Composite electrode particles coated with a silicon layer, a carbon layer, and a zinc oxide layer.

Abstract

The present invention provides composite electrode particles coated with a silicon layer, a carbon layer, and a zinc oxide layer. [Solution] Used as an electrode for a solid or semi-solid battery. The composite electrode particles consist of porous carbon particles having a plurality of holes on their surface, and a continuous thin film silicon layer covering the outer surface of the porous carbon particles, wherein the silicon material of the silicon layer comprises a silicon layer filling the holes of the porous carbon particles, an amorphous carbon layer having a continuous structure and covering the outer surface of the silicon layer, and a zinc oxide layer that is a continuous thin film formed of a plurality of zinc oxide molecules and covering the outer surface of the amorphous carbon layer. Even if lithium ions are filled into the silicon layer and the silicon layer expands, the zinc oxide layer protects the structure of the inner layer with its good ductility. The outer surface of the zinc oxide layer is further covered with an aluminum oxide layer. The aluminum oxide layer is a continuous thin film formed of a plurality of aluminum oxide molecules.

Description

Technical Field

[0001] The present invention relates to electrode particles, and more particularly to a composite electrode particle coated with a silicon layer, a carbon layer and zinc oxide.

Background Art

[0002] [[ID=1२]]A battery is composed of a positive electrode and a negative electrode. The negative electrode mainly includes a negative electrode substrate and a negative electrode slurry layer coated on the negative electrode substrate. The negative electrode slurry layer includes a negative electrode slurry having a binder and a plurality of negative electrode particles. The negative electrode particles are mainly used for the negative electrode of a solid or semi-solid battery. The negative electrode particles have conductive auxiliary or conductive properties, enable free electrons to move in the negative electrode slurry, and effectively achieve the purpose of conduction by preventing excessive energy consumption due to internal resistance.

Summary of the Invention

Problems to be Solved by the Invention

[0003] The negative electrode particles are distributed in the negative electrode slurry, and the outer surfaces of these negative electrode particles are coated with silicon particles. However, in the reaction process of the battery, when lithium ions enter the silicon particles and the volume of the silicon particles expands, the silicon particles may expand up to 400 times their original size, and the volume of the entire negative electrode particles changes significantly. Such a huge volume expansion damages the entire negative electrode particles and reduces the battery performance.

[0004] Therefore, the inventor of the present invention believes that the above-mentioned drawbacks can be improved, and as a result of intensive studies, by improving the volume expansion of the negative electrode particles, the negative electrode of the conventional solid battery has higher battery performance, and a design for further improving the battery performance is provided.

[0005] This invention has been made in view of these circumstances, and its objective is to provide composite electrode particles coated with a silicon layer, a carbon layer, and a zinc oxide layer. [Means for solving the problem]

[0006] To solve the above problems, composite electrode particles coated with a silicon layer, a carbon layer, and a zinc oxide layer according to a certain aspect of the present invention are used as electrodes for solid or semi-solid batteries, and the composite electrode particles are Porous carbon particles having multiple holes on their surface, A silicon layer covering the outer surface of the porous carbon particles, wherein the silicon layer is a continuous thin film, and the silicon material of the silicon layer is a silicon layer filling the holes of the porous carbon particles. An amorphous carbon layer covering the outer periphery of the silicon layer, wherein the amorphous carbon layer has a continuous structure formed of amorphous carbon, has good conductivity, suppresses the overall expansion of the electrode particles, and is used to prevent the silicon layer from expanding excessively and causing the composite electrode particles to burst when lithium ions are filled into the silicon layer. The zinc oxide layer covers the outer surface of the amorphous carbon layer, wherein the zinc oxide layer is a continuous thin film formed of multiple zinc oxide molecules, and the zinc oxide layer is a continuous dense layer having good conductivity and metallic hardness, and is malleable and intact. [Effects of the Invention]

