A lithium battery electrolyte recovery system and method

Abstract

The present application relates to the technical field of battery electrolyte recovery, and discloses a lithium battery electrolyte recovery system and method, the lithium battery electrolyte recovery system comprises a base and a horizontal screw centrifuge, two drive units, a sealing cover arranged on the horizontal screw centrifuge, and two support plates arranged on the base, wherein an auxiliary mechanism is arranged on the base, the auxiliary mechanism comprises a cleaning assembly, the cleaning assembly is driven to work by the drive unit, and the cleaning work of the inner wall of the sealing cover is realized.The lithium battery electrolyte recovery system and method can effectively solve the problem that in the prior art, wet black powder is easily adhered to the surface of the slagging port after high-speed movement and stress in the centrifuge, forming an adhering layer that is difficult to fall off by itself, which not only causes the effective processing space of the equipment to become smaller, increases the safety risk of thermal runaway and combustion, but also causes the adhering layer to gradually harden after long-term accumulation, resulting in difficult cleaning of the equipment, and further affecting the continuous operation efficiency of the production line.

Description

Technical Field

[0001] This invention relates to the field of battery electrolyte recycling technology, and specifically to a lithium battery electrolyte recycling system and method. Background Technology

[0002] With the rapid development of new energy vehicles and energy storage industries, the recycling and disposal of large quantities of waste lithium batteries has become a global challenge and opportunity. Lithium-ion batteries are mainly composed of positive electrode, negative electrode, separator, electrolyte and shell. Among them, electrolyte, as the "blood" of the battery, is the carrier for the migration of lithium ions between the positive and negative electrodes.

[0003] In the existing mainstream recycling technologies, the first step is to use the powerful centrifugal force generated by high-speed rotation in a horizontal screw centrifuge to initially separate most of the liquid electrolyte from the solid black powder (a mixture of positive and negative electrode active materials) in the broken battery slurry. Then, the wet black powder separated by centrifugation is sent to a press, where most of the electrolyte adsorbed inside and remaining in the pores is further squeezed out by mechanical extrusion.

[0004] The centrifugation of electrolyte is usually carried out in a closed space filled with inert gas. The horizontal screw centrifuge continuously throws the separated wet black powder out of the slag discharge port through the screw feeder. However, even after centrifugation, the black powder still contains a small amount of electrolyte and is in a semi-dry and semi-wet viscous state. After high-speed movement and stress inside the centrifuge, this wet black powder is very easy to adhere to the surface of the slag discharge port, forming an adhesive layer that is difficult to remove on its own.

[0005] Thus, the gradual accumulation of the adhesive layer not only reduces the effective processing space of the equipment, increasing the safety risks of thermal runaway and combustion, but also gradually hardens over time, making it difficult to shut down the equipment for cleaning, thereby affecting the continuous operation efficiency of the production line. Summary of the Invention

[0006] To address the aforementioned shortcomings of existing technologies, this invention provides a lithium battery electrolyte recovery system and method. This system effectively solves the problem that, in existing technologies, wet black powder, after high-speed movement and stress inside a centrifuge, easily adheres to the surface of the slag discharge port, forming a layer that is difficult to detach on its own. This not only reduces the effective processing space of the equipment, increasing the safety risks of thermal runaway and combustion, but also causes the adhesive layer to gradually harden over time, making it difficult to clean the equipment during shutdown, thus affecting the continuous operation efficiency of the production line.

[0007] To achieve the above objectives, the present invention provides the following technical solution:

[0008] This invention provides a lithium battery electrolyte recovery system, comprising:

[0009] The base is equipped with a horizontal screw centrifuge for separating the electrolyte from the black powder.

[0010] There are two drive units, located on the front and rear sides of the horizontal screw centrifuge, respectively.

[0011] A sealing cover is installed on the horizontal screw centrifuge. The sealing cover is rotatably mounted on the base and serves to block the ejected black powder.

[0012] Two support plates are installed on the base near the black powder discharge port. The two support plates are symmetrically arranged according to the discharge position, and a storage box is installed below the two support plates.

