A method and apparatus for extracting lithium from waste lithium-ion batteries
By employing reduction roasting, carbonation leaching, cobalt removal, and thermal decomposition methods and apparatus, the problems of lengthy lithium recycling processes, low recovery rates, and low purity in lithium-ion battery recycling have been solved, achieving efficient and low-cost lithium recycling.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- CHONGQING HUAN LITHIUM RECYCLING TECHNOLOGY CO LTD
- Filing Date
- 2026-03-26
- Publication Date
- 2026-06-02
AI Technical Summary
In existing technologies, the lithium recycling process for lithium-ion batteries is lengthy, with low recovery rates and low purity. Furthermore, lithium is easily contaminated by sodium sulfate in traditional processes, affecting product purity.
Lithium is extracted using reduction roasting, carbonation leaching, cobalt removal, and thermal decomposition. A dedicated extraction device is used for efficient lithium recovery. The extraction device includes reduction roasting, carbonation leaching, cobalt removal, and thermal decomposition steps, and uses a stirring and scraper mechanism in the extraction device to clean lithium carbonate crystals.
It significantly shortens the lithium recycling process, improves the lithium recovery rate and purity, reduces the amount of external reducing agent used, lowers recycling costs, and enables the reuse of process water, thus reducing wastewater generation.
Smart Images
Figure CN122128540A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of battery recycling technology, and in particular to a method and apparatus for extracting lithium from waste lithium-ion batteries. Background Technology
[0002] Lithium-ion batteries have been widely used in mobile communications, laptops, portable tools and electric bicycles due to their outstanding advantages such as high voltage, high energy density, long cycle life, good safety and no memory effect.
[0003] Currently, the recycling process for spent lithium-ion batteries mainly focuses on recovering valuable metals such as cobalt, while lithium recovery generally suffers from low overall recovery rates and low product purity. Existing technologies typically employ a "back-end recycling" approach for lithium recovery. This involves pre-treating spent lithium-ion batteries, dissolving them in sulfuric acid, and removing impurities to recover cobalt, resulting in a lithium-containing sulfate solution (usually a mixture of sodium sulfate and lithium sulfate). Sodium carbonate is then added to this solution to precipitate and recover lithium carbonate.
[0004] However, this process has the following shortcomings: First, the lithium recovery process is lengthy, and lithium is dispersed and lost in multiple processes, resulting in a low direct recovery rate of lithium; second, the recovered lithium carbonate product is easily contaminated by sodium sulfate entrainment and there is a problem of sodium sulfate co-crystallization, which affects the purity of the product. Summary of the Invention
[0005] The purpose of this invention is to provide a method and apparatus for extracting lithium from waste lithium-ion batteries, aiming to solve the problems of lengthy lithium recycling processes, low recovery rates, and low purity in existing technologies.
[0006] To achieve the above objectives, the present invention provides a method for extracting lithium from waste lithium-ion batteries, comprising the following steps: S1: Take the battery active material obtained after stripping the current collector from waste lithium-ion batteries, and reduce and roast it to obtain reduced roasted material. S2: After carbonation leaching, the reduced roasted material is filtered to obtain carbonation leaching residue and carbonation leaching liquid; S3: The carbonation leachate is subjected to cobalt removal treatment, and after filtration, cobalt-removed slag and cobalt-removed solution are obtained. S4: The cobalt removal solution is heated and decomposed, and after filtration, a solid containing lithium carbonate and the decomposed liquid are obtained. The decomposed liquid is then recycled back to S2 as a leachate for reuse.
[0007] In step S1: The battery active material is a mixture of positive electrode active material and negative electrode carbonaceous material from waste lithium-ion batteries.
[0008] The preparation method of the mixture of positive electrode active material and negative electrode carbonaceous material from the waste lithium-ion battery is as follows: Waste lithium-ion batteries are discharged and disassembled to obtain battery cells. Then, the battery current collector of the battery cells is removed to obtain a mixture of positive electrode active material and negative electrode carbonaceous material from the waste lithium-ion batteries.
