CN107785560B - High-performance silicon-carbon negative electrode material and preparation method thereof - Google Patents

High-performance silicon-carbon negative electrode material and preparation method thereof Download PDF

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CN107785560B
CN107785560B CN201711128166.1A CN201711128166A CN107785560B CN 107785560 B CN107785560 B CN 107785560B CN 201711128166 A CN201711128166 A CN 201711128166A CN 107785560 B CN107785560 B CN 107785560B
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silicon
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asphalt
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nano silicon
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CN107785560A (en
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李进
杨娟玉
卢世刚
曹宗双
赵春荣
于冰
史碧梦
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China Automotive Battery Research Institute Co Ltd
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Abstract

A high-performance silicon-carbon negative electrode material and a preparation method thereof are disclosed, wherein the preparation method comprises the following steps: (1) dispersing silicon in a solvent, performing liquid phase ball milling to obtain a nano silicon dispersion liquid, adding graphite, and performing liquid phase ball milling to realize uniform mixing of nano silicon and graphite; (2) granulating the slurry obtained by mixing in the step (1) to realize graphite/nano silicon composite granulation; (3) performing composite granulation on the product obtained in the step (2) and asphalt by adopting a kneading-pressing-crushing method, and performing mechanical fusion treatment to realize sphericization and uniform coating of the graphite/nano silicon/asphalt composite particles in one step; (4) and carbonizing, scattering and screening to obtain the high-performance silicon-carbon composite negative electrode material. The preparation method is simple, low in cost and easy for large-scale production of the high-performance silicon-carbon anode material.

Description

High-performance silicon-carbon negative electrode material and preparation method thereof
Technical Field
The invention belongs to the technical field of battery cathode materials, and particularly relates to a high-performance silicon-carbon cathode material and a preparation method thereof.
Background
Lithium ion batteries have been widely used in portable electronic devices, large-scale energy storage power stations, and electric vehicles because of their advantages of high operating voltage, long cycle life, no memory effect, small self-discharge effect, and environmental friendliness. At present, the commercial lithium ion battery cathode material mainly adopts graphite cathode materials, but the theoretical specific capacity is only 372mAh/g, and the requirements of future development of lithium ion batteries with higher specific energy and high power density cannot be met. Therefore, it is an important development direction to find a high specific capacity negative electrode material to replace carbon.
Due to the highest lithium storage capacity (the theoretical specific capacity is 4200mAh/g) and abundant resources, the silicon material is considered to have the most potential and is expected to become the negative electrode material of the next generation of lithium ion batteries. However, structural destruction of the silicon material and pulverization of the material due to a large volume change during intercalation/deintercalation of lithium may result in structural destruction of the electrode, resulting in loss of electrical contact of the silicon active component. In addition, the continuous generation of SEI film can be caused by the pulverization and huge volume change of the material, so that the electrochemical cycle stability of the battery is poor, and the large-scale application of the silicon material as the lithium ion battery cathode material is hindered.
In order to solve the problems of the silicon cathode material in application, researchers mainly reduce the absolute volume expansion of silicon by means of nano-crystallization of silicon and avoid pulverization of the material. But the problem of continuous generation of SEI film caused by electrochemical sintering and intensified side reaction of nano silicon in the circulation process cannot be solved by pure nano-crystallization. Therefore, it is necessary to solve various problems of silicon in practical application by constructing a multi-element multi-layer composite material by means of a combination of nano-fabrication and composite fabrication. Most of the silicon-carbon negative electrode materials reported at present are core-shell structures with surface coating treatment, the inner cores are loose and porous structures, and the porous structures maintain the appearance of the inner cores by providing spaces required by silicon expansion. However, the internal porosity of the structure is too large, which is beneficial to improving the cycling stability of the material, but the material is not pressure-resistant, the strength of the coating layer is low, the tap density of the material is low, and further the volume density of the battery is reduced, and under the same surface density condition, the performance of the battery is deteriorated due to the fact that the pole piece is too thick.
Therefore, in order to meet the development requirement of a new generation of high specific energy lithium ion battery, the capacity and tap density of the silicon-carbon negative electrode material and the surface density of a pole piece must be improved simultaneously.
For example, CN103682287A discloses a high-compaction-density silicon-based composite negative electrode material of a lithium ion battery with an embedded composite core-shell structure. The invention realizes the silicon coating by combining the mechanical grinding, the mechanical fusion, the isotropic pressure treatment and the carbon coating technologyAnd (3) preparing the carbon composite material. However, the method mentions that the process of preparing the hollow graphite by mechanical grinding is too ideal, and the graphite is easily crushed but not hollow in the actual process; the mechanical fusion process mainly realizes the dispersion of the nano silicon on the graphite surface, and carbon coating treatment is carried out in the later period; in addition, the breaking treatment after the isotropic pressure and high-temperature carbonization is easy to cause the damage of the surface coating layer, and the ideal core-shell structure cannot be achieved. CN103647056A discloses a SiOXThe invention adopts a mechanical fusion method to realize the nano carbon material in the SiO particlesXThe surface dispersion also needs further carbon coating treatment at the later stage.
