Phosphorus-carbon negative electrode material production device and preparation method
By employing vacuum heat treatment and temperature control, the problem of combining white phosphorus with activated carbon was solved, enabling the safe and efficient preparation of phosphorus-carbon anode materials. This simplified the process, reduced costs, and yielded excellent electrochemical performance.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- LIYANG HINA BATTERY TECH CO LTD
- Filing Date
- 2024-11-11
- Publication Date
- 2026-05-12
AI Technical Summary
Existing technologies cannot effectively solve the problem of combining white phosphorus with activated carbon, resulting in complex preparation processes, high costs, and safety hazards, especially since white phosphorus reacts with oxygen to produce the highly toxic gas phosphine.
Vacuum heat treatment is used to remove air and moisture from activated carbon. Molten white phosphorus is mixed with activated carbon in a sealed container and heated to convert the white phosphorus into phosphorus vapor, which is then adsorbed into the pores of the activated carbon. Subsequently, it is converted into red phosphorus at a controlled temperature. Finally, the residual white phosphorus is treated with alkaline solution and then washed and dried with water.
The process achieved uniform composite of white phosphorus and activated carbon, which simplified the preparation process, reduced costs, and ensured safety and deposition efficiency, resulting in a phosphorus-carbon anode material with excellent electrochemical performance.
Smart Images
Figure CN122010066A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of battery anode material technology, and in particular to a phosphorus-carbon anode material production apparatus and preparation method. Background Technology
[0002] With the rapid development of industries such as new energy vehicles and smart grids, the demand for high-performance batteries is increasing daily. Phosphorus-carbon anode materials, with their advantages of high energy density, good safety, and long cycle life, are expected to occupy an important position in the future battery market. At the same time, with continuous advancements in research and development technology and further reductions in production costs, the application scope of phosphorus-carbon anode materials will continue to expand.
[0003] Common phosphorus sources include white phosphorus, black phosphorus, and red phosphorus. White phosphorus is prone to spontaneous combustion, while black phosphorus is expensive. Therefore, red phosphorus, with its more stable performance, is chosen in the preparation of phosphorus-carbon anodes. Red phosphorus is combined with activated carbon through evaporation and deposition. Specifically, in this technical route, red phosphorus is mixed with activated carbon, and the red phosphorus is heated to convert into phosphorus vapor. The phosphorus vapor is deposited to convert into white phosphorus, and the white phosphorus is cooled to convert back into red phosphorus. To avoid incomplete conversion and residual white phosphorus causing spontaneous combustion, CS2 or alkaline solution is usually introduced to dissolve or remove the white phosphorus through a reaction. Obviously, using white phosphorus directly as the phosphorus source can effectively simplify the process and reduce costs. However, activated carbon has a highly porous structure that stores O2, and white phosphorus easily reacts with O2 to form P2O5. Moreover, activated carbon easily absorbs water, and water reacts with white phosphorus to produce highly toxic phosphine gas. Therefore, the combination of white phosphorus and activated carbon has always been a difficult technical problem to solve.
[0004] To address this issue, existing technologies employ liquid-phase methods, such as ethylenediamine-assisted phosphorus conversion combined with activated carbon. While this avoids the spontaneous combustion of white phosphorus, it adds a liquid-phase treatment step and post-processing operations, requiring additional investment and resources in terms of safety, environmental protection, personnel safety, and environmental protection equipment. Furthermore, solvated phosphorus is more difficult to diffuse into the pores of activated carbon than phosphorus vapor molecules, and the introduced solvent molecules compete with phosphorus for adsorption, affecting deposition efficiency.
[0005] In the phosphorus chemical industry, white phosphorus is first prepared by smelting phosphate rock. White phosphorus is then used as a basic raw material to further prepare red phosphorus, black phosphorus, and other phosphorus compounds. It is evident that using white phosphorus as a phosphorus source to prepare phosphorus-carbon anodes has significant technological and cost advantages. However, the first challenge is to solve the problem of the difficulty in combining white phosphorus with activated carbon, and to avoid the flammability risk during the use of white phosphorus. Therefore, this application is submitted. Summary of the Invention
[0006] In view of the above-mentioned shortcomings of the prior art, the present invention provides a phosphorus-carbon anode material production apparatus and preparation method.
