A device and method for recycling graphite negative electrode material in waste lithium batteries

Abstract

The application discloses a device and method for recycling graphite negative electrode material in waste lithium batteries, and relates to the technical field of lithium battery graphite negative electrode recycling and regeneration. The device is characterized by a two-stage shearing structure of a single set of multi-stage cutters in the crushing process. In a single roller pressing stroke, the top blade of the crushing cutter in the extended state first cuts into the negative electrode sheet, completes the first-stage cutting and cracking, and synchronously cracks and peels the surface graphite layer and the copper foil substrate. During the retraction process of the crushing cutter, the two side blades form a second-stage shearing pair with the shearing pressure block, and the edge of the negative electrode sheet is subjected to shearing action again. The single set of cutters can complete twice shearing in one roller pressing, and the graphite layer and the copper foil are completely peeled off. Subsequently, the copper foil wrinkles are brushed by the depth brush of the rubbing roller, the negative pressure is used to separate the free graphite, the residual powder is removed by the air curtain of the roller, the mutual entrainment amount of the two materials is significantly reduced, and the recovery purity and the comprehensive recovery rate of the graphite powder and the copper foil are simultaneously improved.

Description

Technical Field

[0001] This invention relates to the field of lithium battery graphite anode recycling technology, specifically to an apparatus and method for recycling graphite anode materials from waste lithium batteries. Background Technology

[0002] With the rapid development of the new energy vehicle and consumer electronics industries, the production, sales, and installed base of lithium-ion batteries have continued to climb, leading to a year-on-year increase in the volume of waste lithium batteries. Their resource recycling has become a crucial link in the green development of the lithium battery industry chain. Graphite, as the core material of lithium battery anodes, possesses high recycling value. However, compared to the recycling of cathode metal materials, the recycling of graphite anodes has long been limited by insufficient technological maturity and low economic efficiency. Developing efficient and low-cost physical recycling equipment has become a key research and development direction for the current lithium battery recycling industry.

[0003] Currently, the recycling of graphite anodes from spent lithium batteries mainly relies on physical methods. These methods use mechanical force to separate the graphite coating from the copper foil current collector, followed by sieving to separate the two materials. However, in practical industrial applications, existing recycling equipment and processes still have several common shortcomings.

[0004] Referring to the patent application with publication number CN116259876B, a method for recycling graphite material from lithium-ion battery negative electrodes is disclosed. This method uses a blade with a specific structure and combines optimal crushing speed, frequency, and time to recycle graphite material from negative electrodes using physical and mechanical methods. Compared with traditional sharp blade crushing, the resulting negative electrode material has a lower Cu content, which is far below the industry standard requirements, thus improving the recycling quality and showing good application prospects.

[0005] The existing graphite material recycling methods described above have the following drawbacks in practical use:

[0006] 1) In the crushing and dissociation stage, the existing mainstream roller pressing and shearing crushing devices have a single mechanical action on the negative electrode sheet. Under a single action, the degree of interface peeling between the graphite coating and the copper foil current collector is limited. It is often necessary to configure multiple crushing units in series to achieve the preset dissociation effect, resulting in a lengthy processing flow and high equipment investment costs. At the same time, the shearing action of multiple crushing units is prone to over-pulverizing the copper foil. The resulting fine copper powder will be mixed into the graphite powder, which will greatly increase the difficulty of subsequent graphite purification process and directly restrict the purity level of the recycled graphite products.

[0007] 2) In the material separation stage, most existing recycling processes adopt a processing mode of full crushing followed by centralized sorting. During the material transportation and subsequent process flow, the crushed graphite powder is easy to re-adhere to the copper foil surface, or be trapped in the gaps and agglomerates of copper foil fragments. This not only increases the processing load of the downstream sorting unit, but also causes secondary mixing of graphite and copper foil, reducing the final material separation accuracy.

[0008] Therefore, this invention proposes an apparatus and method for recycling graphite anode materials from waste lithium batteries to solve the above-mentioned problems. Summary of the Invention

[0009] To address the shortcomings of existing technologies, this invention provides an equipment and method for recycling graphite anode materials from waste lithium batteries. It solves the problems of traditional crushing and dissociation processes where roller pressing and shearing devices operate in a single manner, requiring multiple stages in series to achieve the desired dissociation effect. This results in a long process, high cost, and a tendency for copper foil to be over-pulverized, leading to fine copper powder mixing into the graphite, significantly increasing purification difficulty and limiting the purity of the recycled graphite. Furthermore, in the material separation stage, existing processes often employ a full-volume crushing followed by centralized sorting mode, where dissociated graphite powder is easily re-adheded or trapped, increasing the load on downstream sorting and causing secondary mixing, thus reducing separation accuracy.

[0010] To achieve the above objectives, the present invention provides the following technical solution: a device for recycling graphite anode material from waste lithium batteries, comprising a support frame and a protective cover fixedly disposed on one side of the top of the support frame, wherein a feeding hopper for feeding waste lithium battery graphite anode material into the protective cover is fixedly disposed on the top of the protective cover, and further comprising:

[0011] The first and second crushing mechanisms are arranged facing each other inside the upper part of the protective cover. They are used to crush the graphite negative electrode material by opposing roller pressing, and to achieve the initial separation of graphite powder and copper foil matrix while crushing the negative electrode sheet.

[0012] The first and second rubbing rollers are arranged inside the protective cover and directly below the first and second crushing mechanisms, rotating in opposite directions. They are used to rub the crushed negative electrode mixture against the rollers to deeply peel off the graphite powder adhering to the copper foil surface, thus completing the further separation of graphite from the copper foil.

[0013] The first negative pressure suction component and the second negative pressure suction component are respectively located on both sides of the first crushing mechanism and the second crushing mechanism. They are used to generate suction negative pressure synchronously by relying on the transmission power of the crushing mechanism, and extract the dissociated graphite powder in real time during the crushing and kneading operation, so as to complete the first-level separation simultaneously and greatly reduce the burden of subsequent material separation.

[0014] The secondary separation component, located on one side of the top of the support frame, is used for final fine screening of the copper foil fragments after the previous process, completely removing the residual graphite powder entrained in the copper foil fragments, and realizing the graded collection of the two recyclable materials, copper foil and graphite powder.

[0015] Furthermore, one end of the first crushing mechanism and the second crushing mechanism rotatably passes through the protective cover and is fixedly provided with crushing transmission gears. The two crushing transmission gears are meshed with each other. One end of the first kneading roller and the second kneading roller rotatably passes through the protective cover and is fixedly provided with kneading transmission gears. The two kneading transmission gears are meshed with each other. The back of the protective cover is also fixedly provided with a first servo motor and a second servo motor for driving the second crushing mechanism and the second kneading roller to rotate. The output shaft of the first servo motor rotatably passes through the protective cover and is fixedly connected to one end of the second crushing mechanism. The output shaft of the second servo motor rotatably passes through the protective cover and is fixedly connected to one end of the second kneading roller.

[0016] Furthermore, multiple tough steel bristles are uniformly fixed on the outer walls of the first and second kneading rollers, and the multiple tough steel bristles at the closest positions on the outer walls of the two rollers are arranged in an alternating pattern.

