Equipment for separating negative electrode material and current collector of lithium ion battery

Abstract

The invention discloses equipment for separating a negative electrode material and a current collector of a lithium ion battery, and relates to the technical field of separation equipment, the equipment comprises a stirring separator and a cleaning screener which are integrally connected, continuous separation can be realized, two groups of stirring mechanisms in the stirring separator rotate reversely, and a short-flow prevention partition plate is arranged between the two groups of stirring mechanisms; the flow path of the solution can be limited, the retention time is prolonged, the stirring and washing effects are improved, and the separation of the current collector is promoted; the spoilers on the inner wall of the separator shell can prevent the solution from rotating in the same direction to form a swirling phenomenon and laminar flow, and can promote mutual friction and collision of solids in the separator shell and contact of the solids with the stirring paddle, so that the stirring and separating effects are enhanced.

Description

Technical Field

[0001] The present invention relates to the technical field of separation equipment, and in particular to equipment for separating negative electrode materials and current collectors of lithium-ion batteries. Background Art

[0002] Commonly used negative electrode sheets of lithium batteries mainly include current collectors (copper foil), negative electrode materials (graphite) and binders. The negative electrode materials are coated on the surface of the current collector by the binder. Since graphite has a wide source in the traditional sense and has low added value in recycling, negative electrode recycling in actual applications mainly targets the recovery of metal copper in the current collector in negative electrode materials, resulting in reduced or wasted graphite activity. At present, negative electrode recycling is mainly divided into three methods: wet method, pyrolysis and mechanical separation. Wet recycling uses acid and alkali treatment to leach negative electrode metal materials with a high recovery rate, but the acid and alkali treatment process is difficult, has high safety risks, and requires large investment in environmental protection facilities. The pyrolysis recovery process is simple and uses high-temperature incineration or pyrolysis to remove graphite and binder from the negative electrode sheet and separate metallic copper, but there are problems such as high energy consumption and low recovery rate; mechanical separation uses physical crushing and sorting to separate graphite and metallic copper, but it is affected by the binder and cannot be completely separated. The metal and graphite are mixed with each other, the product purity is affected, and the equipment requirements are high.

[0003] In response to these problems, the patent document with publication number CN114530641A in the prior art discloses a method for recycling the negative electrodes of waste lithium-ion batteries, which separates the positive electrode material and the current collector by water immersion and then removes the impurity ions in the negative electrode material by organic acid immersion and carbon dioxide; the patent document with publication number CN 111792642A discloses a method and equipment for stripping the negative electrode sheets of retired batteries and deep impurity removal of graphite, which separates the current collector and graphite by water washing in a kettle with a filter basket, thereby realizing intermittent operation of the separation process.

[0004] However, in the above-mentioned prior art, the equipment used to separate the positive electrode material and the current collector is often just a single stirring device. Although the single stirring can achieve separation to a certain extent, the separation effect is not thorough enough. A small amount of negative electrode material is often still attached to the current collector, resulting in a high impurity content in the final separated current collector and a poor recovery effect. Summary of the invention

[0005] The purpose of the present invention is to provide a device for separating negative electrode materials and current collectors of lithium-ion batteries to solve the following technical problems: How to achieve better separation of negative electrode materials and current collectors in lithium-ion batteries.

[0006] The purpose of the present invention can be achieved through the following technical solutions: A device for separating negative electrode materials and current collectors of lithium-ion batteries, comprising a stirring separator and a cleaning sifter, wherein: The stirring separator comprises a separator shell, a separator inlet arranged at the top of one end of the separator shell, and a separator outlet arranged at the top of the other end of the separator shell and having a height lower than the separator inlet; two sets of counter-rotating stirring mechanisms 1 and 2 are arranged inside the separator shell, and a jet mechanism is arranged at the bottom; The cleaning screen comprises a screen housing, a screen inlet arranged at the top of one end of the screen housing, a fluid collector outlet and a suspension outlet arranged at the bottom of the other end of the screen housing; a linear vibrating screen and a cleaning mechanism arranged above the linear vibrating screen are arranged in the screen housing; The separator outlet and the screener inlet in the stirring separator are connected through a pipeline.

