An electrode washing stripping and recycling process without liquid injection and production line

Abstract

The application discloses a kind of unliquid-filled electrode water washing stripping recovery process and production line, it is related to unliquid-filled electrode recovery field, solve traditional mechanical grinding recovery black powder low purity, high energy consumption, low recovery rate and other problems.Process includes cutting unliquid-filled electrode, by 50 DEG C ~ 80 DEG C hot water immersion stirring to make black powder separate, screen hole separates black powder and current collector, current collector is deeply cleaned and then is pressed block recovery, black powder slurry is filtered, dried, and the separation and recovery of black powder and current collector are completed.Production line contains drum stripping machine, deep cleaning machine and other equipment, drum stripping machine is equipped with stripping area and screening area, cooperate with buffer baffle and scoop to realize efficient stripping, also provided with high-temperature tail gas generated in subsequent processing process is used to heat circulating water, realize heat recovery.The application greatly reduces the content of aluminum / copper and magnetic impurities in black powder, the aluminum content can be less than 500ppm, improves the recovery rate and quality of black powder, and the energy consumption is lower, and the recovered black powder can reach commercial grade and be directly used for battery production.

Description

Technical Field

[0001] This invention relates to the field of unfilled electrode current collectors and black powder stripping and recycling, and particularly to a water washing stripping and recycling process and production line for unfilled electrodes. Background Technology

[0002] Lithium-ion batteries have become the dominant product in the current power battery field. The unfilled electrode of a lithium-ion battery consists of a layer of black powder coated on the current collector. This black powder contains nickel, cobalt, lithium, iron, graphite, etc., and has recycling value. The positive electrode current collector is generally made of aluminum foil. However, pure aluminum foil is prone to oxidation, forming a dense oxide layer that significantly reduces conductivity. Therefore, in actual processing, the aluminum foil is usually first carbon-coated, encapsulating a layer of carbon atoms on its surface to isolate it from external oxygen and increase conductivity. Carbon coating typically uses water-based acrylic resin or water-based polyurethane as a binder to adhere the conductive carbon powder to the aluminum foil surface. Simultaneously, the smooth surface of pure aluminum has poor wettability with PVDF slurry, resulting in poor adhesion when black powder is coated onto the aluminum foil later. After carbon coating, PVDF can form good contact with the porous conductive carbon layer, making it easier for the black powder slurry to anchor onto the carbon layer surface, thus improving the adhesion strength between the black powder coating and the current collector.

[0003] In the lithium battery production process, waste products may be generated at each stage. For battery electrodes, the production process includes coating black powder on the current collector, then winding it into a cell, assembling the casing, and then injecting electrolyte. Quality inspection is arranged after each stage. If quality problems are found during the quality inspection, the batch of products will be scrapped. Electrodes before electrolyte injection are called un-injected electrodes in the industry. Since they have not yet come into contact with electrolyte, there are fewer substances that need to be separated in the recycling process. Theoretically, the black powder recovered from un-injected electrodes is of better quality.

[0004] Currently, there is no customized recycling equipment specifically for these unfilled electrode products in the industry. Recycling mainly relies on general-purpose equipment for recycling used batteries. This involves mechanically shredding the unfilled electrodes and then mechanically grinding them to separate the current collector from the black powder. Traditional processes have the following problems: 1. Mechanical grinding and stripping machines, when processing electrodes that have not been injected with liquid, will grind a small amount of aluminum foil into powder, which will be mixed into the lithium iron phosphate black powder, thereby increasing the aluminum content of the black powder and reducing its quality. At present, the aluminum content of the black powder obtained by mechanical grinding and stripping is about 500ppm to 1000ppm, and it is difficult to reach below 500ppm. The reason why the aluminum content in lithium iron phosphate materials needs to be strictly controlled is mainly because it is an inert impurity that directly damages the electrochemical performance of the material, leading to battery capacity decay and shortened life.

[0005] Aluminum is inert in electrochemical systems and does not participate in energy storage reactions. Its presence reduces the proportion of active material, directly leading to a significant decrease in the battery's discharge specific capacity. Furthermore, aluminum impurities hinder the normal insertion and extraction of lithium ions, increasing the battery's internal resistance and affecting rate performance.

