CN114824224A - Silicon-based negative electrode material, preparation method thereof and lithium ion battery - Google Patents
Silicon-based negative electrode material, preparation method thereof and lithium ion battery Download PDFInfo
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Abstract
The invention relates to the technical field of lithium ion batteries, and provides a silicon-based negative electrode material and a preparation method thereof, and a lithium ion battery, wherein the outer layer of the silicon-based negative electrode material is provided with a carbon coating layer with a special structure, the structure of the carbon coating layer is from a soluble organic carbon source, the molecular structure of the soluble organic carbon source is rich in an aromatic carbon ring and an aliphatic carbon structure, and is attached with a connected oxygen-containing or nitrogen-containing group, the content of aromatic carbon is not less than 10 wt% of the total carbon content, the ratio of the content of aromatic carbon to the content of aliphatic carbon is greater than 1, and the mass of the carbon coating layer accounts for 0.01-30 wt% of the mass of the silicon-based negative electrode material. Compared with other types of carbon coating layers, the special carbon coating layer formed by the invention can effectively accommodate the volume expansion of the silicon-based material without damaging the carbon structure layer, and the formed carbon conductive network can ensure the electrochemical activity of the silicon-based material in the charging and discharging processes, thereby greatly improving the quality and performance of the lithium ion battery.
Description
Technical Field
The invention relates to the technical field of lithium ion batteries, in particular to a silicon-based negative electrode material, a preparation method of the silicon-based negative electrode material and a lithium ion battery.
Background
Graphite has a limited specific capacity (372mAh/g) as a negative electrode material of a lithium ion battery, and the development of the graphite as the negative electrode material is limited.
The silicon negative electrode material is the most promising negative electrode material of the lithium ion battery due to the high theoretical specific capacity (4200mAh/g) and the low lithium intercalation potential (about 0.4V). However, the poor cycling stability of silicon-based negative electrode materials seriously affects the commercialization process, mainly because the silicon is accompanied by volume expansion of about as high as 400% during lithium intercalation, and the volume change causes the silicon particles to lose contact with the electrode, resulting in low cycling efficiency and fast capacity loss, which hinders the application thereof in lithium ion batteries. The carbon material coating is carried out on silicon, and is one of the most effective methods for improving the conductivity of the silicon-based material and improving the coulombic efficiency.
Carbon-coated silicon-based materials are one common form of silicon-based composite materials. In the prior art, the composite material of silicon and carbon is mainly prepared by the following method: the carbon-coated silicon material is directly deposited by gas phase CVD, or the carbon-coated structure is formed by thermal treatment after the coating of the silicon-coated material is melted by asphalt, or the carbon-coated structure is formed by thermal treatment after the coating of the common soluble micromolecule organic matter, high polymer and graphene solution is directly carried out liquid phase coating. These several mainstream carbon coating methods have their significant disadvantages. The chemical vapor deposition method can be used for preparing a more uniform carbon-coated structure, but due to the limitations of production conditions and equipment, the problem of non-uniformity still exists, the technical cost is still very high, and the mechanical strength of the generated carbon layer structure is poor. Complete and compact coating of particles is difficult to achieve in asphalt melting coating industry, tar is generated in the process, and the particles are easy to agglomerate. And the carbon layer formed by coating the conventional soluble micromolecule or high molecular organic matter is thin, has poor compactness and quality and low mechanical strength, and is difficult to bear the volume change of the silicon material in the charging and discharging processes. The graphene-coated silicon-based negative electrode material prepared in the ex-situ mode is difficult to ensure that the graphene sheet layer can uniformly and completely cover the whole surface of the silicon-based material, so that a compact carbon layer structure with a small specific surface area is obtained, and meanwhile, the production cost of the graphene-coated silicon-based negative electrode material is high.
Disclosure of Invention
In order to solve the technical problems, the invention provides a silicon-based negative electrode material, a preparation method thereof and a lithium ion battery, wherein a formed special carbon coating layer can effectively accommodate the volume expansion of the silicon-based material without damaging a composite carbon structure layer, and a formed carbon conductive network can ensure the electrochemical activity of the silicon-based material in the charging and discharging processes, so that the quality and the performance of the lithium ion battery are greatly improved.