[0009] The present invention also provides a lithium extraction device from waste lithium-ion batteries, including a base, a heating vessel, a lifting mechanism, a top motor, a stirring shaft, a horizontal scraper, a reinforcing rod, a vertical scraper, and a cleaning mechanism; The heating vessel is fixedly mounted on the top of the base; the lifting mechanism is mounted on the top of the base; the top motor is fixedly mounted on the lifting mechanism; the stirring shaft is rotatably mounted on the lifting mechanism and fixedly connected to the output end of the top motor; the horizontal scraper is fixedly mounted on one side of the stirring shaft; the reinforcing rod is fixedly mounted on one side of the stirring shaft; the top end of the vertical scraper is fixedly connected to the end of the reinforcing rod away from the stirring shaft, and the bottom end of the vertical scraper is fixedly connected to the end of the horizontal scraper away from the stirring shaft; the cleaning mechanism is mounted on the base and is used to clean the lithium carbonate crystals adhering to the stirring shaft, the horizontal scraper, and the vertical scraper.
[0010] The lifting mechanism includes two hydraulic cylinders and a top plate; The two hydraulic cylinders are respectively fixedly mounted on the top of the base; the top plate is fixedly mounted on the top of the output end of the two hydraulic cylinders, and is used to fix the top motor and rotate the stirring shaft.
[0011] The cleaning mechanism includes a vertical drive component, a horizontal drive component, two first cleaning components, and a second cleaning component; The vertical drive component is disposed on the top of the base; the horizontal drive component is disposed on the top of the base; one of the first cleaning components is disposed on the vertical drive component, and the other of the first cleaning components is disposed on the horizontal drive component; the vertical drive component is used to drive the first cleaning component to clean the vertical scraper; the horizontal drive component is used to drive the first cleaning component to clean the horizontal scraper; the second cleaning component is used to clean the stirring shaft during the upward movement of the stirring shaft.
[0012] The vertical drive component includes a first bracket, a first guide rail, a first slider, a first lead screw, a first motor, and a first electric push rod. The first bracket is fixedly mounted on the top of the base; the first guide rail is fixedly mounted on the first bracket; the first slider is slidably mounted inside the first guide rail; the first lead screw is rotatably mounted inside the first guide rail and threadedly connected to the first slider; the first motor is fixedly mounted on the top of the first guide rail, and the output end of the first motor is fixedly connected to the first lead screw; the first electric push rod is fixedly mounted on the first slider, and the output end of the first electric push rod is used to fix the first cleaning component.
[0013] The lateral drive component includes a second bracket, a second guide rail, a second slider, a second lead screw, a second motor, and a second electric push rod. The second bracket is fixedly mounted on the top of the base; the second guide rail is fixedly mounted on the second bracket; the second slider is slidably mounted inside the second guide rail; the second lead screw is rotatably mounted inside the second guide rail and threadedly connected to the second slider; the second motor is fixedly mounted at one end of the second guide rail, and the output end of the second motor is fixedly connected to the second lead screw; the second electric push rod is fixedly mounted on the second slider, and the output end of the second electric push rod is used to fix the first cleaning component.
[0014] The first cleaning component includes a cleaning block, a mounting shaft, two support plates, a cleaning rod, and a torsion spring. The cleaning block has a first groove and a second groove at its end; the mounting shaft is fixedly installed in the first groove; the two support plates are rotatably mounted on the mounting shaft; one end of the cleaning rod is fixedly connected to the two support plates respectively, and the other end is located in the second groove; the torsion spring is sleeved on the mounting shaft.
[0015] The second cleaning component includes a third electric push rod, a mounting box, two clamping blocks, a bidirectional lead screw, and a third motor. The third electric push rod is fixedly mounted on one side of the second guide rail; the mounting box is fixedly mounted on the output end of the third electric push rod; the two clamping blocks are slidably mounted in the mounting box; the bidirectional lead screw is rotatably mounted in the mounting box and threadedly connected to the two clamping blocks; the third motor is fixedly mounted on one end of the mounting box, and the output end of the third motor is fixedly connected to the bidirectional lead screw.
