TWI820144B - Manufacturing method of composite carbon silicon negative electrode base material and composite carbon silicon negative electrode base material made by the manufacturing method - Google Patents

Abstract

A method for manufacturing a composite carbon silicon negative electrode substrate and a composite carbon silicon negative electrode substrate formed by the manufacturing method. The composite carbon silicon negative electrode substrate includes a first-order carbon silicon ball, a plurality of graphene sheets, and a plurality of graphene sheets. A composite monomer of nanoscale silicon and silicon oxide and a plurality of first polymer materials; the first polymer material is used as an adhesive to connect the plurality of graphene sheets and the plurality of nanoscale silicon and oxide A composite monomer of silicon; wherein a plurality of buffer gaps are formed between the plurality of graphene sheets, the plurality of composite monomers of nanoscale silicon and silicon oxide, and the plurality of first polymer materials; a second polymer The material layer is coated on the outside of the first-stage carbon silicon ball; the second polymer material layer is sintered to carbonize the sugars to increase the structural capacity of the overall composite carbon silicon negative electrode matrix; and a plurality of nanometer The carbon tube tightly wraps the second polymer material layer; the carbon nanotube wraps the second polymer material layer, which has a tight binding effect so that the first-order carbon silicon ball inside is not easy to expand.

Description

Manufacturing method of composite carbon silicon negative electrode base material and composite made by the manufacturing method Composite carbon silicon negative electrode matrix

The present invention relates to battery negative electrode materials, in particular to a manufacturing method of a composite carbon silicon negative electrode base material and a composite carbon silicon negative electrode base body made by the manufacturing method.

Among the negative electrode materials of lithium batteries, graphite is traditionally used to insert lithium atoms. Because graphite has a limited capacity and cannot meet future market needs, the best way is to use silicon materials (pure silicon, silicon oxide) partially in combination with graphite. Because the electric capacity of silicon material is higher than that of graphite, the entire negative electrode can have a larger electric capacity to increase the storage capacity of the battery.

However, in traditional lithium-silicon batteries, lithium atoms are inserted into the crystal structure of the silicon material through electrochemical reactions. When chemical discharge is performed, most of the active lithium leaves the crystal structure, but there is still a part of the active lithium that will undergo partial side reactions due to the reaction rate and the electrochemically active substances in the electrolyte, resulting in the precipitation of lithium salts, and the precipitation will occur in the A layer of film, the SEI film, is formed around the silicon material. During charging, the silicon material accommodates lithium to form a lithium silicon crystal structure. This structure is much larger than the original silicon material structure, and the volume of the entire silicon material will expand; however, during discharge, the active lithium leaves the silicon crystal structure and leaves a cavity. The entire material will appear soft, and the structure may collapse under the electrochemical reaction. After repeated charging and discharging, the cavity will be distorted and fragmented over time, thus reducing the capacitance of the entire silicon material.

Therefore, this case hopes to propose a new manufacturing method of composite carbon silicon negative electrode substrate and a composite carbon silicon negative electrode substrate made by the manufacturing method, so as to solve the above-mentioned shortcomings of the previous technology.

Therefore, the purpose of the present invention is to solve the above-mentioned problems in the conventional technology. The present invention proposes a manufacturing method of a composite carbon silicon negative electrode base material and a composite carbon silicon negative electrode base material made by the manufacturing method. A graphene sheet, a plurality of composite monomers of nanoscale silicon and silicon oxide and a plurality of first polymer materials are mixed to form a first-order carbon silicon ball, and the first polymer material is used as an adhesive to connect the Graphene sheets and composite monomers of nanoscale silicon and silicon oxide. The graphene sheet is a tough and elastic structure that will not easily deform, so it can limit the expansion of the composite monomer of nanoscale silicon and silicon oxide, thus making the composite of nanoscale silicon and silicon oxide The monomer will not easily deform or become brittle. In addition, a plurality of honeycomb-shaped structures are formed between the plurality of graphene sheets, the plurality of first polymer materials and the plurality of composite monomers of nanoscale silicon and silicon oxide in the entire first-stage carbon silicon ball. The buffer void can absorb the expansion of the composite monomer of nanoscale silicon and silicon oxide, so the entire first-order carbon silicon ball can maintain a small volume expansion for a long time. The outer layer of the first-stage carbon silicon ball is coated with a layer of the second polymer material, and the outside of the second polymer material layer is tightly wrapped by the carbon nanotubes through a mixing process after sintering. This makes the first-stage carbon silicon balls less likely to expand, thus further increasing the bonding force of the overall structure. Because the second polymer material layer is sintered, the sugars are carbonized, which also increases the electrochemical cycle capability of the overall composite carbon silicon negative electrode matrix, thereby improving longer-lasting high-efficiency capacitance and structural maintenance capabilities. Therefore, when the material in this case is used as a negative electrode material, it has a higher capacitance and a longer battery life.

