Powder grinding device and method for new energy negative electrode material

Abstract

The invention discloses a powder grinding device and method for a new energy negative electrode material. The device comprises a barrel, a stirring mechanism and a powder selecting mechanism, wherein a feeding screw, a medium adding port and an air inlet are arranged on the side wall of the barrel; the stirring mechanism comprises a driving motor I and a stirring shaft, a stirring screw is arranged on the stirring shaft, and the stirring screw is located in the cylinder body and located below the medium adding port and the air inlet; the powder selecting mechanism comprises a rotor cage arranged outside the stirring shaft in a sleeving mode, the rotor cage is located in the barrel and located above the air inlet, an annular connecting plate used for blocking an opening in the top of the barrel is arranged at the top of the barrel, an air outlet is formed in the middle of the annular connecting plate, and a plurality of guide plates are arranged on the lower surface of the annular connecting plate in an annular array mode and surround the rotor cage. A return hopper is arranged at the bottom of the guide plate. The grinding effect is enhanced, the selective grinding effect is achieved, the powder making efficiency is high, the shell does not need to be driven to move, and the powder making energy consumption is reduced; the device is internally self-graded, the product sphericity is good, and the rejection rate is low.

Description

Technical Field

[0001] The present invention belongs to the technical field of new energy negative electrode material processing, and in particular relates to a new energy negative electrode material powder grinding and pulverizing device and method. Background Art

[0002] In recent years, the new energy battery industry has experienced rapid growth, placing increasing demands on the performance of anode materials. Anode materials play a crucial role in improving battery capacity and performance. Their production processes and equipment, particularly the powder production process, play a crucial role in the performance of the final product. Strict control of parameters such as powder particle size distribution and quality is crucial to ensure the electrochemical performance and stability of the final product. Consequently, continuous innovation in grinding and powder production technologies is necessary to improve the performance and quality of anode materials.

[0003] The negative electrode material has very strict quality indicators for the raw material micro powders such as petroleum coke and graphite: the required product particle size must be very fine and narrow, and the product must have high sphericity. Taking the product fineness requirements of a certain petroleum coke negative electrode material as an example, its D min (μm) ≥ 2.0, D 10 (μm) = 7.0 ± 1.5, D 50 (μm) = 15.0 ± 1.5, D 90 (μm)≤35.0, D 99 (μm)≤45.0, D max (μm) ≤ 60.0. The stringent particle size requirements for negative electrode materials make it difficult for many processes and equipment in the industry to meet these requirements. This not only produces a large number of unusable substandard products, wasting resources, but also inappropriate grinding mechanisms significantly increase pulverizing energy consumption, raising production costs. This results in rapid wear, low yields, and high energy consumption in existing negative electrode material pulverizing equipment.

[0004] Currently, there are two methods for producing negative electrode materials using dry and wet methods. The main grinding equipment includes mechanical mills, air jet mills, roller mills, ball mills, and horizontal sand mills. From a production process perspective, after producing negative electrode materials, they require shaping, grading, additive mixing, coating, molding, calcination, or graphitization. Most of these processes must be performed on a dry basis. Therefore, wet pulverization generally involves additional dehydration and drying, leading to a complex process flow. From the perspective of grinding equipment, mechanical mills, air jet mills, and roller mills, which rely on impact and pressure mechanisms for crushing, are noisy and produce poorly shaped and spherical products, requiring complex sphericity shaping processes. Ball mills and horizontal sand mills cannot promptly discharge qualified products, resulting in severe over-grinding, high scrap rates, high energy consumption, and rapid equipment wear and tear. Furthermore, current equipment generally requires a separate grading system, resulting in complex process flows and some equipment being difficult to scale up and expand.

[0005] At present, the new energy industry is experiencing explosive growth, resulting in a huge production capacity gap in new energy negative electrode materials. In addition, the cost and price of negative electrode material products are high, which inevitably requires the negative electrode material grinding and pulverizing technology and equipment to develop in the direction of high production capacity, high yield and low wear. It is urgent to find more energy-saving and efficient grinding and pulverizing equipment and methods. Summary of the Invention

[0006] In view of the shortcomings of the existing methods, the present invention provides a new energy negative electrode material grinding and pulverizing device and method.

