Continuous production system for carbon-silicon negative electrode material
By setting up reactors in the silane deposition reactor group and the coated carbon deposition reactor group and adopting the reverse gas-material contact method, the problems of uneven fluidization state, uneven temperature and uneven silicon deposition in intermittent fluidized bed production are solved, and efficient continuous production of silicon-carbon negative electrode materials is achieved, thereby improving product quality and output.
Patent Information
- Application Number
- CN202422836014.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-20
- Publication Date
- 2025-09-19
- Estimated Expiration
- 2034-11-20
AI Technical Summary
In the existing technology, the intermittent fluidized bed production process is difficult to achieve large-scale production of silicon-carbon negative electrode materials. There are problems such as uneven fluidization state, uneven temperature, poor product consistency and uneven silicon deposition, resulting in low production efficiency and poor product quality.
A continuous production system for carbon-silicon negative electrode materials is adopted. By setting at least one reactor in the silane deposition reactor group and the coated carbon deposition reactor group, the gradual deposition of silicon and carbon is achieved. The reverse gas-material contact method is adopted to improve the contact uniformity between the gas and the material, thereby ensuring the uniformity of silicon and carbon deposition.
It achieves efficient fluidized-state reaction, improves silane conversion rate and silicon deposition uniformity, realizes continuous production of silicon-carbon negative electrode materials, improves product quality and output, and reduces production costs and raw material waste.
Smart Images
Figure CN223351648U_ABST
Abstract
Description
Technical Field
[0001] The present application relates to a continuous production system for carbon-silicon negative electrode materials, and belongs to the technical field of production and processing of carbon-silicon negative electrode materials. Background Art
[0002] In recent years, with the development of the new energy industry, lithium-ion battery anode materials have been rapidly evolving. Currently, the anode material used in large-scale commercial applications is graphite, which has a specific capacity of 365 mAh / g, very close to its theoretical specific capacity of only 372 mAh / g. Silicon-carbon anode materials, as a new generation of anode materials, address the high volume expansion problem of silicon anode materials and have become a hot topic of research.
[0003] However, how to scale up the production of high-quality silicon-carbon anode materials has become a major obstacle to their large-scale commercial application. The current mainstream process is an intermittent fluidized bed production process, with a commercial scale of 20kg / batch, meaning 10kg of output is completed in 10 hours. This involves first loading a certain amount of porous carbon into the reactor, followed by 5-8 hours of silicon precipitation and 2-3 hours of carbon precipitation, before pneumatically conveying the product to the feed tank. This intermittent production method is limited by the reactor's capacity, so to achieve large-scale production, the reactor diameter and height must be increased. However, it will bring new technical problems. First, it is necessary to match a higher gas volume. However, at present, a better fluidized state is mainly achieved through stirring, and it is difficult to achieve a good fluidized state under high gas volume; second, the increase in diameter will lead to uneven internal temperature, resulting in poor product quality and low conversion rate; third, due to the intermittent production method, the consistency of batch products prepared by larger diameter reactors (mainly specific capacity) will also decrease; fourth, when the fluidized bed gas flow in current commercial applications passes through the porous carbon bed, channeling is very likely to occur, which ultimately leads to uneven deposition of silicon in the porous carbon.
[0004] In order to solve the above technical problems, CN117599712A discloses a continuous production device for silicon-carbon negative electrode materials, which includes a deposition unit, a coating unit and a finished product tank. The deposition unit is provided with a deposition kettle, the coating unit is provided with a coating kettle, the porous carbon is fed in the middle of the deposition kettle, the silane gas is fed at the bottom of the deposition kettle to react to obtain a silicon-precipitated material, the silicon-precipitated material is fed at the bottom of the coating kettle, and the carbon source gas is fed at the bottom of the coating kettle to react to obtain a silicon-carbon negative electrode material. This setting causes uneven contact between the silicon-precipitated material and the carbon source gas in the carbon-precipitated reaction, and there are still problems such as uneven carbon precipitation reaction and decreased consistency of batch products. Utility Model Content
[0005] In order to solve the above problems, the present application proposes a continuous production system for carbon-silicon negative electrode materials. In this production system, at least one reactor is set in a silane deposition reactor group and a coated carbon deposition reactor group to realize the gradual deposition of silicon and carbon. In each silicon deposition reactor and each carbon deposition reactor, the gas enters at the bottom and the material enters at the top, thereby improving the contact uniformity between the gas and the material and realizing an efficient fluidized state. The synergistic effects of the above can not only improve the uniformity of silicon deposition and carbon deposition, but also improve the consistency of batch products.
