CN117735530A - Preparation method and device for producing silicon-carbon anode material of lithium battery by two-stage reactor method - Google Patents
Preparation method and device for producing silicon-carbon anode material of lithium battery by two-stage reactor method Download PDFInfo
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/10—Energy storage using batteries
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Abstract
The invention relates to the technical field of nano material preparation, and discloses a preparation method for producing a silicon-carbon anode material of a lithium battery by using a two-stage reactor method, which comprises the following steps: s1, introducing a gaseous precursor of the nano-particles into a first-stage reaction area, and controlling the internal temperature to be 800-1000 DEG, and rapidly cracking the precursor into nano-scale small particles under the CVD reaction condition; s2, particles generated in the first-stage reaction area immediately enter a second-stage reaction cavity, the temperature inside the second-stage reaction cavity is controlled to be 800-1000 ℃, gaseous precursors of the nano particles are introduced into the first-stage reaction area, the precursors are rapidly cracked into nano-scale small particles under the CVD reaction condition, and simultaneously, precursors for carbon-containing coating are introduced into a second CVD reaction furnace, so that the precursors are heated and cracked into high-energy particles, and the high-energy particles are coated on the surfaces of the nano particles, so that the in-situ coating of the nano materials is realized. By setting the technological parameters of the first reaction equipment and the second reaction equipment, the nano material in-situ coating with the particle size below 100nm is realized.
Description
Technical Field
The invention relates to the technical field of nano material preparation, in particular to a preparation method and a device for producing a silicon-carbon anode material of a lithium battery by using a two-stage reactor method.
Background
In recent years, the preparation of nanoparticles and the study of their properties have attracted considerable attention. The nano particles have the characteristics of small-size effect, surface effect, quantum size effect, macroscopic quantum tunneling effect and the like, and show performances different from those of traditional materials, such as light, electricity, heat, magnetism, force and the like, so that the nano particles have important application in various fields of chemical industry, materials, electronics, machinery, environmental protection, biomedical engineering and the like.
The current methods for preparing nano particles mainly comprise a sol-gel method, an electrochemical method, a chemical precipitation method, a pyrolysis method, an ion implantation method, a plasma method, a self-assembly method, a template method and the like.
The sol-gel method can obtain a large amount of nano powder, has lower cost, is easy to agglomerate, and affects the actual application effect;
the purity, morphology and size of the nano particles prepared by the chemical precipitation method are difficult to control. The template method can obtain a large-area nanoparticle array, but the process is relatively complicated, and particularly the template is difficult to remove. The ion implantation method, the pyrolysis method, the plasma method, the electrochemistry method and the like require relatively complex experimental equipment and technological rules or higher temperature, so that the preparation cost of the nano particles is increased, and meanwhile, the practical application of the nano particles is influenced due to respective limitations. Therefore, a simple and controllable method has to be studied to obtain the nano-particles with high purity, good stability and controllable morphology and size distribution, and the preparation cost is reduced, so that the agglomeration of the nano-particles is avoided.
The silicon-carbon negative electrode material is mainly used for replacing a graphite negative electrode of a traditional lithium ion battery, so that the energy density of the battery can break through the bottleneck of the graphite negative electrode, and the performance can be greatly improved. The silicon-based anode material is considered as the anode material of the next generation of high-energy-density lithium ion battery with great potential because of the advantages of higher theoretical specific capacity (high temperature 4200mA.h/g, room temperature 3580mA.h/g), low lithium removal potential (< 0.5V), environmental friendliness, abundant reserves, lower cost and the like. The silicon-based anode material needs to solve the performance requirements of small particle size and good dispersibility of silicon particles, and can solve two important key problems in the large-scale use process:
(1) the silicon material repeatedly expands and contracts in the lithium intercalation process, so that the negative electrode material is pulverized and falls off, and finally the negative electrode material loses electrical contact, so that the battery is completely disabled;
(2) the continued growth of the SEI film on the surface of the silicon material can always irreversibly consume limited electrolyte in the battery and lithium from the positive electrode, ultimately resulting in rapid decay of the battery capacity.
In order to solve the above two problems, first, it is necessary to synthesize nanoscale silicon particles, for example, particles having a size of less than 150nm, which can effectively inhibit the expansion of materials, and reduce the problem of pulverization during repeated charge and discharge processes, thereby greatly prolonging the cycle stability of the battery. Although the nano material with the size of about 100nm can be obtained by using a high-energy ball milling method, the energy consumption is high, the particles have serious agglomeration phenomenon, so that a plurality of problems are brought to subsequent treatment, and the particles with the size of less than 50nm cannot be obtained;
second, the synthesized silicon nanomaterial requires the formation of an effective carbon coating on the surface to protect the silicon particles from direct contact reactions with the electrolyte while providing a carbon material with better electrical conductivity.