[0007] To achieve the above object, the present invention adopts the following technical solutions: A new energy negative electrode material grinding and pulverizing device comprises a cylinder, a stirring mechanism and a powder selection mechanism, wherein a feed screw, a medium addition port and an air inlet are provided on the side wall of the cylinder, the feed screw is located at the lower end of the side wall, and the medium addition port and the air inlet are located at the upper end of the side wall; the stirring mechanism comprises a driving motor and a stirring shaft, the driving motor is arranged at the top of the cylinder for providing power to the stirring shaft, a stirring screw is arranged on the stirring shaft, the stirring screw is located inside the cylinder and below the medium addition port and the air inlet; the powder selection mechanism comprises a rotor cage sleeved on the outside of the stirring shaft, the rotor cage is located inside the cylinder and above the air inlet, an annular connecting plate for sealing the opening at the top of the cylinder is provided on the top of the cylinder, an air outlet is formed in the middle of the annular connecting plate, a plurality of guide plates are arranged in an annular array on the lower surface of the annular connecting plate, the guide plates enclose the rotor cage, and a return hopper is provided at the bottom of the guide plate.

[0008] Preferably, the return hopper is in the shape of a truncated cone, with the large end opening upward and fixed to the bottom of the guide plate, the small end opening downward, and the diameter being larger than the diameter of the stirring shaft, and the stirring shaft passes through the return hopper.

[0009] Preferably, the rotor cage includes a rotating shaft sleeved on the outer surface of the stirring shaft, a conical throwing barrel arranged at the lower end of the rotating shaft, and a multi-layer annular frame arranged outside the conical throwing barrel, rotor blades are arranged between the annular frames, and a fixing rod is arranged between the annular frame and the conical throwing barrel.

[0010] Preferably, the powder selection mechanism further includes a second drive motor arranged at the top of the cylinder, a driving pulley connected to the output end of the second drive motor, a driven pulley arranged outside the rotating shaft, and a belt connecting the driving pulley and the driven pulley.

[0011] Preferably, the rotating shaft and the stirring shaft are connected via a bearing.

[0012] Preferably, the stirring screw has a double helix structure or a multi-helix structure.

[0013] Preferably, a one-way air lock valve is provided at the medium inlet.

[0014] Preferably, a guide tube is provided at the air outlet, a dust collecting device is provided at the outlet of the guide tube, and a fan is provided on the air outlet pipe of the dust collecting device.

[0015] A method for grinding and pulverizing new energy negative electrode materials using the above-mentioned device comprises the following steps: S1. The medium balls are fed into the grinding area at the bottom of the cylinder through the medium feeding port according to a certain particle size distribution. The driving motor drives the stirring shaft to rotate, and the stirring spiral drives the medium balls to make high-speed circular motion and up and down motion along the cylinder; S2. After the pre-crushing process, the material is fed into the grinding area at the bottom of the cylinder by the feed screw pressure. It is crushed and fined under the high-speed collision, extrusion and friction grinding of the medium balls. The ground fine material gradually moves upward through the gap between the medium balls and the lifting effect of the stirring screw. At the air inlet, it forms a gas-solid mixing zone with the air fed from the outside. S3. Air enters from the air inlet and is fully mixed with the ground fine material in the gas-solid mixing zone, driving the ground fine material upward. During the upward movement of the airflow, the particles whose own gravity is greater than the buoyancy of the airflow fall back to the grinding zone at the bottom of the cylinder to continue to be ground. The finer particles rise with the airflow, are rectified by the guide plate, and are classified in the centrifugal classification zone where the rotor cage is located; S4. After classification in the centrifugal classification zone, the coarser particles are intercepted by the rotor cage and fall back to the grinding zone at the bottom of the cylinder through the return hopper to continue to be ground. The finer materials are discharged from the air outlet with the air flow and collected by the dust collection device to obtain the final qualified products.

[0016] Preferably, step S4 specifically includes: S4, the second drive belt of the driving motor drives the rotor cage to rotate. The classification particle size is controlled by adjusting the rotor cage speed. Coarser particles larger than the classification particle size are intercepted by the rotor cage, fall into the return hopper through the gap between the rotor blades and the guide plate, and then fall back to the grinding area at the bottom of the cylinder for further grinding. Finer materials smaller than the classification particle size are discharged from the air outlet with the air flow and collected by the dust collection device to obtain the final qualified product.

