive high molecular monomer in the step 4) and the mixture in the step 3) is 5-15 mL: 100 g.
The polymer layer can not be too thick, and too thick can influence the mass transfer of material self, can effectual control polymer layer's thickness through the concentration and the velocity of flow of control polymer monomer.
Further, the roasting temperature in the step 4) is 100-200 ℃, and the roasting time is 1-2 hours.
The roasting temperature can effectively remove the initiator and the surfactant introduced in the in-situ polymerization process of the polymer, and simultaneously, the structure of a polymer network is not damaged.
The high-compaction-density and high-safety graded high-nickel single crystal ternary material prepared by the preparation method is applied to a lithium ion battery.
Compared with the prior art, the invention has the following advantages:
(1) in the invention, in the process of grading the large and small particles, in-situ high polymer polymerization is adopted to form a high polymer network to envelop the large and small particles, and simultaneously, the viscosity of the high polymer is utilized to better combine the large and small particles together to prevent the large and small particles from being separated in the actual process; meanwhile, the polymer network can also play a role in isolating the electrolyte, so that the stability of the material is improved; can effectively improve the cycle performance of the material, reduce the gas generation of the battery and improve the thermal stability of the material.
(2) Compared with the traditional spherical high-nickel ternary material, the material prepared by the method has lower specific surface area and stable structure, reduces the side reaction of the material and electrolyte, and can effectively prevent the gas generation of the battery. The gas production of the battery is reduced by 30 percent compared with the battery prepared by the prior material.
(3) The high nickel ternary gradation by using mixing granulation can have higher compaction density than the ternary gradation by using common size mixing: because the large and small particles are contacted more closely in the granulating process, the solid-phase reaction material has better fusion property and higher reaction degree. The energy density of the material is improved, and the compaction density of the single crystal material prepared by the invention reaches 3.65g/cm3。
Drawings
FIG. 1 is an SEM of the prepared material of example 1;
FIG. 2 is an SEM of a single crystal material in comparative example 1;
FIG. 3 is a P.D graph of example 1 and comparative example 1;
fig. 4 is a graph of the first discharge capacity of the button cell of example 1 and comparative example 1;
fig. 5 is a cycling graph of the button cell of example 1 and comparative example 1;
fig. 6 is a graph of the first discharge capacity of the button cell of example 2 and comparative example 2;
fig. 7 is a cycling graph of the button cell of example 2 and comparative example 2;
FIG. 8 is a DSC comparison of example 2 and comparative example 2.
Detailed Description
The present invention will be described in further detail with reference to specific examples. The starting materials used in the examples are, unless otherwise specified, commercially available from conventional sources.
Example 1
The preparation method of the high-compaction-density high-safety graded high-nickel single crystal ternary material comprises the following steps:
1) 1000g of D50＝3.6μm Ni0.8Co0.1Mn0.1(OH)2Precursor and 460g LIOH H2O and 3.52g ZrO2The additives are mixed uniformly by a high-speed mixer at 820 ℃ and 6m3Roasting for 20 hours in a box type furnace at the oxygen flow rate, and crushing by a mechanical crusher to obtain D50＝4.8μm LiNi0.8Co0.1Mn0.1A material.
2) 1000g of D50＝4.5μm Ni0.8Co0.1Mn0.1(OH)2Precursor and 468g LIOH H2O and 3.52g ZrO2Mixing the additives uniformly at 850 deg.C and 8m3Roasting the powder in a box furnace for 26h at the oxygen flow rate, and crushing the powder by a mechanical crusher to obtain D50＝17.5μm LiNi0.8Co0.1Mn0.1A material.