[0013] An auxiliary mechanism is provided on the base and located at the position of the front drive unit. The auxiliary mechanism includes a cleaning component. The front drive unit drives the cleaning component to work and achieves the cleaning of black powder on the inner wall of the sealing cover.

[0014] Furthermore, the rear drive unit is connected to the horizontal screw centrifuge for transmission and realizes the separation of electrolyte and black powder, while the front drive unit is connected to the cleaning component for transmission.

[0015] Furthermore, the auxiliary mechanism includes a mounting box disposed on the base, and a cleaning component disposed inside the mounting box. The cleaning component includes a forward and reverse rotation component that is connected to the front drive unit.

[0016] Furthermore, the forward and reverse rotation assembly includes a driving bevel gear that is connected to the front drive unit. Two driven bevel gears are meshed on the outer wall of the driving bevel gear. Both driven bevel gears are provided with a drive rod. The drive rod on the front driven bevel gear rotates through the drive rod on the rear side, and a support plate and a mounting plate are respectively provided on the outer wall of the front and rear drive rods.

[0017] Furthermore, the front support plate is rotatably connected to the base, while the rear support plate is fixedly connected to the base.

[0018] Furthermore, the cleaning component includes a linkage plate fixedly mounted on the support tray, the other end of which is fixedly connected to a front support plate. Several scrapers are arranged circumferentially on the side of the front support plate away from the support tray. The mounting plate is located between the two support plates and has a mating part on it.

[0019] Furthermore, several scrapers are always in contact with the inner wall of the sealing cover, and several serrated grooves are also provided on the outer wall of the scraper on the side located in its rotation direction.

[0020] Furthermore, the mating component includes a circular seat that is fixedly connected to the mounting plate. The outer circumference of the circular seat is provided with several crushing rollers for breaking up the agglomerated black powder. The other end of the crushing rollers is connected to the rear support plate.

[0021] A method for recycling lithium battery electrolyte includes the following steps:

[0022] S1: Pre-treatment. First, a batch of waste lithium batteries is completely discharged. After removing non-core components, the cells are sent into a crusher to make them into a blocky mixture.

[0023] S2: First stage of dehydration. First, the sealing cover is closed, making the decanter centrifuge a sealed space. Then, the drive unit drives the decanter centrifuge to work and fills the sealed space with nitrogen to exhaust the air and form an inert gas protective environment. Next, the mixture is pumped into the decanter centrifuge. Through the powerful centrifugal force of the decanter centrifuge, the electrolyte and wet black powder are separated. During this process, the electrolyte flows out from the overflow port, while the wet black powder is discharged from the slag discharge port on the decanter centrifuge.

[0024] S3: Cleaning work at the slag discharge point. During the continuous discharge of wet black powder, the corresponding drive unit drives the cleaning components to work. During this process, several scrapers set on the support plate continuously scrape the inner wall of the slag discharge point to prevent wet black powder from accumulating at the slag discharge point for a long time.

[0025] S4: Secondary dehydration. The horizontal screw centrifuge feeds the wet black powder into the subsequent extrusion equipment. The extrusion equipment is started, and the pressure on the wet black powder gradually increases. The electrolyte in the pores is forcefully squeezed out. Finally, the squeezed electrolyte is sent into the collection tank.

[0026] S5: Refining and processing. The extruded black powder cake is sent into a vacuum rotary kiln or dryer, where the last trace amount of electrolyte is evaporated into steam. The steam is then extracted and sent into a condensation system. Finally, it is condensed into liquid and collected into an electrolyte collection tank.

[0027] S6: Repeat S1~S5 to recycle the electrolyte in the next batch of lithium batteries.