Disclosure of Invention
Therefore, one of the purposes of the invention is to provide a preparation method of a high-performance silicon-carbon negative electrode material, wherein the negative electrode material prepared by the preparation method has high tap density, and the problems of thick pole piece and poor electrochemical performance of the silicon-carbon negative electrode material under the condition of high surface density are solved. The preparation method is simple, low in cost and easy for large-scale production of the high-performance silicon-carbon cathode material.
In order to achieve the purpose, the invention adopts the following technical scheme:
a preparation method of a high-performance silicon-carbon negative electrode material comprises the following steps:
(1) dispersing silicon in a solvent, performing liquid phase ball milling to obtain a nano silicon dispersion liquid, adding graphite, and performing liquid phase ball milling to realize uniform mixing of nano silicon and graphite;
(2) granulating the slurry obtained by mixing in the step (1) to realize graphite/nano silicon composite granulation, and simultaneously ensuring the uniform dispersion of nano silicon on the surface of graphite;
(3) performing composite granulation on the product obtained in the step (2) and asphalt by adopting a kneading-pressing-crushing method, and performing mechanical fusion treatment to realize sphericization and uniform coating of the graphite/nano silicon/asphalt composite particles in one step;
(4) and carbonizing, scattering and screening to obtain the high-performance silicon-carbon composite negative electrode material.
Compared with the prior art, the method utilizes the shaping effect of the mechanical fusion process at high rotating speed on the graphite/nano silicon/asphalt plastic composite particles to improve the sphericity and tap density of the material, wherein the asphalt is a continuous phase formed after melt kneading-pressing, but not a granular shape. In the process, the pitch is densely, uniformly and completely coated, the specific surface area of the material is reduced, an ideal core-shell structure silicon-carbon composite cathode material is successfully prepared, meanwhile, the carbon coating layer and the graphite/nano silicon core are tightly combined through a mechanical fusion process, the combination strength is increased, and a stable and effective transmission channel is provided for electron and lithium ion transmission.
Preferably, the silicon content of the raw material silicon used in step (1) is not less than 99%.
Preferably, the raw material silicon is micron silicon powder, preferably silicon powder with the median particle size of 1-5 μm, and more preferably silicon powder with the median particle size of 3 μm.
Preferably, the solvent is a combination of 1 or 2 or more of ethanol, methanol, isopropanol, n-butanol, acetone, toluene, and the like.
Preferably, the mass ratio of the raw material silicon to the solvent is 1:5 to 15, preferably 1: 9.
Preferably, the ball milling media are zirconia balls, preferably zirconia balls with a diameter of 0.1-0.5mm, and more preferably zirconia balls with a diameter of 0.3 mm.
Preferably, the mass ratio of ball materials subjected to ball milling in the preparation of the nano silicon dispersion is 5-15:1, preferably 10: 1.
Preferably, the rotation speed of ball milling during the preparation of the nano-silicon dispersion is 1500-.
Preferably, the mass ratio of graphite to the raw material silicon used is 1-3:1, preferably 1.7: 1.
Preferably, the rotation speed of the ball milling after adding the graphite is 500-1500rpm, preferably 1000rpm, and the time of the ball milling is more than 0.5 hour, preferably 1 hour. The rotation speed of ball milling after adding the graphite is preferably lower than that of ball milling in preparing the nano silicon dispersion liquid.
Preferably, the ball-to-feed ratio of the ball mill after adding the graphite is controlled to be 3:1-15: 1.
The ball milling may be performed using an ultra-fine ball mill.
Preferably, the granulation in step (2) is performed by spray drying.
Preferably, the graphite/nano silicon/asphalt composite granulation process in the step (3) comprises the following steps: hot mixing and kneading the product obtained in the step (2) and asphalt, then hot rolling, cooling and crushing into a powder material; then, isostatic pressing is carried out on the powder material to obtain a graphite/nano silicon/asphalt block green compact; the green body is then crushed and sieved.
Preferably, the asphalt is coal asphalt or petroleum asphalt having a softening temperature of 60 ℃ or higher.
Preferably, the mass ratio of the product obtained in step (2) to the asphalt is 1-4:1, preferably 2: 1.
