Waste battery recycling method

Abstract

The present application provides a waste battery recycling method and apparatus. In the method, a low-melting-point molten salt having reducing properties is used as a reactant to separate elements such as Li, Co, Ni, and Mn from oxygen in waste batteries, so as to generate chloride salts which facilitate subsequent reactions, and by means of the subsequent reactions, elements such as Li, Co, Ni, and M in waste batteries can be extracted step by step, thereby simplifying the recycling process. The waste battery recycling method of the present application has the advantages of low cost, high recycling yield, and low requirements for the recycling device.

Description

A method for recycling used batteries

[0001] This application claims priority to Chinese Patent Application No. 2024118722294, filed on December 18, 2024, entitled "A Method and Apparatus for Recycling Waste Batteries", and Chinese Patent Application No. 2024118773135, filed on December 18, 2024, entitled "A Method and Apparatus for Recycling Waste Batteries", the entire contents of which are incorporated herein by reference. Technical Field

[0002] This application relates to the field of battery recycling technology, and in particular to a method and apparatus for recycling waste batteries. Background Technology

[0003] In recent years, under the backdrop of carbon neutrality, new energy has developed rapidly. The demand and usage of batteries in areas related to the large-scale development and application of new energy, such as grid energy storage and electric vehicles, have remained high, resulting in a year-on-year increase in waste batteries. According to Guosheng Securities' calculations, from 2019 to 2025, the total amount of retired power batteries in China alone is expected to rise from 0.2 GWh to 52.0 GWh. Faced with a large and increasing number of waste batteries, developing efficient and environmentally friendly battery recycling technologies is crucial. Waste battery recycling not only aligns with the development direction of pollution reduction and carbon reduction, but also, because waste batteries are rich in high-value metal elements such as nickel, cobalt, and / or lithium, recycling them holds enormous economic value and is vital for alleviating battery-related resource shortages and promoting the sustainable development of the battery industry.

[0004] Battery recycling can be divided into two main stages: secondary utilization and resource regeneration. Currently, recycling has two relatively mature process routes: pyrometallurgical recycling and hydrometallurgical recycling. Secondary utilization mainly targets lithium iron phosphate, but the current evaluation process is time-consuming and inefficient. Resource regeneration has higher recycling efficiency and a shorter cycle, but hydrometallurgical recycling has problems such as large consumption of acids and alkalis, large consumption of fresh water, generation of wastewater and waste salts and other pollutants, and low lithium recovery rate; pyrometallurgical recycling has problems such as high energy consumption and difficulty in recovering lithium and sodium.

[0005] Molten salt electrolysis involves mixing spent batteries with molten salt and electrolyzing to extract non-lithium active metal elements. For example, lithium cobalt oxide powder is sintered to form a cathode, and Co or CoO powder is prepared by electrolysis using carbonate as the molten salt. Li₂CO₃ is then obtained through dissolution and filtration. However, this method is limited to lithium cobalt oxide batteries, and the molten salt is not recovered, thus failing to achieve resource recycling. Another method involves mixing lithium cobalt oxide powder with cobalt chloride and adding it to a molten salt containing lithium chloride. After electrolysis, water leaching, and filtration, cobalt powder is obtained. The filtrate can be crystallized to obtain lithium chloride. However, the melting temperature of the molten salt is as high as 605℃, and the electrolysis temperature is as high as 650℃~750℃, with a low final product recovery rate. Yet another method uses glass oxide melt to dissolve transition metal oxides, and Na₂O or NaF is added to the molten salt. The oxides are then reduced to the cathode through electrolytic reduction. This method reaches a molten salt temperature of 600℃~1000℃, and additional Na₂O or NaF additives are required to recover the transition metal oxides from spent batteries.

[0006] This shows that the recycling and reuse of high-value metal elements in waste batteries is very important for promoting the sustainable development of the battery industry and the new energy industry, but it still faces many challenges.

[0007] In the field of chlorination metallurgy, traditional chlorination has proven to be an effective method for processing low-grade, complex-component minerals. While this method can yield high-purity products, it requires high reaction temperatures and sophisticated equipment. Therefore, developing a low-temperature, low-cost, and high-recovery method for extracting high-value metal elements from spent batteries is crucial. Summary of the Invention

[0008] The purpose of this application is to provide a method and apparatus for recycling waste batteries, which reduces recycling costs, increases recycling yield, lowers the recycling reaction temperature, and thus reduces the requirements for the recycling equipment. Furthermore, it can handle a wider variety of waste batteries and allows for the recovery of molten salt. The specific technical solution is as follows:

[0009] The first aspect of this application provides a method for recycling used batteries, comprising the following steps:

[0010] Pretreatment: The waste battery cathode material is pretreated to obtain a solid mixture; the solid mixture includes a first metal element, which is a non-lithium active metal element selected from at least one of nickel, cobalt, and manganese;

[0011] Obtaining a molten salt bath: A solid mixture is mixed with molten salt to obtain a molten salt bath;

[0012] First impurity removal stage: Remove impurity a; the metallic activity of impurity a is lower than that of either nickel or cobalt.

[0013] Non-lithium active metal element extraction stage: extraction of nickel and / or cobalt;

[0014] Second impurity removal stage: Remove impurity b; or, remove impurity b and extract metallic manganese; the metallic activity of impurity b is higher than that of either nickel or cobalt.

[0015] In the pretreatment stage or the molten salt bath stage, chlorination or sulfidation reactions are carried out.

[0016] In some embodiments of this application, a method for recycling used batteries includes the following steps:

[0017] S100, Pretreatment: Pretreatment of waste battery cathode material to obtain solid mixture;

[0018] The solid mixture contains a first metal element and a second metal element, wherein the second metal element is selected from either lithium or sodium, and the first metal element is a non-lithium active metal element, wherein the non-lithium active metal element is selected from at least one of nickel, cobalt, and manganese.

[0019] S200, Chlorination reaction: The solid mixture is mixed with molten salt to carry out a chlorination reaction, resulting in a molten salt bath. The molten salt contains AlCl4. - Compounds;

[0020] S300, First impurity removal stage: The molten salt bath is subjected to a first displacement reaction with the first active metal plate. After precipitation, impurity a and the first melt are obtained, wherein the metal activity of impurity a is lower than that of either nickel or cobalt.

[0021] S400, Non-lithium active metal element extraction stage: The first melt is subjected to a second displacement reaction with the second active metal plate. After precipitation, metallic nickel and / or metallic cobalt are extracted, and the second melt is obtained.

[0022] S500, Second impurity removal stage: The second melt is subjected to a third displacement reaction with the third active metal plate. After precipitation, impurity b and the third melt are obtained, or impurity b, the third melt and metallic manganese are obtained.

[0023] Among them, the metal activity of impurity b is higher than that of either nickel or cobalt.

[0024] S600, Second metal element extraction stage: Extracting the second metal element from the third melt.

[0025] This application utilizes molten salt to chemically separate metal elements such as Li, Co, Ni, and Mn from oxygen in waste batteries, and then combines them with chlorine to form chloride salts. This reduces the difficulty of subsequent extraction processes. Simultaneously, the molten salt provides a suitable reaction medium, allowing the reaction to proceed more fully. Furthermore, the lower reaction temperature of the molten salt system reduces the requirements for the recycling equipment. This method for extracting high-value metal elements from waste batteries reduces costs and the required recycling reaction temperature while increasing yield.

[0026] In some embodiments of this application, the molten salt is selected from at least one of NaAlCl4, LiAlCl4, and KAlCl4.

[0027] In some embodiments of this application, the mass ratio of the solid mixture to the molten salt is 1:3 to 1:20; preferably, the mass ratio of the solid mixture to the molten salt is 1:5 to 1:10.

[0028] In some embodiments of this application, the chlorination reaction includes: NMO2 + QAlCl4 = QAlO2 + NCl + MCl2 + 1 / 2Cl2

[0029] N is selected from at least one of Li and Na; M is selected from at least one of Co, Mn and Ni; and Q is selected from at least one of Li, K and Na.

[0030] In some embodiments of this application, the reaction temperature T2 of the chlorination reaction is 200°C to 800°C, and preferably, the reaction temperature T2 of the chlorination reaction is 350°C to 550°C.

[0031] In some embodiments of this application, in step S300, the first impurity removal stage, the material of the first active metal plate is selected from any one of cobalt and nickel or their alloys; the reaction temperature T3 of the first displacement reaction is 300℃~400℃, and the reaction time t3 is 1h~10h.

[0032] In some embodiments of this application, in step S400, the non-lithium active metal element extraction stage, the material of the second active metal plate is selected from any one of zinc and manganese or their alloys; the reaction temperature T4 of the second displacement reaction is 300℃~400℃, and the reaction time t4 is 1h~5h.

[0033] In some embodiments of this application, in step S500, the second impurity removal stage, the material of the third active metal plate is selected from aluminum metal; the reaction temperature T5 of the third displacement reaction is 300℃~400℃, and the reaction time t5 is 2h~10h.

[0034] In some embodiments of this application, the second metal element is selected from lithium, the molten salt is LiAlCl4, and the S600 extraction stage of the second metal element includes: splitting the third melt, extracting lithium from one part, and returning the other part to the molten salt after impurity removal; wherein, the lithium extraction includes: directly performing a rectification treatment A on the split part of the third melt to extract Li; or, performing an extraction treatment on the split part of the third melt first, and then performing a rectification treatment B to extract Li.

[0035] In some embodiments of this application, the second metal element is selected from lithium, and the molten salt includes LiAlCl4, as well as at least one of NaAlCl4 and KAlCl4; the S600 extraction stage of the second metal element includes: splitting the third molten liquid, extracting lithium from a portion of it, and returning the other portion to the molten salt after impurity removal; wherein, the lithium extraction includes: first extracting a portion of the split third molten liquid, and then performing a distillation process B to extract the Li element.

[0036] In some embodiments of this application, the second metal element is selected from lithium, and the molten salt is at least one of NaAlCl4 and KAlCl4. The S600 extraction stage of the second metal element includes: extracting lithium from all of the third melt; wherein, the lithium extraction includes: first extracting the third melt, and then distilling the resulting extract to extract Li.

