Aerodynamic force fine selection machine and battery pole piece fine selection process
By designing an aerodynamic separator, the efficient peeling and precise separation of battery electrodes are achieved through the use of vortex fields and blade shaft structures. This solves the problem of poor electrode separation performance in existing equipment, reduces production costs, and improves production efficiency.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-01-22
- Publication Date
- 2026-03-13
AI Technical Summary
Existing equipment is not effective in peeling and separating battery electrodes, and there is limited research on the application of air jet mills in peeling battery electrodes, making it impossible to achieve precise separation.
A pneumatic separation machine was designed, which uses nozzles to release airflow at a set pressure to form a vortex field. Combined with the blade shaft and reflux chamber structure, it can achieve efficient and precise separation of black powder and metal foil.
This technology enables efficient and precise separation of black powder and metal foil, reducing production costs and improving production efficiency.
Smart Images
Figure CN121663016A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the technical field of battery electrode recycling equipment, specifically to a pneumatic separator and a battery electrode separation process. Background Technology
[0002] The positive electrode of the battery is made of aluminum foil and materials such as ternary lithium and lithium iron phosphate, while the negative electrode is made of copper foil and graphite. During recycling, the metal foil and black powder need to be separated, and then the metal foil and black powder are recycled separately. Existing processing equipment, such as Chinese Patent 2022108503022, discloses a waste battery processing equipment and method. This waste battery processing equipment includes a hopper, a dry stripper, a graphite separator, an ultrafine separator, a carbon powder collector, a pulse dust collector, and a first induced draft fan arranged in sequence. The dry stripper includes a dry stripper shell, a stripping ring installed on the inner wall of the dry stripper shell, and several protruding teeth on the inner side of the stripping ring. A grinding disc driven by a main motor is rotatably connected inside the dry stripper shell. The grinding disc is located inside the stripping ring, and several stripping blocks are installed on the edge of the grinding disc. A first ultrasonic separator is connected to the lower end of the dry stripper shell, and a second ultrasonic separator is connected to the lower end of the ultrafine separator. This treatment method utilizes a combination of dry stripper, graphite separator, ultrafine separator, toner collector, and pulse dust collector.
[0003] The above technical solution uses a dry stripper to peel off the battery electrodes, but the peeling effect is poor and it requires the use of multiple separators.
[0004] In addition, existing airflow mills, such as Chinese Patent 2019205821794, disclose a jetting device for an airflow mill, including a grinding chamber. Multiple nozzles that can spray airflow into the grinding chamber are installed in a ring around the grinding chamber. The nozzles are characterized by having spray holes, which include an inlet section with a gradually decreasing diameter from the inlet to the inside of the spray hole and an outlet section with a gradually increasing diameter from the inside of the spray hole to the outlet. The outlet section is conical in shape.
[0005] The above technical solutions have the following disadvantages: 1. Existing air jet mills are mainly used for pulverization, and there is little research on their application in battery electrode stripping; 2. The discharge structure of existing air jet mills is not suitable for the products of battery electrode stripping, and it is impossible to refine the products of battery electrode stripping. Summary of the Invention
[0006] The purpose of this invention is to provide a pneumatic refining machine and a battery electrode refining process to address the above problems. By utilizing a pneumatic milling process, the battery electrode can be stripped and the stripped product can be refined simultaneously.
[0007] To achieve the above objectives, the present invention discloses a pneumatic separator, which includes a frame, an air mill chamber mounted on the frame, nozzles mounted on the side wall of the air mill chamber, a feeding device connected to the lower side of the air mill chamber, an upper discharge device connected to the upper end of the air mill chamber, a return pipe connected to the lower part of the air mill chamber, a blade shaft rotatably connected to the inner side of the return pipe and arranged along its axial direction, four semi-circular blades mounted on the side of the blade shaft and evenly arranged around the blade shaft, a blade shaft drive device for driving the blade shaft mounted on the outer side of the return pipe, a return chamber connected to the lower part of the return pipe, and a lower discharge device connected to the lower part of the return chamber.
