CN110550635A - Preparation method of novel carbon-coated silica negative electrode material - Google Patents
Preparation method of novel carbon-coated silica negative electrode material Download PDFInfo
- Publication number
- CN110550635A CN110550635A CN201910868504.8A CN201910868504A CN110550635A CN 110550635 A CN110550635 A CN 110550635A CN 201910868504 A CN201910868504 A CN 201910868504A CN 110550635 A CN110550635 A CN 110550635A
- Authority
- CN
- China
- Prior art keywords
- ball milling
- negative electrode
- preparation
- electrode material
- placing
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B32/00—Carbon; Compounds thereof
- C01B32/05—Preparation or purification of carbon not covered by groups C01B32/15, C01B32/20, C01B32/25, C01B32/30
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B33/00—Silicon; Compounds thereof
- C01B33/113—Silicon oxides; Hydrates thereof
-
- 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
- H01M4/362—Composites
-
- 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
- H01M4/58—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
- H01M4/583—Carbonaceous material, e.g. graphite-intercalation compounds or CFx
- H01M4/587—Carbonaceous material, e.g. graphite-intercalation compounds or CFx for inserting or intercalating light metals
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2006/00—Physical properties of inorganic compounds
- C01P2006/40—Electric properties
-
- 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
- H01M2004/027—Negative 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 relates to a preparation method of a novel carbon-coated silica negative electrode material, which comprises the steps of crushing, crushing massive SiO into powder, preparing a mixed precursor, taking pitch and SiO, mixing in proportion, carrying out ball milling homogenization, carrying out carbonization coating, placing the mixed precursor obtained in the second step into a vacuum tube furnace, preparing a composite intermediate, carrying out ball milling homogenization, taking out the composite intermediate obtained in the third step, carrying out ball milling to obtain a homogeneous composite intermediate, carrying out carbonization coating, placing the composite intermediate obtained in the fourth step into the vacuum tube furnace again, introducing protective gas, and carrying out heat preservation for a certain time to obtain the carbon-coated silica composite negative electrode material. The method adopts a mode of combining segmented mechanical fusion and a carbon coating technology, achieves a good coating effect on SiO material particles, and the coated material has the advantages of high coulombic efficiency, good cycle performance, low cost, environmental friendliness and the like for the first time.
Description
Technical Field
The invention relates to a preparation method of a novel carbon-coated silica negative electrode material.
Background
With the development of science and technology and the increasing pollution caused by traditional petroleum energy, the demand of people for novel renewable energy is urgent day by day. The lithium ion battery has the advantages of good cycle stability, large energy density, long cycle life, environmental friendliness and the like, and thus becomes the most promising chemical energy source in the 21 st century and has gradually developed into the main body of the secondary battery market. Among them, the electrode material is one of the key factors determining the performance of the lithium ion battery. Because the reversible specific capacity of the anode material has small lifting space and the cathode material has great influence on the cycling stability and capacity of the battery, the lifting of the reversible specific capacity of the cathode material is the key for improving the energy density of the lithium ion battery at present.
However, the graphite electrode has low theoretical lithium storage capacity (LiC 6, 372mAh/g) and safety limit, so that the novel negative electrode material with high specific capacity, high charge-discharge efficiency, high cycle performance, good high-rate charge-discharge performance, high safety and low cost is very urgent to research and develop, becomes a hot topic in the research field of lithium ion batteries, and has very important significance for the development of the lithium ion batteries.
In the research of the novel non-carbon negative electrode material, the metal and alloy materials thereof, such as Si, Al, Mg, Sn and the like, which can be alloyed with Li are found, the reversible lithium storage capacity of the metal and alloy materials thereof is far higher than that of a graphite negative electrode, and silicon has the advantages of high theoretical lithium storage capacity (Li 22 Si 5, 4200mAh/g, which is more than ten times of that of the current commercial graphite negative electrode), a low de-intercalation lithium voltage platform, low electrolyte reaction activity, rich natural storage capacity, low price and the like, which is considered as one of the lithium ion battery negative electrode materials with the greatest development prospect.
Practical solutions for silicon-based cathodes can be divided into three main flow directions, namely nano silicon-carbon composites, silicon oxide-carbon composites and amorphous silicon alloys. The silicon carbon and silicon monoxide carbon composite material has been applied to a small range, but has a larger promotion space in the aspects of first effect, circulation and the like.
SiO has excellent electrochemical performance as a lithium ion battery cathode material, can form inactive phases Li 2 O and Li 4 SiO 4 in the process of lithium intercalation for the first time, and plays a certain role in relieving volume expansion, namely, the volume effect of the battery material is obviously reduced compared with that of a silicon material in the process of charging and discharging.
However, the inert lithium oxide and lithium silicate phases generated when SiO is first intercalated increase the first irreversible capacity loss, the coulombic efficiency of the first cycle is low, and during the subsequent charge and discharge processes, as a solid electrolyte phase interface (SEI) film is continuously generated, Li is consumed, and the coulombic efficiency is lower than 100%, the lithium-removable capacity of the negative electrode compared with the positive electrode in the actual battery is greatly reduced. And the electrical conductivity of the silicon oxide itself is also low. These are the main factors that limit the achievement of long life and high rate performance of silica as a negative electrode material during charge-discharge cycles.
In patent CN201210303878.3, silicon and silicon oxide are used as initial raw materials, and after ball milling, the initial raw materials are mixed with graphite, a conductive agent and asphalt to be spray-dried, to obtain spheroidal particles, and then carbonized and sintered to obtain a silicon-carbon composite negative electrode material.