3) 800g D50＝17.5μm LiNi0.8Co0.1Mn0.1Single crystal ternary material and 200g D50＝4.8μm LiNi0.8Co0.1Mn0.1Single crystal ternary material is proportioned and mixedStirring at low speed in the machine to form a mixture, transferring the mixture to a reaction kettle after uniformly mixing, adding 5kg of ethanol, and stirring to form a suspension;
4) taking 100ml of aniline solution, using ethanol as a dispersing agent, preparing 10% aniline suspension, 5% ferric chloride solution and 0.5% sodium dodecyl benzene sulfonate solution according to mass concentration, slowly injecting the high molecular suspension, the initiator solution and the surfactant solution into the suspension solution formed in the step 3) by a peristaltic pump according to the flow volume ratio of 10:2:0.6, and controlling the flow rate of the aniline suspension to be 30 ml/min-1After the aniline suspension is injected, keeping the system at 3 ℃, and continuing stirring for 10 hours;
5) centrifuging, washing and drying the precipitate obtained in the step 4), roasting for 2h at 200 ℃ in an inert atmosphere, and granulating, crushing, screening and demagnetizing the roasted product to obtain the high-compaction-density high-safety graded high-nickel single crystal ternary material.
Comparative example 1
1) 1000g of D50＝3.6μm Ni0.8Co0.1Mn0.1(OH)2Precursor and 460g LIOH H2O and 3.52g ZrO2The additives are mixed uniformly by a high-speed mixer at 820 ℃ and 6m3Roasting for 20 hours in a box type furnace at the oxygen flow rate, and crushing by a mechanical crusher to obtain D50＝4.8μm LiNi0.8Co0.1Mn0.1A material.
2) 1000g D50＝4.8μm LiNi0.8Co0.1Mn0.1Transferring the single crystal ternary material into a reaction kettle, adding 5kg of ethanol, and stirring to form a suspension;
3) taking 100ml of aniline solution, using ethanol as a dispersing agent, preparing 10% aniline suspension, 5% ferric chloride solution and 0.5% sodium dodecyl benzene sulfonate solution according to mass concentration, slowly injecting the high molecular suspension, the initiator solution and the surfactant solution into the suspension solution formed in the step 2) by a peristaltic pump according to the flow volume ratio of 10:2:0.6, and controlling the flow rate of the aniline suspension to be 30 ml/min-1When aniline suspension is injectedAfter the completion of the addition, maintaining the system at 3 ℃, and continuing stirring for 10 hours;
4) centrifuging, washing and drying the precipitate obtained in the step 3), roasting for 2h at 200 ℃ in an inert atmosphere, and granulating, crushing, screening and demagnetizing the roasted product to obtain the high-compaction-density high-safety nickel single crystal ternary material.
That is, the size of the particles was not graded as compared with example 1.
Example 2
In this embodiment, the preparation method of the high-compaction-density high-safety graded high-nickel single crystal ternary material is as follows:
1) 1000g of D50＝3.8μm Ni0.88Co0.09Mn0.03(OH)2Precursor and 462g of LIOH. H2O and 1.27Y2O3Mixing the additives uniformly at 800 deg.C and 6m3Roasting for 20 hours in a box type furnace at the oxygen flow rate, and crushing by a mechanical crusher to obtain D50＝4.6μm LiNi0.88Co0.09Mn0.03O2A single crystal ternary material.
2) 1000g of D50＝4.2μm Ni0.8Co0.1Mn0.1(OH)2Precursor and 465g LIOH & H2O and 1.27Y2O3Mixing the additives uniformly at 830 deg.C and 8m3Roasting the powder in a box furnace for 26h at the oxygen flow rate, and crushing the powder by a mechanical crusher to obtain D50＝16.8μm LiNi0.88Co0.09Mn0.03O2A single crystal ternary material.