In order to achieve the above purpose, the present invention proposes a method for manufacturing a composite carbon silicon negative electrode substrate, which includes the following steps: Step A: splitting graphene into a plurality of graphene sheets; Step B: splitting the plurality of graphene sheets The tablets are mixed with ethanol and the first polymer material and mixed to produce a viscous polymer graphene mother liquor; Step C: Disperse and crack the silicon and silicon oxide powder into multiple nanoscale composite units of silicon and silicon oxide. body, and then mix the polymer graphene mother liquor with the composite monomers of nanoscale silicon and silicon oxide to form a carbon silicon mother liquor; step D: perform a spray drying process on the carbon silicon mother liquor; that is, the carbon silicon mother liquor After spraying, particles are formed and dried in the particle state; their purpose is to evaporate the original Ethanol in the carbon silicon mother liquor; therefore, a first-order carbon silicon ball is formed, the main structure of which includes the plurality of graphene sheets, the plurality of composite monomers of nanoscale silicon and silicon oxide, and the first polymer material; The first polymer material is used as an adhesive to connect the plurality of graphene sheets and the plurality of composite monomers of nanoscale silicon and silicon oxide; wherein there are a plurality of depressions in the first-stage carbon silicon ball and buffer vacant positions to form multiple honeycomb buffer voids to absorb the expansion of the composite monomer of nanoscale silicon and silicon oxide; Step E: Perform a mixed sintering step, in which the first-stage carbon silicon is The balls, the second polymer material and the carbon nanotubes are mixed and then sintered, or the first-stage carbon silicon balls, the second polymer material are mixed and sintered and then the carbon nanotubes are mixed; step F: The mixed first-stage carbon silicon balls, the second polymer material and the carbon nanotubes are subjected to a special shaping step to form the second-stage carbon silicon balls; Step G: The second-stage carbon silicon balls are heated in a sintering furnace After sintering, amorphous carbon-coated third-stage carbon silica balls are formed; the structure of the third-stage carbon silica balls is that the outer layer of the first-stage carbon silica balls is coated with a layer of the second polymer material. The outer layer formed by the second polymer material is tightly wrapped by carbon nanotubes; the covered second polymer material is sintered during the sintering process, causing the sugars to carbonize, so it also increases the overall third Capacitive capacity of third-order carbon silicon balls.

This case also proposes a composite carbon silicon negative electrode matrix, which includes: a first-order carbon silicon ball, including a plurality of graphene sheets, a plurality of composite monomers of nanoscale silicon and silicon oxide, and a plurality of first polymer materials; The first polymer material is used as an adhesive to connect the plurality of graphene sheets and the plurality of composite monomers of nanoscale silicon and silicon oxide; wherein the plurality of graphene sheets, the plurality of nanoscale silicon A plurality of honeycomb-shaped buffer gaps are formed between the composite monomer of silicon oxide and the plurality of first polymer materials; a second polymer material layer coats the outside of the first-stage carbon silicon ball; The two polymer material layers are sintered to carbonize the sugars to increase the conductivity of the overall composite carbon silicon negative electrode matrix; and a plurality of carbon nanotubes tightly wrap the second polymer material layer; the carbon nanotubes Wrapping the second polymer material layer has a tightening effect, making it difficult for the first-stage carbon silicon balls inside to expand.

The features and advantages of the present invention can be further understood from the following description. Please refer to the accompanying drawings when reading.

1: Composite carbon silicon negative electrode matrix

10:Graphene sheet

20:The first polymer material

30: Composite monomer of nanoscale silicon and silicon oxide

40: The second polymer material

45: The second polymer material layer

50:Carbon nanotubes

60: Buffer gap

100:First stage carbon silicon ball

300:Third stage carbon silicon ball

Figure 1 shows a schematic diagram of the first-stage carbon silicon ball in this case.

Figure 2 shows a schematic cross-sectional view of the third-stage carbon silicon ball in this case.

Figure 3 shows a three-dimensional schematic diagram of the third-stage carbon silicon ball in this case.

Figure 4 shows the step flow chart of the manufacturing process of this case.