[0006] Aluminum can damage the material structure: During production processes such as high-temperature sintering, aluminum impurities may enter the lithium iron phosphate lattice or react with it, generating non-electrochemically active impurity phases (such as Al2O3 or aluminum phosphate). This can damage the material's crystal structure, further reducing its cycle stability and lifespan.

[0007] Therefore, the power battery industry has strict restrictions on aluminum content. Complex aluminum removal processes must be used to reduce the aluminum content in the black powder to below 500 ppm in order to reduce the adverse effects on subsequent battery performance.

[0008] When processing the negative electrode that has not been filled with liquid, a small amount of copper foil is ground into powder. The copper powder mixes with the graphite powder, making it difficult to economically separate the copper metal. Although this does not affect the quality of the battery like aluminum does, it will directly lead to economic losses.

[0009] 2. The introduction of magnetic impurities during the mechanical grinding and stripping process is unavoidable. The content of magnetic foreign matter in lithium iron phosphate materials is controlled at extremely low levels to ensure absolute battery safety. Magnetic foreign matter (such as Fe, Ni, Cr, etc.) poses a significant threat to battery safety. Its harmful pathways are: magnetic foreign matter contamination, dissolution during battery charging, migration to the negative electrode and reduction to metal dendrites, piercing the separator, leading to internal short circuits, thermal runaway, or even fire and explosion. Therefore, its content must be controlled at extremely low levels (the standard for power-type materials requires magnetic foreign matter ≤3ppm). However, traditional mechanical grinding and stripping processes, due to high-speed grinding and pneumatic conveying, make it difficult to control the introduction of magnetic foreign matter. Even with the recent adoption of ceramic coating or ETFE spraying for protection, some areas cannot be protected, and magnetic foreign matter will still be introduced, leading to a decline in the quality of the black powder and causing inconvenience for subsequent processing.

[0010] 3. The traditional recycling method involves colliding the shredded, unfilled electrodes with each other and separating them through purely mechanical collision. However, during the crushing and impact process, the aluminum and copper foils may clump together, trapping the black powder adhering to their surfaces within the clumps. This results in a low recovery rate for the black powder, which is currently only around 80% in the industry and is difficult to improve further.

[0011] Therefore, a new process is needed for the recovery of electrodes that have not been filled with liquid. Summary of the Invention

[0012] The purpose of this invention is to provide a new process for the water washing, stripping, and recycling of unfilled electrodes, in order to improve or solve the technical problems existing in the prior art as described above.

[0013] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows: A process for the water washing, stripping, and recycling of unfilled electrodes includes the following steps: S1. Cut the unfilled electrode into sheets for easy insertion into subsequent equipment; S2. A water washing process is used to soak the unfilled electrode while stirring it, so that the black powder attached to the current collector is detached in one piece. S3. The black powder and the current collector are separated through the sieve holes. The black powder that is separated in whole pieces will be broken up by the impact of water during the stirring process. It can then pass through the sieve holes to form a black powder slurry. The current collector is intercepted by the sieve holes and continues to be transported forward. S4. The separated current collector enters the deep cleaning machine for deep cleaning. The cleaned slurry is then incorporated into the black powder slurry. The cleaned current collector is then compressed into briquettes for recycling. S5. The black powder slurry is dried to remove moisture, thus completing the separation and recycling of black powder and the current collector.

[0014] Furthermore, after step S4 and before S5, a fine filtration stage is provided to finely filter the black powder slurry and remove any present collector debris. This is because some collector debris may have passed through the sieve holes in the previous steps; the fine filtration stage can intercept this debris and prevent it from being mixed into the black powder.

[0015] Furthermore, the fine filtration stage employs a microporous filter with a pore size of 0.15mm to 0.2mm.

[0016] Furthermore, in step S2, the water washing process involves immersing the unfilled electrodes in water at 50°C to 80°C, and using equipment to lift and release the unfilled electrodes so that they fall. Through the mutual friction and impact of the falling electrodes, the black powder and the current collector are separated.

