Continuous mechanochemical industrial lithium extraction system for retired lithium battery and working method of continuous mechanochemical industrial lithium extraction system

Abstract

The invention discloses a continuous mechanochemical industrial lithium extraction system for retired lithium batteries and a working method of the continuous mechanochemical industrial lithium extraction system. The lithium extraction system comprises a disassembling unit, a crushing unit, a loading unit, a continuous mechanochemical unit and a leaching unit which are sequentially arranged upstream and downstream. According to the system, industrial continuous production can be realized, the production scale and the production efficiency are greatly increased, industrial large-scale application can be carried out, the industrialized breakthrough of mechanochemical lithium extraction of the retired lithium battery is realized, and the practical problem that the existing mechanochemical lithium extraction production scale is limited is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of retired lithium battery processing, and in particular to a retired lithium battery continuous mechanochemical industrial lithium extraction system and a working method thereof. Background Art

[0002] With the vigorous development of the new energy vehicle industry, the resource application of retired lithium batteries has gradually become a hot topic in industry research. For retired power lithium batteries, lithium iron phosphate batteries have gradually begun to become the mainstream choice in the market. The valuable metals of retired lithium batteries are mainly enriched in the positive electrode materials. The positive electrode materials often use hydrometallurgical processes to recover valuable metals, which produces a lot of wastewater and the separation and purification process is complicated. However, due to the low price of lithium, it is difficult to achieve the effective utilization of lithium iron phosphate batteries using traditional recycling methods. In recent years, studies have found that mechanochemical selective lithium extraction technology can reduce extraction costs and increase the efficiency and purity of lithium extraction. However, at present, mechanochemical selective lithium extraction technology is still in the research stage, the processing scale is small, and it is difficult to achieve industrial production. Summary of the invention

[0003] The present invention aims to solve one of the technical problems in the related art at least to a certain extent.

[0004] To this end, an embodiment of the present invention proposes a continuous mechanochemical industrial lithium extraction system for retired lithium batteries and a working method thereof.

[0005] In the first aspect, the present invention proposes a continuous mechanochemical industrial lithium extraction system for retired lithium batteries, comprising: A disassembly unit, wherein the disassembly unit disassembles the battery pack step by step to obtain the positive electrode sheet; A crushing unit is provided downstream of the disassembling unit, and the crushing unit crushes the positive electrode sheet to obtain positive electrode crushed material; A loading unit is arranged downstream of the crushing unit, and the loading unit packages the positive electrode crushed material and the grinding aid into a ball mill tank; A continuous mechanochemical unit is arranged downstream of the loading unit, the continuous mechanochemical unit comprises a plurality of parallel production lines, each of the production lines comprises a feed production line, a discharge production line and a plurality of mechanochemical treatment zones, and the plurality of mechanochemical treatment zones are arranged in series on the upper part of the feed production line; The leaching unit is arranged downstream of the continuous mechanochemical unit, and the leaching unit performs solid-liquid separation on the material processed by the continuous mechanochemical unit to extract and separate lithium.

[0006] Furthermore, the disassembly process of the disassembly unit includes appearance and leakage detection - removing the upper cover and battery pack discharge - removing the copper bus and wiring harness - removing the BMS and electronic accessories - removing the module fixing screws - removing the module upper cover and circuit board - module discharge - milling the bus and end side plates - disassembling the module - disassembling the battery cell - removing the positive electrode sheet.

[0007] Furthermore, the grinding aid includes one or more of an acidic leaching agent, an oxidizing agent, and an inorganic salt.

[0008] Furthermore, the mechanochemical treatment area includes a ball mill equipment body, a ball mill tank body, an automatic loading and unloading system and a control unit. The ball mill tank body is detachable and replaceable, and the control unit controls the automatic loading and unloading system to realize the loading and unloading operations of the ball mill tank body.

[0009] Furthermore, when feeding, the ball mill tank body is put on the machine, the ball mill equipment body enters the working state, and ball milling begins; when unloading, the ball milling is completed, the ball mill tank body is unloaded, and the ball mill equipment body enters the standby state.

[0010] Furthermore, during ball milling, the ball milling time is 0.5-2 h, and the rotation speed of the ball mill is 200-1000 rpm.

[0011] Furthermore, the ball milling equipment body is horizontal or vertical.

[0012] Furthermore, the automated loading and unloading system is a robotic arm.

[0013] Furthermore, the leaching unit adopts a water leaching process.

