CN111653745A - Silicon-carbon negative electrode precursor material, silicon-carbon negative electrode material and preparation method thereof - Google Patents
Silicon-carbon negative electrode precursor material, silicon-carbon negative electrode material and preparation method thereof Download PDFInfo
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Abstract
The invention provides a silicon-carbon negative electrode precursor material, a silicon-carbon negative electrode material and a preparation method thereof. The preparation method comprises the following steps: uniformly mixing the nano silicon powder, the graphite and the polymer to obtain a nano silica ink composite material; pressurizing the nano silicon graphite composite material to obtain a compact nano silicon graphite composite block material; and carbonizing the nano silica ink composite block in an inert atmosphere to obtain the silicon-carbon negative electrode precursor material. The preparation method ensures the bonding strength and the dispersion uniformity of silicon/graphite/amorphous carbon, greatly relieves the volume expansion effect of silicon in the charging and discharging processes, the prepared silicon-carbon cathode precursor material has the characteristics of high compaction density and uniform distribution of silicon and carbon, and the specific capacity, the first charging and discharging efficiency and the cycle performance of the prepared silicon-carbon cathode material are greatly improved.
Description
Technical Field
The invention belongs to the technical field of lithium ion batteries, and particularly relates to a silicon-carbon negative electrode precursor material, a silicon-carbon negative electrode material and a preparation method thereof.
Background
The lithium ion battery has the advantages of high energy density, high working voltage, stable discharge voltage, long cycle life, environmental protection and the like, is widely applied to portable electronic equipment, and has great influence on the electromotion of vehicles. The rapid development of electric vehicles also puts higher demands on the energy density, the cycle performance, the safety performance, the service life and the like of lithium ion batteries. The cathode material is an important component of the battery, and together with the anode material, the cathode material determines the key performances of the lithium ion battery, such as cycle life, capacity, safety and the like, and becomes a key point of research in various countries.
Silicon has attracted great attention in recent years as the most promising new-generation anode material, and the theoretical capacity of the silicon can reach 4200mAh/g (Li)22Si5) About ten times of carbonaceous materials, abundant reserves and lower lithium intercalation potential (Si average lithium removal potential 0.4V vs. Li/Li)+). However, silicon has a problem of low electronic conductivity, and silicon has a great volume change during alloying and dealloying with lithium ((>300%), resulting in easy breakage of silicon particles, structural collapse, and detachment of active materials from the current collector, thereby seriously affecting the cycle performance of the battery(ii) a And it is also difficult to form a stable SEI layer. The nano silicon and the carbonaceous material are compounded, so that the conductivity of the silicon-carbon cathode material can be improved, and the carbonaceous material can also be used as a buffer matrix to provide a certain buffer effect for the volume change of the silicon. However, the nano silicon has a large specific surface area and is easy to agglomerate, and the silicon in the obtained silicon-carbon composite material is often unevenly distributed, so that the improvement of the electrochemical performance of the negative electrode material is limited.
Disclosure of Invention
The invention aims to solve the technical problem of overcoming the defects and shortcomings in the background technology and provides a silicon-carbon anode precursor material, a silicon-carbon anode material and a preparation method thereof.
In order to solve the technical problems, the technical scheme provided by the invention is as follows:
a preparation method of a silicon-carbon negative electrode material comprises the following steps:
(1) uniformly mixing the nano silicon powder, the graphite and the polymer to obtain a nano silica ink composite material;
(2) pressurizing the nano silicon graphite composite material obtained in the step (1) to obtain a compact nano silicon graphite composite block material;
(3) and (3) carbonizing the nano silicon graphite composite block material obtained in the step (2) in an inert atmosphere to obtain the silicon-carbon negative electrode precursor material.
In the preparation method, the pressure of the pressure treatment is preferably 10-500Mpa, and the time is preferably 5-240 min. The pressure treatment is used for dispersing the agglomerated particles, so that the compaction density of the composite material is improved, the battery capacity is improved, and the rebound of the pole piece is reduced. In order to ensure the dispersion uniformity and the compacted density of the composite material, the parameters of the pressing treatment need to be controlled within the scope of the present invention.