[0007] To achieve the above objectives, the main technical solutions adopted by the present invention include:
[0008] On the one hand, this invention proposes a method for preparing phosphorus-carbon anode materials, comprising the following steps:
[0009] S1. After placing the activated carbon in a sealed container, vacuum heat treatment is performed on the sealed container to remove the activated carbon, air, and moisture from the sealed container.
[0010] S2. Pour molten white phosphorus into a sealed container in proportion and mechanically stir to mix evenly;
[0011] S3. Heat the sealed container and stir continuously to convert white phosphorus into phosphorus vapor and adsorb it into the pores of activated carbon.
[0012] S4. Adjust the temperature inside the sealed container to the conversion temperature and keep it warm so that the phosphorus vapor adsorbed in the pores of the activated carbon is converted into red phosphorus.
[0013] S5. Cool the sealed container, then inject alkaline solution into it and heat it to wash away residual white phosphorus. The waste gas generated during the process is discharged from the sealed container and further treated.
[0014] S6. Washing, drying, and packaging.
[0015] Step S1 removes the air and moisture adsorbed by the activated carbon and the air and moisture inside the sealed container, ensuring that phosphorus does not come into contact with water or air, thus removing obstacles for the composite of white phosphorus and activated carbon. Step S2 uses liquid white phosphorus, the cheapest phosphorus source in the phosphorus chemical industry, which reduces costs and simplifies the process. Steps S3 and S4 achieve uniform phosphorus-carbon composite. Step S5 removes residual white phosphorus from the system and discharges the waste gas generated from white phosphorus removal into the sealed container for post-treatment to prevent excessive pressure in the sealed container and potential safety hazards. Step S6 removes residual alkali left in the system during alkali washing with water, followed by drying and packaging to obtain the final product.
[0016] Preferably, in step S1, during the vacuum heat treatment, heating is started simultaneously with vacuuming. The sealed container is first evacuated to a vacuum degree ≤ -0.1MPa, heated to 150-300℃, then kept at this temperature for 2-24 hours while maintaining a vacuum degree ≤ -0.1MPa. After the heat preservation is completed, the temperature is lowered to 80-240℃ and maintained, so as to proceed to step S2.
[0017] Preferably, in step S3, heating raises the temperature inside the sealed container to 350-400°C.
[0018] Preferably, in step S4, the conversion temperature is 260-300℃.
[0019] Preferably, in step S5, after the cooling treatment, the temperature inside the sealed container is 40-100℃.
[0020] Preferably, in step S5, after the cooling treatment, inert gas is injected and the pressure of the sealed container is monitored. When the vacuum degree is ≥0MPa, alkaline solution is injected. After the alkaline solution is injected, the temperature inside the sealed container is controlled to be 60-100℃. During alkaline washing, inert gas is introduced into the sealed container to purge it so that the generated waste gas can be discharged and transferred to environmental protection equipment for further processing.
[0021] Preferably, in step S6, the material is washed until it is neutral, and both the drying and packaging are carried out in a vacuum environment.
[0022] On the other hand, the present invention proposes a phosphorus-carbon anode material production device, including a cover and a conversion tank that are detachably connected and have independent heating functions. The cover is provided with an air inlet, an exhaust outlet, a water inlet, a feed inlet and a pressure relief valve. A check valve is connected to the feed inlet. A pressure gauge for monitoring the air pressure inside the conversion tank is also installed on the cover. The pressure gauge is connected to the conversion tank through a pressure gauge buffer. A stirring mechanism and a thermocouple are provided inside the conversion tank.
