Recycling method and system for positive electrode material of waste lithium iron phosphate battery

Abstract

The invention provides a method and a system for recycling a positive electrode material of a waste lithium iron phosphate battery, and relates to the technical field of regeneration of useful components of the waste lithium iron phosphate battery, the method comprises the following steps: stripping a positive plate from the waste lithium iron phosphate battery, the positive plate comprising an aluminum foil and a positive electrode material bonded on the aluminum foil; two parts of the aluminum foil are respectively clamped; the area between the two clamped parts of the aluminum foil is moved rightwards; scraping and collecting the positive electrode material on the aluminum foil; extracting lithium ions from the positive electrode material; preparing a positive electrode material of the lithium iron phosphate battery by utilizing lithium ions; the scraper moves in the width direction of the aluminum foil, and the moving path of the scraper comprises a backward path and a forward path. The system applies the method. The scraper can continuously scrape the positive electrode materials at different positions of the aluminum foil on the premise that the aluminum foil is well positioned, and the whole scraping process is efficient and stable.

Description

Technical Field

[0001] The present invention relates to the technical field of regenerating useful parts of waste lithium iron phosphate batteries, and in particular to a method and system for recycling positive electrode materials of waste lithium iron phosphate batteries. Background Art

[0002] The positive electrode of lithium iron phosphate battery includes aluminum foil and positive electrode material (lithium iron phosphate (LiFePO4), also called black powder). The positive electrode material is bonded to the surface of the aluminum foil, and the positive electrode material contains lithium. Lithium iron phosphate (LiFePO4) battery has the characteristics of high safety, good stability, economy and environmental protection, and is widely used in new energy vehicles and energy storage fields.

[0003] With the increasing number of waste lithium batteries, it has become a consensus in the industry to accelerate the development of recycling technology for waste lithium batteries. Therefore, it is necessary to design a recycling method and system for waste lithium iron phosphate battery positive electrode materials to recycle the lithium element of waste lithium iron phosphate battery positive electrode materials for the preparation of new lithium iron phosphate battery positive electrode materials, thereby promoting the sustainable development of the lithium battery industry. Summary of the invention

[0004] In view of the above situation, the present invention provides a method and system for recycling positive electrode materials of waste lithium iron phosphate batteries, which can recycle positive electrode materials of waste lithium iron phosphate batteries and is conducive to promoting the sustainable development of the lithium battery industry.

[0005] To achieve the above object, the present invention provides the following technical solutions: In a first aspect, the present invention provides a method for recycling waste lithium iron phosphate battery positive electrode materials, comprising: Step S1, peeling off a positive electrode sheet from a waste lithium iron phosphate battery, wherein the positive electrode sheet comprises an aluminum foil and a positive electrode material bonded to the aluminum foil; Step S2, clamping two parts of the aluminum foil at a first clamping station and a second clamping station respectively, wherein the first clamping station and the second clamping station are spaced apart along the length direction of the aluminum foil; Step S3, moving the area between the two clamped parts of the aluminum foil to the right to the scraping station; Step S4, scraping the positive electrode material on the aluminum foil along the width direction of the aluminum foil and collecting it; Step S5, releasing the clamping of the aluminum foil; Step S6, repeating steps S2 to S5 to continuously recover the positive electrode material on the aluminum foil; Step S7, extracting lithium ions from the positive electrode material obtained in step S4; Step S8, using the lithium ions obtained in step S7 to prepare a new positive electrode material for a lithium iron phosphate battery; Among them, the scraping station is provided with a scraper, and the scraper moves along the width direction of the aluminum foil. The moving path of the scraper includes a backward path and a forward path. The scraper moves in a direction opposite to the backward path to form the forward path. The scraper moves cyclically along the backward path and the forward path.

[0006] In some embodiments of the present invention, the backward path includes a first backward path, a second backward path, a third backward path, a fourth backward path, and a fifth backward path that are connected in sequence; The forward path includes a first forward path, a second forward path, a third forward path, a fourth forward path, and a fifth forward path which are connected in sequence; The first backward path overlaps with the fifth forward path and is in the opposite direction, the second backward path overlaps with the fourth forward path and is in the opposite direction, the third backward path overlaps with the third forward path and is in the opposite direction, the fourth backward path overlaps with the second forward path and is in the opposite direction, and the fifth backward path overlaps with the first forward path and is in the opposite direction; The lengths of the third backward path and the third forward path are greater than or equal to the width of the aluminum foil; When the scraper moves along the first backward path, the first clamping mechanism and the second clamping mechanism clamp two parts of the aluminum foil at the first clamping station and the second clamping station respectively; when the scraper moves along the second backward path, the area between the two clamped parts of the aluminum foil is moved rightward to the scraping station; when the scraper moves along the third backward path, the first clamping mechanism and the second clamping mechanism maintain the clamping limit of the aluminum foil, so that the aluminum foil is fixed at the current position, so that the positive electrode material on the aluminum foil can be scraped off by the scraper; when the scraper moves along the fourth backward path, the aluminum foil is released; when the scraper moves along the fifth backward path, the first clamping mechanism and the second clamping mechanism move leftward and reset; When the scraper moves forward along the first path, the other two parts of the aluminum foil are clamped at the first clamping station and the second clamping station by the first clamping mechanism and the second clamping mechanism respectively; when the scraper moves forward along the second path, the area between the other two clamped parts of the aluminum foil is moved right to the scraping station; when the scraper moves forward along the third path, the first clamping mechanism and the second clamping mechanism maintain the clamping limit of the aluminum foil, so that the aluminum foil is fixed in the current position, so as to facilitate the scraping of the positive electrode material on the aluminum foil by the scraper; when the scraper moves forward along the fourth path, the aluminum foil is released from the clamping; when the scraper moves forward along the fifth path, the first clamping mechanism and the second clamping mechanism move left and reset.