[0006] The present application provides a continuous production system for carbon-silicon negative electrode materials, comprising: a storage tank, a silane deposition reactor group, a coated carbon deposition reactor group, and a finished product tank, which are sequentially connected in series;
[0007] The silane deposition reactor group includes at least one silicon deposition reactor, wherein the silicon deposition reactor is provided with a first feed port at the top, a first air inlet and a first discharge port at the bottom, and the first air inlet is used to introduce protective gas and silicon source gas;
[0008] The coated carbon deposition reactor group includes at least one carbon deposition reactor, wherein the upper portion of the carbon deposition reactor is provided with a second feed port, the lower portion is provided with a second air inlet and a second discharge port, and the second air inlet is used to introduce protective gas and carbon source gas;
[0009] The first feed port of the first silicon deposition reactor in the silane deposition reactor group is connected to the storage tank, the first discharge port of the last silicon deposition reactor is connected to the second feed port of the first carbon deposition reactor in the coated carbon deposition reactor group, and the second discharge port of the last carbon deposition reactor in the coated carbon deposition reactor group is connected to the finished product tank.
[0010] Optionally, there are at least two silicon deposition reactors.
[0011] Optionally, there are at least two carbon deposition reactors.
[0012] Optionally, a first baffle is provided in the silicon sinking reactor, and a first hydrogen outlet and a first protective gas outlet are provided on the silicon sinking reactor. The first hydrogen outlet is provided at the top of the silicon sinking reactor, and the first protective gas outlet is provided on the side wall of the silicon sinking reactor and is located above the first baffle.
[0013] Optionally, the gas flowing out of the first protective gas outlet of the first silicon deposition reactor in the silane deposition reactor group enters the next silicon deposition reactor in the silane deposition reactor group, and the gas flowing out of the first protective gas outlet of the last silicon deposition reactor in the silane deposition reactor group enters the first carbon deposition reactor in the coated carbon deposition reactor group.
[0014] Optionally, the width of the first baffle is 1 / 4 to 3 / 4 of the diameter of the silicon deposition reactor.
[0015] Optionally, a second baffle is provided in the carbon deposition reactor, and a second hydrogen outlet and a second protective gas outlet are provided on the silicon deposition reactor. The second hydrogen outlet is provided at the top of the silicon deposition reactor, and the second protective gas outlet is provided on the side wall of the silicon deposition reactor and is located above the second baffle.
[0016] Optionally, the gas flowing out of the second protective gas outlet of the first carbon deposition reactor in the coated carbon deposition reactor group enters the next carbon deposition reactor in the coated carbon deposition reactor group, and the second protective gas outlet of the last carbon deposition reactor in the coated carbon deposition reactor group is connected to the protective gas treatment device.
[0017] Optionally, the width of the second baffle is 1 / 4 to 3 / 4 of the diameter of the carbon deposition reactor.
[0018] Optionally, a first heating device is provided on the outside of the reaction cylinder of the silicon precipitation reactor;
[0019] A second heating device is provided outside the reaction cylinder of the carbon deposition reactor.
[0020] Optionally, a blowing mechanism is further included, and the blowing mechanism is connected to the silicon deposition reactor and the carbon deposition reactor respectively.
[0021] Optionally, a metering tank is provided between the storage tank and the silicon precipitation reactor group, and the metering tank is connected to the blowing mechanism.