[0017] Furthermore, the first negative pressure suction assembly and the second negative pressure suction assembly have the same structure. The first negative pressure suction assembly includes a wind duct fixedly installed on the inner wall of the protective cover. A gearbox is also fixedly installed at one end of the wind duct. The input shaft of the gearbox is fixedly connected to a driven gear meshing with an adjacent crushing transmission gear. The output end rotates through the wind duct and is fixedly connected to a transmission shaft to accelerate the rotational speed of the transmission shaft. An exhaust pipe connected to the interior of the transmission shaft is fixedly installed at the other end of the transmission shaft. Multiple fan blades are also evenly fixedly installed on the outer wall of the transmission shaft. A graphite powder separation pipe is installed below the wind duct. The bottom end of the graphite powder separation pipe is fixedly installed through the protective cover and connected to a graphite powder collection device. A first guide plate is fixedly installed at the other end of the graphite powder separation pipe. Multiple first screening holes connected to the interior of the graphite powder separation pipe are evenly opened on the outer wall of the first guide plate. An air duct is fixedly installed on the outer wall of the wind duct and on one side of the fan blades. The bottom end of the air duct is fixedly connected to the outer wall of the graphite powder separation pipe to connect the ventilation duct and the internal space of the graphite powder separation pipe.

[0018] A filter screen is fixedly installed at the bottom of the air duct to prevent graphite powder from entering the air duct. A graphite powder conduit is also fixedly installed on one side of the bottom of the graphite powder separation tube. A second guide plate is fixedly installed at the bottom of the graphite powder conduit. Multiple second screening holes that communicate with the inside of the graphite powder separation tube are evenly opened on the outer wall of the second guide plate. The inner diameter of the first screening hole and the second screening hole is larger than the graphite powder particles with the largest particle size and smaller than the copper foil particles with the smallest particle size. The two first guide plates and the two second guide plates in the first negative pressure suction assembly and the second negative pressure suction assembly are all fixedly installed on the inner wall of the protective cover and are all arranged in an inverted V-shape.

[0019] Furthermore, the first crushing mechanism and the second crushing mechanism have the same structure. The first crushing mechanism includes a crushing roller that is rotatably disposed inside a protective cover. Multiple crushing tool mounting slots are evenly provided on the outer wall of the crushing roller. Each crushing tool mounting slot includes a first mounting slot. Second mounting slots are provided on both sides of the first mounting slot. Two third mounting slots are provided on both sides of the bottom of the second mounting slot. Each crushing tool mounting slot is provided with a multi-stage crushing tool.

[0020] The multi-stage crushing tool includes a telescopic rod slidably disposed in a first mounting groove. A crushing blade is fixedly disposed on the top of the telescopic rod, and first lifting columns are fixedly disposed on both sides of the bottom. The two first lifting columns are fixedly disposed at the bottom of the first mounting groove. Guide holes adapted to the structure of the two first lifting columns are also opened on both sides of the bottom of the telescopic rod. The two first lifting columns are slidably disposed in the two guide holes respectively. A first return spring is slidably sleeved on the outer wall of the first lifting column and located between the first mounting groove and the telescopic rod.

[0021] Furthermore, a side plate is fixedly provided on the outer wall of the crushing roller and on both sides of each second mounting groove. A shearing pressure block is slidably provided between the two side plates. The bottom of the shearing pressure block is slidably provided in the second mounting groove at the corresponding position. Two second lifting columns are also fixedly provided at the bottom of the shearing pressure block. The two second lifting columns are slidably provided in the two third mounting grooves at the corresponding positions. A second return spring is slidably sleeved on the outer wall of the second lifting column and between the second mounting groove and the shearing pressure block.

[0022] Furthermore, the secondary separation assembly includes a screening roller rotatably mounted on one side of the top of the support frame. A gear ring is fixedly fitted on one side of the outer wall of the screening roller, and a screening gear meshes on one side of the gear ring. A screening power shaft is fixedly mounted on one end of the screening gear. A third servo motor is also fixedly mounted on one side of the top of the support frame. The output shaft of the third servo motor is fixedly connected to one end of the screening power shaft. A graphite powder output pipe is also fixedly mounted inside the support frame and below the screening roller. The top opening area of ​​the graphite powder output pipe is larger than the horizontal projection area of ​​the secondary separation assembly.

[0023] Furthermore, the inner wall of the screening roller is fixedly provided with hollowed-out spiral guide blades, and a fixed air separator pipe is coaxially inserted inside the screening roller. The two ends of the fixed air separator pipe are fixedly installed on the support frame by support brackets and do not rotate with the screening roller. The pipe wall of the fixed air separator pipe is evenly opened with multiple sets of obliquely arranged air separator nozzles along the axial direction, and the spray direction of the air separator nozzles is directly facing the area where the material is thrown when the screening roller rotates. The air inlet end of the fixed air separator pipe is connected to the exhaust pipes of the first negative pressure suction component and the second negative pressure suction component through pipelines, so as to introduce the positive pressure exhaust generated by the negative pressure suction into the interior of the screening roller to form a turbulent air curtain.

[0024] Furthermore, several sets of dispersing lever assemblies are rotatably installed on the opposite sidewalls of the two first guide plates along the material falling direction. Each set of dispersing lever assemblies includes a rotating shaft and multiple flexible teeth evenly fixed on the outer wall of the rotating shaft. A pneumatic impeller is fixedly fitted at one end of each rotating shaft. The pneumatic impeller is directly opposite the airflow channel connecting the air duct and the graphite powder separation pipe. The high-speed airflow formed by negative pressure suction drives the pneumatic impeller to rotate, causing the flexible teeth to continuously sweep the material receiving surface of the first guide plate.

[0025] This invention also discloses a method for recycling graphite anode materials from waste lithium batteries, using equipment for recycling graphite anode materials from waste lithium batteries, and the method includes the following steps:

[0026] Step 1, Material Feeding: The waste lithium battery graphite anode material is fed into the protective cover through the feeding hopper. The material falls by its own weight into the gap area between the rollers of the first crushing mechanism and the second crushing mechanism.

[0027] Step 2, Roller Crushing and Separation: The graphite anode material is subjected to opposing roller crushing by the first crushing mechanism and the second crushing mechanism arranged in opposite directions, which simultaneously breaks the anode sheet and achieves the initial separation of graphite powder and copper foil matrix.

[0028] Step 3, Kneading and Deep Peeling: The crushed negative electrode mixture falls to the first and second kneading rollers below by its own weight. The mixture is kneaded by the opposite rotation of the two kneading rollers, deeply peeling off the graphite powder adhering to the copper foil surface, and completing the further separation of graphite and copper foil.

[0029] Step 4, negative pressure primary separation: During the crushing and kneading process, the first negative pressure suction component and the second negative pressure suction component, which are set on both sides of the crushing mechanism, generate suction negative pressure synchronously by relying on the transmission power of the crushing mechanism, and extract the dissociated graphite powder in real time, thus completing the primary material separation simultaneously.

[0030] Step 5, Terminal Classification and Collection: The kneaded mixture is conveyed in a closed manner through the graphite copper foil fragment conveying pipe to the secondary separation component on the support frame. The secondary separation component performs terminal fine screening of the copper foil fragments to remove the residual graphite powder entrained in the copper foil fragments, and finally realizes the classification and collection of the two recyclable materials, copper foil and graphite powder.