[0007] In some embodiments of the present invention, step S7 includes: Step S71, pressing the positive electrode material of step S6 into a sheet material, wherein a plurality of holes are distributed on the sheet material; Step S72: Use the sheet material as the cathode of the electrolytic cell, use the carbon rod as the anode of the electrolytic cell, and use electrolytic reduction to leach lithium ions into the electrolyte of the electrolytic cell.

[0008] In some embodiments of the present invention, a plurality of holes are distributed on the sheet material.

[0009] In a second aspect, the present invention provides a system for recycling waste lithium iron phosphate battery positive electrode materials, comprising: A support platform, with the first clamping station and the second clamping station spaced apart along its length direction; A first clamping mechanism, disposed at the first clamping station; A second clamping mechanism is arranged at the second clamping station; the first clamping mechanism and the second clamping mechanism are respectively used to clamp two parts of the aluminum foil; the first clamping mechanism and the second clamping mechanism can be synchronously moved left or right; A scraping mechanism, comprising the scraper; The material receiving mechanism comprises a material receiving hopper arranged below the support platform for collecting positive electrode materials.

[0010] In some embodiments of the present invention, two lifting blocks are provided on the upper side of the scraper, and the lifting blocks are slidably connected to guide rods, and the axes of the guide rods are arranged along the width direction of the support platform.

[0011] In some embodiments of the present invention, the first clamping mechanism comprises: First vertical board; A first support plate is fixed on the first vertical plate, a first groove is formed on the support platform, a lower side of the first support plate is in sliding contact with a bottom of the first groove, and an upper side of the first support plate is in contact with a lower side of the aluminum foil; A first clamping plate, located above the first supporting plate and longitudinally slidably connected to the first vertical plate, wherein the lower side of the first clamping plate can contact the upper side of the aluminum foil; A first lifting ring, one end of which is connected to the first clamping plate and the other end of which is connected to the first crossbar; A first cross bar, one end of which is connected to the guide plate and the other end of which is connected to the lifting block; the lifting block can drive the first cross bar to move forward and backward, and the first cross bar can move left and right and up and down relative to the lifting block; The guide plate is fixedly arranged on the support platform; the guide plate is provided with a guide track for guiding the first cross bar to move up and down or left and right.

[0012] In some embodiments of the present invention, the second clamping mechanism comprises: The second vertical board; A second support plate is fixed on the second vertical plate, a second groove is formed on the support platform, a lower side of the second support plate is in sliding contact with a bottom of the second groove, and an upper side of the second support plate is in contact with a lower side of the aluminum foil; A second clamping plate is located above the second supporting plate and is longitudinally slidably connected to the second vertical plate, and the lower side of the second clamping plate can contact the upper side of the aluminum foil; A second lifting ring, one end of which is connected to the second clamping plate and the other end of which is connected to the second cross bar; One end of the second crossbar is connected to the first crossbar; the second crossbar moves with the first crossbar.

[0013] In some embodiments of the present invention, it further comprises: A fixing frame, fixedly arranged, the fixing frame is T-shaped, and an air inlet hole is arranged on the vertical portion of the fixing frame; An air supply pipe is connected to the air inlet and is used to supply a hot air flow at an angle of 45° to 55° to the air inlet; A movable enclosure is movably arranged to move left and right, and the movable enclosure is slidably connected to the fixed frame. The movable enclosure can define a space together with the fixed frame to form a cavity, and the cavity can be connected to the receiving hopper; an extension rod is provided on one side of the movable enclosure, and the extension rod is located in the cavity and can block the air inlet.

[0014] In some embodiments of the present invention, it further comprises: A flattening station is arranged on the left side of the first clamping station and the second clamping station, and the width of the area where the support platform is located at the flattening station is slightly smaller than the width of the aluminum foil; A plurality of nozzles connected to the air supply pipe are evenly arranged along the width direction of the support platform and disposed obliquely above the leveling station, and the nozzles spray obliquely downward toward the leveling station.

[0015] The embodiments of the present invention have at least the following advantages or beneficial effects: While the scraper is moving in a cycle along the backward path and the forward path, it can continuously scrape the positive electrode material at different positions of the aluminum foil under the premise of good positioning of the aluminum foil. The entire scraping process is efficient and stable, which is conducive to ensuring the recovery efficiency of the positive electrode material.