CN103474631A discloses a silica composite negative electrode material, which comprises a silica matrix, a nano-silicon material uniformly deposited on the silica matrix, and a nano-conductive material coating layer on the surface of the silica/nano-silicon. The preparation method of the silicon monoxide composite negative electrode material comprises the steps of nano silicon chemical vapor deposition, nano conductive material coating modification, sieving and demagnetizing treatment. Although the specific capacity (>1600m Ah/g) and the first coulombic efficiency (> 80%) of the SiO composite material are improved to a certain extent. However, the silicon monoxide composite material is prepared by artificially introducing a nano silicon material with larger volume expansion on the surface of SiO particles in a physical combination mode on the basis of the original component structure of the SiO material, the crystal grain is larger and difficult to control, the dispersibility is poor, the problem of huge volume expansion caused by the Si material cannot be effectively buffered and cannot be avoided, and the cycle performance is poor.
In order to solve the above problems of SiO, the main solution is the nanocrystallization of SiO and the compounding with other materials, and at present, the compounding with carbon materials, such as amorphous carbon, graphite, graphene, carbon nanotubes, etc., is the most studied.
In view of the above, the present invention provides a method for simply preparing a carbon-coated doped silicon monoxide for preparing a lithium ion battery negative electrode material, which is simple in preparation process and high in yield, and can effectively solve the problems of low coulombic efficiency, short cycle life and low rate performance of the existing silicon monoxide as a negative electrode material in the charge-discharge cycle process.
Disclosure of Invention
In view of the defects of the prior art, the invention aims to provide a novel preparation method of a carbon-coated silica negative electrode material, and the silica negative electrode prepared by the method has the advantages of simple steps, low cost, high yield, high coulombic efficiency and good cycle performance.
In order to realize the above and other related objects, the invention provides a preparation method of a novel carbon-coated silica anode material, which comprises the steps of crushing a SiO massive body, crushing the massive SiO into powder by a crusher, screening the powder with proper granularity by a sample separation sieve, placing the powder in a ball milling tank, controlling the ball milling rotation speed to be 300-600rpm, the diameter of selected ball milling beads to be 6-10mm, and controlling the ball-material ratio to be 4-10:1, and carrying out wet ball milling for 2-8 h; secondly, preparing a mixed precursor, taking pitch and SiO, controlling the ratio of SiO to pitch to be 1:0.1-1, and after mixing, controlling the ball milling rotation speed to be 250-600rpm, the diameter of the selected ball milling beads to be 6-10mm, and the ball-to-material ratio to be 4-10:1 to perform wet ball milling for 2-6h to obtain the mixed precursor; thirdly, performing carbonization coating, namely placing the mixed precursor in the second step into a corundum square boat, then placing the corundum square boat into a vacuum tube furnace, introducing protective gas, heating to 800-1100 ℃ at the speed of 3-8 ℃/min, preserving heat for 1-4h, cooling to room temperature, performing ball milling granulation on the compound subjected to high-temperature carbonization, controlling the ball milling rotation speed to be 250-400rpm, selecting ball milling beads with the diameter of 6-10mm and controlling the ball-to-material ratio to be 4-10:1, and performing wet ball milling for 1-4h to obtain the carbon-coated silicon oxide composite negative electrode material; and fourthly, preparing an electrode, namely taking the powdery silicon monoxide composite negative electrode material, uniformly mixing the powdery silicon monoxide composite negative electrode material with a mixture of conductive carbon black and carbon nano tubes and styrene butadiene rubber according to the mass ratio of 90:5:5, coating the mixture on a copper foil current collector, and preparing a negative plate after vacuum drying, rolling and cutting.
Preferably, in the third step, the method comprises primary coating, ball milling homogenization, secondary coating carbonization and primary coating, wherein the mixed precursor in the second step is placed in a corundum ark, then the corundum ark is placed in a vacuum tube furnace, protective gas is introduced, the temperature is raised to the softening point of asphalt at the speed of 3-8 ℃/min, the temperature is kept for 1-4 hours, and then the mixture is naturally cooled to room temperature to obtain a composite intermediate; ball milling and homogenizing, taking out the composite intermediate obtained by primary coating, placing the composite intermediate in a ball milling tank, controlling the ball milling rotation speed to be 250-400rpm, selecting balls with the diameter of 6-10mm and the ball-material ratio to be 4-10:1, and carrying out wet ball milling for 1-4h to obtain the homogenized composite intermediate; and (3) secondary coating carbonization, placing the ball-milled and homogenized composite intermediate into a corundum square boat again, placing the corundum square boat into a vacuum tube furnace, introducing protective gas, heating to 900-plus 1100 ℃, preserving heat for 1-4h, cooling to room temperature, carrying out ball milling granulation on the cooled composite, controlling the ball milling rotation speed to 250-plus 400rpm, selecting ball milling beads with the diameter of 6-10mm, and controlling the ball-to-material ratio to be 4-10:1, and carrying out wet ball milling for 1-4h to obtain the carbon-coated silicon oxide composite negative electrode material.
Preferably, the milling medium is deionized water or alcohol in a wet ball milling process.
Preferably, in the first step, when the median diameter D50 of SiO is 0.1-1 μm, the preparation process of the second step is carried out.
Preferably, the molar ratio of O to Si in the bulk SiO is 0.85-1.15.
Preferably, the softening point of the pitch in the second step is 200-300 ℃ and the ash content is less than 0.05%.