[0023] Preferably, the pressure gauge buffer includes a housing and a coolant pipe located inside the housing. The coolant pipe has a serpentine structure with one end being a coolant inlet and the other end being a coolant outlet. A cooling mesh is also connected below the horizontal section of the coolant pipe. The cooling mesh has a flat-topped conical structure with its larger end connected to the horizontal section and its smaller end facing downwards.
[0024] Preferably, it also includes a conversion tank support base, a flip shaft is fixedly connected to the conversion tank, the conversion tank is rotatably connected to the conversion tank support base via the flip shaft, and a flip structure for controlling the rotation of the flip shaft is connected to the flip shaft.
[0025] Compared with existing technologies, this invention solves the problem of difficult composite of white phosphorus and activated carbon by using a specific device, and realizes the preparation of phosphorus-carbon anode materials using white phosphorus as phosphorus source. This helps to simplify the preparation operation, reduce the production cost of phosphorus-carbon anode materials, and the preparation method is safe, efficient, easy to operate and will not affect the phosphorus deposition efficiency. Attached Figure Description
[0026] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0027] Figure 1This is a schematic flowchart of a method for preparing a phosphorus-carbon anode material according to the present invention;
[0028] Figure 2 This is a front view of a phosphorus-carbon anode material production apparatus according to the present invention;
[0029] Figure 3 This is a top view of a phosphorus-carbon anode material production apparatus according to the present invention;
[0030] Figure 4 for Figure 2 Schematic diagram of the structure of the pressure gauge buffer;
[0031] Figure 5 The electrochemical performance diagram of the phosphorus-carbon composite material prepared using white phosphorus as the phosphorus source is shown.
[0032] Figure 6 The figure shows the electrochemical performance of a phosphorus-carbon composite material prepared using red phosphorus as the phosphorus source.
[0033] In the diagram: 1. Pressure gauge; 2. Pressure gauge buffer; 21. Coolant inlet; 22. Coolant outlet; 23. Cooling mesh; 3. Tilting structure; 4. Cover; 5. Exhaust port; 6. Sealing flange; 7. Tilting shaft; 8. Agitator motor; 9. Agitator rod; 10. Water inlet; 11. Air inlet; 12. Feed inlet; 13. Agitator paddle; 14. Conversion tank; 15. Check valve; 16. Heat transfer medium heating jacket I; 17. Heat transfer medium heating jacket II; 18. Conversion tank support; 19. Heat transfer medium inlet II; 20. Heat transfer medium outlet II; 21. Heat transfer medium inlet I; 22. Heat transfer medium outlet I; 23. Pressure relief valve; 24. Thermocouple. Detailed Implementation
[0034] The technical solutions in the embodiments of this application will be clearly and completely described below with reference to the embodiments of this application. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.
[0035] It should be noted that: any components or structures not described in detail below are made using conventional techniques in the field or are common knowledge in the field.
[0036] like Figures 2-4As shown in the figure: This invention proposes a phosphorus-carbon anode material production device, including a cover 4 and a conversion tank 14 that are detachably connected and have independent heating functions. The cover 4 is provided with an air inlet 11, an exhaust outlet 5, a water inlet 10, a feeding inlet 12 and a pressure relief valve 23. A check valve 15 is connected to the feeding inlet 12. The cover 4 is also equipped with a pressure gauge 1 for monitoring the air pressure inside the conversion tank 14. The pressure gauge 1 is connected to the conversion tank 14 through a pressure gauge buffer 2. The conversion tank 14 is provided with a stirring mechanism and a thermocouple 24. The stirring mechanism can mechanically stir the material inside the conversion tank 14, and the thermocouple 24 can monitor the temperature inside the conversion tank 14 at any time.
[0037] In this embodiment, the cover 4 and the conversion tank 14 are detachably connected. The specific connection method is the existing technology, such as being connected through the sealing flange 6.
[0038] In this embodiment, electromagnetic control valves are respectively installed on the exhaust port 5, water inlet 10, and air inlet 11 to achieve automated control.