[0022] The beneficial effects of this application include but are not limited to:
[0023] 1. The continuous production system of carbon-silicon negative electrode materials provided in this application carries out efficient fluidized state reaction in the reactor, which improves the silane conversion rate while also improving the uniformity of silicon deposition, realizing the continuous production of silicon-carbon negative electrode materials, and greatly improving the quality and output of silicon-carbon negative electrode materials.
[0024] 2. In the continuous production system of carbon-silicon negative electrode materials provided in this application, the solid raw materials and gases in the silicon deposition reactor and the carbon deposition reactor are in reverse contact, which can synergistically improve the silicon deposition uniformity, carbon deposition uniformity of the raw materials and the utilization rate of silicon source and carbon source gas.
[0025] 3. In the carbon-silicon negative electrode material continuous production system provided in the present application, the setting of the first baffle and the second baffle can realize the separation of hydrogen and protective gas, and can prevent the overflow of part of the porous carbon, thereby avoiding the waste of raw materials and reducing production costs.
[0026] 4. The carbon-silicon negative electrode material continuous production system provided in this application has a blowing mechanism that can realize the automatic transfer of materials, which not only improves the operational convenience of the production system, but also realizes gas replacement during the blowing process, ensuring that the environment in the reactor is consistent before each reaction, thereby improving the consistency of batch products. BRIEF DESCRIPTION OF THE DRAWINGS
[0027] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:
[0028] Figure 1 This is a schematic structural diagram of the continuous production system of carbon-silicon negative electrode materials involved in Example 1 of the present application;
[0029] Figure 2 This is a schematic structural diagram of the silicon deposition reactor involved in Example 1 of the present application;
[0030] Figure 3 This is a structural schematic diagram of the carbon deposition reactor involved in Example 1 of the present application.
[0031] List of parts and reference numerals:
[0032] 100, storage tank; 101, metering tank; 200, silicon deposition reactor; 201, first baffle; 202, first heating device; 203, first hydrogen outlet; 204, first shielding gas outlet; 300, carbon deposition reactor; 301, second baffle; 302, second heating device; 303, second hydrogen outlet; 304, second shielding gas outlet; 400, finished product tank; 500, blowing mechanism; 600, hydrogen treatment device; 601, shielding gas treatment device. Reference numerals 1-49 all refer to different valves. DETAILED DESCRIPTION
[0033] In order to more clearly illustrate the overall concept of the present application, a detailed description is given below in an illustrative manner in conjunction with the accompanying drawings.
[0034] In order to more clearly understand the above-mentioned objects, features and advantages of the present application, the present application is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that the embodiments of the present application and the features therein can be combined with each other in the absence of conflict.
[0035] In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application may also be implemented in other ways different from those described herein. Therefore, the scope of protection of the present application is not limited to the specific embodiments disclosed below.
[0036] In addition, in the description of the present application, it should be understood that the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "axial", "radial", "circumferential", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application.
[0037] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of such features. Throughout the description of this application, "plurality" means two or more, unless otherwise specifically defined.
[0038] In this application, unless otherwise expressly specified or limited, terms such as "installed," "connected," "connect," and "fixed" should be understood in a broad sense. For example, they may refer to fixed connection, detachable connection, or integration; mechanical connection, electrical connection, or communication; direct connection or indirect connection through an intermediate medium; and internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on specific circumstances.
[0039] In this application, unless otherwise expressly specified and limited, a first feature "above" or "below" a second feature may be that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in an appropriate manner in any one or more embodiments or examples.
