A method and device for continuously preparing silicon-carbon negative electrode material based on a multi-stage gas-solid reactor

Abstract

The application discloses a kind of based on multistage gas-solid reactor's silicon-carbon negative electrode material continuous preparation method and equipment, the silicon-carbon negative electrode material continuous preparation method includes silicon coating and / or carbon coating;The silicon coating includes: step A1, silicon coating preheating;Step A2, silicon coating reaction;Step A3, silicon coating material separation;The carbon coating includes: step B1, carbon coating preheating;Step B2, carbon coating reaction;Step B3, carbon coating material separation;The silicon coating solid material is obtained after carbon coating the silicon-carbon negative electrode material, or, the carbon coating solid material is obtained after silicon coating the silicon-carbon negative electrode material.The silicon-carbon negative electrode material continuous preparation method of the application is simple and production process is continuous, suitable for industrialized production of silicon-carbon negative electrode material, can satisfy the demand of market to silicon-carbon negative electrode material.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of silicon-carbon negative electrode material preparation, in particular to a silicon-carbon negative electrode material continuous preparation method and device based on a multi-stage gas-solid reactor. BACKGROUND

[0002] Silicon-based negative electrode materials have become the most potential new generation of negative electrode materials to replace graphite negative electrode materials due to their high theoretical specific capacity (4200 mAh / g), abundant reserves, and environmental friendliness. However, compared with traditional graphite negative electrode materials, silicon-based materials have poor electrical conductivity, and silicon will undergo a huge volume expansion (>300%) during lithium extraction and insertion, which will cause silicon particles to be crushed, thereby seriously affecting the cycle performance and service life of the battery.

[0003] In order to solve the problem of volume expansion of silicon negative electrode materials during charging and discharging, which shortens the cycle performance of the battery, the current general research direction is silicon-carbon negative electrode materials. A preparation method for producing silicon-carbon negative electrode materials for lithium batteries using laser is disclosed in Chinese patent application CN117772098A. However, the device used in this method is complex, has high energy consumption, and has small production capacity, which makes it difficult to meet the requirements of large-scale production. Chinese invention patent application CN113957417A discloses a CVD fluidized deposition device. However, the production process of this device for silicon-carbon negative electrode materials is an intermittent process, which not only consumes a large amount of human and electrical resources, but also makes it difficult to realize industrialization and production, and cannot meet the market demand. Therefore, it is particularly important to find a silicon-carbon negative electrode material preparation method that can be industrialized. SUMMARY

[0004] The purpose of the present application is to provide a silicon-carbon negative electrode material continuous preparation method based on a multi-stage gas-solid reactor, which addresses the difficulty of industrialized production of silicon-carbon negative electrode materials in the prior art.

[0005] Another purpose of the present application is to provide a device based on the silicon-carbon negative electrode material continuous preparation method.

[0006] The technical solution adopted to achieve the purpose of the present application is as follows:

[0007] A silicon-carbon negative electrode material continuous preparation method based on a multi-stage gas-solid reactor, comprising silicon coating and / or carbon coating.

[0008] The silicon coating comprises the following steps:

[0009] Step A1, silicon coating preheating: the silicon coating substrate is preheated to a silicon coating preheating temperature and then enters a silicon coating gas-solid reactor, which contains a silicon source gas.

[0010] Step A2, silicon-coating reaction: the silicon-coated substrate after preheating is subjected to silicon-coating reaction with the silicon source gas in the silicon-coating gas-solid reactor to obtain the silicon-coated material;

[0011] Step A3, silicon-coated material separation: the silicon-coated material obtained in step A2 is subjected to silicon-coated material separation to obtain the silicon-coated solid material;

[0012] The carbon-coating includes the following steps:

[0013] Step B1, carbon-coating preheating: the carbon-coated substrate is preheated to a carbon-coating preheating temperature and then enters the carbon-coating gas-solid reactor containing the carbon source gas;

[0014] Step B2, carbon-coating reaction: the carbon-coated substrate after preheating is subjected to carbon-coating reaction with the carbon source gas in the carbon-coating gas-solid reactor to obtain the carbon-coated material;

[0015] Step B3, carbon-coated material separation: the carbon-coated material obtained in step B2 is subjected to carbon-coated material separation to obtain the carbon-coated solid material;

[0016] The silicon-coated solid material is subjected to carbon-coating to obtain the silicon-carbon negative electrode material, or the carbon-coated solid material is subjected to silicon-coating to obtain the silicon-carbon negative electrode material.

