Continuous production device and production method of silicon-carbon negative electrode material

Abstract

The invention relates to the technical field of production of silicon-carbon negative electrode materials, in particular to a continuous production device and method for preparing a silicon-carbon negative electrode material by taking porous carbon, silane and hydrocarbon gas as raw materials. The device comprises fluidized beds A1 and B1, storage tanks A2, A4, B2 and B4, cyclone separators A3, B3 and C2 and a heat exchanger C1, and stable fluidization and continuous production of materials are realized through the design of the multi-section reducing fluidized bed. The method comprises the following steps: carrying out silane cracking and silicon embedding on porous carbon, carrying out hydrocarbon gas cracking and carbon coating, cooling and separating, and finally obtaining the silicon-carbon negative electrode material with high capacity and high initial coulombic efficiency. The equipment adaptability can be remarkably improved, the service life is prolonged, efficient and continuous production is achieved, and the equipment is suitable for industrial-scale application.

Description

Technical Field

[0001] The present invention relates to the technical field of production of silicon-carbon negative electrode materials, and in particular to a continuous production device and production method for preparing silicon-carbon negative electrode materials using porous carbon, silane and hydrocarbon gas as raw materials, which is suitable for the industrial production of silicon-carbon negative electrode materials. Background Art

[0002] Lithium-ion batteries, due to their high energy density, low self-discharge rate, long cycle life, and environmentally friendly design, have become indispensable energy storage devices in modern technology and are widely used in electric vehicles, smartphones, and other power tools. However, the theoretical specific capacity of graphite, a conventional lithium-ion battery anode material, is only 372 mAh / g, which is insufficient to meet the current demands for long-range driving in electric vehicles and other high-performance electric devices. Silicon-carbon anode materials, due to their high theoretical specific capacity (silicon's theoretical specific capacity is as high as 4200 mAh / g, 10 times that of graphite) and low electrochemical lithium insertion potential, have become highly promising anode materials for next-generation lithium-ion batteries. Furthermore, porous carbon and a carbon coating effectively limit the volume expansion of silicon during lithium insertion and deintercalation, while providing a conductive network for silicon, significantly improving the conductivity and structural stability of silicon-carbon anode materials. Currently, a common method for preparing silicon-carbon anode materials is to use porous carbon, silane, and hydrocarbon gas as raw materials. Silicon, generated by the decomposition of silane, is embedded within the pores of the porous carbon via chemical vapor deposition, and the carbon generated by the decomposition of the hydrocarbon gas is then coated on the surface.

[0003] However, the existing technology for producing silicon-carbon negative electrode materials has many shortcomings. The common fluidized bed device in China cannot achieve continuous production. Its structure is usually a single-stage variable diameter design, which only contains a single fluidizing zone and a single expansion section, resulting in a limited adaptability to different porous carbon flow rates. In addition, frequent heating and cooling operations not only reduce production efficiency, but also have a serious impact on the service life of key components of the equipment. These problems limit the large-scale industrial application of silicon-carbon negative electrode materials, and there is an urgent need to develop a new device and method that can achieve continuous production and improve equipment adaptability and stability.

[0004] The present invention aims to overcome the aforementioned shortcomings of the prior art by proposing a continuous production apparatus and method using porous carbon, silane, and hydrocarbon gases as raw materials. Through a multi-stage variable-diameter fluidized bed design and an optimized process flow, this method achieves efficient and stable production of silicon-carbon anode materials while improving the product's consistency and electrochemical performance. This not only addresses the issue of insufficient continuous production capacity in the prior art but also significantly extends the equipment's service life, providing a new solution for the industrialized production of silicon-carbon anode materials. Summary of the Invention

[0005] The present invention addresses the shortcomings of the prior art fluidized bed, such as its inability to achieve continuous production, its limited adaptability to porous carbon flow rates, and its impact on equipment life due to frequent temperature increases and decreases. The present invention provides a continuous production device and method for preparing silicon-carbon negative electrode materials using porous carbon, silane, and hydrocarbon gas as raw materials. The specific solution is as follows: A continuous production device for silicon-carbon negative electrode materials comprises at least two stages of fluidized bed reaction units connected in series, wherein the fluidized bed reaction units comprise a fluidized bed, a first storage tank, a cyclone separator, and a second storage tank, which are sequentially connected via pipelines. The material outlet of the last-stage fluidized bed reaction unit is sequentially connected to a heat exchanger C1 and a cyclone separator C2 via pipelines. The fluidized bed adopts a multi-stage variable diameter design, with each stage comprising a constant diameter zone and a variable diameter zone.