[0008] In operation, firstly, the positive and negative electrode sheets of the battery are dried and then made into fragments of a predetermined size. Next, these battery electrode fragments are fed into the pneumatic separator described above. The nozzles release airflow at a predetermined pressure, creating a vortex field, and the blade shaft rotates at a uniform speed. Then, when the amount of material not completely separated in the return chamber exceeds a predetermined weight, the blade shaft stops rotating for a predetermined time, and the material in the upper part of the return chamber returns to the vortex separation zone for further separation. Finally, when the amount of cleanly separated metal foil in the return chamber exceeds a predetermined height, the discharge device is activated. This achieves efficient and precise separation of black powder and metal foil.
[0009] Preferably, the lower discharge device includes an upper butterfly valve, a lower discharge hopper connected to the lower part of the upper butterfly valve, a lower butterfly valve connected to the lower part of the lower discharge hopper, and a lower discharge port connected to the lower part of the lower butterfly valve.
[0010] When the stripped metal foil in the return chamber exceeds the set height, firstly, the upper butterfly valve is opened, allowing the stripped metal foil to fall into the lower discharge chamber under gravity. When the stripped metal foil in the lower discharge chamber exceeds the set height, the upper butterfly valve is closed to block airflow. Then, the lower butterfly valve is opened, allowing the stripped metal foil to be discharged through the lower discharge port. After discharge, first, the lower butterfly valve is closed, then the upper butterfly valve is opened to restore normal airflow, effectively preventing airflow leakage during discharge and ensuring stable pressure in the stripping zone.
[0011] Preferably, the reflux pipe has reflux pipe flanges at both the upper and lower ends, wherein one reflux pipe flange is connected to the air mill chamber, and the other reflux pipe flange is connected to the reflux chamber.
[0012] The reflux pipe structure is compact and easy to install, which helps reduce production costs.
[0013] Preferably, the return pipe is connected to a shaft sleeve through which the blade shaft passes, and the blade shaft drive device includes a blade motor mounted on the shaft sleeve.
[0014] In operation, the blade motor drives the blade shaft and blades to rotate, forming a trough between adjacent blades. Material falls into the trough under gravity and is carried into the return chamber as the trough rotates. The cooperation between the blades and the return pipe acts as an airlock, allowing for continuous, uniform, and quantitative unloading, ensuring a stable gas-solid ratio in the pneumatic conveying system. It combines unloading and airlocking functions, preventing wind or backflow from affecting equipment operation.
[0015] Preferably, the upper discharge device includes an upper discharge hopper, an upper discharge port on the side of the upper discharge hopper, a sorting motor installed on the upper part of the upper discharge hopper, and a sorting pipe located inside the air mill chamber connected to the sorting motor via a drive shaft. The sorting pipe has a sorting port on its side.
[0016] During use, the stripped black powder enters the sorting pipe and the upper discharge hopper through the sorting port, and is discharged from the upper discharge port, thus collecting the black powder.
[0017] Preferably, the air mill chamber includes a lower air mill chamber and an upper air mill chamber, with an end cover connected to the upper part of the upper air mill chamber.
[0018] This structure facilitates the manufacturing and assembly of the air mill chamber, which helps to improve production efficiency and reduce production costs.
[0019] Preferably, the feeding device includes a screw conveyor, with a feeding hopper connected to the upper part of the screw conveyor, and a feeding port connected to the screw conveyor is opened on the side of the air mill chamber.
[0020] During use, materials enter the air mill chamber through the feed hopper and screw conveyor, making it convenient to use.
[0021] Preferably, there are four nozzles, which are evenly arranged around the circumference of the air mill chamber.
[0022] When in use, the four nozzles work simultaneously, which helps to form a high-speed vortex field. The material collides violently in the vortex, completing the physical separation of black powder and metal foil.
[0023] Example 2: A battery electrode selection process, which includes the following steps: Step S1 involves drying the positive and negative electrode sheets of the battery and then forming them into fragments of a set size. In this step, the size of the battery electrode sheets is reduced to facilitate subsequent processing.
