Accurate separation treatment system for retired lithium battery

Abstract

The utility model discloses a precise separation treatment system for retired lithium batteries, which is applied to the technical field of waste battery recovery. Comprising an automatic shell disassembling module, an intelligent positive and negative pole piece sorting module, a positive pole piece powder removing module, a negative pole piece powder removing module and an electrolyte and diaphragm removing module, the automatic shell disassembling module is connected with the electrolyte and diaphragm removing module, and the electrolyte and diaphragm removing module is further connected with the intelligent positive and negative pole piece sorting module. And the intelligent positive and negative pole piece sorting module is also connected with the positive pole piece powder removing module and the negative pole piece powder removing module. The device disclosed by the utility model integrates the functions of automatically disassembling a shell, removing a diaphragm and electrolyte, sorting positive and negative pole pieces and removing powder from the pole pieces, can obtain high-purity positive and negative pole powder, and simultaneously realizes efficient recovery of substances such as a copper current collector and an aluminum current collector.

Description

Technical Field

[0001] The utility model relates to the technical field of waste battery recycling, and more specifically to a system for accurately separating and processing retired lithium batteries. Background Art

[0002] The rapid development of the new energy industry has driven the rapid growth of the lithium battery industry. As the type of power battery with the highest market share, lithium-ion batteries have been widely used in various industries. Limited by technology and battery performance, the service life of lithium-ion batteries is generally 3 to 5 years. Therefore, in the foreseeable development cycle in the future, a large number of retired and discarded lithium-ion batteries will appear. Research on the recycling and utilization technology of waste lithium battery resources can not only improve the efficiency of natural resource utilization, reduce production costs, and reduce environmental pollution, but also alleviate the resource demand pressure brought by the new energy industry. As a highly integrated energy storage device, lithium-ion batteries have a complex internal structure and multiple components. Due to the late start of current recycling technology research and the fact that the lithium battery recycling cycle has not yet fully arrived, how to safely and efficiently achieve large-scale disassembly of discarded lithium-ion batteries is the key issue of current pretreatment recycling. The traditional pretreatment method is to discharge and disassemble the battery pack, manually sort out the positive and negative electrodes of the battery, and then separate the positive and negative active materials from the current collector. This process is inefficient and unsafe, and it is difficult to achieve industrialization.

[0003] Chinese patent CN 112961984 A discloses a process for selectively recovering the collector of waste lithium-ion batteries, wherein the waste lithium-ion batteries are discharged, dried, incinerated, crushed, screened, and ball-milled to obtain the ball-milled material, and the ball-milled material is washed and magnetically separated to obtain a low-magnetic collector copper-aluminum mixture, and the collector copper-aluminum mixture is slurried and shaken to obtain collector copper and collector aluminum respectively. No new impurity ions are introduced in the whole separation process of this process, which greatly simplifies the subsequent impurity removal process, improves the purity of the copper-aluminum collector, and improves the sales value of the collector. However, the main purpose of this process is to obtain the copper-aluminum collector, and the recovery of the positive electrode black powder is not taken seriously. It is first incinerated at high temperature and then screened with a large-aperture screen. The incineration process will make the copper collector brittle, and then after crushing, a large amount of impurities such as copper, aluminum, and graphite will inevitably enter the positive electrode black powder, resulting in a high impurity content in the positive electrode black powder, increasing the pressure of subsequent recovery of valuable metals, and the recovery rate of the copper-aluminum collector is also reduced. In addition, the process of first magnetic separation and then shaking table separation also has certain disadvantages. Since there is very little magnetic material in the material, very little magnetic material is selected by magnetic separation first, and a large amount of material is left unselected, which will increase unnecessary load and energy consumption in the magnetic separation section. Therefore, how to provide a precise separation and processing system for retired lithium batteries is an urgent problem to be solved by those skilled in the art. Utility Model Content

[0004] In view of this, the utility model provides a precise separation and processing system for retired lithium batteries to solve the problems existing in the prior art. It integrates the functions of automated shell disassembly, diaphragm and electrolyte removal, positive and negative electrode sheet sorting, and electrode sheet powder removal, thereby improving production efficiency and reducing pollution risks.

[0005] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0006] A system for accurately separating and processing retired lithium batteries, comprising an automated shell disassembly module, a positive and negative electrode sheet intelligent sorting module, a positive electrode sheet powder removal module, a negative electrode sheet powder removal module and an electrolyte and diaphragm removal module, wherein the automated shell disassembly module is connected to the electrolyte and diaphragm removal module, which is further connected to the positive and negative electrode sheet intelligent sorting module, which is further connected to the positive electrode sheet powder removal module and the negative electrode sheet powder removal module.