[0016] Other features and advantages of the present invention will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by practicing the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0018] Figure 1 Schematic diagram of the backward path and the forward path; Figure 2 It is a schematic diagram of the structure of the separation device and the pressing device; Figure 3 for Figure 2 A partial enlarged view of position A in the middle; Figure 4 for Figure 2 and Figure 3 The structural diagram of the guide rail located on the right side of the guide plate, Figure 4 The direction of the middle arrow is the moving direction of the first crossbar.

[0019] icon: 11-first clamping station, 12-second clamping station, 13-scraping station, 14-scraper, 15-aluminum foil, 21-first backward path, 22-second backward path, 23-third backward path, 24-fourth backward path, 25-fifth backward path, 26-first forward path, 27-second forward path, 28-third forward path, 29-fourth forward path, 31-fifth forward path, 41- support platform, 42-first clamping mechanism, 421-first vertical plate, 422-first supporting plate, 423-first clamping plate, 424-first lifting ring, 425-first cross bar, 426-guide plate, 43-second clamping mechanism, 431-second vertical plate, 432-second supporting plate, 433-second clamping plate, 434-second cross bar, 441-lifting block, 442-guide rod, 443-moving block, 444-spring, 451- receiving hopper, 51-rear downward pressing guide rail, 52-rear rightward moving guide rail, 53-rear holding guide rail, 54-rear upward moving guide rail, 55-rear leftward moving guide rail, 56-front downward pressing guide rail, 57-front rightward moving guide rail, 58-front holding guide rail, 59-front upward moving guide rail, 61-front leftward moving guide rail, 62-upward transfer guide rail, 63-downward transfer guide rail, 64- cavity, 65- extension rod, 66- air inlet, 67- fixing frame, 68- air supply pipe, 69- movable enclosure, 71-leveling station, 72-nozzle head. DETAILED DESCRIPTION

[0020] In the following, only some exemplary embodiments are briefly described. As those skilled in the art can realize, the described embodiments can be modified in various different ways without departing from the spirit or scope of the embodiments of the present invention.

[0021] In the description of the embodiments of the present invention, it should be understood that the terms "longitudinal", "lateral", "length", "width", "up", "down", "front", "back", "left", "right", "bottom", "inside", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the embodiments of the present invention and simplifying the description, rather than indicating or implying that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the embodiments of the present invention.

[0022] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the embodiments of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0023] In the embodiments of the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral one; it can be directly connected, or indirectly connected through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of the present invention can be understood according to specific circumstances.

[0024] The embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0025] Example

[0026] First, see Figure 1 This embodiment provides a method for recycling waste lithium iron phosphate battery positive electrode materials, comprising the following steps: Step S1, peeling off the positive electrode sheet from the waste lithium iron phosphate battery, the positive electrode sheet comprising an aluminum foil 15 and a positive electrode material bonded to the aluminum foil 15.

[0027] Step S2: clamp two parts of the aluminum foil 15 at the first clamping station 11 and the second clamping station 12 respectively, and the first clamping station 11 and the second clamping station 12 clamp two parts of the aluminum foil 15 along the length direction ( Figure 1 (left and right directions as shown) interval settings.

[0028] Step S3, the area between the two clamped parts of the aluminum foil 15 is moved rightward to the scraping station 13. The first clamping station 11, the second clamping station 12, and the scraping station 13 belong to the set area, and their positions remain unchanged.

[0029] Step S4: along the width direction of the aluminum foil 15 ( Figure 1 The positive electrode material on the aluminum foil 15 is scraped off and collected; Step S5, releasing the clamping of the aluminum foil 15; Step S6, repeat the above steps S2 to S5; Step S7, extracting lithium ions from the positive electrode material obtained in step S4; Step S8, using the lithium ions obtained in step S7 to prepare a new positive electrode material for a lithium iron phosphate battery; In a specific implementation scenario, the above steps S2 to S6 are implemented in the following manner: like Figure 1 As shown, the scraping station 13 is provided with a scraper 14, and the scraper 14 moves along the width direction of the aluminum foil 15. The moving path of the scraper 14 includes a backward path and a forward path. The scraper 14 moves in the direction opposite to the backward path to form a forward path, and the scraper 14 moves cyclically along the backward path and the forward path; specifically, the backward path includes a backward first path 21, a backward second path 22, a backward third path 23, a backward fourth path 24, and a backward fifth path 25 that are sequentially connected; the forward path includes a forward first path 26, a forward first path 27, and a forward second path 28 that are sequentially connected. The first path 27, the third path 28, the fourth path 29 and the fifth path 31 are arranged forward, wherein the first backward path 21 overlaps with the fifth forward path 31 and is in the opposite direction, the second backward path 22 overlaps with the fourth forward path 29 and is in the opposite direction, the third backward path 23 overlaps with the third forward path 28 and is in the opposite direction, the fourth backward path 24 overlaps with the second forward path 27 and is in the opposite direction, and the fifth backward path 25 overlaps with the first forward path 26 and is in the opposite direction; the lengths of the third backward path 23 and the third forward path 28 are greater than or equal to the width of the aluminum foil 15.