[0024] In step S2, the battery electrode fragments are fed into the pneumatic separator described above. The nozzles release airflow at a set pressure, creating a vortex field, and the blade shaft rotates at a constant speed. During this step, driven by compressed gas, the materials collide violently in the vortex, completing the physical separation of the black powder and metal foil. Specifically, the aluminum foil of the positive electrode and the black powder of ternary and lithium iron phosphate batteries, and the copper foil of the negative electrode and the graphite black powder, will exhibit different trajectories in the airflow field due to density differences. A trough is formed between adjacent blades, and the material falls into the trough under gravity and is carried into the return chamber as the trough rotates. Because the blades and the return pipe work together to lock the air, continuous, uniform, and quantitative unloading is possible, ensuring a stable gas-solid ratio in the pneumatic conveying system. This system combines unloading and air-locking functions, preventing wind or gas backflow from affecting equipment operation.
[0025] Step S3: When the amount of material that has not been completely stripped in the return chamber exceeds the set weight, the blade shaft stops rotating for a set time, the return chamber opens, and the material in the upper part of the return chamber returns to the vortex stripping zone to continue stripping. In this step, the material in the upper part of the return chamber returns to the vortex stripping zone under the action of airflow to continue stripping, thereby improving the stripping quality.
[0026] In step S4, when the cleaned metal foil in the return chamber is higher than the set height, the lower discharge device is activated. In this step, the cleaned metal foil, because its density is much greater than that of the black powder, will gradually sink to the bottom. The cleaned metal foil is discharged from the lower discharge device, while the black powder is discharged from the upper discharge device and enters the next device for collection. How the black powder is collected uses existing technology and will not be described in detail here.
[0027] Preferably, in step S1, the moisture content of the dried battery positive and negative electrode sheets is less than 1%, and the size of the fragments is set to 1-2 cm; In step S2, the set pressure of the airflow is 0.8-1.0 MPa, and the temperature inside the air mill chamber is less than 80°C. In step S3, the set time for opening the reflux chamber 3 is 1-2 seconds; In step S4, when the amount of black powder on the metal foil is less than 5% of the initial amount, it is considered to be completely removed.
[0028] In summary, the beneficial effects of this invention are as follows: In use, firstly, the positive and negative electrode sheets of the battery are dried and made into fragments of a predetermined size. Then, the battery electrode fragments are fed into the pneumatic separator described above. The nozzle releases airflow at a predetermined pressure, forming a vortex field, and the blade shaft rotates at a uniform speed. Next, when the amount of material not completely separated in the return chamber exceeds a predetermined weight, the blade shaft stops rotating for a predetermined time, and the material in the upper part of the return chamber returns to the vortex separation zone for further separation. Finally, when the amount of cleaned metal foil in the return chamber exceeds a predetermined height, the discharge device is activated. This achieves efficient and precise separation of black powder and metal foil. Attached Figure Description
[0029] Figure 1 This is a schematic diagram of the structure of a pneumatic air-purifying machine according to the present invention; Figure 2 This is a top view schematic diagram of the return pipe and blades in a pneumatic air separator according to the present invention; Figure 3 This is a three-dimensional structural diagram of the return pipe and blades in a pneumatic air separator according to the present invention; Figure 4 This is a three-dimensional structural diagram of the blade shaft and blades in a pneumatic air separator according to the present invention.
[0030] In the diagram: 1. Frame; 2. Lower air mill chamber; 3. Return chamber; 4. Lower discharge chamber; 5. Lower discharge port; 6. Upper air mill chamber; 7. Upper discharge chamber; 8. Upper discharge port; 9. Screw conveyor; 10. Feed hopper; 11. Feed inlet; 12. End cover; 13. Sorting pipe; 14. Sorting port; 15. Sorting motor; 16. Drive shaft; 17. Nozzle; 18. Return pipe; 19. Upper butterfly valve; 20. Lower butterfly valve; 21. Return pipe flange; 22. Rotary shaft sleeve; 23. Blade shaft; 24. Blade; 25. Blade motor. Detailed Implementation
[0031] The specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings and examples. The following examples are for illustrative purposes only and are not intended to limit the scope of the invention.