Figure 5 shows a schematic cross-sectional view of the composite carbon silicon negative electrode matrix in this case.

Figure 6 shows a schematic three-dimensional view of the composite carbon silicon negative electrode matrix in this case.

Hereby, we would like to give a detailed description of the structural composition of this case, as well as the functions and advantages it can produce, together with the drawings, and give a detailed description of one of the preferred embodiments of this case as follows.

Please refer to FIGS. 1 to 4 , which illustrate the manufacturing method of the composite carbon silicon negative electrode base material of the present invention. FIG. 4 shows a step flow chart of the manufacturing method of the present invention. The manufacturing method includes the following steps:

Crack graphene (graphene) into a plurality of graphene sheets 10 (step 700), where the maximum size of each sheet is less than 3 micrometers (micrometer); the cracking method includes planetary mixing, wet grinding, and high-pressure homogeneous grinding. any of the other methods.

The plurality of graphene sheets 10 are mixed with ethanol and the first polymer material 20 and mixed to generate a viscous polymer graphene mother liquid (step 701). The first polymer material 20 is selected from polymer cellulose sugar materials or polymer unsaturated sugar materials. The weight ratio of the plurality of graphene sheets 10, ethanol, and first polymer material 20 is graphene sheet 10: ethanol: first polymer material 20 = (0.15~0.20): (0.01~0.015): (0.77 ~0.84). The polymer cellulose sugar material or the polymer unsaturated sugar material can be, for example, carboxymethyl cellulose (CMC, Carboxymethyl cellulose), Alginate, polyvinylpyrrolidone (PVP, Polyvinylpyrrolidone), polyvinyl alcohol (PVA, Polyvinyl alcohol), glucose (Glucose), etc.

Silicon and silicon oxide powder (SiO _x , where x is less than 2) are dispersed and cracked into a plurality of composite monomers 30 of nanoscale silicon and silicon oxide, and then the polymer graphene mother liquor is mixed with the plurality of nanoscale silicon and silicon oxide. The silicon composite monomer 30 is oxidized to form a carbon silicon mother liquor (step 702). The mixing method can be pneumatic homogeneous mixing or planetary mixing, which is familiar to the industry, so its content will not be described in detail.

The above carbon silicon mother liquor is subjected to a spray drying process. That is, the carbon silicon mother liquor is sprayed out to form particles, and then dried in the particle state. Its purpose is to evaporate the ethanol in the original carbon silicon mother liquor. Therefore, the first-stage carbon silicon ball 100 is formed, and its main structure includes the plurality of graphene sheets 10, the plurality of composite monomers 30 of nanoscale silicon and silicon oxide, and the first polymer material 20. The first polymer material 20 is used as an adhesive for connecting the plurality of graphene sheets 10 and the plurality of composite monomers 30 of nanoscale silicon and silicon oxide (step 703). As shown in Figure 1. In this structure, the graphene sheet 10 is a tough and elastic structure that does not easily deform, so it can limit the expansion of the composite monomer 30 of nanoscale silicon and silicon oxide, thus making the nanoscale The composite monomer 30 of silicon and silicon oxide will not easily deform or become brittle. In addition, as shown in FIG. 1 , there are gaps between the plurality of graphene sheets 10 , the first polymer material 20 and the composite monomer 30 of nanoscale silicon and silicon oxide in the entire first-stage carbon silicon ball 100 . A plurality of depressions and buffering vacancies form multiple honeycomb-shaped buffering voids 60. These buffering voids 60 can absorb the expansion of the composite monomer 30 of nanoscale silicon and silicon oxide, so the entire first-order carbon silicon ball 100 can maintain a fixed volume for a long time. Therefore, when the material in this case is used as a negative electrode material, it has a higher capacitance and a longer battery life.

The following describes the further process of this case:

In the mixing and sintering step, the first-stage carbon silicon ball 100, the second polymer material 40 and the carbon nanotube 50 (a small amount) are mixed and then sintered, or the first-stage carbon silicon ball 100, After the second polymer material 40 is mixed and sintered, the carbon nanotubes 50 are mixed. (step 704). The first stage carbon silicon ball 100. The weight ratio of the second polymer material 40 and the carbon nanotube 50 is first-stage carbon silicon ball 100: second polymer material 40: carbon nanotube 50=(0.80~0.84): (0.16 ~0.19): (0.0001~0.005). The second polymer material 40 is a polymeric polysaccharide, such as carboxymethyl cellulose (CMC), alginate (Alginate), polyvinylpyrrolidone (PVP), polyvinyl alcohol (PVA), Polyvinyl alcohol), glucose (Glucose). The molecular weight, polymerization degree and viscosity of the second polymer material 40 are higher than those of the first polymer material 20 . The carbon nanotubes 50 are 15~25 μm array carbon tubes with excellent conductivity and relatively complete structure.