[0017] Compared with the prior art, the present invention has the following technical effects: Immersing the unfilled electrode in water at 50℃~80℃ with stirring can break the adhesion between the black powder and the current collector. Higher water temperatures result in higher peeling efficiency. Because there is no strong stirring or collision during the process, the current collector maintains its integrity, significantly reducing the likelihood of it being ground into powder. This reduces the aluminum or copper content in the recycled black powder, keeping the aluminum content below 500ppm. Furthermore, the absence of high-speed rotation and collisions significantly decreases the probability of magnetic materials being introduced, further improving the quality of the recycled black powder.

[0018] PVDF binder itself is insoluble in water. The reason why hot water soaking can remove the black powder from the aluminum foil surface is that during the washing process, the 50-80℃ warm water does not dissolve the PVDF binder inside the coating. Instead, water molecules penetrate into the interface between the aluminum substrate and the conductive carbon coating layer, weakening the interfacial bonding force between the aluminum foil and the carbon coating layer. The interfacial bonding force between the aluminum substrate and the carbon coating of the carbon-coated aluminum foil is not a covalent bond, but rather relies on physical adsorption and weak interfacial forces. Therefore, after water molecules penetrate into this interfacial layer, they can significantly weaken its bonding force. Combined with the relatively gentle stirring and the mechanical action from the drop impact, the conductive carbon coating layer, along with the black powder and PVDF binder attached to it, is peeled off from the aluminum substrate surface as a whole. In other words, in this solution, the peeling interface is located between the aluminum substrate and the carbon coating layer, not between the black powder coating and the carbon layer. Therefore, it is possible to remove the powder from the entire piece without dissolving the PVDF.

[0019] The present invention also provides a production line for the water washing, stripping and recycling of unfilled electrodes, for realizing the above-mentioned water washing, stripping and recycling process of unfilled electrodes, including a rotary drum stripper, a deep cleaning machine, a concentration and filtration combined centrifuge and a circulating water system; The rotary drum stripper is used to implement the water washing process, and the deep cleaning machine is used to deeply clean the collector after the initial stripping, further recovering the black powder that may remain on it and improving the recycling rate. The concentration and filtration combined centrifuge is used to separate black powder slurry and water. The black powder discharged from the concentration and filtration combined centrifuge has a water content between 22% and 25%. The black powder discharged from the concentration and filtration centrifuge is further dried by a drying system to remove moisture, reducing the moisture content to below 2%, before undergoing subsequent solid-phase remediation processing.

[0020] The drying system includes a feeding system, a hot air system, a drying tower, a product collection and dust removal system.

[0021] Fresh air is directly heated by the combustion of natural gas and then enters the drying tower at high speed through the air inlet volute at the bottom of the drying tower under the action of the blower.

[0022] The material to be dried is conveyed into the drying tower by a screw conveyor. After being agitated by the bottom dispersing device, it comes into full contact with the high-speed rotating hot air. The dried powdery material is carried upwards by the hot air, while the material that cannot be carried away falls to the bottom of the drying tower and is further broken up by the bottom crushing device. The material is rapidly dispersed, and the contact area between the material and the hot air increases rapidly. Under the action of centrifugal force, the product that has reached the required degree of dryness and fineness is blown out to the subsequent grading device. The material is rapidly dried in this process.

[0023] The dried black powder is mixed with the exhaust gas and discharged. The dried black powder is recovered by a bag filter, while the humid exhaust gas is further removed by a wet scrubber through an induced draft fan before being discharged into the atmosphere. The exhaust gas emissions meet the relevant emission standards.

[0024] The circulating water system is used to provide water at 50℃~80℃ required for the washing process, replenish water in a timely manner, and precipitate and remove colloids in the water. The circulating water system is insulated throughout to prevent heat loss.