[0014] In a second aspect, the present invention provides a working method of the system provided in the first aspect, comprising the following steps: (a) Disassembling the retired battery pack to obtain the positive electrode sheet; (b) crushing the positive electrode sheet to obtain positive electrode crushed material; (c) packaging the positive electrode crushed material and the grinding aid into a ball mill tank; (d) The ball mill is placed on the machine, and after the ball milling is completed, lithium is extracted using a water leaching process.

[0015] Compared with the prior art, the beneficial effects of the present invention are: The system of the present invention can realize industrial continuous production, greatly increase the production scale and production efficiency, and can be applied on an industrial large scale, making an industrial breakthrough in the mechanochemical extraction of lithium from retired lithium batteries and solving the practical problem of limited production scale of existing mechanochemical extraction of lithium. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which: Figure 1 This is a schematic diagram of the structure of the continuous mechanochemical industrial lithium extraction system for retired lithium batteries of the present invention; Figure 2 It is a schematic diagram of the disassembly process of the disassembly unit of the present invention; Figure 3 This is a schematic diagram of the continuous mechanochemical unit of the present invention; Figure 4 This is a schematic diagram of the working process of the continuous mechanochemical industrial lithium extraction system for retired lithium batteries of the present invention. DETAILED DESCRIPTION

[0017] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0018] The following describes the continuous mechanochemical industrial lithium extraction system for retired lithium batteries and its working method proposed by the present invention in conjunction with the accompanying drawings.

[0019] like Figure 1 As shown, the continuous mechanochemical industrial lithium extraction system for retired lithium batteries of the present invention includes a disassembly unit, a crushing unit, a loading unit, a continuous mechanochemical unit and a leaching unit arranged in sequence upstream and downstream.

[0020] The disassembly unit disassembles the battery pack step by step, obtains the module from the battery pack, then obtains the battery cell from the module, and finally obtains the positive electrode sheet from the battery cell. Figure 2 As shown, the disassembly process of the disassembly unit includes appearance and leakage detection - removing the upper cover and battery pack discharge - removing the copper bus and wiring harness - removing the BMS and electronic accessories - removing the module fixing screws - removing the module upper cover and circuit board - module discharge - milling the bus and end side plates - disassembling the module - disassembling the battery cell - removing the positive electrode sheet.

[0021] The purpose of appearance inspection is to determine whether the retired battery pack is worth recycling. If the retired battery pack is severely damaged and cannot be recycled, no subsequent disassembly operation will be performed. The purpose of leakage detection is to detect whether the battery pack is leaking electricity to ensure the safety of subsequent disassembly operations. The process of milling the busbars and end panels can be operated by robots. After disassembling the module, the battery cell is obtained. After disassembling the battery cell, the core is obtained. The positive electrode sheet in the core is taken out to complete the disassembly operation.

[0022] The crushing unit is arranged downstream of the disassembling unit, and the crushing unit crushes the positive electrode sheet to obtain the positive electrode crushed material. In some embodiments, the crushing unit relies on a crusher to crush the positive electrode sheet to reduce the material particle size and obtain the crushed positive electrode sheet material.

[0023] The loading unit is set downstream of the crushing unit. The loading unit encapsulates the positive electrode crushed material and the grinding aid into the ball mill tank for subsequent continuous mechanochemical unit loading. The amount of grinding aid added is 0.01%-10% of the mass of the positive electrode crushed material.

[0024] Grinding aids include one or more of acidic leaching agents, oxidants, and inorganic salts, that is, different types of grinding aids can be used alone or in combination. Acidic leaching agents include inorganic acids and organic acids, wherein inorganic acids include sulfuric acid, hydrochloric acid, phosphoric acid, nitric acid, etc., organic acids include salicylic acid, formic acid, acetic acid, oxalic acid, citric acid, malic acid, tartaric acid, ascorbic acid, etc., oxidants include hydrogen peroxide, sodium sulfite, sodium persulfate, etc., and inorganic salts include sodium chloride, ferric chloride, etc.

[0025] The grinding aid of the invention has small addition amount, low cost, low environmental pollution, high selectivity and an extraction rate of more than 95%.

[0026] In some embodiments, ball milling is performed in the presence of a grinding aid and ball milling balls, wherein the ball milling balls include one or more of corundum balls, ceramic balls, quartz balls, and agate balls.

[0027] The continuous mechanochemical unit is arranged downstream of the loading unit, and the continuous mechanochemical unit includes multiple parallel production lines, each production line includes a feed production line, a discharge production line and multiple mechanochemical treatment zones, and the multiple mechanochemical treatment zones are arranged in series on the upper part of the feed production line.