[0037] In some embodiments of this application, the second metal element is selected from sodium, and the molten salt is selected from NaAlCl4. The S600 extraction stage of the second metal element includes: splitting the third molten liquid, extracting sodium from one part, and returning the other part to the molten salt after removing impurities; wherein, the sodium extraction includes: directly distilling a portion of the split third molten liquid to extract Na.

[0038] In some embodiments of this application, impurity a includes Cu; impurity b includes Zn.

[0039] In some embodiments of this application, distillation process A includes heating the third melt at a temperature T6, where T6 is 480°C to 550°C, to evaporate the flux AlCl3 in the third melt and obtain a solid second metal chloride.

[0040] In some embodiments of this application, the extraction process includes: cooling the third melt and crushing it into powder, dissolving the LiCl in the powder using an extractant to obtain an extract, wherein the extractant includes at least one of acetone, cyclohexanone, methanol, ethanol, isopropanol, and diethyl ether; the distillation process B includes: heating the extract at a temperature T6', where T6' is 60°C to 200°C, to evaporate the extractant in the extract to obtain LiCl.

[0041] The second aspect of this application provides a waste battery recycling device that can separate impurity elements, non-lithium active metal elements Ni / Co / Mn and Li / Na elements from the positive electrode material of waste batteries in steps, simplifying the impurity removal process and enabling the reuse of molten salt, thereby reducing costs.

[0042] This application also provides a waste battery recycling device, including a pretreatment device, a melting device, a first impurity removal device, a non-lithium active metal element extraction device, a second impurity removal device, and a second metal element extraction device; the pretreatment device includes a first inlet and a first outlet, the melting device includes a second inlet and a second outlet, the first impurity removal device includes a third inlet and a third outlet, the non-lithium active metal element extraction device includes a fourth inlet and a fourth outlet, and the second impurity removal device includes a fifth inlet and a fifth outlet; the first outlet is connected to the second inlet; the second outlet is connected to the third inlet; the third outlet is connected to the fourth inlet; the fourth outlet is connected to the fifth inlet; and the fifth outlet is connected to the second metal element extraction device, wherein the melting device is used to perform the chlorination reaction.

[0043] In some embodiments of this application, the pretreatment device further includes a pretreatment chamber, a magnetic separation crusher and mixer, a first heating and insulation layer, and a screen; the melting device further includes a melting chamber, a stirrer, a feeding and return port, and a second heating and insulation layer; the first impurity removal device further includes a first displacement impurity removal chamber, a first active metal plate, a first precipitation outlet, a first precipitation receiving tank, and a third heating and insulation layer; the non-lithium active metal element extraction device further includes a non-lithium active metal element displacement extraction chamber, a second active metal plate, a second precipitation outlet, a second precipitation receiving tank, and a fourth heating and insulation layer; the second impurity removal device further includes a second displacement impurity removal chamber, a third active metal plate, a third precipitation outlet, a third precipitation receiving tank, and a fifth heating and insulation layer.

[0044] In some embodiments of this application, the second metal element extraction device includes an extraction extractor, a distillation extractor B, and a first dust collector connected sequentially in a direction away from the second impurity removal device; the extraction extractor includes a sixth feed inlet, a sixth discharge outlet, a powder discharge outlet, a sixth heating and insulation layer, a dryer, a solvent vapor pipeline, a vapor reflux and replenishment inlet, and an extraction chamber; the distillation extractor B includes a seventh feed inlet, a seventh discharge outlet, a first product outlet, a first product collection tank, a seventh heating and insulation layer, and a first distillation chamber; the first dust collector includes a first vapor inlet, a first vapor outlet, a first dust collection outlet, a first dust collection filter, a first fine powder collection tank, and a first dust collection chamber.

[0045] In some embodiments of this application, the second metal element extraction device includes a distillation extractor A and a second dust collector connected sequentially in a direction away from the second impurity removal device; the distillation extractor A includes an eighth feed inlet, an eighth discharge outlet, a second product outlet, a second product collection tank, an eighth heating and insulation layer, and a second distillation chamber; the second dust collector includes a second steam inlet, a second steam outlet, a second dust filter, a second dust outlet, a second fine powder collection tank, and a second dust collection chamber.

[0046] In some embodiments of this application, the second metal element extraction device further includes a diversion pipeline and a diversion valve; one end of the diversion pipeline and the diversion valve are located between the fifth discharge port and the sixth inlet port; or, one end of the diversion pipeline and the diversion valve are located between the fifth discharge port and the eighth inlet port.

[0047] In some embodiments of this application, the waste battery recycling device further includes a purification device and a reflux device connected sequentially in a direction away from the second metal element extraction device. The purification device is connected to the second metal element extraction device. The reflux device is connected to the purification device and the melting device and is used to return molten salt to the melting device.

[0048] In some embodiments of this application, the height of the first discharge port is higher than the height of the second inlet port; the height of the second discharge port is higher than the height of the third inlet port; the height of the third discharge port is higher than the height of the fourth inlet port; the height of the fourth discharge port is higher than the height of the fifth inlet port; and the height of the fifth discharge port is higher than the height of the sixth inlet port or higher than the height of the eighth inlet port.

[0049] In some embodiments of this application, the waste battery recycling device is used in the waste battery recycling method described in any of the above embodiments.

[0050] This application provides a method and apparatus for recycling waste batteries. The method uses molten salt as a reactant in a molten salt bath system to separate elements such as Li, Co, Ni, and Mn from oxygen in waste batteries and combine them with chlorine to form chloride salts, which are easier to react in subsequent displacement reactions, thus reducing the difficulty of the subsequent displacement extraction process. Specifically, on the one hand, it reduces the temperature requirements and the requirements for the displacement metal plate in the displacement process. On the other hand, in the molten salt system, the pretreated solid mixture is in the solid phase, and the molten salt is in the liquid phase. This solid-liquid contact allows the chlorination reaction to proceed more thoroughly, reducing chloride loss. Moreover, the chloride salts converted from Li, Co, Ni, and Mn can dissolve in the molten salt system, forming a solid-liquid reaction interface with the displacement metal plate. This molten salt system also allows the subsequent displacement reaction to proceed more fully. Furthermore, the reaction temperature of the molten salt system is relatively low, and the temperature required for the chlorination reaction is also low. The subsequent chloride salts can also complete the displacement reaction with the metal plate at a lower temperature. Therefore, the equipment requirements for the chlorination and displacement reactions are lower, making it energy-saving, environmentally friendly, and more conducive to industrial production. Furthermore, lithium chloride or sodium chloride can be obtained subsequently through direct distillation or extraction followed by distillation, allowing for the reuse of residual molten salt, thus reducing raw material costs and the difficulty of impurity removal. Compared to traditional metal element recovery processes, this process does not require the use of acids and alkalis, significantly reducing wastewater and waste salt emissions, and offers advantages such as low cost, low consumption, high yield, and strong environmental friendliness. Of course, implementing any product or method of this application does not necessarily require achieving all of the above-mentioned advantages simultaneously.

[0051] In some embodiments of this application, a method for recycling waste batteries is also provided, comprising the following steps:

[0052] S100, Pretreatment: The waste battery cathode material is pretreated to obtain a solid mixture. The pretreatment includes pretreatment chlorination or pretreatment sulfidation. The solid mixture includes a first metal element, which is a non-lithium active metal element selected from at least one of nickel, cobalt, and manganese.

[0053] The pretreatment chlorination includes: mixing the positive electrode material with at least a chlorinating agent to carry out a chlorination reaction to obtain the solid mixture, wherein the solid mixture includes a chloride of a first metal element;

[0054] The pretreatment sulfidation includes: mixing the cathode material with at least a sulfur source to carry out a sulfation reaction to obtain the solid mixture, wherein the solid mixture includes the sulfate of a first metal element;

[0055] S200, Obtaining a molten salt bath system: The solid mixture is mixed with molten salt, and after melting, a molten salt bath is formed;

[0056] S300, First impurity removal stage: Remove impurity a; the metal activity of impurity a is lower than that of either nickel or cobalt.

[0057] S400, Non-lithium Active Metal Element Extraction Stage: Extraction of Nickel and / or Cobalt;

[0058] S500, Second impurity removal stage: Remove impurity b; or, remove impurity b and extract metallic manganese;

[0059] The metal activity of impurity b is higher than that of either nickel or cobalt.

[0060] This application first converts Li, Co, Ni, Mn, and other metallic elements in waste batteries into metal salts that are easier to extract later through pretreatment chlorination or pretreatment sulfidation. The metal salts are then mixed with molten salt to form a molten salt bath, allowing for direct electrolysis or displacement reactions. This reduces the introduction of impurities, improves the yield and purity of the metal elements, and the molten salt system operates at a lower reaction temperature. Furthermore, completing the chlorination or sulfidation of the metal elements during the pretreatment stage allows for a wider variety of molten salts that can be used in the subsequent molten salt bath to meet different environmental requirements. This method for extracting high-value metal elements from waste batteries reduces costs and increases yield.

[0061] In some embodiments of this application, the chlorinating agent in the pretreatment chlorination is selected from at least one of Cl2, NH4Cl, and HCl.

[0062] In some embodiments of this application, the positive electrode material is mixed with a chlorinating agent to undergo a chlorination reaction to obtain the solid mixture, including: mixing the positive electrode material with a chlorinating agent to undergo a chlorination reaction to obtain the solid mixture; preferably, the molar amount of the first metal element in the positive electrode material is n1, the molar amount of the second metal element is n2, and the molar amount of Cl element in the chlorinating agent is n3, satisfying n3≥2n1+n2, where n1>0 and n2≥0.

[0063] In some embodiments of this application, the positive electrode material is mixed with a chlorinating agent to undergo a chlorination reaction to obtain the solid mixture, including: mixing the positive electrode material with a chlorinating agent and a first reducing agent to undergo a chlorination reaction to obtain the solid mixture; wherein, the first reducing agent is selected from at least one of coke, coal powder, NH4Cl, HCl, and CO; preferably, the molar amount of the first metal element in the positive electrode material is n1, the molar amount of the second metal element is n2, the molar amount of Cl element in the chlorinating agent is n3, and the molar amount of Cl element in the first reducing agent is n4, satisfying n3+n4≥2n1+n2, where n1>0, n2≥0, and n4≥0.

