Chemical vapor deposition device capable of correcting position of carbon raw material in deposition chamber
By introducing a moving sampler and guide rail into the chemical vapor deposition apparatus, the diffusion and pyrolysis time of the carbon source gas are controlled, solving the problem of low deposition efficiency in the production of hard carbon anodes and achieving high-efficiency deposition and performance improvement.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- 925 CARBON FOREVER TECH (TIANJIN) CO LTD
- Filing Date
- 2025-03-27
- Publication Date
- 2026-05-12
AI Technical Summary
In existing chemical vapor deposition methods for producing hard carbon anodes, the diffusion time and pyrolysis deposition time of the carbon source gas are mismatched, resulting in low deposition efficiency.
By setting a moving sampler and guide rail in the deposition chamber, and using a control system to monitor the rates of carrier gas and carbon source gas, the moving sampler is controlled to change the position of the reaction crucible, so that the diffusion time of the carbon source gas and the pyrolysis deposition time are matched.
It enables precise control of the carbon feedstock position in the deposition chamber, improves deposition efficiency, enhances the reversible capacity and low potential plateau capacity of the hard carbon anode, and improves the first coulombic efficiency.
Smart Images
Figure CN224227198U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of chemical vapor deposition technology, and in particular to a chemical vapor deposition apparatus that can correct the position of carbon raw materials in the deposition chamber. Background Technology
[0002] Renewable energy sources, such as wind and solar power, have developed rapidly in recent years, leading to a huge market demand for the energy storage industry. Among the many energy storage systems available, sodium-ion batteries are currently recognized by both academia and industry as the most promising electrochemical energy storage system due to their high energy conversion efficiency, abundant sodium resources, and low manufacturing costs.
[0003] Hard carbon materials are currently the most commercially available and promising anode materials for sodium-ion batteries. Unlike lithium-ion batteries, where the charge-discharge curve exhibits a ramp behavior dominated by ion adsorption, the porous structure of hard carbon in sodium-ion batteries provides conditions for the reversible and stable clustering of sodium ions, resulting in a significant low-potential plateau in the charge-discharge curve. This allows it to provide a higher output voltage as an anode in the overall battery system. Hard carbon prepared by chemical vapor deposition (CVD) using porous carbon with high specific surface area as a precursor often exhibits high sodium storage capacity due to its rich pore structure. However, current CVD methods for producing hard carbon anodes suffer from a mismatch between the diffusion time of the carbon source gas and the time required for cracking and deposition, resulting in low deposition efficiency. Utility Model Content
[0004] The purpose of this invention is to address the technical deficiencies in the existing technology by providing a chemical vapor deposition apparatus that can correct the position of carbon raw materials in the deposition chamber.
[0005] The technical solution adopted to achieve the purpose of this utility model is as follows:
[0006] A chemical vapor deposition apparatus capable of correcting the position of carbon feedstock within a deposition chamber includes a mass flow meter, a control system, a moving sampler, and a reaction crucible located within the deposition chamber. The moving sampler is mounted on the outer wall of the deposition chamber, and its actuating end is connected to the reaction crucible, which is used to hold the carbon feedstock. The moving sampler is connected to the control system, which is connected to the mass flow meter, which is installed at the external air inlet of the deposition chamber to monitor the rates of carrier gas and carbon source gas entering the deposition chamber. Based on the monitored rates, the control system controls the moving sampler to move, thereby changing the position of the reaction crucible relative to the air inlet of the deposition chamber.
[0007] In the above technical solution, a guide rail is provided in the deposition chamber, and a slider is installed on the reaction crucible. The slider is installed inside the guide rail, and the moving sampler drives the reaction crucible to move along the guide rail.
[0008] In the above technical solution, the actuating end of the moving sampler is connected to the reaction crucible via a sample injection rod.
[0009] In the above technical solution, the deposition chamber is a cylindrical cavity.
[0010] In the above technical solution, the injection rod is made of a high-temperature resistant material such as stainless steel, graphite or alumina.
[0011] In the above technical solution, the reaction crucible is made of a high-temperature resistant material such as stainless steel, graphite, or alumina.
[0012] In the above technical solutions, the sedimentation chamber is a sedimentation chamber of a fluidized bed, tubular furnace, rotary kiln, pusher kiln, roller kiln, conveyor belt kiln, air cushion kiln or walking beam furnace.
[0013] In the above technical solution, the distance L from the air inlet to the reaction crucible is V. 总 ×(3~10min), the V 总 The velocity v of the carrier gas 载 and the velocity v of the carbon source gas 碳 The sum of these values is expressed in cm / min.
[0014] In the above technical solution, the moving sampler is a ball screw.
[0015] In the above technical solution, the moving sampler is a spiral sampler controller.