The invention provides a preparation method for producing a lithium battery silicon-carbon anode material by a two-stage reactor method, which can be used for preparing silicon particles with the grade of several nanometers to hundred nanometers, realizing online in-situ carbon coating, and generating a carbon protection layer by surface reaction with an introduced carbon precursor before the silicon particles leave a reaction area, thereby effectively protecting the silicon surface and improving the first coulomb efficiency of the silicon anode material during charging and discharging.
Disclosure of Invention
The invention aims to provide a preparation method for producing a silicon-carbon anode material of a lithium battery by using a two-stage reactor method, so as to solve the problems in the prior art.
In order to solve the technical problems, the invention provides the following technical scheme:
a preparation method for producing a silicon-carbon anode material of a lithium battery by using a two-stage reactor method comprises the following steps:
s1, introducing a gaseous precursor of the nano-particles into a first-stage reaction area, controlling the internal temperature to be 800-1000 degrees, and rapidly cracking the precursor into nano-scale small particles under the CVD reaction condition;
s2, particles generated in the first-stage reaction area enter the second-stage reaction cavity at the same time, and the internal temperature of the second-stage reaction cavity is controlled to be 800-1000 degrees;
s3, spraying a carbon-containing precursor into the second-stage reaction chamber through a carbon precursor nozzle in the second-stage reaction chamber, mixing the precursor with the first-stage particles, heating and cracking the mixture into high-energy particles by a second CVD (chemical vapor deposition) reaction furnace, and depositing the high-energy particles on the surfaces of silicon particles to form a membranous structure to obtain active nano particles coated with surface carbon;
s4, temporarily collecting the active nano particles in a collector;
and S5, finally discharging the active nano particles in the collector through a butterfly valve and finally storing the active nano particles for use.
Preferably, the gaseous precursor is a gaseous or liquid organic compound comprising the desired nanoparticle preparation, which organic compound is cleavable under CVD reaction conditions.
Preferably, the first stage and the second stage reactor are one or a combination of RTP reaction furnace, plasma reactor, microwave and intermediate frequency reaction device.
Preferably, the gaseous precursor is introduced and the shielding gas and the sensitization gas are introduced.
Preferably, the shielding gas is one or a mixture of N2, he, ar or H2, and the reaction gas is limited near the central position of the reaction cavity, so that the reaction gas is prevented from accumulating at the corners of other parts of the reactor.
Preferably, the pressure in the reaction chamber is less than 700torr.
The device for realizing the preparation method of the silicon-carbon anode material of the lithium battery by utilizing the two-stage reactor method comprises a reaction cavity, wherein a first reaction device and a second reaction device are sequentially arranged in the reaction cavity according to the reaction, a coating nozzle is arranged on the side surface of a channel of the reaction cavity, and the coating nozzle extends to the interior of the second reaction device;
the tail of the reaction cavity channel is communicated with a collecting chamber, an inclination condensing device is arranged in the collecting chamber, a particle collecting device is arranged below the condensing device, a finished product collecting vessel is arranged at the tail of the collecting chamber to collect finished products, and a butterfly valve is arranged between the collecting chamber and the finished product collecting vessel.
Preferably, the first reaction device and the second reaction device are one or a combination of an RTP reaction furnace, a plasma reactor, a microwave and an intermediate frequency reaction device.
Preferably, the coating nozzle comprises a nozzle body, and a plurality of tiny diffusion holes are formed in the outer surface of the nozzle body extending to the position of the second reaction equipment.
Preferably, the condensing device comprises a condensing plate filled with condensed water, a cleaning scraping plate driven by power to reciprocate is arranged on the condensing plate, the condensing plate divides a channel at the top of the collecting chamber into an inverted V shape, and the bottom of the diffusion hole is attached to the outer surface of the nozzle body.
Compared with the prior art, the invention has the following beneficial effects:
according to the invention, by arranging the first reaction equipment and the second reaction equipment, when the nano material is prepared, the gaseous precursor of the nano particles is introduced into the first-stage reaction area, the precursor is rapidly cracked into nano small particles under the CVD reaction condition, and the nano particles are heated and cracked into high-energy particles in the second CVD reaction furnace, so that the diameter of the prepared nano particles is in the range of 50-800nm, and the aim that the nano material is smaller than 100nm is fulfilled.