[0064] In some embodiments of this application, the positive electrode material is mixed with a chlorinating agent to undergo a chlorination reaction to obtain the solid mixture, including: mixing the positive electrode material with a chlorinating agent, a first reducing agent, and a first oxidizing agent to undergo a chlorination reaction to obtain the solid mixture; wherein, the first reducing agent is selected from at least one of coke, coal powder, NH4Cl, HCl, and CO; the first oxidizing agent is selected from at least one of O2, O3, and MnO2; preferably, the molar amount of the first metal element in the positive electrode material is n1, the molar amount of the second metal element is n2, the molar amount of Cl element in the chlorinating agent is n3, and the molar amount of Cl element in the first reducing agent is n4, satisfying n3+n4≥2n1+n2, wherein n1>0, n2≥0, and n4≥0.

[0065] In some embodiments of this application, the conditions for the chlorination reaction include: a temperature T1 of 300°C to 900°C and a time t1 of 0.1h to 10h.

[0066] In some embodiments of this application, the sulfur source in the pretreatment sulfidation is selected from at least one of (NH4)2SO4, SO2, and H2SO4.

[0067] In some embodiments of this application, the solid mixture is obtained by mixing the cathode material with a sulfur source at least and performing a sulfation reaction. This includes: mixing the cathode material with a sulfur source and performing a sulfation reaction to obtain the solid mixture; preferably, the molar amount of the first metal element in the cathode material is n1, the molar amount of the second metal element is n2, and the molar amount of S element in the sulfur source is n5, satisfying n5≥n1+0.5n2, where n1>0 and n2≥0.

[0068] In some embodiments of this application, the solid mixture is obtained by mixing the cathode material with at least a sulfur source and performing a sulfation reaction, including: mixing the cathode material with a sulfur source and a second reducing agent and performing a sulfation reaction to obtain the solid mixture; wherein the second reducing agent is selected from at least one of coke, pulverized coal, SO2, (NH4)2SO4, and CO; preferably, the molar amount of the first metal element in the cathode material is n1, the molar amount of the sulfur element in the sulfur source is n5, and the molar amount of the sulfur element in the second reducing agent is n6, satisfying n5+n6≥n1+0.5n2, wherein n1>0, n2≥0, and n6≥0.

[0069] In some embodiments of this application, the solid mixture is obtained by mixing the cathode material with at least a sulfur source and performing a sulfation reaction, including: mixing the cathode material with a sulfur source, a second reducing agent, and a second oxidizing agent and performing a sulfation reaction to obtain the solid mixture; wherein, the second reducing agent is selected from at least one of coke, pulverized coal, SO2, (NH4)2SO4, and CO; the second oxidizing agent is selected from at least one of O2, O3, and MnO2; preferably, the molar amount of the first metal element in the cathode material is n1, the molar amount of the second metal element is n2, the molar amount of S element in the sulfur source is n5, and the molar amount of S element in the second reducing agent is n6, satisfying n5+n6≥n1+0.5n2, wherein n1>0, n2≥0, and n6≥0.

[0070] In some embodiments of this application, the conditions for the sulfation reaction include: a temperature T1' of 300°C to 900°C and a time t1' of 0.1h to 10h.

[0071] In some embodiments of this application, in step S200, the melting temperature T2 is 200℃~800℃; preferably, the melting temperature T2 is 350℃~700℃; preferably, the mass ratio of the solid mixture to the molten salt is 1:3~1:20.

[0072] In some embodiments of this application, step S300, the first impurity removal stage includes: performing a first electrolysis on the molten salt bath, and after precipitation, obtaining impurity a and a first melt; step S400, the non-lithium active metal element extraction stage includes: performing a second electrolysis on the first solution, and after precipitation, extracting nickel and / or cobalt, and obtaining a second melt; step S500, the second impurity removal stage includes: performing a third electrolysis on the second melt, and after precipitation, obtaining impurity b and a third melt; or, obtaining impurity b, the third melt, and metallic manganese.

[0073] In some embodiments of this application, in step S300, the conditions for the first electrolysis include: the electrolysis voltage U1 is in the range of 0.5V≤U1≤1V, and the electrolysis temperature T3 is in the range of 350℃≤T3≤700℃; in step S400, the conditions for the second electrolysis include: the electrolysis voltage U2 is in the range of 1V<U2≤2.5V, and the electrolysis temperature T4 is in the range of 350℃≤T4≤700℃; in step S500, the conditions for the third electrolysis include: the electrolysis voltage U3 is in the range of 2.5V<U3≤3.5V, and the electrolysis temperature T5 is in the range of 350℃≤T5≤700℃.

[0074] In some embodiments of this application, the cathode and anode in the first electrolysis, second electrolysis, and third electrolysis are independently selected from any one of inert electrodes; the inert electrode includes one of nickel plate, copper plate, stainless steel plate, graphite plate, platinum plate, and silver plate.

[0075] In some embodiments of this application, electrolysis is used, and the molten salt is selected from at least one of LiCl, NaCl, KCl, AlCl3, ZnCl2, NaBr, KBr, Na2CO3, K2CO3, Na2SO4, and KNO3.

[0076] In some embodiments of this application, step S300, the first impurity removal stage includes: subjecting the molten salt bath to a first displacement reaction with a first active metal plate, and after precipitation, obtaining impurity a and a first melt; in step S400, the non-lithium active metal element extraction stage includes: subjecting the first melt to a second displacement reaction with a second active metal plate, and after precipitation, extracting nickel and / or cobalt, and obtaining a second melt; in step S500, the second impurity removal stage includes: subjecting the second melt to a third displacement reaction with a third active metal plate, and after precipitation, obtaining impurity b and a third melt; or, obtaining impurity b, the third melt, and metallic manganese.

[0077] In some embodiments of this application, in step S300, the material of the first active metal plate is selected from any one of cobalt and nickel or their alloys; the reaction temperature T3' of the first displacement reaction is 300℃~400℃, and the reaction time t3' is 1h~10h; in step S400, the material of the second active metal plate is selected from any one of zinc and manganese or their alloys; the reaction temperature T4' of the second displacement reaction is 300℃~400℃, and the reaction time t4' is 1h~5h; in step S500, the material of the third active metal plate is selected from aluminum or its alloys; the reaction temperature T5' of the third displacement reaction is 300℃~400℃, and the reaction time t5' is 2h~10h.

[0078] In some embodiments of this application, a substitution method is used, wherein the molten salt is selected from at least one of LiCl, NaCl, KCl, AlCl3, ZnCl2, NaBr, KBr, Na2CO3, K2CO3, Na2SO4, KNO3, NaAlCl4, LiAlCl4, and KAlCl4.

[0079] In some embodiments of this application, impurity a includes Cu; impurity b includes at least one of Zn and Al.

[0080] In some embodiments of this application, the solid mixture further includes a second metal element, which is selected from either lithium or sodium; the waste battery recycling method further includes the following steps: S600, extraction of the second metal element stage: extracting the second metal element from the third melt.

[0081] In some embodiments of this application, the extraction of the second metal element from the third melt includes any of the following methods: Method 1: directly distilling the third melt to extract the second metal element; Method 2: first extracting the third melt, and then distilling the resulting extract to extract the second metal element; Method 3: cooling and crystallizing the third melt to extract the second metal element.

[0082] In some embodiments of this application, the second metal element is selected from lithium, the molten salt is selected from molten salt that does not contain lithium, and the step S600 extraction stage of the second metal element includes: extracting lithium from all of the third melt; wherein, the lithium extraction includes: first extracting the third melt, and then distilling the obtained extract to extract Li.

[0083] In some embodiments of this application, the second metal element is selected from lithium, the molten salt includes LiCl and / or LiAlCl4, and optionally a molten salt that does not contain lithium. Step S600, the stage of extracting the second metal element, includes: splitting the third melt, extracting lithium from a portion of it, and returning the other portion to the molten salt after removing impurities; wherein, the lithium extraction includes: first extracting a portion of the split third melt, and then performing a distillation process B to extract Li.

[0084] In some embodiments of this application, the second metal element is selected from lithium, and the molten salt is LiAlCl4, or LiCl and LiAlCl4. The extraction stage of the second metal element in step S600 includes: splitting the third melt, extracting lithium from a portion, and returning the other portion to the molten salt after impurity removal; wherein, the lithium extraction includes: directly distilling a portion of the split third melt to extract Li.

[0085] In some embodiments of this application, the second metal element is selected from lithium, and the molten salt is KCl, or LiCl and KCl. Step S600, the extraction stage of the second metal element, includes: extracting lithium from all of the third melt; or, splitting the third melt, extracting lithium from a portion and returning the other portion to the molten salt after impurity removal. The lithium extraction includes: cooling and crystallizing the third melt to extract Li. In some examples, the molten salt is KCl, and all of the third melt is used for lithium extraction; the molten salt is LiCl and KCl, and the third melt is split, extracting lithium from a portion and returning the other portion to the molten salt after impurity removal.

[0086] In some embodiments of this application, the second metal element is selected from sodium, and the molten salt is NaAlCl4, or NaCl and NaAlCl4. Step S600, the stage of extracting the second metal element, includes: splitting the third molten liquid, extracting sodium from one part, and returning the other part to the molten salt after removing impurities; wherein, the extraction of sodium includes: directly distilling a portion of the split third molten liquid to extract Na.

[0087] In some embodiments of this application, the second metal element is selected from sodium, and the molten salt is KCl, or NaCl and KCl. Step S600, the extraction stage of the second metal element, includes: extracting sodium from all of the third molten liquid; or, splitting the third molten liquid, extracting sodium from a portion and returning the other portion to the molten salt after impurity removal. The sodium extraction includes: cooling and crystallizing the third molten liquid to extract Na. In some examples, the molten salt is KCl, and sodium is extracted from all of the third molten liquid; the molten salt is NaCl and KCl, and the third molten liquid is split, extracting sodium from a portion and returning the other portion to the molten salt after impurity removal.

[0088] In some embodiments of this application, the extraction process includes: cooling the third melt and crushing it into powder, dissolving the LiCl in the powder using an extractant to obtain the extract, wherein the extractant is selected from at least one of acetone, cyclohexanone, methanol, ethanol, isopropanol, and diethyl ether; the distillation process B includes: heating the extract at a temperature T6, where T6 is 60°C to 200°C, to evaporate the extractant in the extract to obtain LiCl.