[0007] In a further embodiment of the present invention, the stirring mechanism 1 and the stirring mechanism 2 are arranged in parallel, and the two have the same structure, and are both composed of a stirring shaft, a motor for driving the stirring shaft to rotate, and a stirring paddle installed on the stirring shaft.

[0008] In a further embodiment of the present invention, brushes are installed on the stirring paddles in the stirring mechanism 1 and the stirring mechanism 2.

[0009] In a further embodiment of the present invention, the jet mechanism comprises a jet tube, an input end of the jet tube is connected to a water inlet pump, and jet nozzles facing the stirring mechanism 1 and the stirring mechanism 2 are installed on the tube wall.

[0010] In a further embodiment of the present invention, a short-flow prevention baffle is provided between the stirring mechanism 1 and the stirring mechanism 2.

[0011] In a further embodiment of the present invention, a spoiler is provided on the inner wall of the separator housing.

[0012] In a further embodiment of the present invention, the linear vibrating screen comprises a screen and a vibrating mechanism disposed below the screen, one end of the screen is disposed at the inlet of the screener, and the other end is disposed at the outlet of the collector.

[0013] In a further embodiment of the present invention: the aperture size of the screen is smaller than the size of the crushed material, and the inclination angle is greater than °C.

[0014] In a further embodiment of the present invention, the cleaning mechanism includes a plurality of flushing nozzles and a water pump connected to the flushing nozzles. The flushing nozzles are installed on the top of the rear section of the linear vibrating screen in the form of a gantry.

[0015] Beneficial effects of the present invention: The device for separating negative electrode materials and current collectors of lithium-ion batteries of the present invention comprises an integrally connected stirring separator and a cleaning screen, which can realize continuous separation. Two sets of stirring mechanisms in the stirring separator rotate in opposite directions, and an anti-short-flow baffle is arranged between the two, which can limit the flow path of the solution, increase the residence time, enhance the stirring and washing effect, and promote the separation of the current collector; the spoiler on the inner wall of the separator shell can prevent the solution from rotating in the same direction to form vortexes and laminar flow, and can promote the mutual friction and collision of solids in the separator shell and the contact with the stirring paddle, thereby enhancing the stirring and separation effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The present invention will be further described below in conjunction with the accompanying drawings.

[0017] Figure 1 It is a schematic structural diagram of a stirring separator in a device for separating negative electrode materials and current collectors of lithium-ion batteries according to the present invention; Figure 2 It is a structural schematic diagram of a cleaning screen in a device for separating negative electrode materials and current collectors of lithium-ion batteries according to the present invention.

[0018] In the figure: 1. stirring separator; 101. separator housing; 102. separator inlet; 103. separator outlet; 104. jet tube; 105. stirring mechanism 1; 106. stirring mechanism 2; 107. brush; 108. spoiler; 109. anti-short flow baffle; 2. cleaning screener; 201. screener housing; 202. screener inlet; 203. collector outlet; 204. suspension outlet; 205. screen; 206. vibration mechanism; 207. flushing nozzle. DETAILED DESCRIPTION

[0019] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0020] See also Figure 1-2 The present invention discloses a device for separating negative electrode materials and current collectors of lithium-ion batteries, including a stirring separator 1 and a cleaning screen 2, both of which will be introduced in detail below.

[0021] Figure 1The stirring separator 1 comprises a separator shell 101 , a separator inlet 102 is arranged at the top of the left end, and a separator outlet 103 is arranged at the top of the right end, and the height of the separator outlet 103 is lower than the height of the separator inlet 102 to ensure that the solution can flow out from the separator outlet 103 by itself.