[0028] The technical solution provided by this invention has the following advantages compared with the prior art:

[0029] In the operation of the horizontal screw centrifuge, when wet black powder is continuously ejected from the discharge port, the front drive unit starts, driving the active bevel gear to rotate. The active bevel gear meshes with the symmetrical driven bevel gears on both sides, causing them to rotate in opposite directions. The driven bevel gears drive the support tray and the linkage disc, which in turn drive several scrapers to rotate synchronously. These scrapers are always in close contact with the inner wall of the sealing cover and the base, continuously scraping the surface. The serrated grooves on the scrapers can effectively break the stickiness of the wet black powder by "wire cutting" and "point pushing" and easily cut through the formed adhesive layer, preventing it from hardening and accumulating. This active and continuous scraping and cleaning method solves the problem of wet black powder adhering to the inner wall due to the presence of adhesive. By removing the adhesive in real time, it effectively avoids problems such as reduced effective processing space, increased risk of thermal runaway, and difficulty in shutdown and cleaning caused by the accumulation of adhesive layers. This ensures that the equipment can operate continuously for a long time, safely, and efficiently, providing a solid guarantee for the stability of the entire recycling production line. Attached Figure Description

[0030] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are merely some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without any creative effort.

[0031] Figure 1 This is a flowchart of the recycling method of the lithium battery electrolyte recycling system according to an embodiment of the present invention;

[0032] Figure 2 This is a three-dimensional structural diagram of an embodiment of the present invention;

[0033] Figure 3 This is a schematic diagram of the three-dimensional separation of the sealing cap and the horizontal screw centrifuge according to an embodiment of the present invention;

[0034] Figure 4 This is an embodiment of the present invention. Figure 3 A magnified structural diagram of part A in the middle;

[0035] Figure 5 This is an embodiment of the present invention. Figure 3 A magnified structural diagram of section B in the middle;

[0036] Figure 6 This is a three-dimensional structural diagram of the cleaning component according to an embodiment of the present invention;

[0037] Figure 7 This is a schematic diagram of the three-dimensional separation of the forward and reverse rotation component and the mounting box in an embodiment of the present invention;

[0038] Figure 8This is a schematic diagram of the three-dimensional separation of the mating component and the forward / reverse component in an embodiment of the present invention.

[0039] The numbers in the diagram represent: 100, storage bin; 200, slag discharge port; 300, overflow port;

[0040] 1. Base; 11. Horizontal screw centrifuge; 12. Support plate; 2. Drive unit; 3. Sealing cover; 4. Auxiliary mechanism; 41. Cleaning component; 411. Forward and reverse rotation component; 4111. Driving bevel gear; 4112. Driven bevel gear; 4113. Drive rod; 4114. Support plate; 4115. Mounting plate; 412. Linkage plate; 413. Scraper; 4131. Serrated groove; 414. Mating part; 4141. Circular seat; 4142. Crushing roller; 42. Mounting box. Detailed Implementation

[0041] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0042] The present invention will be further described below with reference to embodiments.

[0043] Example:

[0044] Please see Figure 1 - Figure 8 This invention provides a technical solution: a lithium battery electrolyte recovery system, comprising:

[0045] Base 1, on which a horizontal screw centrifuge 11 for separating electrolyte and black powder is installed;

[0046] There are two drive units 2, located on the front and rear sides of the horizontal screw centrifuge 11 respectively;

[0047] The sealing cover 3 is installed on the horizontal screw centrifuge 11. The sealing cover 3 is rotatably mounted on the base 1 and performs the function of blocking the black powder that is thrown out.

[0048] Among them, two support plates 12 are provided on the base 1 near the black powder discharge port 200. The two support plates 12 are symmetrically arranged according to the discharge position, and a storage box 100 is provided below the two support plates 12.

[0049] An auxiliary mechanism 4 is provided on the base 1 and located at the position of the front drive unit 2. The auxiliary mechanism 4 includes a cleaning component 41. The front drive unit 2 drives the cleaning component 41 to work and achieve the cleaning of black powder on the inner wall of the sealing cover 3.

[0050] The rear drive unit 2 is connected to the horizontal screw centrifuge 11 and performs the separation of electrolyte and black powder, while the front drive unit 2 is connected to the cleaning component 41.