[0016] This invention discloses a method and apparatus for extracting lithium from waste lithium-ion batteries. The method includes the following steps: S1: Taking the battery active material obtained after stripping the current collector from the waste lithium-ion battery, and performing reduction roasting on it to obtain reduced roasted material; S2: Filtering the reduced roasted material after carbonation leaching to obtain carbonation leaching residue and carbonation leaching solution; S3: Treating the carbonation leaching solution to remove cobalt, and obtaining cobalt-removed residue and cobalt-removed solution after filtration; S4: Heating and decomposing the cobalt-removed solution, and obtaining a solid containing lithium carbonate and a decomposed liquid after filtration. The decomposed liquid is recycled back to S2 as a leaching solution for reuse. This method solves the problems of lengthy lithium recycling processes, low recovery rates, and low purity in existing technologies. Attached Figure Description
[0017] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below.
[0018] Figure 1 This is a flowchart illustrating the first embodiment of the present invention.
[0019] Figure 2 This is a schematic diagram of the structure of the second embodiment of the present invention.
[0020] Figure 3 yes Figure 2 A magnified view of detail A.
[0021] Figure 4 This is a structural schematic diagram of the second embodiment of the present invention from another angle.
[0022] Figure 5 yes Figure 4 A magnified view of detail B.
[0023] Figure 6 This is a structural schematic diagram of the second embodiment of the present invention from another angle.
[0024] Figure 7 yes Figure 6 A magnified view of detail C.
[0025] Figure 8 This is a structural schematic diagram of the second embodiment of the present invention from another angle.
[0026] Figure 9 yes Figure 8 A magnified view of detail D.
[0027] Figure 10 This is a schematic diagram of the structure of the first cleaning component of the present invention.
[0028] Figure 11 This is a structural schematic diagram of the first cleaning component of the present invention from another angle.
[0029] 1-Base, 2-Heating vessel, 3-Lifting mechanism, 4-Top motor, 5-Stirring shaft, 6-Horizontal scraper, 7-Reinforcing rod, 8-Vertical scraper, 9-Cleaning mechanism, 31-Hydraulic cylinder, 32-Top plate, 91-Vertical drive component, 92-Horizontal drive component, 93-First cleaning component, 94-Second cleaning component, 911-First bracket, 912-First guide rail, 913-First slider, 914-First lead screw, 915-First motor, 916-First electric pusher Rod, 921-Second bracket, 922-Second guide rail, 923-Second slider, 924-Second lead screw, 925-Second motor, 926-Second electric push rod, 931-Cleaning block, 932-Mounting shaft, 933-Support plate, 934-Cleaning rod, 935-Torsion spring, 9311-First groove, 9312-Second groove, 941-Third electric push rod, 942-Mounting box, 943-Clamping block, 944-Bidirectional lead screw, 945-Third motor. Detailed Implementation
[0030] The first embodiment of this application is as follows: Please see Figure 1 ,in, Figure 1 This is a flowchart illustrating the first embodiment of the present invention.
[0031] This invention provides a method for extracting lithium from waste lithium-ion batteries: S1: Take the battery active material obtained after stripping the current collector from waste lithium-ion batteries, and reduce and roast it to obtain reduced roasted material. In this embodiment, the battery active material is a mixture of positive electrode active material and negative electrode carbonaceous material from waste lithium-ion batteries. The preparation method of the mixture is as follows: discharging and disassembling the waste lithium-ion batteries to obtain battery cells, and then removing the current collector from the battery cells to obtain the mixture of positive electrode active material and negative electrode carbonaceous material from the waste lithium-ion batteries. The reduction calcination includes: adding a reducing agent at 8-15% of the total mass of the battery active material, calcining at 700-800℃, and calcining for 1.5-2.5 hours.
[0032] S2: After carbonation leaching, the reduced roasted material is filtered to obtain carbonation leaching residue and carbonation leaching liquid; In this embodiment, the carbonation leaching includes: adding the reduced roasted material to water and introducing CO2 for stirring and leaching; or adding it to the leaching solution for carbonation leaching, with a leaching temperature ≤25℃, a leaching time of 3-4 hours, and a liquid-to-solid ratio of 12-18 mL:1 g.
[0033] S3: The carbonation leachate is subjected to cobalt removal treatment, and after filtration, cobalt-removed slag and cobalt-removed solution are obtained. In this embodiment, the cobalt removal temperature is 70–90°C, and the cobalt removal time is 20–40 minutes.
[0034] S4: The cobalt removal solution is heated and decomposed, and after filtration, a solid containing lithium carbonate and the decomposed liquid are obtained. The decomposed liquid is then recycled back to S2 as a leachate for reuse.