Preferably, the temperature of the hot kneading is 100-.
Preferably, the temperature of the hot rolling is 100-300 ℃, preferably 120-250 ℃. The temperature of the hot rolling and the temperature of the hot kneading may be the same or different, and preferably the same. The film can be hot-rolled into a film package of about 2mm thickness.
Isostatic pressing may be performed on an isostatic press with the material placed in a rubber sheath.
Preferably, the pressure at the time of isostatic pressing is 150-300MPa, preferably 200MPa, and the time of isostatic pressing is 5min or more, preferably 10 min.
The porosity of the material can be controlled by controlling the mixing and kneading and pressing process parameters.
Preferably, the linear velocity during mechanical fusion is 10-50m/s, and the time for mechanical fusion is 3-60min, preferably 15-30 min. The mechanical fusion may be performed in a mechanical fusion machine.
With the increase of the mechanical fusion linear velocity and the fusion time, the sphericity and tap density of the material are increased. The linear velocity during mechanical fusion is selected to be 10-50m/s, and the mechanical fusion time is 3-60min, so that the sphericity and tap density of the material can be optimal.
The carbon coating layer of the graphite/nano silicon/asphalt composite particles prepared by the process is compact, high in strength and good in uniformity, the thickness of the carbon coating layer is controlled to be 0.05-2 mu m, and the thickness of the coating layer is controlled by changing the addition amount of asphalt.
In a preferred embodiment, the process of step (3) is: taking 2kg of the powdery intermediate product obtained by spray drying and 1kg of modified asphalt, and carrying out hot kneading for 2h at the temperature of 160-180 ℃; hot rolling the kneaded product at 160-180 ℃ to obtain a rubber package with the thickness of about 2mm, and crushing the rubber package into a powder material after cooling; then putting the powder material into a rubber sheath, and carrying out isostatic pressing for 10 minutes under the pressure of 200MPa in an isostatic press to obtain a graphite/nano silicon/asphalt blocky green compact; and then crushing and sieving the formed graphite/nano silicon/asphalt green compact, and mechanically fusing for 20min in a mechanical fusion machine at a linear speed of 45m/s to obtain graphite/nano silicon/asphalt composite particles.
Preferably, the carbonization in the step (4) is carried out under the protection of inert atmosphere, the carbonization temperature is 800-1000 ℃, preferably 900 ℃, and the carbonization time is more than 2h, preferably 4 h.
The silicon content in the silicon-carbon composite negative electrode material is 20-40%.
One of the purposes of the invention is to provide a high-performance silicon-carbon negative electrode material prepared by the method.
The preparation method adopts a mechanical fusion process, utilizes the characteristic that the graphite/nano silicon/asphalt composite precursor particles have certain plasticity, and realizes the sphericization of the graphite/nano silicon/asphalt composite precursor particles and the complete coating of asphalt by one step under the action of shearing force and extrusion force; greatly improves the tap density of the material and forms a compact and uniform coating layer on the surface.
Through the mechanical fusion process, the tight combination of the carbon coating layer and the graphite/nano silicon core is realized, the combination strength is increased, and a stable and effective transmission channel is provided for the transmission of electrons and lithium ions. Asphalt inside the particles is cracked to form a three-dimensional network conductive structure, and the three-dimensional network conductive structure has better strength, so that the internal conductivity of the material and the structural stability of the particles are improved.
The nano-silicon is uniformly dispersed on the surface of graphite or in pores of a graphite sheet layer, and the stability of a core structure and a conductive network is kept through three-dimensional asphalt cracking carbon with certain strength, so that good cycle stability and rate capability are achieved.
The silicon-carbon composite material prepared by the preparation method has high capacity and good cycle stability; the material has high tap density and excellent processing performance; a compact carbon coating layer is formed, so that the specific surface area of the material is reduced, the side reaction of electrolyte degradation is inhibited, and the coulomb efficiency of the silicon-carbon composite material is improved; compared with the traditional process, the method has the advantage that the yield of the material is higher and can reach more than 95%.
Drawings
FIG. 1 is a process flow diagram of the preparation method of the present invention;
FIG. 2 is an SEM image of a silicon carbon composite prepared in example 1;
FIG. 3 is a sectional SEM photograph of a silicon-carbon composite prepared in example 1;
FIG. 4 is a particle size distribution curve of the silicon carbon composite prepared in example 1;
FIG. 5 is a constant current charge and discharge curve of the silicon carbon composite prepared in example 1;
FIG. 6 is a graph of the cycling stability of the silicon carbon composite prepared in example 1;
FIG. 7 is an SEM image of the G/Si @ C silicon carbon composite of comparative example 1 without mechanofusion treatment.