In the second, the two-stage nano material synthesis device of the invention, when the material enters the second reaction equipment, the coating substance is sprayed into the second reaction equipment through the coating nozzle, so that on-line in-situ carbon coating can be realized, and before the silicon particles leave the reaction area, the surface reaction with the introduced carbon precursor is carried out to generate a carbon protection layer, thereby effectively protecting the silicon surface and improving the first coulomb efficiency of the silicon anode material during charging and discharging;
secondly, because the vacuum degree requirement in the preparation process is lower, the production cost is greatly reduced, the equipment is simple, the process stability is good, the prepared nano particles are higher in purity, good in stability, uniform in morphology and particle size, and high in product quality reliability, meanwhile, the yield of the nano particles can be higher, and the two-stage precursor injection device can perform surface carbon coating in situ after nano-grade particles are prepared, so that the effect of reducing the preparation cost is achieved.
Drawings
FIG. 1 is a schematic diagram of the structure of the present invention;
FIG. 2 is a schematic view of a coating nozzle according to the present invention;
FIG. 3 is a schematic view of a condensing unit according to the present invention;
FIG. 4 is a scanning electron micrograph of a silicon carbon negative electrode material of the present invention;
FIG. 5 is a photograph of XRD diffraction patterns of a silicon-carbon negative electrode material of the present invention;
FIG. 6 is a charge-discharge diagram of a silicon-carbon negative electrode material of the present invention;
fig. 7 is a charge-discharge diagram of a commercial graphite anode material.
Wherein: 1. a reaction chamber channel; 2. a first reaction device; 3. a second reaction device; 4. coating the nozzle; 401. a nozzle body; 402. diffusion holes; 5. a collection chamber; 6. a condensing device; 601. a condensing plate; 602. cleaning a scraping plate; 7. a particulate filtration system; 8. a finished product collecting vessel; 9. butterfly valve.
Detailed Description
The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
Detailed description of the preferred embodiments
The embodiment is an embodiment of a preparation method for producing a silicon-carbon anode material of a lithium battery by using a two-stage reactor method.
A two-stage process for preparing nanoparticles features that the gaseous precursor of nanoparticles is introduced to the first-stage reaction region and the precursor is quickly cracked under the condition of CVD reaction to become nanoparticles. Particles generated in the first-stage reaction area immediately enter the second-stage reaction cavity; and a carbon precursor nozzle is arranged in the second-stage reaction cavity, after the precursor is mixed with the first-stage particles, the precursor is heated and cracked into high-energy particles by a second CVD reaction furnace, and a membranous structure is deposited on the surface of the silicon particles to obtain the active nano particles coated with surface carbon. The nanoparticles are collected by a collector.
Wherein the gaseous precursor is a gaseous or liquid organic compound comprising the desired preparation of the nanoparticle, which compound is cleavable under CVD reaction conditions. Generally, compounds that can be used in MOCVD can be used as precursors for the process.
Wherein, the temperature in the reaction cavity is controlled by adjusting RTP thermal power, and the temperature is controlled to be 800-1000 degrees.
The first stage and the second stage reactors can be RTP reaction furnaces, plasma reactors such as ICP plasma devices, microwave and intermediate frequency reaction devices and the like.
In addition, various gases such as shielding gas, sensitization gas and the like should be introduced at the same time of introducing the gaseous precursor. The protective gas is preferably N2 (ultra-blunt grade), and may be He, ar, H2, or the like, or a mixture thereof; he and H2 confine the reactant gases near the center of the reaction chamber, preventing them from building up at the corners of the other parts of the reactor. H2 also increases the temperature at which particles nucleate, preventing particle agglomeration.
Wherein, the pressure in the reaction cavity is less than 700torr;
the prepared active nano-particles are temporarily collected in a collector, and the active nano-particles in the collector are discharged through a butterfly valve 9 to be finally stored for use.
The nanoparticle preparation method of the present invention will be described by taking the preparation of silicon nanoparticles as an example.
Preparation of silicon nanoparticles starting from organic precursors of silicon such as silanes, for example but not limited to: siH4, si2H6, si3H8, and the like; chlorosilanes such as SiH2Cl2, siHCl3, siCl4, si2Cl6, and the like. The carbon precursor takes a carbon-containing gas precursor as a raw material, such as CH4; ethylene, acetylene, propane, propylene, and the like.