Preferably, in the step (2), the temperature is raised to 30-300 ℃, the temperature is kept for 0.5-1.5h, and then the pressure treatment is carried out, wherein the temperature of the pressure treatment is 30-300 ℃, the pressure is 10-500Mpa, and the time is 5-240 min. The polymer is heated while being pressurized, so that the polymer is in a flowing state and is extruded into a gap between silicon and graphite under the action of pressure, the nano silicon is further uniformly dispersed in the carbon material, and the compaction density of the composite material is improved.
In the preparation method, preferably, the particle size of the nano silicon powder is 30-500nm, and the specific surface area of the graphite is 5-50m2The particle size D50 is 3-30 mu m, and the mass ratio of the nano silicon powder to the graphite is 1: 0.5-10.
In the above preparation method, preferably, the polymer is at least one of phenolic resin, epoxy resin, asphalt, fatty acid, polyethylene diamine, polypyrrole, polyaniline, polypropylene and polyvinylpyrrolidone, and the mass of the polymer is 0.5 wt% to 50 wt% of the total mass of the nano silicon powder, graphite and the polymer. In order to improve the dispersion uniformity of the raw materials, the polymer is dissolved in an organic solvent and then added, wherein the organic solvent is at least one of ethanol, methanol, polyethylene glycol, polypropylene alcohol, isopropanol, heavy oil, N-methyl pyrrolidone, tetrahydrofuran and acetone.
Preferably, in the step (1), in order to uniformly mix the silicon, the graphite and the polymer, the mixing process specifically includes adding the nano silicon powder into the organic solvent for sanding to obtain uniform and stable silicon slurry, then adding the graphite into the silicon slurry in a manner of edging and charging while continuing sanding to uniformly mix to obtain mixed slurry; carrying out spray granulation on the mixed slurry to obtain mixed granules with the particle size D50 of 5-50 mu m, adding the mixed granules into a polymer, uniformly mixing, and removing a solvent to obtain the nano silicon graphite composite material; the organic solvent is at least one of methanol, ethanol, glycol, propanol, isopropanol, butanol, pentanol, tetrahydrofuran, acetone and N-methylpyrrolidone.
In the preparation method, preferably, the carbonization treatment comprises a primary carbonization treatment at the temperature of 500-900 ℃ for 1-10 h.
In the above preparation method, preferably, the carbonization treatment includes two carbonization treatments, and the specific operation steps include: carrying out primary carbonization treatment on the nano silicon graphite composite block material in an inert atmosphere to obtain a primarily carbonized nano silicon graphite composite block material, crushing the block material, mixing the crushed block material with a carbon-containing material, and carrying out secondary carbonization treatment to obtain a silicon-carbon negative electrode material; wherein the temperature of the first carbonization treatment is 500-800 ℃, and the time is 1-10 h; the temperature of the second carbonization treatment is 800-; the carbonaceous material is pitch.
The present invention also provides, as a general inventive concept, a silicon carbon anode precursor material prepared according to the above-described preparation method.
As a general inventive concept, the invention also provides a silicon-carbon negative electrode material, which is prepared by mixing the silicon-carbon negative electrode precursor material and graphite, wherein the mass of the graphite is 70-90 wt% of that of the silicon-carbon negative electrode material.
Compared with the prior art, the invention has the advantages that:
according to the preparation method of the silicon-carbon cathode precursor material, silicon, graphite and a polymer are mixed in advance to form a uniform mixture, the agglomerated part is scattered in a pressurization treatment mode to be uniformly redistributed, and then the carbon formed by carbonizing the polymer of nano silicon is adhered to the surface of the crushed graphite through subsequent carbonization treatment, so that the silicon, the graphite and the carbon are in close contact, the adhesion strength and the dispersion uniformity of the silicon/graphite/amorphous carbon are ensured, and the volume expansion effect of the silicon in the charging and discharging process is greatly relieved; after the secondary coating carbon layer, the side reaction of the cathode material and the electrolyte can be further reduced, and the stability of the material is improved.