[0032] Example 1, as Figures 1 to 4 As shown, a pneumatic separator includes a frame 1, on which an air mill chamber is mounted. Nozzles 17 are mounted on the side wall of the air mill chamber. A feeding device is connected to the lower side of the air mill chamber, and an upper discharge device is connected to the upper end of the air mill chamber. A return pipe 18 is connected to the lower part of the air mill chamber. A blade shaft 23, rotatably connected along the axial direction of the return pipe 18, is rotatably connected to the inner side of the return pipe 18. Four semi-circular blades 24 are mounted on the side of the blade shaft 23, and the four blades 24 are evenly arranged circumferentially along the blade shaft 23. A blade shaft drive device for driving the blade shaft 23 is mounted on the outer side of the return pipe 18. A return chamber 3 is connected to the lower part of the return pipe 18, and a lower discharge device is connected to the lower part of the return chamber 3. In use, firstly, the positive and negative electrode sheets of a battery are dried and made into fragments of a predetermined size. Then, the battery electrode fragments are fed into the pneumatic separator as described above. The nozzles 17 release airflow at a predetermined pressure, forming a vortex field, and the blade shaft 23 rotates at a uniform speed. Then, when the amount of material not completely separated in the return chamber 3 exceeds the set weight, the blade shaft 23 stops rotating for a set time, and the material in the upper part of the return chamber 3 returns to the vortex stripping zone to continue stripping. Finally, when the amount of cleanly stripped metal foil in the return chamber 3 exceeds the set height, the discharge device is activated. This achieves efficient and precise separation of black powder and metal foil.
[0033] Specifically, the lower discharge device includes an upper butterfly valve 19, with a lower discharge bin 4 connected to the lower part of the upper butterfly valve 19. A lower butterfly valve 20 is connected to the lower part of the lower discharge bin 4, and a lower discharge port 5 is connected to the lower part of the lower butterfly valve 20. When the stripped metal foil in the return chamber 3 is higher than the set height, firstly, the upper butterfly valve 19 is opened, and the stripped metal foil falls into the lower discharge bin 4 under gravity. When the stripped metal foil in the lower discharge bin 4 is higher than the set height, the upper butterfly valve 19 is closed to block the airflow. Then, the lower butterfly valve 20 is opened, and the stripped metal foil is discharged through the lower discharge port 5. After discharge, firstly, the lower butterfly valve 20 is closed, and then the upper butterfly valve 19 is opened to restore normal airflow, effectively preventing airflow leakage during discharge and ensuring stable pressure in the stripping zone.
[0034] Specifically, the return pipe 18 has return pipe flanges 21 at both ends. One return pipe flange 21 is connected to the air mill chamber, and the other return pipe flange 21 is connected to the return chamber 3. This structure of the return pipe 18 is compact, easy to install, and helps reduce production costs. The return pipe 18 is connected to a shaft sleeve 22 through which the blade shaft 23 passes. The blade shaft drive device includes a blade motor 25 mounted on the shaft sleeve 22. In use, the blade motor 25 drives the blade shaft 23 and blades 24 to rotate. A trough is formed between two adjacent blades 24. The material falls into the trough under gravity and is carried into the return chamber 3 as the trough rotates. Because the blades 24 and the return pipe 18 cooperate to lock the air, the material can be discharged continuously, evenly, and quantitatively, ensuring a stable gas-solid ratio in the pneumatic conveying system. It has the dual functions of discharging and locking the air, preventing wind or backflow of gas from affecting the operation of the equipment.
[0035] like Figure 1 As shown, the upper discharge device includes an upper discharge bin 7, with an upper discharge port 8 on its side. A sorting motor 15 is installed on the upper part of the upper discharge bin 7. The sorting motor 15 is connected to a sorting pipe 13 located inside the air mill chamber via a drive shaft 16. The sorting pipe 13 has a sorting port 14 on its side. Preferably, a filter screen is installed on the sorting port 14. The filter screen adopts existing technology and will not be described in detail here. In use, the stripped black powder enters the sorting pipe 13 and the upper discharge bin 7 through the sorting port 14 and is discharged from the upper discharge port 8, thus collecting the black powder. The air mill chamber includes a lower air mill chamber 2 and an upper air mill chamber 6. An end cover 12 is connected to the upper part of the upper air mill chamber 6. Specifically, the lower air mill chamber 2 and the upper air mill chamber 6 are connected by a flange structure, and the upper air mill chamber 6 is connected to the end cover 12 by a flange structure. This structure facilitates the manufacturing and assembly of the air mill chamber, which helps to improve production efficiency and reduce production costs.