[0007] As the present invention is configured as described above, it produces the following effects. The present invention suppresses the expansion of the overall volume of the composite electrode particles by coating the outer surface of the porous carbon particles with a silicon layer, thereby preventing the composite electrode particles from expanding excessively and becoming damaged. Furthermore, by further coating the outer surface of the silicon layer with an amorphous carbon layer, and since the amorphous carbon layer has suitable conductivity, it is possible to suppress the expansion of the composite electrode particles and prevent the volume of the composite electrode particles from expanding excessively when lithium ions are filled into the silicon layer. By further coating the outer surface of the amorphous carbon layer with a zinc oxide layer, which has good conductivity and metal-like ductility, even if the silicon layer expands when lithium ions are filled into the silicon layer, the zinc oxide layer protects the structure of the inner layer with its good ductility. In this way, the present invention significantly reduces the rate of fragmentation of the composite electrode particles by the multilayer coating structure described above.

[0008] Other features of the present invention will be made clearer by description in this specification and the accompanying drawings. [Brief explanation of the drawing]

[0009] [Figure 1] This is a schematic cross-sectional view showing composite electrode particles according to one embodiment of the present invention. [Figure 2] This is a schematic diagram showing porous carbon particles according to one embodiment of the present invention. [Figure 3] This is a schematic diagram showing electrode particles coated with carbon nanotubes according to one embodiment of the present invention. [Figure 4] This is an application example showing composite electrode particles coated with a silicon layer, a carbon layer, and a zinc oxide layer according to one embodiment of the present invention. [Figure 5] This is a schematic diagram showing composite electrode particles coated with a silicon layer, a carbon layer, and a zinc oxide layer according to another embodiment of the present invention. [Modes for carrying out the invention]

[0010] Embodiments of the present invention will be described in detail below with reference to the drawings. It goes without saying that the present invention is not limited to the following examples, and can be modified as needed without departing from the spirit of the invention.

[0011] First, an example of a specific embodiment of the composite electrode particles coated with a silicon layer, a carbon layer, and a zinc oxide layer according to the present invention will be described with reference to Figures 1 to 5.

[0012] The composite electrode particles coated with silicon particles, a carbon layer, and a zinc oxide layer according to the present invention are mainly used as electrodes for solid or semi-solid batteries, and in particular as the negative electrode 10 of the solid or semi-solid battery. The negative electrode 10 comprises a negative electrode substrate 11 on which the material of the negative electrode 10 is placed, and a negative electrode slurry layer 13 coated on the negative electrode substrate 11 (see Figure 4). The negative electrode slurry layer 13 contains a negative electrode slurry 12 as a binder and a plurality of composite electrode particles 40. The weight percentage of the total weight of the plurality of composite electrode particles 40 in the negative electrode slurry layer 13 is in the range of 90 wt% to 99 wt%. The particle size of the composite electrode particles 40 is in the range of 5 μm to 12 μm.

[0013] The composite electrode particle 40 is composed of the following elements (see Figure 1).

[0014] The porous carbon particles 30 have a size in the range of 5 μm to 10 μm and have multiple holes 31 on their surface (see Figure 2). The porous carbon particles 30 are made of graphite or the like.

[0015] The silicon layer 32 covers the outer surface of the porous carbon particles 30. The silicon layer 32 is a continuous thin film formed of multiple silicon materials, that is, a thin film having a smooth surface. The silicon material of the silicon layer 32 fills the holes 31 of the porous carbon particles 30. The thickness of the silicon layer 32 is less than 15 nm. The weight ratio of the silicon layer 32 to the porous carbon particles 30 is in the range of 1:9 to 1:12.

[0016] The amorphous carbon layer 36 covers the outer surface of the silicon layer 32. The amorphous carbon layer 36 is a continuous structure formed of amorphous carbon, that is, a film layer having a smooth surface. The radial thickness of the amorphous carbon layer 36 is in the range of 10 nm to 20 nm. Because the amorphous carbon layer 36 has suitable conductivity, it can suppress the overall expansion of the electrode particles and prevent the volume from expanding excessively when lithium ions are filled into the silicon layer 32, which could cause the electrode particles to burst. The amorphous carbon of the amorphous carbon layer 36 is hard carbon or soft carbon formed by sintering deesterification of an organic resin system, or hard carbon or soft carbon formed by sintering deesterification of an organic carbohydrate.