3) 700g D50＝16.8μm LiNi0.88Co0.09Mn0.03O2And 300g D50＝4.6μm LiNi0.88Co0.09Mn0.003O2Proportioning, stirring at low speed in a mixer to form a mixture, transferring the mixture into a reaction kettle after uniformly mixing, adding 5kg of ethanol, and stirring to form a suspension;
4) taking 100ml of pyrrole solution, taking ethanol as a dispersing agent, and concentrating according to the massPreparing 8% pyrrole suspension, 8% ammonium persulfate solution and 1% hexadecyl trimethyl ammonium bromide solution, slowly injecting the polymer suspension, the initiator solution and the surfactant solution into the suspension solution formed in the step 3) at a flow volume ratio of 9:3:1 by using a peristaltic pump, wherein the flow rate of the pyrrole suspension is controlled at 20 ml/min-1Keeping the system at 0 ℃ after the pyrrole suspension is injected, and continuing stirring for 12 hours;
5) centrifuging, washing and drying the precipitate obtained in the step 4), roasting for 2h at 200 ℃ in an inert atmosphere, and granulating, crushing, screening and demagnetizing the roasted product to obtain the high-compaction-density high-safety graded high-nickel single crystal ternary material.
Comparative example 2
1) 1000g of D50＝3.8μm Ni0.88Co0.09Mn0.03(OH)2Precursor and 462g of LIOH. H2O and 1.27Y2O3Mixing the additives uniformly at 800 deg.C and 6m3Roasting for 20 hours in a box type furnace at the oxygen flow rate, and crushing by a mechanical crusher to obtain D50＝4.6μm LiNi0.88Co0.09Mn0.03O2A single crystal ternary material.
2) 1000g of D50＝4.2μm Ni0.8Co0.1Mn0.1(OH)2Precursor and 465g LIOH & H2O and 1.27Y2O3Mixing the additives uniformly at 830 deg.C and 8m3Roasting the powder in a box furnace for 26h at the oxygen flow rate, and crushing the powder by a mechanical crusher to obtain D50＝16.8μm LiNi0.88Co0.09Mn0.03O2A single crystal ternary material.
3) 700g D50＝16.8μm LiNi0.88Co0.09Mn0.03O2And 300g D50＝4.6μm LiNi0.88Co0.09Mn0.003O2Proportioning, granulating, crushing, screening and demagnetizing to obtain the high-compaction-density high-safety graded high-nickel single crystal ternary material.
That is, compared with example 2, in-situ polymerization of a polymer was not performed.
Experimental conditions
FIGS. 1 and 2 are SEM images of materials prepared in example 1 and comparative example 1, and it can be seen from FIG. 1 that the material prepared in example 1 is D50The grain size was about 4.6 μm. The morphology of the material prepared in comparative example 1 was clearly less uniform than that of comparative example 1.
The finished product materials prepared in the above embodiments and comparative examples are used as the anode material of the lithium ion battery to assemble the CR2032 button battery, and the first discharge specific capacity of the button battery is tested by adopting a Land battery test system under the charge-discharge conditions of 0.2C and 25 ℃ within the voltage range of 2.5V-4.25V.
The test results are: the specific discharge capacity of 200.3mAh/g in the example 1 is tested by a pressure measuring powder densitometer, and the compaction density of the positive pole piece in the middle of the comparative example 1 is 3.65g/cm3And the compacted density is the area surface degree/(the density of the rolled pole piece-the thickness of the current collector). The test instrument is not changed, the material in the example 1 is made into a button cell, and the capacity retention rate of the button cell is tested to be 96.2% under the conditions of 45 ℃ and 50 weeks of 0.3C charge-discharge cycle.
The specific cubic capacity, compaction density and cycling performance of comparative example 1 were tested under the same conditions. The test results are: in comparative example 1, the discharge capacity of the material was 201.2mAh/g, the compacted density by a powder densitometer was 3.03g/cm3, the compacted density is area/(density after pole piece rolling-current collector thickness), the capacity retention rate of the button cell was 94.3% at 45 ℃ and 50 cycles of 0.3C charge and discharge, as shown in fig. 2.
The relevant experimental data in example 1 and comparative example 1 are shown in fig. 3,4, 5.