Preferably, the vacuum drying temperature in the fourth step is 80 ℃.
Preferably, the protective gas is nitrogen or an inert gas.
In summary, the preparation method of the novel carbon-coated silica negative electrode material has the following beneficial effects: the good coating effect of the asphalt on the surface of silica material particles is successfully realized by adopting a mode of combining segmented mechanical fusion and carbonization coating technologies, the temperature is firstly raised to the softening point of the asphalt, the asphalt is uniformly treated after being softened and then is heated for carbonization coating, so that the asphalt is uniformly coated on the surface of the silica, the bonding strength of the asphalt and the silica is high, and the first coulomb efficiency and the cycle performance of the material are greatly improved; the coated material has high coulombic efficiency for the first time, breaks through the SiO theoretical efficiency and reaches 90 percent; low expansion rate, long service life, environmental protection, no pollution, low cost and easy large-scale production.
drawings
Fig. 1 is a scanning electron microscope image of 500 times magnification of the silica powder prepared by the method, which shows the overall distribution form of the silica negative electrode material powder.
FIG. 2 is a scanning electron microscope image of 10000 times magnification of the silica powder prepared by the method, which shows the surface morphology of a single particle of the silica negative electrode material.
FIG. 3 is a first charge-discharge curve of the silicon oxide composite material prepared by the method, wherein the first discharge (lithium intercalation) specific capacity of the material is 1679.6mAh/g, the charge (lithium deintercalation) specific capacity is 1527.3mAh/g, and the first charge-discharge efficiency reaches 90.1%.
FIG. 4 is a charge-discharge cycle efficiency curve of the SiOx composite material prepared by the method, wherein the reversible capacity retention rate reaches 81% after constant-current charge and discharge for 60 weeks at 0.1C under normal temperature, the black curve in the graph shows the reversible capacity retention rate of each cycle, and the calculation method is that the charging specific capacity of the cycle is divided by the charging specific capacity of the first cycle; the black discontinuity points represent the coulombic efficiency per cycle, and the calculation method is the charge specific capacity divided by the discharge specific capacity per cycle.
Detailed Description
Referring to fig. 1 to 4, the following embodiments are only described to help understand the method and the core idea of the present invention. It should be noted that, for those skilled in the art, it is possible to make various improvements and modifications to the present invention without departing from the principle of the present invention, and those improvements and modifications also fall within the scope of the claims of the present invention. The following description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The present invention will be described in further detail below with reference to specific embodiments thereof and the accompanying drawings.
Example 1
Weighing powder silicon monoxide (D50 is 0.1-1 μm) and asphalt (D50 is 0.4-1.3 μm) in a ball milling tank, controlling the mass ratio of the powder silicon oxide to the asphalt to be 1:0.17, adding deionized water and ball milling beads, controlling the ball-material ratio to be 6:1, the ball milling speed to be 500rpm, and the ball milling time to be 4 h. And ball milling and refining to obtain mixed precursor slurry.
Placing the refined mixed precursor slurry into a corundum square boat, placing the corundum square boat into a vacuum tube furnace, introducing protective gas, heating to 290 ℃ at the speed of 3 ℃/min, preserving heat for 2h, and naturally cooling to room temperature to obtain a composite intermediate. Taking out the composite intermediate, performing ball milling and refining, controlling the ball-material ratio to be 4:1, the ball milling rotation speed to be 300rpm, and the ball milling time to be 1.5h, thus obtaining the homogeneous composite intermediate.
Placing the homogenized composite intermediate into a corundum ark again, placing the corundum ark into a vacuum tube furnace, introducing protective gas, heating to 900 ℃, preserving heat for 2 hours, naturally cooling to room temperature, placing the cooled composite into a ball milling tank, and controlling the ball-material ratio to be 4:1, the ball milling rotation speed to be 300rpm, and the ball milling time to be 1.5 hours to obtain the carbon-coated silicon oxide composite negative electrode material.
Taking a powdery silicon monoxide composite negative electrode material, uniformly mixing the powdery silicon monoxide composite negative electrode material with a mixture of conductive carbon black and carbon nano tubes (the ratio of the conductive carbon black to the carbon nano tubes is 70:1) and styrene butadiene rubber according to a mass ratio of 90:5:5, coating the mixture on a copper foil current collector, drying the mixture for a certain time in vacuum at the temperature of 80 ℃, rolling and cutting the mixture into negative electrode sheets. The positive plate is a metal lithium plate and is assembled into the button cell. The charge and discharge test of the button cell is carried out on a LAND cell test system of Wuhanjinnuo electronic Co., Ltd, the constant current charge and discharge are carried out at 0.1C under the normal temperature condition, and the voltage range of a half cell is 2V-5 mV.
Example 2
Weighing powder silicon monoxide (D50 is 0.1-1 μm) and asphalt (D50 is 0.4-1.3 μm) in a ball milling tank, controlling the mass ratio of the powder silicon oxide to the asphalt to be 1:0.25, adding deionized water and ball milling beads, controlling the ball-material ratio to be 8:1, the ball milling speed to be 600rpm, and the ball milling time to be 3 h. And ball milling and refining to obtain mixed precursor slurry.
Placing the refined mixed precursor slurry into a corundum square boat, placing the corundum square boat into a vacuum tube furnace, introducing protective gas, heating to 300 ℃ at the speed of 5 ℃/min, preserving heat for 2 hours, and naturally cooling to room temperature to obtain a composite intermediate. Taking out the composite intermediate, performing ball milling and refining, controlling the ball-to-material ratio to be 6:1, the ball milling rotation speed to be 250rpm, and the ball milling time to be 2h, thus obtaining the homogeneous composite intermediate.