[0089] In some embodiments of this application, the distillation process A includes: heating the third melt at a temperature T6', where T6' is 480°C to 550°C, to evaporate the AlCl3 in the third melt and obtain a solid second metal chloride.

[0090] In some embodiments of this application, the cooling crystallization includes: cooling the third melt to T6”, causing the second metal chloride in the third melt to precipitate, thereby obtaining a solid second metal chloride; wherein the second metal element is lithium, and T6” is 345℃~360℃; or the second metal element is sodium, and T6” is 420℃~500℃.

[0091] This application also provides a waste battery recycling device that can separate impurity elements, non-lithium active metal elements Ni / Co / Mn and Li / Na elements from the positive electrode material of waste batteries in steps, simplifying the impurity removal process and enabling the reuse of molten salt, thereby reducing costs.

[0092] In some embodiments of this application, the waste battery recycling device includes a pretreatment device, a melting device, a first impurity removal device, a non-lithium active metal element extraction device, and a second impurity removal device connected in sequence.

[0093] In some embodiments of this application, the pretreatment device includes a first feed inlet, a first discharge outlet, a pretreatment chamber, a magnetic separation crusher and mixer, a first heating and insulation layer, and a screen; the melting device includes a second feed inlet, a second discharge outlet, a melting chamber, a stirrer, a feeding and return inlet, and a second heating and insulation layer; the first impurity removal device includes a third feed inlet, a third discharge outlet, a first electrolytic impurity removal chamber, a first anode inert electrode plate, a first cathode inert electrode plate, a first precipitation collection tank, a first precipitation outlet, and a third heating and insulation layer; the non-lithium active metal element extraction device includes a fourth feed inlet and a fourth discharge outlet. The device comprises a non-lithium active metal element electrolytic extraction chamber, a second anode inert electrode plate, a second cathode inert electrode plate, a second precipitation collection tank, a second precipitation outlet, and a fourth heating and insulation layer; the second impurity removal device includes a fifth inlet, a fifth outlet, a second electrolytic impurity removal chamber, a third anode inert electrode plate, a third cathode inert electrode plate, a third precipitation collection tank, a third precipitation outlet, and a fifth heating and insulation layer; the first outlet is connected to the second inlet, the second outlet is connected to the third inlet, the third outlet is connected to the fourth inlet, and the fourth outlet is connected to the fifth inlet.

[0094] In other embodiments of this application, the pretreatment device includes a first inlet, a first outlet, a pretreatment chamber, a magnetic separation crusher and mixer, a first heating and insulation layer, and a screen; the melting device includes a second inlet, a second outlet, a melting chamber, a stirrer, a feeding and return inlet, and a second heating and insulation layer; the first impurity removal device includes a sixth inlet, a sixth outlet, a first displacement impurity removal chamber, a first active metal plate, a fourth precipitation outlet, a fourth precipitation collection tank, and a sixth heating and insulation layer; the non-lithium active metal element extraction device includes a seventh inlet. The first discharge port, the second discharge port, the third discharge port, the fourth discharge port, the fifth discharge port, the fifth discharge port, the seventh heating and insulation layer are connected to the seventh discharge port, the fifth discharge port, the sixth discharge port, the seventh discharge port, and the eighth heating and insulation layer. The second impurity removal device includes an eighth inlet, an eighth discharge port, a second discharge port, a third active metal plate, a sixth discharge port, a sixth discharge port, a sixth discharge port, and an eighth heating and insulation layer. The first discharge port is connected to the second inlet, the second discharge port is connected to the sixth inlet, the sixth discharge port is connected to the seventh inlet, and the seventh discharge port is connected to the eighth inlet.

[0095] In some embodiments of this application, the apparatus further includes a second metal element extraction device, which is connected to the second impurity removal device.

[0096] In some embodiments of this application, the second metal element extraction device includes a cooling crystallization device; the cooling crystallization device includes a ninth inlet, a ninth outlet, a cooling crystallization chamber, a sedimentation cone bottom, a sedimentation outlet, a sedimentation collection tank, and a ninth heating and insulation layer.

[0097] In some other embodiments of this application, the second metal element extraction device includes an extraction extractor, a distillation extractor B, and a first dust collector connected sequentially in the direction away from the second impurity removal device; the extraction extractor includes a tenth feed inlet, a tenth discharge outlet, a powder discharge outlet, a tenth heating and insulation layer, a dryer, a solvent vapor pipeline, a vapor reflux and replenishment inlet, and an extraction chamber; the distillation extractor B includes an eleventh feed inlet, an eleventh discharge outlet, a first product outlet, a first product collection tank, an eleventh heating and insulation layer, and a first distillation chamber; the first dust collector includes a first vapor inlet, a first vapor outlet, a first dust collection outlet, a first dust collection filter, a first fine powder collection tank, and a first dust collection chamber.

[0098] In some further embodiments of this application, the second metal element extraction device includes a distillation extractor A and a second dust collector connected sequentially in a direction away from the second impurity removal device; the distillation extractor A includes a twelfth feed inlet, a twelfth discharge outlet, a second product outlet, a second product collection tank, a twelfth heating and insulation layer, and a second distillation chamber; the second dust collector includes a second steam inlet, a second steam outlet, a second dust filter, a second dust outlet, a second fine powder collection tank, and a first dust collection chamber.

[0099] In some embodiments of this application, the second metal element extraction device further includes a diversion pipeline and a diversion valve; one end of the diversion pipeline and the diversion valve are located between the fifth discharge port and the ninth inlet port.

[0100] In some other embodiments of this application, the second metal element extraction device further includes a diversion pipeline and a diversion valve; one end of the diversion pipeline and the diversion valve are located between the fifth discharge port and the tenth inlet port; or, one end of the diversion pipeline and the diversion valve are located between the eighth discharge port and the tenth inlet port.

[0101] In some further embodiments of this application, the second metal element extraction device further includes a diversion pipeline and a diversion valve; one end of the diversion pipeline and the diversion valve are located between the eighth discharge port and the twelfth inlet port; or, one end of the diversion pipeline and the diversion valve are located between the fifth discharge port and the twelfth inlet port.

[0102] In some embodiments of this application, the waste battery recycling device further includes a purification device and a reflux device connected sequentially in a direction away from the second metal element extraction device. The purification device is connected to the second metal element extraction device. The reflux device is connected to the purification device and the melting device and is used to return molten salt to the melting device.

[0103] In some embodiments of this application, the waste battery recycling device is used in the waste battery recycling method described in any of the above embodiments.

[0104] This application provides a method and apparatus for recycling waste batteries. The method involves chlorination or sulfidation in the pretreatment stage to remove carbon, organic matter, and other waste materials from the positive electrode material of the waste batteries, while simultaneously forming metal salts of elements such as Li, Co, Ni, and Mn, resulting in a solid mixture. This solid mixture is then added to a molten salt bath, which provides the medium for electrolysis or displacement reactions to be carried out stepwise, extracting high-value metal elements. On one hand, this method reduces the introduction of impurities, improving the yield and purity of metal elements. On the other hand, the molten salt system allows for more complete subsequent electrolysis or displacement reactions, and the lower reaction temperature of the molten salt system reduces the equipment requirements for these reactions. Furthermore, the molten salt can be reused, making it energy-efficient and environmentally friendly, and more conducive to industrial production. Moreover, completing the chlorination or sulfidation of metal elements in the pretreatment stage allows for the wider variety of molten salts that can be used in the subsequent molten salt bath to meet different environmental requirements. Furthermore, compared to traditional methods for extracting metal elements, this method eliminates the need for acids and alkalis, significantly reducing wastewater and salt emissions. It offers advantages such as low cost, low consumption, high yield, and strong environmental friendliness. Of course, implementing any product or method of this application does not necessarily require achieving all of the advantages described above simultaneously. Attached Figure Description

[0105] The accompanying drawings, which are provided to further illustrate this application and form part of this application, illustrate exemplary embodiments of this application and are used to explain this application, but do not constitute an undue limitation of this application.

[0106] Figure 1 is a flowchart of a waste battery recycling method according to one embodiment of this application;

[0107] Figure 2a is a flowchart of the extraction of non-lithium active metal elements in a waste battery recycling method according to one embodiment of this application;

[0108] Figure 2b is a flowchart of lithium or sodium extraction in a waste battery recycling method according to one embodiment of this application;

[0109] Figure 3 is a flowchart of a method for extracting and recovering metal elements from waste batteries according to another embodiment of this application;

[0110] Figure 4 is a diagram of a waste battery recycling device according to one embodiment of this application;

[0111] Figure 5 is a diagram of a waste battery recycling device according to another embodiment of this application;

[0112] Figure 6 is a diagram of the waste battery recycling device of Comparative Example 1-1 of this application.

[0113] Figure 7a is a flowchart of a waste battery recycling method according to one embodiment of this application;

[0114] Figure 7b is a flowchart of a method for electrolytically extracting and recovering metal elements from waste batteries according to one embodiment of this application;

[0115] Figure 7c is a flowchart of a method for extracting and recovering metal elements from waste batteries according to one embodiment of this application;

[0116] Figure 8 is a flowchart of the pretreatment process in a waste battery recycling method according to one embodiment of this application;

[0117] Figure 9 is a flowchart of the extraction of non-lithium active metal elements in a waste battery recycling method according to one embodiment of this application;

[0118] Figure 10 is a flowchart of lithium or sodium extraction in a waste battery recycling method according to one embodiment of this application;

[0119] Figure 11 is a diagram of a waste battery recycling device according to one embodiment of this application;

[0120] Figure 12 is a diagram of a waste battery recycling device according to another embodiment of this application;

[0121] Figure 13 is a diagram of a waste battery recycling device according to another embodiment of this application;

[0122] Figure 14 is a diagram of a waste battery recycling device according to another embodiment of this application;

[0123] Figure 15 is a flowchart of the purification of non-lithium active metal elements in one embodiment of this application;

[0124] Figure 16 is a flowchart of the purification of impurities b, Mn, etc. in one embodiment of this application.