[0025] Preferably, the rotary drum peeler includes a frame, a cylinder, a feeding device, a roller device, a discharge cylinder, and a drive mechanism, wherein the cylinder is rotatably mounted on the frame; The feeding device is fixedly mounted on the frame, and the feeding device is provided with an electrode feeding port and a water pipe inlet; The cylinder and the feeding device are rotatably connected together via a sealing element; the cylinder is divided into a stripping zone and a screening zone; Several lifting plates are provided along the axial direction on the inner wall of the stripping zone, which are used to lift the unfilled electrode located in the stripping zone to a certain height to obtain a better stirring effect. The inner wall of the screening zone is provided with several sieve holes for separating the slurry mixed with black powder from the collecting fluid; the end of the stripping zone is provided with a discharge scraper. The end plate at the junction of the stripping zone and the screening zone is provided with a discharge port, and one end of the discharge scraper is connected to the discharge port; The discharge cylinder is fixedly mounted on the frame and sleeved around the outer periphery of the screening section of the cylinder body, for guiding the screened slurry. The drive mechanism is used to drive the cylinder to rotate around the axis.

[0026] Furthermore, the rotary drum peeling machine also includes an angle adjustment mechanism, on which the machine frame is mounted, and the angle adjustment mechanism is used to adjust the tilt angle of the drum body.

[0027] Furthermore, the discharge cylinder of the rotary drum peeler is equipped with a water spray pipe located above the cylinder body for rinsing the outer surface of the cylinder body.

[0028] Furthermore, a first buffer ring is provided between the stripping zone and the screening zone. The first buffer ring has a notch for buffering and guiding the material entering the screening zone from the stripping zone. At least one second buffer ring is provided in the stripping zone. Among the adjacent second buffer rings, the height of the second buffer ring closer to the feed inlet is greater than the height of the second buffer ring closer to the discharge outlet.

[0029] Furthermore, each of the second buffer rings is provided with a discharge spoon near the feed inlet side. The discharge spoon extends smoothly from the inner wall of the cylinder to the top of the second buffer ring and is inclined toward the discharge outlet side.

[0030] The water-washing stripping system of this production line is divided into a stripping zone and a screening zone. A lifting plate is installed in the stripping zone. By inserting appropriately sized, un-liquid-filled electrodes into the cylinder and circulating hot water, the lifting plate thoroughly stirs and lifts the electrodes. Utilizing the impact of the water flow and the interaction between the electrodes, the black powder adhering to the surface of the current collector is effectively stripped off. This process is much gentler and milder than traditional mechanical stripping, avoiding the problem of the metal current collector tangling and entraining black powder, significantly improving the stripping efficiency and recovery rate of black powder. Simultaneously, the sieve holes in the screening zone can promptly separate the slurry mixed with black powder, which is then guided and collected through the discharge cylinder. The current collector is discharged through an arc-shaped guide plate, achieving effective separation of black powder and current collector. This helps improve the efficiency of subsequent black powder purification processes and the final purity of the black powder, providing strong support for meeting the industry's demand for high-purity black powder in large-scale production. Attached Figure Description

[0031] Figure 1 This is a flowchart of the production line for the water washing, stripping, and recycling of unfilled electrodes; Figure 2 This is a schematic diagram of the overall structure of the rotary drum peeler in the embodiment; Figure 3 This is a schematic diagram of the cylinder section of the rotary drum peeler in the embodiment; Figure 4 yes Figure 3 Sectional view along line AA; Figure 5 yes Figure 3 Sectional view along the BB direction; Figure 6 yes Figure 3 C-axis sectional view; Figure 7 yes Figure 3 Sectional view along the DD direction; Figure 8 yes Figure 3 EE-directed sectional view; Figure 9 yes Figure 5 Enlarged view of the X-axis position; Figure 10 yes Figure 7 Enlarged view of the Y-position in the middle; Figure 11 This is a schematic diagram of the overall three-dimensional structure of the rotary drum peeler in the embodiment.

[0032] The following is a list of component names represented by the reference numerals in the attached diagram: 1. Frame; 2. Cylinder; 3. Feeding device; 5. Discharge cylinder; 6. Drive mechanism; 7. Hinge shaft; 8. Angle adjustment mechanism; 9. Electrode feeding port; 10. Water inlet; 11. Stripping zone; 12. Screening zone; 13. Lifting plate; 14. Guide plate; 15. Discharge scraper; 16. Water spray pipe; 17. First second buffer ring; 18. Second second buffer ring; 19. Third second buffer ring; 20. First buffer ring; 21. Discharge port; 22. Discharge scoop; 23. Idler roller device; 100. Rotary drum peeler; 200. Deep cleaning machine; 300. Concentration and filtration combined centrifuge; 400. Graphene heat exchanger; 500. Circulating water tank. Detailed Implementation

[0033] The principles and features of the present invention are described below with reference to the accompanying drawings. The examples given are only for explaining the present invention and are not intended to limit the scope of the present invention.