Detailed Description
For the purpose of facilitating an understanding of the present invention, the present invention will now be described by way of examples. It should be understood by those skilled in the art that the examples are only for the purpose of facilitating understanding of the present invention and should not be construed as specifically limiting the present invention.
FIG. 1 is a process flow diagram of the preparation method of the present invention.
Example 1:
adding 2kg of micron silicon powder with the median particle size of 3 mu m and the silicon content of more than 99 percent into 18kg of ethanol solvent, performing ultrasonic dispersion for 30min, and pouring into a cavity of an ultrafine ball mill. Zirconia balls with the diameter of 0.3mm are used as ball milling media, the ball-material ratio (mass ratio) is 10:1, and ball milling is carried out for 10 hours at the rotating speed of 1800rpm, so as to obtain the nano silicon dispersion liquid. Adding 3.4kg of flake graphite into the nano-silicon dispersion liquid, and performing ball milling dispersion for 1 hour at the rotating speed of 1000rpm to obtain uniform mixed slurry. And (4) carrying out spray drying on the mixed slurry to obtain granular composite powder.
Taking 2kg of the powdery intermediate product obtained by spray drying and 1kg of modified asphalt, and carrying out hot kneading for 2h at the temperature of 160-180 ℃; hot rolling the kneaded product at 160-180 ℃ to obtain a rubber package with the thickness of about 2mm, and crushing the rubber package into a powder material after cooling; then putting the powder material into a rubber sheath, and carrying out isostatic pressing for 10 minutes under the pressure of 200MPa in an isostatic press to obtain a graphite/nano silicon/asphalt blocky green compact; then crushing and sieving the formed graphite/nano silicon/asphalt green compact, and mechanically fusing the graphite/nano silicon/asphalt green compact for 20min in a mechanical fusion machine at a linear speed of 45m/s to obtain graphite/nano silicon/asphalt composite particles; calcining for 4 hours at 900 ℃ under the protection of inert atmosphere; and scattering and screening to obtain the silicon-carbon composite negative electrode material with the silicon content of 33%.
Fig. 2 is an SEM (scanning electron microscope) image of the silicon-carbon composite negative electrode material prepared in this example, and it can be seen that the silicon-carbon composite material has better sphericity and smooth surface. Fig. 3 is an SEM image of a cross section of the silicon-carbon composite negative electrode material prepared in this embodiment, and it can be seen that nano-silicon is uniformly dispersed on the surface of graphite, pores exist between graphite sheets, a space is reserved for the volume expansion of silicon, and the surface of the material is coated with a dense amorphous carbon layer with a thickness of several hundred nanometers. Fig. 4 shows the particle size distribution of the silicon carbon composite material, with the median particle size of the material around 13 μm.
Table 1 shows the results of the performance tests of the materials prepared in this example. As can be seen from Table 1, the material has a small specific surface area of up to 2.4m2The material shows higher tap density reaching 0.96g/cm3. Fig. 5 and 6 are a first cycle charge-discharge curve and a cycle stability curve of the silicon-carbon composite negative electrode material, respectively. It can be seen that the reversible capacity of the silicon-carbon composite material in the first week is 857mAh/g, the coulomb efficiency in the first week is 83.7%, and the retention rate of the circulating capacity in 50 weeks is 75.9%.
FIG. 7 shows comparative example 1 in which no mechanofusion was usedThe SEM image of the silicon-carbon composite material prepared by the process shows that the material has poor sphericity, is in a random granular shape and has incomplete surface coating. As can be seen from Table 1, the tap density of the material is only 0.63g/cm3Specific surface area 6.7m2The tap density is low and the specific surface area is large.
Example 2:
adding 2kg of micron silicon powder with the median particle size of 3 mu m and the silicon content of more than 99 percent into 18kg of ethanol solvent, performing ultrasonic dispersion for 30min, and pouring into a cavity of an ultrafine ball mill. Zirconia balls with the diameter of 0.3mm are used as ball milling media, the ball-material ratio (mass ratio) is 10:1, and ball milling is carried out for 10 hours at the rotating speed of 1800rpm, so as to obtain the nano silicon dispersion liquid. Adding 3.4kg of flake graphite into the nano-silicon dispersion liquid, and performing ball milling dispersion for 1 hour at the rotating speed of 1000rpm to obtain uniform mixed slurry. And (4) carrying out spray drying on the mixed slurry to obtain granular composite powder.