[0051] The auxiliary mechanism 4 includes a mounting box 42 disposed on the base 1, and a cleaning component 41 disposed inside the mounting box 42. The cleaning component 41 includes a forward and reverse rotation component 411 that is connected to the front drive unit 2.

[0052] The forward and reverse rotation assembly 411 includes a drive bevel gear 4111 that is connected to the front drive unit 2. Two driven bevel gears 4112 are meshed on the outer wall of the drive bevel gear 4111. Each of the two driven bevel gears 4112 is provided with a drive rod 4113. The drive rod 4113 on the front driven bevel gear 4112 rotates through the drive rod 4113 on the rear driven bevel gear 4112. A support plate 4114 and a mounting plate 4115 are respectively provided on the outer wall of the front and rear drive rods 4113.

[0053] The front support plate 12 is rotatably connected to the base 1, and the rear support plate 12 is fixedly connected to the base 1.

[0054] The cleaning component 41 includes a linkage disc 412 fixedly mounted on the support tray 4114. The other end of the linkage disc 412 is fixedly connected to the front support plate 12. Several scrapers 413 are arranged in the circumferential direction on the side of the front support plate 12 away from the support tray 4114. The mounting plate 4115 is located between the two support plates 12, and a mating part 414 is provided on the mounting plate 4115.

[0055] Several scrapers 413 are always in contact with the inner wall of the sealing cover 3, and several serrated grooves 4131 are also provided on the outer wall of the scraper 413 and on the side of its rotation direction.

[0056] The mating component 414 includes a circular seat 4141 fixedly connected to the mounting plate 4115. The outer circumference of the circular seat 4141 is provided with a plurality of crushing rollers 4142 for breaking up agglomerated black powder. The other end of the plurality of crushing rollers 4142 is connected to the rear support plate 12.

[0057] In specific work,

[0058] The horizontal screw centrifuge 11 continuously ejects the separated wet black powder from the slag discharge port 200 through the screw feeder. However, even after centrifugal separation, the black powder still contains a small amount of electrolyte and is in a semi-dry and semi-wet viscous state. After high-speed movement and stress inside the centrifuge, this wet black powder is very easy to adhere to the surface of the slag discharge port 200, forming an adhesive layer that is difficult to detach on its own.

[0059] Thus, the gradual accumulation of the adhesive layer not only reduces the effective processing space of the equipment, increasing the safety risks of thermal runaway and combustion, but also gradually hardens after long-term accumulation, making it difficult to clean the equipment during shutdown, thereby affecting the continuous operation efficiency of the production line. Based on this, an auxiliary mechanism 4 is set on the base 1 of the lithium battery electrolyte recovery system. In actual operation, when wet black powder is thrown out from the slag discharge port 200 of the horizontal screw centrifuge 11, the auxiliary mechanism 4 is driven by the corresponding drive unit 2 to clean the slag discharge point, avoiding the problem of wet black powder adhering to the slag discharge point mentioned above.

[0060] Specifically, the two support plates 12 on the base 1 are symmetrically arranged according to the position of the slag discharge port 200. In the initial state, when the upper sealing cover 3 falls and seals the horizontal screw centrifuge 11 into a space, the space enclosed by the two support plates 12 is connected downward to the storage box 100 of the extrusion equipment. (It should be noted that before the sealing of the horizontal screw centrifuge 11 is completed and the electrolyte dry-wet separation is carried out, nitrogen is injected into it first. The electrolyte dry-wet separation can only be carried out after the air in the horizontal screw centrifuge 11 and the storage box 100 is exhausted.)

[0061] After inert gas is formed inside the horizontal screw centrifuge 11 and the storage tank 100, the horizontal screw centrifuge 11 is driven by the rear drive unit 2 to work. During the operation of the horizontal screw centrifuge 11, the mixture is pumped into its interior and the electrolyte and black powder are initially separated. (The horizontal screw centrifuge 11 consists of a drum, a screw feeder, a differential, a feed pipe, an overflow port 300, and a slag discharge port 200. The screw feeder is hollow inside, and the feed pipe is located inside the screw feeder. During the operation, the mixture is pumped into the centrifuge from the feed pipe. As the centrifuge works, the mixture is separated according to density difference under the action of centrifugal force. The electrolyte flows out from the overflow port 300 and is collected in the external collection tank, while the black powder is thrown against the inner wall of the drum and is gradually discharged from the slag discharge port 200 by the screw feeder. The above is the prior art and will not be described in detail here.)