The technical scheme adopted by the invention is as follows:
the outer layer of the silicon-based negative electrode material is provided with a carbon coating layer with a special structure, the structure of the carbon coating layer is derived from a soluble organic carbon source, the molecular structure of the soluble organic carbon source is rich in aromatic carbon rings and aliphatic carbon structures and is attached with connected oxygen-containing or nitrogen-containing groups, the content of aromatic carbon is not less than 10 wt% of the total carbon content, the ratio of the content of aromatic carbon to the content of aliphatic carbon is greater than 1, and the mass of the carbon coating layer accounts for 0.01-30 wt% of the mass of the silicon-based negative electrode material.
The Raman spectrum of the carbon coating layer shows that the intensity of a D peak (about 1300cm-1 carbon characteristic peak) is less than that of a G peak (about 1580cm-1 carbon characteristic peak), and the area ratio of the D peak to the G peak is 0.1-0.99.
The soluble organic carbon source can be dissolved in a polar solvent, wherein the polar solvent is one or more of water, methanol, ethanol, isopropanol, n-butanol, glycerol, propylene glycol, acetone and chloroform.
The soluble organic carbon source is one or more of anthraquinone-2, 6-disulfonate, lignosulfonate, fulvic acid, ulmic acid, black humic acid, tannic acid, mandelic acid, caffeic acid, beta-phenylpropionic acid, methyl cinnamate and melatonin.
The carbon source components used by the carbon coating layer enable the carbon nanotubes to be uniformly dispersed in the polar solvent through the interaction force with the carbon nanotubes, and the carbon nanotubes are compounded with the carbon nanotubes to form the composite carbon coating layer; the carbon nano tubes are uniformly distributed in the bulk phase structure of the carbon coating layer and are in direct contact with the silicon-based core, and the carbon nano tubes account for 0.01-10 wt% of the silicon-based negative electrode material.
The carbon nano-tube is a multi-wall carbon tube, or a single-wall carbon tube, or a mixture of the multi-wall carbon tube and the single-wall carbon tube.
The grain size of the silicon-based inner core is 50 nm-100 mu m, and the thickness of the carbon coating layer is 1nm-1 mu m.
The silicon-based core is made of Si or SiOx, wherein X is 0.1-1.9.
A preparation method of a silicon-based negative electrode material comprises the following steps: s1, mixing the silicon-based inner core with the soluble organic carbon source in a polar solvent, and obtaining a uniform dispersion system under the condition that the pH value is 3-12; s2, volatilizing the solvent in the dispersion system, and completing the process of coating the silicon-based inner core by the soluble organic carbon source in a liquid phase to obtain a carbon-containing precursor; s3, carrying out heat treatment on the carbon-containing precursor under a protective atmosphere to obtain the silicon-based anode material, wherein the treatment temperature is 700-1200 ℃, the heating rate is 1-20 ℃/min, and the heat preservation time is 1-6 h.
Optionally, step S1 further includes: and adding carbon nano tubes into the dispersion system, and forming a stable dispersion system through the interaction of a soluble organic carbon source and the carbon nano tubes.
A lithium ion battery comprises the silicon-based negative electrode material.
The invention has the beneficial effects that:
the silicon-based negative electrode material provided by the embodiment of the invention can improve the conductivity, reduce the contact between the material and an electrolyte, and further reduce the occurrence of side reactions, and meanwhile, the special carbon layer structure can effectively control the expansion of silicon and the stability of a conductive network, and improve the stability of the silicon-based negative electrode material in the using process.
According to the preparation method of the silicon-based negative electrode material, the process of coating the high-quality carbon layer structure on the surface of the silicon-based negative electrode material in situ is realized by using the low-cost organic carbon source, the organic carbon source can also interact with the carbon nano tube to form the composite carbon coating layer, the coating stability and uniformity of the whole carbon structure improve the conductivity of the silicon-based negative electrode material and improve the coulombic efficiency and the circulation stability, the coating layer can prevent the silicon surface from directly contacting and reacting with electrolyte, and meanwhile, the carbon coating layer can effectively accommodate the volume expansion and shrinkage of the silicon-based material due to the special carbon structure without being damaged.
The preparation method of the silicon-based negative electrode material provided by the embodiment of the invention does not use toxic reagents, expensive catalysts, combustible gases or other severe conditions, and is a safe, environment-friendly, economic and effective synthesis method of the carbon-coated silicon negative electrode material.