[0017] The positive beneficial effects of the present invention are: 1. The present invention adopts a dry pulverizing device to grind new energy negative electrode materials. Compared with the wet method, it reduces the dehydration and drying processes. It has a vertical structure, a fixed cylinder, and a small footprint. The stirring spiral drives the medium ball to move at a high speed. Under the action of strong stirring, centrifugal force and lifting force, the medium ball and the material are fully in contact with each other and have a high relative speed. The impact grinding effect is strong, and a material-carrying airflow is formed with the air at the air inlet to continue to move upward. The particles whose own gravity is greater than the buoyancy of the airflow fall back to the grinding area at the lower part of the cylinder to continue to be ground. The finer particles rise with the airflow and are rectified by the guide plate and are classified by the rotor cage. The coarser particles larger than the classified particle size are intercepted by the rotor cage, fall into the return hopper and fall back to the grinding area at the lower part of the cylinder to continue to be ground. The finer materials smaller than the classified particle size are discharged from the air outlet with the airflow and collected by the dust collecting device to obtain the final qualified product. The present invention strengthens the grinding effect and realizes selective grinding until the material meets the particle size requirements. It has high powder making efficiency and is significantly different from impact and pressure crushing equipment. Compared with drum mills, it does not need to drive the shell movement, which improves energy utilization efficiency and reduces powder making energy consumption. At the same time, it realizes the integration of powder making and grading, shortens the process flow, and the product particle size meets the requirements, has good sphericity, large specific surface area, low scrap rate and high resource utilization rate.

[0018] 2. Compared with traditional ball mills, air flow mills, roller mills, horizontal pulverizers, vertical mills and other equipment, the device of the present invention has the following advantages: 1) Reasonable technology and simple process: ① Using dry pulverizing technology to reduce the steps of slurry preparation, product dehydration and drying; ② The device realizes self-grading and directly discharges qualified products, reducing additional grading and circulation devices and shortening the milling process.

[0019] 2) Energy saving and high efficiency: ①The stirring spiral drives the medium ball to move at high speed, eliminating the useless power consumption of the cylinder and other components, and significantly reducing the power consumption of the powder making system; ②The working mechanism is mainly grinding. Large media balls grind coarse particles, and small media balls grind fine particles, achieving selective grinding of materials, more scientific and reasonable energy distribution, and improving energy utilization efficiency; ③The stirring device has high speed, high energy density and large processing capacity per unit volume, which can effectively improve production capacity and is suitable for large-scale and expanded production scale; ④ An internal grading mechanism is set up to discharge qualified products in time, reduce over-grinding, further increase system output and reduce system power consumption.

[0020] 3) Good product quality and low scrap rate: ① Selective grinding products have a narrow particle size range, high sphericity and large specific surface area; ② The grinding area, gas-solid mixing area and centrifugal classification area in the cylinder work together to grind the powder layer by layer, discharge qualified products in time, reduce over-grinding, improve product quality and reduce scrap rate.

[0021] 4) Advanced equipment, strong adaptability and environmental friendliness: ①The device adopts a vertical structure, which occupies a small area, has a simple process, is easy to operate and manage, and saves labor costs; ② The device is airtight with negative pressure air intake or air is blown into the device from the air inlet by an external fan. The device is sealed as a whole, and the negative pressure air intake facilitates the formation of a circulating negative pressure air path inside. While completing the classification function, it can also effectively reduce the temperature of the grinding area inside the device and reduce dust emission.

[0022] 5) The dielectric ball is a steel ball or a ceramic ball: ①Using steel balls as grinding media can reduce equipment wear and maintenance costs, extend the liner replacement cycle, and improve the operating rate; ② Using ceramic balls as grinding media can avoid the introduction of metal impurities and improve the performance of negative electrode material products.