[0062] Since the mixture mainly consists of black powder (positive and negative electrode active materials), electrolyte, and binder, the wet black powder that has completed the initial separation process is blocked by the base 1 and the inner wall of the sealing cover 3 when it is discharged from the slag discharge port 200. This causes the wet black powder to adhere to the inner walls of the base 1 and the sealing cover 3. Thus, the forward and reverse rotation assembly 411 driven by the front drive unit 2 operates. During this process, the linkage disc 412 and several scrapers 413 are driven to rotate synchronously through the support tray 4114, achieving the scraping and cleaning of the inner walls of the base 1 and the sealing cover 3 (specifically, two...). Each driven bevel gear 4112 is symmetrically arranged according to the driving bevel gear 4111. When the front drive unit 2 drives the driving bevel gear 4111 to rotate, the driven bevel gears 4112 on both sides rotate in opposite directions. When the two driven bevel gears 4112 are rotating, the bearing tray 4114 synchronously drives the linkage disc 412 to rotate. At this time, since several scrapers 413 are always in close contact with the inner wall of the sealing cover 3 and the inner wall of the base 1, the scrapers 413 continuously scrape the inner wall during rotation, avoiding the problem of wet black powder adhering for a long time, causing the space to become smaller and difficult to clean.

[0063] It should be noted that, as mentioned above, the binder contained in the black powder is the main problem of adhesion. Each scraper is provided with several serrated grooves 4131. By changing the contact method to "wire cutting" and "point pushing", the overall stickiness of the wet black powder can be effectively destroyed, making it easier to flow. Furthermore, the front end of the serrated grooves 4131 can easily cut through the adhesive layer, thereby destroying its bond with the inner wall and effectively preventing the accumulation of the adhesive layer. At the same time, the scraper 413 with serrated grooves can also break and loosen the wet black powder during the movement (because the black powder contains binder, it will not only adhere to the inner wall, but also adhere to the black powder itself), breaking large pieces of black powder into smaller pieces, making its structure more loose, which is convenient for subsequent extrusion of the wet black powder.

[0064] The scraper 413 scrapes the inner wall of the equipment by rotating, effectively preventing the formation of hard lumps due to long-term adhesion of wet black powder. However, the separation process between the electrolyte and the black powder is continuous, and the equipment will continuously throw out new wet black powder from the slag discharge port 200. Usually, the storage box 100 for collecting these materials is set below the equipment base 1, and the wet black powder scraped off by the scraper needs to fall naturally by gravity.

[0065] Under this condition, when the scraper 413 scrapes off the relatively "old" wet black powder that has adhered to the inner wall, these materials will collide and mix with the fresh wet black powder continuously thrown out from the slag discharge port 200 in the air or at the entrance of the storage box 100 during the falling process. Since the wet black powder itself is sticky, this mixing of new and old materials is very likely to cause secondary adhesion, forming larger and more irregular agglomerates. This will reduce the efficiency and uniformity of subsequent extrusion and dehydration. Based on this, the lithium battery electrolyte recovery system is equipped with a mating component 414. The black powder on the inner wall and the newly thrown black powder will be impacted by the mating component 414, thereby avoiding secondary adhesion and laying the foundation for the uniform extrusion of the wet black powder in the future.

[0066] Specifically, as mentioned above, the two driven bevel gears 4112 rotate in opposite directions. Therefore, the circular seat 4141 and several crushing rollers 4142 rotate in opposite directions to the scraper 413. When the driving bevel gear 4111 is rotating, several crushing rollers 4142 and scraper 413 rotate in opposite directions (the crushing rollers 4142 are positioned closer to the discharge port than the scraper 413). Thus, when the wet black material falling naturally from above is falling, it will be further impacted by several crushing rollers 4142. This not only further reduces the volume of wet black powder, but also the rotating crushing rollers 4142 can effectively prevent the "old" black powder and the "new" black powder from sticking together again.