Placing the homogenized composite intermediate into a corundum ark again, placing the corundum ark into a vacuum tube furnace, introducing protective gas, heating to 1000 ℃, preserving heat for 1h, naturally cooling to room temperature, placing the cooled composite into a ball milling tank, and controlling the ball-to-material ratio to be 6:1, the ball milling rotation speed to be 250rpm, and the ball milling time to be 2h to obtain the carbon-coated silicon oxide composite negative electrode material.
Taking a powdery silicon monoxide composite negative electrode material, uniformly mixing the powdery silicon monoxide composite negative electrode material with a mixture of conductive carbon black and carbon nano tubes (the ratio of the conductive carbon black to the carbon nano tubes is 50:1) and styrene butadiene rubber according to a mass ratio of 90:5:5, coating the mixture on a copper foil current collector, drying the mixture for a certain time in vacuum at the temperature of 80 ℃, rolling and cutting the mixture into negative electrode sheets. The positive plate is a metal lithium plate and is assembled into the button cell. The charge and discharge test of the button cell is carried out on a LAND cell test system of Wuhanjinnuo electronic Co,
Under the condition of normal temperature, the constant current charging and discharging is carried out at 0.1C, and the voltage range of the half cell is 2V-5 mV.
Example 3
Weighing powder silicon monoxide (D50 is 0.1-1 μm) and asphalt (D50 is 0.4-1.3 μm) in a ball milling tank, controlling the mass ratio of the powder silicon oxide to the asphalt to be 1:0.30, adding deionized water and ball milling beads, controlling the ball-material ratio to be 7:1, the ball milling speed to be 400rpm, and the ball milling time to be 4 h. And ball milling and refining to obtain mixed precursor slurry.
Placing the refined mixed precursor slurry into a corundum square boat, placing the corundum square boat into a vacuum tube furnace, introducing protective gas, heating to 350 ℃ at the speed of 7 ℃/min, preserving heat for 3h, and naturally cooling to room temperature to obtain a composite intermediate. Taking out the composite intermediate, performing ball milling and refining, controlling the ball-material ratio to be 5:1, the ball milling rotation speed to be 350rpm, and the ball milling time to be 3h, thus obtaining the homogeneous composite intermediate.
Placing the homogenized composite intermediate into a corundum ark again, placing the corundum ark into a vacuum tube furnace, introducing protective gas, heating to 1100 ℃, preserving heat for 1h, naturally cooling to room temperature, placing the cooled composite into a ball milling tank, and controlling the ball-to-material ratio to be 5:1, the ball milling rotation speed to be 350rpm, and the ball milling time to be 3h to obtain the carbon-coated silicon oxide composite negative electrode material.
Taking a powdery silicon monoxide composite negative electrode material, uniformly mixing the powdery silicon monoxide composite negative electrode material with a mixture of conductive carbon black and carbon nano tubes (the ratio of the conductive carbon black to the carbon nano tubes is 60:1) and styrene butadiene rubber according to a mass ratio of 90:5:5, coating the mixture on a copper foil current collector, drying the mixture for a certain time in vacuum at the temperature of 80 ℃, rolling and cutting the mixture into negative electrode sheets. The positive plate is a metal lithium plate and is assembled into the button cell. The charge and discharge test of the button cell is carried out on a LAND cell test system of Wuhanjinnuo electronic Co., Ltd, the constant current charge and discharge are carried out at 0.1C under the normal temperature condition, and the voltage range of a half cell is 2V-5 mV.
Example 4
Weighing powder silicon monoxide (D50 is 0.1-1 μm) and asphalt (D50 is 0.4-1.3 μm) in a ball milling tank, controlling the mass ratio of the powder silicon oxide to the asphalt to be 1:0.4, adding deionized water and ball milling beads, controlling the ball-material ratio to be 6:1, the ball milling speed to be 300rpm and the ball milling time to be 4 h. And ball milling and refining to obtain mixed precursor slurry.
Placing the refined mixed precursor slurry into a corundum square boat, placing the corundum square boat into a vacuum tube furnace, introducing protective gas, heating to 300 ℃ at the speed of 6 ℃/min, preserving heat for 2 hours, and naturally cooling to room temperature to obtain a composite intermediate. Taking out the composite intermediate, performing ball milling and refining, controlling the ball-material ratio to be 4:1, the ball milling rotation speed to be 250rpm, and the ball milling time to be 2h, thus obtaining the homogeneous composite intermediate.
Placing the homogenized composite intermediate into a corundum ark again, placing the corundum ark into a vacuum tube furnace, introducing protective gas, heating to 800 ℃, preserving heat for 4 hours, naturally cooling to room temperature, placing the cooled composite into a ball milling tank, and controlling the ball-to-material ratio to be 4:1, the ball milling rotation speed to be 250rpm, and the ball milling time to be 2 hours to obtain the carbon-coated silicon oxide composite negative electrode material.