[0023] 6) Wide range of applications: ① The device and method of the present invention are not limited to the dry powdering of new energy negative electrode materials, but are also applicable to the dry powdering of cement materials, mineral materials and other materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a schematic diagram of the structure of the new energy negative electrode material grinding and pulverizing device of the present invention; Figure 2 This is the main view of the rotor cage; Figure 3 It is a schematic diagram of the guide plate and return hopper structure; Figure 4 This is a top view of the rotor cage, guide plate and return hopper; In the figure: 1-cylinder, 2-driving motor 1, 3-speed reducer 1, 4-stirring shaft, 5-stirring screw, 6-feeding screw, 7-medium adding port, 8-one-way air lock valve, 9-driving motor 2, 10-speed reducer 2, 11-pulley 1, 12-pulley 2, 13-belt, 14-rotor cage, 141-rotating shaft, 142-conical throwing barrel, 143-annular frame, 144-rotor blades, 145-fixing rod, 15-air inlet, 16-air outlet, 17-guide plate, 18-annular connecting plate, 19-return hopper, 20-drainage barrel, 21-dust collecting device, 22-fan. DETAILED DESCRIPTION

[0025] The present invention is further described below with reference to some specific embodiments.

[0026] Example 1 See also Figures 1 to 4 A new energy negative electrode material grinding and pulverizing device includes a cylinder 1, a stirring mechanism and a powder selection mechanism. A feeding screw 6, a medium addition port 7 and an air inlet 15 are provided on the side wall of the cylinder 1. The feeding screw 6 is located at the lower end of the side wall. The feeding screw 6 conveys the material into the cylinder 1 through an external spiral mechanism. The feeding direction of the feeding screw 6 is radial feeding (the central axis of the feeding screw is coplanar with the central axis of the cylinder and perpendicular to each other) or tangential feeding (the central axis of the feeding screw is not coplanar with the central axis of the cylinder and is perpendicular to the diameter of the cylinder). Tangential feeding is smoother. Figure 1 The vertical feeding is shown in the figure; the medium adding port 7 and the air inlet 15 are located at the upper end of the side wall. At least one air inlet 15 is provided. The air inlet 15 is evenly arranged perpendicular to the cylinder (the central axis of the air inlet is coplanar with the central axis of the cylinder and perpendicular to each other) to form radial air inlet, or the air inlet 15 is tangentially arranged with the cylinder (the central axis of the air inlet is not coplanar with the central axis of the cylinder and is perpendicular to the diameter of the cylinder) to form tangential air inlet. Tangential air inlet is conducive to forming a stable wind field, which is convenient for taking away qualified materials in time. Figure 1 The vertical cylinder is shown as an air inlet; The stirring mechanism includes a drive motor 2 arranged at the top of the cylinder, a reducer 3 connected to the output end of the drive motor 2, and a stirring shaft 4 connected to the output end of the reducer 3. The drive motor 2 is used to provide power for the stirring shaft 4. The position of the drive motor 2 is fixed to the position of the cylinder 1. The stirring shaft 4 is provided with a stirring screw 5. The stirring screw 5 is located inside the cylinder 1 and below the medium addition port 7 and the air inlet 15. The powder selection mechanism includes a rotor cage 14 sleeved on the outside of the stirring shaft 4. The rotor cage 14 is located inside the cylinder 1 and above the air inlet 15. An annular connecting plate 18 is provided on the top of the cylinder 1 for sealing the top opening of the cylinder 1. The middle part of the annular connecting plate 18 forms an air outlet 16. A plurality of guide plates 17 are provided in a circular array on the lower surface of the annular connecting plate 18. The guide plates 17 enclose the rotor cage 14. A return hopper 19 is provided at the bottom of the guide plate 17.

[0027] The present invention adopts a dry pulverizing device to grind new energy negative electrode materials. Compared with the wet method, it reduces the dehydration and drying processes. It has a vertical structure, a fixed cylinder, and a small footprint. The stirring spiral drives the medium ball to move at high speed. Under the action of strong stirring, centrifugal force and lifting force, the medium ball and the material are fully in contact with the medium ball and have a high relative speed. The impact grinding effect is strong, and a material-carrying airflow is formed with the air at the air inlet to continue to move upward. The particles whose own gravity is greater than the buoyancy of the airflow fall back to the grinding area at the lower part of the cylinder to continue to be ground. The finer particles rise with the airflow and are rectified by the guide plate and are classified by the rotor cage. The coarser particles larger than the classified particle size are intercepted by the rotor cage, fall into the return hopper and fall back to the grinding area at the lower part of the cylinder to continue to be ground. The finer materials smaller than the classified particle size are discharged from the air outlet with the airflow and collected by the dust collecting device to obtain the final qualified product. The present invention strengthens the grinding effect and realizes selective grinding until the material meets the particle size requirements. The powder making efficiency is high, and there is no need to drive the shell to move, which improves the energy utilization efficiency and reduces the energy consumption of powder making. At the same time, it realizes the integration of powder making and grading, shortens the process flow, and the product particle size meets the requirements, has good sphericity, large specific surface area, low scrap rate and high resource utilization rate.