The preparation method disclosed by the invention is short in process flow, simple to operate, low in process cost, high in production efficiency, environment-friendly and suitable for large-scale production.
The silicon-carbon anode precursor material prepared by the invention has the characteristics of high compaction density and uniform silicon-carbon distribution, and the specific capacity, the first charge-discharge efficiency and the cycle performance of the prepared silicon-carbon anode material are greatly improved.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.
Fig. 1 is an SEM photograph of a silicon carbon negative electrode precursor material prepared in example 1 of the present invention;
fig. 2 is a first charge-discharge curve of a silicon-carbon anode prepared in example 1 of the present invention;
fig. 3 is a discharge specific capacity-cycle curve of a silicon carbon negative electrode prepared in example 1 of the present invention.
Detailed Description
In order to facilitate an understanding of the invention, the invention will be described more fully and in detail below with reference to the accompanying drawings and preferred embodiments, but the scope of the invention is not limited to the specific embodiments below.
Unless otherwise defined, all terms of art used hereinafter have the same meaning as commonly understood by one of ordinary skill in the art. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of the present invention.
Unless otherwise specifically stated, various raw materials, reagents, instruments, equipment and the like used in the present invention are commercially available or can be prepared by existing methods.
Example 1:
the invention relates to a preparation method of a silicon-carbon negative electrode precursor material, which comprises the following steps:
(1) adding 2kg of nano silicon powder with the particle size of 150nm into organic solvent ethanol, sanding for 8 hours at the rotating speed of 800rpm to obtain uniform and stable silicon slurry, and then adding 3kg of spherical graphite with the specific surface area of 15m2The grain diameter D50 is 10 mu m, and the mixture is continuously sanded for 1h at the rotating speed of 600rpm to obtain uniformly mixed slurry; carrying out spray granulation on the mixed slurry to obtain mixed granules with D50 of 25 mu m; adding the mixed granules into ethanol-polyvinylpyrrolidone solution (containing 5kg polyvinylpyrrolidone and 10L ethanol), and stirring and dispersing in double planetary disperser50min, uniformly mixing, placing the mixture in a vacuum drying oven, drying for 2h at 50 ℃, and evaporating ethanol to dryness to obtain the nano silicon graphite composite material;
(2) placing the nano silicon graphite composite material obtained in the step (1) in a mould pressing mould, setting the heating temperature to be 220 ℃, preserving the heat for 1h, pressurizing the mould to 250Mpa by using a hydraulic press, keeping the temperature and the pressure for 1.5h, and taking out a pressed blank by using a thimble after natural cooling to obtain a compact nano silicon graphite composite block material;
(3) placing the nano silicon graphite composite block material obtained in the step (2) in a box furnace under an inert atmosphere for primary carbonization treatment, wherein the carbonization temperature is 700 ℃, and the heat preservation time is 3 hours, so as to obtain a primarily carbonized nano silicon graphite composite block material; crushing the primarily carbonized nano silicon graphite composite block into powder with D50 of 15 mu m, mixing the powder with high-temperature asphalt in a VCH machine at the rotating speed of 1000rpm for 20min, placing the uniformly mixed mixture in a box furnace, performing secondary carbonization in an inert atmosphere, wherein the carbonization temperature is 900 ℃, the heat preservation time is 3h, naturally cooling, discharging, and sieving with a 325-mesh sieve to obtain the silicon-carbon cathode precursor material. The compacted density of the silicon-carbon anode precursor is 1.8g/cm3The tap density is 0.97g/cm3. An SEM photograph of a cross section of the silicon-carbon negative electrode precursor material after argon ion polishing and cutting is shown in figure 1, and it can be known from the figure that nano silicon is uniformly dispersed among graphite sheet layers through pressurization treatment, and the nano silicon and the graphite sheet layers are tightly adhered together through pyrolytic carbon formed by a polymer, so that the expansion of silicon can be effectively inhibited.