[0031] This invention provides an apparatus and method for recycling graphite anode materials from spent lithium batteries. Compared with existing technologies, it has the following advantages:

[0032] 1. An apparatus and method for recycling graphite anode materials from waste lithium batteries. This invention constructs a four-stage gradient dissociation system along the material flow direction: "initial crushing and dissociation—deep peeling through kneading—real-time negative pressure separation—final air classification and fine separation." The crushing process innovatively employs a two-stage shearing structure with a single set of multi-stage blades: within a single roller pressing stroke, the tip of the extended crushing blade first cuts into the anode sheet, completing the first stage of cutting and splitting, causing the copper foil substrate to crack and the surface graphite layer to simultaneously break and peel off; as the roller pressing force increases, the two sides of the crushing blade retract during the retraction process, forming a second-stage shearing pair with the shearing pressure block, applying shearing action again to the edge of the anode sheet. Without relying on the blades of the opposite roller, a single set of blades can complete two shearing operations in one roller pressing, more thoroughly breaking up the copper foil substrate and promoting complete peeling of the graphite layer from the copper foil, significantly improving the graphite dissociation efficiency in the crushing stage. Subsequently, the copper foil wrinkles are brushed with a rubbing roller, free graphite is extracted in real time under negative pressure, and residual powder is removed by a drum air curtain. The separation effect is enhanced step by step, significantly reducing the amount of mutual entrainment between the two materials, and simultaneously improving the recovery purity and overall recovery rate of graphite powder and copper foil.

[0033] 2. An apparatus and method for recycling graphite anode materials from waste lithium batteries. This invention employs a power reuse design in multiple places. The negative pressure suction component directly draws power from the crushing mechanism through gear meshing, and the power of the crushing transmission synchronously drives the fan blades to rotate and generate negative pressure, eliminating the need for a separate suction motor. The dispersing lever at the guide plate uses the high-speed airflow of the negative pressure suction to drive the pneumatic impeller to rotate, which can disperse agglomerated materials without an additional power source. The final air separation process reuses the positive pressure exhaust gas discharged from the negative pressure suction as an air source, converting the exhaust gas into air separation power. This reduces the configuration of drive components in multiple stages, simultaneously reducing equipment manufacturing costs and production operation energy consumption, and improving energy utilization efficiency.

[0034] 3. An apparatus and method for recycling graphite anode materials from waste lithium batteries, which incorporates elastic buffer structures for core operating components susceptible to impact, such as crushing and kneading. The two-stage shearing structure of the crushing blades is equipped with return springs, automatically retracting radially to relieve force when encountering hard foreign objects, preventing blade breakage due to rigid impact. The kneading rollers use tough steel bristles, relying on their own elastic deformation to complete the brushing operation, buffering material impact and reducing component wear. This design effectively reduces the wear rate of vulnerable parts, extends the continuous operating life of the equipment, and reduces the frequency of downtime maintenance and spare parts replacement costs.

[0035] 4. An apparatus and method for recycling graphite anode materials from waste lithium batteries, comprising: simultaneously installing negative pressure suction components on both sides of the crushing and kneading processes, combined with a two-stage material guiding and screening structure and a pneumatic dispersing lever, to simultaneously complete the first-stage separation during the material falling process; real-time extraction of dissociated graphite powder during operation to prevent dissociated graphite from entering subsequent processes with the material; the dispersing lever can break up agglomerated material clumps, releasing the encapsulated graphite powder, enhancing the first-stage separation effect, removing the vast majority of free graphite powder at the front end, significantly reducing the processing load of the terminal secondary separation, and effectively improving the overall processing capacity and operating efficiency of the equipment.

[0036] 5. An apparatus and method for recycling graphite anode materials from waste lithium batteries, wherein the secondary separation employs a composite structure coupling drum screening and built-in air classifier: an inclined screening roller combined with hollowed-out spiral guide blades can precisely control the residence time of materials in the drum, achieving continuous and fine screening; the built-in fixed air classifier pipe sprays oblique airflow to form a diffused air curtain, which on the one hand blows away the falling materials and removes residual graphite trapped in the copper foil folds, improving screening accuracy; on the other hand, the airflow passes through the screen holes from the inside to the outside, blowing away the powder embedded in the screen holes in the reverse direction, achieving screen hole self-cleaning. This structure ensures the separation accuracy of the final screening while avoiding the decrease in processing efficiency caused by screen hole blockage, eliminating the need for frequent shutdowns for cleaning, and is suitable for large-scale continuous industrial production scenarios.

[0037] 6. An apparatus and method for recycling graphite anode material from waste lithium batteries, wherein the kneading process uses tough steel bristles to peel off graphite powder through a flexible action of brushing and patting, rather than rigid shearing and crushing. This avoids excessive shredding of copper foil, ensures the overall size integrity of copper foil fragments, and reduces the generation of fine copper powder. This reduces the copper impurity content in the graphite powder, improves the quality of recycled graphite, and ensures the integrity of the recycled copper foil, thereby increasing the subsequent reuse value of the copper foil. Attached Figure Description

[0038] Figure 1 This is a schematic diagram of the first overall three-dimensional structure of the present invention;

[0039] Figure 2 This is a schematic diagram of the second overall three-dimensional structure of the present invention;

[0040] Figure 3 This is a schematic cross-sectional view of the present invention;

[0041] Figure 4 For the present invention Figure 3 A magnified structural diagram of part A in the diagram;

[0042] Figure 5 This is a schematic diagram of the assembly structure of the first crushing mechanism, the second crushing mechanism, the first negative pressure suction mechanism, the second negative pressure suction mechanism, the first kneading roller, and the second kneading roller of the present invention.

[0043] Figure 6 This is a schematic diagram of the overall structure of the first negative pressure suction component of the present invention;

[0044] Figure 7 This is a cross-sectional view of the first negative pressure suction component of the present invention;

[0045] Figure 8 This is a schematic diagram of the assembly structure of the secondary separation component and the graphite copper foil fragment separation and conveying pipe of the present invention;

[0046] Figure 9 This is a schematic diagram of the overall structure of the first and second crushing mechanisms of the present invention in their assembled state.

[0047] Figure 10 This is a top view of the assembly state of the first and second crushing mechanisms of the present invention.

[0048] Figure 11 This is a schematic diagram of the first cross-sectional structure of the first crushing mechanism of the present invention;

[0049] Figure 12 For the present invention Figure 11 A magnified structural diagram of part B in the diagram;

[0050] Figure 13This is a schematic diagram of the second cross-sectional structure of the first crushing mechanism of the present invention;

[0051] Figure 14 For the present invention Figure 13 A magnified structural diagram of part C in the diagram;

[0052] Figure 15 This is a schematic diagram of the first crushing mechanism of the present invention performing a shearing action.