[0030] When the scraper 14 moves along the first backward path 21, the first clamping mechanism 42 and the second clamping mechanism 43 clamp two parts of the aluminum foil 15 at the first clamping station 11 and the second clamping station 12 respectively; when the scraper 14 moves along the second backward path 22, the area between the two clamped parts of the aluminum foil 15 is moved right to the scraping station 13; when the scraper 14 moves along the third backward path 23, the first clamping mechanism 42 and the second clamping mechanism 43 maintain the clamping limit of the aluminum foil 15, so that the aluminum foil 15 is fixed at the current position, so that the positive electrode material on the aluminum foil 15 can be scraped off by the scraper 14; when the scraper 14 moves along the fourth backward path 24, the aluminum foil 15 is released; when the scraper 14 moves along the fifth backward path 25, the first clamping mechanism 42 and the second clamping mechanism 43 move left and reset; When the knife 14 moves along the first forward path 26, the other two parts of the aluminum foil 15 are clamped at the first clamping station 11 and the second clamping station 12 by the first clamping mechanism 42 and the second clamping mechanism 43 respectively; when the scraper 14 moves along the second forward path 27, the area between the other two clamped parts of the aluminum foil 15 is moved right to the scraping station 13; when the scraper 14 moves along the third forward path 28, the first clamping mechanism 42 and the second clamping mechanism 43 maintain the clamping limit of the aluminum foil 15, so that the aluminum foil 15 is fixed in the current position, so that the positive electrode material on the aluminum foil 15 can be scraped off by the scraper 14; when the scraper 14 moves along the fourth forward path 29, the clamping of the aluminum foil 15 is released; when the scraper 14 moves along the fifth forward path 31, the first clamping mechanism 42 and the second clamping mechanism 43 move left and reset.

[0031] During the circular movement along the backward path and the forward path, the scraper 14 can continuously scrape the positive electrode material at different positions of the aluminum foil 15 under the premise of good positioning of the aluminum foil 15. The entire scraping process is efficient and stable, which is conducive to ensuring the recovery efficiency of the positive electrode material.

[0032] In other embodiments, the above steps S7 to S8 may use a wet recovery process in the prior art to prepare lithium carbonate from the positive electrode material. The wet recovery process prepares lithium carbonate from the positive electrode material, which requires consumption of acid and oxidizing agent.

[0033] In this embodiment, preferably, step S7 includes: Step S71, pressing the positive electrode material into a sheet material, wherein a plurality of holes are distributed on the sheet material.

[0034] Step S72: Use the sheet material as the cathode of the electrolytic cell, use the carbon rod as the anode of the electrolytic cell, and use electrolytic reduction to leach lithium ions into the electrolyte of the electrolytic cell.

[0035] Step S8 includes: extracting an electrolyte containing lithium ions, adding a precipitant containing carbonate, and filtering to obtain a precipitate that is lithium carbonate.

[0036] The above method uses electrolytic reduction to extract lithium from the recovered positive electrode material, and then precipitates the lithium ions. The precipitate obtained after filtration is lithium carbonate, which is one of the raw materials for preparing positive electrode materials for lithium iron phosphate batteries. Compared with wet recovery, the above method does not use acid and oxidant, has less secondary pollution, and is more environmentally friendly. In addition, the above method presses the positive electrode material into a sheet material with holes (small holes), and the contact area between the sheet material and the electrolyte is larger, and the leaching efficiency of lithium ions is higher.

[0037] Second, see Figure 1~Figure 4 This embodiment provides a recycling system for waste lithium iron phosphate battery positive electrode materials, which should implement the above method, and the system includes a separation device and a pressing device. The separation device is used to separate and collect the positive electrode materials on the aluminum foil 15, and the pressing device is used to press the positive electrode materials into a sheet material with holes.

[0038] The separation device comprises a support platform 41, a first clamping mechanism 42, a second clamping mechanism 43, a material scraping mechanism and a material receiving mechanism.

[0039] The support platform 41 plays a supporting role. The support platform 41 has a longitudinal direction ( Figure 2 A first clamping station 11 and a second clamping station 12 are arranged at intervals (in the left and right direction as shown).

[0040] The first clamping mechanism 42 is disposed at the first clamping station 11 .

[0041] The second clamping mechanism 43 is disposed at the second clamping station 12 ; the first clamping mechanism 42 and the second clamping mechanism 43 are respectively used to clamp two positions of the aluminum foil 15 ; the first clamping mechanism 42 and the second clamping mechanism 43 can be synchronously moved leftward or rightward.

[0042] The scraping mechanism includes a scraper 14, which can scrape along the width direction of the support platform 41 ( Figure 2 The aluminum foil 15 is moved in the forward and backward directions (as shown) to scrape off the positive electrode material on the aluminum foil 15.