[0125] In the specific implementation, the reference numerals in Figures 1, 2a, 2b, and 3-6 are as follows: 110. Pretreatment device, 510. Pretreatment chamber, 511. First feed inlet, 512. Magnetic separation crushing mixer, 513. Screen, 514. First discharge outlet, 515. First heating and insulation layer; 120. Melting device, 520. Melting chamber, 521. Second feed inlet, 522. Agitator, 523. Feeding and return outlet, 524. Second discharge outlet, 525. Second heating and insulation layer; 530. First impurity removal device, 620. First replacement impurity removal chamber, 621. Third feed inlet, 622. First active metal plate, 623. Third discharge outlet, 624. First sedimentation outlet, 625. First sedimentation collection tank, 626. Third heating and insulation layer; 540. Non-lithium active metal element extraction device; 720. Non-lithium active metal element displacement extraction chamber; 721. Fourth feed inlet; 722. Second active metal plate; 723. Fourth discharge outlet; 724. Second precipitation outlet; 725. Second precipitation receiving tank; 726. Fourth heating and insulation layer; 550. Second impurity removal device; 820. Second displacement impurity removal chamber; 821. Fifth feed inlet; 822. Third active metal plate; 823. Fifth discharge outlet; 824. Third precipitation outlet; 825. Third precipitation receiving tank; 826. Fifth heating and insulation layer; 560. Second metal element extraction device; 938. Diversion valve; 939. Diversion pipeline; 930. Extraction device; 931. Sixth feed inlet; 932. Steam reflux and replenishment inlet; 933. Sixth discharge outlet; 934. Powder discharge outlet; 935. Sixth heating and insulation layer; 936. Dryer; 937. Solvent vapor pipeline; 930A. Extraction chamber; 940. Distillation extractor B; 941. Seventh feed inlet; 942. Seventh discharge outlet; 943. First product outlet; 944. First product collection tank; 945. Seventh heating and insulation layer; 946. First distillation chamber; 950. First dust collector; 951. First steam inlet; 952. First steam outlet; 953. First dust filter; 954. First dust outlet; 955. First fine powder collection tank; 956. First dust collection chamber; 910. Distillation extractor A; 911. Eighth feed inlet; 912. Eighth discharge outlet; 913. Second product outlet; 914. Second product collection tank; 915. Eighth heating and insulation layer; 916. Second distillation chamber; 920. Second dust collector; 921. Second steam inlet; 922. Second steam outlet; 923. Second dust collector filter; 924. Second dust collector outlet; 925. Second fine powder receiving tank; 926. Second dust collection chamber; 130. Purification device; 570. Third impurity removal chamber; 571. Ninth feed inlet; 572. Impurity removal system; 573. Ninth discharge outlet; 574. Ninth heating and insulation layer; 140. Reflux device; 580. Reflux pump set; 590. Reflux pipeline.

[0126] In the specific implementation, the reference numerals in Figures 7a, 7b, 7c, and 8-16 are as follows: 110. Pretreatment device; 510. Pretreatment chamber; 511. First feed inlet; 512. Magnetic separation crushing mixer; 513. Screen; 514. First discharge outlet; 515. First heating and insulation layer; 120. Melting device; 520. Melting chamber; 521. Second feed inlet; 522. Agitator; 523. Feeding and return outlet; 524. Second discharge outlet; 525. Second heating and insulation layer; 530. First impurity removal device; 610. First electrolytic impurity removal chamber; 611. Third feed inlet; 612. First anode inert electrode plate; 613. First cathode inert electrode plate; 614. Third discharge outlet; 615. First sedimentation outlet; 616. First sedimentation collection tank; 617. Third heating and insulation layer; 620. First displacement impurity removal chamber; 621. Sixth feed inlet; 622. First active metal plate; 623. Sixth discharge outlet; 624. Fourth sedimentation outlet; 625. Fourth sedimentation collection tank; 626. Sixth heating and insulation layer; 540. Non-lithium active metal element extraction device; 710. Non-lithium active metal element electrolytic extraction chamber; 711. Fourth feed inlet; 712. Second anode inert electrode plate; 713. Second cathode inert electrode plate; 714. Fourth discharge outlet; 715. Second precipitation outlet; 716. Second precipitation collection tank; 717. Fourth heating and insulation layer; 720. Non-lithium active metal element displacement extraction chamber; 721. Seventh feed inlet; 722. Second active metal plate; 723. Seventh discharge outlet; 724. Fifth precipitation outlet; 725. Fifth precipitation collection tank; 726. Seventh heating and insulation layer; 550. Second impurity removal device; 810. Second electrolytic impurity removal chamber; 811. Fifth feed inlet; 812. Third anode inert electrode plate; 813. Third cathode inert electrode plate; 814. Fifth discharge outlet; 815. Third precipitation outlet; 816. Third precipitation collection tank; 817. Fifth heating and insulation layer; 820. Second displacement impurity removal chamber; 821. Eighth feed inlet; 822. Third active metal plate; 823. Eighth discharge outlet; 824. Sixth precipitation outlet; 825. Sixth precipitation collection tank; 826. Eighth heating and insulation layer; 560. Second metal element extraction device; 938. Diversion valve; 939. Diversion pipeline; 960. Cooling crystallization device; 961. Ninth feed inlet; 962. Ninth discharge outlet; 963. Ninth heating and insulation layer; 964. Settling cone bottom; 965. 966. Settling outlet; 967. Settling collection tank; 930. Cooling crystallization chamber; 931. Extractor; 932. Tenth feed inlet; 933. Steam reflux and replenishment inlet; 934. Tenth discharge outlet; 935. Tenth heating and insulation layer; 936. Dryer; 937. Solvent vapor pipeline; 930A. Extraction chamber; 940. Distillation extractor B; 941. Eleventh feed inlet; 942.Eleventh discharge port, 943. First product outlet, 944. First product receiving tank, 945. Eleventh heating and insulation layer, 946. First distillation chamber; 950. First dust collector, 951. First steam inlet, 952. First steam outlet, 953. First dust filter, 954. First dust outlet, 955. First fine powder receiving tank, 956. First dust collection chamber; 910. Distillation extractor A, 911. Twelfth feed port, 912. Twelfth discharge port, 913. Second product outlet, 914. Second product receiving tank, 915. Twelfth heating and insulation layer, 916. Second distillation chamber; 920. Second dust collector, 921. Second steam inlet, 922. Second steam outlet, 923. Second dust filter, 924. Second dust outlet, 925. Second fine powder receiving tank, 926. Second dust collection chamber; 130. Purification device; 570. Third impurity removal chamber; 571. Thirteenth feed inlet; 572. Impurity removal system; 573. Thirteenth discharge outlet; 574. Thirteenth heating and insulation layer; 140. Reflux device; 580. Reflux pump set; 590. Reflux pipeline. Detailed Implementation

[0127] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided with reference to the accompanying drawings and embodiments. Obviously, the described embodiments are merely some embodiments of this application, and not all embodiments. All other embodiments obtained by those skilled in the art based on this application are within the scope of protection of this application.

[0128] The recovery and recycling of high-value metal elements from spent batteries is crucial for promoting the sustainable development of the battery industry and the new energy sector. However, traditional battery recycling methods, such as pyrometallurgical recovery, hydrometallurgical recovery, molten salt electrolysis, and traditional chlorination metallurgy, suffer from problems such as high costs due to large acid and alkali consumption, high levels of pollutants such as wastewater and waste salts, difficulty in recovering lithium, and low product recovery rates. Therefore, this application provides a battery recycling method and a battery recycling apparatus to reduce recycling costs, increase recycling yield, lower the recycling reaction temperature, and thus reduce the requirements for the recycling apparatus.

[0129] This application provides a method for recycling used batteries, which includes the following steps:

[0130] Pretreatment: The waste battery cathode material is pretreated to obtain a solid mixture; the solid mixture includes a first metal element, which is a non-lithium active metal element selected from at least one of nickel, cobalt, and manganese;

[0131] Obtaining a molten salt bath: A solid mixture is mixed with molten salt to obtain a molten salt bath;

[0132] First impurity removal stage: Remove impurity a; the metallic activity of impurity a is lower than that of either nickel or cobalt.

[0133] Non-lithium active metal element extraction stage: extraction of nickel and / or cobalt;

[0134] Second impurity removal stage: Remove impurity b; or, remove impurity b and extract metallic manganese; the metallic activity of impurity b is higher than that of either nickel or cobalt.

[0135] In the pretreatment stage or the molten salt bath stage, chlorination or sulfidation reactions are carried out.

[0136] In some embodiments of this application, a molten salt bath is obtained by mixing a solid mixture with a molten salt and carrying out a chlorination reaction to obtain a molten salt bath, wherein the molten salt contains AlCl4. - Compounds.

[0137] In some embodiments of this application, the first impurity removal stage involves a first displacement reaction between a molten salt bath and a first active metal plate. After precipitation, impurity a and a first molten liquid are obtained. The metal activity of impurity a is lower than that of either nickel or cobalt.

[0138] In some embodiments of this application, the non-lithium active metal element extraction stage involves: subjecting a first melt to a second displacement reaction with a second active metal plate; after precipitation, extracting metallic nickel and / or metallic cobalt, and obtaining a second melt.

[0139] In some embodiments of this application, the second impurity removal stage involves reacting the second melt with the third active metal plate in a third displacement reaction, resulting in precipitation, to obtain impurity b and the third melt, or impurity b, the third melt, and metallic manganese; the metallic activity of impurity b is higher than that of either nickel or cobalt.

[0140] In some embodiments of this application, a second metal element extraction stage is also included: extracting the second metal element from the third melt; the second metal element is selected from either lithium or sodium.

[0141] As shown in Figures 1 to 3, the first aspect of this application also provides a method for recycling waste batteries, which includes the following steps:

[0142] S100, Pretreatment: Pretreatment of waste battery cathode material to obtain solid mixture;

[0143] The solid mixture contains a first metallic element and a second metallic element, wherein the second metallic element is selected from either lithium or sodium, and the first metallic element is a non-lithium active metallic element, wherein the non-lithium active metallic element is selected from at least one of nickel, cobalt, and manganese.