[0028] Specifically, the continuous mechanochemical unit includes multiple parallel lines, and multiple parallel production lines realize the planned processing of retired lithium batteries. Each production line includes a feed production line, a discharge production line and multiple mechanochemical treatment areas, wherein the feed production line is connected to the loading unit, the discharge unit is connected to the leaching unit, and multiple mechanochemical treatment areas are arranged in series on the upper part of the feed production line, and multiple mechanochemical discharge areas are arranged in a continuous arrangement. The setting of multiple mechanochemical treatment areas improves the scale of industrial processing. After the ball-milled positive electrode crushed material is packaged into the ball mill tank with the grinding aid, it enters from the feed production line. After the ball milling is completed, the ball-milled material goes out from the discharge production line.

[0029] In some embodiments, Figure 3 As shown, the continuous mechanochemical unit includes m (m>2) parallel production lines, each of which includes n (n>4) mechanochemical treatment zones.

[0030] The setting of the continuous mechanochemical unit in the present invention realizes the continuous operation of feeding, ball milling and discharging, improves the efficiency and realizes the continuous large-scale processing of retired lithium batteries.

[0031] The mechanochemical treatment area includes the ball mill equipment body, ball mill tank, automatic loading and unloading system and control unit. The ball mill tank is detachable and replaceable. The control unit controls the automatic loading and unloading system to realize the loading and unloading of the ball mill tank. The feeding and loading of the processing area of ​​the entire production line are all controlled by the control unit, which can realize fully automated processing.

[0032] The main body of the ball mill is fixed and located above the feed production line. It can be set horizontally or vertically according to the factory space and production needs. The ball mill tank is detachable and replaceable, and the control unit controls the automatic loading and unloading system to realize the loading and unloading operation of the ball mill tank.

[0033] When feeding, the control unit controls the automatic loading and unloading system to load the ball mill tank, the main body of the ball mill equipment enters the working state, and the ball milling begins; when unloading, the ball milling is completed, the control unit controls the automatic loading and unloading system to unload the ball mill tank, and the main body of the ball mill equipment enters the standby state.

[0034] The automatic loading and unloading system is a mechanical arm that assists in automated production. Its main function is to load the cans to be ball milled and unload the cans after ball milling. The control unit is the control center of the entire system. It determines the loading area of ​​the cans and controls the unloading of the cans after ball milling according to the working or standby status of each processing area. The automatic loading and unloading system is controlled by the control unit to achieve automated operation.

[0035] In some embodiments, the control unit simultaneously controls the ball milling conditions, including ball milling intensity, ball milling time, ball milling direction, ball milling interval, etc.

[0036] In some embodiments, the ball milling time is 0.5-2 h, and the ball milling speed is 200-1000 rpm, wherein the ball milling time is the time excluding the ball milling interval, that is, the ball milling time does not include the ball milling interval time.

[0037] The leaching unit is arranged downstream of the continuous mechanochemical unit, and the leaching unit performs solid-liquid separation on the material processed by the continuous mechanochemical unit to extract and separate lithium.

[0038] In some embodiments, the leaching unit adopts a water leaching process, and the leaching unit uses a water leaching process to separate the solid and liquid of the material after the mechanochemical treatment, separates and extracts the lithium into a lithium-containing leaching solution, and only extracts valuable metals. The mechanochemical extraction rate is high, and the waste after extraction does not need to be subjected to secondary extraction treatment.

[0039] Compared with the traditional mechanochemical process, the system of the present invention can realize industrialized continuous production, greatly increase the production scale and production efficiency, and achieve an industrial breakthrough in the mechanochemical extraction of lithium from retired lithium batteries, which is suitable for the treatment of retired lithium iron phosphate batteries. At the same time, compared with the drum-type mechanochemical technology, the present invention is more applicable to the resource treatment of retired lithium batteries, has a stronger mechanical grinding effect, the grinding material is finer, the uniformity is better, the grinding efficiency is greatly improved, the grinding time is greatly reduced, and the requirements for crushing pretreatment are lower.

[0040] like Figure 4 As shown, the working method of the continuous mechanochemical industrial lithium extraction system for retired lithium batteries, using the system of the present invention, includes the following steps: (a) Disassembling the retired battery pack to obtain the positive electrode sheet; (b) crushing the positive electrode sheet to obtain positive electrode crushed material; (c) packaging the positive electrode crushed material and the grinding aid into the ball mill tank; (d) The ball mill is placed on the machine, and after the ball milling is completed, lithium is extracted using a water leaching process.