[0036] Specifically, the feeding device includes a screw conveyor 9, with a feeding hopper 10 connected to the upper part of the screw conveyor 9. A feeding port 11, connected to the screw conveyor 9, is located on the side of the air mill chamber. In use, the material enters the air mill chamber through the feeding hopper 10 and the screw conveyor 9, making it convenient to use. There are four nozzles 17, evenly arranged around the circumference of the air mill chamber. During use, the four nozzles 17 operate simultaneously, which helps to form a high-speed vortex field. The material undergoes violent collisions within the vortex, completing the physical separation of the black powder and the metal foil.
[0037] Example 2, a battery electrode selection process, includes the following steps: Step S1 involves drying the positive and negative battery electrodes and then forming them into fragments of a predetermined size. Specifically, in step S1, the moisture content of the dried battery electrodes is less than 1%, and the predetermined size of the fragments is 1-2 cm. Preferably, the size of the fragments is 1 x 1 cm, 1 x 2 cm, or 2 x 2 cm. Reducing the size of the battery electrodes in this step facilitates subsequent processing.
[0038] In step S2, the battery electrode fragments are fed into the pneumatic grinding machine as described above. Nozzle 17 releases airflow at a set pressure, forming a vortex field, and the blade shaft 23 rotates at a uniform speed. Specifically, in step S2, the set pressure of the airflow is 0.8-1.0 MPa, and the temperature inside the grinding chamber is less than 80°C. Preferably, the airflow pressure is 0.8 MPa, 0.9 MPa, or 1.0 MPa, and the temperature inside the grinding chamber is 70°C, 75°C, or 80°C. In this step, driven by compressed gas, the material undergoes violent collisions in the vortex, completing the physical separation of the black powder and metal foil. Specifically, the aluminum foil of the positive electrode and the black powder of ternary lithium iron phosphate, and the copper foil of the negative electrode and the graphite black powder will exhibit different trajectories in the airflow field due to density differences. A trough is formed between adjacent blades 24, and the material falls into the trough under gravity and is carried into the return chamber 3 as the trough rotates. Because the blades 24 and the return pipe 18 cooperate to lock the air, continuous, uniform, and quantitative unloading is possible, ensuring a stable gas-solid ratio in the pneumatic conveying system. This system combines unloading and air-locking functions, preventing wind or gas backflow from affecting equipment operation.
[0039] In step S3, when the amount of material not completely stripped in the return chamber 3 exceeds a set weight, the blade shaft 23 stops rotating for a set time, the return chamber 3 opens, and the material in the upper part of the return chamber 3 returns to the vortex stripping zone for further stripping. Specifically, in step S3, the set time for opening the return chamber 3 is 1-2 seconds. Preferably, the opening time of the return chamber 3 is 1, 1.5, or 2 seconds. In this step, the material in the upper part of the return chamber 3 returns to the vortex stripping zone under the action of airflow to continue stripping, improving the stripping quality.
[0040] In step S4, when the cleaned metal foil in the return chamber 3 is higher than the set height, the lower discharge device is activated. In steps S3 and S4, when the weight of the black powder on the metal foil is less than 5% of the initial amount, it is considered that the metal foil has been cleaned. In this step, the cleaned metal foil, because its density is much greater than that of the black powder, will gradually settle to the bottom. The cleaned metal foil is discharged from the lower discharge device, while the black powder is discharged from the upper discharge device and enters the next device for collection. How the black powder is collected uses existing technology and will not be described in detail here.
[0041] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and substitutions can be made without departing from the technical principles of the present invention, and these improvements and substitutions should also be considered within the scope of protection of the present invention.