The silicon-carbon negative electrode precursor material prepared in the embodiment is mixed with artificial graphite, and the mass of the artificial graphite is 87 wt% of the mass of the silicon-carbon negative electrode material, so that the silicon-carbon negative electrode material is obtained.
Through tests, the first charge-discharge curve of the silicon-carbon negative electrode material prepared in the embodiment is shown in fig. 2, and as can be seen from the graph, the first charge specific capacity of the silicon-carbon negative electrode material is 494mAh/g, and the first charge-discharge efficiency is 90.78%; as shown in fig. 3, the specific discharge capacity-cycle curve indicates that the capacity retention rate was 84.5% after 100 cycles.
Example 2:
the invention relates to a preparation method of a silicon-carbon negative electrode precursor material, which comprises the following steps:
(1) adding 2kg of nano silicon powder with the particle size of 150nm into organic solvent ethanol, sanding for 8 hours at the rotating speed of 800rpm to obtain uniform and stable silicon slurry, and then adding 3kg of spherical graphite with the specific surface area of 15m2The grain diameter D50 is 10 mu m, and the mixture is continuously sanded for 1h at the rotating speed of 600rpm to obtain uniformly mixed slurry; carrying out spray granulation on the mixed slurry to obtain mixed granules with D50 of 25 mu m; adding the mixed granules into an NMP-polyaniline solution (containing 5kg of polyaniline and 10LNMP), stirring and dispersing for 50min in a double-planet dispersing machine, uniformly mixing, placing the mixture into a vacuum drying oven, drying for 2h at 50 ℃, and evaporating ethanol to dryness to obtain a nano silicon graphite composite material;
(2) placing the nano silicon graphite composite material obtained in the step (1) in an isostatic pressing die, pressurizing to 400Mpa, and maintaining the pressure for 4min to obtain a compact nano silicon graphite composite block material;
(3) placing the nano silicon graphite composite block material obtained in the step (2) in a box furnace under an inert atmosphere for primary carbonization treatment, wherein the carbonization temperature is 700 ℃, and the heat preservation time is 3 hours, so as to obtain a primarily carbonized nano silicon graphite composite block material; crushing the primarily carbonized nano silicon graphite composite block into powder with D50 of 15 mu m, mixing the powder with high-temperature asphalt in a VCH machine at the rotating speed of 1000rpm for 20min, placing the uniformly mixed mixture in a box furnace, performing secondary carbonization in an inert atmosphere, wherein the carbonization temperature is 900 ℃, the heat preservation time is 3h, naturally cooling, discharging, and sieving with a 325-mesh sieve to obtain the silicon-carbon cathode precursor material. The compacted density of the silicon-carbon anode precursor is 1.8g/cm3Tap density of 0.95g/cm3。
The silicon-carbon negative electrode precursor material prepared in the embodiment is mixed with artificial graphite, and the mass of the artificial graphite is 87 wt% of the mass of the silicon-carbon negative electrode material, so that the silicon-carbon negative electrode material is obtained.
Through tests, the first charge-discharge specific capacity of the silicon-carbon negative electrode material prepared in the embodiment is 487mAh/g, the first charge-discharge efficiency is 91.56%, and the capacity retention rate is 86.5% after 100-week circulation.