[0006] The multi-stage variable-diameter design of the fluidized bed allows the airflow velocity to gradually increase from top to bottom, thereby matching the fluidization requirements of materials of varying densities. This design not only expands the flow rate range for porous carbon but also improves the stability of the material within the fluidized bed, preventing blockage or sedimentation caused by flow rate mismatches. The coolant input line of heat exchanger C1 introduces a cooling medium for heat exchange with the final product material.

[0007] As a preferred solution, the continuous production device includes two stages of fluidized bed reaction units connected in series.

[0008] Furthermore, the diameter of the internal constant diameter zone of the fluidized bed decreases from top to bottom, and the diameter reduction ratio each time is between 10% and 25%.

[0009] Furthermore, the angle α between the variable diameter zone of the fluidized bed and the vertical direction ranges from 30° to 60°.

[0010] Furthermore, a gas distribution plate is installed in the constant diameter area at the bottom of the fluidized bed to evenly distribute the airflow from the bottom, ensuring a uniform flow field within the fluidized bed and sufficient contact between the material and the reaction gas. This design significantly improves reaction efficiency and ensures product uniformity.

[0011] Furthermore, the device is suitable for processing porous carbon materials with a specific surface area ranging from 1600 m² / g to 2000 m² / g and a pore volume ranging from 0.7 cm³ / g to 0.9 cm³ / g.

[0012] Furthermore, the fluidized bed adopts a three-stage variable diameter design.

[0013] In addition, the present invention also provides a method for producing silicon-carbon negative electrode materials using the above-mentioned continuous production device, comprising the following steps: (1) blowing the raw porous carbon along the pipeline with an inert gas and adding it to the fluidized bed A1 of the first-stage fluidized bed reaction unit, and at the same time introducing a mixed gas of silane and inert gas into the fluidized bed A1 at a gas flow ratio of 1:(4-8), maintaining the fluidized bed temperature at 500-600°C, and reacting for 6-8 hours; (2) After the materials generated in the first-stage fluidized bed reaction unit are separated and treated, the solid material A is blown along the pipeline by inert gas into the fluidized bed B1 of the second-stage fluidized bed reaction unit. At the same time, a mixture of hydrocarbon gas and inert gas is introduced into the fluidized bed B1 at a gas flow ratio of 1: (2-5), and the fluidized bed temperature is maintained at 550-650°C for 2-4 hours. (3) The solid material B produced in the secondary fluidized bed reaction unit after separation treatment is blown along the pipeline by inert gas to the heat exchanger C1, and after cooling, the solid material C is separated to obtain the silicon-carbon negative electrode material.

[0014] Furthermore, the inert gas is one or more of nitrogen, argon and helium.

[0015] Furthermore, the heat exchanger C1 introduces a coolant through a pipeline to cool the material, and the coolant is one of cooling water and Freon.

[0016] Furthermore, the specified temperature of the fluidized bed A1 is 560°C; the specified temperature of the fluidized bed B1 is 600°C.

[0017] In summary, the main advantages of the present invention are as follows: The structural design of the multi-stage variable diameter fluidized bed of the present invention adapts to a wider range of flow rates for different porous carbons. The design of the production device with multiple fluidized reaction units connected in series reduces the need for frequent heating and cooling of the equipment, significantly extending the service life of key components. The continuous production method and precise process control of the present invention provide an efficient and stable solution for preparing silicon-carbon anode materials. The entire production process realizes the continuous production of silicon-carbon anode materials, greatly improving production efficiency and reducing costs. It is suitable for industrial-scale production and has important economic and social value. (3) The silicon-carbon negative electrode material prepared by the present invention has good product consistency, good uniformity of silicon deposition and carbon coating, high capacity, high first coulombic efficiency and good electrochemical performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 Schematic diagram of the structure of a continuous production device for producing silicon-carbon negative electrode materials; Figure 2 Schematic diagram of the internal structure of fluidized bed A1 (B1); Figure 3 Schematic diagram of the structure of the gas distribution plate a1 (b1); Figure 4 This is the first charge and discharge curve of the silicon-carbon negative electrode material in Example 1; Figure 5 This is a coulombic efficiency performance diagram of the silicon-carbon negative electrode material in Example 1 after multiple cycles.