[0040] refer to Figure 1-3, the embodiment of the present application discloses a continuous production system of carbon-silicon negative electrode materials, comprising: a storage tank 100, a silane deposition reactor group, a coated carbon deposition reactor group and a finished product tank 400 formed in series; the silane deposition reactor group comprises at least one silicon deposition reactor 200, the silicon deposition reactor 200 is provided with a first feed inlet at the top, a first air inlet and a first discharge port at the bottom, the first air inlet is used to introduce protective gas and silicon source gas; the coated carbon deposition reactor group comprises at least one carbon deposition reactor 300, the carbon deposition reactor A second feed port is provided at the upper part of the device 300, and a second air inlet and a second outlet are provided at the lower part. The second air inlet is used to introduce protective gas and carbon source gas; the first feed port of the first silicon deposition reactor 200 in the silane deposition reactor group is connected to the storage tank 100, and the first outlet port of the last silicon deposition reactor 200 is connected to the second feed port of the first carbon deposition reactor 300 in the coated carbon deposition reactor group, and the second outlet port of the last carbon deposition reactor 300 in the coated carbon deposition reactor group is connected to the finished product tank 400.
[0041] In the production system, at least one silicon deposition reactor 200 is provided in the silane deposition reactor group, and the silicon deposition reaction can be gradually carried out as needed. In each silicon deposition reactor 200, porous carbon enters through the first feed port, and silicon source gas and protective gas enter from the first gas inlet, which can realize the reverse contact of porous carbon and silicon source gas to obtain deposited silicon material. This setting is conducive to increasing the contact area between silicon source gas and porous carbon, improving silicon deposition uniformity, and reducing production costs and gas post-processing difficulty. Similarly, in the production system, at least one carbon deposition reactor 300 is provided in the coated carbon deposition reactor group, and the specific number of carbon deposition reactors 300 can also be set according to demand, and the deposited silicon material in each carbon deposition reactor 300 is also in reverse contact with the carbon source gas, thereby improving carbon deposition uniformity and the utilization rate of carbon source gas.
[0042] Through the above-mentioned settings, the production system can realize the continuous production of silicon-carbon negative electrode materials, and achieve efficient fluidization in the reactor, improve the conversion rate of silicon source gas and carbon source gas, obtain silicon-carbon negative electrode materials with good uniformity of silicon and carbon deposition, and improve the consistency of batch production products.
[0043] Specifically, during the operation of the production system, the reaction parameters and operating steps of each component can be set modularly, which can reduce manpower operations, save production costs and improve production efficiency.
[0044] Specifically, the protective gas may be at least one of nitrogen, argon, helium or other inert gases, preferably nitrogen.
[0045] Specifically, the silicon source gas may be at least one of monosilane, disilane, and trisilane.
[0046] As a specific embodiment, two silicon deposition reactors 200 are provided in the silane deposition reactor group, and one carbon deposition reactor 300 is provided in the coated carbon deposition reactor group, which is beneficial to improving the uniformity of silicon deposition and controlling the silicon deposition process to achieve continuous production.
[0047] As another specific embodiment, a silicon deposition reactor 200 is provided in the silane deposition reactor group, and two carbon deposition reactors 300 are provided in the coated carbon deposition reactor group, which is beneficial to improving the uniformity of carbon deposition and controlling the carbon deposition process to achieve continuous production.
[0048] As an embodiment, there are at least two silicon deposition reactors 200 and at least two carbon deposition reactors 300. The above configurations can improve the uniformity of silicon deposition and carbon deposition reactions and control the silicon deposition and carbon deposition reactions separately, further improving the consistency of batch production products.
[0049] As a specific embodiment, there are five silicon deposition reactors 200 and two carbon deposition reactors 300. Since the silicon deposition reaction time is longer than the carbon deposition reaction time, this configuration, with the silicon deposition reactors 200 and 300 having the same volume and a predetermined silicon deposition reaction time and carbon deposition reaction time, further subdivides the silicon deposition reaction compared to the carbon deposition reaction. This can gradually improve the uniformity of silicon deposition and the conversion rate of the silicon source gas, thereby reducing the silicon source gas content in the exhaust gas.
[0050] refer to Figure 2 As an embodiment, a first baffle 201 is provided in the silicon sinking reactor 200, and a first hydrogen outlet 203 and a first protective gas outlet 204 are provided on the silicon sinking reactor 200. The first hydrogen outlet 203 is provided at the top of the silicon sinking reactor 200, and the first protective gas outlet 204 is provided on the side wall of the silicon sinking reactor 200 and is located above the first baffle 201.