[0041] Among them, in step (a), the disassembly unit disassembles the battery pack step by step, disassembles the battery pack to obtain the module, and then disassembles the module to obtain the battery cell, and finally from the battery cell to the positive electrode sheet. In step (b), the crushing unit relies on the crusher to crush the positive electrode sheet, reduce the material particle size, and obtain the crushed positive electrode sheet material. In step (c), the loading unit encapsulates the positive electrode crushed material and the grinding aid into the ball mill tank body for subsequent continuous mechanochemical unit loading. In step (d), the continuous mechanochemical unit includes multiple parallel lines, and multiple parallel production lines realize the planned treatment of retired lithium batteries. Each production line includes a feeding production line, a discharging production line and multiple mechanochemical processing areas. When feeding, the control unit controls the automatic loading and unloading system to load the ball mill tank body, the ball mill equipment body enters the working state, and the ball milling starts; when unloading, the ball milling is completed, the control unit controls the automatic loading and unloading system to unload the ball mill tank body, and the ball mill equipment body enters the standby state. After the ball milling is completed, the leaching unit uses a water leaching process to separate the solid and liquid of the material after the mechanochemical treatment, and separates and extracts the lithium.

[0042] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms may be for different embodiments or examples. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, unless they are contradictory.

[0043] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0044] Although the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A continuous mechanochemical industrial lithium extraction system for retired lithium batteries, characterized in that: include: A disassembly unit, wherein the disassembly unit disassembles the battery pack step by step to obtain the positive electrode sheet; A crushing unit is provided downstream of the disassembling unit, and the crushing unit crushes the positive electrode sheet to obtain positive electrode crushed material; A loading unit is arranged downstream of the crushing unit, and the loading unit packages the positive electrode crushed material and the grinding aid into a ball mill tank; A continuous mechanochemical unit is arranged downstream of the loading unit, the continuous mechanochemical unit includes a plurality of parallel production lines, each of which includes a feeding production line, a discharging production line and a plurality of mechanochemical treatment zones, the plurality of mechanochemical treatment zones are arranged in series on the upper part of the feeding production line, the mechanochemical treatment zone includes a ball milling equipment body, a ball milling tank body, an automatic loading and unloading system and a control unit, the ball milling tank body is detachable and replaceable, and the control unit controls the automatic loading and unloading system to realize the loading and unloading operation of the ball milling tank body; The leaching unit is arranged downstream of the continuous mechanochemical unit, and the leaching unit performs solid-liquid separation on the material processed by the continuous mechanochemical unit to extract and separate lithium.

2. The system according to claim 1, characterized in that The disassembly process of the disassembly unit includes appearance and leakage detection - removing the upper cover and battery pack to discharge - removing the copper bus and wiring harness - removing the BMS and electronic accessories - removing the module fixing screws - removing the module upper cover and circuit board - module discharge - milling the bus and end side plates - disassembling the module - disassembling the battery cell - removing the positive electrode sheet.

3. The system according to claim 1, characterized in that The grinding aid includes one or more of an acidic leaching agent, an oxidizing agent, and an inorganic salt.

4. The system according to claim 1, characterized in that When feeding, the ball mill tank body is put on the machine, the ball mill equipment body enters the working state, and ball milling begins; when unloading, the ball milling is completed, the ball mill tank body is unloaded, and the ball mill equipment body enters the standby state.

5. The system according to claim 4, characterized in that During ball milling, the ball milling time is 0.5-2h, and the rotation speed of the ball mill is 200-1000rpm.

6. The system according to claim 1, wherein: The ball milling equipment body is horizontal or vertical.

7. The system according to claim 1, characterized in that The automatic loading and unloading system is a robotic arm.

8. The system of claim 1, wherein: The leaching unit adopts a water leaching process.

9. A working method of a continuous mechanochemical industrial lithium extraction system for retired lithium batteries, characterized in that: Using the system described in any one of claims 1 to 8, comprising the following steps: (a) Disassembling the retired battery pack to obtain the positive electrode sheet; (b) crushing the positive electrode sheet to obtain positive electrode crushed material; (c) packaging the positive electrode crushed material and the grinding aid into a ball mill tank; (d) The ball mill is placed on the machine, and after the ball milling is completed, lithium is extracted using a water leaching process.

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