[0043] The material receiving mechanism includes a material receiving hopper 451 disposed below the support platform 41 , and the material receiving hopper 451 is used to collect positive electrode materials.

[0044] The aluminum foil 15 is clamped and limited by the clamping action of the first clamping mechanism 42 and the second clamping mechanism 43. At the same time, the first clamping mechanism 42 and the second clamping mechanism 43 can be synchronously moved left or right to realize the transportation of the aluminum foil 15. Specifically, the first clamping mechanism 42 and the second clamping mechanism 43 clamp the aluminum foil 15 and drive the aluminum foil 15 to move right, then release the aluminum foil 15, move it to the left to reset, and then re-clamp the aluminum foil 15 to drive the aluminum foil 15 to move right, so that the positive electrode material at different positions on the aluminum foil 15 can be scraped off by the scraper 14, and the scraped positive electrode material falls into the receiving hopper 451 to be collected.

[0045] The upper side of the scraper 14 is provided with two hanging blocks 441, and the hanging blocks 441 are slidably connected with guide rods 442, and the guide rods 442 are connected to the support platform 41, as shown in FIG. Figure 2 As shown, the axis of the guide rod 442 is arranged along the width direction of the support platform 41. The scraper 14 can be moved by moving the lifting block 441.

[0046] The first clamping mechanism 42 includes a first vertical plate 421 , a first supporting plate 422 , a first clamping plate 423 , a first hanging ring 424 , a first cross bar 425 and a guide plate 426 .

[0047] The first support plate 422 is fixed on the first vertical plate 421, and a first groove is opened on the support platform 41. Under the self-weight of the first vertical plate 421 and the first support plate 422, the lower side of the first support plate 422 slides in contact with the bottom of the first groove, and the upper side of the first support plate 422 can contact the lower side of the aluminum foil 15.

[0048] The first clamping plate 423 is located above the first supporting plate 422 and is longitudinally slidably connected to the first vertical plate 421 . The lower side of the first clamping plate 423 can contact the upper side of the aluminum foil 15 .

[0049] One end of the first hanging ring 424 is connected to the first clamping plate 423 , and the other end is detachably connected to the first cross bar 425 via screws.

[0050] One end of the first cross bar 425 is connected to the guide plate 426, and the other end is connected to the hanging block 441. Figure 2 As shown, the hoisting block 441 can drive the first cross bar 425 to move forward and backward, and the first cross bar 425 can move left and right and up and down relative to the hoisting block 441. Specifically, a moving block 443 is slidably connected to the inside of the hoisting block 441, and the first cross bar 425 is slidably connected to the moving block 443 up and down. A spring 444 is provided between the moving block 443 and the hoisting block 441 for moving the moving block 443 to the left.

[0051] The guide plate 426 is fixedly arranged on the support platform 41; the guide plate 426 has a guide track for guiding the first crossbar 425 to move up and down or left and right, wherein the upward movement of the first crossbar 425 is realized by extending the guide track upward; the downward movement of the first crossbar 425 is realized by extending the guide track downward; the rightward movement of the first crossbar 425 is realized by setting an outward slope in the guide track, that is, gradually reducing the depth of the guide track to give the first crossbar 425 a rightward reaction force, and the first crossbar 425 compresses the spring 444, thereby realizing the rightward movement of the first crossbar 425; the leftward movement of the first crossbar 425 is realized by setting an inward slope in the guide track, that is, gradually increasing the depth of the guide track, so that the first crossbar 425 is reset to the left under the rightward reset force of the spring 444. Maintaining the up and down position and left and right position of the first crossbar 425 is realized by extending the guide track horizontally and keeping the depth of the guide track unchanged.

[0052] The second clamping mechanism 43 includes a second vertical plate 431 , a second supporting plate 432 , a second clamping plate 433 , a second hanging ring, and a second cross bar 434 .

[0053] The second support plate 432 is fixed on the second vertical plate 431, and a second groove is opened on the support platform 41. Under the self-weight of the second vertical plate 431 and the second support plate 432, the lower side of the second support plate 432 slides in contact with the bottom of the second groove, and the upper side of the second support plate 432 can contact the lower side of the aluminum foil 15.

[0054] The second clamping plate 433 is located above the second supporting plate 432 and is longitudinally slidably connected to the second vertical plate 431 . The lower side of the second clamping plate 433 can contact the upper side of the aluminum foil 15 .

[0055] One end of the second hanging ring is connected to the second clamping plate 433 , and the other end is detachably connected to the second cross bar 434 via screws.

[0056] One end of the second crossbar 434 is connected to the first crossbar 425, and the second crossbar 434 moves with the first crossbar 425. The shape of the second crossbar 434 is set as needed.

[0057] In this embodiment, the guide rails include a rear downward pressing guide rail 51, a rear rightward moving guide rail 52, a rearward holding guide rail 53, a rear upward moving guide rail 54, a rear leftward moving guide rail 55, a front downward pressing guide rail 56, a front rightward moving guide rail 57, a front holding guide rail 58, a front upward moving guide rail 59, and a front leftward moving guide rail 61, which are connected in sequence, wherein the rear leftward moving guide rail 55 and the front downward pressing guide rail 56 are connected by an upward moving transfer rail 62, and the front leftward moving guide rail 61 and the rear downward pressing guide rail 51 are connected by a downward moving transfer rail 63.