[0034] Please refer to Figure 1 The diagram shows a flowchart of the un-liquid-injected electrode water washing stripping and recycling production line of the present invention. The un-liquid-injected electrode water washing stripping and recycling process and production line include: a rotary drum stripper 100, a deep cleaning machine 200, a concentration and filtration combined centrifuge 300, a graphene heat exchanger 400, a circulating water tank 500, and related connecting pipelines.

[0035] The rotary drum stripper 100 is used to implement the water washing process, so as to separate the current collector and black powder of the un-injected electrode, and output the black powder slurry and the separated current collector. The deep cleaning machine 200 is used to deeply clean the collector after preliminary stripping. It uses a more intense rotation speed and water flow than the drum separator to exert a stronger impact on the collector after preliminary stripping, so as to remove any black powder that may remain on the collector and improve the black powder recovery rate. The concentration and filtration combined centrifuge 300 is used to separate black powder slurry into black powder and water. It adopts the LWLZ type cantilever concentration and filtration combined centrifuge 300 of Suzhou Hanhao, which has the functions of concentration filtration and dewatering. The black powder discharged from the concentration and filtration combined centrifuge 300 has a water content between 22% and 25%. Subsequently, flash evaporation can be used to further remove water, so as to achieve the separation and recovery of black powder and collector.

[0036] The water separated by the concentration and filtration centrifuge 300 is returned to the circulating water tank 500. The circulating water tank 500 is used to provide water at 50℃~80℃ required for the washing process, to replenish water in a timely manner, and to settle and remove colloids in the water. The circulating water system is insulated throughout to prevent heat loss.

[0037] The graphene heat exchanger 400 is used to heat the circulating water using the high-temperature exhaust gas generated during the calcination process, thereby recovering the heat from the calcination process.

[0038] Please see Figure 2 and Figure 11 As shown, the rotary drum peeling machine 100 includes a frame 1, a cylinder 2, a feeding device 3, an end plate, a discharge cylinder 5, and a drive mechanism 6. The cylinder 2 is rotatably mounted on the frame 1. The feeding device 3 is fixedly installed on the frame 1, and the feeding device 3 is provided with an electrode feeding port 9 and a water pipe inlet 10; The cylinder 2 and the feeding device 3 are rotatably connected by a sealing element; the cylinder 2 is divided into a stripping zone 11 and a screening zone 12. The inner wall of the stripping zone 11 is provided with several lifting plates 13 along the axial direction, which are used to lift the unfilled electrodes in the stripping zone 11 to a certain height, thereby obtaining a better stirring effect. The inner wall of the screening zone 12 is provided with a number of sieve holes for separating the slurry mixed with black powder from the collecting fluid; the end of the stripping zone 11 is provided with a discharge scraper 15; The end plate at the junction of the stripping zone 11 and the screening zone 12 is provided with a discharge port 21, and one end of the discharge scraper 15 is connected to the discharge port 21. The discharge cylinder 5 is fixedly installed on the frame 1 and sleeved around the screening section 12 of the cylinder body 2 to guide the screened slurry. The drive mechanism 6 is used to drive the cylinder 2 to rotate along the axis under the support of the roller device 23.

[0039] It also includes an angle adjustment mechanism 8, which is mounted on the foundation, such as... Figure 2 As shown, the left side of the frame 1 is mounted on the angle adjustment mechanism 8, while the right side is mounted on the foundation via the hinge shaft 7. Thus, the angle adjustment mechanism 8 can adjust the rotation of the cylinder 2 around the hinge shaft 7, thereby changing the tilt angle of the entire cylinder 2.

[0040] The guide plate 14 of the screening section 12 is arc-shaped and is inclined along the circumference on the inner wall of the screening section 12.

[0041] The discharge cylinder 5 is equipped with a water spray pipe 16 located above the cylinder body 2, which is used to rinse the outer surface of the cylinder body 2 and prevent the black powder slurry from adhering to the surface of the cylinder body 2.