[0007] Optionally, the shell automated disassembly module includes a shell disassembly device and a battery shell waste box, the battery shell waste box is arranged below the shell disassembly device, and the shell disassembly device is connected to the electrolyte and diaphragm removal module.

[0008] Optionally, the electrolyte and diaphragm removal module includes a first pyrolysis furnace, a secondary combustion chamber, a third cyclone dust collector, a heat exchanger, a third bag dust collector, an alkali solution spray tower, a stirring tank and a plate and frame filter press connected in sequence, and the first pyrolysis furnace is connected to the shell automatic disassembly module and the positive and negative electrode intelligent sorting module.

[0009] Optionally, the alkali solution spray tower is also connected to a third induced draft fan.

[0010] Optionally, a battery cell conveyor belt is provided between the first pyrolysis furnace and the shell automated disassembly module.

[0011] Optionally, the positive and negative electrode sheet intelligent sorting module includes a disperser, a linear screening machine and an intelligent sorting device connected in sequence, the disperser is connected to the shell automatic disassembly module, and the intelligent sorting device is connected to the positive electrode sheet de-powdering module and the negative electrode sheet de-powdering module.

[0012] Optionally, the positive electrode sheet de-powdering module includes a second pyrolysis furnace, a first hammer crusher, a first drum screen, a first cyclone dust collector, a first bag dust collector and a first induced draft fan connected in sequence, and the second pyrolysis furnace is connected to the positive and negative electrode sheet intelligent sorting module.

[0013] Optionally, the negative electrode sheet de-powdering module comprises a second hammer crusher, a second drum screen, a second cyclone dust collector, a second bag dust collector and a second induced draft fan which are connected in sequence, and the second hammer crusher is connected to the positive and negative electrode sheet intelligent sorting module.

[0014] It can be seen from the above technical solutions that, compared with the prior art, the utility model provides a system for accurately separating and processing retired lithium batteries, which has the following beneficial effects:

[0015] (1) The utility model first disassembles the battery casing, and then removes the diaphragm and electrolyte by low-temperature pyrolysis, which effectively reduces the impurity doping in the positive and negative electrode powders and the copper and aluminum current collectors;

[0016] (2) The utility model uses a medium-low temperature heat treatment method to remove the electrolyte and the carbonized diaphragm, which not only removes the hazards of the electrolyte and the influence of diaphragm impurities, but also avoids the decomposition of PVDF, which causes a large amount of positive electrode powder to fall off from the aluminum current collector during the material dispersion process. The positive electrode powder obtained by the utility model has high purity and only a small amount of positive and negative electrode powder mixture, while achieving efficient recovery of materials such as copper and aluminum current collectors;

[0017] (3) The utility model does not use chemical reagents in the entire process, and the pyrolysis tail gas is treated with flue gas, which is a green and efficient separation method. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings in the following description are only embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0019] Figure 1 This is a schematic diagram of the precise separation and processing system for retired lithium batteries of the utility model;

[0020] In the figure: 1-shell disassembly equipment, 2-first pyrolysis furnace, 3-disperser, 4-linear screening machine, 5-intelligent sorting equipment, 6-second pyrolysis furnace, 7-first hammer crusher, 8-first drum screen, 9-first cyclone dust collector, 10-first bag dust collector, 11-first induced draft fan, 12-second hammer crusher, 13-second drum screen, 14-second cyclone dust collector, 15-second bag dust collector, 16-second induced draft fan, 17-secondary combustion chamber, 18-third cyclone dust collector, 19-heat exchanger, 20-third bag dust collector, 21-alkali solution spray tower, 22-third induced draft fan, 23-mixing tank, 24-plate and frame filter press. DETAILED DESCRIPTION

[0021] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0022] The utility model discloses a system for accurately separating and processing retired lithium batteries. Figure 1 As shown, it includes an automatic shell disassembly module, a positive and negative electrode sheet intelligent sorting module, a positive electrode sheet powder removal module, a negative electrode sheet powder removal module and an electrolyte and diaphragm removal module. The automatic shell disassembly module is connected to the electrolyte and diaphragm removal module, and the electrolyte and diaphragm removal module is also connected to the positive and negative electrode sheet intelligent sorting module. The positive and negative electrode sheet intelligent sorting module is also connected to the positive electrode sheet powder removal module and the negative electrode sheet powder removal module.

[0023] Furthermore, the shell automated disassembly module includes a shell disassembly device 1 and a battery shell waste box. The battery shell waste box is arranged below the shell disassembly device 1. The shell disassembly device 1 is connected to the electrolyte and diaphragm removal module.

[0024] Furthermore, the electrolyte and diaphragm removal module includes a first pyrolysis furnace 2, a secondary combustion chamber 17, a third cyclone dust collector 18, a heat exchanger 19, a third bag filter 20, an alkali solution spray tower 21, a stirring tank 23 and a plate and frame filter press 24 which are connected in sequence. The first pyrolysis furnace 2 is connected to the shell automatic disassembly module and the positive and negative electrode intelligent sorting module.