Drawings
Fig. 1 is a schematic structural diagram of a silicon-based anode material according to an embodiment of the present invention;
fig. 2 is a flowchart of a method for preparing a silicon-based anode material according to an embodiment of the present invention;
fig. 3 is a scanning electron microscope picture of a silicon-based negative electrode material prepared by the method for preparing the silicon-based negative electrode material according to the embodiment of the invention;
fig. 4 is a comparison graph of battery cycle performance of silicon-based negative electrode materials prepared by the method for preparing the silicon-based negative electrode material in the two embodiments of the present invention and the prior art.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
As shown in fig. 1, the silicon-based negative electrode material of the embodiment of the invention has a carbon coating layer 2 with a special structure on the outer layer except for an inner silicon-based core 1, the structure of the carbon coating layer 2 is derived from a soluble organic carbon source, the molecular structure of the soluble organic carbon source is rich in an aromatic carbon ring and an aliphatic carbon structure, and is attached with a connected oxygen-containing or nitrogen-containing group, the content of aromatic carbon is not less than 10 wt% of the total carbon content, the ratio of the content of aromatic carbon to the content of aliphatic carbon is greater than 1, and the mass of the carbon coating layer accounts for 0.01-30 wt% of the mass of the silicon-based negative electrode material.
The carbon coating layer 2 has a Raman spectrum showing that the intensity of a D peak (a characteristic carbon peak around 1300 cm-1) is smaller than that of a G peak (a characteristic carbon peak around 1580 cm-1), and the area ratio of the D peak to the G peak is in the range of 0.1 to 0.99.
In one embodiment of the present invention, the soluble organic carbon source is soluble in a polar solvent, which may be one or more of water, methanol, ethanol, isopropanol, n-butanol, glycerol, propylene glycol, acetone, chloroform. The soluble organic carbon source can be one or more of anthraquinone-2, 6-disulfonate, lignosulfonate, fulvic acid, ulmic acid, fulvic acid, humic acid, tannic acid, mandelic acid, caffeic acid, beta-phenylpropionic acid, methyl cinnamate and melatonin.
In one embodiment of the present invention, the carbon source component used in the carbon coating layer 2 makes the carbon nanotubes uniformly dispersed in the polar solvent by the interaction force with the carbon nanotubes, and forms a composite carbon coating layer by combining with the carbon nanotubes; the carbon nano tubes are uniformly distributed in the bulk phase structure of the carbon coating layer and are in direct contact with the silicon-based core, and the carbon nano tubes account for 0.01-10 wt% of the silicon-based negative electrode material. The carbon nanotube may be multi-walled carbon nanotube, single-walled carbon nanotube, or a mixture of multi-walled carbon nanotube and single-walled carbon nanotube.
In one embodiment of the present invention, the particle size of the silicon-based core 1 may be 50nm to 100 μm, and the silicon-based core 1 may be Si or SiOx, where X is 0.1 to 1.9. The thickness of the carbon coating layer 2 may be 1nm to 1 μm.
According to the silicon-based negative electrode material disclosed by the embodiment of the invention, the conductivity can be improved, and the contact between the material and an electrolyte can be reduced, so that the occurrence of side reactions is reduced, meanwhile, the special carbon layer structure can effectively control the expansion of silicon and the stability of a conductive network, and the stability of the silicon-based negative electrode material in the using process is improved.
In order to obtain the silicon-based anode material of the embodiment, the invention further provides a preparation method of the silicon-based anode material.
As shown in fig. 2, the preparation method of the silicon-based anode material according to the embodiment of the present invention includes the following steps:
and S1, mixing the silicon-based inner core with a soluble organic carbon source in a polar solvent, and obtaining a uniform dispersion system under the condition that the pH value is 3-12.
Optionally, carbon nanotubes may be added to the dispersion system to form a stable dispersion system through the interaction of the organic carbon source and the carbon nanotubes.
And S2, volatilizing the solvent in the dispersion system, and completing the process of coating the silicon-based inner core by the soluble organic carbon source in a liquid phase to obtain the carbon-containing precursor.
S3, carrying out heat treatment on the carbon-containing precursor under a protective atmosphere to obtain the silicon-based anode material, wherein the treatment temperature is 700-1200 ℃, the heating rate is 1-20 ℃/min, and the heat preservation time is 1-6 h.