[0058] Each area of ​​the guide track corresponds to the function and purpose of the corresponding backward path or forward path, specifically: The rear downward pressing guide rail 51 extends downward, so that the first cross bar 425 drives the first clamping plate 423 and the second clamping plate 433 to move downward along the track thereof, so that when the scraper 14 moves along the rearward first path 21, the first clamping mechanism 42 and the second clamping mechanism 43 clamp two parts of the aluminum foil 15 at the first clamping station 11 and the second clamping station 12; The depth of the rightward moving guide rail 52 gradually decreases, so that the first crossbar 425 drives the first clamping plate 423 and the second clamping plate 433 to move rightward, so that when the scraper 14 moves along the second backward path 22, the area between the two clamped parts of the aluminum foil 15 is moved rightward to the scraping station 13; The backward holding guide rail 53 extends horizontally and its depth is kept equal to the minimum depth of the backward rightward moving guide rail 52. At this time, the first crossbar 425 and the lifting block 441 move synchronously (the two do not move relative to each other), so that when the scraper 14 moves along the backward third path 23, the first clamping mechanism 42 and the second clamping mechanism 43 keep clamping the aluminum foil 15 to a limited position, so that the aluminum foil 15 is fixed at the current position, so that the positive electrode material on the aluminum foil 15 can be scraped off by the scraper 14; The rear upward guide rail 54 extends upward, so that the first cross bar 425 drives the first clamping plate 423 and the second clamping plate 433 to move upward along their tracks, so as to release the clamping of the aluminum foil 15 when the scraper 14 moves along the rear fourth path 24; The depth of the backward leftward moving guide rail 55 gradually increases, so that the first crossbar 425 moves leftward under the restoring force of the spring 444, so that when the scraper 14 moves along the backward fifth path 25, the first clamping mechanism 42 and the second clamping mechanism 43 move leftward and reset; The forward downward pressing guide rail 56 extends downward, so that the first cross bar 425 drives the first clamping plate 423 and the second clamping plate 433 to move downward along the track thereof, so that when the scraper 14 moves along the forward first path 26, the first clamping mechanism 42 and the second clamping mechanism 43 clamp the other two parts of the aluminum foil 15 at the first clamping station 11 and the second clamping station 12 respectively; The depth of the forward rightward moving guide rail 57 gradually decreases, so that the first crossbar 425 drives the first clamping plate 423 and the second clamping plate 433 to move rightward, so that when the scraper 14 moves along the forward second path 27, the area between the other two clamped parts of the aluminum foil 15 is moved rightward to the scraping station 13; The forward holding guide rail 58 extends horizontally and its depth is kept equal to the minimum depth of the forward rightward moving guide rail 57. At this time, the first crossbar 425 and the hoisting block 441 move synchronously (the two do not move relative to each other), so that when the scraper 14 moves along the forward third path 28, the first clamping mechanism 42 and the second clamping mechanism 43 keep clamping the aluminum foil 15 to a limited position, so that the aluminum foil 15 is fixed at the current position, so that the positive electrode material on the aluminum foil 15 can be scraped off by the scraper 14; The forward upward guide rail 59 extends upward, so that the first cross bar 425 drives the first clamping plate 423 and the second clamping plate 433 to move upward along their tracks, so as to release the clamping of the aluminum foil 15 when the scraper 14 moves along the forward fourth path 29; The depth of the forward leftward guide rail 61 gradually increases, so that the first crossbar 425 moves leftward under the restoring force of the spring 444, so that when the scraper 14 moves along the forward fifth path 31, the first clamping mechanism 42 and the second clamping mechanism 43 move leftward and reset.

[0059] It can be understood that the total distance that the first cross bar 425 is moved upward by the rear upward guide rail 54 and the upward transfer guide rail 62 should be equal to the total distance that the first cross bar 425 is moved downward by the downward transfer guide rail 63 and the rear downward pressure guide rail 51; this embodiment does not limit the driving method for moving the first cross bar 425 along the upward transfer guide rail 62 and the downward transfer guide rail 63.

[0060] The pressing device includes a fixed frame 67 , an air supply duct 68 and a movable enclosure 69 .

[0061] The fixing frame 67 is fixedly arranged and is roughly T-shaped. An air inlet 66 is arranged on the vertical portion of the fixing frame 67. The air inlet 66 is connected to an air supply pipe 68.

[0062] The air supply pipe 68 is connected to the air inlet 66 and is used to supply a hot air flow at an angle of 45° to 55° to the air inlet 66 .

[0063] The movable enclosure 69 is movably arranged left and right, and is slidably connected to the fixed frame 67. The movable enclosure 69 and the fixed frame 67 can define a space together to form a cavity 64, and the cavity 64 can be connected to the receiving hopper 451, so that the positive electrode material collected by the receiving hopper enters the cavity 64. An extension rod 65 is provided on one side of the movable enclosure 69, and the extension rod 65 is located in the cavity 64 and can block the air inlet 66.