[0017] In the above technical solution, the silicon-coating gas-solid reactor includes at least one fluidized bed gas-solid reactor or rotary gas-solid reactor, and the carbon-coating gas-solid reactor includes at least one fluidized bed gas-solid reactor or rotary gas-solid reactor.

[0018] In the above technical solution, the silicon source gas is one or a mixture of several of silane, disilane, trisilane, tetrasilane, chlorosilane, tetramethoxysilane, tetramethylsilane, tetraethylsilane, tetraethoxysilane, triethenylmethoxysilane, triethenylethoxysilane, diethylenediethoxysilane, diethylenediethoxysilane, diethylenediethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, phenylsilane or diphenylsilane.

[0019] In the above technical solution, the carbon source gas is one or a mixture of several of pyrolytic carbon, monosaccharide, disaccharide, polysaccharide, sugar derivative, pitch, resin, aromatic hydrocarbon, alkane, olefin, alkyne.

[0020] In the above technical solution, the silicon-coated substrate is one or a mixture of several of elemental Si, SiO x , porous carbon, pyrolytic carbon, soft carbon, hard carbon, carbon black, graphite, carbon fiber, carbon nanotube, graphene, polysaccharide, sugar derivative, pitch, resin, aromatic hydrocarbon.

[0021] The carbon-coated substrate is one or a mixture of several of silicon-carbon materials with a melting point higher than 300℃, elemental Si, SiO x , porous carbon, pyrolytic carbon, soft carbon, hard carbon, carbon black, graphite, carbon fiber, carbon nanotube, graphene, polysaccharide, sugar derivative, pitch, resin, aromatic hydrocarbon;

[0022] The silicon-coated substrate and the carbon-coated substrate are pretreated before entering the gas-solid reactor to ensure that the substrate is free of air.

[0023] In the above technical solution, the silicon-coated preheating temperature is 300-900℃, the silicon-coated reaction temperature is 300-900℃, the pressure in the silicon-coated gas-solid reactor is less than 0.1 MPa positive pressure, and the residence time of the preheated silicon-coated substrate in the silicon-coated gas-solid reactor is 0.5-10 h.

[0024] The carbon-coated preheating temperature is 300-1200℃, the carbon-coated reaction temperature is 300-1200℃, the pressure in the carbon-coated gas-solid reactor is less than 0.1 MPa positive pressure, and the residence time of the preheated carbon-coated substrate in the carbon-coated gas-solid reactor is 0.5-10 h.

[0025] In another aspect of the present application, an apparatus based on the continuous preparation method of the silicon-carbon negative electrode material is provided, which at least includes two reaction modules connected by pipelines and an intermediate solid material conveyor;

[0026] One reaction module at least includes a preheater, a fluidized bed gas-solid reactor and a separator connected by pipelines, or at least includes a rotary gas-solid reactor, a solid material conveyor and a separator connected by pipelines, and the rotary gas-solid reactor includes a heating section and a reaction section.

[0027] In the above technical solution, the separator is one or a combination of several of electrostatic precipitator, bag-type dust collector, cyclone separator and inertial dust collector.

[0028] In the above technical solution, the tail end of the reaction module is further connected with a discharge solid material conveyor, and the feed inlet of the discharge solid material conveyor is connected to the discharge outlet of the separator.