Taking a powdery silicon monoxide composite negative electrode material, uniformly mixing the powdery silicon monoxide composite negative electrode material with a mixture of conductive carbon black and carbon nano tubes (the ratio of the conductive carbon black to the carbon nano tubes is 80:1) and styrene butadiene rubber according to a mass ratio of 90:5:5, coating the mixture on a copper foil current collector, drying the mixture for a certain time in vacuum at the temperature of 80 ℃, rolling and cutting the mixture into negative electrode sheets. The positive plate is a metal lithium plate and is assembled into the button cell. The charge and discharge test of the button cell is carried out on a LAND cell test system of Wuhanjinnuo electronic Co., Ltd, the constant current charge and discharge are carried out at 0.1C under the normal temperature condition, and the voltage range of a half cell is 2V-5 mV.
Example 5
Weighing powder silicon monoxide (D50 is 0.1-1 μm) and asphalt (D50 is 0.4-1.3 μm) in a ball milling tank, controlling the mass ratio of the powder silicon oxide to the asphalt to be 1:0.5, adding deionized water and ball milling beads, controlling the ball-material ratio to be 5:1, the ball milling speed to be 450rpm, and the ball milling time to be 2 h. And ball milling and refining to obtain mixed precursor slurry.
Placing the refined mixed precursor slurry into a corundum square boat, placing the corundum square boat into a vacuum tube furnace, introducing protective gas, heating to 350 ℃ at the speed of 8 ℃/min, preserving heat for 1h, and naturally cooling to room temperature to obtain a composite intermediate. Taking out the composite intermediate, performing ball milling and refining, controlling the ball-material ratio to be 4:1, the ball milling rotation speed to be 300rpm, and the ball milling time to be 1h, thus obtaining the homogeneous composite intermediate.
Placing the homogenized composite intermediate into a corundum ark again, placing the corundum ark into a vacuum tube furnace, introducing protective gas, heating to 1100 ℃, preserving heat for 2 hours, naturally cooling to room temperature, placing the cooled composite into a ball milling tank, and controlling the ball-material ratio to be 4:1, the ball milling rotation speed to be 300rpm, and the ball milling time to be 1 hour to obtain the carbon-coated silicon oxide composite negative electrode material.
Taking a powdery silicon monoxide composite negative electrode material, uniformly mixing the powdery silicon monoxide composite negative electrode material with a mixture of conductive carbon black and carbon nano tubes (the ratio of the conductive carbon black to the carbon nano tubes is 80:1) and styrene butadiene rubber according to a mass ratio of 90:5:5, coating the mixture on a copper foil current collector, drying the mixture for a certain time in vacuum at the temperature of 80 ℃, rolling and cutting the mixture into negative electrode sheets. The positive plate is a metal lithium plate and is assembled into the button cell. The charge and discharge test of the button cell is carried out on a LAND cell test system of Wuhanjinnuo electronic Co., Ltd, the constant current charge and discharge are carried out at 0.1C under the normal temperature condition, and the voltage range of a half cell is 2V-5 mV.
Example 6
Weighing powder silicon monoxide (D50 is 0.1-1 μm) and asphalt (D50 is 0.4-1.3 μm) in a ball milling tank, controlling the mass ratio of the powder silicon oxide to the asphalt to be 1:0.8, adding deionized water and ball milling beads, controlling the ball-material ratio to be 9:1, the ball milling speed to be 280rpm and the ball milling time to be 3.5 h. And ball milling and refining to obtain mixed precursor slurry.
Placing the refined mixed precursor slurry into a corundum square boat, placing the corundum square boat into a vacuum tube furnace, introducing protective gas, heating to 350 ℃ at the speed of 6 ℃/min, preserving heat for 2 hours, and naturally cooling to room temperature to obtain a composite intermediate. Taking out the composite intermediate, performing ball milling and refining, controlling the ball-to-material ratio to be 9:1, the ball milling rotation speed to be 250rpm, and the ball milling time to be 2h, thus obtaining the homogeneous composite intermediate.
Placing the homogenized composite intermediate into a corundum ark again, placing the corundum ark into a vacuum tube furnace, introducing protective gas, heating to 1100 ℃, preserving heat for 2 hours, naturally cooling to room temperature, placing the cooled composite into a ball milling tank, and controlling the ball-to-material ratio to be 9:1, the ball milling rotation speed to be 250rpm, and the ball milling time to be 2 hours to obtain the carbon-coated silicon oxide composite negative electrode material.
Taking a powdery silicon monoxide composite negative electrode material, uniformly mixing the powdery silicon monoxide composite negative electrode material with a mixture of conductive carbon black and carbon nano tubes (the ratio of the conductive carbon black to the carbon nano tubes is 50:1) and styrene butadiene rubber according to a mass ratio of 90:5:5, coating the mixture on a copper foil current collector, drying the mixture for a certain time in vacuum at the temperature of 80 ℃, rolling and cutting the mixture into negative electrode sheets. The positive plate is a metal lithium plate and is assembled into the button cell. The charge and discharge test of the button cell is carried out on a LAND cell test system of Wuhanjinnuo electronic Co., Ltd, the constant current charge and discharge are carried out at 0.1C under the normal temperature condition, and the voltage range of a half cell is 2V-5 mV.
Example 7
Weighing powdery silicon oxide (D50 is 0.1-1 μm) and asphalt (D50 is 0.4-1.3 μm) in a ball milling tank, wherein the mass ratio of the powdery silicon oxide to the asphalt is 1:0.4, adding deionized water and ball milling beads, the ball-material ratio is 8:1, the ball milling speed is 400rpm, and the ball milling time is 4 hours. And ball milling and refining to obtain a mixed precursor.