[0016] Compared with the prior art, the beneficial effects of this utility model are:
[0017] The chemical vapor deposition apparatus of this invention can change the position of the carbon raw material in the deposition chamber by controlling the moving sampler, that is, change the position of the carbon raw material and the heating zone, so as to match the diffusion time of the carbon source gas with the time required for pyrolysis and deposition, thereby achieving efficient deposition. Attached Figure Description
[0018] Figure 1 This is a schematic diagram of the overall structure of the chemical vapor deposition apparatus of this utility model.
[0019] Figure 2 This is a schematic diagram of the overall structure of the chemical vapor deposition apparatus of this utility model.
[0020] Figure 3 This is a partial structural schematic diagram of the present invention.
[0021] Wherein: 1: mass flow meter, 2: guide rail, 3: moving injector, 4: injection rod, 5: reaction crucible, 6: deposition chamber, 7: heating zone, 8: slider, 9: control system. Detailed Implementation
[0022] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present invention and are not intended to limit the present invention.
[0023] Example 1
[0024] like Figure 1-3 As shown, a chemical vapor deposition apparatus capable of correcting the position of carbon feedstock in a deposition chamber includes a mass flow meter 1, a control system, a moving sampler 3, and a reaction crucible 5 located within a deposition chamber 6. The moving sampler 3 is mounted on the outer wall of the deposition chamber 6, and its actuating end is connected to the reaction crucible 5 via a sample inlet rod 4. The reaction crucible 5 is used to hold the carbon feedstock. The moving sampler 3 is connected to the control system, which is connected to the mass flow meter 1. The mass flow meter 1 is installed at the air inlet outside the deposition chamber 6 to monitor the rates of carrier gas and carbon source gas entering the deposition chamber 6. Based on the monitored rates, the control system controls the moving sampler 3 to move, thereby changing the position of the reaction crucible 5 relative to the air inlet of the deposition chamber 6.
[0025] Example 2
[0026] Based on Example 1, such as Figure 1 As shown, a guide rail 2 is provided in the deposition chamber, and a slider 8 is installed on the reaction crucible 5. The slider 8 is installed in the guide rail 2. The moving sample injector 3 drives the reaction crucible 5 to move along the guide rail 2. The sample injector 4 and the reaction crucible 5 are both made of high-temperature resistant materials such as stainless steel, graphite or alumina.
[0027] In this embodiment, the velocity v of the carrier gas 载 and the velocity v of the carbon source gas 碳 The sum of V 总 The air flow rate is 2-30 cm / min, and the distance L from the air inlet to the reaction crucible 5 is V. 总 ×(3~10min).
[0028] The moving sampler 3 is a ball screw, which is mounted on the outer wall of the deposition chamber 6, and its nut is connected to the reaction crucible 5 through the sample feed rod 4.
[0029] Example 3
[0030] Based on Example 1, such as Figure 2 As shown, the control system 9 is located between the mass flow meter 1 and the moving sampler 3. The moving sampler 3 is a spiral injection controller, and the actuating end of the spiral injection controller is connected to the reaction crucible 5 through the injection rod 4.
[0031] Application Example 1
[0032] This application embodiment also provides a method for producing hard carbon anodes, which uses the chemical vapor deposition apparatus described in Examples 1-3 and includes the following steps:
[0033] Step 1, with a specific surface area of 1300m² 2 / g, 2000g of porous carbon precursor (carbon raw material) is placed in reaction crucible 5, and reaction crucible 5 is pushed into deposition chamber 6 at a position 300mm away from the gas inlet.
[0034] Step 2: Nitrogen gas is introduced into the deposition chamber 6. The nitrogen gas flows into the deposition chamber 6 from the inlet through the mass flow meter 1 at an initial rate of 1.4 cm / min. After the heating zone 7 in the deposition chamber 6 is heated to 900°C, benzene vapor is introduced at an initial rate of 1.4 cm / min. The mass flow meter 1 monitors the rates of nitrogen gas and benzene vapor in real time. Based on the rates of nitrogen gas and benzene vapor, the control system controls the moving sampler 3 to move the reaction crucible 5, changing the position of the reaction crucible 5 in the deposition chamber 6 so that the diffusion time of benzene vapor matches the time required for pyrolysis and deposition.
[0035] Step 3: Turn off the benzene vapor and cool to room temperature to obtain a hard carbon anode.
[0036] Application Example 2
[0037] This application example also provides another method for producing hard carbon anodes, which uses the chemical vapor deposition apparatus described in Examples 1-3 and includes the following steps:
[0038] Step 1, with a specific surface area of 1300m² 2 / g, 2000g of porous carbon precursor (carbon raw material) is placed in reaction crucible 5, and reaction crucible 5 is pushed into deposition chamber 6 at a position 300mm away from the gas inlet.