From the data of example 1 and comparative example 1, it can be seen that: although the discharge capacity of the material coated by the large and small grain compositions is reduced compared with that of the single small grain single crystal ternary material, the compact density comparison data of the positive pole piece can show that the large and small grain composition single crystal high nickel ternary material is obviously higher than the single grain high nickel ternary material, and the distribution of the large and small grain composition single crystal high nickel ternary material is more compact from the SEM morphology of figures 1 and 2. The manufacturing requirements of square, cylindrical and soft-package batteries with higher energy density can be met, and the method is applied to the fields of electric automobiles, energy storage power stations and the like.
By adopting the same test method, the graded single crystal high nickel ternary assembly obtained in the embodiment 2 is assembled into a CR2032 button cell, a Land cell test system is adopted to test the first discharge specific capacity of the button cell under the conditions of 2.5V-4.25V voltage, 25 ℃ and 0.2C charge and discharge, and the test result is as follows: the specific discharge capacity of the material in example 2 is 205.2mAh/g, while the specific discharge capacity of the material in comparative example 2 is 203.4mAh/g, as shown in FIG. 6, the specific discharge capacity of the material in example 2 is slightly higher, probably because the conductivity of the material is improved by the conductive polymer.
However, in terms of cycle, example 2 exhibited excellent stability, with a capacity retention rate of 93.6% at 50 cycles of 0.3C charge-discharge cycle, which was 3.8% higher than 89.8% of comparative example 2, as shown in fig. 7. This is strongly linked to the strength of the polymer network in terms of the attachment and stability of the large and small particles. In addition, the thermal stability of the material was further improved as shown in fig. 8. Full DSC testing showed an exotherm temperature of 224.3 deg.C for comparative example 2 and 232.5 deg.C for example 2, as shown in FIG. 8.
The results show that the formation of the in-situ polymer network effectively envelops the large and small particles, and simultaneously utilizes the viscosity of the polymer to better combine the large and small particles together, thereby preventing the large and small particles from being separated in the actual process and improving the electrochemical stability of the material; meanwhile, the polymer network can also effectively protect the material and improve the thermal stability of the material. So that the DSC exothermic peak temperature of the material is obviously improved.
The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims (10)

1. A preparation method of a high-compaction-density and high-safety graded high-nickel single crystal ternary material is characterized by comprising the following steps of: the method comprises the following steps:
1) will D50Precursor Ni in the range of 2-6 mu m1-x-yCoxMny(OH)2Mixing a lithium source and a metal salt containing a metal element M according to a certain proportion, then roasting, crushing, washing, filtering, drying, screening and demagnetizing the roasted product to obtain the small-particle high-nickel single crystal ternary material LiNi1-x-yCoxMnyMzO2Wherein x is more than 0 and less than or equal to 0.2, y is more than 0.0 and less than or equal to 0.2, and z is more than 0 and less than or equal to 0.05, and D of the small-particle high-nickel single crystal ternary material50The particle size is 2-6 mu M, and M is at least one or two of Co, Mn, Al, Mg, Zn, V, Mo, W, Cu and Sn;
2) will D50Precursor Ni in the range of 2-6 mu m1-x-yCoxMny(OH)2Mixing a lithium source and a metal salt containing a metal element M' according to a certain proportion, then roasting, crushing, washing, filtering, drying, screening and demagnetizing the roasted product to obtain the large-particle high-nickel single crystal ternary material LiNi1-x-yCoxMnyMzO2(ii) a Wherein x is more than 0.0 and less than or equal to 0.2; y is more than 0.0 and less than or equal to 0.2, z is more than or equal to 0 and less than or equal to 0.05, and D of the large-particle high-nickel monocrystal ternary material50The particle size is 15-18 mu M, and M' is one or more of Sc, Ti, Sr, Y, Zr, Nb, Mo, W, Al, Mg, Zn, V, Sn, La, Ce, Nd and Er;
3) proportioning a large-particle high-nickel single crystal ternary material and a small-particle high-nickel single crystal ternary material according to a mass ratio of (5-9) to (1-5), stirring at a low speed in a mixer to form a mixture, transferring the mixture into a reaction kettle after uniformly mixing, adding a dispersing agent according to a mass ratio of 1: 5-10, and stirring to form a suspension;
4) adding a conductive polymer monomer into a dispersing agent to form a polymer suspension, dissolving an initiator in deionized water to form an initiator solution, dissolving a surfactant in deionized water to form a surfactant solution, slowly injecting the polymer suspension, the initiator solution and the surfactant solution into the suspension solution obtained in the step 3) by using a peristaltic pump, keeping the system at 0-5 ℃ after injection, and continuously stirring for 6-12 hours;
5) and (4) centrifuging, washing and drying the precipitate obtained in the step 4), roasting again, and granulating, crushing, screening and demagnetizing the roasted product to obtain the high-compaction-density high-safety graded high-nickel single crystal ternary material.