Wherein, the protective atmosphere can adopt inert gases such as nitrogen, argon, nitrogen hydrogen or argon hydrogen.
The following describes the preparation method of the silicon-based anode material of the present invention in detail with reference to 6 specific examples.
Example 1
(1) 25g of SiO0.1 raw powder are weighed out, 25ml of deionized water are added and stirred for 2 h.
(2) 2g of humic acid is weighed and added into the solution in the step (1), 10ml of ammonia water is dripped into the solution, and the solution is stirred for 2 hours. The pH value can be adjusted by adding ammonia water.
(3) And (3) drying the solution in the step (2) in water bath at the drying temperature of 80 ℃ for 2 h.
(4) Grinding is adopted to crush the sample in the step (3) to prepare a precursor, and the particle size D50 of the precursor is 10-50 mu m.
(5) And (3) carrying out high-temperature treatment on the precursor under the protection of argon at the temperature of 800 ℃, at the heating rate of 5 ℃/min, and carrying out heat preservation for 2h to obtain the SiOx @ G1 negative electrode material. The BET of the resulting SiOx @ G1 was 6.5m2/G, and the resistivity was 0.45. omega. cm.
The morphology of the silicon-based anode material obtained in example 1 is shown in fig. 3.
Example 2
(1) 25g of SiO0.1 raw powder is weighed, 25ml of deionized water is added, 0.1 wt% of carbon nanotube slurry is dripped, and stirring is carried out for 2 h.
(2) Weighing 2g of fulvic acid, adding the fulvic acid into the solution in the step (1), and stirring for 2 h.
(3) And (3) drying the solution in the step (2) in water bath at the drying temperature of 80 ℃ for 2 h.
(4) Grinding is adopted to crush the sample in the step (3) to prepare a precursor, and the particle size D50 of the precursor is 10-50 mu m.
(5) And (3) carrying out high-temperature treatment on the precursor under the protection of argon at the temperature of 800 ℃, at the heating rate of 5 ℃/min, and carrying out heat preservation for 2h to obtain the SiOx @ G2 negative electrode material. The obtained SiOx @ G2 had a BET of 2.5m2/G and a resistivity of 0.9. omega. cm.
Example 3
(1) 25g of SiO1.9 raw powder is weighed, 25ml of deionized water is added, 0.5 wt% of carbon nanotube slurry is dripped, and stirring is carried out for 2 h.
(2) 10ml of ammonia water was added dropwise to the solution of step (1), and the mixture was stirred for 2 hours.
(3) And (3) drying the solution in the step (2) in water bath at the drying temperature of 80 ℃ for 2 h.
(4) Grinding is adopted to crush the sample in the step (3) to prepare a precursor, and the particle size D50 of the precursor is 10-50 mu m.
(5) And (3) carrying out high-temperature treatment on the precursor under the protection of argon at the temperature of 800 ℃, at the heating rate of 5 ℃/min, and carrying out heat preservation for 2H to obtain the SiOx @ G3 negative electrode material. The obtained SiOx @ G3 had a BET of 2m2/G and a resistivity of 0.48. omega. cm.
Example 4
(1) 100g of SiO0.1 raw powder is weighed, 100ml of deionized water is added, 0.5 wt% of carbon nanotube slurry is dripped, and stirring is carried out for 2 h.
(2) 8g of humic acid is weighed and added into the solution in the step (1), 40ml of ammonia water is dripped into the solution, and the solution is stirred for 2 hours.
(3) And (3) carrying out spray granulation on the solution in the step (2) at the granulation temperature of 110 ℃.
(4) The particle size D50 of the precursor obtained by spray granulation is 30-100 μm.
(5) And (3) carrying out high-temperature treatment on the precursor under the protection of argon at the temperature of 800 ℃, at the heating rate of 5 ℃/min, and carrying out heat preservation for 2H to obtain the SiOx @ G4 negative electrode material. The BET of the resulting SiOx @ G4 was 5.5m2/G, and the resistivity was 0.45. omega. cm.
Example 5
(1) 100g of SiO raw powder is weighed, 100ml of deionized water is added, and stirring is carried out for 2 h.