[0039] In this embodiment, the stirring mechanism is existing technology, and for example, it can be as follows: The stirring mechanism includes a stirring motor 8, a stirring rod 9 and a stirring paddle 13. The stirring motor 8 is fixedly installed on the upper surface of the cover 4, and the stirring paddle 13 is located inside the conversion tank 14. Driven by the stirring motor 8, the stirring rod 9 rotates and drives the stirring paddle 13 to rotate to mechanically stir the material inside the conversion tank 14.
[0040] In this embodiment, both the cover 4 and the conversion tank 14 have a heating system, which is a prior art system, such as using a heat-conducting medium for heating. Both the cover 4 and the conversion tank 14 are equipped with heating jackets, and the heating function is achieved by the heat-conducting medium entering the heating jacket. Specifically, the cover 4 has a heat-conducting medium heating jacket II 17, which has a heat-conducting medium inlet II 19 and a heat-conducting medium outlet II 20. The heat-conducting medium enters the heat-conducting medium heating jacket II 17 through the heat-conducting medium inlet II 19 and exits through the heat-conducting medium outlet II 20. The conversion tank 14 has a heat-conducting medium heating jacket I 16, which has a heat-conducting medium inlet I 21 and a heat-conducting medium outlet I 22. The heat-conducting medium can be selected from various sources, such as water, steam, molten salt, and oil. The present invention preferably uses heat transfer oil, including mineral oil and synthetic oil. Heat transfer oil has high thermal stability and heat capacity, can maintain stable performance at high temperatures, and also has good lubricity and sealing properties, which can protect the cover 4, the conversion tank 14 and the materials from wear and corrosion.
[0041] As a preferred technical solution, in another embodiment of the present invention, the pressure gauge buffer 2 includes a housing and a coolant pipe located inside the housing. The coolant pipe has a serpentine structure with one end being a coolant inlet 21 and the other end being a coolant outlet 22. A cooling net 23 is also connected below the horizontal section of the coolant pipe. The cooling net 23 has a flat-topped conical structure with its larger end connected to the horizontal section and its smaller end facing downwards.
[0042] Coolant flows through the coolant pipes. The coolant is a current technology, such as water or cooling oil. The coolant enters through the coolant inlet 21 and exits through the coolant outlet 22. The serpentine structure of the coolant pipes results in higher condensation efficiency. The coolant pipes are connected to the cooling net 23, enabling heat transfer between them. The unique conical design of the cooling net 23 significantly increases the collection area, which helps to achieve full condensation and ensures that the condensed droplets fall into the conversion tank 14 in a timely manner.
[0043] It should be noted that the pressure gauge buffer 2 has a built-in cooling and heating system (not shown in the figure) for controlling the temperature of the pressure gauge buffer 2. This cooling and heating system is existing technology, such as using jacketed heat transfer oil as the cooling and heating system, in order to achieve flexible control of the temperature of the pressure gauge buffer 2.
[0044] As a preferred technical solution, another embodiment of the present invention further includes a conversion tank support 18, a flip shaft 7 fixedly connected to the conversion tank 14, two bearing seats provided on the conversion tank support 18, the flip shaft 7 being rotatably connected to the bearing seats, the conversion tank 14 being rotatably connected to the conversion tank support 18 via the flip shaft 7, and a flip structure 3 for controlling the rotation of the flip shaft 7 being connected to the flip shaft 7.
[0045] The flipping structure 3 is existing technology and can be selected in various ways. For example, it can be an operating handle that is fixedly connected to the flipping shaft 7. By acting on the operating handle, the rotation of the flipping shaft 7 can be adjusted to control the tilt of the conversion tank 14, thereby achieving the purpose of pouring the material in the conversion tank 14 into other containers.