[0053] In the diagram: 1. Support frame; 2. Protective cover; 3. Feed hopper; 4. First crushing mechanism; 41. Crushing roller; 42. First mounting slot; 43. Second mounting slot; 44. Third mounting slot; 45. Telescopic rod; 46. Crushing blade; 47. First lifting column; 48. First return spring; 49. Side plate; 410. Shearing pressure block; 411. Second lifting column; 412. Second return spring; 5. Second crushing mechanism; 6. First kneading roller; 7. Second kneading roller; 8. Kneading transmission gear; 9. First negative pressure suction assembly; 91. Air duct; 92. Drive shaft; 93. Driven gear; 94. Fan blade; 95. Exhaust pipe; 96. Graphite powder separation pipe; 97. First guide plate; 98. First screening hole; 99. Air duct; 910. Graphite powder duct; 911. Second guide plate; 912. Second screening hole; 10. Second negative pressure suction assembly; 11. Secondary separation assembly; 111. Screening roller; 112. Gear ring; 113. Screening gear; 114. Screening power shaft; 115. Third servo motor; 12. Graphite powder output pipe; 13. Graphite copper foil fragment conveying pipe; 14. Crushing transmission gear; 15. First servo motor; 16. Second servo motor. Detailed Implementation

[0054] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0055] This invention provides three technical solutions: a device for recycling graphite anode materials from waste lithium batteries, specifically including the following embodiments:

[0056] like Figures 1-5 , Figure 8 The first embodiment is shown: a device for recycling graphite anode material from waste lithium batteries, including a support frame 1 and a protective cover 2 fixedly disposed on one side of the top of the support frame 1. A feeding hopper 3 for feeding waste lithium battery graphite anode material into the protective cover 2 is fixedly disposed on the top of the protective cover 2. The device also includes:

[0057] The first crushing mechanism 4 and the second crushing mechanism 5 are arranged facing each other inside the upper part of the protective cover 2. They are used to crush the graphite negative electrode material by opposing roller pressing, and to achieve the initial separation of graphite powder and copper foil matrix while crushing the negative electrode sheet.

[0058] The first kneading roller 6 and the second kneading roller 7 are arranged inside the protective cover 2 and directly below the first crushing mechanism 4 and the second crushing mechanism 5, rotating in opposite directions. They are used to knead the crushed negative electrode mixture with the rollers to deeply peel off the graphite powder adhering to the surface of the copper foil, thus completing the further separation of graphite from the copper foil.

[0059] The first negative pressure suction component 9 and the second negative pressure suction component 10 are respectively located on both sides of the first crushing mechanism 4 and the second crushing mechanism 5. They are used to generate suction negative pressure synchronously by relying on the transmission power of the crushing mechanism, and to extract the dissociated graphite powder in real time during the crushing and kneading operation, so as to complete the first-level separation simultaneously and greatly reduce the burden of subsequent material separation.

[0060] The secondary separation component 11 is located on the top side of the support frame 1 and is used to perform final fine screening of the copper foil fragments after the previous process, completely removing the residual graphite powder encased in the copper foil fragments, and realizing the graded collection of the two recyclable materials, copper foil and graphite powder.

[0061] In this embodiment of the invention, the equipment follows a material flow direction of "top-down step-by-step processing": the discharge port of the feeding hopper 3 is directly above the gap between the rollers of the first crushing mechanism 4 and the second crushing mechanism 5, ensuring that the material directly enters the crushing zone after feeding; the gap between the rollers of the two crushing mechanisms is directly above the gap between the rollers of the first kneading roller 6 and the second kneading roller 7 below, and the crushed material falls directly into the kneading zone by its own weight, without the need for an additional conveying structure; the suction surfaces of the first negative pressure suction component 9 and the second negative pressure suction component 10 respectively cover the two sides of the crushing zone and the upper side of the kneading zone, and can simultaneously suck up the free graphite powder generated by the crushing and kneading processes; the bottom of the protective cover 2 is provided with a discharge port corresponding to the lower part of the kneading roller, and is sealed and connected to the feed end of the secondary separation component 11 through the graphite copper foil fragment conveying pipe 13, so that the kneaded mixture is conveyed to the final screening stage in a closed manner, with no dust overflow throughout the process.

[0062] In this embodiment of the invention, one end of the first crushing mechanism 4 and the second crushing mechanism 5 rotatably passes through the protective cover 2 and is fixedly provided with crushing transmission gears 14. The two crushing transmission gears 14 are meshed with each other. One end of the first kneading roller 6 and the second kneading roller 7 rotatably passes through the protective cover 2 and is fixedly provided with kneading transmission gears 8. The two kneading transmission gears 8 are meshed with each other. The back of the protective cover 2 is also fixedly provided with a first servo motor 15 and a second servo motor 16 for driving the second crushing mechanism 5 and the second kneading roller 7 to rotate. The output shaft of the first servo motor 15 rotatably passes through the protective cover 2 and is fixedly connected to one end of the second crushing mechanism 5. The output shaft of the second servo motor 16 rotatably passes through the protective cover 2 and is fixedly connected to one end of the second kneading roller 7.

[0063] In this embodiment of the invention, multiple tough steel bristles are uniformly fixed on the outer walls of the first kneading roller 6 and the second kneading roller 7, with the bristles at the closest positions on their outer walls interlaced. The tough steel bristles are arranged in multiple rows at equal intervals along the axial direction of the kneading rollers, forming multiple rings circumferentially, and are arranged in an array. Each bristle has a diameter of 0.3mm-0.8mm and a free length of 15mm-25mm, possessing elastic deformation capability. When the distance between the two kneading rollers is at its minimum, the interlacing embedding depth of the bristles on both sides is 1 / 3-1 / 2 of the total bristle length. During the kneading operation, the interlaced bristles can penetrate into the folds and gaps of the copper foil fragments, thoroughly peeling off the graphite powder adhering to the copper foil surface through brushing and beating. Simultaneously, the tough deformation of the bristles prevents rigid shearing and fragmentation of the copper foil, ensuring the overall dimensional integrity of the copper foil fragments and reducing the amount of copper powder entrained during subsequent screening.

[0064] like Figures 6-7The second embodiment is shown, which differs from the first embodiment in that: the first negative pressure suction assembly 9 and the second negative pressure suction assembly 10 have the same structure. The first negative pressure suction assembly 9 includes a duct 91 fixedly mounted on the inner wall of the protective cover 2. A gearbox is also fixedly mounted at one end of the duct 91. The input shaft of the gearbox is fixedly connected to a driven gear 93 that meshes with an adjacent crushing transmission gear 14. The output end rotates through the duct 91 and is fixedly connected to a drive shaft 92 to increase the rotational speed of the drive shaft 92. An exhaust pipe 95 communicating with the interior of the drive shaft 92 is fixedly mounted at the other end of the drive shaft 92. The outer wall of the drive shaft 92... Multiple fan blades 94 are evenly fixedly arranged on the top. A graphite powder separation tube 96 is arranged below the air duct 91. The bottom end of the graphite powder separation tube 96 is fixedly connected to the protective cover 2 and the graphite powder collection device. The other end of the graphite powder separation tube 96 is fixedly arranged with a first guide plate 97. Multiple first screening holes 98 that communicate with the inside of the graphite powder separation tube 96 are evenly opened on the outer wall of the first guide plate 97. An air duct 99 is fixedly arranged on the outer wall of the air duct 91 and on one side of the fan blades 94. The bottom end of the air duct 99 is fixedly connected to the outer wall of the graphite powder separation tube 96 and is used to connect the internal space of the air duct 91 and the graphite powder separation tube 96.

[0065] In this embodiment of the invention, a filter screen is fixedly installed at the bottom end of the air duct 99 to prevent graphite powder from entering the air duct 99. A graphite powder duct 910 is fixedly installed on one side of the bottom of the graphite powder separation tube 96. A second guide plate 911 is fixedly installed at the bottom end of the graphite powder duct 910. A plurality of second screening holes 912 that communicate with the inside of the graphite powder separation tube 96 are evenly opened on the outer wall of the second guide plate 911. The inner diameter of the first screening hole 98 and the second screening hole 912 is larger than the graphite powder particles with the largest particle size and smaller than the copper foil particles with the smallest particle size. The two first guide plates 97 and the two second guide plates 911 in the first negative pressure suction assembly 9 and the second negative pressure suction assembly 10 are all fixedly installed on the inner wall of the protective cover 2 and are all arranged in an inverted V-shape.