(2) 8g of humic acid is weighed and added into the solution in the step (1), 40ml of ammonia water is dripped into the solution, and the solution is stirred for 2 hours.
(3) And (3) carrying out spray granulation on the solution in the step (2) at the granulation temperature of 110 ℃.
(4) The particle size D50 of the precursor obtained by spray granulation is 30-100 μm.
(5) And (3) carrying out high-temperature treatment on the precursor under the protection of argon at the temperature of 800 ℃, at the heating rate of 5 ℃/min, and carrying out heat preservation for 2H to obtain the SiOx @ G5 negative electrode material. The obtained SiOx @ G5 had a BET of 2.0m2/G and a resistivity of 0.45. omega. cm.
Example 6
(1) 100g of SiO1.9 raw powder is weighed, 100ml of deionized water is added, 0.5 wt% of carbon nano tube slurry is dripped, and the mixture is stirred for 2 hours.
(2) 8g of fulvic acid is weighed, added to the solution in step (1) and stirred for 2 h.
(3) And (3) carrying out spray granulation on the solution in the step (2) at the granulation temperature of 110 ℃.
(4) The particle size D50 of the precursor obtained by spray granulation is 30-100 μm.
(5) And (3) carrying out high-temperature treatment on the precursor under the protection of argon at the temperature of 800 ℃, at the heating rate of 5 ℃/min, and carrying out heat preservation for 2H to obtain the SiOx @ G6 negative electrode material. The obtained SiOx @ G6 had a BET of 1.5m2/G and a resistivity of 0.45. omega. cm.
To verify the effect of the silicon-based negative electrode material prepared by the method of the embodiment of the present invention applied to the battery, a certain preparation method in the prior art is used as a comparative example 1, the battery cycle performance of the silicon-based negative electrode material prepared by the method is compared with the battery cycle performance of the silicon-based negative electrode material prepared by the above-mentioned embodiment 1 and embodiment 2 of the present invention, and the comparison result is shown in fig. 4.
According to the preparation method of the silicon-based anode material, the process of coating the high-quality carbon layer structure on the surface of the silicon-based anode material in situ is realized by using the low-cost organic carbon source, the organic carbon source can also interact with the carbon nano tube to form the composite carbon coating layer, the coating stability and uniformity of the whole carbon structure improve the conductivity of the silicon-based anode material and improve the coulombic efficiency and the circulation stability, the coating layer can prevent the silicon surface from directly contacting and reacting with electrolyte, and meanwhile, the carbon coating layer can effectively contain the volume expansion and contraction of the silicon-based material due to the special carbon structure without being damaged. In addition, the preparation method of the silicon-based anode material disclosed by the embodiment of the invention does not use toxic reagents, expensive catalysts, combustible gases or other severe conditions, and is a safe, environment-friendly, economic and effective synthesis method of the carbon-coated silicon anode material.
Based on the silicon-based negative electrode material of the embodiment, the invention further provides a lithium ion battery.
The lithium ion battery of the embodiment of the invention comprises the silicon-based negative electrode material of any one of the embodiments of the invention.
The lithium ion battery provided by the embodiment of the invention has better quality and performance.
In the description of the present invention, "a plurality" means two or more unless specifically defined otherwise.
In the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, various embodiments or examples and features of different embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction.
Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention, and that variations, modifications, substitutions and alterations can be made to the above embodiments by those of ordinary skill in the art within the scope of the present invention.
Claims (10)
1. The silicon-based negative electrode material is characterized in that an outer layer is provided with a carbon coating layer with a special structure, the carbon coating layer structure is derived from a soluble organic carbon source, the molecular structure of the soluble organic carbon source is rich in an aromatic carbon ring and an aliphatic carbon structure, and is attached with a connected oxygen-containing or nitrogen-containing group, the content of aromatic carbon is not less than 10 wt% of the total carbon content, the ratio of the content of aromatic carbon to the content of aliphatic carbon is greater than 1, and the mass of the carbon coating layer accounts for 0.01-30 wt% of the mass of the silicon-based negative electrode material.
2. The silicon-based anode material according to claim 1, wherein a raman spectrum of the carbon coating layer shows that the intensity of a D peak (a carbon characteristic peak around 1300cm "1) is smaller than the intensity of a G peak (a carbon characteristic peak around 1580 cm" 1), and the area ratio of the D peak to the G peak is in a range of 0.1 to 0.99.