[0039] Step 2: Nitrogen gas is introduced into the deposition chamber 6 at a rate of 1.4 cm / min. After the heating zone 7 in the deposition chamber 6 is heated to 900°C, benzene vapor is introduced at a rate of 1.4 cm / min.
[0040] Step 3: After the reaction is complete, the benzene vapor is turned off and the mixture is cooled to room temperature to obtain a hard carbon anode.
[0041] Battery fabrication: The negative electrode active material was the hard carbon negative electrode used in Application Example 1 or Application Example 2. The negative electrode conductive additive was Super-P, and the negative electrode binder was PVDF with a mass ratio of active material to conductive additive and binder of 8:1:1. The negative electrode current collector was copper foil. In the electrolyte, the electrolyte was NaClO4, and the solvent was EC and DEC in a mass ratio of 1:1. Two batteries corresponding to Application Example 1 and Application Example 2 were obtained. The electrochemical performance of the batteries was tested, and the results are shown in Table 1.
[0042] Table 1: Test results of Application Example 1 and Application Example 2
[0043] Group Reversible specific capacity (mAh / g) Low potential platform capacity (mAh / g) First-time coulomb efficiency (%) Application Example 1 530 390 89 Application Example 2 230 30 40
[0044] As can be seen from Table 1, when preparing hard carbon anodes, if the position of the carbon raw material is adjusted to match the diffusion time of the carbon source gas and the time required for cracking and deposition, it has a high deposition efficiency, and the reversible capacity, low potential plateau capacity and first coulombic efficiency are significantly increased.
[0045] For ease of explanation, spatial relative terms such as “up,” “down,” “left,” and “right” are used in the embodiments to describe the relationship of one element or feature shown in the figures relative to another element or feature. It should be understood that, in addition to the orientations shown in the figures, spatial terms are intended to include different orientations of the device in use or operation. For example, if the device in the figures is inverted, an element described as being “down” of other elements or features would be positioned “up” of those other elements or features. Therefore, the exemplary term “down” can encompass both up and down orientations. The device may be positioned in other ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.
[0046] Moreover, relational terms such as “first” and “second” are used merely to distinguish one component from another that has the same name, without necessarily requiring or implying any such actual relationship or order between the components.
[0047] The above description is only a preferred embodiment of the present utility model. It should be noted that, for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present utility model, and these improvements and modifications should also be considered within the protection scope of the present utility model.
Claims
1. A chemical vapor deposition apparatus capable of correcting the position of carbon feedstock within a deposition chamber, characterized in that, The device includes a mass flow meter, a control system, a moving sampler, and a reaction crucible located within the deposition chamber. The moving sampler is mounted on the outer wall of the deposition chamber, and its actuating end is connected to the reaction crucible, which is used to hold carbon raw materials. The moving sampler is connected to the control system, which is connected to the mass flow meter. The mass flow meter is installed at the air inlet outside the deposition chamber to monitor the rates of carrier gas and carbon source gas entering the deposition chamber. Based on the monitored rates, the control system controls the moving sampler to move, thereby changing the position of the reaction crucible relative to the air inlet of the deposition chamber.
2. The chemical vapor deposition apparatus according to claim 1, characterized in that, A guide rail is provided in the deposition chamber, and a slider is installed on the reaction crucible. The slider is installed inside the guide rail, and the moving sampler drives the reaction crucible to move along the guide rail.
3. The chemical vapor deposition apparatus according to claim 1, characterized in that, The moving end of the mobile sampler is connected to the reaction crucible via the sample injection rod.
4. The chemical vapor deposition apparatus according to claim 1, characterized in that, The deposition chamber is a cylindrical cavity.
5. The chemical vapor deposition apparatus according to claim 3, characterized in that, The injection rod is made of high-temperature resistant materials such as stainless steel, graphite, or alumina.
6. The chemical vapor deposition apparatus according to claim 1, characterized in that, The reaction crucible is made of high-temperature resistant materials such as stainless steel, graphite, or alumina.
7. The chemical vapor deposition apparatus according to claim 1, characterized in that, The sedimentation chamber is the sedimentation chamber of a fluidized bed furnace, tubular furnace, rotary kiln, pusher kiln, roller kiln, conveyor belt kiln, air cushion kiln or walking beam furnace.
8. The chemical vapor deposition apparatus according to claim 1, characterized in that, The distance L from the air inlet to the reaction crucible is V. 总 × (3~10 min), the V 总 The velocity v of the carrier gas 载 and the velocity v of the carbon source gas 碳 The sum of these values is expressed in cm / min.
9. The chemical vapor deposition apparatus according to claim 1, characterized in that, The moving sampler is a ball screw.
10. The chemical vapor deposition apparatus according to claim 1, characterized in that, The moving sampler is a spiral sampler controller.