[0067] It should be noted that during the rotation of the crushing rollers 4142, some wet black powder that is thrown out of the slag discharge port 200 will preferentially contact the crushing rollers 4142. The crushing rollers 4142 will counteract the outward force of the wet black powder. After the two forces are counteracted, some of the wet black powder will fall directly into the storage box 100 below, which indirectly reduces the working intensity of the scrapers 413.

[0068] It is worth emphasizing that the micro-concave coating head glue tank based on the quick-load and unload structure has the following main advantages:

[0069] Advantage 1: During the operation of the horizontal screw centrifuge 11, when wet black powder is continuously ejected from the discharge port 200, the front drive unit 2 starts, driving the active bevel gear 4111 to rotate. The active bevel gear 4111 meshes with the symmetrical driven bevel gears 4112 on both sides, causing them to rotate in opposite directions. The driven bevel gears 4112 drive the support tray 4114 and the linkage disc 412, which in turn drives several scrapers 413 to rotate synchronously. These scrapers 413 are always in close contact with the inner wall of the sealing cover 3 and the base 1, continuously scraping the surface. The serrated grooves 41 on the scrapers 413... 31. It can effectively break the stickiness of wet black powder by "wire cutting" and "point pushing" and easily cut through the formed adhesive layer, preventing it from hardening and accumulating. This active and continuous scraping and cleaning method solves the problem of wet black powder sticking to the inner wall due to the presence of adhesive. By removing the adhesive in real time, it effectively avoids problems such as reduced effective processing space, increased risk of thermal runaway, and difficulty in cleaning downtime caused by the accumulation of adhesive layer. This ensures that the equipment can operate continuously for a long time, safely and efficiently, providing a solid guarantee for the stability of the entire recycling production line.

[0070] Secondly, this embodiment employs a reverse-rotating crushing mechanism, driven by the same drive unit 2 as the scraper 413. However, through bevel gear reversal, the rotation directions of several crushing rollers 4142 on the circular seat 4141 are completely opposite to those of the scraper 413. When the scraper 413 scrapes off the "old" wet black powder from the inner wall, this material falls together with the "new" wet black powder thrown out from the slag discharge port 200. During the fall, they immediately come into contact with the reverse-rotating crushing rollers 4142. The impact of the crushing rollers 4142 not only further breaks up the wet black powder clumps, but more importantly, its opposite direction of motion effectively disperses the old and new materials, preventing them from sticking together again into larger agglomerates due to stickiness. This reverse differential crushing design solves the problem of secondary adhesion during the material's fall, ensuring that the wet black powder falling into the lower storage box 100 is in a loose state with a loose structure and uniform particle size. This creates extremely favorable conditions for the subsequent extrusion and dehydration process, greatly improving the efficiency and uniformity of extrusion and dehydration.

[0071] Thirdly, the entire auxiliary mechanism 4 is a collaborative system. First, the rotating scraper 413 peels off the hardened or semi-hardened adhesive layer on the inner wall of the equipment and performs preliminary crushing and loosening of large pieces of material through its serrated groove 4131. Then, in the falling channel, the counter-rotating crushing roller 4142 performs high-frequency impact and further crushing on the viscous material newly thrown out from the slag discharge port 200 and the material that has just been scraped off. This provides continuous and multi-stage fine processing of wet black powder. The synergistic effect of scraping and crushing maximizes the processing effect of wet black powder, not only keeping the inside of the equipment clean, but also directly optimizing the physical form of the output material.

[0072] Fourthly, each scraper has several serrated grooves 4131. By changing the contact method to "wire cutting" and "point pushing", the overall stickiness of the wet black powder can be effectively destroyed, making it easier to flow. The front end of the serrated grooves 4131 can easily cut through the adhesive layer, thereby destroying its bond with the inner wall and effectively preventing the accumulation of the adhesive layer. At the same time, the scraper 413 with serrated grooves can also break and loosen the wet black powder during the movement (because the black powder contains binder, it will not only stick to the inner wall, but also stick to the black powder itself), breaking large pieces of black powder into smaller pieces, making its structure more loose, which is convenient for subsequent extrusion of the wet black powder.