[0029] In the above technical solution, when the reaction module includes a fluidized bed gas-solid reactor, the gas outlet of the separator is connected to the gas inlet of the fluidized bed gas-solid reactor; when the reaction module includes a rotary gas-solid reactor, the gas outlet of the separator is connected to the gas inlet of the rotary gas-solid reactor, and the gas outlet of the reaction section of the rotary gas-solid reactor is connected to the gas inlet of the heating section.

[0030] Compared with the prior art, the present application has the following advantages:

[0031] 1. The continuous preparation method of the silicon-carbon negative electrode material is simple and continuous, and is suitable for industrial production of the silicon-carbon negative electrode material, and can meet the market demand for the silicon-carbon negative electrode material.

[0032] 2. Compared with the existing intermittent production method, the method can maintain the operation of each gas-solid reactor under certain operating conditions, avoid the temperature rising and falling stages in the reaction process, and achieve the purposes of reducing energy consumption and shortening auxiliary operation time.

[0033] 3. The method combines the fluidized bed gas-solid reactor and the rotary gas-solid reactor, in the fluidized bed gas-solid reactor, the silicon layer or the carbon layer can be coated on the inside or surface of the substrate by adjusting the reaction conditions; in the rotary gas-solid reactor, the dense carbon layer or silicon layer can be coated, and through the combination of the fluidized bed gas-solid reactor and the rotary gas-solid reactor, the structure design and adjustment optimization of the silicon-carbon negative electrode material can be realized, so as to relieve the volume expansion of the silicon material and produce the silicon-carbon negative electrode material meeting the market demand.

[0034] 4. The carrier gas used in the coating process of the device is the gas produced by the cracking of the silicon source gas and the carbon source gas, which greatly saves the production cost. BRIEF DESCRIPTION OF DRAWINGS

[0035] Figure 1 The figure shows the process equipment diagram of the first continuous silicon-carbon negative electrode material equipment.

[0036] Figure 2 The figure shows the process equipment diagram of the second continuous silicon-carbon negative electrode material equipment.

[0037] Figure 3 The figure is the SEM diagram of the silicon-carbon negative electrode material prepared in Example 1 of the present application.

[0038] Figure 4 The figure is the Si distribution diagram in the silicon-carbon negative electrode material prepared in Example 1 of the present application.

[0039] Figure 5 The figure is the first charge-discharge curve diagram of the silicon-carbon negative electrode material prepared in Example 1 of the present application.

[0040] Figure 6 The figure is the electrochemical performance diagram of the silicon-carbon negative electrode material prepared in Example 1 of the present application after multiple cycles.

[0041] In the diagram: 101-First preheater, 102-First fluidized bed gas-solid reactor, 103-First separator, 104-First solid material conveyor, 105-First rotary gas-solid reactor, 106-First heating section, 107-First reaction section, 108-Second solid material conveyor, 109-Second separator, 110-Third solid material conveyor;

[0042] 201-Second preheater, 202-Second fluidized bed gas-solid reactor, 203-Third separator, 204-Fifth solid conveyor, 205-Second rotary gas-solid reactor, 206-Second heating section, 207-Second reaction section, 208-Sixth solid conveyor, 209-Fourth separator, 210-Seventh solid conveyor, 211-Fourth solid conveyor. Detailed Implementation

[0043] The present invention will be further described in detail below with reference to specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0044] Example 1

[0045] An apparatus based on the aforementioned continuous preparation method of silicon-carbon anode material includes two reaction modules, such as... Figure 1 As shown, the reactor includes a first preheater 101, a first fluidized bed gas-solid reactor 102, a first separator 103, a first solid material conveyor 104, a first rotary gas-solid reactor 105, a second solid material conveyor 108, a second separator 109, and a third solid material conveyor 110, which are connected in sequence by pipelines. The first rotary gas-solid reactor 105 includes a first heating section 106 and a first reaction section 107.

[0046] The gas outlet of the first separator 103 is connected to the gas inlet of the first fluidized bed gas-solid reactor 102, the gas outlet of the second separator 109 is connected to the gas inlet of the first rotary gas-solid reactor 105, and the gas outlet of the first reaction section 107 of the first rotary gas-solid reactor 105 is connected to the gas inlet of the first heating section 106.