Taking 2kg of the powdery intermediate product obtained by spray drying and 1kg of modified coal pitch, and carrying out hot kneading for 2h at the temperature of 120-140 ℃; hot rolling the kneaded product at the temperature of 120-140 ℃ to obtain rubber packing with the thickness of about 2mm, and crushing the rubber packing into a powder material after cooling; then putting the powder material into a rubber sheath, and carrying out isostatic pressing for 10 minutes under the pressure of 200MPa in an isostatic press to obtain a graphite/nano silicon/asphalt blocky green compact; then crushing and sieving the formed graphite/nano silicon/asphalt green compact, and mechanically fusing the graphite/nano silicon/asphalt green compact for 30min in a mechanical fusion machine at a linear speed of 40m/s to obtain graphite/nano silicon/asphalt composite particles; calcining for 4 hours at 900 ℃ under the protection of inert atmosphere; and scattering and screening to obtain the silicon-carbon composite negative electrode material with the silicon content of 33%.
Example 3:
adding 2kg of micron silicon powder with the median particle size of 3 mu m and the silicon content of more than 99 percent into 18kg of ethanol solvent, performing ultrasonic dispersion for 30min, and pouring into a cavity of an ultrafine ball mill. Zirconia balls with the diameter of 0.3mm are used as ball milling media, the ball-material ratio (mass ratio) is 10:1, and ball milling is carried out for 10 hours at the rotating speed of 1800rpm, so as to obtain the nano silicon dispersion liquid. Adding 3.4kg of flake graphite into the nano-silicon dispersion liquid, and performing ball milling dispersion for 1 hour at the rotating speed of 1000rpm to obtain uniform mixed slurry. And (4) carrying out spray drying on the mixed slurry to obtain granular composite powder.
Taking 2kg of the powdery intermediate product obtained by spray drying and 1kg of modified coal pitch, and carrying out hot kneading for 2h at the temperature of 120-140 ℃; hot rolling the kneaded product at the temperature of 120-140 ℃ to obtain rubber packing with the thickness of about 2mm, and crushing the rubber packing into a powder material after cooling; then putting the powder material into a rubber sheath, and carrying out isostatic pressing for 10 minutes under the pressure of 200MPa in an isostatic press to obtain a graphite/nano silicon/asphalt blocky green compact; then crushing and sieving the formed graphite/nano silicon/asphalt green compact, and mechanically fusing the graphite/nano silicon/asphalt green compact for 30min in a mechanical fusion machine at the linear speed of 35m/s to obtain graphite/nano silicon/asphalt composite particles; calcining for 4 hours at 900 ℃ under the protection of inert atmosphere; and scattering and screening to obtain the silicon-carbon composite negative electrode material with the silicon content of 33%.
Example 4:
adding 2kg of micron silicon powder with the median particle size of 3 mu m and the silicon content of more than 99 percent into 18kg of ethanol solvent, performing ultrasonic dispersion for 30min, and pouring into a cavity of an ultrafine ball mill. Zirconia balls with the diameter of 0.3mm are used as ball milling media, the ball-material ratio (mass ratio) is 10:1, and ball milling is carried out for 10 hours at the rotating speed of 1800rpm, so as to obtain the nano silicon dispersion liquid. Adding 3.4kg of flake graphite into the nano-silicon dispersion liquid, and performing ball milling dispersion for 1 hour at the rotating speed of 1000rpm to obtain uniform mixed slurry. And (4) carrying out spray drying on the mixed slurry to obtain granular composite powder.
Taking 2kg of the powdery intermediate product obtained by spray drying and 1kg of medium-temperature coal pitch, and carrying out hot kneading for 2h at the temperature of 120-140 ℃; hot rolling the kneaded product at the temperature of 120-140 ℃ to obtain rubber packing with the thickness of about 2mm, and crushing the rubber packing into a powder material after cooling; then putting the powder material into a rubber sheath, and carrying out isostatic pressing for 10 minutes under the pressure of 200MPa in an isostatic press to obtain a graphite/nano silicon/asphalt blocky green compact; then crushing and sieving the formed graphite/nano silicon/asphalt green compact, and mechanically fusing the graphite/nano silicon/asphalt green compact for 30min in a mechanical fusion machine at a linear speed of 45m/s to obtain graphite/nano silicon/asphalt composite particles; calcining for 4 hours at 900 ℃ under the protection of inert atmosphere; and scattering and screening to obtain the silicon-carbon composite negative electrode material with the silicon content of 33%.
Example 5:
adding 2kg of micron silicon powder with the median particle size of 3 mu m and the silicon content of more than 99 percent into 18kg of ethanol solvent, performing ultrasonic dispersion for 30min, and pouring into a cavity of an ultrafine ball mill. Zirconia balls with the diameter of 0.3mm are used as ball milling media, the ball-material ratio (mass ratio) is 10:1, and ball milling is carried out for 10 hours at the rotating speed of 1800rpm, so as to obtain the nano silicon dispersion liquid. Adding 3.4kg of flake graphite into the nano-silicon dispersion liquid, and performing ball milling dispersion for 1 hour at the rotating speed of 1000rpm to obtain uniform mixed slurry. And (4) carrying out spray drying on the mixed slurry to obtain granular composite powder.