The organic precursor gas of silicon enters the first-stage reaction cavity through the gas inlet device, nano particles are generated after cracking reaction, then the nano particles enter the second-stage reactor and are mixed with the carbon precursor sprayed out of the nozzle, and the mixture enters the reaction area. In the first stage reaction cavity, heating organic silicon by an RTP furnace to crack, and generating silicon nano particles;
in the second-stage reaction cavity, the second-stage RTP furnace is used for heating, the carbon precursor is cracked, the carbon coating film is deposited on the surface of the silicon nano-particles, and the carbon-coated silicon particles are collected by a collecting device below the reaction cavity. The pressure in the reaction cavity is less than 700torr, and the diameter of the prepared silicon nano-particles is about 50-800nm.
Detailed description of the preferred embodiments
The embodiment is an embodiment of a device for realizing a preparation method for producing a silicon-carbon anode material of a lithium battery by using a two-stage reactor method.
Referring to fig. 1-7, a device for implementing a method for producing a silicon-carbon anode material of a lithium battery by using a two-stage reactor method comprises a reaction cavity channel 1, wherein the reaction cavity channel 1 is a circular channel, a first reaction device 2 and a second reaction device 3 are sequentially arranged on the reaction cavity 1 according to reaction, the first reaction device 2 and the second reaction device 3 are one or a combination of an RTP reaction furnace, a plasma reactor, microwaves and an intermediate frequency reaction device, a coating nozzle 4 is arranged on the side surface of the reaction cavity channel 1, and the coating nozzle 4 extends to the inside of the second reaction device 3;
the tail part of the reaction cavity channel 1 is communicated with a collecting chamber 5, an oblique angle condensing device 6 is arranged in the collecting chamber 5 and used for cooling particles and gas, a particle filtering system 7 is arranged below the condensing device 6, the particle filtering system 7 is a circular cloth bag collector, particles carried by the gas are attached to the outer surface of the particle filtering system 7 in the process of vacuumizing the interior of the collecting chamber 5, a rotatable brush is arranged on the surface of the particle filtering system 7 and used for brushing sediment attached to the surface of the cloth bag collector to the inner bottom part of the collecting chamber 5, a finished product collecting vessel 8 is arranged at the tail part of the collecting chamber 5 and used for collecting finished products, and a butterfly valve 9 is arranged between the collecting chamber 5 and the finished product collecting vessel 8;
all the air inlet and outlet pipe openings are provided with valves which are independently controlled and used for on-off control.
The main principle of conventional CVD pyrolysis is to use a reactant to decompose the reactant to form tiny particles under CVD conditions by rapid temperature rise, and rapidly leave a reaction zone to obtain nanoparticles. However, the pyrolysis method has the defects of serious agglomeration of the generated particles due to high reaction temperature and long reaction time, and the generated particles generally need to be further coated with carbon off-line and cannot be subjected to in-situ coating treatment. In the subsequent off-line treatment process, surface protection of a single particle layer cannot be formed, and coating protection is usually formed on the surface of the agglomerate, so that the advantages of the nano material cannot be exerted. The device cracks the material into high-energy particles through two-stage reaction so as to prepare the small-particle nano material, and the vacuum degree requirement in the preparation process is low, so that the equipment cost is greatly reduced, the equipment is simple, the process stability is good, the prepared nano particles are high in purity, good in stability, uniform in morphology and particle size, high in product quality reliability and high in product quality reliability, and meanwhile, the two-stage precursor injection device can perform surface carbon coating in situ after preparing nano-scale particles, so that the effect of reducing the preparation cost is achieved.
According to the technical scheme, the first reaction equipment 2 and the second reaction equipment 3 are arranged, when nano materials are prepared, gaseous precursors of nano particles are introduced into the first-stage reaction area, the precursors are rapidly cracked into nano-scale small particles under the CVD reaction condition, and in the process that the materials enter the second reaction equipment 3, coating substances are sprayed into the second reaction equipment 3 through the coating nozzle 4, so that online in-situ carbon coating can be realized, and before the silicon particles leave the reaction area, the silicon particles react with the introduced carbon precursors on the surface to generate a carbon protection layer, so that the silicon surface is effectively protected, and the first coulomb efficiency of the silicon cathode material in charge and discharge is improved.