[0144] S200, Chlorination reaction: A solid mixture is mixed with molten salt to carry out a chlorination reaction, resulting in a molten salt bath. The molten salt contains AlCl4. - Compounds;

[0145] S300, First impurity removal stage: The molten salt bath is subjected to a first displacement reaction with the first active metal plate. After precipitation, impurity a and the first melt are obtained. The metal activity of impurity a is lower than that of either nickel or cobalt.

[0146] S400, Non-lithium active metal element extraction stage: The first melt is subjected to a second displacement reaction with the second active metal plate. After precipitation, metallic nickel and / or metallic cobalt are extracted, and the second melt is obtained.

[0147] S500, Second impurity removal stage: The second melt is subjected to a third displacement reaction with the third active metal plate. After precipitation, impurity b and the third melt are obtained, or impurity b, the third melt and metallic manganese are obtained.

[0148] Among them, impurity b has higher metallic activity than either nickel or cobalt.

[0149] S600, Second Metal Element Extraction Stage: Extracting the second metal element from the third molten metal.

[0150] The method provided in this application has the advantages of low cost, low consumption, high yield, energy saving, and environmental protection. This method uses a low-melting-point molten salt and a solid mixture obtained from the pretreatment of waste battery cathode materials for a chlorination reaction. The molten salt acts not only as a reactant but also as a reaction medium, making the chlorination reaction more thorough and generating chloride salts that are easier to react with in subsequent displacement reactions. The generated chloride salts can also dissolve in the molten salt, which is beneficial for the subsequent displacement reactions to proceed more fully. This reduces the reaction temperature during the extraction process and the requirements for the displacement metal plates, lowers the recycling cost, and increases the recovery yield of high-value metals from batteries. Furthermore, compared with traditional metal element recycling processes, this method does not require the use of acids and alkalis, significantly reducing wastewater and waste salt emissions, thus saving energy and protecting the environment. This method lowers the reaction temperature during the recycling process and eliminates the need for acids and alkalis, further reducing the requirements for the recycling equipment.

[0151] In some implementation schemes, the pretreatment includes at least one of the following methods: grinding, magnetic separation, sieving, calcination at 300℃ to 1000℃ for 0.1h to 10h, and reaction with reagents. The reaction with reagents includes heating the waste battery cathode material with an oxidant at 100℃ to 1500℃ for 0.1h to 10h. The oxidant includes at least one of O2, O3, and MnO2, and the amount of oxidant used is 50wt% to 500wt% of the waste battery cathode material. Its function is to remove easily oxidized substances such as carbon and organic matter from the waste battery cathode material. Through the above pretreatment process, the metal elements in the waste battery cathode material can be transformed into a state that is easier to extract, such as smaller particle size and fewer impurities.

[0152] In some embodiments of this application, the molten salt is selected from at least one of NaAlCl4, LiAlCl4, and KAlCl4. This molten salt serves both as a molten salt medium and as a chlorine source for reaction with the solid mixture, allowing for the formation of a chlorinated molten salt bath in a single step, simplifying the recovery process and reducing recovery costs.

[0153] In some embodiments of this application, the mass ratio of the solid mixture to the molten salt is 1:3 to 1:20; preferably, the mass ratio is 1:5 to 1:10. For example, the mass ratio of the solid mixture to the molten salt can be 1:3, 1:5, 1:7, 1:8, 1:10, 1:12, 1:14, 1:15, 1:17, or 1:20, or any two of the above numbers. By controlling the mass ratio of the solid mixture to the molten salt within the above range, the solid mixture and the molten salt can react fully, ensuring that all the metal elements to be recovered in the solid mixture are converted into chloride salts, thereby improving the recovery yield.

[0154] In some embodiments of this application, the chlorination reaction includes: NMO2 + QAlCl4 = QAlO2 + NCl + MCl2 + 1 / 2Cl2

[0155] N is selected from at least one of Li and Na; M is selected from at least one of Co, Mn, and Ni; and Q is selected from at least one of Li, K, and Na. The above-mentioned QAlCl4 exists as ionic AlCl4 in the molten salt state. - In the molten ionic state, the binding ability of Al and O elements is stronger than that of M (Co, Mn, Ni) elements with O elements. This allows M elements to be separated from oxides to form chlorides. At the same time, QAlCl4 can also provide a molten salt bath environment. The solid-liquid interface makes the chlorination reaction more complete and thorough. Moreover, the molten salt bath has a lower reaction system temperature, making it easier for subsequent non-lithium active metal elements to be displaced.

[0156] In some embodiments of this application, the reaction temperature T2 of the chlorination reaction is 200℃ to 800℃. For example, the reaction temperature of the chlorination reaction can be 200℃, 300℃, 400℃, 500℃, 600℃, 700℃, or 800℃, or any two of the above numbers. By controlling the reaction temperature of the chlorination reaction within the above range, not only can the molten salt be fully melted, providing a medium environment for the reaction between the molten salt and the solid mixture, but the chlorination reaction can also be carried out more completely, improving the recovery yield. Preferably, the reaction temperature T2 of the chlorination reaction is 350℃ to 550℃. Within this temperature range, not only can the molten salt be fully melted and the chlorination reaction be carried out more completely, but the reaction temperature and the requirements for equipment are also reduced. In some embodiments of this application, in the first impurity removal stage of step S300, the material of the first active metal plate is selected from any one of cobalt and nickel or their alloys; the reaction temperature T3 of the first displacement reaction is 300℃ to 400℃, and the reaction time t3 is 1h to 10h. For example, the reaction temperature of the first displacement reaction can be 300℃, 320℃, 350℃, 380℃, or 400℃, or any two of the above numbers. For example, the reaction time of the first displacement reaction can be 1h, 3h, 5h, 8h, or 10h, or any two of the above numbers. In some embodiments of this application, impurity 'a' includes Cu element, and impurity 'a' mainly originates from waste battery cathode materials. Through the above displacement reaction, impurity 'a' in the molten salt bath can be thoroughly removed. Using a metal plate with a higher reactivity than impurity 'a' but lower reactivity than or equal to that of non-lithium active metal elements, such as directly using a cobalt plate, can avoid introducing other impurities, allowing non-lithium active metal elements Co and / or Ni to be extracted during the non-lithium active metal element extraction stage. Removing impurity 'a' from the waste battery cathode material first facilitates the subsequent extraction of non-lithium active metal elements, improving the purity of the non-lithium active metal elements.

[0157] In some embodiments of this application, in step S400, the non-lithium active metal element extraction stage, the material of the second active metal plate is selected from any one of zinc and manganese or their alloys; the reaction temperature T4 of the second displacement reaction is 300℃~400℃, and the reaction time t4 is 1h~5h. For example, the reaction temperature of the second displacement reaction can be 300℃, 320℃, 350℃, 380℃ or 400℃, or any two of the above numbers. For example, the reaction time of the second displacement reaction can be 1h, 2h, 3h, 4h or 5h, or any two of the above numbers. Through the above displacement reaction, the non-lithium active metals nickel and / or cobalt in the molten salt bath can be fully displaced. Using a metal plate with a higher reactivity than Co and / or Ni, but a lower reactivity than or equal to impurity elements such as Zn, for example, directly using a Zn plate, avoids introducing more impurities. This allows Co and / or Ni to be displaced in the non-lithium active metal element extraction stage, while Zn is displaced in the second impurity removal stage.

[0158] In some embodiments of this application, in step S500, the second impurity removal stage, the material of the third active metal plate is selected from aluminum metal; the reaction temperature T5 of the third substitution reaction is 300℃~400℃, and the reaction time is 2h~10h. For example, the reaction temperature of the third substitution reaction can be 300℃, 320℃, 350℃, 380℃, or 400℃, or any two of the above numbers. For example, the reaction time of the third substitution reaction can be 2h, 3h, 5h, 7h, 9h, or 10h, or any two of the above numbers. In some embodiments of this application, impurity b includes Zn element. Impurity b mainly originates from waste battery cathode materials, or mainly from the active metal plate used in the second substitution reaction. The above-described displacement reaction effectively removes impurity b from the molten salt bath. If the cathode material of the spent batteries contains manganese, valuable manganese can also be extracted in this step. Using a metal plate, such as an Al plate, which is more reactive than impurity b and manganese but easily separated from Li or Na elements in subsequent lithium or sodium extraction stages, simplifies the recycling process, reduces costs, and increases the recycling yield. Removing impurity b from the molten salt bath facilitates the subsequent extraction of lithium or sodium elements, improving their purity.

[0159] By using the aforementioned first, second, and third active metal plates, non-lithium active metal elements, Li / Na elements, and impurity elements in the cathode material of spent batteries can be separated stepwise. Specifically, impurity elements with lower activity than Co / Ni are first replaced, then Co / Ni metal is removed, followed by the replacement of impurity elements with higher activity than Co / Ni and / or Mn elements, resulting in a lithium-rich melt (the third melt). This effectively recovers non-lithium active metal elements Ni / Co / Mn and Li / Na from spent batteries, simplifying the recycling process and avoiding the introduction of other impurities. By controlling the reaction temperature and time of the first, second, and third replacement reactions within the aforementioned range, impurity a, non-lithium active metal elements, and impurity b in the molten salt bath can be fully replaced, improving the recovery yield and purity of Ni / Co / Mn and Li / Na.

[0160] Of course, those skilled in the art can make appropriate selections for the first, second, and third active metal plates based on the teachings of this application and in conjunction with the type of impurity element to be removed.

[0161] In some implementations, the flow rate of the first displacement reaction is 40 g / h to 80 g / h, the flow rate of the second displacement reaction is 40 g / h to 80 g / h, and the flow rate of the third displacement reaction is 40 g / h to 80 g / h.

[0162] In this application, the reaction temperatures of the first displacement reaction, the second displacement reaction, and the third displacement reaction can be the same or different, as long as they can achieve the purpose of this application within the scope of this application.