2. The method for preparing the high-compaction-density high-safety graded high-nickel single-crystal ternary material according to claim 1, wherein the method comprises the following steps: the lithium source in the step 1) and the step 2) is one or more of lithium hydroxide monohydrate, lithium carbonate, lithium nitrate, lithium oxide, lithium acetate and lithium oxalate, and the molar ratio of the lithium source to the precursor is (0.9-1.2): 1.
3. The method for preparing the high-compaction-density high-safety graded high-nickel single-crystal ternary material according to claim 1, wherein the method comprises the following steps: the roasting conditions in the step 1) and the step 2) are as follows: the roasting temperature is 700-1000 ℃, the roasting time is 10-36 h, the roasting atmosphere is oxygen or air or a mixture of the oxygen and the air, and the flow rate of the sintering atmosphere is 6-50 m3/h。
4. The method for preparing the high-compaction-density high-safety graded high-nickel single-crystal ternary material according to claim 1, wherein the method comprises the following steps: in the step 1) and the step 2), the metal salt accounts for 50-5000 ppm of the mass of the precursor.
5. The method for preparing the high-compaction-density high-safety graded high-nickel single-crystal ternary material according to claim 1, wherein the method comprises the following steps: in the step 3) and the step 4), the dispersing agent is one or more of methanol, ethanol, N-methyl pyrrolidone (NMP) and toluene.
6. The method for preparing the high-compaction-density high-safety graded high-nickel single-crystal ternary material according to claim 1, wherein the method comprises the following steps: in the step 4), the conductive polymer monomer is one of aniline, pyrrole, thiophene and 3, 4-ethoxy thiophene, and the mass concentration of the conductive polymer monomer in the polymer suspension is 1-20%; the initiator is one of ferric chloride, ammonium persulfate, potassium persulfate, sodium persulfate and hydrogen peroxide, and the mass concentration of the initiator in the initiator solution is 1-10%; the surfactant is any one of sodium dodecyl benzene sulfonate, hexadecyl trimethyl ammonium bromide, sodium polystyrene sulfonate, polyvinyl alcohol, polyvinylpyrrolidone and polyethylene glycol, and the mass concentration of the surfactant in the surfactant solution is 0.2-1%.
7. The method for preparing the high-compaction-density high-safety graded high-nickel single-crystal ternary material according to claim 1, wherein the method comprises the following steps: in the step 4), the flow volume ratio of the polymer suspension, the initiator solution and the surfactant solution is controlled to be (8-10) to (1-3) to (0.5-1) by controlling the flow rate of the peristaltic pump, wherein the flow rate of the polymer suspension with the fastest flow rate is 20-40 ml/min-1。
8. The method for preparing the high-compaction-density high-safety graded high-nickel single-crystal ternary material according to claim 1, wherein the method comprises the following steps: the adding proportion of the conductive high molecular monomer in the step 4) and the mixture in the step 3) is 5-15 mL: 100 g.