[0035] In this embodiment, the heating time is 1 to 1.5 hours and the heating temperature is 85 to 98°C. The core purpose is to decompose the lithium bicarbonate (LiHCO3) dissolved in the cobalt removal solution by heating, and convert it into insoluble lithium carbonate (Li2CO3) crystals that precipitate out.
[0036] This embodiment describes a method for extracting lithium from spent lithium-ion batteries. First, this method significantly shortens the overall lithium recycling process, effectively avoiding the dispersion and loss of lithium at multiple stages in traditional downstream recycling processes. It also fundamentally solves the problem of difficult separation of lithium sulfate and sodium sulfate in the later stages, thereby greatly improving the overall lithium recovery rate. Second, during the carbonation leaching process, cobalt in the leaching slurry can be efficiently purified and separated without the addition of any additional reagents, effectively avoiding the introduction of impurities and ensuring the purity of the final lithium carbonate product. Third, the decomposition liquid generated after heating and decomposition can be directly recycled back to the carbonation leaching step as the leaching liquid, realizing the reuse of process water and significantly reducing the generation and discharge of wastewater. Fourth, the battery active material separated from the current collector in this method can include the negative electrode carbonaceous material of spent lithium-ion batteries. This carbonaceous material can be fully utilized as a reducing agent during the reduction roasting process, thereby effectively reducing the amount of external reducing agent used and lowering the overall recycling cost. Through these methods, the problems of lengthy lithium recycling processes, low recovery rates, and low purity in existing technologies are solved.
[0037] The second embodiment of this application is as follows: Based on the first embodiment, please refer to Figures 2-11 ,in, Figure 2 This is a schematic diagram of the structure of the second embodiment of the present invention. Figure 3 yes Figure 2 A magnified view of detail A. Figure 4 This is a structural schematic diagram of the second embodiment of the present invention from another angle. Figure 5 yes Figure 4 A magnified view of detail B. Figure 6 This is a structural schematic diagram of the second embodiment of the present invention from another angle. Figure 7 yes Figure 6 A magnified view of detail C. Figure 8 This is a structural schematic diagram of the second embodiment of the present invention from another angle. Figure 9 yes Figure 8 A magnified view of detail D. Figure 10 This is a schematic diagram of the structure of the first cleaning component of the present invention. Figure 11 This is a structural schematic diagram of the first cleaning component of the present invention from another angle.
[0038] This invention provides a lithium extraction device from waste lithium-ion batteries, comprising a base 1, a heating vessel 2, a lifting mechanism 3, a top motor 4, a stirring shaft 5, a horizontal scraper 6, a reinforcing rod 7, a vertical scraper 8, and a cleaning mechanism 9; the lifting mechanism 3 includes two hydraulic cylinders 31 and a top plate 32; the cleaning mechanism 9 includes a vertical drive component 91, a horizontal drive component 92, two first cleaning components 93, and a second cleaning component 94; the vertical drive component 91 includes a first bracket 911, a first guide rail 912, a first slider 913, a first lead screw 914, a first motor 915, and a first electric push rod. 916; The transverse drive component 92 includes a second bracket 921, a second guide rail 922, a second slider 923, a second lead screw 924, a second motor 925, and a second electric push rod 926; The first cleaning component 93 includes a cleaning block 931, a mounting shaft 932, two support plates 933, a cleaning rod 934, and a torsion spring 935; The end of the cleaning block 931 is provided with a first groove 9311 and a second groove 9312; The second cleaning component 94 includes a third electric push rod 941, a mounting box 942, two clamping blocks 943, a bidirectional lead screw 944, and a third motor 945.
[0039] Furthermore, the heating vessel 2 is fixedly mounted on the top of the base 1; the lifting mechanism 3 is mounted on the top of the base 1; the top motor 4 is fixedly mounted on the lifting mechanism 3; the stirring shaft 5 is rotatably mounted on the lifting mechanism 3 and fixedly connected to the output end of the top motor 4; the horizontal scraper 6 is fixedly mounted on one side of the stirring shaft 5; the reinforcing rod 7 is fixedly mounted on one side of the stirring shaft 5; the top end of the vertical scraper 8 is fixedly connected to the end of the reinforcing rod 7 away from the stirring shaft 5, and the bottom end of the vertical scraper 8 is fixedly connected to the end of the horizontal scraper 6 away from the stirring shaft 5; the cleaning mechanism 9 is mounted on the base 1 and is used to clean the lithium carbonate crystals adhering to the stirring shaft 5, the horizontal scraper 6, and the vertical scraper 8.