Placing the refined mixed precursor into a corundum square boat, placing the corundum square boat into a vacuum tube furnace, introducing protective gas, heating to 900 ℃ at the speed of 5 ℃/min, preserving heat for 4h, naturally cooling to room temperature, placing the cooled compound into a ball milling tank, and controlling the ball-material ratio to be 8:1, the ball milling rotation speed to be 380rpm, and the ball milling time to be 1h to obtain the carbon-coated silicon oxide composite negative electrode material.
Taking a powdery silicon monoxide composite negative electrode material, uniformly mixing the powdery silicon monoxide composite negative electrode material with a mixture of conductive agent SP (conductive carbon black) and CNTS (carbon nano tube) (the ratio of the conductive carbon black to the carbon nano tube is 70:1) and a binder SBR (styrene butadiene rubber) according to the mass ratio of 90:5:5, coating the mixture on a copper foil current collector, and preparing a negative electrode sheet after vacuum drying, rolling and cutting pieces. The positive plate is a metal lithium plate and is assembled into the button cell. The charge and discharge test of the button cell is carried out on a LAND cell test system of Wuhanjinnuo electronic Co., Ltd, the constant current charge and discharge are carried out at 0.1C under the normal temperature condition, and the voltage range of a half cell is 2V-5 mV.
Example 8
Weighing powdery silicon oxide (D50 is 0.1-1 μm) and asphalt (D50 is 0.4-1.3 μm) in a ball milling tank, wherein the mass ratio of the powdery silicon oxide to the asphalt is 1:0.4, adding deionized water and ball milling beads, the ball-material ratio is 8:1, the ball milling speed is 400rpm, and the ball milling time is 4 hours. And ball milling and refining to obtain mixed precursor slurry.
Placing the refined mixed precursor slurry into a corundum square boat, placing the corundum square boat into a vacuum tube furnace, introducing protective gas, heating to 290 ℃ at a speed of 4 ℃/min, keeping the temperature for 2h, then continuing heating to 900 ℃, keeping the temperature for 2h, naturally cooling to room temperature, placing the cooled compound into a ball-milling tank, and controlling the ball-material ratio to be 8:1, the ball-milling rotation speed to be 280rpm, and the ball-milling time to be 2h to obtain the carbon-coated silicon monoxide composite negative electrode material.
Taking a powdery silicon monoxide composite negative electrode material, uniformly mixing the powdery silicon monoxide composite negative electrode material with a mixture of conductive agent SP (conductive carbon black) and CNTS (carbon nano tube) (the ratio of the conductive carbon black to the carbon nano tube is 70:1) and a binder SBR (styrene butadiene rubber) according to the mass ratio of 90:5:5, coating the mixture on a copper foil current collector, and preparing a negative electrode sheet after vacuum drying, rolling and cutting pieces. The positive plate is a metal lithium plate and is assembled into the button cell. The charge and discharge test of the button cell is carried out on a LAND cell test system of Wuhanjinnuo electronic Co., Ltd, the constant current charge and discharge are carried out at 0.1C under the normal temperature condition, and the voltage range of a half cell is 2V-5 mV.
Finally, the detection data of the silicon-oxygen composite negative electrode materials in the embodiments 1 to 8 are collected in the following table, wherein the yield is calculated by dividing the mass of the finally obtained negative electrode material by the total mass of the mixed dry materials before the first ball milling.
Table 1 shows values of respective parameters of the prepared anode materials
It can be seen that the first charge capacity of the partial composite negative electrode material prepared by the method reaches 1500mAh/g, the first coulombic efficiency reaches 90%, and after 50 weeks of circulation, the charge capacity retention rate is still about 80%. After the prepared carbon-coated silicon monoxide and graphite are compounded until the reversible capacity is 450mAh/g, a button cell is assembled and tested, and the capacity retention rate exceeds 80% after part of materials are circulated for 500 circles; meanwhile, the composite negative electrode material prepared by the method has the advantages of low expansion rate, long service life, low preparation cost, no pollution and the like, and is beneficial to large-scale production. Therefore, the invention overcomes various defects of the prior art and has high industrial utilization value and practical value.
The foregoing embodiments are merely illustrative of the principles and utilities of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or change the above-mentioned embodiments without departing from the spirit and scope of the present invention. Accordingly, it is intended that all equivalent modifications or changes which can be made by those skilled in the art without departing from the spirit and technical spirit of the present invention be covered by the claims of the present invention.
Claims (8)
1. A preparation method of a novel carbon-coated silica negative electrode material is characterized by comprising the following steps: firstly, crushing SiO block-shaped bodies, crushing the SiO block-shaped bodies into powder by using a crusher, screening the powder with proper granularity by using a sample separating sieve, placing the powder in a ball milling tank, controlling the ball milling rotation speed to be 300-600rpm, selecting balls with the diameter of 6-10mm and controlling the ball-material ratio to be 4-10:1, and carrying out wet ball milling for 2-8 h; secondly, preparing a mixed precursor, taking pitch and SiO, controlling the ratio of SiO to pitch to be 1:0.1-1, and after mixing, controlling the ball milling rotation speed to be 250-600rpm, the diameter of the selected ball milling beads to be 6-10mm, and the ball-to-material ratio to be 4-10:1 to perform wet ball milling for 2-6h to obtain the mixed precursor; thirdly, performing carbonization coating, namely placing the mixed precursor in the second step into a corundum square boat, then placing the corundum square boat into a vacuum tube furnace, introducing protective gas, heating to 800-plus-1100 ℃ at the speed of 3-8 ℃/min, preserving heat for 1-4h, cooling to room temperature, performing ball milling granulation on the compound subjected to high-temperature carbonization, controlling the ball milling rotation speed to be 250-plus-400 rpm, selecting the ball milling beads with the diameter of 6-10mm, and controlling the ball-to-material ratio to be 4-10:1, and performing wet ball milling for 1-4h to obtain the carbon-coated silicon oxide composite cathode material; and fourthly, preparing an electrode, namely taking the powdery silicon monoxide composite negative electrode material, uniformly mixing the powdery silicon monoxide composite negative electrode material with a mixture of conductive carbon black and carbon nano tubes and styrene butadiene rubber according to the mass ratio of 90:5:5, coating the mixture on a copper foil current collector, and preparing a negative plate after vacuum drying, rolling and cutting.