[0025] Furthermore, the alkali solution spray tower 21 is also connected to a third induced draft fan 22 .

[0026] Furthermore, a battery cell conveyor belt is provided between the first pyrolysis furnace 2 and the shell automated disassembly module.

[0027] Furthermore, the positive and negative electrode sheet intelligent sorting module includes a disperser 3, a linear screening machine 4 and an intelligent sorting device 5 connected in sequence, the disperser 3 is connected to the shell automatic disassembly module, and the intelligent sorting device 5 is connected to the positive electrode sheet de-powdering module and the negative electrode sheet de-powdering module.

[0028] Furthermore, the positive electrode sheet de-powdering module includes a second pyrolysis furnace 6, a first hammer crusher 7, a first drum screen 8, a first cyclone dust collector 9, a first bag dust collector 10 and a first induced draft fan 11 which are connected in sequence, and the second pyrolysis furnace 6 is connected to the positive and negative electrode sheet intelligent sorting module.

[0029] Furthermore, the negative electrode sheet de-powdering module includes a second hammer crusher 12, a second drum screen 13, a second cyclone dust collector 14, a second bag dust collector 15 and a second induced draft fan 16 which are connected in sequence, and the second hammer crusher 12 is connected to the positive and negative electrode sheet intelligent sorting module.

[0030] The working principle of this utility model:

[0031] The shell of waste lithium-ion batteries is removed through the shell automated disassembly module, and then the diaphragm and electrolyte are removed through the electrolyte and diaphragm removal module to facilitate the subsequent sorting of positive and negative electrode sheets. The positive and negative electrode sheets are then separated through the positive and negative electrode sheet intelligent sorting module. Finally, the positive and negative electrode sheets are de-powdered through the positive electrode sheet de-powdering module and the negative electrode sheet de-powdering module respectively to obtain positive and negative electrode powders as well as aluminum and copper current collectors. The pyrolysis exhaust gas generated in the electrolyte and diaphragm removal module is purified by the electrolyte and diaphragm removal module.

[0032] In one embodiment of the utility model, the waste lithium-ion battery is removed from the battery shell by the shell disassembly device 1, the shell is stored in the battery shell waste box, and the remaining battery cells are conveyed to the subsequent module by the battery cell conveyor belt;

[0033] The battery cells are transported to the first pyrolysis furnace 2, which is an electric heating rotary furnace. The lithium battery cells are pyrolyzed under medium and low temperature conditions in a nitrogen atmosphere. The purpose is to pyrolyze and volatilize the electrolyte for harmless treatment and carbonize the diaphragm. The temperature of low-temperature pyrolysis is lower than the decomposition temperature of PVDF. The purpose is to prevent the positive electrode powder from falling off during the dispersion process, resulting in a large amount of doping of the positive and negative electrode powders. After pyrolysis, only the positive and negative electrodes are left in the mixed material. The flue gas generated by the pyrolysis electrolyte and the diaphragm enters the secondary combustion chamber 17 for full combustion to remove organic matter in the pyrolysis flue gas and prevent it from causing harm to the environment. The third cyclone dust collector 18 preliminarily removes dust in the flue gas, and then the heat exchanger 19 is used to cool the pyrolysis flue gas. The cooled pyrolysis flue gas enters the third bag filter 20 for further dust removal. The alkali solution spray tower 21 is used to remove acidic substances in the pyrolysis flue gas. The alkaline wastewater after spraying enters the stirring tank 23, and CaCl2 is added to the stirring tank. The spray wastewater is defluorinated to generate CaF2 precipitate. The wastewater after the reaction is separated by a plate and frame filter press 24 to obtain defluorinated waste residue and defluorinated wastewater; the alkali solution spray tower 21 is connected to the third induced draft fan 22 to promote the circulation of flue gas in the pipeline.

[0034] The positive and negative electrode sheets after pyrolysis are separated in the positive and negative electrode sheet intelligent sorting module, which is convenient for the subsequent separation of the current collector and the coating material; first, the positive and negative electrode sheets after low-temperature pyrolysis to remove the electrolyte and the diaphragm are broken up by the disperser 3, in order to disperse the remaining positive and negative electrode sheets to facilitate their effective identification in the intelligent sorting system. In this process, the positive electrode powder, the negative electrode powder, and the diaphragm powder carbonized after low-temperature pyrolysis will inevitably fall off; then the linear screening machine 4 is used to screen and remove the powder material, and the remaining flaky material enters the intelligent sorting equipment 5 to separate the positive and negative electrode sheets.