[0040] In this embodiment, the heating vessel 2 is used to heat and decompose the cobalt removal solution by applying electricity, and after filtration, a solid containing lithium carbonate and the decomposed liquid are obtained. The top motor 4 is used to drive the stirring shaft 5 to rotate. The stirring shaft 5, the horizontal scraper 6, the vertical scraper 8, and the reinforcing rod 7 together form a stirring mechanism and a scraping mechanism, which are used to stir during the heating and decomposition of the cobalt removal solution. At the same time, the vertical scraper 8 scrapes the inner wall of the heating vessel 2 to prevent lithium carbonate crystals from adhering. The horizontal scraper 6 scrapes the inner bottom wall of the heating vessel 2 to prevent lithium carbonate crystals from adhering. However, lithium carbonate crystals will also adhere to the stirring shaft 5, the horizontal scraper 6, and the vertical scraper 8. Therefore, after use, the lifting mechanism 3 drives the whole structure to rise, and the cleaning mechanism 9 cleans off the lithium carbonate crystals adhering to the stirring shaft 5, the horizontal scraper 6, and the vertical scraper 8. The horizontal scraper 6 and the vertical scraper 8 have the same shape, only different lengths.
[0041] Furthermore, the two hydraulic cylinders 31 are respectively fixedly mounted on the top of the base 1; the top plate 32 is fixedly mounted on the top of the output end of the two hydraulic cylinders 31, for fixing the top motor 4 and rotating the stirring shaft 5.
[0042] In this embodiment, the two hydraulic cylinders 31 are used to drive the top plate 32 to rise and fall.
[0043] Furthermore, the vertical drive member 91 is disposed on the top of the base 1; the horizontal drive member 92 is disposed on the top of the base 1; one of the first cleaning members 93 is disposed on the vertical drive member 91, and the other first cleaning member 93 is disposed on the horizontal drive member 92; the vertical drive member 91 is used to drive the first cleaning member 93 to clean the vertical scraper 8; the horizontal drive member 92 is used to drive the first cleaning member 93 to clean the horizontal scraper 6; the second cleaning member 94 is used to clean the stirring shaft 5 during the upward movement of the stirring shaft 5.
[0044] In this embodiment, when cleaning is required, after the top plate 32 moves to its highest position, the vertical drive member 91 drives the first cleaning member 93 to clean the lithium carbonate crystals adhering to the vertical scraper 8; the horizontal drive member 92 drives the first cleaning member 93 to clean the lithium carbonate crystals adhering to the horizontal scraper 6; and the cleaning of the lithium carbonate crystals on the stirring shaft 5 occurs during the upward movement of the stirring shaft 5, at which point the second cleaning member 94 completes the cleaning of the lithium carbonate crystals on the stirring shaft 5.
[0045] Furthermore, the first bracket 911 is fixedly mounted on the top of the base 1; the first guide rail 912 is fixedly mounted on the first bracket 911; the first slider 913 is slidably mounted inside the first guide rail 912; the first lead screw 914 is rotatably mounted inside the first guide rail 912 and threadedly connected to the first slider 913; the first motor 915 is fixedly mounted on the top of the first guide rail 912, and the output end of the first motor 915 is fixedly connected to the first lead screw 914; the first electric push rod 916 is fixedly mounted on the first slider 913, and the output end of the first electric push rod 916 is used to fix the first cleaning component 93.
[0046] In this embodiment, the first motor 915 drives the first lead screw 914 to rotate, and the first lead screw 914 drives the first slider 913 to slide vertically along the first guide rail 912, which ultimately drives the first cleaning member 93 at the end to move vertically. At the same time, the first electric push rod 916 can also drive the first cleaning member 93 to move laterally.