[0028] Furthermore, the return hopper 19 is truncated into a cone shape, with its large end opening upward and fixed to the bottom of the guide plate 17, and its small end opening downward. Its diameter is larger than that of the agitator shaft 4, which passes through the return hopper 19. By configuring the return hopper as a cone structure with a larger top and a smaller bottom, the coarse material that does not pass through the rotor cage can be guided to the grinding area at the bottom of the cylinder for further grinding. According to the principles of fluid dynamics, this also prevents the entrained airflow from entering the powder selection mechanism from this point.

[0029] Furthermore, the rotor cage 14 includes a rotating shaft 141 sleeved on the outer surface of the stirring shaft 4, a conical ejection barrel 142 disposed at the lower end of the rotating shaft 141, and a multi-layered annular frame 143 disposed outside the conical ejection barrel 142. Rotor blades 144 are disposed between the annular frames 143, and a fixing rod 145 is fixedly connected between the annular frame 143 and the conical ejection barrel 142. After the material is rectified by the guide plate 17, fine material smaller than the classified particle size can pass through the rotor blades 144 to form product and be discharged from the air outlet 16. Coarse material larger than the classified particle size is blocked by the rotor blades 144 and falls into the return hopper 19 through the gap between the rotor blades 144 and the guide plate 17. In addition, the conical ejection barrel 142 not only adjusts the wind field, but also prevents product sedimentation and accumulation there, allowing for the smooth discharge of qualified products.

[0030] Furthermore, the powder selection mechanism also includes a drive motor 29 disposed at the top of the cylinder 1, a reducer 210 connected to the output end of the drive motor 29, a driving pulley 11 connected to the reducer 210, a driven pulley 12 fixed to the outside of the rotating shaft 141, and a belt 13 connecting the driving pulley 11 and the driven pulley 12. The position of the drive motor 29 remains fixed to the position of the cylinder 1. The rotor cage 14 is driven independently by the drive motor 29. The direction and speed of the rotor cage 14 and the stirring shaft 4 are independent of each other. By adjusting the speed of the rotor cage 14, the classification particle size of the centrifugal classification zone where the rotor cage is located is adjusted, and the dynamic control of product fineness is more effective.

[0031] Furthermore, the rotating shaft 141 is connected to the stirring shaft 4 via a bearing, so that the rotating shaft 141 can rotate around the stirring shaft 4 .

[0032] Furthermore, the stirring spiral 5 has a double helix structure, which helps improve grinding efficiency and prevents uneven force during rotation, resulting in wobble. The helix angle is set to 10° to 30°, and the helix angles of the upper and lower parts of the spiral can be kept consistent or set differently. In addition, a wear-resistant lining is provided on the surface of the stirring spiral. The stirring spiral can also have a multi-helix structure, and the number of stirring shafts can be designed to be single-axis driven or symmetrically designed to be multi-axis driven.

[0033] Furthermore, a one-way air lock valve 8 is provided at the medium adding port 7. The medium ball is added through the medium adding port. The medium ball is a steel ball or a ceramic ball. The one-way air lock valve can ensure that the medium ball can enter the cylinder while the material and the air flow in the cylinder cannot overflow from here.

[0034] Furthermore, a drainage tube 20 is provided at the air outlet 16, a dust collecting device 21 is provided at the outlet of the drainage tube 20, and a fan 22 is provided on the air outlet pipe of the dust collecting device 21. The fan 22 is used to exhaust air inside the cylinder to form a negative pressure, which is convenient for air intake at the air inlet 15. The discharge port of the dust collecting device 21 is used to collect the qualified products finally obtained.