[0046] The above embodiments are merely examples and are not intended to limit the present invention. Other existing implementations are also possible, such as: the flipping shaft 7 is fixedly installed on the conversion tank support 18, the conversion tank 14 is rotatably connected to the flipping shaft 7, the flipping structure 3 is fixedly connected to the conversion tank 14 and is specifically an operating handle, the operating handle is manually operated to control the tilt of the conversion tank 14, thereby achieving the purpose of pouring the material in the conversion tank 14 into other containers.
[0047] Of course, the flipping structure 3 can also adopt the existing automated flipping structure. This structure is not an improvement of the present invention, so the present invention will not elaborate on it.
[0048] like Figure 3 As shown: This invention also proposes a method for preparing phosphorus-carbon anode materials, comprising the following steps:
[0049] S1. After placing the activated carbon in a sealed container, vacuum heat treatment is performed on the sealed container to remove the activated carbon, air, and moisture from the sealed container.
[0050] S2. Pour molten white phosphorus into a sealed container in proportion and mechanically stir to mix evenly;
[0051] S3. Heat the sealed container and stir continuously to convert white phosphorus into phosphorus vapor and adsorb it into the pores of activated carbon.
[0052] S4. Adjust the temperature inside the sealed container to the conversion temperature and keep it warm so that the phosphorus vapor adsorbed in the pores of the activated carbon is converted into red phosphorus.
[0053] S5. Cool the sealed container, then inject alkaline solution into it and heat it to wash away residual white phosphorus. The waste gas generated during the process is discharged from the sealed container and further treated.
[0054] S6. Washing, drying, and packaging.
[0055] Furthermore, the above preparation method is implemented using the phosphorus-carbon anode material production apparatus proposed in this invention:
[0056] S1. Place activated carbon in conversion tank 14, cover with lid 4, and seal lid 4 to conversion tank 14 through sealing flange 6; close all valves, open the valve of exhaust port 5 and connect vacuum pump to evacuate conversion tank 14 until vacuum degree ≤ -0.1MPa. While evacuating, turn on the heating function of conversion tank 14 to make the temperature inside conversion tank 14 reach 150-300℃, then keep it at this temperature for 2-24 hours and maintain vacuum degree ≤ -0.1MPa. After the heat preservation is completed, cool down to 80-240℃ and maintain it.
[0057] S2. Close the valve of the exhaust port 5, open the valve of the feed port 12, inject molten white phosphorus into the conversion tank 14 in proportion, and at the same time turn on the stirring mechanism to mix the white phosphorus and activated carbon evenly through mechanical stirring.
[0058] S3. Reactivate the heating function of the conversion tank 14 to slowly raise the temperature inside the conversion tank 14 to 350-400℃ and maintain the temperature, converting white phosphorus into phosphorus vapor. The phosphorus vapor gradually enters the activated carbon channels, and the stirring mechanism remains on throughout the process. During this process, the heating function of the cover 4 keeps the temperature of the pressure gauge buffer 2 at about 80℃. When the phosphorus vapor diffuses into the pressure gauge buffer 2, it will condense into liquid white phosphorus and drip into the conversion tank 14, without causing any loss or clogging of the pressure gauge 1. Furthermore, a pulse air valve is installed on the pressure gauge 1 to periodically purge the coolant pipe and cooling screen 23 to prevent phosphorus accumulation and blockage, which would reduce the collection efficiency.
[0059] S4. After the temperature inside the conversion tank 14 is reduced to 260-300℃, it is kept at that temperature to allow the composite white phosphorus to gradually convert into red phosphorus.