[0047] Furthermore, the second bracket 921 is fixedly mounted on the top of the base 1; the second guide rail 922 is fixedly mounted on the second bracket 921; the second slider 923 is slidably mounted inside the second guide rail 922; the second lead screw 924 is rotatably mounted inside the second guide rail 922 and threadedly connected to the second slider 923; the second motor 925 is fixedly mounted on one end of the second guide rail 922, and the output end of the second motor 925 is fixedly connected to the second lead screw 924; the second electric push rod 926 is fixedly mounted on the second slider 923, and the output end of the second electric push rod 926 is used to fix the first cleaning component 93.
[0048] In this embodiment, the second motor 925 drives the second lead screw 924 to rotate, and the second lead screw 924 drives the second slider 923 to slide laterally along the second guide rail 922, ultimately causing the first cleaning component 93 at its end to move laterally. Simultaneously, the second electric push rod 926 can also cause the first cleaning component 93 to move vertically. The output end of the second electric push rod 926 is fixedly mounted on the first cleaning component 93 via a right-angle adapter rod.
[0049] Furthermore, the cleaning block 931 has a first groove 9311 and a second groove 9312 at its end; the mounting shaft 932 is fixedly disposed in the first groove 9311; the two support plates 933 are rotatably disposed on the mounting shaft 932; one end of the cleaning rod 934 is fixedly connected to the two support plates 933 respectively, and the other end is located in the second groove 9312; the torsion spring 935 is sleeved on the mounting shaft 932.
[0050] In this embodiment, the inner shape of the cleaning block 931 is adapted to the cross-section of the horizontal scraper 6 and the vertical scraper 8, so that it can fit snugly for scraping and cleaning; the torsion spring 935 always provides a torsional force to the cleaning rod 934, so that the other end of the cleaning rod 934 is always located in the second groove 9312; like Figure 1 As shown: When cleaning the vertical scraper bar 8, the cleaning block 931 first moves to the top of the vertical scraper bar 8 and aligns it, then moves down. During the downward movement, the cleaning bar 934 is blocked and pushed by the reinforcing rod 7. The cleaning bar 934 rotates 90 degrees along the mounting shaft 932, and the cleaning block 931 can then smoothly fit onto the vertical scraper bar 8. After the cleaning block 931 moves down a certain distance, the torsion spring 935 rotates the cleaning bar 934 back to its original position, and the cleaning block 931 and the cleaning bar 934 surround the vertical scraper bar 8. Then it moves downwards, and the two work together to scrape off the adhering lithium carbonate crystals; as it continues to move downwards to clean, at the end, the cleaning rod 934 is blocked by the horizontal scraper 6 and pushed, rotating 90 degrees, and the cleaning block 931 moves downwards smoothly, completing the cleaning of the last part of the vertical scraper 8. After moving downwards and getting away from the vertical scraper 8 for a certain distance, the torsion spring 935 rotates and resets the cleaning rod 934, and then the whole thing moves laterally again, moving out from under the vertical scraper 8. Finally, the whole thing moves up to the top and resets, waiting for the next use; When cleaning the transverse scraper 6, the cleaning block 931 first moves to one end of the transverse scraper 6 and aligns it, then moves laterally. During this movement, the cleaning rod 934 is blocked and pushed by the stirring shaft 5. The cleaning rod 934 rotates 90 degrees along the mounting shaft 932, allowing the cleaning block 931 to smoothly fit onto the transverse scraper. After continuing to move a certain distance, the cleaning rod 934 rotates back to its original position. The cleaning block 931 and the cleaning rod 934 surround the transverse scraper 6, and then the block moves backward, scraping away the lithium carbonate crystals at the top of the transverse scraper 6 for the distance before the cleaning rod 934 was reset. After the cleaning rod 934 contacts the stirring shaft 5, it continues to move forward. The cleaning block 931 and the cleaning rod 934 cooperate to move laterally and scrape off the lithium carbonate crystals on the horizontal scraper 6. After moving laterally to the end, the cleaning rod 934 is blocked by the vertical scraper 8 and rotates 90 degrees. The cleaning block 931 can then move laterally smoothly to complete the cleaning of the last part of the horizontal scraper 6. After moving laterally a certain distance away, the cleaning rod 934 returns to its original position. Then the cleaning block 931 moves down and is no longer aligned with the horizontal scraper 6. Finally, it moves laterally from below the horizontal scraper 6 to return to its original position. It should be noted that because the solution inside the heating vessel 2 is not full, the upper part of the stirring shaft 5, the entire reinforcing rod 7, and the upper part of the vertical scraper 8 will not come into contact with the solution, and therefore will not allow crystals to adhere.