Taking 2kg of the powdery intermediate product obtained by spray drying and 0.88kg of high-temperature coal tar pitch, and carrying out hot kneading for 2h at the temperature of 220-; hot rolling the kneaded product at the temperature of 220-250 ℃ to obtain rubber packing with the thickness of about 2mm, and crushing the rubber packing into a powder material after cooling; then putting the powder material into a rubber sheath, and carrying out isostatic pressing for 10 minutes under the pressure of 200MPa in an isostatic press to obtain a graphite/nano silicon/asphalt blocky green compact; then crushing and sieving the formed graphite/nano silicon/asphalt green compact, and mechanically fusing the graphite/nano silicon/asphalt green compact for 20min in a mechanical fusion machine at a linear speed of 45m/s to obtain graphite/nano silicon/asphalt composite particles; calcining for 4 hours at 900 ℃ under the protection of inert atmosphere; and scattering and screening to obtain the silicon-carbon composite negative electrode material with the silicon content of 33%.
Example 6:
adding 2kg of micron silicon powder with the median particle size of 3 mu m and the silicon content of more than 99 percent into 18kg of ethanol solvent, performing ultrasonic dispersion for 30min, and pouring into a cavity of an ultrafine ball mill. Zirconia balls with the diameter of 0.3mm are used as ball milling media, the ball-material ratio (mass ratio) is 10:1, and ball milling is carried out for 10 hours at the rotating speed of 1800rpm, so as to obtain the nano silicon dispersion liquid. 5.5kg of flake graphite is added into the nano-silicon dispersion liquid, and uniform mixed slurry is obtained after ball milling dispersion for 1 hour at the rotating speed of 1000 rpm. And (4) carrying out spray drying on the mixed slurry to obtain granular composite powder.
Taking 2kg of the powdery intermediate product obtained by spray drying and 1kg of modified coal pitch, and carrying out hot kneading for 2h at the temperature of 160-180 ℃; hot rolling the kneaded product at 160-180 ℃ to obtain a rubber package with the thickness of about 2mm, and crushing the rubber package into a powder material after cooling; then putting the powder material into a rubber sheath, and carrying out isostatic pressing for 10 minutes under the pressure of 200MPa in an isostatic press to obtain a graphite/nano silicon/asphalt blocky green compact; then crushing and sieving the formed graphite/nano silicon/asphalt green compact, and mechanically fusing the graphite/nano silicon/asphalt green compact for 20min in a mechanical fusion machine at a linear speed of 45m/s to obtain graphite/nano silicon/asphalt composite particles; calcining for 4 hours at 900 ℃ under the protection of inert atmosphere; and scattering and screening to obtain the silicon-carbon composite anode material with the silicon content of 22%.
Comparative example 1:
adding 2kg of micron silicon powder with the median particle size of 3 mu m and the silicon content of more than 99 percent into 18kg of ethanol solvent, performing ultrasonic dispersion for 30min, and pouring into a cavity of an ultrafine ball mill. Zirconia balls with the diameter of 0.3mm are used as ball milling media, the ball-material ratio (mass ratio) is 10:1, and ball milling is carried out for 10 hours at the rotating speed of 1800rpm, so as to obtain the nano silicon dispersion liquid. Adding 3.4kg of flake graphite into the nano-silicon dispersion liquid, and performing ball milling dispersion for 1 hour at the rotating speed of 1000rpm to obtain uniform mixed slurry. And (4) carrying out spray drying on the mixed slurry to obtain granular composite powder.
Taking 2kg of the powdery intermediate product obtained by spray drying and 1kg of modified coal pitch, and carrying out hot kneading for 2h at the temperature of 160-180 ℃; hot rolling the kneaded product at 160-180 ℃ to obtain a rubber package with the thickness of about 2mm, and crushing the rubber package into a powder material after cooling; then putting the powder material into a rubber sheath, and carrying out isostatic pressing for 10 minutes under the pressure of 200MPa in an isostatic press to obtain a graphite/nano silicon/asphalt blocky green compact; then crushing and sieving the formed graphite/nano silicon/asphalt green compact, and calcining for 4 hours at 900 ℃ under the protection of inert atmosphere; and scattering and screening to obtain the silicon-carbon composite negative electrode material with the silicon content of 33%.