2. The preparation method of the novel carbon-coated silica negative electrode material according to claim 1, wherein the preparation method comprises the following steps: in the third step, primary coating, ball milling homogenization, secondary coating carbonization and primary coating are carried out, the mixed precursor in the second step is placed in a corundum ark, then the corundum ark is placed in a vacuum tube furnace, protective gas is introduced, the temperature is raised to the softening point of asphalt at the speed of 3-8 ℃/min, the temperature is kept for 1-4h, and then the mixed precursor is naturally cooled to the room temperature to obtain a composite intermediate; ball milling and homogenizing: taking out the composite intermediate obtained by primary coating, placing the composite intermediate in a ball milling tank, controlling the ball milling rotation speed to be 250-400rpm, selecting balls with the diameter of 6-10mm and the ball-material ratio to be 4-10:1, and carrying out wet ball milling for 1-4h to obtain a homogeneous composite intermediate; and (3) secondary coating carbonization, placing the ball-milled and homogenized composite intermediate into a corundum square boat again, placing the corundum square boat into a vacuum tube furnace, introducing protective gas, heating to 800-plus 1100 ℃, preserving heat for 1-4h, cooling to room temperature, carrying out ball milling granulation on the cooled composite, controlling the ball milling rotation speed to be 250-plus 400rpm, selecting ball milling beads with the diameter of 6-10mm and controlling the ball-to-material ratio to be 4-10:1, and carrying out wet ball milling for 1-4h to obtain the carbon-coated silicon oxide composite cathode material.
3. The method for preparing the novel coated silica anode material according to claim 1, wherein the method comprises the following steps: the ball milling medium is deionized water or alcohol in the wet ball milling process.
4. The preparation method of the novel carbon-coated silica negative electrode material according to claim 1, wherein the preparation method comprises the following steps: in the first step, when the median diameter D50 of SiO is 0.1-1 μm, the second step of the preparation process is carried out.
5. The preparation method of the novel carbon-coated silica negative electrode material according to claim 1, wherein the preparation method comprises the following steps: the molar ratio of O to Si in the bulk SiO is 0.85-1.15.
6. The preparation method of the novel carbon-coated silica negative electrode material according to claim 1, wherein the preparation method comprises the following steps: the softening point of the asphalt in the second step is 200-300 ℃, and the ash content is less than 0.05 percent.
7. The preparation method of the novel carbon-coated silica negative electrode material according to claim 1, wherein the preparation method comprises the following steps: in the fourth step, the vacuum drying temperature is 80 ℃.
8. The preparation method of the novel carbon-coated silica negative electrode material according to claim 1, wherein the preparation method comprises the following steps: the protective gas is nitrogen or inert gas.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910868504.8A CN110550635B (en) | 2019-09-15 | 2019-09-15 | Preparation method of novel carbon-coated silica negative electrode material |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910868504.8A CN110550635B (en) | 2019-09-15 | 2019-09-15 | Preparation method of novel carbon-coated silica negative electrode material |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN110550635A true CN110550635A (en) | 2019-12-10 |
| CN110550635B CN110550635B (en) | 2023-03-31 |
Family
ID=68740229
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910868504.8A Active CN110550635B (en) | 2019-09-15 | 2019-09-15 | Preparation method of novel carbon-coated silica negative electrode material |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110550635B (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111224105A (en) * | 2020-03-05 | 2020-06-02 | 上海纳米技术及应用国家工程研究中心有限公司 | Multi-stage carbon-coated and multi-time high-temperature-disproportionation-improved silicon-containing negative electrode material and preparation method and application thereof |
| CN113140714A (en) * | 2021-03-30 | 2021-07-20 | 苏州优源动力科技有限公司 | Method for producing silicon-oxygen cathode material by liquid phase coating and two-stage calcining method |
| CN113948683A (en) * | 2020-07-17 | 2022-01-18 | 河南省氟基新材料科技有限公司 | Silicon monoxide composite negative electrode material and preparation method and application thereof |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103474631A (en) * | 2013-10-08 | 2013-12-25 | 深圳市贝特瑞新能源材料股份有限公司 | Silicon monoxide composite negative electrode material for lithium ion battery, preparation method and lithium ion battery |
| CN103633295A (en) * | 2012-08-23 | 2014-03-12 | 上海杉杉科技有限公司 | Silicon-carbon composite material, lithium ion battery, and preparation method and application of silicon-carbon composite material |
| CN104022257A (en) * | 2014-06-16 | 2014-09-03 | 深圳市贝特瑞新能源材料股份有限公司 | Silicon dioxide composite anode material for lithium ion battery, as well as preparation method and application of silicon dioxide composite anode material |
| CN107623113A (en) * | 2017-09-08 | 2018-01-23 | 赣州市瑞富特科技有限公司 | A kind of porous long circulating silicon-carbon cathode material preparation method |