[0022] The separator housing 101 is provided with a stirring mechanism 1 105 and a stirring mechanism 2 106 having the same structure in parallel. The specific structures of the two are not limited, and only need to meet the stirring requirements. For example, the stirring mechanism 1 105 and the stirring mechanism 2 106 are both a combination structure including a stirring shaft, a motor driving the stirring shaft to rotate, and a stirring paddle installed on the stirring shaft, wherein the motor is installed at the outer top of the separator housing 101, and the stirring shaft is vertically arranged inside the separator housing 101 and the upper end is connected to the output end of the motor. When the motor starts to drive the stirring shaft to rotate, the stirring shaft drives the stirring paddle to rotate accordingly, thereby achieving a stirring effect. The stirring paddles in the stirring mechanism 1 105 and the stirring mechanism 2 106 are both provided with a brush 107 to enhance the stirring and washing effect; an anti-short flow baffle 109 is provided between the stirring mechanism 1 105 and the stirring mechanism 2 106, and the anti-short flow baffle 109 is used to limit the flow path of the solution, increase the residence time, and prevent the solution from flowing directly from the upper part of the tank to the separator outlet 103.

[0023] A jet tube 104 is installed at the bottom of the separator shell 1, and the input end of the jet tube 104 is connected to a water inlet pump, and a plurality of jet nozzles are installed on the jet tube 104. The jet tube 104, the water inlet pump and the jet nozzle constitute a jet mechanism. The water inlet pump pumps water into the jet tube 104, and the water is sprayed into the separator shell 101 through the jet nozzle to achieve water inlet; at the same time, a spoiler 108 is also installed on the inner wall of the separator shell 101 to prevent the solution from rotating in the same direction to form vortexes and laminar flow, and can promote the mutual friction and collision of solids in the separator shell 101 and the contact with the stirring paddle, thereby enhancing the stirring and separation effect.

[0024] The method of using the stirring separator 1 is as follows: the crushed material of the battery negative electrode sheet is put into the separator shell 101 from the separator inlet 102, and then a certain proportion of water is injected into the separator shell 101 through the jet mechanism, and then the stirring mechanism 1 105 and the stirring mechanism 2 106 are turned on, and the stirring paddles of the two are rotated in opposite directions. The brush 107 on the stirring paddle stirs and separates the crushed material, thereby separating the current collector and the negative electrode material of the crushed material. After the stirring is completed, the mixed solution of the current collector, the negative electrode material and water flows out from the separator outlet 103 and then enters the cleaning screen 2.

[0025] Figure 2The cleaning screen 2 comprises a screen housing 201. A screen inlet 202 is arranged at the top of the right end of the screen housing 201, and a fluid collector outlet 203 and a suspension outlet 204 are arranged at the bottom of the left end. The separator outlet 103 in the stirring separator 1 is connected to the screen inlet 202 through a pipeline to facilitate material transfer. A linear screen 205 is arranged in the cleaning screen 2, and a vibration mechanism 206 is arranged at the bottom of the cleaning screen 2 to drive the screen 205 to vibrate. The screen 205 Together with the vibration mechanism 206, a linear vibrating screen machine is formed; the specific structure of the vibration mechanism 206 is not limited, it only needs to meet the vibration requirements. For example, the vibration mechanism 206 can use a vibrating machine; one end of the screen 205 is connected to the screen inlet 202, and the other end is connected to the collector outlet 203, thereby dividing the interior of the cleaning screen housing 201 into two upper and lower parts; the aperture size of the screen 205 is smaller than the size of the crushed material, and the inclination angle is greater than 2°, so that the collector can slide smoothly to the collector outlet 203.

[0026] A plurality of flushing nozzles 207 are arranged on the inner top wall of the screener housing 201, and the flushing nozzles 207 are connected to a water pump to achieve water inlet, and the flushing nozzles 207 and the water pump form a flushing mechanism; the flushing nozzles 207 are installed in the form of a gantry on the top of the rear section of the linear vibrating screen machine to flush the collector during the vibrating screen process.