Comparative example 2:
adding 2kg of micron silicon powder with the median particle size of 3 mu m and the silicon content of more than 99 percent into 18kg of ethanol solvent, performing ultrasonic dispersion for 30min, and pouring into a cavity of an ultrafine ball mill. Zirconia balls with the diameter of 0.3mm are used as ball milling media, the ball-material ratio (mass ratio) is 10:1, and ball milling is carried out for 10 hours at the rotating speed of 1800rpm, so as to obtain the nano silicon dispersion liquid. Adding 3.4kg of flake graphite into the nano-silicon dispersion liquid, and performing ball milling dispersion for 1 hour at the rotating speed of 1000rpm to obtain uniform mixed slurry. And (4) carrying out spray drying on the mixed slurry to obtain granular composite powder.
Taking 2kg of the powdery intermediate product obtained by spray drying, 780g of PVP caking agent and a proper amount of hydrosolvent, and kneading for 2h at normal temperature; drying and crushing the kneaded product; then, isostatic pressing is carried out on the powder material for 10 minutes under the pressure of 200MPa, and a block-shaped green body is obtained; then crushing and sieving the green body, and mechanically fusing the green body in a mechanical fusion machine for 20min at a linear speed of 45m/s to obtain composite particles; calcining for 4 hours at 900 ℃ under the protection of inert atmosphere; and scattering and screening to obtain the silicon-carbon composite negative electrode material with the silicon content of 33%.
Comparative example 3:
adding 2kg of micron silicon powder with the median particle size of 3 mu m and the silicon content of more than 99 percent into 18kg of ethanol solvent, performing ultrasonic dispersion for 30min, and pouring into a cavity of an ultrafine ball mill. Zirconia balls with the diameter of 0.3mm are used as ball milling media, the ball-material ratio (mass ratio) is 10:1, and ball milling is carried out for 10 hours at the rotating speed of 1800rpm, so as to obtain the nano silicon dispersion liquid. Adding 3.4kg of flake graphite into the nano-silicon dispersion liquid, and performing ball milling dispersion for 1 hour at the rotating speed of 1000rpm to obtain uniform mixed slurry. And (4) carrying out spray drying on the mixed slurry to obtain granular composite powder.
Taking 2kg of the powdery intermediate product obtained by spray drying, 1kg of phenolic resin and a proper amount of ethanol solvent, and kneading for 2h at normal temperature; drying and crushing the kneaded product; then, the powder material is subjected to isostatic pressing for 10 minutes under the pressure of 200MPa to obtain a graphite/nano silicon/phenolic resin blocky green compact; then crushing and sieving the graphite/asphalt/phenolic resin green bodies, and mechanically fusing for 20min in a mechanical fusing machine at a linear speed of 45m/s to obtain composite particles; calcining for 4 hours at 900 ℃ under the protection of inert atmosphere; and scattering and screening to obtain the silicon-carbon composite negative electrode material with the silicon content of 33%.
Examples 1 to 6 and comparative examples 1 to 3 were prepared in the following manner to prepare electrodes and to test electrochemical properties of the materials, and the test results are shown in table 1.
Dissolving a silicon-carbon composite negative electrode material, a conductive agent and a binder in a mass ratio of 86:6:8The solid content in the solvent was 30%. Wherein the binder adopts sodium carboxymethylcellulose (CMC,2 wt% CMC aqueous solution) styrene butadiene rubber (SBR,50 wt% SBR aqueous solution) composite water system binder with the mass ratio of 1: 1. Then 0.8 wt% of oxalic acid is added as an acidic substance for etching the copper foil, and uniform slurry is obtained after full stirring. Coating on 10 μm copper foil, drying at room temperature for 4 hr, punching into pole piece with 14 mm diameter punch at 100kg/cm-2Tabletting under pressure, and drying in a vacuum oven at 120 deg.C for 8 hr.
Transferring the pole piece into a glove box, and adopting a metal lithium piece as a negative pole, a Celgard2400 diaphragm and L iPF of 1 mol/L6Button cell assembled by/EC + DMC + EMC + 2% VC (v/v/v is 1:1:1) electrolyte and CR2016 battery case constant current charge and discharge test is carried out on the Wuhanjinuo L and CT2001A battery test system, charge and discharge are carried out circularly under 0.2C multiplying power, and charge and discharge cut-off voltage is relative to L i/L i+Is 0.005-2V.
Table 1 performance test results of high tap density silicon carbon negative electrode materials.
Figure BDA0001468825840000121
Figure BDA0001468825840000131
From the table, it can be seen that the tap density of the silicon-carbon composite negative electrode material obtained by the preparation method of the silicon-carbon negative electrode material comprising the mechanical fusion process step is improved, the specific surface area is reduced, and the first-cycle coulombic efficiency and the cycle stability of the material are greatly improved.