[0060] S5. After conversion, lower the temperature inside conversion tank 14 to 40-100℃. At this point, the unconverted white phosphorus is in a liquid state and will not clump due to solidification. Control the temperature of pressure gauge buffer 2 to 40-80℃. Inject inert gas (such as nitrogen or argon) through inlet 11 and monitor the pressure inside conversion tank 14 through pressure gauge 1. When the vacuum degree is ≥0MPa, open exhaust port 5. Then, inject alkaline solution through water inlet 10. The alkaline solution is specifically an aqueous solution of potassium hydroxide and / or sodium hydroxide. After the alkaline solution is injected, close the inlet. Water inlet 10 controls the temperature inside the conversion tank 14 at 60-100℃, allowing the alkaline solution to fully react with the residual white phosphorus. At this time, the temperature of the pressure gauge buffer 2 is lower than the temperature of the water vapor, and the water vapor is condensed through the coolant pipe and drips into the conversion tank 14, without adversely affecting the pressure gauge 1. After the alkaline washing is completed, the valves of the air inlet 11 and the exhaust port 5 are opened. Inert gas is introduced into the conversion tank 14 through the air inlet 11 for purging. The waste gas generated by the alkaline washing is removed from the conversion tank 14 through the exhaust port 5 and transferred to the environmental protection equipment for further treatment.
[0061] S6. Open the sealing flange 6, remove the cover 4, and use the flipping structure 3 to pour the material in the conversion tank 14 into the filter press. Rinse the remaining material in the conversion tank 14 with pure water until all the material is transferred. Wash the material multiple times with water through the filter press until the material is neutral. Then transfer the cleaned material to the vacuum drying oven for vacuum drying. After drying, vacuum package the material to obtain the finished product.
[0062] Phosphorus-carbon anode materials were prepared using white phosphorus and red phosphorus as phosphorus sources, respectively, according to the preparation method described in the previous embodiment. The key technical parameters involved are as follows: In S1, the conversion tank 14 is evacuated until the vacuum degree is -0.1MPa. During evacuation, the heating function of the conversion tank 14 is turned on to make the temperature inside the conversion tank 14 reach 220℃. Then, it is kept at this temperature for 15 hours while maintaining the vacuum degree ≤ -0.1MPa. After the heat preservation is completed, the temperature is lowered to 150℃ and maintained. In S3, the temperature inside the conversion tank 14 is slowly raised to 380℃ and kept at this temperature. In S4, the temperature inside the conversion tank 14 is lowered to 280℃ and kept at this temperature. In S5, the temperature inside the conversion tank 14 is lowered to 70℃, the temperature of the pressure gauge buffer 2 is controlled at 60℃, nitrogen is injected through the air inlet 11 and the pressure inside the conversion tank 14 is monitored through the pressure gauge 1. When the vacuum degree is ≥ 0MPa, the exhaust port 5 is opened, and then the alkaline solution is injected through the water inlet 10. The alkaline solution is a potassium hydroxide aqueous solution. After the alkaline solution is injected, the water inlet 10 is closed, and the temperature inside the conversion tank 14 is controlled at 75℃ to allow the alkaline solution to fully react with the residual white phosphorus.
[0063] The two prepared phosphorus-carbon anode materials were assembled into sodium-ion button cells and their electrochemical performance was tested. The test results for the two anode materials using white phosphorus and red phosphorus as the phosphorus source are shown below. Figure 5 and Figure 6 As shown: When white phosphorus is used as the phosphorus source, it can be converted into phosphorus vapor in the conversion tank 14 and effectively combined with carbon through vapor deposition. Therefore, the resulting anode material exhibits excellent electrochemical performance. When red phosphorus is used as the phosphorus source, the red phosphorus cannot be converted into gaseous state and cannot be effectively combined with carbon because the reaction system temperature is lower than the sublimation temperature of red phosphorus. Therefore, the resulting anode material has poor electrochemical performance.
[0064] In summary, this invention solves the problem of difficult composite formation of white phosphorus and activated carbon by employing a specific device, and realizes the preparation of phosphorus-carbon anode materials with good electrochemical performance using white phosphorus as the phosphorus source. The preparation method of phosphorus-carbon anode materials proposed in this invention helps to simplify the preparation operation, reduce the production cost of phosphorus-carbon anode materials, and the preparation method is safe, efficient, easy to operate, and has industrialization prospects.
[0065] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make modifications, alterations, substitutions, and variations to the above embodiments within the scope of the present invention. Furthermore, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of the different embodiments or examples.