[0019] The reference numerals are as follows: A1, B1: fluidized bed; A2, A4, B2, B4: storage tanks; A3, B3, C2: cyclone separators; C1: heat exchanger; 101: air inlet and feed pipes of fluidized bed A1; 102: The gas outlet pipe of fluidized bed A1 is connected to the silane waste gas treatment pipe; 103: air inlet pipe of fluidized bed A1; 104: The discharge pipe of fluidized bed A1 is connected to storage tank A2; 105: air inlet pipe of tank A2; 106: The gas outlet and material outlet pipeline of the storage tank A2 is connected to the cyclone separator A3; 107: The outlet pipe of cyclone separator A3 is connected to the silane waste gas treatment pipe; 108: The discharge pipe of cyclone separator A3 is connected to storage tank A4; 109: air intake line of tank A4; 201: air inlet and feed pipes of fluidized bed B1; 202: The gas outlet pipe of the fluidized bed B1 is connected to the hydrocarbon waste gas treatment pipe; 203: air inlet pipe of fluidized bed B1; 204: The discharge pipe of the fluidized bed B1 is connected to the storage tank B2; 205: air inlet pipe of tank B2; 206: gas outlet and material outlet pipeline of storage tank B2, connected to cyclone separator B3; 207: The outlet pipe of the cyclone separator B3 is connected to the hydrocarbon waste gas treatment pipe; 208: The discharge pipe of cyclone separator B3 is connected to storage tank B4; 209: air intake line of tank B4; 301: coolant input line of heat exchanger C1; 302: Shell-side gas and material outlet pipelines of heat exchanger C1, connected to cyclone separator C2; 304: Gas and material outlet pipes of storage tank B4, connected to heat exchanger C1; 305: outlet pipe of cyclone separator C2; 306: discharge pipe of cyclone separator C2; a1, b1: gas distribution plates of fluidized beds A1 and B1; a2, b2: valves located on pipeline 104 and pipeline 204 respectively. DETAILED DESCRIPTION

[0020] The present invention relates to a continuous production device and method for producing silicon-carbon negative electrode materials. Through the design of a multi-stage variable diameter fluidized bed, optimization of a gas distribution plate, a continuous process flow and precise parameter control, efficient industrial production of silicon-carbon negative electrode materials using porous carbon, silane and hydrocarbon gas as raw materials is achieved. Figure 1 To the attached Figure 5 Specific embodiments of the present invention are described in detail.

[0021] like Figure 1 As shown, the continuous device of the present invention includes a fluidized bed A1, a storage tank A2, a cyclone separator A3, a storage tank A4, a fluidized bed B1, a storage tank B2, a cyclone separator B3, a storage tank B4, a heat exchanger C1 and a cyclone separator C2. The various components are connected by pipelines to form a complete process flow. Among them, pipeline 101 is used to transport the porous carbon and inert gas mixture to the fluidized bed A1, pipeline 102 connects the fluidized bed A1 and the silane waste gas treatment pipeline, which is used to discharge the reaction waste gas; pipeline 103 is the air inlet pipeline of the fluidized bed A1, which is used to introduce a mixture of silane and inert gas; pipeline 104 connects the fluidized bed A1 and the storage tank A2, which is used to transport the material from the fluidized bed A1 to the storage tank A2; pipeline 105 is the air inlet pipeline of the storage tank A2, It is used to purge the material to the next process step with inert gas; pipeline 106 connects storage tank A2 and cyclone separator A3 for transporting material and gas; pipeline 107 connects cyclone separator A3 and the silane waste gas treatment pipeline for exhausting waste gas; pipeline 108 connects cyclone separator A3 and storage tank A4 for transporting the separated material; pipeline 109 is the air inlet pipeline for storage tank A4 and is used to purge the material to fluidized bed B1 with inert gas. Similarly, pipelines 201 to 209 constitute the connection between fluidized bed B1 and its related storage tanks and cyclone separators, used to realize the process of cracking hydrocarbon gas to produce carbon coating. Pipelines 301 to 306 constitute the process part of cooling and final discharge.