[0066] Driven gear 93 meshes externally with crushing transmission gear 14 on the same side. When the crushing mechanism rotates, it synchronously drives the transmission shaft 92 and fan blade 94 to rotate, without the need for an additional suction motor. When the fan blade 94 rotates, the air in the air duct 91 is discharged from the exhaust pipe 95 to form a negative pressure, which then draws the air in the graphite powder separation pipe 96 through the air duct 99, so that a stable suction negative pressure is formed inside the graphite powder separation pipe 96.

[0067] The first screening hole 98 and the second screening hole 912 have a diameter of 100-150 mesh, which can completely pass through the dissociated graphite powder particles, while intercepting all copper foil fragments; the first guide plate 97, which is arranged in an inverted V-shape, has an inclination angle of 30°-45°, ensuring that the material slides down the plate surface by its own weight; the second guide plate 911 has the same inclination direction as the first guide plate 97, and receives the material sliding down the first guide plate, which is then suctioned through the second screening hole 912 to improve the efficiency of primary graphite powder separation.

[0068] Under negative pressure, free graphite powder passes through the sieve holes with the airflow and enters the graphite powder separation tube 96. The airflow goes upward through the filter screen and air duct 99 and finally enters the air duct 91 and is discharged. The graphite powder is intercepted by the filter screen and slides down along the graphite powder separation tube 96 under the action of gravity. It enters the external graphite powder collection device from the bottom outlet, realizing gas-solid separation.

[0069] like Figures 9-15 The third embodiment is shown. The first crushing mechanism 4 and the second crushing mechanism 5 have the same structure. The first crushing mechanism 4 includes a crushing roller 41 rotatably disposed inside the protective cover 2. Multiple crushing tool mounting slots are evenly provided on the outer wall of the crushing roller 41. The crushing tool mounting slots include a first mounting slot 42. A second mounting slot 43 is provided on both sides of the first mounting slot 42. Two third mounting slots 44 are provided on both sides of the bottom of the second mounting slot 43. A multi-stage crushing tool is provided in each crushing tool mounting slot. The multi-stage crushing tool includes a telescopic rod 45 slidably disposed in the first mounting slot 42. A crushing blade 46 is fixedly disposed on the top of the telescopic rod 45. A first lifting column 47 is fixedly disposed on both sides of the bottom of the telescopic rod 45. The two first lifting columns 47 are fixedly disposed at the bottom of the first mounting slot 42. Guide holes adapted to the structure of the two first lifting columns 47 are also provided on both sides of the bottom of the telescopic rod 45. The two first lifting columns 47 are slidably disposed in the two guide holes respectively. A first return spring 48 is slidably sleeved on the outer wall of the first lifting column 47 and located between the first mounting slot 42 and the telescopic rod 45.

[0070] The crushing tool mounting slots are arranged in multiple rows at equal intervals along the axial direction of the crushing roller 41, and are evenly distributed in multiple rings around the circumference. The crushing tools of the two crushing rollers are staggered and opposite to each other. The top of the crushing tool 46 is an arc-shaped cutting edge, and the width of the cutting edge is the same as the width of the first mounting slot 42. The maximum radial extension stroke of the telescopic rod 45 is 5-8 mm. The first return spring 48 is normally in a slightly compressed state, pushing the telescopic rod 45 outward to keep the crushing tool 46 at its maximum extension. When encountering hard foreign objects or extremely thick material sections during the crushing process, the crushing tool 46 is driven by radial pressure to compress the telescopic rod 45 and retract inward to achieve elastic avoidance and prevent the tool from being broken or damaged by rigid impact. The first lifting column 47 slides with the guide hole to form a circumferential limit on the extension and retraction movement of the telescopic rod 45, ensuring that it only moves radially along the crushing roller and does not deflect or jam.

[0071] In this embodiment of the invention, side plates 49 are fixedly provided on the outer wall of the crushing roller 41 and on both sides of each second mounting groove 43. A shearing pressure block 410 is slidably provided between the two side plates 49. The bottom of the shearing pressure block 410 is slidably provided in the second mounting groove 43 at the corresponding position. Two second lifting columns 411 are also fixedly provided at the bottom of the shearing pressure block 410. The two second lifting columns 411 are slidably provided in the two third mounting grooves 44 at the corresponding positions. A second return spring 412 is slidably sleeved on the outer wall of the second lifting column 411 and between the second mounting groove 43 and the shearing pressure block 410.

[0072] When the two crushing rollers rotate in opposite directions to press the material, the single-sided single-group multi-stage crushing blades can independently achieve two-stage shearing effects in one rolling action. The specific process is as follows: the first stage of shearing is completed by the extended crushing blade 46. After the material enters the roller gap, the tip of the crushing blade 46 first contacts the negative electrode sheet and cuts in, forming an initial cut on the copper foil substrate, and at the same time causing the surface graphite layer to crack and initially separate. As the rollers continue to rotate in opposite directions and the rolling force increases, the crushing blade 46 is subjected to the reaction force of the copper foil to overcome the elastic force of the first reset spring 48 and retracts inward. During the retraction process, the two sides of the crushing blade 46 simultaneously enter the groove cavity formed by the two side plates 49 on the same side, forming a second-stage shearing pair with the top surface of the shearing bearing block 410 at the bottom of the groove, and applying shearing force again to the edge of the negative electrode sheet pressed into the groove.

[0073] Therefore, the single-unit multi-stage crushing cutter does not need to rely on the cutter cooperation of the side rollers. It can complete two shearing actions of "cutting and splitting" and "side blade shearing" in one roller pressing stroke by relying only on its own telescopic structure. The dual shearing action can more fully crush the copper foil substrate and promote the complete peeling of the graphite layer from the copper foil, which can significantly improve the graphite dissociation efficiency in the crushing stage. Under normal conditions, the second return spring 412 pushes the shearing pressure block 410 to the highest working position to ensure the stability of the shearing gap. When the shearing load suddenly increases due to foreign objects, the shearing pressure block 410 can retract slightly along the second lifting column 411 to buffer and prevent the cutter from breaking due to rigid impact. The two side plates 49 simultaneously form a lateral clamping limit on the shearing pressure block 410 to ensure that it only moves up and down radially along the crushing roller and does not deflect in the circumference or move in the axial direction.

[0074] In this embodiment of the invention, the secondary separation component 11 includes a screening roller 111 rotatably mounted on one side of the top of the support frame 1. A gear ring 112 is fixedly sleeved on one side of the outer wall of the screening roller 111. A screening gear 113 meshes on one side of the gear ring 112. A screening power shaft 114 is fixedly mounted on one end of the screening gear 113. A third servo motor 115 is also fixedly mounted on one side of the top of the support frame 1. The output shaft of the third servo motor 115 is fixedly connected to one end of the screening power shaft 114. A graphite powder output pipe 12 is also fixedly mounted inside the support frame 1 and below the screening roller 111. The top opening area of ​​the graphite powder output pipe 12 is larger than the horizontal projection area of ​​the secondary separation component 11.