Example 3:
the invention relates to a preparation method of a silicon-carbon negative electrode precursor material, which comprises the following steps:
(1) adding 2kg of nano silicon powder with the particle size of 100nm into isopropanol as an organic solvent, sanding for 8 hours at the rotating speed of 800rpm to obtain uniform and stable silicon slurry, and then adding 3kg of spherical graphite with the specific surface area of 10m2The grain diameter D50 is 15 mu m, and the mixture is continuously sanded for 1h at the rotating speed of 600rpm to obtain uniformly mixed slurry; spray granulating the mixed slurry to obtain mixed granules with D50 of 25 μm, adding the mixed granules and 450g of phenolic resin into a kneader, kneading for 60min at 150 ℃, taking out the uniformly mixed mixture after natural cooling, and crushing to 1-3mm to obtain the nano silicon graphite composite material;
(2) placing the nano silicon graphite composite material obtained in the step (1) in an isostatic pressing die, pressurizing to 400Mpa, and maintaining the pressure for 4min to obtain a compact nano silicon graphite composite block material;
(3) placing the nano silicon graphite composite block material obtained in the step (2) in a box furnace under an inert atmosphere for primary carbonization treatment, wherein the carbonization temperature is 700 ℃, and the heat preservation time is 3 hours, so as to obtain a primarily carbonized nano silicon graphite composite block material; crushing the primarily carbonized nano silicon graphite composite block into powder with D50 of 15 mu m, mixing the powder with high-temperature asphalt in a VCH machine at the rotating speed of 1000rpm for 20min, placing the uniformly mixed mixture in a box furnace, performing secondary carbonization in an inert atmosphere, wherein the carbonization temperature is 900 ℃, the heat preservation time is 3h, naturally cooling, discharging, and sieving with a 325-mesh sieve to obtain the silicon-carbon cathode precursor material. The compacted density of the silicon-carbon anode precursor is 1.8g/cm3The tap density is 0.98g/cm3。
The silicon-carbon negative electrode precursor material prepared in the embodiment is mixed with artificial graphite, and the mass of the artificial graphite is 87 wt% of the mass of the silicon-carbon negative electrode material, so that the silicon-carbon negative electrode material is obtained.
Through tests, the first charge-discharge specific capacity of the silicon-carbon negative electrode material prepared in the embodiment is 486.28mAh/g, the first charge-discharge efficiency is 90.89%, and the capacity retention rate is 82.3% after 100 cycles.
Example 4:
the invention relates to a preparation method of a silicon-carbon negative electrode precursor material, which comprises the following steps:
(1) adding 2kg of nano silicon powder with the particle size of 100nm into organic solvent ethanol, sanding for 8 hours at the rotating speed of 800rpm to obtain uniform and stable silicon slurry, and then adding 3kg of spherical graphite with the specific surface area of 10m2The grain diameter D50 is 15 mu m, and the mixture is continuously sanded for 1h at the rotating speed of 600rpm to obtain uniformly mixed slurry; carrying out spray granulation on the mixed slurry to obtain mixed granules with D50 of 25 mu m, adding the mixed granules into a heavy oil solution in which 500g of asphalt is dissolved, stirring for 2h by double planets, and carrying out vacuum drying to obtain powder;
(2) placing the powder obtained in the step (1) in a mould, pressurizing to 200Mpa, keeping the temperature at 200 ℃, and maintaining the pressure for 30min to obtain a compact nano silica ink composite block material;
(3) crushing the nano silica ink composite block into powder with D50 of 15 mu m, mixing the powder with high-temperature asphalt in a VCH machine at the rotating speed of 1000rpm for 20min, placing the uniformly mixed mixture in a box furnace, carbonizing the mixture in an inert atmosphere at the carbonizing temperature of 1000 ℃, keeping the temperature for 3h, naturally cooling the mixture, discharging the material, and sieving the material with a 325-mesh sieve to obtain the silicon-carbon cathode precursor material. The compacted density of the silicon-carbon anode precursor is 1.8g/cm3Tap density of 0.95g/cm3。
The silicon-carbon negative electrode precursor material prepared in the embodiment is mixed with artificial graphite, and the mass of the artificial graphite is 87 wt% of the mass of the silicon-carbon negative electrode material, so that the silicon-carbon negative electrode material is obtained.