[0073] Fifthly, the crushing rollers 4142 are positioned closer to the slag discharge port 200 than the scraper 413. When wet black powder is thrown out at high speed, it will preferentially contact the crushing rollers 4142. The rotation of the crushing rollers 4142 can offset part of the initial kinetic energy of the wet black powder, reducing its speed and causing it to fall directly. During this process, not all the newly thrown material will impact the scraper 413 or the inner wall of the equipment at full speed. Instead, a considerable portion will be directly "intercepted" by the crushing rollers 4142 and guided to fall. Through the early interception and diversion by the crushing rollers 4142, the workload of the subsequent scraper 413 is effectively reduced, the service life of key vulnerable parts such as the scraper 413 is extended, and the maintenance frequency and cost are reduced.

[0074] Please see Figure 1 Another aspect of the present invention provides a method for recycling lithium battery electrolyte, comprising the following steps:

[0075] S1: Pre-treatment. First, a batch of waste lithium batteries is completely discharged. After removing non-core components, the cells are sent into a crusher to make them into a blocky mixture.

[0076] S2: First stage of dehydration. First, the sealing cover 3 is closed, making the horizontal screw centrifuge 11 a sealed space. Then, the drive unit 2 drives the horizontal screw centrifuge 11 to work and fills its sealed space with nitrogen gas, exhausting the air and forming an inert gas protective environment. Next, the mixture is pumped into the horizontal screw centrifuge 11. Through the strong centrifugal force of the horizontal screw centrifuge 11, the electrolyte and wet black powder are separated. During this process, the electrolyte flows out from the overflow port 300, while the wet black powder is discharged from the slag discharge port 200 on the horizontal screw centrifuge 11.

[0077] S3: Cleaning work at the slag discharge point. During the continuous discharge of wet black powder, the corresponding drive unit 2 drives the cleaning component 41 to work. During this process, several scrapers 413 set on the support plate 12 continuously scrape the inner wall of the slag discharge point to prevent wet black powder from accumulating at the slag discharge point for a long time.

[0078] S4: Secondary dehydration. The horizontal screw centrifuge 11 feeds the wet black powder into the subsequent extrusion equipment. The extrusion equipment is started, and the pressure on the wet black powder gradually increases. The electrolyte in the pores is forcefully squeezed out. Finally, the squeezed electrolyte is sent into the collection tank.

[0079] S5: Refining and processing. The extruded black powder cake is sent into a vacuum rotary kiln or dryer, where the last trace amount of electrolyte is evaporated into steam. The steam is then extracted and sent into a condensation system. Finally, it is condensed into liquid and collected into an electrolyte collection tank.

[0080] S6: Repeat S1~S5 to recycle the electrolyte in the next batch of lithium batteries.

[0081] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions will not cause the essence of the corresponding technical solutions to deviate from the protection scope of the technical solutions of the embodiments of the present invention.