[0075] The screening roller 111 is inclined at 5°-10°, with the feed end higher than the discharge end. Both ends of the roller are rotatably supported on the support frame 1 by annular support roller assemblies. Screen holes are evenly distributed through the cylinder wall of the screening roller 111, and the diameter of the screen holes is the same as that of the first screening hole 98. During operation, the third servo motor 115 drives the screening gear 113 to rotate through the screening power shaft 114, and drives the screening roller 111 to rotate at a constant speed around its own axis through the meshing transmission of the gear ring 112. The mixture enters the cylinder from the high-end feed port and moves forward with the roller. Graphite powder falls through the screen holes, and copper foil fragments are finally discharged from the low-end discharge port, realizing continuous screening. The graphite powder output pipe 12 has a funnel-shaped structure that is wider at the top and narrower at the bottom. The top opening completely covers the projected area directly below the screening roller 111, ensuring that all the screened graphite powder is collected and there is no spillage or leakage.

[0076] In this embodiment of the invention, the inner wall of the screening roller 111 is fixedly provided with hollowed-out spiral guide blades, and a fixed air separator pipe is coaxially inserted inside the screening roller 111. The two ends of the fixed air separator pipe are fixedly installed on the support frame 1 by support brackets and do not rotate with the screening roller 111. The pipe wall of the fixed air separator pipe is evenly provided with multiple sets of obliquely arranged air separator nozzles along the axial direction. The spray direction of the air separator nozzles is directly opposite to the area where the material is thrown when the screening roller 111 rotates. The air inlet end of the fixed air separator pipe is connected to the exhaust pipes 95 of the first negative pressure suction component 9 and the second negative pressure suction component 10 through pipelines, so as to introduce the positive pressure exhaust generated by the negative pressure suction into the interior of the screening roller 111 to form a disturbed air curtain.

[0077] The fixed air separator is a sealed hollow tube, fixed at both ends to the outer wall of the support frame 1 by L-shaped support arm bolts, and coaxial with the screening roller 111. Sufficient space is left between the tube wall and the inner wall of the roller for material tumbling. The air separator nozzles are arranged in multiple staggered rows along the axial direction of the tube, with the nozzle axis forming a 30° downward angle with the vertical direction, precisely corresponding to the trajectory area of ​​the material thrown down by the roller rotation. The perforated spiral guide blades have a larger perforation diameter than the sieve aperture of the screening roller 111. This allows the material to move uniformly towards the discharge end along the axial direction with the roller rotation, controlling the material's screening residence time, while also allowing airflow and graphite powder to pass freely without hindering gas-solid separation. The exhaust pipes 95 of the first negative pressure suction component 9 and the second negative pressure suction component 10 are connected to the air inlet of the fixed air classifier pipe through a three-way pipe. The positive pressure exhaust gas that was originally directly discharged is used as the power source for air classifier and reused. After the airflow is sprayed out from the air classifier nozzle, it forms a diffused air curtain, which blows away the mixed material and makes the graphite powder wrapped in the copper foil folds fully disintegrate and be lifted up. At the same time, the airflow passes out from the inside to the outside of the screen hole, which can blow away the powder embedded in the screen hole in the reverse direction, realizing the self-cleaning of the screen hole.

[0078] In this embodiment of the invention, several sets of dispersing lever assemblies are rotatably installed on the opposite side walls of the two first guide plates 97 along the material falling direction. Each set of dispersing lever assemblies includes a rotating shaft and multiple flexible teeth evenly fixed on the outer wall of the rotating shaft. A pneumatic impeller is fixedly fitted at one end of each rotating shaft. The pneumatic impeller is directly opposite the airflow channel connecting the air duct and the graphite powder separation tube. The high-speed airflow formed by negative pressure suction drives the pneumatic impeller to rotate, causing the flexible teeth to continuously sweep the material receiving surface of the first guide plate.

[0079] The two ends of the rotating shaft are rotatably fixed on the two side groove walls of the first guide plate through bearing seats with dustproof seals. The rotating shaft itself is equipped with limiting shoulders, which, together with the bearing seat end caps, achieve axial positioning, allowing it to rotate smoothly without axial movement, while preventing graphite dust from entering the bearing.

[0080] The shaft is located near one end of the graphite powder separation tube 96 and extends through the side wall of the separation tube into the tube cavity. A dynamic sealing structure is provided at the penetration point of the side wall, which neither interferes with the rotation of the shaft nor blocks the gaps, thus preventing negative pressure leakage and dust overflow inside the tube.

[0081] The end of the shaft that extends into the graphite powder separation tube is coaxially fixed to the wind turbine impeller by a key and a locking nut. The impeller is located directly below the air inlet at the bottom of the air duct 99. When the airflow is drawn upward, it directly impacts the impeller blades, causing the shaft to rotate synchronously.

[0082] The shaft section located in the material drop area of ​​the first guide plate has multiple flexible teeth evenly fixed along the axial and circumferential directions; the root of the teeth is firmly inserted into the shaft, and the free end is close to the inner wall of the guide plate. As the shaft rotates, it can disperse the falling material and sweep the material on the plate area.

[0083] This invention also provides a method for recycling graphite anode materials from spent lithium batteries, using equipment for recycling graphite anode materials from spent lithium batteries, and the method includes the following steps:

[0084] Step 1, Material Feeding: The waste lithium battery graphite anode material is fed into the protective cover through the feeding hopper. The material falls by its own weight into the gap area between the rollers of the first crushing mechanism and the second crushing mechanism.

[0085] Step 2, Roller Crushing and Separation: The graphite anode material is subjected to opposing roller crushing by the first crushing mechanism and the second crushing mechanism arranged in opposite directions, which simultaneously breaks the anode sheet and achieves the initial separation of graphite powder and copper foil matrix.

[0086] Step 3, Kneading and Deep Peeling: The crushed negative electrode mixture falls to the first and second kneading rollers below by its own weight. The mixture is kneaded by the opposite rotation of the two kneading rollers, deeply peeling off the graphite powder adhering to the copper foil surface, and completing the further separation of graphite and copper foil.

[0087] Step 4, negative pressure primary separation: During the crushing and kneading process, the first negative pressure suction component and the second negative pressure suction component, which are set on both sides of the crushing mechanism, generate suction negative pressure synchronously by relying on the transmission power of the crushing mechanism, and extract the dissociated graphite powder in real time, thus completing the primary material separation simultaneously.

[0088] Step 5, Terminal Classification and Collection: The kneaded mixture is conveyed in a closed manner through the graphite copper foil fragment conveying pipe to the secondary separation component on the support frame. The secondary separation component performs terminal fine screening of the copper foil fragments to remove the residual graphite powder entrained in the copper foil fragments, and finally realizes the classification and collection of the two recyclable materials, copper foil and graphite powder.

[0089] In use, the first servo motor 15, the second servo motor 16, and the third servo motor 115 on the support frame 1 are started; the first servo motor 15 drives the second crushing mechanism 5 inside the protective cover 2 to rotate, and through the two meshing crushing transmission gears 14, drives the first crushing mechanism 4 and the second crushing mechanism 5 to rotate synchronously in opposite directions; the second servo motor 16 drives the second kneading roller 7 to rotate, and through the two meshing kneading transmission gears 8, drives the first kneading roller 6 and the second kneading roller 7 to rotate synchronously in opposite directions; the third servo motor 115 drives the screening power shaft 114 to... The rotating screening gear 113 drives the screening roller 111 of the secondary separation component 11 to rotate around its own axis via the meshing transmission of the gear ring 112. At the same time, the two crushing transmission gears 14 respectively mesh to drive the driven gears 93 of the first negative pressure suction component 9 and the second negative pressure suction component 10 to rotate. After being accelerated by the gearbox, the transmission shaft 92 and the fan blade 94 rotate at high speed in the air duct 91, so that a stable suction negative pressure is formed inside the graphite powder separation tube 96. When the negative pressure airflow flows through the air duct 99, it impacts the wind turbine to rotate, driving the flexible teeth on the first guide plate 97 to rotate synchronously.