Claims
1. A pneumatic fine-grained separator, comprising a frame (1), an air mill chamber mounted on the frame (1), nozzles (17) mounted on the side wall of the air mill chamber, a feeding device connected to the lower side of the air mill chamber, and an upper discharge device connected to the upper end of the air mill chamber, characterized in that, The lower part of the air mill chamber is connected to a return pipe (18). Inside the return pipe (18) is a blade shaft (23) arranged along its axial direction. Four semi-circular blades (24) are installed on the side of the blade shaft (23). The four blades (24) are evenly arranged around the blade shaft (23). A blade shaft drive device for driving the blade shaft (23) is installed on the outside of the return pipe (18). The lower part of the return pipe (18) is connected to a return chamber (3). The lower part of the return chamber (3) is connected to a discharge device.
2. The pneumatic air-purifying machine as described in claim 1, characterized in that, The lower discharge device includes an upper butterfly valve (19), the lower part of which is connected to a lower discharge hopper (4), the lower part of which is connected to a lower butterfly valve (20), and the lower part of which is connected to a lower discharge port (5).
3. The pneumatic refining machine as described in claim 2, characterized in that, The reflux pipe (18) has reflux pipe flanges (21) at both the upper and lower ends. One reflux pipe flange (21) is connected to the air mill chamber, and the other reflux pipe flange (21) is connected to the reflux chamber (3).
4. The pneumatic air-purifying machine as described in claim 1, characterized in that, The return pipe (18) is connected to a shaft sleeve (22) through which the blade shaft (23) passes. The blade shaft drive device includes a blade motor (25) mounted on the shaft sleeve (22).
5. The pneumatic refining machine as described in any one of claims 1 to 4, characterized in that, The upper discharge device includes an upper discharge hopper (7) installed on the upper discharge hopper (7), an upper discharge port (8) on the side of the upper discharge hopper (7), a sorting motor (15) installed on the upper part of the upper discharge hopper (7), and a sorting pipe (13) located inside the air mill chamber connected to the sorting motor (15) through a drive shaft (16). The sorting pipe (13) has a sorting port (14) on the side.
6. The pneumatic refining machine as described in any one of claims 1 to 4, characterized in that, The air mill chamber includes a lower air mill chamber (2) and an upper air mill chamber (6), with an end cap (12) connected to the upper part of the upper air mill chamber (6).
7. The pneumatic refining machine as described in any one of claims 1 to 4, characterized in that, The feeding device includes a screw conveyor (9), with a feeding hopper (10) connected to the upper part of the screw conveyor (9), and a feeding port (11) connected to the screw conveyor (9) is opened on the side of the air mill chamber.
8. The pneumatic refining machine as described in any one of claims 1 to 4, characterized in that, The number of nozzles (17) is four, and the four nozzles (17) are evenly arranged around the circumference of the air mill chamber.
9. A process for selecting battery electrode sheets, characterized in that, Includes the following steps: Step S1: Dry the positive and negative electrode plates of the battery and then make them into fragments of a set size; Step S2: The battery electrode fragments are fed into the pneumatic sorting machine as described in any one of claims 1 to 4. The nozzle (17) releases the airflow at a set pressure to form a vortex field, and the blade shaft (23) rotates at a constant speed. Step S3: When the amount of material that has not been completely stripped in the return chamber (3) is greater than the set weight, the blade shaft (23) stops rotating for a set time, the return chamber (3) is opened, and the material in the upper part of the return chamber (3) returns to the vortex stripping zone to continue stripping. Step S4: When the cleaned metal foil in the return chamber (3) is higher than the set height, start the discharge device.
10. The battery electrode selection process as described in claim 9, characterized in that, In step S1, the moisture content of the dried battery positive and negative electrode sheets is less than 1%, and the size of the fragments is set to 1-2 cm. In step S2, the set pressure of the airflow is 0.8-1.0 MPa, and the temperature inside the air mill chamber is less than 80°C. In step S3, the set time for opening the reflux chamber 3 is 1-2 seconds; In step S4, when the amount of black powder on the metal foil is less than 5% of the initial amount, it is considered to be completely removed.