A lithium iron phosphate anode recycling device

Abstract

This utility model discloses a lithium iron phosphate anode sheet recycling device, comprising: a stirring tank; inside the tank, from top to bottom, are a filter mechanism for filtering copper foil, a first stirrer, and a second stirrer; the bottom of the stirring tank is connected to a liquid outlet pipe, which is connected to the feed end of a centrifugal separator, the centrifugal separator being used to separate graphite. This utility model allows for continuous production, achieving the separation of copper foil and graphite in the anode sheet, and improving recycling efficiency.

Description

Technical Field

[0001] This utility model relates to the field of lithium battery recycling technology, and in particular to a lithium iron phosphate negative electrode recycling device. Background Technology

[0002] The harmless treatment of spent lithium-ion batteries is an urgent development direction globally. Generally, the electrolyte in the negative electrode sheet is first pyrolyzed to separate or remove the electrolyte, resulting in high impurity and copper content in the negative electrode. Alternatively, mechanical crushing can be used to separate the negative electrode sheet, but this results in high levels of metallic foreign matter, high impurity content, and a large amount of dust. However, the quality of the crushed graphite and copper foil materials is poor, requiring acid washing and purification of the graphite, and resulting in significant copper foil loss.

[0003] Chinese patent CN 221544715U discloses a carbon-copper separation device for battery negative electrode. This device can separate graphite and copper foil, but it consumes a large amount of water and cannot be used for continuous production. Utility Model Content

[0004] To address the shortcomings of existing technologies, the purpose of this invention is to provide a lithium iron phosphate anode recycling device that achieves continuous production by recycling the water after graphite separation.

[0005] To achieve the above objectives, the technical solution of this utility model is as follows:

[0006] A lithium iron phosphate anode recycling device includes: a stirring tank, inside which a filter mechanism for filtering copper foil, a first stirrer, and a second stirrer are arranged from top to bottom; the bottom of the stirring tank is connected to a liquid outlet pipe, which is connected to the feed end of a centrifugal separator, the centrifugal separator being used to separate graphite.

[0007] Preferably, the first agitator includes a first motor, a first agitator shaft, and agitator blades.

[0008] Preferably, the filtration mechanism is disposed above the stirring blades and includes a filter screen; the filter screen is fixedly connected to the lifting mechanism.

[0009] Preferably, the second stirrer includes a second motor, a second stirring shaft, and stirring blades.

[0010] Preferably, the number of the second stirrers is at least two.

[0011] Preferably, the centrifugal separator is equipped with a filtration and sedimentation mechanism at the outlet below, which is connected to the mixing tank through a water circulation pipe.

[0012] Preferably, the centrifuge is equipped with a feeding screw mechanism, which performs solid-liquid separation of the graphite-containing ink in the centrifuge under the action of the third agitator.

[0013] Preferably, the discharge end of the centrifugal separator is also connected to a hopper for receiving the separated graphite.

[0014] Compared with the prior art, this utility model has the following advantages:

[0015] This invention provides a lithium iron phosphate anode sheet recycling device, which separates copper foil and graphite through water immersion and stirring, and then recovers the graphite by centrifugation, enabling continuous production. Wastewater from graphite recovery is returned to the stirring tank via a circulation pipeline, achieving water resource recycling. Attached Figure Description

[0016] The features and advantages of this utility model will be more clearly understood by referring to the accompanying drawings. The drawings are schematic and should not be construed as limiting the utility model in any way. In the drawings:

[0017] Figure 1 This is a schematic diagram of the structure of a lithium iron phosphate negative electrode recycling device disclosed in a preferred embodiment of the present invention;

[0018] Explanation of reference numerals in the attached figures:

[0019] 1. Mixing tank; 2. First agitator; 21. Agitator blades; 22. First motor; 23. First agitator shaft; 3. Second agitator; 31. Agitator blades; 32. Second motor; 33. Second agitator shaft; 4. Filtration mechanism; 41. Filter screen; 5. Lifting mechanism; 6. Recovery tank; 7. Liquid outlet pipe; 8. Centrifugal separator; 9. Third agitator; 10. Feeding screw mechanism; 11. Hopper; 12. Water circulation pipe; 13. Filtration and sedimentation mechanism. Detailed Implementation

[0020] To make the above-mentioned objectives, features, and advantages of this utility model more apparent and understandable, the specific embodiments of this utility model are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a full understanding of this utility model. However, this utility model can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this utility model. Therefore, this utility model is not limited to the specific embodiments disclosed below.

[0021] In the description of this application, it should be understood that the terms "center", "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", "axial", "radial", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0022] Furthermore, the terms “first,” “second,” and “third” are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated.

[0023] A lithium iron phosphate anode recycling device, such as Figure 1 As shown, it includes: a stirring tank 1, inside which, from top to bottom, are a filter mechanism 4 for filtering copper foil, a first stirrer 2, and a second stirrer 3; the bottom of the stirring tank 1 is connected to a liquid outlet pipe 7, which connects to the feed end of a centrifugal separator 8, which is used to separate graphite. In this invention, the centrifugal separator 8 can be a horizontal spiral centrifugal separator. Under the action of the first stirrer 2 and the second stirrer 3, the negative electrode sheet, copper foil on the filter mechanism 4, and graphite and water form a slurry that enters the centrifugal separator 8 for separation, thereby achieving continuous production.