[0042] like Figure 3As shown, the stripping zone 11 is further divided into several partitions, and a second buffer ring is provided between adjacent partitions. In this example, there are three second buffer rings in total. From the feed inlet to the discharge outlet 21, they are the first second buffer ring 17, the second second buffer ring 18, and the third second buffer ring 19. Among the adjacent second buffer rings, the height of the second buffer ring closer to the feed inlet is greater than the height of the second buffer ring closer to the discharge outlet 21.

[0043] like Figure 4 , Figure 5 , Figure 6 and Figure 9 As shown, each of the second buffer rings is provided with a discharge spoon 22 near the feed inlet. The discharge spoon 22 extends smoothly from the inner wall of the cylinder 2 to the top of the second buffer ring and is inclined toward the discharge outlet 21.

[0044] like Figure 10 As shown, the end of the copy plate 13 is designed with a rounded shape.

[0045] like Figure 7 As shown, a first buffer ring 20 is provided between the stripping zone 11 and the screening zone 12. The first buffer ring 20 has a notch for buffering and guiding the material entering the screening zone 12 from the stripping zone 11.

[0046] refer to Figure 8 As shown, the discharge port 21 is eccentrically positioned.

[0047] Its working process is as follows: Unfilled electrodes, cut to the appropriate size, are fed into the drum 2 of the rotary drum peeler 100 through the electrode feeding port 9. Simultaneously, hot water at 50℃~80℃ is introduced into the drum 2 through the water inlet 10. The drive mechanism 6 drives the drum 2 to rotate along its axis. The lifting plates 13 located on the inner wall of the peeling zone 11 rotate with the drum 2, continuously lifting the unfilled electrodes from the water and raising them to a certain height before they fall freely. The rotation speed of the rotary drum peeler 100 is frequency-controlled, typically set between 8r / min and 16r / min; the residence time of the unfilled electrodes in the drum is adjustable from 15min to 30min. During this process, the unfilled electrodes rub and collide with each other. Simultaneously, under the immersion of hot water, the adhesion between the black powder and the collector is broken, and the black powder gradually peels off from the surface of the collector. Multiple second buffer rings (second buffer ring 17, second buffer ring 18, and second buffer ring 19) are installed within the stripping zone 11. Their height decreases progressively along the material's direction of travel, buffering the material's movement and extending its residence time in the stripping zone 11. This ensures more thorough stripping, and the gradually decreasing height also results in different residence times for the material in different sections. For example, the longest residence time is before second buffer ring 17, and the shortest residence time is before second buffer ring 19. The discharge scoop 22 near the inlet of each second buffer ring smoothly guides the material from the lower section to the top of the higher section, achieving step-by-step material transport. When the material reaches the end of the stripping zone 11, the discharge scraper 15 scrapes the collected material towards the discharge port 21 on the end plate, allowing it to enter the screening section 12. The current collector entering the screening section 12 moves towards the discharge end of the cylinder 2 under the action of the arc-shaped guide plate 14, while the slurry mixed with black powder seeps out through the screen holes on the inner wall of the screening section 12 and is collected by the discharge cylinder 5 fitted around the outer periphery of the screening section 12. At the same time, the water spray pipe 16 located above the cylinder 2 inside the discharge cylinder 5 continuously washes the outer surface of the cylinder 2 to prevent the black powder slurry from adhering and clogging the screen holes. After the current collector is discharged from the end of the screening section 12, it enters the deep cleaning machine 200 for deep cleaning; while the collected black powder slurry enters the concentration and filtration combined centrifuge 300 for solid-liquid separation. The separated black powder has a water content between 22% and 25%, and is subsequently dried to achieve the separation and recovery of the current collector and black powder. Throughout the process, the circulating water system provides and maintains hot water at the required temperature through the circulating water tank 500, and uses the graphene heat exchanger 400 to recover the heat from the high-temperature exhaust gas of the subsequent roasting process, achieving efficient energy utilization. The angle adjustment mechanism 8 can adjust the tilt angle of the cylinder 2 according to the actual working conditions to optimize the residence time and processing effect of the material in the cylinder 2.