[0051] Hydrogen is produced during the silicon deposition reaction, and its density is lighter than that of the protective gas. The setting of the first baffle 201 can, on the one hand, intercept the hydrogen and the protective gas, promote the smooth progress of the reaction, and avoid direct outflow of the gas to cause waste of gas; on the other hand, it can block the overflow of part of the porous carbon to avoid waste of raw materials. The hydrogen can flow out along the first hydrogen outlet 203 at the top, and the nitrogen flows out along the side wall of the silicon deposition reactor 200, reducing the post-processing process of the gas.
[0052] A pressure relief valve may be provided at the first hydrogen outlet 203 , which automatically opens to discharge hydrogen when the pressure in the silicon deposition reactor 200 reaches a set value, thereby improving the operational convenience of the production system.
[0053] Specifically, the first protective gas outlet 204 can be directly connected to a gas recovery device, or it can be connected to the next reactor for continued use. Since the silicon source gas is not completely consumed in the reaction between the silicon source gas and the porous carbon, the gas discharged from the first protective gas outlet 204 still contains a small amount of silicon source gas. Therefore, connecting the gas discharged from the first protective gas outlet 204 to the next reactor for direct use can improve the utilization rate of the silane gas, realize the recycling of the protective gas, and save energy.
[0054] As an embodiment, the gas flowing out of the first protective gas outlet 204 in the silane deposition reactor group enters the next silicon deposition reactor 200 in the silane deposition reactor group, and the gas flowing out of the first protective gas outlet 204 of the last silicon deposition reactor 200 in the silane deposition reactor group enters the first carbon deposition reactor 300 in the coated carbon deposition reactor group.
[0055] refer to Figure 1-2 Assuming that nitrogen is used as the protective hydrogen, under this setting, process nitrogen can be introduced only into the first silicon sinking reactor 200 in the silicon sinking reactor 200 group. The hydrogen and nitrogen are separated at the top of the first silicon sinking reactor 200, and the separated nitrogen can be directly used in the second silicon sinking reactor 200, until the nitrogen in the first silicon sinking reactor 200 flows into the first carbon sinking reactor 300. Therefore, the recycling of nitrogen and trace silicon source gas can be achieved, saving production costs.
[0056] As an embodiment, the width of the first baffle 201 is 1 / 4 to 3 / 4 of the diameter of the silicon deposition reactor 200 .
[0057] The size of the first baffle 201 determines the gap size between the first baffle 201 and the silicon deposition reactor 200. If the size of the first baffle 201 is too large, the gap size is too small. At this time, it is not easy for the gas to pass through, which will cause the air pressure in the silicon deposition reactor 200 to increase, which is not conducive to safe production and will also affect the normal operation of the blowing mechanism 500. If the size of the first baffle 201 is too small, the gap size is too large, and there will still be a problem of incomplete gas separation and direct outflow.
[0058] The height of the first baffle 201 in the silicon deposition reactor 200 determines the degree of gas separation, and those skilled in the art can set it as needed, as long as it is located below the first protective gas outlet 204 .
[0059] refer to Figure 3As an embodiment, a second baffle 301 is provided in the carbon deposition reactor 300, and a second hydrogen outlet 303 and a second protective gas outlet 304 are provided on the silicon deposition reactor 200. The second hydrogen outlet 303 is provided at the top of the silicon deposition reactor 200, and the second protective gas outlet 304 is provided on the side wall of the silicon deposition reactor 200 and is located above the second baffle 301.
[0060] As an embodiment, the gas flowing out of the second protective gas outlet 304 of the first carbon deposition reactor 300 in the coated carbon deposition reactor group enters the next carbon deposition reactor 300 in the coated carbon deposition reactor group, and the second protective gas outlet 304 of the last carbon deposition reactor 300 in the coated carbon deposition reactor group is connected to the protective gas treatment device 601.