Through tests, the first charge-discharge specific capacity of the silicon-carbon negative electrode material prepared in the embodiment is 478.65mAh/g, the first charge-discharge efficiency is 90.96%, and the capacity retention rate is 85.2% after 100 weeks of circulation.
Comparative example 1:
a preparation method of a silicon-carbon negative electrode precursor material comprises the following steps:
(1) adding 2kg of nano silicon powder with the particle size of 150nm into the organic solution, sanding for 8 hours at the rotating speed of 800rpm to obtain uniform and stable silicon slurry,then 3kg of spherical graphite with a specific surface area of 15m was added2The grain diameter D50 is 15 mu m, and the mixture is continuously sanded for 1h at the rotating speed of 600rpm to obtain uniformly mixed slurry; carrying out spray granulation on the mixed slurry to obtain mixed granules with D50 of 25 mu m; adding the mixed granules into an ethanol-resin solution, stirring and dispersing for 50min in a double-planet dispersing machine at a solid-liquid ratio of 1:1, uniformly mixing, placing the mixture into a vacuum drying oven, drying for 2h at 50 ℃, and evaporating ethanol to dryness to obtain a nano silicon graphite composite material;
(2) directly placing the nano silicon graphite composite material obtained in the step (1) in a box furnace to carry out primary carbonization treatment in an inert atmosphere without pressurization treatment, wherein the carbonization temperature is 700 ℃, and the heat preservation time is 3 hours, so as to obtain the nano silicon graphite composite material subjected to primary carbonization; crushing the primarily carbonized nano silicon graphite composite block into powder with D50 of 15 mu m, mixing the powder with high-temperature asphalt in a VCH machine at the rotating speed of 1000rpm for 20min, placing the uniformly mixed mixture in a box furnace, performing secondary carbonization in an inert atmosphere, wherein the carbonization temperature is 900 ℃, the heat preservation time is 3h, naturally cooling, discharging, and sieving with a 325-mesh sieve to obtain the silicon-carbon cathode precursor material. The compacted density of the silicon-carbon anode precursor is 1.6g/cm3The tap density is 0.85g/cm3。
And mixing the silicon-carbon negative electrode precursor material prepared by the comparative example with artificial graphite, wherein the mass of the artificial graphite is 87 wt% of that of the silicon-carbon negative electrode material, so as to obtain the silicon-carbon negative electrode material.
Through tests, the first charge-discharge specific capacity of the silicon-carbon negative electrode material prepared in the comparative example is 465mAh/g, the first charge-discharge efficiency is 88.76%, and the capacity retention rate is 78.6% after 100-week circulation.
Claims (10)
1. The preparation method of the silicon-carbon negative electrode material is characterized by comprising the following steps of:
(1) uniformly mixing the nano silicon powder, the graphite and the polymer to obtain a nano silica ink composite material;
(2) pressurizing the nano silicon graphite composite material obtained in the step (1) to obtain a compact nano silicon graphite composite block material;
(3) and (3) carbonizing the nano silicon graphite composite block material obtained in the step (2) in an inert atmosphere to obtain the silicon-carbon negative electrode precursor material.
2. The method according to claim 1, wherein the pressure is 10 to 500Mpa for 5 to 240 min.
3. The preparation method according to claim 1, wherein in the step (2), the temperature is raised to 30-300 ℃ and the temperature is kept for 0.5-1.5h, and then the pressure treatment is carried out, wherein the temperature of the pressure treatment is 30-300 ℃, the pressure is 10-500Mpa, and the time is 5-240 min.
4. The preparation method according to claim 1, 2 or 3, characterized in that the particle size of the nano silicon powder is 30-500nm, and the specific surface area of the graphite is 5-50m2The particle size D50 is 3-30 mu m, and the mass ratio of the nano silicon powder to the graphite is 1: 0.5-10.
5. The preparation method according to claim 1, 2 or 3, wherein the polymer is at least one of phenolic resin, epoxy resin, asphalt, fatty acid, polyethylene diamine, polypyrrole, polyaniline, polypropylene and polyvinylpyrrolidone, and the mass of the polymer is 0.5 wt% to 50 wt% of the total mass of the nano silicon powder, the graphite and the polymer.