[0047] Based on this, a continuous preparation method for silicon-carbon anode materials based on a multi-stage gas-solid reactor includes the following steps:

[0048] Step 1: The carbon fiber is preheated to 420°C by the first preheater 101 and then enters the first fluidized bed gas-solid reactor 102.

[0049] Step 2: The preheated carbon fiber and silane are reacted in the first fluidized bed gas-solid reactor 102 at 420°C and 0.02 MPa for 4 hours.

[0050] Step 3: The product obtained in step 2 enters a first separator 103, and after separation, the obtained solid material is used as the carbon-coated substrate and enters a first solid material conveyor 104, and the obtained gas returns to the inlet of the first fluidized bed gas-solid reactor 102 and is used as the carrier gas, forming a circulation structure;

[0051] Step 4: The first solid material conveyor 104 conveys the carbon-coated substrate to the first heating section 106 of the first rotary gas-solid reactor 105, and after preheating to 520℃, the carbon-coated substrate enters the first reaction section 107;

[0052] Step 5: The pitch gas is conveyed to the first reaction section 107 of the first rotary gas-solid reactor 105 through a gas path, and under the condition of 1200℃ and 0.02Mpa, the pitch gas reacts with the substrate for 3h;

[0053] Step 6: The second solid material conveyor 108 conveys the product obtained in step 5 to a second separator 109;

[0054] Step 7: The gas obtained after the end of the first rotary gas-solid reactor 105 and the second separator 109 is returned to the inlet of the first rotary gas-solid reactor 105 and is used as the carrier gas, forming a circulation structure;

[0055] Step 8: The solid obtained after the second separator 109 is separated is the silicon-carbon negative electrode material product.

[0056] The SEM and EDS images of the silicon-carbon negative electrode material prepared in the embodiment are shown in Figure 1 and Figure 2 From Table 1, Figure 1 and Figure 2 It can be seen that the continuous preparation method and device can make Si uniformly distributed on the C matrix, realize the full compounding of C and Si, and thus improve the specific capacity of the lithium ion battery.

[0057] Table 1: Element content test results of the silicon-carbon negative electrode material prepared in Example 1.

[0058] Element Line type wt % wt % Sigma At % C K line system 58.87 1.48 74.73 O K line system 7.19 0.71 6.85 Si K line system 33.94 1.20 18.42 Total amount 100.00 100.00

[0059] In summary Figure 3 and Figure 4 It can be seen that the first charge specific capacity of the lithium ion battery assembled by the silicon-carbon negative electrode material prepared in the embodiment is 1502.9mAh / g, the first discharge specific capacity is 1692.7mAh / g, the first coulombic efficiency is 88.79%, and the coulombic efficiency can be stably maintained at about 99% after 10 cycles.

[0060] Although the capacity is attenuated due to the volume expansion of Si, compared with the common graphite negative electrode in the market, the silicon-carbon negative electrode material provided by the technical scheme can greatly improve the capacity of the lithium ion battery. And the method adopts large-scale continuous production, which can fully meet the market demand for the yield of silicon-carbon negative electrode material.

[0061] Embodiment 2

[0062] An equipment based on the continuous preparation method of the silicon-carbon negative electrode material, comprising two reaction modules, such as Figure 1 As shown, comprising a first preheater 101, a first fluidized bed gas-solid reactor 102, a first separator 103, a first solid material conveyor 104, a first rotary gas-solid reactor 105, a second solid material conveyor 108, a second separator 109 and a third solid material conveyor 110 connected by pipelines in sequence, and the first rotary gas-solid reactor 105 comprises a first heating section 106 and a first reaction section 107.

[0063] The gas outlet of the first separator 103 is connected to the gas inlet of the first fluidized bed gas-solid reactor 102, the gas outlet of the second separator 109 is connected to the gas inlet of the first rotary gas-solid reactor 105, and the gas outlet of the first reaction section 107 of the first rotary gas-solid reactor 105 is connected to the gas inlet of the first heating section 106.