It should be understood that the above examples are only for clarity of illustration and are not intended to limit the embodiments. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. And obvious variations or modifications therefrom are within the scope of the invention.

Claims (9)

1. A preparation method of a high-performance silicon-carbon negative electrode material comprises the following steps:
(1) dispersing silicon in a solvent, performing liquid phase ball milling to obtain a nano silicon dispersion liquid, adding graphite, and performing liquid phase ball milling to realize uniform mixing of nano silicon and graphite; the mass ratio of the used raw material silicon to the solvent is 1: 5-15; the mass ratio of the graphite to the used raw material silicon in the step (1) is 1-3: 1;
(2) granulating the slurry obtained by mixing in the step (1) to realize graphite/nano silicon composite granulation;
(3) performing composite granulation on the product obtained in the step (2) and asphalt by adopting a kneading-pressing-crushing method, and performing mechanical fusion treatment to realize sphericization and uniform coating of the graphite/nano silicon/asphalt composite particles in one step; the mass ratio of the product obtained in the step (2) to the asphalt is 1-4: 1; the linear velocity during mechanical fusion is 10-50m/s, and the time for mechanical fusion is 3-60 min;
(4) and carbonizing, scattering and screening to obtain the high-performance silicon-carbon composite negative electrode material.
2. The method according to claim 1, wherein the silicon content of the raw material silicon used in step (1) is not less than 99%;
the raw material silicon is micron silicon powder;
the solvent is the combination of 1 or more than 2 of ethanol, methanol, isopropanol, n-butanol, acetone and toluene;
the mass ratio of the used raw material silicon to the solvent is 1: 9.
3. The production method according to claim 1 or 2, wherein the ball milling media in step (1) are zirconia balls;
the ball-milling ball material mass ratio is 5-15:1 when preparing the nano silicon dispersion liquid;
the rotation speed of ball milling is 1500-2000rpm, and the ball milling time is more than 5 hours when the nano silicon dispersion liquid is prepared.
4. The preparation method according to claim 1 or 2, characterized in that the rotation speed of ball milling after adding graphite is 500-1500rpm, and the time of ball milling is more than 0.5 hour;
adding graphite and then performing ball milling, wherein the ball-to-material ratio is 3-15: 1;
and (3) adopting a spray drying method for granulation in the step (2).
5. The preparation method according to claim 1, wherein the graphite/nano silicon/asphalt composite granulation process in the step (3) comprises the following steps: hot mixing and kneading the product obtained in the step (2) and asphalt, then hot rolling, cooling and crushing into a powder material; then, isostatic pressing is carried out on the powder material to obtain a graphite/nano silicon/asphalt block green compact; the green body is then crushed and sieved.
6. The production method according to claim 5, wherein the asphalt is coal asphalt or petroleum asphalt having a softening temperature of 60 ℃ or higher;
the mass ratio of the product obtained in the step (2) to the asphalt is 2: 1.
7. The method according to claim 5, wherein the temperature of the hot kneading is 100 ℃ and 300 ℃ and the time is 1 hour or more;
the temperature of hot rolling is 100-300 ℃;
the pressure during isostatic pressing is 150-300MPa, and the time for isostatic pressing is more than 5 min.
8. The method according to any one of claims 5 to 7, wherein the time for mechanofusion is 15 to 30 min.
9. The preparation method according to claim 1, wherein the carbonization in step (4) is performed under the protection of inert atmosphere, the carbonization temperature is 800-1000 ℃, and the carbonization time is more than 2 h.
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CN112290006A (en) * 2020-11-23 2021-01-29 山东硅纳新材料科技有限公司 Simple and efficient preparation method of silicon-carbon anode material
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US20230080961A1 (en) * 2021-09-08 2023-03-16 Koppers Delaware, Inc. Dispersion of Coal Tar Pitch for Coating Graphitic Materials and Use in Li-Ion Battery Electrode Production
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CN115036481A (en) * 2022-06-21 2022-09-09 焦作熔创石墨科技有限公司 Shaping method and system of carbon negative electrode material

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102569726A (en) * 2010-12-30 2012-07-11 中国电子科技集团公司第十八研究所 Method for preparing lithium ion battery anode material coated with metal ions
CN102891297B (en) * 2012-11-10 2015-05-13 江西正拓新能源科技股份有限公司 Silicon-carbon composite material for lithium ion battery and preparation method thereof
CN106531980A (en) * 2015-11-17 2017-03-22 宁波杉杉新材料科技有限公司 Negative electrode material for lithium-ion battery and preparation method and application of negative electrode material
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