[0090] Waste lithium battery graphite anode material is fed into the protective cover 2 through the feeding hopper 3. The material falls under its own weight to the gap between the rollers of the first crushing mechanism 4 and the second crushing mechanism 5. The two crushing rollers 41 rotate in opposite directions, and the arc-shaped cutting edge of the crushing blade 46 cuts into the anode sheet first, completing the first stage of cutting and splitting, causing the surface graphite layer to crack and initially separate from the copper foil. As the roller pressure increases, the crushing blade 46 drives the telescopic rod 45 to compress the first return spring 48 along the first lifting column 47 and move towards the first mounting groove. The shearing block 410 between the two sides of the cutting blade 46 and the side plate 49 forms a second-stage shearing pair, which applies shearing action to the negative electrode sheet pressed into the groove again. When encountering hard foreign objects, the shearing block 410 compresses the second return spring 412 along the second lifting column 411 and retracts into the third mounting groove 44 at the bottom of the second mounting groove 43 to buffer and avoid blade breakage. The copper foil substrate is fully broken by the two-stage shearing action, and the graphite powder and copper foil are initially separated.

[0091] The crushed negative electrode mixture falls under its own weight to the gap between the first kneading roller 6 and the second kneading roller 7. The two kneading rollers rotate in opposite directions, and the tough steel bristles arranged in an array on the outer wall interweave and insert into the folds and gaps of the copper foil fragments. Through brushing and patting, the graphite powder adhering to the surface of the copper foil is deeply peeled off, and the graphite and copper foil are further separated. During the kneading process, the bristles rely on their own tough deformation to avoid rigid shearing and cutting the copper foil, so as to ensure the overall size integrity of the copper foil fragments.

[0092] The free graphite powder generated during the crushing and kneading process is drawn into the graphite powder separation tube 96 by the airflow through the first screening hole 98 on the first guide plate 97 under the suction negative pressure of the first negative pressure suction component 9 and the second negative pressure suction component 10. As the falling material slides down the first guide plate 97, which is arranged in an inverted V-shape, the continuously rotating flexible teeth break up the agglomerated material clumps, promoting the full exposure of the encapsulated graphite powder for suction and separation. The material slides down the first guide plate 97 to the second guide plate 96. At point 11, the remaining free graphite powder passes through the second screening hole 912 and flows into the graphite powder separation pipe 96 via the graphite powder conduit 910, completing the secondary suction screening; the graphite powder is intercepted by the filter screen at the end of the air conduit 99 and falls down along the graphite powder separation pipe 96 to the external graphite powder collection device under the action of gravity, while the airflow enters the air duct 91 through the air conduit 99 and is discharged from the exhaust pipe 95; the copper foil fragments are intercepted by the first screening hole 98 and the second screening hole 912 and slide down along the guide plate to the bottom discharge port of the protective cover 2.

[0093] The kneaded copper foil fragment mixture is conveyed in a closed manner through the graphite copper foil fragment conveying pipe 13 to the feed end of the screening roller 111 of the secondary separation component 11. When the inclined screening roller 111 rotates, the hollow spiral guide blades on the inner wall push the material slowly towards the discharge end. During the tumbling process of the material with the roller, the residual graphite powder falls through the screen holes in the cylinder wall and is collected in the graphite powder output pipe 12. At the same time, the exhaust of the first negative pressure suction component 9 and the second negative pressure suction component 10 is also affected. The positive pressure airflow discharged from pipe 95 merges into the fixed air separator pipe and is sprayed obliquely through the air separator nozzle to form a diffused turbulent air curtain, which blows away the mixed material in a falling state, so that the graphite powder wrapped in the copper foil folds is fully dissociated and lifted up. At the same time, the airflow passes through the screen holes from the inside to the outside, blowing away the powder embedded in the screen holes in the reverse direction to achieve screen hole self-cleaning. Finally, the copper foil fragments are discharged and collected from the discharge end of the screening roller 111, completing the full-process graded recycling of graphite powder and copper foil in waste lithium battery graphite anode materials.

[0094] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0095] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A device for recycling graphite anode material from waste lithium batteries, comprising a support frame and a protective cover fixedly disposed on one side of the top of the support frame, wherein a feeding hopper for feeding waste lithium battery graphite anode material into the protective cover is fixedly disposed on the top of the protective cover, characterized in that, Also includes: The first and second crushing mechanisms are arranged facing each other inside the upper part of the protective cover. They are used to crush the graphite negative electrode material by opposing roller pressing, and to achieve the initial separation of graphite powder and copper foil matrix while crushing the negative electrode sheet. The first and second rubbing rollers are arranged inside the protective cover and directly below the first and second crushing mechanisms, rotating in opposite directions. They are used to rub the crushed negative electrode mixture against the rollers to deeply peel off the graphite powder adhering to the copper foil surface, thus completing the further separation of graphite from the copper foil. The first negative pressure suction component and the second negative pressure suction component are respectively located on both sides of the first crushing mechanism and the second crushing mechanism. They are used to generate suction negative pressure synchronously by relying on the transmission power of the crushing mechanism, and extract the dissociated graphite powder in real time during the crushing and kneading operation, so as to complete the first-level separation simultaneously and greatly reduce the burden of subsequent material separation. The secondary separation component, located on one side of the top of the support frame, is used for final fine screening of the copper foil fragments after the previous process, completely removing the residual graphite powder entrained in the copper foil fragments, and realizing the graded collection of the two recyclable materials, copper foil and graphite powder.

2. The equipment for recycling graphite anode material from waste lithium batteries according to claim 1, characterized in that: One end of the first crushing mechanism and the second crushing mechanism rotatably passes through the protective cover and is fixedly equipped with crushing transmission gears. The two crushing transmission gears are meshed with each other. One end of the first kneading roller and the second kneading roller rotatably passes through the protective cover and is fixedly equipped with kneading transmission gears. The two kneading transmission gears are meshed with each other. The back of the protective cover is also fixedly equipped with a first servo motor and a second servo motor for driving the second crushing mechanism and the second kneading roller to rotate. The output shaft of the first servo motor rotatably passes through the protective cover and is fixedly connected to one end of the second crushing mechanism. The output shaft of the second servo motor rotatably passes through the protective cover and is fixedly connected to one end of the second kneading roller.

3. The equipment for recycling graphite anode material from waste lithium batteries according to claim 1, characterized in that: Multiple tough steel bristles are uniformly fixed on the outer walls of the first and second kneading rollers, and the multiple tough steel bristles at the closest positions on the outer walls of the two rollers are arranged in an alternating pattern.