[0035] The sorted positive electrode sheets are sent to the second pyrolysis furnace 6 for high-temperature pyrolysis, the purpose of which is to decompose PVDF at high temperature and facilitate the separation of positive electrode materials and current collectors; wherein, the pyrolysis is carried out under an inert atmosphere such as nitrogen, and the pyrolysis temperature is about 500°C; the pyrolyzed positive electrode sheets are crushed in the first hammer crusher 7, the purpose of which is to separate the positive electrode material and the current collector, so that the current collector is crushed into small particles for subsequent screening. The crushed materials are sent to the first drum screen 8 for separation, and positive electrode powder and aluminum current collector are obtained respectively; the first drum screen 8 is connected to the first cyclone dust collector 9 and the first bag dust collector 10, the purpose of which is to collect positive electrode dust in the flue gas; the first bag dust collector 10 is connected to the first induced draft fan 11 to promote the circulation of flue gas in the pipeline.

[0036] The purpose of the negative electrode sheet de-powdering module is to separate the copper current collector and the negative electrode powder of the negative electrode sheet. Since the bonding performance between the negative electrode powder and the copper current collector is weak, there is no need to perform pyrolysis treatment on the negative electrode sheet. The negative electrode sheet is directly placed in the second hammer crusher 12 for crushing. The purpose is to separate the negative electrode material and the current collector, so that the current collector is crushed into small particles for subsequent screening; the crushed materials are sent to the second drum screen 13 for separation to obtain negative electrode powder and aluminum current collector respectively; the second drum screen 13 is connected to the second cyclone dust collector 14 and the second bag dust collector 15, and the purpose is to collect negative electrode dust in the flue gas. The bag dust collector is connected to the second induced draft fan 16 to promote the circulation of flue gas in the pipeline.

[0037] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0038] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A system for accurately separating and processing retired lithium batteries, characterized in that: It includes an automatic shell disassembly module, a positive and negative electrode sheet intelligent sorting module, a positive electrode sheet powder removal module, a negative electrode sheet powder removal module and an electrolyte and diaphragm removal module. The automatic shell disassembly module is connected to the electrolyte and diaphragm removal module, and the electrolyte and diaphragm removal module is also connected to the positive and negative electrode sheet intelligent sorting module. The positive and negative electrode sheet intelligent sorting module is also connected to the positive electrode sheet powder removal module and the negative electrode sheet powder removal module.

2. A system for accurately separating and processing retired lithium batteries according to claim 1, characterized in that: The shell automated disassembly module comprises a shell disassembly device (1) and a battery shell waste box, wherein the battery shell waste box is arranged below the shell disassembly device (1), and the shell disassembly device (1) is connected to the electrolyte and diaphragm removal module.

3. A system for accurately separating and processing retired lithium batteries according to claim 1, characterized in that: The electrolyte and diaphragm removal module comprises a first pyrolysis furnace (2), a secondary combustion chamber (17), a third cyclone dust collector (18), a heat exchanger (19), a third bag filter (20), an alkali solution spray tower (21), a stirring tank (23) and a plate and frame filter press (24) which are connected in sequence, and the first pyrolysis furnace (2) is connected to the shell automatic disassembly module and the positive and negative electrode intelligent sorting module.

4. A system for accurately separating and processing retired lithium batteries according to claim 3, characterized in that: The alkali solution spray tower (21) is also connected to a third induced draft fan (22).

5. A system for accurately separating and processing retired lithium batteries according to claim 3, characterized in that: A battery cell conveyor belt is provided between the first pyrolysis furnace (2) and the shell automated disassembly module.

6. A system for accurately separating and processing retired lithium batteries according to claim 1, characterized in that: The positive and negative electrode sheet intelligent sorting module comprises a disperser (3), a linear screening machine (4) and an intelligent sorting device (5) which are connected in sequence, the disperser (3) is connected to the shell automatic disassembly module, and the intelligent sorting device (5) is connected to the positive electrode sheet de-powdering module and the negative electrode sheet de-powdering module.

7. A system for accurately separating and processing retired lithium batteries according to claim 1, characterized in that: The positive electrode sheet de-powdering module comprises a second pyrolysis furnace (6), a first hammer crusher (7), a first drum screen (8), a first cyclone dust collector (9), a first bag dust collector (10) and a first induced draft fan (11) which are connected in sequence, and the second pyrolysis furnace (6) is connected to the positive and negative electrode sheet intelligent sorting module.

8. The system for accurately separating and processing retired lithium batteries according to claim 1, characterized in that: The negative electrode sheet powder removal module comprises a second hammer crusher (12), a second roller connected in sequence a screen (13), a second cyclone dust collector (14), a second bag dust collector (15) and a second induced draft fan (16), The second hammer crusher (12) is connected to the positive and negative electrode sheet intelligent sorting module.

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