[0035] Example 2 See also Figures 1 to 4 A method for grinding and preparing new energy negative electrode materials using the device described in Example 1 comprises the following steps: S1. The medium balls are initially fed into the grinding zone at the bottom of the cylinder 1 through the medium inlet 7 according to a certain particle size distribution. The driving motor 2 drives the stirring shaft 4 to rotate through the reducer 3. The stirring screw 5 provided on the stirring shaft 4 drives the medium balls to perform high-speed circular motion and up and down motion along the cylinder 1. By adjusting the speed of the driving motor 2, and thereby adjusting the speed of the stirring shaft 4 and the linear speed of the stirring screw 5, the medium balls are controlled to maintain an appropriate movement speed, so that the device can fully exert its efficient grinding effect. S2. After the material has undergone the preliminary pre-crushing process, it is pressure-fed into the grinding zone at the lower part of the cylinder 1 by the feed screw 6. By adjusting the speed of the feed screw 6, the appropriate feed speed is maintained to control the feed amount to avoid insufficient or excessive feeding, which affects the output of the device and product quality. The material is crushed and fined under the high-speed collision, extrusion and friction grinding of the medium balls. The ground fine material gradually moves upward through the gaps between the medium balls and the lifting effect of the stirring screw 5 to the air inlet 15, forming a gas-solid mixing zone with the air fed from the outside. S3. The fan 22 behind the dust collecting device 21 exhausts air from the interior of the cylinder 1, forming a negative pressure inside the cylinder 1. Air enters through the air inlet 15 under the action of the negative pressure, is fully mixed with the ground fine material in the gas-solid mixing zone, and then drives the ground fine material upward. During the upward movement of the airflow, particles whose own gravity is greater than the buoyancy of the airflow fall back to the grinding zone at the bottom of the cylinder 1 to continue to be ground. The finer particles rise with the airflow, are rectified by the guide plate 17, and are further classified in the centrifugal classification zone where the rotor cage 14 is located. S4, the driving motor 29 drives the belt 13 through the reducer 2 10 to drive the rotor cage 14 to rotate, and the classification particle size is controlled by adjusting the speed of the rotor cage 14 and the flow of the fan 22. The coarser particles larger than the classification particle size are intercepted by the rotor cage 14, fall into the return hopper 19 through the gap between the rotor blades 144 and the guide plate 17, and fall back to the grinding area at the lower part of the cylinder 1 for further grinding. The finer materials smaller than the classification particle size are discharged from the air outlet 16 with the air flow and collected by the dust collecting device 21 to obtain the final qualified product.

[0036] During operation, system parameters such as feed screw speed, stirring shaft speed, fan air volume, and rotating shaft speed can be adjusted according to raw materials and system fluctuations to achieve the purpose of controlling product particle size indicators and stabilizing product quality. In addition, after the medium balls are worn, a certain amount of medium balls of the largest specification can be regularly replenished.

[0037] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention and are not limiting. Other modifications or equivalent substitutions made to the technical solution of the present invention by ordinary technicians in this field should be included in the scope of the claims of the present invention as long as they do not depart from the spirit and scope of the technical solution of the present invention.

Claims

1. A new energy negative electrode material grinding and pulverizing device, characterized in that: The invention comprises a barrel (1), a stirring mechanism and a powder selection mechanism, wherein a feeding screw (6), a medium adding port (7) and an air inlet (15) are arranged on the side wall of the barrel (1), wherein the feeding screw (6) is located at the lower end of the side wall, and the medium adding port (7) and the air inlet (15) are located at the upper end of the side wall; the stirring mechanism comprises a driving motor (2) and a stirring shaft (4), wherein the driving motor (2) is arranged at the top of the barrel and is used to provide power for the stirring shaft (4), and a stirring screw (5) is arranged on the stirring shaft (4), wherein the stirring screw (5) is located inside the barrel (1) and is located at the medium adding port (7). and below the air inlet (15); the powder selection mechanism includes a rotor cage (14) sleeved on the outside of the stirring shaft (4), the rotor cage (14) is located inside the cylinder (1) and above the air inlet (15), the top of the cylinder (1) is provided with an annular connecting plate (18) for blocking the top opening of the cylinder (1), the middle of the annular connecting plate (18) forms an air outlet (16), a plurality of guide plates (17) are provided in an annular array on the lower surface of the annular connecting plate (18), the guide plates (17) enclose the rotor cage (14), and a return hopper (19) is provided at the bottom of the guide plate (17).