[0061] Based on the same design concept, a second baffle 301 is provided in the carbon deposition reactor 300 to promote the smooth progress of the reaction and separate the shielding gas from the hydrogen. The separated hydrogen can be combined with the hydrogen separated by the silicon deposition reactor 200 and flowed into the hydrogen processing device 600 for hydrogen recovery. The shielding gas can also be recycled. The second shielding outlet of the last silicon deposition reactor 200 is connected to the shielding gas processing device 601, which can also realize the recovery of nitrogen. The recovered nitrogen can be directly used for displacement or other process operations.
[0062] As an embodiment, the width of the second baffle 301 is 1 / 4 to 3 / 4 of the diameter of the carbon deposition reactor 300 .
[0063] As above, the size of the second baffle 301 determines the gap size between the second baffle 301 and the carbon deposition reactor 300. If the size of the second baffle 301 is too large, the gap size is too small. At this time, it is not easy for the gas to pass through, which will cause the air pressure in the carbon deposition reactor 300 to increase, which is not conducive to safe production. It will also affect the normal operation of the blowing mechanism 500. If the size of the second baffle 301 is too small, the gap size is too large, and there will still be a problem of incomplete gas separation and direct outflow.
[0064] The height of the second baffle 301 in the silicon deposition reactor 200 determines the degree of gas separation, and those skilled in the art can set it as needed, as long as it is located below the second protective gas outlet 304 .
[0065] As an embodiment, a first heating device 202 is provided outside the reaction cylinder of the silicon deposition reactor 200 , and a second heating device 302 is provided outside the reaction cylinder of the carbon deposition reactor 300 .
[0066] The first heating device 202 is located near the first air inlet, and the second heating device 302 is located near the second air inlet. The first heating device 202 and the second heating device 302 are set in the fluidization position. This setting is located at the bottom of the reactor for the silicon and carbon deposition reactions. After the reaction is sufficient, the gas is discharged from the bottom to the top of the next reactor, and then the silicon and carbon deposition reactions continue. This setting can improve the reaction efficiency of the silicon source gas, carbon source gas, and porous carbon, facilitate real-time control of the reaction temperature, improve the uniformity of silicon and carbon deposition, and further improve the consistency of batch products.
[0067] Specifically, since each silicon deposition reactor 200 and each carbon deposition reactor 300 uses a separate first heating device 202 or second heating device 302, the temperature of each silicon deposition reactor 200 and the temperature of each carbon deposition reactor 300 can be set separately during production according to actual needs. In this way, each silicon deposition reactor 200 and each carbon deposition reactor 300 can be controlled separately, thereby improving the operational flexibility of the production system.
[0068] As an embodiment, a metering tank 101 is installed between the storage tank 100 and the silicon precipitation reactor 200. The metering tank 101 and multiple reactors in this production system can be integrated into a single module, reducing the number of on-site operators and enabling automated operation and production. Therefore, the installation of the metering tank 101 enables precise control of material feeding, laying the foundation for automated production.
[0069] As an embodiment, a blowing mechanism 500 is further included, and the blowing mechanism 500 is respectively connected to the metering tank 101, the silicon deposition reactor 200 and the carbon deposition reactor 300.
[0070] The setting of the blowing mechanism 500 can realize the automatic transfer of materials, further improving the operational convenience of the production system. In addition, the blowing mechanism 500 uses gas for feeding, and the gas can be selected as a protective gas. Therefore, during the blowing process, not only the transfer of raw materials can be realized, but also the replacement of gases can be realized, ensuring that the environment in the reactor is consistent before each reaction, thereby improving the consistency of batch products, saving gas replacement time, and improving production efficiency.
[0071] Specifically, the first gas inlet is used to introduce the protective gas and silicon source gas. There can be one first gas inlet, in which case the protective gas and silicon source gas enter the silicon precipitation reactor 200 together. There can also be two or more first gas inlets, in which the protective gas and silicon source gas enter the silicon precipitation reactor 200 separately through different inlets. Similarly, there can be one second gas inlet, or two or more.