| CN108807870A (en) * | 2018-04-25 | 2018-11-13 | 福建翔丰华新能源材料有限公司 | A kind of preparation method of lithium-ion negative pole high power capacity composite material |
| CN109524650A (en) * | 2018-11-13 | 2019-03-26 | 东莞市凯金新能源科技股份有限公司 | A kind of lithium ion battery silicon monoxide composite cathode material and preparation method |
-
2019
- 2019-09-15 CN CN201910868504.8A patent/CN110550635B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103633295A (en) * | 2012-08-23 | 2014-03-12 | 上海杉杉科技有限公司 | Silicon-carbon composite material, lithium ion battery, and preparation method and application of silicon-carbon composite material |
| CN103474631A (en) * | 2013-10-08 | 2013-12-25 | 深圳市贝特瑞新能源材料股份有限公司 | Silicon monoxide composite negative electrode material for lithium ion battery, preparation method and lithium ion battery |
| CN104022257A (en) * | 2014-06-16 | 2014-09-03 | 深圳市贝特瑞新能源材料股份有限公司 | Silicon dioxide composite anode material for lithium ion battery, as well as preparation method and application of silicon dioxide composite anode material |
| CN107623113A (en) * | 2017-09-08 | 2018-01-23 | 赣州市瑞富特科技有限公司 | A kind of porous long circulating silicon-carbon cathode material preparation method |
| CN108807870A (en) * | 2018-04-25 | 2018-11-13 | 福建翔丰华新能源材料有限公司 | A kind of preparation method of lithium-ion negative pole high power capacity composite material |
| CN109524650A (en) * | 2018-11-13 | 2019-03-26 | 东莞市凯金新能源科技股份有限公司 | A kind of lithium ion battery silicon monoxide composite cathode material and preparation method |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111224105A (en) * | 2020-03-05 | 2020-06-02 | 上海纳米技术及应用国家工程研究中心有限公司 | Multi-stage carbon-coated and multi-time high-temperature-disproportionation-improved silicon-containing negative electrode material and preparation method and application thereof |
| CN113948683A (en) * | 2020-07-17 | 2022-01-18 | 河南省氟基新材料科技有限公司 | Silicon monoxide composite negative electrode material and preparation method and application thereof |
| CN113140714A (en) * | 2021-03-30 | 2021-07-20 | 苏州优源动力科技有限公司 | Method for producing silicon-oxygen cathode material by liquid phase coating and two-stage calcining method |
| CN113140714B (en) * | 2021-03-30 | 2022-04-15 | 苏州优源动力科技有限公司 | Method for producing silicon-oxygen cathode material by liquid phase coating and two-stage calcining method |
Also Published As
| Publication number | Publication date |
|---|---|
| CN110550635B (en) | 2023-03-31 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN110660984B (en) | Nano silicon-carbon composite material and preparation method and application thereof | |
| CN110556529A (en) | Cathode composite material with multilayer core-shell structure and preparation method and application thereof | |
| CN108346788B (en) | Preparation method of carbon-coated ferrosilicon composite negative electrode material | |
| CN110931764A (en) | Negative electrode material for lithium ion secondary battery, negative electrode sheet, and lithium ion secondary battery | |
| CN112133896B (en) | High-capacity graphite-silicon oxide composite material and preparation method and application thereof | |
| CN112968159A (en) | Silicon-based composite material, preparation method thereof, negative electrode material and lithium battery | |
| CN108365208B (en) | Preparation method of nano-silicon composite negative electrode material for lithium ion battery | |
| CN107093721A (en) | Graphite/silicon@carbon core shell structure compound dome negative materials and preparation method thereof | |
| CN108682787B (en) | Lithium ion battery pole piece and preparation method thereof | |
| CN110550635B (en) | Preparation method of novel carbon-coated silica negative electrode material | |
| CN112652758B (en) | Silicon oxide/carbon microsphere composite negative electrode material for lithium ion battery and preparation method thereof | |
| WO2022002057A1 (en) | Silicon-oxygen composite negative electrode material, negative electrode, lithium-ion battery, and preparation methods therefor | |
| CN113130858B (en) | Silicon-based negative electrode material, preparation method thereof, battery and terminal | |
| CN109704324A (en) | Electrode material and secondary battery | |
| CN111689500A (en) | Preparation method of low-expansibility SiO/graphite composite electrode material | |
| CN109148851B (en) | Silicon-carbon composite negative electrode material modified by double carbon structure and preparation method thereof | |
| CN111342014A (en) | Silicon-carbon negative electrode material of lithium ion battery and preparation method thereof | |
| CN112952048A (en) | Silicon-carbon composite negative electrode material, preparation method thereof, electrode and secondary battery | |
| CN111640916A (en) | Preparation method of lithium ion battery negative electrode material | |
| CN113206249A (en) | Lithium battery silicon-oxygen composite negative electrode material with good electrochemical performance and preparation method thereof | |
| WO2018113267A1 (en) | Negative electrode material for lithium ion battery and preparation method therefor | |
| CN115714170A (en) | Preparation method of high-energy-density fast-charging negative electrode material | |
| CN111162254A (en) | Preparation method of silicon-carbon composite negative electrode material | |
| CN110429272B (en) | Silicon-carbon composite negative electrode material with pitaya-like structure and preparation method thereof | |
| CN112670460A (en) | Silicon-carbon composite material, electrode, lithium ion battery and preparation method and application thereof |
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 |