2. The new energy negative electrode material grinding and pulverizing device according to claim 1, characterized in that: The return hopper (19) is in the shape of a truncated cone, with the large end opening facing upwards and fixed to the bottom of the guide plate (17), and the small end opening facing downwards, and the diameter thereof is larger than the diameter of the stirring shaft (4), and the stirring shaft (4) passes through the return hopper (19).

3. The new energy negative electrode material grinding and pulverizing device according to claim 1, characterized in that: The rotor cage (14) comprises a rotating shaft (141) sleeved on the outer circumference of the stirring shaft (4), a conical throwing barrel (142) arranged at the lower end of the rotating shaft (141), and a multi-layered annular frame (143) arranged outside the conical throwing barrel (142). Rotor blades (144) are arranged between the annular frames (143), and a fixing rod (145) is arranged between the annular frame (143) and the conical throwing barrel (142).

4. The new energy negative electrode material grinding and pulverizing device according to claim 3, characterized in that: The powder selection mechanism further includes a second drive motor (9) arranged on the top of the cylinder (1), a driving pulley (11) connected to the output end of the second drive motor (9), a driven pulley (12) arranged outside the rotating shaft (141), and a belt (13) connecting the driving pulley (11) and the driven pulley (12).

5. The new energy negative electrode material grinding and pulverizing device according to claim 4, characterized in that: The rotating shaft (141) is connected to the stirring shaft (4) via a bearing.

6. The new energy negative electrode material grinding and pulverizing device according to claim 1, characterized in that: The stirring screw (5) is a double helix structure or a multi-helix structure.

7. The new energy negative electrode material grinding and pulverizing device according to claim 1, characterized in that: The medium inlet (7) is provided with a one-way air lock valve (8).

8. The new energy negative electrode material grinding and pulverizing device according to any one of claims 1 to 7, characterized in that: A guide tube (20) is provided at the air outlet (16), a dust collecting device (21) is provided at the outlet of the guide tube (20), and a fan (22) is provided on the air outlet pipe of the dust collecting device (21).

9. A method for grinding and pulverizing new energy negative electrode materials using the device according to any one of claims 1 to 8, characterized in that: The steps include: S1, the medium balls are fed into the grinding area at the bottom of the cylinder (1) through the medium feeding port (7) according to a certain particle size distribution, the driving motor (2) drives the stirring shaft (4) to rotate, and the stirring screw (5) drives the medium balls to perform high-speed circular motion and up-and-down turning motion along the cylinder (1); S2. After the material has been pre-crushed, it is fed into the grinding zone at the bottom of the cylinder (1) by the feed screw (6) under pressure. It is crushed and fined under the high-speed collision, extrusion and friction grinding of the medium balls. The fine material after grinding gradually moves upward through the gap between the medium balls and the lifting effect of the stirring screw (5) to the air inlet (15), where it forms a gas-solid mixing zone with the air fed from the outside. S3, air enters from the air inlet (15), is fully mixed with the ground fine material in the gas-solid mixing zone, and then drives the ground fine material to move upward. During the upward movement of the airflow, the particles whose own gravity is greater than the buoyancy of the airflow fall back to the grinding zone at the bottom of the cylinder (1) to continue to be ground. The finer particles rise with the airflow, are rectified by the guide plate (17), and are classified in the centrifugal classification zone where the rotor cage (14) is located; S4. After being classified in the centrifugal classification zone, the coarser particles are intercepted by the rotor cage (14) and fall back into the grinding zone at the bottom of the cylinder (1) through the return hopper (19) to continue to be ground. The finer materials are discharged from the air outlet (16) along with the air flow and collected by the dust collecting device (21) to obtain the final qualified product.

10. The method for grinding and preparing new energy negative electrode materials according to claim 9, characterized in that: Step S4 specifically includes: The second driving motor (9) drives the belt (13) to drive the rotor cage (14) to rotate. The classification particle size is controlled by adjusting the rotation speed of the rotor cage (14). Coarser particles larger than the classification particle size are intercepted by the rotor cage (14), fall into the return hopper (19) through the gap between the rotor blade (144) and the guide plate (17), and fall back to the grinding area at the lower part of the cylinder (1) to continue grinding. Finer materials smaller than the classification particle size are discharged from the air outlet (16) along with the air flow and collected by the dust collecting device (21) to obtain the final qualified product.

Images