The mixed first-stage carbon silicon balls 100, the second polymer material 40 and the carbon nanotubes 50 (a small amount) are subjected to special forming steps, such as VC mixing (ie, mixing by a V-shaped mixer) or spray drying In this way, second-stage carbon silicon balls are formed (step 705).

The second-stage carbon silicon balls are sintered in a sintering furnace to form amorphous carbon-coated third-stage carbon silicon balls 300 (step 706).

The structure of the third-stage carbon silicon ball 300 is that the outer layer of the first-stage carbon silicon ball 100 is coated with a layer of the second polymer material 40 (as shown in FIG. 2 ). The outside of the formed outer layer is tightly wrapped by carbon nanotubes 50 . Since the coated second polymer material 40 is sintered during the sintering process, the sugars are carbonized, thereby increasing the capacitance of the overall third-stage carbon silicon ball 300 . As shown in FIG. 3 , the outer layer formed by wrapping the second polymer material 40 with the carbon nanotube 50 has a tight binding effect, making it difficult for the first-stage carbon silicon ball 100 inside to expand. Therefore, the bonding force of the overall structure is further increased.

As shown in Figures 5 and 6, this case also includes a composite carbon silicon negative electrode matrix 1 formed by the above manufacturing method, which includes:

A first-stage carbon silicon ball 100 includes a plurality of graphene sheets 10 , a plurality of composite monomers 30 of nanoscale silicon and silicon oxide, and a plurality of first polymer materials 20 . The first polymer material 20 is used as an adhesive to connect the plurality of graphene sheets 10 and the plurality of composite monomers of nanoscale silicon and silicon oxide. 30, as shown in Figure 5. The contents of the plurality of graphene sheets 10 , the plurality of composite monomers 30 of nanoscale silicon and silicon oxide, and the plurality of first polymer materials 20 are all greater than 0, and the proportions of their weights can be adjusted as needed. The weight ratio is, for example, graphene sheet 10: composite monomer 30 of nanoscale silicon and silicon oxide: first polymer material 20=(0.19~0.33): (0.47~0.59): (0.20~0.22).

A plurality of honeycomb-shaped buffer gaps 60 are formed between the plurality of graphene sheets 10 , the plurality of composite monomers 30 of nanoscale silicon and silicon oxide, and the plurality of first polymer materials 20 .

The graphene sheet 10 is cracked from graphene into flakes with a maximum size of less than 3 micrometers; the composite monomer 30 of nanoscale silicon and silicon oxide is made of powdery silicon powder surface-coated Formed by coating silicon oxide. The first polymer material 20 is selected from polymer cellulose sugar materials or polymer unsaturated sugar materials. The polymeric cellulose sugar material or the polymeric unsaturated sugar material can be, for example, carboxymethylcellulose alginate, polyvinylpyrrolidone, polyvinyl alcohol, glucose, etc.

A second polymer material layer 45 covers the outside of the first-stage carbon silicon ball 100 . The second polymer material layer 45 is a polymeric polysaccharide, such as carboxymethyl cellulose (CMC), alginate (Alginate), polyvinylpyrrolidone (PVP), polyvinyl alcohol (PVA) , Polyvinyl alcohol), glucose (Glucose). The molecular weight, polymerization degree and viscosity of the second polymer material layer 45 are higher than those of the first polymer material 20 . The second polymer material layer 45 is sintered to carbonize the sugars to increase the electrical conductivity of the overall composite carbon silicon negative electrode matrix 1. The amorphous carbon film also strengthens the structure and anti-expansion ability of the composite material.

A plurality of carbon nanotubes 50 tightly wrap the second polymer material layer 45 . As shown in FIG. 6 , the carbon nanotube 50 wraps the second polymer material layer 45 , which has a tight binding effect so that the first-stage carbon silicon ball 100 inside the carbon nanotube 50 does not easily expand. Therefore, the bonding force of the overall structure is further increased. The carbon nanotubes 50 are 15~25 μm array carbon tubes with excellent conductivity and relatively complete structure.