[0027] The method of using the cleaning screen 2 is as follows: the mixed solution enters the screen housing 201 through the screen inlet 202 and falls on the screen 205. The screen 205 vibrates under the action of the vibration mechanism 206, and the flushing nozzle 207 flushes the rear half of the screen 205, thereby leaving the collector on the screen 205, and the negative electrode material and water in the mixed solution fall from the mesh of the screen 205. Finally, the screened collector is discharged from the collector outlet 203, and the suspension of the negative electrode material and water is discharged from the suspension outlet 204, thereby realizing the separation of the collector and the negative electrode material.

[0028] In the description of the present invention, it should be understood that the terms "upper", "lower", "left", "right", etc. indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction and a specific direction structure and operation, and therefore, cannot be understood as a limitation on the present invention. In addition, "first" and "second" are only for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0029] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", etc. should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0030] The above is a detailed description of an embodiment of the present invention, but the content is only a preferred embodiment of the present invention and cannot be considered to limit the scope of implementation of the present invention. All equivalent changes and improvements made within the scope of the present invention should still fall within the scope of the patent coverage of the present invention.

Claims

1. A device for separating negative electrode materials and current collectors of lithium-ion batteries, characterized in that: It includes a stirring separator 1 and a cleaning sifter 2, wherein: The stirring separator 1 comprises a separator housing 101, a separator inlet 102 arranged at the top of one end of the separator housing 101, and a separator outlet 103 arranged at the top of the other end of the separator housing and having a height lower than the separator inlet 102; two sets of counter-rotating stirring mechanisms 1 105 and 106 are arranged inside the separator housing 1, and a jet mechanism is arranged at the bottom; The cleaning screen 2 comprises a screen housing 201, a screen inlet 202 arranged at the top of one end of the screen housing 201, a collector outlet 203 and a suspension outlet 204 arranged at the bottom of the other end of the screen housing; a linear vibrating screen and a cleaning mechanism arranged above the linear vibrating screen are arranged in the screen housing 201; The separator outlet 103 in the stirring separator 1 is connected to the screener inlet 202 via a pipeline.

2. The device for separating negative electrode materials and current collectors of lithium-ion batteries according to claim 1, characterized in that: The stirring mechanism 1 105 and the stirring mechanism 2 106 are arranged in parallel, and the two have the same structure, and are both composed of a stirring shaft, a motor driving the stirring shaft to rotate, and a stirring paddle installed on the stirring shaft.

3. The device for separating negative electrode materials and current collectors of lithium-ion batteries according to claim 2, characterized in that: Brushes 107 are installed on the stirring paddles of the stirring mechanism 1 105 and the stirring mechanism 2 106 .

4. The device for separating negative electrode materials and current collectors of lithium-ion batteries according to claim 1, characterized in that: The jet mechanism comprises a jet tube 104 , the input end of the jet tube 104 is connected to a water inlet pump, and jet nozzles facing the stirring mechanism 1 105 and the stirring mechanism 2 106 are installed on the tube wall.

5. The device for separating negative electrode materials and current collectors of lithium-ion batteries according to claim 1, characterized in that: An anti-short flow baffle 109 is provided between the stirring mechanism 1 105 and the stirring mechanism 2 106 .

6. The device for separating negative electrode materials and current collectors of lithium-ion batteries according to claim 1, characterized in that: A spoiler 108 is disposed on the inner wall of the separator housing 101 .

7. The device for separating negative electrode materials and current collectors of lithium-ion batteries according to claim 1, characterized in that: The linear vibrating screen includes a screen 205 and a vibrating mechanism 206 disposed below the screen 205 . One end of the screen is disposed at the screen inlet 202 , and the other end is disposed at the collector outlet 203 .

8. The device for separating negative electrode materials and current collectors of lithium-ion batteries according to claim 7, characterized in that: The aperture size of the screen 205 is smaller than the size of the crushed material, and the inclination angle is greater than 2°.

9. The device for separating negative electrode materials and current collectors of lithium-ion batteries according to claim 1, characterized in that: The cleaning mechanism includes a plurality of flushing nozzles 207 and a water pump connected to the flushing nozzles 207. The flushing nozzles 207 are installed on the top of the rear section of the linear vibrating screen in the form of a gantry.

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