[0022] Both fluidized bed A1 and fluidized bed B1 adopt a multi-stage variable diameter design, preferably a three-stage structure, each of which includes a constant diameter area and a variable diameter area. Figure 2As shown, the internal diameter of the fluidized bed decreases from top to bottom, with the diameter reduction ratio of each constant diameter zone ranging from 10% to 25%, preferably 15%. The angle α between the variable diameter zone and the vertical direction ranges from 30° to 60°, preferably 45°. This design allows the air flow rate to gradually increase from top to bottom, thereby matching the fluidization requirements of materials with different densities. In particular, a gas distribution plate a1 or b1 (such as Figure 3 The gas distribution plate (as shown) evenly distributes the gas flow from the bottom, ensuring a uniform flow field within the fluidized bed. Below the gas distribution plate, an inlet pipe 103 or 203 is provided for introducing the reaction gas into the fluidized bed. This design significantly improves reaction efficiency and ensures product uniformity.

[0023] In practice, the porous carbon in pipeline 101 has specific parameters: a specific surface area ranging from 1600 m² / g to 2000 m² / g, preferably 1800 m² / g; a pore volume ranging from 0.7 cm³ / g to 0.9 cm³ / g, preferably 0.8 cm³ / g; and a pore size distribution dominated by micropores. The porous carbon is mixed with an inert gas and then introduced into fluidized bed A1 via pipeline 101. The amount of inert gas used is sufficient to purge the porous carbon into the fluidized bed; a specific ratio is not required. The inert gas is selected from one or more combinations of nitrogen, argon, or helium. The flow ratio of silane to inert gas in pipeline 103 is 1:(4-8), preferably 1:6. The flow ratio of hydrocarbon gas to inert gas in pipeline 203 is 1:(2-5), preferably 1:3.5. The hydrocarbon gas is selected from acetylene, propyne, ethylene, or methane, preferably acetylene.

[0024] The specific operating principle is as follows: First, inert gas transports porous carbon to fluidized bed A1 via pipeline 101. Simultaneously, a mixture of silane and inert gas is introduced via pipeline 103. Fluidized bed A1 operates within a temperature range of 500°C to 600°C, preferably 560°C. At this high temperature, silane decomposes to form silicon particles, which are embedded within the pores of the porous carbon. The reaction lasts for 6 to 8 hours. The resulting waste gas is discharged via pipeline 102 to the silane waste gas treatment pipeline. When the material accumulates at the bottom of the fluidized bed, valve a2 is opened, and the gas in pipeline 103 is used to purge the material into storage tank A2. Valve a2 is then closed. Next, inert gas is introduced via pipeline 105, sweeping the material from storage tank A2 into cyclone separator A3. After separation in cyclone separator A3, the waste gas enters the silane waste gas treatment pipeline via pipeline 107, and the material enters storage tank A4 via pipeline 108. Subsequently, inert gas is introduced through pipeline 109 to purge the material from storage tank A4 into fluidized bed B1. Simultaneously, a mixture of hydrocarbon gas and inert gas is introduced through pipeline 203. Fluidized bed B1 operates within a temperature range of 550°C to 650°C, preferably 600°C. The hydrocarbon gas decomposes at high temperatures to produce carbon, which coats the surface of the material. The reaction lasts for 2 to 4 hours. The resulting waste gas is discharged through pipeline 202 to the hydrocarbon waste gas treatment pipeline. When the material accumulates at the bottom of the fluidized bed, valve b2 is opened, and the gas from pipeline 203 is used to purge the material into storage tank B2. Valve b2 is then closed. Next, inert gas is introduced through pipeline 205 to purge the material from storage tank B2 into cyclone separator B3. After separation in cyclone separator B3, the waste gas enters the hydrocarbon waste gas treatment pipeline through pipeline 207, and the material enters storage tank B4 through pipeline 208. Finally, inert gas is introduced through pipeline 209 to purge the material from storage tank B4 into heat exchanger C1. A coolant (such as cooling water or Freon) is introduced through pipeline 301 to cool the material. The cooled material then flows through pipeline 302 into cyclone separator C2. After separation, the waste gas is discharged through pipeline 305, and the material is output through pipeline 306, completing the preparation of the silicon-carbon anode material.

[0025] In the above process, the multi-stage variable diameter design of fluidized bed A1 and fluidized bed B1 plays a key role. As the internal diameter of the fluidized bed gradually decreases from top to bottom, the gas flow rate also increases accordingly, thus adapting to the characteristic that the material density gradually increases with the reaction process. This design not only expands the adaptability range of porous carbon flow rate, but also improves the stability of the material in the fluidized bed, avoiding blockage or deposition caused by flow rate mismatch. In addition, the gas distribution plate (structure such as Figure 3 (As shown in the figure, a1 and b1 are located in a constant-diameter zone at the bottom of the fluidized bed.) Their function is to evenly distribute the airflow from the bottom, ensuring a uniform flow field within the fluidized bed and sufficient contact between the material and the reaction gas. This design significantly improves reaction efficiency and ensures product uniformity.