[0064] On this basis, a continuous preparation method of silicon-carbon negative electrode material based on a multi-stage gas-solid reactor, comprising the following steps:

[0065] Step 1, the silicon-carbon material is preheated to 500 DEG C. by the first preheater 101 and then enters the first fluidized bed gas-solid reactor 102;

[0066] Step 2, the preheated silicon-carbon material and the cracked carbon gas are reacted at 500 DEG C. and 0.01 Mpa for 5h in the first fluidized bed gas-solid reactor 102;

[0067] Step 3, the product obtained in step 2 enters the first separator 103, and after separation, the obtained solid material is used as a silicon-coated substrate and enters the first solid material conveyor 104, and the obtained gas after separation returns to the inlet of the first fluidized bed gas-solid reactor 102 and is used as a carrier gas, forming a circulation structure;

[0068] Step 4, the first solid material conveyor 104 conveys the silicon-coated substrate to the first heating section 106 of the first rotary gas-solid reactor 105, preheats to 550 DEG C. and then enters the first reaction section 107;

[0069] Step 5, the chlorosilane gas is conveyed to the first reaction section 107 by the gas path and reacts with the substrate at 550 DEG C. and 0.01 Mpa for 2h;

[0070] Step 6, the second solid material conveyor 108 conveys the product obtained in Step 5 to the second separator 109;

[0071] Step 7, the gas obtained after the end of the first rotary gas-solid reactor 105 and the second separator 109 is returned to the inlet of the first rotary gas-solid reactor 105 as a carrier gas, forming a circulation structure;

[0072] Step 8, the solid obtained after the separation of the second separator 109 is the silicon-carbon negative electrode material product.

[0073] Example 3

[0074] An apparatus based on the continuous preparation method of the silicon-carbon negative electrode material, comprising two reaction modules, as shown in Figure 2 The fourth solid material conveyor 211, the second rotary gas-solid reactor 205, the fifth solid material conveyor 204, the third separator 203, the sixth solid material conveyor 208, the second preheater 201, the second fluidized bed gas-solid reactor 202, the fourth separator 209 and the seventh solid material conveyor 210 are connected by pipelines in sequence, and the second rotary gas-solid reactor 205 comprises a second heating section 206 and a second reaction section 207.

[0075] The gas outlet of the third separator 203 is connected to the gas inlet of the second heating section 206, the gas outlet of the second reaction section 207 of the second rotary gas-solid reactor 205 is connected to the gas inlet of the second heating section 206, and the gas outlet of the fourth separator 209 is connected to the gas inlet of the second fluidized bed gas-solid reactor 202.

[0076] On this basis, a continuous preparation method of a silicon-carbon negative electrode material based on a multi-stage gas-solid reactor, comprising the following steps:

[0077] Step 1, the carbon black is conveyed by the fourth solid material conveyor 211 to the second heating section 206 of the second rotary gas-solid reactor 205, and after being preheated to 550°C, it enters the second reaction section 207;

[0078] Step 2, the vinyltrimethoxysilane is conveyed by a gas pipeline to the second reaction section 207, and reacts with the carbon black at 550°C and 0.03Mpa for 6h;

[0079] Step 3, the fifth solid material conveyor 204 conveys the product obtained in Step 2 to the third separator 203;

[0080] Step 4, the gas obtained after the end of the second rotary gas-solid reactor 205 and the third separator 203 is returned to the inlet of the second rotary gas-solid reactor 205 as a carrier gas, forming a circulation structure;

[0081] Step 5, the solid material obtained after the third separator 203 separates enters the second preheater 201 as the carbon-coated substrate;

[0082] Step 6, the carbon-coated substrate preheated to 600 DEG C by the second preheater 201 enters the second fluidized bed gas-solid reactor 202;

[0083] Step 7, the carbon-coated substrate and propylene gas are reacted in the second fluidized bed gas-solid reactor 202 at 600 DEG C and 0.03 MPa for 2 hours;

[0084] Step 8, the product obtained in step 7 enters the fourth separator 209, and the solid material obtained after separation is the silicon-carbon negative electrode material product.