[0051] Furthermore, the third electric push rod 941 is fixedly mounted on one side of the second guide rail 922; the mounting box 942 is fixedly mounted on the output end of the third electric push rod 941; the two clamping blocks 943 are slidably mounted in the mounting box 942; the bidirectional lead screw 944 is rotatably mounted in the mounting box 942 and threadedly connected to the two clamping blocks 943; the third motor 945 is fixedly mounted on one end of the mounting box 942, and the output end of the third motor 945 is fixedly connected to the bidirectional lead screw 944.
[0052] In this embodiment, the third motor 945 drives the bidirectional lead screw 944 to rotate, thereby driving the two clamping blocks 943 to move in opposite directions to separate or close. like Figure 1 In this state, if the stirring shaft 5 is to be moved downwards for use, the two clamping blocks 943 must first separate to avoid obstructing the downward movement of the reinforcing rod 7; after use, the stirring shaft 5 moves upwards, and after the reinforcing rod 7 moves upwards past the two clamping blocks 943, the two clamping blocks 943 immediately close together, and then as the stirring shaft 5 moves upwards, the two clamping blocks 943 will continuously clean the lithium carbonate crystals adhering to the stirring shaft 5; It should be noted that when cleaning the transverse scraper 6, the third electric push rod 941 should first move the two clamping blocks 943 upwards a certain distance to avoid obstructing the cleaning block 931.
[0053] The lithium extraction device for waste lithium-ion batteries described in this embodiment prevents lithium carbonate crystals from adhering to the inner wall of the heating vessel 2 during use. After use, it can also clean the lithium carbonate crystals adhering to the stirring shaft 5, the horizontal scraper 6, and the vertical scraper 8. It should be noted that when the horizontal scraper 6 moves down to contact the bottom wall of the heating vessel 2, the reinforcing rod 7 moves to a position flush with the top of the heating vessel 2, and the vertical scraper 8 contacts the inner wall of the heating vessel 2.
[0054] The above-disclosed embodiments are merely one or more preferred embodiments of this application and should not be construed as limiting the scope of this application. Those skilled in the art can understand that all or part of the processes for implementing the above embodiments and equivalent changes made in accordance with the claims of this application still fall within the scope of this application.
Claims
1. A method for extracting lithium from waste lithium-ion batteries, characterized in that, Includes the following steps: S1: Take the battery active material obtained after stripping the current collector from waste lithium-ion batteries, and reduce and roast it to obtain reduced roasted material. S2: After carbonation leaching, the reduced roasted material is filtered to obtain carbonation leaching residue and carbonation leaching liquid; S3: The carbonation leachate is subjected to cobalt removal treatment, and after filtration, cobalt-removed slag and cobalt-removed solution are obtained. S4: The cobalt removal solution is heated and decomposed, and after filtration, a solid containing lithium carbonate and the decomposed liquid are obtained. The decomposed liquid is then recycled back to S2 as a leachate for reuse.
2. The method for extracting lithium from waste lithium-ion batteries as described in claim 1, characterized in that, In step S1: The battery active material is a mixture of positive electrode active material and negative electrode carbonaceous material from waste lithium-ion batteries.
3. The method for extracting lithium from waste lithium-ion batteries as described in claim 2, characterized in that, The preparation method of the mixture of positive electrode active material and negative electrode carbonaceous material from the waste lithium-ion battery is as follows: Waste lithium-ion batteries are discharged and disassembled to obtain battery cells. Then, the battery current collector of the battery cells is removed to obtain a mixture of positive electrode active material and negative electrode carbonaceous material from the waste lithium-ion batteries.