6. The preparation method according to claim 1, 2 or 3, wherein in the step (1), the mixing process comprises adding the nano silicon powder into the organic solvent, sanding, adding graphite in a manner of edging and charging, and continuously sanding and uniformly mixing to obtain mixed slurry; and carrying out spray granulation on the mixed slurry to obtain mixed granules with the particle size D50 of 5-50 mu m, adding the mixed granules into the polymer, uniformly mixing, and removing the solvent to obtain the nano silica ink composite material.
7. The method as claimed in claim 1, 2 or 3, wherein the carbonization treatment comprises a primary carbonization treatment at a temperature of 500-900 ℃ for a period of 1-10 hours.
8. The preparation method according to claim 1, 2 or 3, characterized in that the carbonization treatment comprises two carbonization treatments, and the specific operation steps are as follows: carrying out primary carbonization treatment on the nano silicon graphite composite block material in an inert atmosphere to obtain a primarily carbonized nano silicon graphite composite block material, crushing the block material, mixing the crushed block material with a carbon-containing material, and carrying out secondary carbonization treatment to obtain a silicon-carbon negative electrode material; wherein the temperature of the first carbonization treatment is 500-800 ℃, and the time is 1-10 h; the temperature of the second carbonization treatment is 800-; the carbonaceous material is pitch.
9. A silicon-carbon negative electrode precursor material prepared according to the preparation method of any one of claims 1 to 8.
10. The silicon-carbon negative electrode material is characterized by being prepared by mixing the silicon-carbon negative electrode precursor material of claim 9 and graphite, wherein the mass of the graphite is 70-90 wt% of the mass of the silicon-carbon negative electrode material.
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| CN112125304A (en) * | 2020-09-25 | 2020-12-25 | 福建师范大学 | Metal oxide modified micro-nano silicon-graphite composite negative electrode material and preparation method thereof |
| CN112234179A (en) * | 2020-10-26 | 2021-01-15 | 郑州中科新兴产业技术研究院 | Preparation method of high-capacity silicon-based negative electrode material |
| 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 |
| CN113571686A (en) * | 2021-06-23 | 2021-10-29 | 长沙矿冶研究院有限责任公司 | Preparation method of core-shell carbon-silicon negative electrode material |
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| CN113745465B (en) * | 2021-08-31 | 2023-01-24 | 长沙矿冶研究院有限责任公司 | Preparation method of silicon-carbon composite material |
| CN113745465A (en) * | 2021-08-31 | 2021-12-03 | 长沙矿冶研究院有限责任公司 | Preparation method of silicon-carbon composite material |
| CN114275760A (en) * | 2021-12-22 | 2022-04-05 | 江西紫宸科技有限公司 | Silicon-carbon composite material and preparation method and application thereof |
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| CN115050933A (en) * | 2022-05-30 | 2022-09-13 | 孟垂舟 | Silicon-carbon composite material and preparation method and application thereof |
| CN115050933B (en) * | 2022-05-30 | 2023-12-15 | 孟垂舟 | Silicon-carbon composite material and preparation method and application thereof |
| CN115000368B (en) * | 2022-05-30 | 2023-12-15 | 孟垂舟 | Preparation method of high-tap-density silicon-carbon composite material, silicon-carbon composite material and application |
| CN115020667A (en) * | 2022-06-24 | 2022-09-06 | 广东海洋大学 | Silicon-carbon composite negative electrode material and preparation method and application thereof |
| CN115020667B (en) * | 2022-06-24 | 2024-02-27 | 广东海洋大学 | Silicon-carbon composite anode material and preparation method and application thereof |
| CN115312699A (en) * | 2022-08-09 | 2022-11-08 | 湖北钛时代新能源有限公司 | Carbon-silicon negative electrode active material and secondary battery |
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