[0048] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A process for the water washing, stripping, and recycling of unfilled electrodes, characterized in that, Includes the following steps: S1. Cut the unfilled electrode into sheets for easy insertion into subsequent equipment; S2. A water washing process is used to soak the unfilled electrode while stirring it, so that the black powder attached to the current collector is detached in one piece. S3. The black powder and the current collector are separated through the sieve holes. The black powder is dispersed by the water flow and passes through the sieve holes to form a black powder slurry. The current collector is intercepted by the sieve holes and continues to be transported forward. S4. The separated current collector enters the deep cleaning machine for deep cleaning. The cleaned slurry is then incorporated into the black powder slurry. The cleaned current collector is then compressed into briquettes for recycling. S5. The black powder slurry is dried to remove moisture, thus completing the separation and recycling of black powder and the current collector.

2. The process for washing, stripping, and recovering unfilled electrodes according to claim 1, characterized in that, After step S4 and before step S5, a fine filtration stage is provided to finely filter the black powder slurry and remove any debris that may be present in the current collector.

3. The process for washing, stripping, and recovering unfilled electrodes according to claim 2, characterized in that, The fine filtration stage uses a microporous filter with a pore size of 0.15mm to 0.2mm.

4. The process for washing, stripping, and recovering unfilled electrodes according to claim 1, characterized in that, In step S2, the water washing process involves immersing the unfilled electrodes in water at 50°C to 80°C, and using equipment to lift and release the unfilled electrodes so that they fall. Through the mutual friction and impact of the falling electrodes, the black powder and the current collector are separated.

5. A production line for the water washing, stripping, and recycling of un-liquid-filled electrodes, characterized in that, A rotary drum stripper for implementing the recycling process as described in any one of claims 1 to 4, including a water washing process.

6. The un-liquid-filled electrode water washing stripping and recycling production line according to claim 5, characterized in that, The rotary drum peeling machine includes a frame, a cylinder, a feeding device, a roller device, a discharge cylinder, and a drive mechanism. The cylinder is rotatably mounted on the frame. The feeding device is fixedly mounted on the frame, and the feeding device is provided with an electrode feeding port and a water pipe inlet; The cylinder and the feeding device are rotatably connected together via a sealing element; the cylinder is divided into a stripping zone and a screening zone; Several lifting plates are provided along the axial direction on the inner wall of the stripping zone, which are used to lift the unfilled electrode located in the stripping zone to a certain height to obtain a better stirring effect. The inner wall of the screening zone is provided with several sieve holes for separating the slurry mixed with black powder from the collecting fluid; the end of the stripping zone is provided with a discharge scraper. The end plate at the junction of the stripping zone and the screening zone is provided with a discharge port, and one end of the discharge scraper is connected to the discharge port; The discharge cylinder is fixedly mounted on the frame and sleeved around the outer periphery of the screening section of the cylinder body, for guiding the screened slurry. The drive mechanism is used to drive the cylinder to rotate around the axis.

7. The un-liquid-injected electrode water washing stripping and recycling production line according to claim 6, characterized in that, The rotary drum peeling machine also includes an angle adjustment mechanism, on which the machine frame is mounted. The angle adjustment mechanism is used to adjust the tilt angle of the drum.

8. The un-liquid-filled electrode water washing stripping and recycling production line according to claim 6, characterized in that, The discharge cylinder of the rotary drum peeler is equipped with a water spray pipe located above the cylinder body for rinsing the outer surface of the cylinder body.

9. The un-liquid-filled electrode water washing stripping and recycling production line according to claim 6, characterized in that, A first buffer ring is provided between the stripping zone and the screening zone. The first buffer ring has a notch for buffering and guiding the material entering the screening zone from the stripping zone. At least one second buffer ring is provided in the stripping zone. Among the adjacent second buffer rings, the height of the second buffer ring closer to the feed inlet is greater than the height of the second buffer ring closer to the discharge outlet.

10. The un-liquid-filled electrode water washing stripping and recycling production line according to claim 9, characterized in that, Each of the second buffer rings is provided with a discharge spoon near the inlet side. The discharge spoon extends smoothly from the inner wall of the cylinder to the top of the second buffer ring and is inclined toward the discharge port side.

Images