3. The silicon-based anode material of claim 2, wherein the soluble organic carbon source is soluble in a polar solvent, and the polar solvent is one or more of water, methanol, ethanol, isopropanol, n-butanol, glycerol, propylene glycol, acetone, and chloroform.
4. The silicon-based negative electrode material of claim 3, wherein the soluble organic carbon source is one or more of anthraquinone-2, 6-disulfonate, lignosulfonate, fulvic acid, ulmic acid, fulvic acid, humic acid, tannic acid, mandelic acid, caffeic acid, beta-phenylpropionic acid, methyl cinnamate and melatonin.
5. The silicon-based negative electrode material as claimed in claim 4, wherein the carbon source component used in the carbon coating layer enables the carbon nanotubes to be uniformly dispersed in the polar solvent through the interaction force with the carbon nanotubes, and the carbon nanotubes are compounded with the carbon nanotubes to form the composite carbon coating layer; the carbon nano tubes are uniformly distributed in the bulk phase structure of the carbon coating layer and are in direct contact with the silicon-based inner core, and the carbon nano tubes account for 0.01-10 wt% of the silicon-based negative electrode material.
6. The silicon-based anode material of claim 5, wherein the carbon nanotubes are multi-walled carbon tubes, single-walled carbon tubes, or a mixture of multi-walled carbon tubes and single-walled carbon tubes.
7. The silicon-based negative electrode material of claim 6, wherein the silicon-based core has a particle size of 50nm to 100 μm, and the carbon coating layer has a thickness of 1nm to 1 μm.
8. A method for preparing a silicon-based anode material according to any one of claims 1 to 7, comprising the steps of:
s1, mixing the silicon-based inner core with the soluble organic carbon source in a polar solvent, and obtaining a uniform dispersion system under the condition that the pH value is 3-12;
s2, volatilizing the solvent in the dispersion system, and completing the process of coating the silicon-based inner core by the soluble organic carbon source in a liquid phase to obtain a carbon-containing precursor;
s3, carrying out heat treatment on the carbon-containing precursor under a protective atmosphere to obtain the silicon-based negative electrode material, wherein the treatment temperature is 700-1200 ℃, the heating rate is 1-20 ℃/min, and the heat preservation time is 1-6 h.
9. The method of claim 8, wherein step S1 further comprises:
and adding carbon nano tubes into the dispersion system, and forming a stable dispersion system through the interaction of a soluble organic carbon source and the carbon nano tubes.
10. A lithium ion battery comprising the silicon-based negative electrode material of any one of claims 1 to 7.
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108493452A (en) * | 2018-03-13 | 2018-09-04 | 陕西科技大学 | It is a kind of to inhibit the aqueous binders of pole piece material expansion and lithium ion battery negative material and preparation method based on it |
| CN110229275A (en) * | 2019-06-19 | 2019-09-13 | 江苏塔菲尔新能源科技股份有限公司 | A kind of binder and preparation method thereof, and include its pole piece and lithium ion battery |
| US20200266481A1 (en) * | 2019-02-15 | 2020-08-20 | Murata Manufacturing Co., Ltd. | Negative electrode additive for a lithium ion secondary battery and a negative electrode slurry containing the same |
| CN112952059A (en) * | 2021-02-09 | 2021-06-11 | 昆山宝创新能源科技有限公司 | Silicon-based negative electrode material and preparation method and application thereof |
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Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108493452A (en) * | 2018-03-13 | 2018-09-04 | 陕西科技大学 | It is a kind of to inhibit the aqueous binders of pole piece material expansion and lithium ion battery negative material and preparation method based on it |
| US20200266481A1 (en) * | 2019-02-15 | 2020-08-20 | Murata Manufacturing Co., Ltd. | Negative electrode additive for a lithium ion secondary battery and a negative electrode slurry containing the same |
| CN110229275A (en) * | 2019-06-19 | 2019-09-13 | 江苏塔菲尔新能源科技股份有限公司 | A kind of binder and preparation method thereof, and include its pole piece and lithium ion battery |
| CN112952059A (en) * | 2021-02-09 | 2021-06-11 | 昆山宝创新能源科技有限公司 | Silicon-based negative electrode material and preparation method and application thereof |
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