9. The method for preparing the high-compaction-density high-safety graded high-nickel single-crystal ternary material according to claim 1, wherein the method comprises the following steps: the roasting temperature in the step 4) is 100-200 ℃, and the roasting time is 1-2 h.
10. The high-nickel single-crystal ternary material prepared by the preparation method according to any one of claims 1 to 9 is applied to a lithium ion battery.
CN202011585872.0A 2020-12-29 2020-12-29 Preparation method of high-compaction-density and high-safety graded high-nickel single crystal ternary material Pending CN113036134A (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114512645A (en) * 2021-12-29 2022-05-17 有研科技集团有限公司 High-nickel positive electrode material, preparation method thereof and lithium secondary battery

Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2006228733A (en) * 2005-02-15 2006-08-31 Samsung Sdi Co Ltd Cathode active material, its manufacturing method and cathode as well as lithium cell using the material
CN103811744A (en) * 2014-02-13 2014-05-21 北大先行科技产业有限公司 Method for preparing ternary positive electrode material of lithium ion battery
CN104332619A (en) * 2014-09-22 2015-02-04 上海中聚佳华电池科技有限公司 Polypyrrole- coated full-gradient cathode material and preparation method thereof
CN105655565A (en) * 2016-04-08 2016-06-08 苏州大学 Composite cathode material of sodium-ion battery and preparation method of composite cathode material
CN106986393A (en) * 2017-04-28 2017-07-28 格林美（无锡）能源材料有限公司 High voltage type cobalt acid lithium and preparation method thereof
CN109516509A (en) * 2018-11-16 2019-03-26 中伟新材料有限公司 A kind of high-pressure solid monocrystalline tertiary cathode material and preparation method thereof, application
CN109888235A (en) * 2019-03-06 2019-06-14 广东邦普循环科技有限公司 A kind of nickelic tertiary cathode material of gradation and its preparation method and application
CN110010889A (en) * 2019-04-17 2019-07-12 宁波容百新能源科技股份有限公司 A kind of nickelic positive electrode of high-pressure solid high stability and preparation method thereof and a kind of lithium ion battery
CN111370685A (en) * 2020-02-28 2020-07-03 江门市科恒实业股份有限公司 High-compaction-density single crystal ternary cathode material and preparation method thereof

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2006228733A (en) * 2005-02-15 2006-08-31 Samsung Sdi Co Ltd Cathode active material, its manufacturing method and cathode as well as lithium cell using the material
CN103811744A (en) * 2014-02-13 2014-05-21 北大先行科技产业有限公司 Method for preparing ternary positive electrode material of lithium ion battery
CN104332619A (en) * 2014-09-22 2015-02-04 上海中聚佳华电池科技有限公司 Polypyrrole- coated full-gradient cathode material and preparation method thereof
CN105655565A (en) * 2016-04-08 2016-06-08 苏州大学 Composite cathode material of sodium-ion battery and preparation method of composite cathode material
CN106986393A (en) * 2017-04-28 2017-07-28 格林美（无锡）能源材料有限公司 High voltage type cobalt acid lithium and preparation method thereof
CN109516509A (en) * 2018-11-16 2019-03-26 中伟新材料有限公司 A kind of high-pressure solid monocrystalline tertiary cathode material and preparation method thereof, application
CN109888235A (en) * 2019-03-06 2019-06-14 广东邦普循环科技有限公司 A kind of nickelic tertiary cathode material of gradation and its preparation method and application
CN110010889A (en) * 2019-04-17 2019-07-12 宁波容百新能源科技股份有限公司 A kind of nickelic positive electrode of high-pressure solid high stability and preparation method thereof and a kind of lithium ion battery
CN111370685A (en) * 2020-02-28 2020-07-03 江门市科恒实业股份有限公司 High-compaction-density single crystal ternary cathode material and preparation method thereof

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114512645A (en) * 2021-12-29 2022-05-17 有研科技集团有限公司 High-nickel positive electrode material, preparation method thereof and lithium secondary battery

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