4. The equipment for recycling graphite anode material from waste lithium batteries according to claim 2, characterized in that: The first negative pressure suction assembly and the second negative pressure suction assembly have the same structure. The first negative pressure suction assembly includes a wind duct fixedly installed on the inner wall of the protective cover. A gearbox is also fixedly installed at one end of the wind duct. The input shaft of the gearbox is fixedly connected to a driven gear that meshes with an adjacent crushing transmission gear. The output end rotates through the wind duct and is fixedly connected to a transmission shaft to increase the rotational speed of the transmission shaft. An exhaust pipe connected to the interior of the transmission shaft is fixedly installed at the other end of the transmission shaft. Multiple fan blades are also evenly fixedly installed on the outer wall of the transmission shaft. A graphite powder separation pipe is installed below the wind duct. The bottom end of the graphite powder separation pipe is fixedly installed through the protective cover and connected to a graphite powder collection device. A first guide plate is fixedly installed at the other end of the graphite powder separation pipe. Multiple first screening holes connected to the interior of the graphite powder separation pipe are evenly opened on the outer wall of the first guide plate. An air duct is fixedly installed on the outer wall of the wind duct and on one side of the fan blades. The bottom end of the air duct is fixedly connected to the outer wall of the graphite powder separation pipe to connect the ventilation duct and the internal space of the graphite powder separation pipe. A filter screen is fixedly installed at the bottom of the air duct to prevent graphite powder from entering the air duct. A graphite powder conduit is also fixedly installed on one side of the bottom of the graphite powder separation tube. A second guide plate is fixedly installed at the bottom of the graphite powder conduit. Multiple second screening holes that communicate with the inside of the graphite powder separation tube are evenly opened on the outer wall of the second guide plate. The inner diameter of the first screening hole and the second screening hole is larger than the graphite powder particles with the largest particle size and smaller than the copper foil particles with the smallest particle size. The two first guide plates and the two second guide plates in the first negative pressure suction assembly and the second negative pressure suction assembly are all fixedly installed on the inner wall of the protective cover and are all arranged in an inverted V-shape.

5. The equipment for recycling graphite anode material from waste lithium batteries according to claim 1, characterized in that: The first crushing mechanism and the second crushing mechanism have the same structure. The first crushing mechanism includes a crushing roller that is rotatably disposed inside a protective cover. Multiple crushing tool mounting slots are evenly provided on the outer wall of the crushing roller. Each crushing tool mounting slot includes a first mounting slot. A second mounting slot is provided on both sides of the first mounting slot. Two third mounting slots are provided on both sides of the bottom of the second mounting slot. Each crushing tool mounting slot is provided with a multi-stage crushing tool. The multi-stage crushing tool includes a telescopic rod slidably disposed in a first mounting groove. A crushing blade is fixedly disposed on the top of the telescopic rod, and first lifting columns are fixedly disposed on both sides of the bottom. The two first lifting columns are fixedly disposed at the bottom of the first mounting groove. Guide holes adapted to the structure of the two first lifting columns are also opened on both sides of the bottom of the telescopic rod. The two first lifting columns are slidably disposed in the two guide holes respectively. A first return spring is slidably sleeved on the outer wall of the first lifting column and located between the first mounting groove and the telescopic rod.

6. The apparatus for recycling graphite anode material from waste lithium batteries according to claim 5, characterized in that: Side plates are fixedly installed on the outer wall of the crushing roller on both sides of each second mounting groove. A shearing pressure block is slidably installed between the two side plates. The bottom of the shearing pressure block is slidably installed in the second mounting groove at the corresponding position. Two second lifting columns are also fixedly installed at the bottom of the shearing pressure block. The two second lifting columns are slidably installed in the two third mounting grooves at the corresponding positions. A second return spring is slidably sleeved on the outer wall of the second lifting column between the second mounting groove and the shearing pressure block.

7. The equipment for recycling graphite anode material from waste lithium batteries according to claim 1, characterized in that: The secondary separation assembly includes a screening roller rotatably mounted on one side of the top of the support frame. A toothed ring is fixedly fitted on one side of the outer wall of the screening roller, and a screening gear meshes on one side of the toothed ring. A screening power shaft is fixedly mounted on one end of the screening gear. A third servo motor is also fixedly mounted on one side of the top of the support frame. The output shaft of the third servo motor is fixedly connected to one end of the screening power shaft. A graphite powder output pipe is also fixedly mounted inside the support frame and below the screening roller. The top opening area of ​​the graphite powder output pipe is larger than the horizontal projection area of ​​the secondary separation assembly.

8. The apparatus for recycling graphite anode material from waste lithium batteries according to claim 7, characterized in that: The inner wall of the screening roller is fixedly provided with hollowed-out spiral guide blades. A fixed air separator pipe is coaxially inserted inside the screening roller. Both ends of the fixed air separator pipe are fixedly installed on the support frame by support brackets and do not rotate with the screening roller. The pipe wall of the fixed air separator pipe is evenly opened with multiple sets of obliquely arranged air separator nozzles along the axial direction. The spray direction of the air separator nozzles is directly facing the area where the material is thrown when the screening roller rotates. The air inlet end of the fixed air separator pipe is connected to the exhaust pipes of the first negative pressure suction component and the second negative pressure suction component through pipelines, so as to introduce the positive pressure exhaust generated by the negative pressure suction into the interior of the screening roller to form a turbulent air curtain.

9. The equipment for recycling graphite anode material from waste lithium batteries according to claim 4, characterized in that: On the opposite sidewalls of the two first guide plates, several sets of dispersing lever assemblies are rotatably installed along the material falling direction. Each set of dispersing lever assemblies includes a rotating shaft and multiple flexible teeth evenly fixed on the outer wall of the rotating shaft. One end of each rotating shaft is fixedly fitted with a pneumatic impeller. The pneumatic impeller is directly opposite the airflow channel connecting the air duct and the graphite powder separation pipe. The high-speed airflow formed by negative pressure suction drives the pneumatic impeller to rotate, causing the flexible teeth to continuously sweep the material receiving surface of the first guide plate.

10. A method for recycling graphite anode material from waste lithium batteries, employing the equipment for recycling graphite anode material from waste lithium batteries as described in any one of claims 1-9, characterized in that: The method includes the following steps: Step 1, Material Feeding: The waste lithium battery graphite anode material is fed into the protective cover through the feeding hopper. The material falls by its own weight into the gap area between the rollers of the first crushing mechanism and the second crushing mechanism. Step 2, Roller Crushing and Separation: The graphite anode material is subjected to opposing roller crushing by the first crushing mechanism and the second crushing mechanism arranged in opposite directions, which simultaneously breaks the anode sheet and achieves the initial separation of graphite powder and copper foil matrix. Step 3, Kneading and Deep Peeling: The crushed negative electrode mixture falls to the first and second kneading rollers below by its own weight. The mixture is kneaded by the opposite rotation of the two kneading rollers, deeply peeling off the graphite powder adhering to the copper foil surface, and completing the further separation of graphite and copper foil. Step 4, negative pressure primary separation: During the crushing and kneading process, the first negative pressure suction component and the second negative pressure suction component, which are set on both sides of the crushing mechanism, generate suction negative pressure synchronously by relying on the transmission power of the crushing mechanism, and extract the dissociated graphite powder in real time, thus completing the primary material separation simultaneously. Step 5, Terminal Classification and Collection: The kneaded mixture is conveyed in a closed manner through the graphite copper foil fragment conveying pipe to the secondary separation component on the support frame. The secondary separation component performs terminal fine screening of the copper foil fragments to remove the residual graphite powder entrained in the copper foil fragments, and finally realizes the classification and collection of the two recyclable materials, copper foil and graphite powder.

Images