Specifically, the coating nozzle 4 includes a nozzle body 401 for delivering a carbon precursor mixture, a plurality of fine diffusion holes 402 are formed in the outer surface of the nozzle body 401 extending to the position of the second reaction device 3, the carbon precursor mixture is rapidly diffused in a large area inside the second reaction device 3 through the fine diffusion holes 402, and the carbon precursor is cracked under the action of high temperature inside the second reaction device 3, so that a carbon coating film is deposited on the surface of the silicon nanoparticles.
Specifically, condensing equipment 6 includes that the inside is annotated the condensate water condensation plate 601, the granule is cooled down and is subsided on the surface of condensation plate 601 or drop the bottom to collecting chamber 5 through the peripheral clearance of condensation plate 601 under the effect of condensation plate 601, be provided with by power drive reciprocating motion's clearance scraper blade 602 on the condensation plate 601, the clearance scraper blade 602 of setting is used for scraping the granule that the surface of condensation plate 601 was piled up to the interior bottom of collecting chamber 5, condensation plate 601 cuts apart collecting chamber 5 top passageway for the font of falling the V, reduce the direct surface of adhering to at particle filtration system 7's circular sack collector of granule, guarantee the stability of vacuum, the bottom of diffusion hole 402 is laminated with the surface of nozzle body 401.
The nano material prepared by the device is observed in microscopic morphology by using a transmission electron microscope, and the granularity of the material is about 10nm, the particle size distribution is uniform, and the particles are spherical and have good dispersion performance.
As shown in XRD diffraction pattern 5 obtained by using an X-ray diffraction analyzer (D8 ADVANCE type), a remarkable silicon diffraction front was found by the pattern, and the crystallinity was excellent.
The carbon content of the silicon carbon material was analyzed by using a carbon-sulfur analyzer, and the test data thereof are shown in table 1. And (5) testing coulombic efficiency for the first time. According to the mass ratio of 80:9:1:10, silicon carbon negative electrode material powder: SP (carbon black): CNT (carbon nanotubes): PAA (polyacrylic acid) is mixed, a proper amount of deionized water is added as a solvent, and the mixture is continuously stirred to be pasty by a magnetic stirrer. Pouring the stirred slurry on a copper foil with the thickness of 8 mu m, coating by an experimental coater, and drying for 3 hours under the vacuum condition at 90 ℃ to obtain the negative electrode plate. The electrode sheet was rolled to 150 μm on a manual pair roller machine, and then a round sheet with a diameter of 14mm was manufactured by a sheet punching machine, and the weight of the active material was weighed and calculated. The CR2032 type button cell was assembled in a glove box with a metallic lithium sheet as the counter electrode, a polypropylene microporous membrane as the separator, and 1mol of LiPF6 solution (the solvent was Ethylene Carbonate (EC)/dimethyl carbonate (DMC), in a volume ratio of 1:1) as the electrolyte, to assemble the button cell.
And (3) performing constant-current charge and discharge testing by using a blue-electricity (LAND) battery testing system, wherein the discharge cut-off voltage is 0.005V, the charge cut-off voltage is 1.5V, and the charge and discharge testing is performed by using 0.1C current.
The commercial graphite negative electrode was used as comparative example 1, and the results of each example and comparative test are shown in table 1.
TABLE 1
Through the table 1, the silicon-carbon material has the specific charge capacity of 2600-2800mAh/g, which is 8 times of the specific charge capacity 345.2mAh/g of the traditional graphite cathode material, and has obvious capacity advantage. The specific capacity of the material decreases as the carbon content of the silicon-carbon material increases, which is mainly due to the low carbon content, which results in a decrease in the silicon-carbon capacity as the carbon content increases. Wherein the initial coulombic efficiency of the silicon-carbon material is increased from 81.2% to 86.7%. Compared with the traditional graphite anode material, the first coulombic efficiency of 92.0 percent is 5 percent. Meanwhile, for the silicon-carbon material with high carbon content, the high carbon content means that the coating is comprehensive, and the surface activity of the silicon material is reduced, so that the first coulombic efficiency is improved. By comparing the parameters of the carbon content, the specific charge capacity, the first coulombic efficiency and the like of the example 1 and the example 2 with those of the commercial graphite cathode in the proportion 1, the preparation of materials with different carbon contents can be realized in the silicon-carbon cathode material prepared by the two-stage reactor, and the specific charge capacity of the material is obviously improved.
Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made therein without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.