4. A lithium extraction apparatus for waste lithium-ion batteries, applied to the lithium extraction method for waste lithium-ion batteries as described in claim 1; characterized in that, It includes a base, heating vessel, lifting mechanism, top motor, stirring shaft, horizontal scraper, reinforcing rod, vertical scraper, and cleaning mechanism; The heating vessel is fixedly mounted on the top of the base; the lifting mechanism is mounted on the top of the base; the top motor is fixedly mounted on the lifting mechanism; the stirring shaft is rotatably mounted on the lifting mechanism and fixedly connected to the output end of the top motor; the horizontal scraper is fixedly mounted on one side of the stirring shaft; the reinforcing rod is fixedly mounted on one side of the stirring shaft; the top end of the vertical scraper is fixedly connected to the end of the reinforcing rod away from the stirring shaft, and the bottom end of the vertical scraper is fixedly connected to the end of the horizontal scraper away from the stirring shaft; the cleaning mechanism is mounted on the base and is used to clean the lithium carbonate crystals adhering to the stirring shaft, the horizontal scraper, and the vertical scraper.
5. The lithium extraction device from waste lithium-ion batteries as described in claim 4, characterized in that, The lifting mechanism includes two hydraulic cylinders and a top plate; The two hydraulic cylinders are respectively fixedly mounted on the top of the base; the top plate is fixedly mounted on the top of the output end of the two hydraulic cylinders, and is used to fix the top motor and rotate the stirring shaft.
6. The lithium extraction device from waste lithium-ion batteries as described in claim 5, characterized in that, The cleaning mechanism includes a vertical drive component, a horizontal drive component, two first cleaning components, and a second cleaning component; The vertical drive component is disposed on the top of the base; the horizontal drive component is disposed on the top of the base; one of the first cleaning components is disposed on the vertical drive component, and the other of the first cleaning components is disposed on the horizontal drive component; the vertical drive component is used to drive the first cleaning component to clean the vertical scraper; the horizontal drive component is used to drive the first cleaning component to clean the horizontal scraper; the second cleaning component is used to clean the stirring shaft during the upward movement of the stirring shaft.
7. The lithium extraction device from waste lithium-ion batteries as described in claim 6, characterized in that, The vertical drive component includes a first bracket, a first guide rail, a first slider, a first lead screw, a first motor, and a first electric push rod; The first bracket is fixedly mounted on the top of the base; the first guide rail is fixedly mounted on the first bracket; the first slider is slidably mounted inside the first guide rail; the first lead screw is rotatably mounted inside the first guide rail and threadedly connected to the first slider; the first motor is fixedly mounted on the top of the first guide rail, and the output end of the first motor is fixedly connected to the first lead screw; the first electric push rod is fixedly mounted on the first slider, and the output end of the first electric push rod is used to fix the first cleaning component.
8. The method and apparatus for extracting lithium from waste lithium-ion batteries as described in claim 7, characterized in that, The lateral drive component includes a second bracket, a second guide rail, a second slider, a second lead screw, a second motor, and a second electric push rod; The second bracket is fixedly mounted on the top of the base; the second guide rail is fixedly mounted on the second bracket; the second slider is slidably mounted inside the second guide rail; the second lead screw is rotatably mounted inside the second guide rail and threadedly connected to the second slider; the second motor is fixedly mounted at one end of the second guide rail, and the output end of the second motor is fixedly connected to the second lead screw; the second electric push rod is fixedly mounted on the second slider, and the output end of the second electric push rod is used to fix the first cleaning component.
9. The lithium extraction device from waste lithium-ion batteries as described in claim 8, characterized in that, The first cleaning component includes a cleaning block, a mounting shaft, two support plates, a cleaning rod, and a torsion spring; The cleaning block has a first groove and a second groove at its end; the mounting shaft is fixedly installed in the first groove; the two support plates are rotatably mounted on the mounting shaft; one end of the cleaning rod is fixedly connected to the two support plates respectively, and the other end is located in the second groove; the torsion spring is sleeved on the mounting shaft.
10. The lithium extraction device from waste lithium-ion batteries as described in claim 9, characterized in that, The second cleaning component includes a third electric push rod, a mounting box, two clamping blocks, a bidirectional lead screw, and a third motor; The third electric push rod is fixedly mounted on one side of the second guide rail; the mounting box is fixedly mounted on the output end of the third electric push rod; the two clamping blocks are slidably mounted in the mounting box; the bidirectional lead screw is rotatably mounted in the mounting box and threadedly connected to the two clamping blocks; the third motor is fixedly mounted on one end of the mounting box, and the output end of the third motor is fixedly connected to the bidirectional lead screw.