[0024] In some specific implementations, such as Figure 1 As shown, the first stirrer 2 includes a first motor 22, a first stirring shaft 23, and stirring blades 21. The first motor 22 drives the stirring blades 21 to rotate through the first stirring shaft 23. The rotational speed of the stirring blades 21 is 2-8 rpm, which drives the water flow to separate the graphite from the copper foil.

[0025] In some specific implementations, such as Figure 1 As shown, the filtration mechanism 4 is positioned above the stirring blade 21 and includes a filter screen 41; the filter screen 41 is fixedly connected to the lifting mechanism 5. The lifting mechanism 5 can lift the filter screen 41 to the top of the stirring tank 1, thereby separating the copper foil.

[0026] In some specific examples, filter 41 is 30-60 mesh.

[0027] In some specific implementations, such as Figure 1 As shown, the second stirrer 3 is located in the lower part of the inner cavity of the stirring tank 1. The second stirrer 3 also includes a second motor 32, a second stirring shaft 33, and a stirring blade 31. The second motor 32 drives the stirring blade 31 to rotate through the second stirring shaft 33. The stirring blade 31 has a high linear speed, reaching 13-30 rpm, which drives the water flow to separate the graphite from the copper foil. It can also mix the graphite and water into a slurry, thus preventing the liquid outlet pipe 7 from being blocked.

[0028] In some specific implementations, such as Figure 1 As shown, there are at least two second agitators 3 to improve the efficiency of graphite and water forming a slurry and to ensure that the graphite does not sink to the bottom and cause blockage.

[0029] In some specific implementations, such as Figure 1As shown, a filtration and sedimentation mechanism 13 is installed at the outlet below the centrifuge 8. This mechanism is connected to the top of the mixing tank 1 via a water circulation pipe 12. The water generated in the centrifuge 8 is filtered, precipitated, and then transferred to the mixing tank 1 for recycling. This design achieves water recycling and reduces water consumption.

[0030] In some specific implementations, such as Figure 1 As shown, the centrifuge 8 is equipped with a feeding screw mechanism 10, which performs solid-liquid separation on the graphite-containing ink in the centrifuge 8 under the action of the third agitator 9.

[0031] In some specific implementations, such as Figure 1 As shown, the discharge end of the centrifugal separator 8 is also connected to a hopper 11 for receiving the separated graphite.

[0032] Working principle:

[0033] Add the negative electrode sheet to a container filled with heated pure water (3-11m). 3 In the mixing tank 1, at the start of operation, the lifting mechanism 5 places the filter screen 41 13-20mm above the stirring blade 21. The negative electrode is filled with 80% Vt. The first stirrer 2 and the second stirrer 3 rotate simultaneously, causing the copper foil and graphite powder to separate. The copper foil is placed on the filter screen 41 and lifted to the top by the lifting mechanism 5, then transferred to the recovery tank 6 to obtain the separated copper foil. The graphite forms a graphite slurry under the stirring action of the stirring blade 21 and the stirring knife 31. It is transported into the centrifugal separator 8 by the liquid outlet pipe 7. The separated graphite enters the silo 11 to obtain the separated graphite. At the same time, the water generated by centrifugation enters the filtration and sedimentation mechanism 13 through the water circulation pipe 12. After filtration, water without suspension is formed and enters the mixing storage tank 1 through the water circulation pipe 12 to realize water recycling and obtain continuously produced separated graphite powder and copper foil.

[0034] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of the invention. The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described; however, any combination of these technical features that does not contradict each other should be considered within the scope of this specification.

Claims

1. A lithium iron phosphate anode recycling device, characterized in that, include: The mixing tank (1) is equipped with a filter mechanism (4) for filtering copper foil, a first stirrer (2) and a second stirrer (3) from top to bottom inside the mixing tank (1); the bottom of the mixing tank (1) is connected to a liquid outlet pipe (7), which is connected to the feed end of a centrifugal separator (8), which is used to separate graphite.

2. The lithium iron phosphate negative electrode sheet recovery device according to claim 1, characterized by, The first stirrer (2) includes a first motor (22), a first stirring shaft (23), and stirring blades (21). 3.The lithium iron phosphate negative electrode sheet recovery device according to claim 2, characterized in that, The filtration mechanism (4) is located above the stirring blade (21) and includes a filter screen (41); the filter screen (41) is fixedly connected to the lifting mechanism (5). 4.The lithium iron phosphate negative electrode sheet recovery device according to claim 2, characterized by, The second stirrer (3) includes a second motor (32), a second stirring shaft (33), and a stirring blade (31). 5.The lithium iron phosphate negative electrode sheet recovery device according to claim 4, characterized in that, The number of the second stirrers (3) is at least 2. 6.The lithium iron phosphate negative electrode sheet recovery device according to claim 5, characterized in that, The centrifuge (8) is equipped with a feeding screw mechanism (10), which performs solid-liquid separation on the graphite-containing ink in the centrifuge (8) under the action of the third stirrer (9). 7.The lithium iron phosphate negative electrode sheet recovery device according to claim 6, characterized by, The centrifugal separator (8) has a filtration and sedimentation mechanism (13) at its lower outlet, which is connected to the stirring tank (1) through a water circulation pipe (12). 8.The lithium iron phosphate negative electrode sheet recovery device according to claim 7, characterized by, The centrifugal separator (8) is also connected to a hopper (11) at its discharge end for receiving the separated graphite.

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