Claims (10)
1. A preparation method for producing a silicon-carbon anode material of a lithium battery by using a two-stage reactor method is characterized by comprising the following steps of: the method comprises the following steps:
s1, introducing a gaseous precursor of the nano-particles into a first-stage reaction area, and controlling the internal temperature to be 800-1000 DEG, and rapidly cracking the precursor into nano-scale small particles under the CVD reaction condition;
s2, particles generated in the first-stage reaction area enter the second-stage reaction cavity at the same time, and the internal temperature of the second-stage reaction cavity is controlled to be 800-1000 degrees;
s3, spraying a carbon-containing precursor into the second-stage reaction chamber through a carbon precursor nozzle in the second-stage reaction chamber, mixing the precursor with the first-stage particles, heating and cracking the mixture into high-energy particles by a second CVD (chemical vapor deposition) reaction furnace, and depositing the high-energy particles on the surfaces of the nano particles to form a membranous structure to obtain active nano particles coated with surface carbon;
s4, temporarily collecting the active nano particles in a collector;
and S5, finally discharging the active nano particles in the collector through a butterfly valve and finally storing the active nano particles for use.
2. The method for producing the silicon-carbon anode material of the lithium battery by using the two-stage reactor method according to claim 1, wherein the method comprises the following steps: the gaseous precursor is a gaseous or liquid organic compound comprising the desired preparation of the nanoparticles, which organic compound is cleavable under CVD reaction conditions.
3. The method for producing the silicon-carbon anode material of the lithium battery by using the two-stage reactor method according to claim 1, wherein the method comprises the following steps: the first stage reactor and the second stage reactor are one or a combination of RTP reactor, plasma reactor, microwave reactor and intermediate frequency reactor.
4. The method for producing the silicon-carbon anode material of the lithium battery by using the two-stage reactor method according to claim 1, wherein the method comprises the following steps: the protective gas and the sensitization gas are introduced while the gaseous precursor is introduced.
5. The method for producing the silicon-carbon anode material of the lithium battery by using the two-stage reactor method according to claim 4, which is characterized in that: the shielding gas is one or a mixture of N2, he, ar or H2, and the reaction gas is limited near the central position of the reaction cavity, so that the reaction gas is prevented from accumulating at the corners of other parts of the reactor.
6. The method for producing the silicon-carbon anode material of the lithium battery by using the two-stage reactor method according to claim 1, wherein the method comprises the following steps: the pressure in the reaction chamber is less than 700torr.
7. The device for realizing the preparation method of the silicon-carbon anode material of the lithium battery by utilizing the two-stage reactor method is characterized in that: the reaction device comprises a reaction cavity channel (1), wherein a first reaction device (2) and a second reaction device (3) are sequentially arranged on the reaction cavity channel (1) according to the reaction, a coating nozzle (4) is arranged on the side surface of the reaction cavity channel (1), and the coating nozzle (4) extends to the interior of the second reaction device (3);
the tail of reaction chamber passageway (1) is linked together and is had collection room (5), the internally mounted of collection room (5) has inclination condensing equipment (6), particle filtration system (7) are installed to the below of condensing equipment (6), and particle filtration system connects vacuum system afterwards, the afterbody of collection room (5) is provided with finished product collection household utensils (8) and collects the finished product, install butterfly valve (9) between collection room (5) and finished product collection household utensils (8).
8. The device for realizing the preparation method of the silicon-carbon anode material of the lithium battery by using the two-stage reactor method according to claim 7, wherein the device comprises the following components: the first reaction equipment (2) and the second reaction equipment (3) are one or a combination of an RTP reaction furnace, a plasma reactor, microwaves and an intermediate frequency reaction device.
9. The device for realizing the preparation method of the silicon-carbon anode material of the lithium battery by using the two-stage reactor method according to claim 7, wherein the device comprises the following components: the coating nozzle (4) comprises a nozzle body (401), and a plurality of tiny diffusion holes (402) are formed in the outer surface of the nozzle body (401) extending to the position of the second reaction equipment (3).
10. The device for realizing the preparation method of the silicon-carbon anode material of the lithium battery by utilizing the two-stage reactor method according to claim 9, which is characterized in that: the condensing device (6) comprises a condensing plate (601) filled with condensed water, a cleaning scraping plate (602) driven by power to reciprocate is arranged on the condensing plate (601), the condensing plate (601) divides a channel at the top of the collecting chamber (5) into an inverted V shape, and the bottom of the diffusion hole (402) is attached to the outer surface of the nozzle body (401).
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