[0017] During the reaction process of the battery, lithium ions enter the silicon layer 32 and the volume of the silicon layer 32 expands, which can cause the silicon layer 32 to expand up to 400 times its original size, resulting in a significant change in the volume of the composite electrode particles 40. To prevent the silicon layer 32 from expanding excessively and destroying the composite electrode particles 40, the outer surface of the silicon layer 32 is covered with the amorphous carbon layer 36 having a continuous structure, thereby achieving a two-layer protective effect and preventing damage to the composite electrode particles 40.

[0018] The zinc oxide (ZnO) layer 37 covers the outer surface of the amorphous carbon layer 36. The zinc oxide layer 37 is a continuous thin film formed of multiple zinc oxide molecules, that is, a film layer having a smooth surface, and the entire layer forms the composite electrode particles 40. The radial thickness of the zinc oxide layer 37 is in the range of 8 nm to 12 nm. The zinc oxide layer 37 has good conductivity, is a continuous dense layer with metallic hardness, and has good malleability and integrity, so it can protect the structure of the inner layer, maintain the integrity of the composite electrode particles 40, and prevent damage.

[0019] The present invention further includes a plurality of carbon nanotubes (CNT) 42 that coat the periphery of the composite electrode particles 40, forming electrode particles 45 coated with carbon nanotubes (see FIG. 3). The length of each carbon nanotube 42 is less than 5 μm.

[0020] Carbon nanotubes are very good conductive materials. When they adhere to the composite electrode particles 40, they form a structure like wool yarn. The carbon nanotubes 42 are used to increase the electron conductivity and conduct electrons on the composite electrode particles 40. Carbon nanotubes have extremely high conductivity. Since lithium ions pass through the carbon nanotubes 40 and conduct between different composite electrode particles 40 of the electrode, the conductivity of the entire electrode is increased. The weight ratio of the total weight of the plurality of carbon nanotubes 42 to the weight of the composite electrode particles 40 is in the range between 1:99 and 0.2:99.8.

[0021] FIG. 5 is a schematic diagram showing composite electrode particles coated with a silicon layer, a carbon layer, and a zinc oxide layer according to another embodiment of the present invention. The composite electrode particles 40 further include an aluminum oxide (Al2O3) layer 38 that coats the periphery. The aluminum oxide layer 38 is a continuous thin film formed of a plurality of aluminum oxide molecules, that is, a film layer having a smooth surface, and coats the outer surface of the zinc oxide layer 37 of the composite electrode particles 40. The radial thickness of the aluminum oxide layer 38 is less than 5 nm. The aluminum oxide layer 38 can increase the conductivity of the composite electrode particles 40 and the wettability of the electrolyte. The outer surface of the aluminum oxide layer 38 is further coated with the plurality of carbon nanotubes 42, forming electrode particles 45 entirely coated with carbon nanotubes.

[0022] The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope shown in the claims. Embodiments obtained by appropriately combining the technical means disclosed in different embodiments are also included in the technical scope of the present invention.

Explanation of Reference Numerals

[0023] 10 negative electrode 11 Negative electrode substrate 12. Negative electrode slurry 13. Negative electrode slurry layer 30 Porous carbon particles 31 holes 32 Silicon Layers 36 Amorphous carbon layer 37. Zinc oxide layer 38. Aluminum Oxide Layer 40 Composite electrode particles 42 Carbon nanotubes 45 Electrode particles coated with carbon nanotubes