Claims

1. A lithium battery electrolyte recovery system, characterized in that, include: Base (1), on which a horizontal screw centrifuge (11) for separating electrolyte and black powder is provided; Two drive units (2) are provided and are located on the front and rear sides of the horizontal screw centrifuge (11), respectively. A sealing cover (3) is set on the horizontal screw centrifuge (11). The sealing cover (3) is rotatably set on the base (1) and performs the function of blocking the black powder thrown out. Two support plates (12) are provided on the base (1) near the black powder discharge port (200). The two support plates (12) are symmetrically arranged according to the discharge position, and a storage box (100) is provided below the two support plates (12). An auxiliary mechanism (4) is provided on the base (1) and at the position of the front drive unit (2). The auxiliary mechanism (4) includes a cleaning component (41). The front drive unit (2) drives the cleaning component (41) to work and achieves the cleaning of black powder on the inner wall of the sealing cover (3). The auxiliary mechanism (4) includes a mounting box (42) disposed on the base (1), and a cleaning component (41) disposed inside the mounting box (42). The cleaning component (41) includes a forward and reverse rotation component (411) that is connected to the front drive unit (2). The forward and reverse rotation assembly (411) includes a drive bevel gear (4111) that is connected to the front drive unit (2). The outer wall of the drive bevel gear (4111) is meshed with two driven bevel gears (4112). Each of the two driven bevel gears (4112) is provided with a drive rod (4113). The drive rod (4113) on the front driven bevel gear (4112) rotates through the drive rod (4113) on the rear side. The outer walls of the front and rear drive rods (4113) are respectively provided with a support plate (4114) and a mounting plate (4115). The cleaning component (41) includes a linkage disc (412) fixedly mounted on a support tray (4114). The other end of the linkage disc (412) is fixedly connected to a front support plate (12). Several scrapers (413) are arranged in the circumferential direction on the side of the front support plate (12) away from the support tray (4114). The mounting disc (4115) is located between two support plates (12), and a mating part (414) is provided on the mounting disc (4115). Several scrapers (413) are always in contact with the inner wall of the sealing cover (3), and several sawtooth grooves (4131) are also provided on the outer wall of the scraper (413) and on the side of its rotation direction.

2. The lithium battery electrolyte recovery system according to claim 1, characterized in that: The rear drive unit (2) is connected to the horizontal screw centrifuge (11) and performs the separation of electrolyte and black powder. The front drive unit (2) is connected to the cleaning component (41).

3. The lithium battery electrolyte recovery system according to claim 1, characterized in that: The front support plate (12) is rotatably connected to the base (1), and the rear support plate (12) is fixedly connected to the base (1).

4. The lithium battery electrolyte recovery system according to claim 1, characterized in that: The mating component (414) includes a circular seat (4141) fixedly connected to the mounting plate (4115). The outer circumference of the circular seat (4141) is provided with a plurality of crushing rollers (4142) for crushing agglomerated black powder. The other end of the plurality of crushing rollers (4142) is connected to the rear support plate (12).

5. The recycling method of a lithium battery electrolyte recycling system according to claim 1, characterized in that, Includes the following steps: S1: Pre-treatment. First, a batch of waste lithium batteries is completely discharged. After removing non-core components, the cells are sent into a crusher to make them into a blocky mixture. S2: First stage of dehydration. First, close the sealing cover (3) to make the horizontal screw centrifuge (11) a closed space. Then, the drive unit (2) drives the horizontal screw centrifuge (11) to work and fills the closed space with nitrogen gas to exhaust the air and form an inert gas protective environment. Next, pump the mixture into the horizontal screw centrifuge (11). Through the strong centrifugal force of the horizontal screw centrifuge (11), the electrolyte and wet black powder are separated. During this process, the electrolyte flows out from the overflow port (300), while the wet black powder is discharged from the slag discharge port (200) on the horizontal screw centrifuge (11). S3: Cleaning work at the slag discharge point. During the continuous discharge of wet black powder, the corresponding drive unit (2) drives the cleaning component (41) to work. During this process, several scrapers (413) set on the support plate (12) continuously scrape the inner wall of the slag discharge point to prevent wet black powder from accumulating at the slag discharge point for a long time. S4: Secondary dehydration, horizontal screw centrifuge (11) sends wet black powder into subsequent extrusion equipment, starts extrusion equipment, the pressure on wet black powder gradually increases, the electrolyte in the pores is forcefully squeezed out, and finally, the squeezed electrolyte is sent into the collection tank. S5: Refining and processing. The extruded black powder cake is sent into a vacuum rotary kiln or dryer, where the last trace amount of electrolyte is evaporated into steam. The steam is then extracted and sent into a condensation system. Finally, it is condensed into liquid and collected into an electrolyte collection tank. S6: Repeat S1~S5 to recycle the electrolyte in the next batch of lithium batteries.

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