[0072] As a preferred embodiment, there are two first gas inlets, one for introducing protective gas and one for introducing silicon source gas; there are two second gas inlets, one for introducing protective gas and one for introducing carbon source gas.
[0073] refer to Figure 1 , describing the usage of this production system as follows:
[0074] In this production system, the silane deposition reactor group contains 5 silicon deposition reactors 200, and the coated carbon deposition reactor group contains 2 carbon deposition reactors 300. The reaction temperature of the silicon deposition reactor 200 is set to 400-600°C, preferably 500°C, and the reaction time is 0.2-1.5h, preferably 1h; the reaction temperature of the carbon deposition reactor 300 is set to 500-700°C, preferably 600°C, and the reaction time is 0.2-1.5h, preferably 1h.
[0075] (1) Open the valves connecting the silicon deposition reactor 200 and the carbon deposition reactor 300 to replace the air in the system with gas, specifically:
[0076] ①Open valves 48-19-21-23-25-27-29-31-33-16 to replace the air in the corresponding pipelines. After ventilation for a certain period of time, close the above valves;
[0077] ②Open valves 20-22-24-26-28-30-32-15 to replace the air in the corresponding pipelines. After ventilation for a certain period of time, close the above valves;
[0078] Open valves 1-2-3-4-5-6-7 and 8-9-10-11-12-13-14 at the same time, and close valves 1-2-3-4-5-6-7 after ventilation for a certain period of time;
[0079] Open valves 44-36-37-38-39-40-45-42-43 at the same time. After ventilation for a certain period of time, close all the valves in the open state.
[0080] ③ Open valve 46-16 to replace the air in the finished product tank 400;
[0081] ④ Repeat the above process once.
[0082] (2) Close valves 47 and 18, add 100 kg of porous carbon into the storage tank 100, open valve 17, and exhaust the air in the storage tank 100;
[0083] (3) Close valve 17, open valves 47 and 18, and deliver 2.5 kg of porous carbon in the storage bin into the metering tank 101 through a carrier gas such as nitrogen, and then deliver it into the first silicon precipitation reactor 200. After heating to 500° C., introduce silane gas and nitrogen in a ratio of 1:10, with a total volume flow rate of 10-50 L / min, and a reaction time of 0.2-1.5 h;
[0084] (4) After the reaction of the first silicon precipitation reactor 200 is completed, the air inlet valve is closed, the blowing mechanism 500 is opened, and the porous carbon is transported into the second silicon precipitation reactor 200. Then, 2.5 kg of fresh porous carbon is again transported into the first silicon precipitation reactor 200, the temperature is raised to 500° C., and the mixed gas is introduced to react for 0.2-1.5 hours;
[0085] (5) Similarly, after the reaction of the fifth silicon precipitation reactor 200 is completed, the porous carbon is sent to the first carbon precipitation reactor 300, the temperature is raised to 600°C, and a mixed gas (nitrogen and acetylene) is introduced, and the reaction time is 0.2-1.5h;
[0086] (6) After the reaction of the first carbon deposition reactor 300 is completed, the air inlet is closed, the blowing mechanism 500 is opened, and the porous carbon is transported into the second carbon deposition reactor 300. The temperature is raised to 600°C, and a mixed gas (nitrogen and acetylene) is introduced to react for 0.2-1.5 hours.
[0087] (7) After the reaction of the second carbon precipitation reactor 300 is completed, all air inlet valves are closed and the solid powder is sent to the next-level device in turn. For example, the solid powder of the silicon precipitation reactor 200 is sent to the finished product tank 400 for standby use. At this time, the solid powder of the first carbon precipitation reactor 300 is sent to the second carbon precipitation reactor 300, and so on.
[0088] This forms a semi-continuous reaction, with about 5 kg of product being delivered to the finished product tank 400 every hour. The material transfer time between the two reactors is about 1-5 minutes, thus forming a semi-continuous production process and improving the production efficiency of silicon-carbon negative electrode materials.