[0085] Example 4

[0086] A continuous preparation method of silicon-carbon negative electrode material based on a multi-stage gas-solid reactor, the device of the embodiment includes a first reaction module, a second reaction module and a third reaction module, the first gas-solid reactor in the first reaction module is a fluidized bed gas-solid reactor, the second gas-solid reactor in the second reaction module is a rotary gas-solid reactor, and the third gas-solid reactor in the third reaction module is a fluidized bed gas-solid reactor, including the following steps:

[0087] Step 1, graphene is preheated to 480 DEG C by a preheater and then enters the first fluidized bed gas-solid reactor;

[0088] Step 2, the preheated graphene and triethenyl ethoxy silane are reacted in the first gas-solid reactor (fluidized bed gas-solid reactor) at 480 DEG C and 0.08 MPa for 2 hours;

[0089] Step 3, the product obtained in step 2 enters the first separator, and the solid material obtained after separation enters the first solid material conveyor as the carbon-coated substrate; the gas obtained after separation returns to the inlet of the fluidized bed gas-solid reactor and is used as carrier gas, forming a circulation structure;

[0090] Step 4, the first solid material conveyor delivers the carbon-coated substrate to the heating section of the second gas-solid reactor (rotary gas-solid reactor), which is preheated to 530 DEG C and then enters the reaction section;

[0091] Step 5, the resin gas is delivered to the reaction section through a gas path and reacts with the substrate at 530 DEG C and 0.08 MPa for 3 hours;

[0092] Step 6, the second solid material conveyor delivers the product obtained in step 5 to the second separator;

[0093] Step 7, the gas obtained after the end of the rotary gas-solid reactor and the second separator returns to the inlet of the second gas-solid reactor (rotary gas-solid reactor) and is used as carrier gas, forming a circulation structure;

[0094] Step 8, the carbon-coated substrate is preheated to 580℃ by a preheater and then enters a third gas-solid reactor (a fluidized bed gas-solid reactor);

[0095] Step 9, the carbon-coated substrate and acetylene gas are reacted in the third gas-solid reactor (a fluidized bed gas-solid reactor) at 580℃ and 0.08Mpa for 1h;

[0096] Step 10, the product obtained in step 11 enters a third separator, and the obtained solid material after separation is a silicon-carbon negative electrode material product.

[0097] The above only describes the preferred embodiments of the present application, and it should be noted that for those skilled in the art, some improvements and refinements can be made without departing from the principles of the present application, and these improvements and refinements should also be considered as the protection scope of the present application.

Claims

1. A method for continuous production of silicon-carbon anode material based on a multi-stage gas-solid reactor, characterized in that, comprising silicon coating and carbon coating; the silicon coating comprises the following steps: Step A1, silicon coating preheating: the silicon coating substrate is preheated to a silicon coating preheating temperature and then enters a silicon coating gas-solid reactor containing a silicon source gas; Step A2, silicon coating reaction: the preheated silicon coating substrate and the silicon source gas in the silicon coating gas-solid reactor are subjected to silicon coating reaction to obtain a silicon coated material; Step A3, silicon coating material separation: the silicon coated material obtained in Step A2 is subjected to silicon coating material separation to obtain a silicon coating solid material; the carbon coating comprises the following steps: Step B1, carbon coating preheating: the carbon coating substrate is preheated to a carbon coating preheating temperature and then enters a carbon coating gas-solid reactor containing a carbon source gas; Step B2, carbon coating reaction: the preheated carbon coating substrate and the carbon source gas in the carbon coating gas-solid reactor are subjected to carbon coating reaction to obtain a carbon coated material; Step B3, carbon coating material separation: the carbon coated material obtained in Step B2 is subjected to carbon coating material separation to obtain a carbon coating solid material; the silicon coating solid material is subjected to carbon coating to obtain the silicon-carbon negative electrode material, or the carbon coating solid material is subjected to silicon coating to obtain the silicon-carbon negative electrode material.