[0026] The continuous production method of the present invention reduces the need for frequent heating and cooling of equipment, significantly extending the service life of key components. For example, in the traditional single-stage fluidized bed design, the equipment needs to be frequently heated and cooled to adapt to the reaction conditions at different stages, which not only increases energy consumption but also accelerates equipment aging. In the present invention, through the design of a multi-stage variable diameter fluidized bed and a continuous process flow, the reaction conditions at each stage can be stably maintained, thereby greatly reducing equipment losses. In addition, the entire production process realizes the continuous preparation of silicon-carbon negative electrode materials, greatly improving production efficiency and reducing costs.

[0027] In order to verify the technical effects of the present invention, multiple example experiments were carried out.

[0028] Example 1 When in use, the porous carbon is first purged into the fluidized bed A1 along the pipeline 101 using nitrogen. The temperature of the fluidized bed A1 is 560°C and the specific surface area of ​​the porous carbon is 1800 m 2 / g, pore volume 0.8 cm 3 / g, silane and nitrogen are introduced into pipeline 103, the flow ratio of silane to nitrogen is 1:6, silane reacts at 560°C, the reaction time is 6 hours, and the reaction formula is: SiH4→Si+2H2 During the reaction, the silicon produced by the reaction is embedded in the pore structure of the porous carbon, causing the material density to continuously increase and the material to continuously sink to the bottom of fluidized bed A1. At regular intervals, valve a2 is opened, and the gas in pipeline 103 is used to purge the material along pipeline 104 into storage tank A2. Then, nitrogen gas blown from pipeline 105 is used to purge the material in storage tank A2 along pipeline 106 into cyclone separator A3. After separation in cyclone separator A3, the silane waste gas enters the silane waste gas treatment pipeline along pipeline 107, and the material enters storage tank A4 along pipeline 108. Nitrogen gas blown from pipeline 109 is used to purge the material in storage tank A4 along pipeline 201 into fluidized bed B1. In fluidized bed B1, acetylene and nitrogen are introduced into pipeline 203, with a flow ratio of acetylene to nitrogen of 1:3.5. The acetylene reacts at 600°C for 3 hours. The reaction formula is: C2H2→2C+2H2 During the reaction, the carbon produced by the reaction coats the surface of the material, causing the material density to continuously increase and the material to continuously sink to the bottom of the fluidized bed B1. At regular intervals, valve b2 is opened, and the gas in pipeline 203 is used to purge the material along pipeline 204 into storage tank B2. Then, nitrogen gas blown from pipeline 205 is used to purge the material in storage tank B2 along pipeline 206 into cyclone separator B3. After separation in cyclone separator B3, the acetylene waste gas enters the hydrocarbon waste gas treatment pipeline along pipeline 207, and the material enters storage tank B4 along pipeline 208. Nitrogen gas blown from pipeline 209 is used to purge the material in storage tank B4 along pipeline 304 into heat exchanger C1. Under the action of cooling water introduced into pipeline 301, the material is cooled and enters cyclone separator C2 along pipeline 302. After separation in cyclone separator C2, the waste gas is discharged along pipeline 305 and the material is discharged along pipeline 306.

[0029] Example 2 The difference from Example 1 is that the temperature of fluidized bed A1 is 580°C, and the rest is the same as Example 1.

[0030] Example 3 Different from Example 1, the flow ratio of silane to nitrogen is 1:8, and the rest is the same as Example 1.

[0031] Example 4 Different from Example 1, the flow ratio of silane to nitrogen is 1:4, and the rest is the same as Example 1.

[0032] The silicon-carbon negative electrode materials obtained in Examples 1 to 4 were used to prepare negative electrode sheets. The data obtained by using these negative electrode sheets to make lithium-ion batteries (button-type half-cells) are summarized in Table 1. Figure 4 This is the first charge and discharge curve of the silicon-carbon negative electrode material in Example 1. Figure 5 This is a coulombic efficiency performance diagram of the silicon-carbon negative electrode material in Example 1 after multiple cycles. The above data and pictures can be concluded that the lithium-ion batteries prepared by these samples produced by the device and method of the present invention have high capacity, high coulombic efficiency, stable cycle and good electrochemical performance.