[0163] In some embodiments of this application, the second metal element is selected from lithium, and the molten salt is LiAlCl4. The S600 extraction stage of the second metal element includes: splitting the third molten liquid, extracting lithium from one portion, and returning the other portion to the molten salt after impurity removal; wherein, lithium extraction includes: directly subjecting a portion of the split third molten liquid to distillation treatment A to extract Li element. In some embodiments of this application, distillation treatment A includes: heating the third molten liquid at a temperature T6, where T6 is 480℃~550℃, to evaporate the flux AlCl3 in the third molten liquid, obtaining a solid second metal chloride. For example, the heating temperature of distillation treatment A can be 480℃, 490℃, 500℃, 510℃, 530℃, 540℃, or 550℃, or any two of the above numbers. By heating the third molten liquid within the above temperature range, the molten salt LiAlCl4 can be decomposed into LiCl and AlCl3. AlCl3 will evaporate within this temperature range to obtain solid LiCl, realizing the recovery of Li element from waste battery cathode materials.

[0164] In some embodiments of this application, the second metal element is selected from lithium, and the molten salt is LiAlCl4; or, the molten salt includes LiAlCl4, and at least one of NaAlCl4 and KAlCl4, that is, the molten salt can be LiAlCl4 and NaAlCl4, or LiAlCl4 and KAlCl4, or LiAlCl4, NaAlCl4 and KAlCl4. Based on the above selection of the molten salt, the S600 stage for extracting the second metal element includes: splitting the third melt, extracting lithium from one part, and returning the other part to the molten salt after impurity removal; wherein, lithium extraction includes: first extracting the split portion of the third melt, and then performing distillation treatment B to extract the Li element. In some embodiments of this application, the extraction process includes: cooling and crushing the third melt into powder, dissolving the LiCl in the powder using an extractant to obtain an extract, wherein the extractant includes at least one selected from acetone, cyclohexanone, methanol, ethanol, isopropanol, and diethyl ether; the distillation process B includes: heating the extract at a temperature T6', where T6' is 60°C to 200°C, to evaporate the extractant in the extract and obtain LiCl. For example, the heating temperature of the extract can be 60°C, 80°C, 100°C, 120°C, 140°C, 150°C, 170°C, 190°C, or 200°C, or any two of the above numbers. By selecting a suitable extractant, the LiCl in the powder can be dissolved, and the distillation process B can evaporate the extractant in the LiCl to obtain solid LiCl, thereby improving the purity of LiCl.

[0165] There is no particular limitation on the flow rate of the third melt, as long as the Li element in the waste battery cathode material is extracted through the flow separation method, unnecessary energy consumption is avoided by heating the molten salt LiAlCl4, and the molten salt can be reused. In actual production, the amount of lithium extracted from the third melt can be adjusted according to actual needs, and the actual flow rate of the third melt can also be adjusted according to the actual amount of lithium extracted from the third melt. For example, based on the Li element content in the waste battery cathode material, the flow rate of the third melt before flow separation is M g / h, and the mass percentage of Li element in the cathode material is x%. After flow separation, the flow rate of the third melt used for lithium extraction can be greater than or equal to x% × M g / h, so that the amount of lithium extracted from the third melt is x% × M g / h, or the amount of lithium extracted from the third melt is equivalent to or greater than x% × M g / h, as long as the Li element in the waste battery cathode material can be extracted through the flow separation method. The remaining third melt is diverted and purified, and no further lithium extraction is performed. After purification, it is returned to the molten salt, thus achieving the reuse of the molten salt. When the amount of lithium extracted from the third melt is greater than x% × M g / h, it is actually a purification process of the molten salt, which is then returned to the molten salt for continued reuse.

[0166] For example, taking a lithium cobalt oxide battery as an example, the Li content in the positive electrode material of the lithium cobalt oxide battery is 6.45 wt%. Assuming that the flow rate of the third melt before diversion is 60 g / h, after diversion, the flow rate of the third melt used for lithium extraction should be greater than or equal to 3.87 g / h, so that the amount of lithium extracted from the third melt is 3.87 g / h, or the amount of lithium extracted from the third melt is equivalent to or greater than 3.87 g / h, as long as the Li element in the waste lithium cobalt oxide battery positive electrode material can be extracted by diversion.

[0167] In some embodiments of this application, the second metal element is selected from lithium, and the molten salt is at least one of NaAlCl4 and KAlCl4. The S600 extraction stage of the second metal element includes: extracting lithium from the entire third molten liquid; wherein, the lithium extraction includes: first extracting the third molten liquid, and then subjecting the resulting extract to distillation treatment B to extract Li element. NaAlCl4 in the molten salt bath decomposes into NaCl at high temperatures, and KAlCl4 decomposes into KCl at high temperatures. Therefore, direct distillation treatment A is not used; instead, the molten salt and LiCl can be separated through the above-mentioned extraction and distillation treatment B, and LiCl can also be separated from NaCl / KCl, thereby achieving the recovery of Li element from the molten salt bath.

[0168] In some embodiments of this application, the second metal element is selected from sodium, and the molten salt is selected from NaAlCl4. The S600 extraction stage for the second metal element includes: splitting the third molten liquid, extracting sodium from one portion, and returning the other portion to the molten salt after impurity removal; wherein, sodium extraction includes: directly subjecting a portion of the split third molten liquid to distillation treatment A to extract Na element. Through the above distillation treatment A, the molten salt NaAlCl4 can be decomposed into NaCl and AlCl3, and AlCl3 evaporates to obtain solid NaCl, thereby realizing the recovery of Na element from waste battery cathode materials.

[0169] The flow rate of the third melt is not specifically limited, as long as the Na element in the waste battery cathode material is extracted through diversion, avoiding energy consumption from heating the molten salt NaAlCl4 and enabling the reuse of the molten salt. In actual production, the amount of sodium extracted from the third melt can be adjusted according to actual needs, and the actual flow rate of the third melt can also be adjusted based on the actual amount of sodium extracted. For example, based on the Na content in the waste battery cathode material, the flow rate of the third melt before diversion is N g / h, and the mass percentage of Na in the cathode material is y%. After diversion, the flow rate of the third melt used for sodium extraction should be greater than or equal to y% × N g / h, so that the amount of sodium extracted from the third melt is y% × N g / h, or equivalent to or greater than y% × N g / h, as long as the Na element in the waste battery cathode material can be extracted through diversion. The remaining third melt is diverted and purified, and no further sodium extraction is performed. After purification, it is returned to the molten salt, thus achieving the reuse of the molten salt. When the amount of sodium extracted from the third melt is greater than y%×N g / h, it is actually a purification process for the molten salt, which is then returned to the molten salt for continued reuse.

[0170] For example, taking a sodium nickelate battery as an example, the Na content in the positive electrode material of a sodium nickelate battery is 18.7 wt%. Assuming that the flow rate of the third melt before diversion is 60 g / h, after diversion, the flow rate of the third melt used for sodium extraction should be greater than or equal to 11.2 g / h, so that the amount of sodium extracted from the third melt is 11.2 g / h, or the amount of sodium extracted from the third melt is equivalent to or greater than 11.2 g / h, as long as the Na element in the waste sodium nickelate battery positive electrode material can be extracted by diversion.

[0171] This application does not impose any particular restrictions on the physical form of the waste batteries, as long as they can achieve the purpose of this application. For example, they can be cylindrical batteries, square aluminum-cased batteries, soft-pack batteries, blade batteries, and the battery size can be 1#, 18650, etc.

[0172] This application does not impose any particular restrictions on the source of the cathode material from waste batteries, as long as it achieves the purpose of this application. For example, the cathode material can be obtained by dismantling and crushing waste batteries such as ternary lithium batteries, lithium cobalt oxide batteries, nickel-cobalt-aluminum lithium batteries, and sodium-ion batteries, or it can be obtained by crushing the cathodes discarded during the battery production process. The cathode material contains at least one target metal element selected from lithium, nickel, cobalt, and manganese. Specifically, this can be achieved by separating the cathode current collector and the cathode material layer from the dismantled or discarded cathode, crushing and sieving the cathode material layer to obtain the cathode material.

[0173] The second aspect of this application provides a waste battery recycling device that can separate impurity elements, non-lithium active metal elements Ni / Co / Mn, and Li / Na elements from the positive electrode material of waste batteries in steps, simplifying the impurity removal process and enabling the reuse of molten salt, thereby reducing costs.

[0174] In some embodiments of this application, as shown in Figures 4 and 5, the waste battery recycling device includes a pretreatment device 110, a melting device 120, a first impurity removal device 530, a non-lithium active metal element extraction device 540, a second impurity removal device 550, and a second metal element extraction device 560. The pretreatment device 110 includes a first inlet 511 and a first outlet 514; the melting device 120 includes a second inlet 521 and a second outlet 524; the first impurity removal device 530 includes a third inlet 621 and a third outlet 623; and the non-lithium active metal element extraction device 540... The active metal element extraction device 540 includes a fourth inlet 721 and a fourth outlet 723, and the second impurity removal device 550 includes a fifth inlet 821 and a fifth outlet 823; the first outlet 514 is connected to the second inlet 521; the second outlet 524 is connected to the third inlet 621; the third outlet 623 is connected to the fourth inlet 721; the fourth outlet 723 is connected to the fifth inlet 821; and the fifth outlet 823 is connected to the second metal element extraction device 560. The melting device 120 is used for chlorination. The above devices can achieve stepwise extraction, impurity removal, and recovery of impurities, non-lithium active metal elements, lithium elements, or sodium elements in waste battery cathode materials, simplifying the recovery process and improving recovery efficiency. This application does not particularly limit the form of the above "connection," and connection forms known in the art can be used, as long as the purpose of this application is achieved. For example, the above "connection" can be a pipeline connection.

[0175] In some embodiments of this application, as shown in Figures 4 and 5, the pretreatment device 110 further includes a pretreatment chamber 510, a magnetic separation crushing mixer 512, a first heating and insulation layer 515, and a screen 513. The magnetic separation crushing mixer 512 and the screen 513 are disposed inside the pretreatment chamber 510, and the magnetic separation crushing mixer 512 is located above the screen 513, which is located above the first discharge port 514. The first heating and insulation layer 515 is used to heat and control the temperature of the entire pretreatment chamber 510.

[0176] In some embodiments of this application, as shown in Figures 4 and 5, the melting device 120 further includes a melting chamber 520, a stirrer 522, a feeding and return port 523, and a second heating and insulation layer 525. The stirrer 522 is disposed inside the melting chamber 520, the feeding and return port 523 is disposed above the melting chamber 520 and communicates with the melting chamber 520, and the second heating and insulation layer 525 is used to heat and control the temperature of the entire melting chamber 520.