Claims

1. Composite electrode particles coated with a silicon layer, a carbon layer, and a zinc oxide layer, used as electrodes for solid or semi-solid batteries, Porous carbon particles having multiple holes on their surface, A silicon layer covering the outer surface of the porous carbon particles, wherein the silicon layer is a continuous thin film, and the silicon material of the silicon layer is a silicon layer filling the holes of the porous carbon particles. An amorphous carbon layer covering the outer periphery of the silicon layer, wherein the amorphous carbon layer has a continuous structure formed of amorphous carbon, has good conductivity, suppresses the overall expansion of the electrode particles, and is used to prevent the silicon layer from expanding excessively and causing the composite electrode particles to burst when lithium ions are filled into the silicon layer. A composite electrode particle coated with a silicon layer, a carbon layer, and a zinc oxide layer, characterized in that the zinc oxide layer covers the outer surface of the amorphous carbon layer, the zinc oxide layer is a continuous thin film formed of a plurality of zinc oxide molecules, the zinc oxide layer is a continuous dense layer having good conductivity and metallic hardness, and the zinc oxide layer has ductility and integrity.

2. The composite electrode particle coated with a silicon layer, a carbon layer, and a zinc oxide layer according to claim 1, characterized in that the particle size of the porous carbon particles is in the range of 5 μm to 10 μm.

3. The composite electrode particle coated with a silicon layer, a carbon layer, and a zinc oxide layer according to claim 1, characterized in that the thickness of the silicon layer is less than 15 nm.

4. The composite electrode particle coated with a silicon layer, a carbon layer, and a zinc oxide layer according to claim 1, characterized in that the weight ratio of the silicon layer and the porous carbon particles is in the range of 1:9 to 1:

12.

5. The composite electrode particle coated with a silicon layer, a carbon layer, and a zinc oxide layer according to claim 1, characterized in that the radial thickness of the amorphous carbon layer is in the range of 10 nm to 20 nm.

6. The amorphous carbon in the amorphous carbon layer is selected from hard carbon or soft carbon formed by sintering deesterification of an organic resin system, or hard carbon or soft carbon formed by sintering deesterification of an organic carbohydrate, as described in claim 1, comprising a silicon layer, a carbon layer, and a zinc oxide layer.

7. The composite electrode particle coated with a silicon layer, a carbon layer, and a zinc oxide layer according to claim 1, characterized in that the radial thickness of the zinc oxide layer is in the range of 8 nm to 12 nm.

8. The composite electrode particles coated with a silicon layer, a carbon layer, and a zinc oxide layer according to claim 1, characterized in that the composite electrode particles are used as the negative electrode of a solid or semi-solid battery.

9. The composite electrode particle coated with a silicon layer, a carbon layer, and a zinc oxide layer according to claim 1, further comprising a plurality of carbon nanotubes (CNTs) that coat the outer surface of the composite electrode particle, thereby forming an electrode particle that coats the carbon nanotubes.

10. The composite electrode particle coated with a silicon layer, a carbon layer, and a zinc oxide layer according to claim 9, characterized in that each carbon nanotube is less than 5 μm in length, forms a yarn-like structure when attached to the composite electrode particle, and the plurality of carbon nanotubes are used to enhance electronic conductivity.

11. The composite electrode particle coated with a silicon layer, a carbon layer, and a zinc oxide layer according to claim 9, characterized in that the weight ratio of the total weight of the plurality of carbon nanotubes to the weight of the composite electrode particle is in the range of 1:99 to 0.2:99.

8.

12. Aluminum oxide (Al ２ O ３ A composite electrode particle coated with a silicon layer, a carbon layer, and a zinc oxide layer according to any one of claims 1 to 8, further comprising a layer wherein the aluminum oxide layer is a continuous thin film formed of a plurality of aluminum oxide molecules, and covers the outer surface of the zinc oxide layer of the composite electrode particle.

13. The composite electrode particle coated with a silicon layer, a carbon layer, and a zinc oxide layer according to claim 12, characterized in that the radial thickness of the aluminum oxide layer is less than 5 nm.

14. The composite electrode particle coated with a silicon layer, a carbon layer, and a zinc oxide layer according to claim 12, further comprising a plurality of carbon nanotubes that cover the outer surface of the aluminum oxide layer, thereby forming electrode particles that cover the carbon nanotubes.

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