[0064] After the positive electrode material collected by the receiving funnel enters the cavity 64, the hot air in the air supply pipe 68 enters the cavity 64 through the air inlet 66, so that the viscous material in the positive electrode material remains in a relatively soft state, which is conducive to compacting the positive electrode material into a sheet material, and the sheet material is not easy to loosen; the movable enclosure 69 is moved to the left, and the extension rod 65 is inserted into the air inlet 66 to block the air inlet 66. The movable enclosure 69 and the fixed frame 67 work together to compact the positive electrode material into a sheet material with holes. After the movable enclosure 69 is moved to the right and separated from the vertical part of the fixed frame 67, the sheet material can naturally fall and separate from the pressing device. In addition, before the extension rod 65 is inserted into the air inlet 66 to block the air inlet 66, the hot air in the air supply pipe 68 enters the cavity 64 through the air inlet 66, which can also prevent some dusty positive electrode materials from overflowing from the air inlet 66.

[0065] This embodiment further includes a leveling station 71 and a spray head 72 .

[0066] The leveling station 71 is disposed on the left side of the first clamping station 11 and the second clamping station 12 , and the width of the area of ​​the support platform 41 located at the leveling station 71 is slightly smaller than the width of the aluminum foil 15 .

[0067] The jet is connected to the air supply pipe 68. A plurality of jet heads 72 are evenly arranged along the width direction of the support platform 41 and disposed obliquely above the leveling station 71. The jet direction of the jet heads 72 is obliquely downward toward the leveling station 71.

[0068] Hot air is blown toward the aluminum foil 15 on the leveling station 71 through the nozzle 72, which can not only smooth the aluminum foil 15 by airflow to facilitate the subsequent separation of the positive electrode material, but also heat the positive electrode material to soften the viscous material in the positive electrode material to facilitate scraping.

[0069] Finally, it should be noted that the above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. In the absence of conflicts, the embodiments of the present application and the features in the embodiments may be arbitrarily combined with each other. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for recycling waste lithium iron phosphate battery positive electrode materials, characterized in that: include: Step S1, peeling off a positive electrode sheet from a waste lithium iron phosphate battery, wherein the positive electrode sheet comprises an aluminum foil and a positive electrode material bonded to the aluminum foil; Step S2, clamping two parts of the aluminum foil at a first clamping station and a second clamping station respectively, wherein the first clamping station and the second clamping station are spaced apart along the length direction of the aluminum foil; Step S3, moving the area between the two clamped parts of the aluminum foil to the right to the scraping station; Step S4, scraping the positive electrode material on the aluminum foil along the width direction of the aluminum foil and collecting it; Step S5, releasing the clamping of the aluminum foil; Step S6, repeating steps S2 to S5 to continuously recover the positive electrode material on the aluminum foil; Step S7, extracting lithium ions from the positive electrode material obtained in step S4; Step S8, using the lithium ions obtained in step S7 to prepare a new positive electrode material for a lithium iron phosphate battery; Among them, the scraping station is provided with a scraper, and the scraper moves along the width direction of the aluminum foil. The moving path of the scraper includes a backward path and a forward path. The scraper moves in a direction opposite to the backward path to form the forward path. The scraper moves cyclically along the backward path and the forward path.

2. The method for recycling waste lithium iron phosphate battery positive electrode materials according to claim 1, characterized in that: The backward path includes a first backward path, a second backward path, a third backward path, a fourth backward path, and a fifth backward path which are connected in sequence; The forward path includes a first forward path, a second forward path, a third forward path, a fourth forward path, and a fifth forward path which are connected in sequence; The first backward path overlaps with the fifth forward path and is in the opposite direction, the second backward path overlaps with the fourth forward path and is in the opposite direction, the third backward path overlaps with the third forward path and is in the opposite direction, the fourth backward path overlaps with the second forward path and is in the opposite direction, and the fifth backward path overlaps with the first forward path and is in the opposite direction; The lengths of the third backward path and the third forward path are greater than or equal to the width of the aluminum foil; When the scraper moves along the first backward path, the first clamping mechanism and the second clamping mechanism clamp two parts of the aluminum foil at the first clamping station and the second clamping station respectively; when the scraper moves along the second backward path, the area between the two clamped parts of the aluminum foil is moved rightward to the scraping station; when the scraper moves along the third backward path, the first clamping mechanism and the second clamping mechanism maintain the clamping limit of the aluminum foil, so that the aluminum foil is fixed at the current position, so that the positive electrode material on the aluminum foil can be scraped off by the scraper; when the scraper moves along the fourth backward path, the aluminum foil is released; when the scraper moves along the fifth backward path, the first clamping mechanism and the second clamping mechanism move leftward and reset; When the scraper moves forward along the first path, the other two parts of the aluminum foil are clamped at the first clamping station and the second clamping station by the first clamping mechanism and the second clamping mechanism respectively; when the scraper moves forward along the second path, the area between the other two clamped parts of the aluminum foil is moved right to the scraping station; when the scraper moves forward along the third path, the first clamping mechanism and the second clamping mechanism maintain the clamping limit of the aluminum foil, so that the aluminum foil is fixed in the current position, so as to facilitate the scraping of the positive electrode material on the aluminum foil by the scraper; when the scraper moves forward along the fourth path, the aluminum foil is released from the clamping; when the scraper moves forward along the fifth path, the first clamping mechanism and the second clamping mechanism move left and reset.