[0033] Table 1 Test results of element content of silicon-carbon negative electrode materials prepared in Examples 1-4 First charge capacity (mAh / g) First discharge capacity (mAh / g) First coulombic efficiency (%) Example 1 1859.87 2052.82 90.60 Example 2 1830.00 2020.71 90.56 Example 3 1797.49 1988.30 90.40 Example 4 1912.34 2110.85 90.60 In summary, the present invention provides an efficient and stable silicon-carbon negative electrode material preparation solution through a multi-stage variable diameter fluidized bed design, a continuous production method and precise process control, which is suitable for industrial-scale production and has important economic and social value.

[0034] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the present invention may be implemented in other specific forms without departing from the spirit or essential characteristics of the present invention. Therefore, the embodiments should be considered in all respects as illustrative and non-restrictive, and the scope of the present invention is defined by the appended claims rather than the foregoing description. It is intended that all variations that fall within the meaning and range of equivalents of the claims be embraced within the present invention. Any reference sign in a claim should not be construed as limiting the claim to which it relates.

[0035] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any minor modifications, equivalent replacements, and improvements made to the above embodiments based on the technical essence of the present invention shall be included in the scope of protection of the technical solution of the present invention.

Claims

1. A continuous production device for silicon-carbon negative electrode materials, characterized by: The invention comprises at least two stages of fluidized bed reaction units connected in series, wherein the fluidized bed reaction units include a fluidized bed, a first storage tank, a cyclone separator and a second storage tank connected in sequence through pipelines. The material outlet of the fluidized bed reaction unit of the last stage is connected in sequence with the heat exchanger C1 and the cyclone separator C2 through pipelines. The fluidized bed adopts a multi-stage variable diameter design, and each stage includes a constant diameter area and a variable diameter area.

2. The continuous production device according to claim 1, characterized in that: The diameter of the constant diameter zone inside the fluidized bed decreases from top to bottom, and the diameter reduction ratio each time is between 10% and 25%.

3. The continuous production device according to claim 1 or 2, characterized in that: The angle α between the variable diameter zone of the fluidized bed and the vertical direction ranges from 30° to 60°.

4. The continuous production device according to claim 1 or 2, characterized in that: A gas distribution plate is installed in a constant diameter area at the bottom of the fluidized bed A1.

5. The continuous production device according to claim 1, characterized in that: The device is suitable for treating a specific surface area of ​​1600 m 2 / g~2000 m 2 / g, pore volume range is 0.7 cm 3 / g~0.9 cm 3 / g of porous carbon materials.

6. The continuous production device according to claim 1, characterized in that: The fluidized bed adopts a three-stage variable diameter design.

7. A method for producing silicon-carbon negative electrode materials using the continuous production device according to claim 1, characterized in that: The method comprises the following steps: (1) blowing the raw porous carbon along the pipeline with an inert gas and adding it into the fluidized bed A1 of the first-stage fluidized bed reaction unit, and simultaneously introducing a mixed gas of silane and inert gas into the fluidized bed A1 at a gas flow ratio of 1:(4-8), maintaining the fluidized bed temperature at 500-600°C, and reacting for 6-8 hours; (2) After the materials generated in the first-stage fluidized bed reaction unit are separated and treated, the solid material A is blown along the pipeline by inert gas into the fluidized bed B1 of the second-stage fluidized bed reaction unit. At the same time, a mixture of hydrocarbon gas and inert gas is introduced into the fluidized bed B1 at a gas flow ratio of 1: (2-5), and the fluidized bed temperature is maintained at 550-650°C for 2-4 hours. (3) The solid material B produced in the secondary fluidized bed reaction unit after separation treatment is blown along the pipeline by inert gas to the heat exchanger C1, and after cooling, the solid material C is separated to obtain the silicon-carbon negative electrode material.

8. A method for producing silicon-carbon negative electrode materials using the continuous production device according to claim 7, characterized in that: The inert gas is one or more of nitrogen, argon and helium.

9. A method for producing silicon-carbon negative electrode materials using the continuous production device according to claim 7, characterized in that: The heat exchanger C1 introduces a coolant through a pipeline to cool the material, and the coolant is one of cooling water and Freon.

10. A method for producing silicon-carbon negative electrode materials using the continuous production device according to claim 7, characterized in that: The specified temperature of the fluidized bed A1 is 560°C; the specified temperature of the fluidized bed B1 is 600°C.

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