[0089] The various embodiments in this specification are described in a progressive manner. Similar parts between the various embodiments can be referred to in conjunction with each other. Each embodiment focuses on the differences between the other embodiments. In particular, the system embodiments are generally similar to the method embodiments, so the description is relatively simple. For relevant parts, refer to the description of the method embodiments.
[0090] The foregoing is merely an embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present application should all be included within the scope of the claims of the present application.
Claims
1. A continuous production system for carbon-silicon negative electrode materials, characterized in that: include: The storage tank, silane deposition reactor group, coated carbon deposition reactor group and finished product tank are sequentially connected in series; The silane deposition reactor group includes at least one silicon deposition reactor, wherein the silicon deposition reactor is provided with a first feed port at the top, a first air inlet and a first discharge port at the bottom, and the first air inlet is used to introduce protective gas and silicon source gas; The coated carbon deposition reactor group includes at least one carbon deposition reactor, wherein the upper portion of the carbon deposition reactor is provided with a second feed port, the lower portion is provided with a second air inlet and a second discharge port, and the second air inlet is used to introduce protective gas and carbon source gas; The first feed port of the first silicon deposition reactor in the silane deposition reactor group is connected to the storage tank, the first discharge port of the last silicon deposition reactor is connected to the second feed port of the first carbon deposition reactor in the coated carbon deposition reactor group, and the second discharge port of the last carbon deposition reactor in the coated carbon deposition reactor group is connected to the finished product tank.
2. The carbon-silicon negative electrode material continuous production system according to claim 1, characterized in that: There are at least two silicon precipitation reactors; and / or There are at least two carbon deposition reactors.
3. The carbon-silicon negative electrode material continuous production system according to claim 1, characterized in that: A first baffle is provided in the silicon sinking reactor, and a first hydrogen outlet and a first protective gas outlet are provided on the silicon sinking reactor. The first hydrogen outlet is provided on the top of the silicon sinking reactor, and the first protective gas outlet is provided on the side wall of the silicon sinking reactor and is located above the first baffle.
4. The carbon-silicon negative electrode material continuous production system according to claim 3, characterized in that: The gas flowing out of the first protective gas outlet of the first silicon deposition reactor in the silane deposition reactor group enters the next silicon deposition reactor in the silane deposition reactor group, and the gas flowing out of the first protective gas outlet of the last silicon deposition reactor in the silane deposition reactor group enters the first carbon deposition reactor in the coated carbon deposition reactor group.
5. The carbon-silicon negative electrode material continuous production system according to claim 3, characterized in that: The width of the first baffle is 1 / 4 to 3 / 4 of the diameter of the silicon deposition reactor.
6. The carbon-silicon negative electrode material continuous production system according to claim 1, characterized in that: A second baffle is provided in the carbon deposition reactor, and a second hydrogen outlet and a second protective gas outlet are provided on the silicon deposition reactor. The second hydrogen outlet is provided on the top of the silicon deposition reactor, and the second protective gas outlet is provided on the side wall of the silicon deposition reactor and is located above the second baffle.
7. The carbon-silicon negative electrode material continuous production system according to claim 6, characterized in that: The gas flowing out from the second protective gas outlet of the first carbon deposition reactor in the coated carbon deposition reactor group enters the next carbon deposition reactor in the coated carbon deposition reactor group, and the second protective gas outlet of the last carbon deposition reactor in the coated carbon deposition reactor group is connected to the protective gas treatment device.
8. The carbon-silicon negative electrode material continuous production system according to claim 6, characterized in that: The width of the second baffle is 1 / 4 to 3 / 4 of the diameter of the carbon deposition reactor.
9. The carbon-silicon negative electrode material continuous production system according to any one of claims 1 to 8, characterized in that: A first heating device is provided outside the reaction cylinder of the silicon precipitation reactor; A second heating device is provided outside the reaction cylinder of the carbon deposition reactor.
10. The carbon-silicon negative electrode material continuous production system according to any one of claims 1 to 8, characterized in that: It also includes a blowing mechanism, which is connected to the silicon deposition reactor and the carbon deposition reactor respectively.