2. The continuous production method of a silicon-carbon negative material according to claim 1, wherein the silicon coating gas-solid reactor comprises at least one fluidized bed gas-solid reactor or rotary gas-solid reactor, and the carbon coating gas-solid reactor comprises at least one fluidized bed gas-solid reactor or rotary gas-solid reactor.

3. The continuous production method of the silicon-carbon negative material according to claim 1, wherein, the silicon source gas is a mixture of one or more of silane, disilane, trisilane, tetrasilane, chlorosilane, tetramethoxysilane, tetramethylsilane, tetraethylsilane, tetraethoxysilane, triethenylmethoxysilane, triethenylethoxysilane, diethylenediethoxysilane, diethylenediethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, phenylsilane or diphenylsilane.

4. The continuous production method of the silicon-carbon negative material according to claim 1, wherein, the carbon source gas is a mixture of one or more of cracked carbon, monosaccharide, disaccharide, polysaccharide, sugar derivative, pitch, resin, aromatic hydrocarbon, alkane, olefin, alkyne.

5. The continuous production method of the silicon-carbon negative material according to claim 1, wherein, The silicon-coated substrate is a mixture of one or more of Si, SiO x , porous carbon, pyrolytic carbon, soft carbon, hard carbon, carbon black, graphite, carbon fiber, carbon nanotube, graphene, polysaccharide, sugar derivative, pitch, resin, aromatic hydrocarbon The carbon-coated substrate is one or more of a mixture of silicon-carbon material with a melting point higher than 300°C, Si, SiO x , porous carbon, pyrolytic carbon, soft carbon, hard carbon, carbon black, graphite, carbon fiber, carbon nanotube, graphene, polysaccharide, sugar derivative, pitch, resin, aromatic hydrocarbon the silicon coating substrate and the carbon coating substrate are pretreated before entering the gas-solid reactor to ensure that the substrate is free of air.

6. The continuous production method of a silicon-carbon negative material according to claim 1, wherein the silicon coating preheating temperature is 300-900℃, the silicon coating reaction temperature is 300-900℃, the pressure in the silicon coating gas-solid reactor is less than 0.1 MPa, the residence time of the preheated silicon coating substrate in the silicon coating gas-solid reactor is 0.5-10 h; the carbon coating preheating temperature is 300-1200℃, the carbon coating reaction temperature is 300-1200℃, the pressure in the carbon coating gas-solid reactor is less than 0.1 MPa, and the residence time of the preheated carbon coating substrate in the carbon coating gas-solid reactor is 0.5-10 h.

7. An apparatus for continuous production of the silicon-carbon negative electrode material according to any one of claims 1 to 6, characterized in that, at least two reaction modules connected by pipelines and intermediate solid material conveyors; The reaction module comprises at least a preheater, a fluidized bed gas-solid reactor and a separator connected by pipelines, or at least a rotary gas-solid reactor, a solid material conveyor and a separator connected by pipelines, wherein the rotary gas-solid reactor comprises a heating section and a reaction section.

8. The apparatus of claim 7, wherein, The separator is a combination of one or more of an electrostatic precipitator, a bag filter, a cyclone separator and an inertial dust collector.

9. The apparatus of claim 7, wherein, The tail end of the reaction module is further connected with a discharge solid material conveyor, and the feeding port of the discharge solid material conveyor is connected to the discharge port of the separator.

10. The apparatus of claim 7, wherein, When the reaction module comprises a fluidized bed gas-solid reactor, the gas outlet of the separator is connected to the gas inlet of the fluidized bed gas-solid reactor; when the reaction module comprises a rotary gas-solid reactor, the gas outlet of the separator is connected to the gas inlet of the rotary gas-solid reactor, and the gas outlet of the reaction section of the rotary gas-solid reactor is connected to the gas inlet of the heating section.

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