3. The method for recycling waste lithium iron phosphate battery positive electrode materials according to claim 1 or 2, characterized in that: Step S7 includes: Step S71: Press the positive electrode material of step S6 into a sheet material Step S72: Use the sheet material as the cathode of the electrolytic cell, use the carbon rod as the anode of the electrolytic cell, and use electrolytic reduction to leach lithium ions into the electrolyte of the electrolytic cell.

4. The method for recycling the positive electrode material of waste lithium iron phosphate batteries according to claim 3, characterized in that: A plurality of holes are distributed on the sheet material.

5. A recycling system for waste lithium iron phosphate battery positive electrode materials, using the recycling method for waste lithium iron phosphate battery positive electrode materials as described in any one of claims 1 to 4, characterized in that: include: A support platform, with the first clamping station and the second clamping station spaced apart along its length direction; A first clamping mechanism, disposed at the first clamping station; A second clamping mechanism is arranged at the second clamping station; the first clamping mechanism and the second clamping mechanism are respectively used to clamp two parts of the aluminum foil; the first clamping mechanism and the second clamping mechanism can be synchronously moved left or right; A scraping mechanism, comprising the scraper; The material receiving mechanism comprises a material receiving hopper arranged below the support platform for collecting positive electrode materials.

6. The recycling system for waste lithium iron phosphate battery positive electrode materials according to claim 5, characterized in that: Two hanging blocks are arranged on the upper side of the scraper, and the hanging blocks are slidably connected with guide rods, and the axes of the guide rods are arranged along the width direction of the support platform.

7. The recycling system for waste lithium iron phosphate battery positive electrode materials according to claim 6, characterized in that: The first clamping mechanism comprises: First vertical board; A first support plate is fixed on the first vertical plate, a first groove is formed on the support platform, a lower side of the first support plate is in sliding contact with a bottom of the first groove, and an upper side of the first support plate is in contact with a lower side of the aluminum foil; A first clamping plate, located above the first supporting plate and longitudinally slidably connected to the first vertical plate, wherein the lower side of the first clamping plate can contact the upper side of the aluminum foil; A first lifting ring, one end of which is connected to the first clamping plate and the other end of which is connected to the first crossbar; A first cross bar, one end of which is connected to the guide plate and the other end of which is connected to the lifting block; the lifting block can drive the first cross bar to move forward and backward, and the first cross bar can move left and right and up and down relative to the lifting block; The guide plate is fixedly arranged on the support platform; the guide plate is provided with a guide track for guiding the first cross bar to move up and down or left and right.

8. The recycling system for waste lithium iron phosphate battery positive electrode materials according to claim 7, characterized in that: The second clamping mechanism comprises: The second vertical board; A second support plate is fixed on the second vertical plate, a second groove is formed on the support platform, a lower side of the second support plate is in sliding contact with a bottom of the second groove, and an upper side of the second support plate is in contact with a lower side of the aluminum foil; A second clamping plate is located above the second supporting plate and is longitudinally slidably connected to the second vertical plate, and the lower side of the second clamping plate can contact the upper side of the aluminum foil; A second lifting ring, one end of which is connected to the second clamping plate and the other end of which is connected to the second cross bar; One end of the second crossbar is connected to the first crossbar; the second crossbar moves with the first crossbar.

9. The system for recycling waste lithium iron phosphate battery positive electrode materials according to any one of claims 5 to 8, characterized in that: Also includes: A fixing frame, fixedly arranged, the fixing frame is T-shaped, and an air inlet hole is arranged on the vertical portion of the fixing frame; An air supply pipe is connected to the air inlet and is used to supply a hot air flow at an angle of 45° to 55° to the air inlet; A movable enclosure is movably arranged to move left and right, and the movable enclosure is slidably connected to the fixed frame. The movable enclosure can define a space together with the fixed frame to form a cavity, and the cavity can be connected to the receiving hopper; an extension rod is provided on one side of the movable enclosure, and the extension rod is located in the cavity and can block the air inlet.

10. The recycling system for waste lithium iron phosphate battery positive electrode materials according to claim 9, characterized in that: Also includes: A flattening station is arranged on the left side of the first clamping station and the second clamping station, and the width of the area where the support platform is located at the flattening station is slightly smaller than the width of the aluminum foil; A plurality of nozzles connected to the air supply pipe are evenly arranged along the width direction of the support platform and disposed obliquely above the leveling station, and the nozzles spray obliquely downward toward the leveling station.

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