In the composite carbon silicon negative electrode matrix 1 made by applying the above steps, the graphene sheet 10 is a tough and elastic structure that will not easily deform, so it can limit the composite of nanoscale silicon and silicon oxide. The expansion of the monomer 30 prevents the composite monomer 30 of nanoscale silicon and silicon oxide from easily deforming or becoming brittle. In addition, the plurality of graphene sheets 10 , the plurality of first polymer materials 20 and the plurality of composite monomers 30 of nanoscale silicon and silicon oxide in the entire first-stage carbon silicon ball 100 are formed between The honeycomb buffer gaps 60 can absorb the expansion of the composite monomer 30 of nanoscale silicon and silicon oxide, so the entire first-stage carbon silicon ball 100 can maintain a small volume expansion for a long time. The first-stage carbon silicon ball 100 is coated with a second polymer material layer 45 on its outer layer, and the carbon nanotubes 50 are formed on the outside of the second polymer material layer 45 through a mixing process after sintering. Wrap tightly. The second polymer material layer 45 is sintered to carbonize the sugars, thereby increasing the electrochemical cycle capability of the overall composite carbon silicon negative electrode matrix 1 and thereby improving longer-lasting high-efficiency capacitance and structure maintenance capabilities.

Therefore, when the material in this case is used as a negative electrode material, it has a higher capacitance and a longer battery life.

To sum up, the humanized and considerate design of this case is quite in line with actual needs. Its specific improvement has the existing deficiencies, and it has obvious breakthrough advantages compared to the conventional technology, and it does have an improvement in efficacy, and it is not easy to achieve. This case has not been published or disclosed in domestic or foreign documents or markets, and it complies with the provisions of the patent law.

The above detailed description is a specific description of one possible embodiment of the present invention. However, this embodiment is not intended to limit the patent scope of the present invention. Any equivalent implementation or modification that does not depart from the technical spirit of the present invention shall be included in within the scope of the patent in this case.

1: Composite carbon silicon negative electrode matrix

45: The second polymer material layer

50:Carbon nanotubes

Claims (15)