Claims
1. A method for preparing a phosphorus-carbon anode material, characterized in that: The following steps are included: S1. After placing the activated carbon in a sealed container, vacuum heat treatment is performed on the sealed container to remove the activated carbon, air, and moisture from the sealed container. S2. Pour molten white phosphorus into a sealed container in proportion and mechanically stir to mix evenly; S3. Heat the sealed container and stir continuously to convert white phosphorus into phosphorus vapor and adsorb it into the pores of activated carbon. S4. Adjust the temperature inside the sealed container to the conversion temperature and keep it warm so that the phosphorus vapor adsorbed in the pores of the activated carbon is converted into red phosphorus. S5. Cool the sealed container, then inject alkaline solution into it and heat it to wash away residual white phosphorus. The waste gas generated during the process is discharged from the sealed container and further treated. S6. Washing, drying, and packaging.
2. The method for preparing phosphorus-carbon anode material according to claim 1, characterized in that: In step S1, during the vacuum heat treatment, heating is started simultaneously with vacuuming. First, the sealed container is evacuated to a vacuum degree ≤ -0.1MPa and heated to 150-300℃. Then, it is kept at this temperature for 2-24 hours while maintaining a vacuum degree ≤ -0.1MPa. After the heat preservation is completed, the temperature is lowered to 80-240℃ and maintained to proceed to step S2.
3. The method for preparing phosphorus-carbon anode material according to claim 1, characterized in that: In step S3, heating raises the temperature inside the sealed container to 350-400℃.
4. The method for preparing phosphorus-carbon anode material according to claim 1, characterized in that: In step S4, the conversion temperature is 260-300℃.
5. The method for preparing phosphorus-carbon anode material according to claim 1, characterized in that: In step S5, after the cooling process, the temperature inside the sealed container is 40-100℃.
6. The method for preparing phosphorus-carbon anode material according to claim 1, characterized in that: In step S5, after the cooling treatment, inert gas is injected and the pressure of the sealed container is monitored. When the vacuum degree is ≥0MPa, alkaline solution is injected. After the alkaline solution is injected, the temperature inside the sealed container is controlled at 60-100℃. During alkaline washing, inert gas is purged into the sealed container so that the generated waste gas can be discharged and transferred to the environmental protection equipment for further treatment.
7. The method for preparing phosphorus-carbon anode material according to claim 1, characterized in that: In step S6, the material is washed with water until it is neutral, and both the drying and packaging are carried out in a vacuum environment.
8. A phosphorus-carbon anode material production apparatus, characterized in that: It includes a detachable cover (4) and a conversion tank (14) with independent heating functions. The cover (4) is provided with an air inlet (11), an exhaust port (5), a water inlet (10), a feed port (12) and a pressure relief valve (23). A check valve (15) is connected to the feed port (12). A pressure gauge (1) for monitoring the air pressure inside the conversion tank (14) is also installed on the cover (4). The pressure gauge (1) is connected to the conversion tank (14) through a pressure gauge buffer (2). A stirring mechanism and a thermocouple (24) are provided inside the conversion tank (14).
9. The phosphorus-carbon anode material production apparatus according to claim 8, characterized in that: The pressure gauge buffer (2) includes a housing and a coolant pipe located inside the housing. The coolant pipe has a serpentine structure with one end being a coolant inlet (21) and the other end being a coolant outlet (22). A cooling net (23) is also connected below the horizontal section of the coolant pipe. The cooling net (23) has a flat-topped conical structure with its large end connected to the horizontal section and its small end facing downwards.
10. The phosphorus-carbon anode material production apparatus according to claim 8, characterized in that: It also includes a conversion tank support base (18), a flip shaft (7) is fixedly connected to the conversion tank (14), the conversion tank (14) is rotatably connected to the conversion tank support base (18) via the flip shaft (7), and a flip structure (3) for controlling the rotation of the flip shaft (7) is connected to the flip shaft (7).