A method for manufacturing a composite carbon silicon negative electrode base material, including the following steps: Step A: Crack graphene into a plurality of graphene sheets; Step B: Mix the plurality of graphene sheets with ethanol and a first polymer Materials are mixed to produce a viscous polymer graphene mother liquor; the first polymer material is selected from polymer cellulose sugars or polymer unsaturated sugars, and the polymer cellulose sugars Or the polymer unsaturated sugar material is selected from carboxymethyl cellulose, alginate, polyvinylpyrrolidone, polyvinyl alcohol, and glucose; step C: disperse and crack the silicon and silicon oxide powder into multiple nanoscale silicon and oxidize The composite monomer of silicon is then mixed with the polymer graphene mother liquor and the composite monomers of nanoscale silicon and silicon oxide to form a carbon silicon mother liquor; Step D: The above carbon silicon mother liquor is spray-dried; that is, After the carbon silicon mother liquor is sprayed out, it forms particles and is dried in the particle state; the purpose is to evaporate the ethanol originally in the carbon silicon mother liquor; therefore, a first-order carbon silicon ball is formed, the main structure of which includes the plurality of graphene sheets. , the plurality of composite monomers of nanoscale silicon and silicon oxide and the first polymer material; wherein the first polymer material is used as an adhesive to connect the plurality of graphene sheets and the plurality of nanometer A composite monomer of nano-grade silicon and silicon oxide; there are a plurality of depressions and buffer vacancies in the first-stage carbon silicon ball, forming a plurality of honeycomb-shaped buffer voids for absorbing the nano-grade silicon and silicon oxide. The expansion of the composite monomer; Step E: Perform a mixing and sintering step, which is to first mix and sinter the first-stage carbon silicon balls and the second polymer material, and then mix the carbon nanotubes; the second polymer material is a polymer Polysaccharide; wherein the polymer polysaccharide is selected from carboxymethylcellulose, alginate, polyvinylpyrrolidone, polyvinyl alcohol, and glucose; Step F: Combine the mixed first-stage carbon silicon balls, the second-highest The molecular material and carbon nanotubes are mixed with VC or spray dried to form second-stage carbon silicon balls; Step G: The second-stage carbon silicon balls are sintered in a sintering furnace to form amorphous carbon coating The third stage carbon silicon ball; The structure of the third-stage carbon silicon ball is that the outer layer of the first-stage carbon silicon ball is coated with a layer of the second polymer material, and the outer layer formed of the second polymer material is wrapped by carbon nanotubes. ; Among them, the second polymer material of the coating is sintered during the sintering process, causing the sugar to be carbonized, so it also increases the capacitance capacity of the overall third-order carbon silicon ball. The manufacturing method of composite carbon silicon negative electrode substrate as described in claim 1, wherein in step A, the maximum size of each graphene sheet is less than 3 micrometers. The manufacturing method of composite carbon silicon negative electrode substrate as described in claim 1, wherein in step A, the graphene cracking method is selected from any one of planetary mixing, wet grinding, high-pressure homogeneous grinding, etc. . The manufacturing method of composite carbon silicon negative electrode substrate as described in claim 1, wherein in step B, the weight ratio of the plurality of graphene sheets, ethanol, and the first polymer material is graphene sheet: ethanol: first A polymer material = (0.15~0.20): (0.01~0.015): (0.77~0.84). The manufacturing method of composite carbon silicon negative electrode substrate as claimed in claim 1, wherein in step C, the method of mixing the polymer graphene mother liquor with the plurality of composite monomers of nanoscale silicon and silicon oxide is selected from the group consisting of: Either pneumatic homogeneous mixing or planetary mixing. The manufacturing method of composite carbon silicon negative electrode substrate as described in claim 1, wherein in step C, the silicon oxide powder is SiO _x , where x is less than 2. The manufacturing method of composite carbon silicon negative electrode substrate as described in claim 1, wherein in step E, the weight ratio of the first-stage carbon silicon ball, the second polymer material and the carbon nanotube is First-order carbon silicon ball: second polymer material: carbon nanotube = (0.80~0.84): (0.16~0.19): (0.0001~0.005). The manufacturing method of composite carbon silicon negative electrode substrate as claimed in claim 1, wherein in step E, the molecular weight, degree of polymerization and viscosity of the second polymer material are higher than those of the first polymer material. The manufacturing method of composite carbon silicon negative electrode substrate as described in claim 1, wherein in step E, the carbon nanotubes are 15~25 μm array carbon tubes with conductivity and complete structure. A composite carbon silicon negative electrode matrix prepared by the manufacturing method described in any one of claims 1 to 9, including: a first-order carbon silicon ball, including a plurality of graphene sheets, a plurality of nanoscale silicon and A composite monomer of silicon oxide and a plurality of first polymer materials; the first polymer material is used as an adhesive to connect the plurality of graphene sheets and the plurality of composite monomers of nanoscale silicon and silicon oxide; A plurality of honeycomb buffer gaps are formed between the plurality of graphene sheets, the plurality of composite monomers of nanoscale silicon and silicon oxide, and the plurality of first polymer materials; the first polymer material is selected from High molecular cellulose sugar material or high molecular unsaturated sugar material; the high molecular cellulose sugar material or high molecular unsaturated sugar material is selected from carboxymethyl cellulose, alginate, polyvinylpyrrolidone, polyethylene Alcohol, glucose; a second polymer material layer coating the outside of the first-stage carbon silicon ball; the second polymer material layer is sintered to carbonize the sugars to increase the overall composite carbon silicon negative electrode matrix The conductive ability; the second polymer material layer is a polymer polysaccharide; wherein the polymer polysaccharide is selected from carboxymethylcellulose, alginate, polyvinylpyrrolidone, polyvinyl alcohol, glucose; and a plurality of The carbon nanotube wraps the second polymer material layer; the carbon nanotube wraps the second polymer material layer, which has a tight binding effect so that the first-order carbon silicon ball inside is not easy to expand. The composite carbon silicon negative electrode matrix according to claim 10, wherein the weight ratio of the plurality of graphene sheets, the plurality of composite monomers of nanoscale silicon and silicon oxide, and the plurality of first polymer materials is Graphene sheet: composite monomer of nanoscale silicon and silicon oxide: first polymer material = (0.19~0.33): (0.47~0.59): (0.20~0.22). The composite carbon silicon negative electrode matrix according to claim 10, wherein the graphene sheet is cracked from graphene into flakes with a maximum size of less than 3 micrometers. The composite carbon silicon negative electrode matrix according to claim 10, wherein the composite single system of nanoscale silicon and silicon oxide is formed by coating the surface of powdery silicon powder with silicon oxide. The composite carbon silicon negative electrode matrix according to claim 10, wherein the molecular weight, polymerization degree and viscosity of the second polymer material layer are higher than those of the first polymer material. The composite carbon silicon negative electrode matrix as described in claim 10, wherein the carbon nanotubes are 15~25 μm array carbon tubes with conductivity and complete structure.

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