[0177] In some embodiments of this application, as shown in Figures 4 and 5, the first impurity removal device 530 further includes a first displacement impurity removal chamber 620, a first active metal plate 622, a first sedimentation outlet 624, a first sedimentation receiving tank 625, and a third heating and insulation layer 626. The first active metal plate 622 is located inside the first displacement impurity removal chamber 620, the first sedimentation receiving tank 625 is disposed at the bottom of the first displacement impurity removal chamber 620, the first sedimentation outlet 624 is located at the bottom of the first displacement impurity removal chamber 620 and communicates with the first sedimentation receiving tank 625, and the third heating and insulation layer 626 is used to heat and control the temperature of the entire first displacement impurity removal chamber 620.

[0178] In some embodiments of this application, as shown in Figures 4 and 5, the non-lithium active metal element extraction device 540 further includes a non-lithium active metal element displacement extraction chamber 720, a second active metal plate 722, a second precipitation outlet 724, a second precipitation receiving tank 725, and a fourth heating and insulation layer 726. The second active metal plate 722 is located inside the non-lithium active metal element displacement extraction chamber 720, the second precipitation receiving tank 725 is disposed at the bottom of the non-lithium active metal element displacement extraction chamber 720, the second precipitation outlet 724 is located at the bottom of the non-lithium active metal element displacement extraction chamber 720 and is connected to the second precipitation receiving tank 725, and the fourth heating and insulation layer 726 is used to heat and control the temperature of the entire non-lithium active metal element displacement extraction chamber 720.

[0179] In some embodiments of this application, as shown in Figures 4 and 5, the second impurity removal device 550 further includes a second displacement impurity removal chamber 820, a third active metal plate 822, a third sedimentation outlet 824, a third sedimentation receiving tank 825, and a fifth heating and insulation layer 826. The third active metal plate 822 is located inside the second displacement impurity removal chamber 820, the third sedimentation receiving tank 825 is disposed at the bottom of the second displacement impurity removal chamber 820, the third sedimentation outlet 824 is located at the bottom of the second displacement impurity removal chamber 820 and communicates with the third sedimentation receiving tank 825, and the fifth heating and insulation layer 826 is used to heat and control the temperature of the entire second displacement impurity removal chamber 820.

[0180] In some embodiments of this application, as shown in FIG4, the second metal element extraction device 560 includes an extraction extractor 930, a distillation extractor B 940 and a first dust collector 950 connected in sequence in a direction away from the second impurity removal device 550.

[0181] In some embodiments of this application, as shown in FIG4, the second metal element extraction device 560 further includes a diversion pipe 939 and a diversion valve 938. One end of the diversion pipe 939 and the diversion valve 938 are located between the fifth discharge port 823 and the sixth inlet port 931. The other end of the diversion pipe 939 is connected to the purification device 130, and the dryer 936 is connected to the diversion pipe 939.

[0182] As shown in Figure 4, the extractor 930 includes an extraction chamber 930A, a sixth inlet 931, a sixth outlet 933, a powder outlet 934, a sixth heating and insulation layer 935, a dryer 936, a solvent vapor pipeline 937, and a vapor reflux and replenishment inlet 932. As shown in Figure 4, the sixth inlet 931 and the sixth outlet 933 of the extractor 930 are located on the sidewalls of the extraction chamber 930A. When the extraction chamber 930A has four sidewalls, the sixth inlet 931 and the sixth outlet 933 are located on opposite sidewalls of the extraction chamber 930A. When the sidewalls of the extraction chamber 930A are entirely arc-shaped, the distance between the sixth inlet 931 and the sixth outlet 933 is approximately equal to the diameter of the arc. The powder outlet 934 is located at the bottom of the extraction chamber 930A and connected to the dryer 936. The vapor reflux and replenishment inlet 932 is located above the extraction chamber 930A. One end of the solvent vapor pipe 937 is connected to the vapor reflux and replenishment inlet 932, and the other end of the solvent vapor pipe 937 is connected to the dryer 936, so that the gaseous extractant evaporated from the dryer 936 can be returned to the extraction chamber 930A for reuse through the solvent vapor pipe 937. The insoluble solids discharged from the powder outlet 934 are dried by the dryer 936 and then discharged into the third impurity removal chamber 570 of the purification device 130 through the diversion pipe 939.

[0183] The distillation extractor B 940 includes a first distillation chamber 946, a seventh feed inlet 941, a seventh discharge outlet 942, a first product outlet 943, a first product collection tank 944, and a seventh heating and insulation layer 945. The seventh feed inlet 941 and the seventh discharge outlet 942 are located on the side walls of the first distillation chamber 946. When the first distillation chamber 946 has four side walls, the seventh feed inlet 941 and the seventh discharge outlet 942 are located on opposite side walls of the first distillation chamber 946. When the side walls of the first distillation chamber 946 are entirely arc-shaped, the distance between the seventh feed inlet 941 and the seventh discharge outlet 942 is approximately equal to the diameter of the arc. The sixth discharge port 933 is connected to the seventh feed port 941. The first product receiving tank 944 is located at the bottom of the first distillation chamber 946. The first product outlet 943 is located at the bottom of the first distillation chamber 946 and is connected to the first product receiving tank 944 for collecting products, such as LiCl.

[0184] The first dust collector 950 includes a first dust collection chamber 956, a first steam inlet 951, a first steam outlet 952, a first dust collection outlet 954, a first dust collection filter 953, and a first fine powder collection tank 955. The first steam inlet 951 and the first steam outlet 952 are located on the side walls of the first dust collection chamber 956. When the first dust collection chamber 956 has four side walls, the first steam inlet 951 and the first steam outlet 952 are located on opposite side walls of the first dust collection chamber 956. When the side walls of the first dust collection chamber 956 are entirely arc-shaped, the distance between the first steam inlet 951 and the first steam outlet 952 is approximately equal to the diameter of the arc. The seventh discharge port 942 is connected to the first steam inlet 951. The first dust collection filter 953 is located inside the first dust collection chamber 956. The first fine powder collection tank 955 is located at the bottom of the first dust collection chamber 956. The first dust collection outlet 954 is located at the bottom of the first dust collection chamber 956 and is connected to the first fine powder collection tank 955. The first steam outlet 952 is connected to the steam return and replenishment inlet 932 through a pipe so that the gaseous extractant can be returned to the extraction chamber 930A for reuse.

[0185] In some embodiments of this application, as shown in Figure 4, the height of the first discharge port 514 is higher than the height of the second feed port 521; the height of the second discharge port 524 is higher than the height of the third feed port 621; the height of the third discharge port 623 is higher than the height of the fourth feed port 721; the height of the fourth discharge port 723 is higher than the height of the fifth feed port 821; and the height of the fifth discharge port 823 is higher than the height of the sixth feed port 931. In some embodiments of this application, as shown in FIG4, the waste battery recycling device further includes a purification device 130 and a reflux device 140 connected sequentially in a direction away from the second metal element extraction device 560. The purification device 130 includes a third impurity removal chamber 570, a ninth feed inlet 571, an impurity removal system 572, a ninth discharge outlet 573, and a ninth heating and insulation layer 574. In the purification device 130, the impurity removal system 572 is located inside the third impurity removal chamber 570. The ninth feed inlet 571 and the ninth discharge outlet 573 are disposed on the side wall of the third impurity removal chamber 570. When the third impurity removal chamber 570 includes four side walls, the ninth feed inlet 571 and the ninth discharge outlet 573 are opened on the opposite side walls of the third impurity removal chamber 570. When the side wall of the third impurity removal chamber 570 is a complete arc shape, the distance between the ninth feed inlet 571 and the ninth discharge outlet 573 is approximately equal to the diameter of the arc. The purification device 130 is connected to the extraction extractor 930, specifically, the ninth inlet 571 and the other end of the branch line 939 are connected. The reflux device 140 includes a reflux pump assembly 580 and a reflux line 590. The reflux pump assembly 580 is connected to the ninth outlet 573, one end of the reflux line 590 is connected to the reflux pump assembly 580, and the other end of the reflux line 590 is connected to the feed and return port 523, used to return the remaining molten salt to the melting device 120 to continue participating in the reaction and / or act as a medium. That is, in this process, the ninth inlet 571 of the purification device 130 is connected to the branch line 939 of the second metal element extraction device 560, and the reflux device 140 is connected to the ninth outlet 573 of the purification device 130 and the feed and return port 523 of the melting device 120, used to return the molten salt to the melting device 120 for recycling.

[0186] The following describes some embodiments of this application. As shown in Figure 4, the lithium extraction process corresponding to the equipment is as follows: The sixth feed inlet 931 is equipped with a cooling and crushing facility (not shown in the figure). The molten salt bath at the sixth feed inlet 931 cools the powder into powder. The sixth heating and insulation layer 935 is used to heat and control the temperature of the entire extraction chamber 930A, ensuring that the LiCl in the powder fully dissolves in the extractant to form an extractant. The insoluble powder is discharged through the powder outlet 934 to the dryer 936. The dryer 936 is used to dry the extractant mixed in with the insoluble powder. After drying, the extractant returns to the extractor 930 in vapor form through the solvent vapor pipe 937 and the vapor reflux and replenishment inlet 932. The insoluble powder enters the third impurity removal chamber 570 through the diversion pipe 939 connected to the dryer 936. The sixth outlet 933 is equipped with a ceramic fine filter (not shown in the figure). The extractant flows out through the sixth outlet 933 to the distillation processor B 940. The seventh heating and insulation layer 945 is used to heat and control the temperature of the first distillation chamber 946, causing the extractant to evaporate. The obtained solid LiCl is recovered through the first product outlet 943 and the first product collection tank 944. The evaporated extractant is discharged through the seventh outlet 942 of the distillation extractor B 940 and enters the first steam inlet 951 of the first dust collector 950. The small amount of solid LiCl carried by the extractant is filtered through the first dust filter 953. The filtered extractant is discharged through the first steam outlet 952 and returns to the extractor 930 through the steam reflux and replenishment inlet 932. The small amount of solid LiCl is recovered through the first dust outlet 954 into the first fine powder collection tank 955.

[0187] In some embodiments of this application, as shown in FIG5, the second metal element extraction device 560 includes a distillation extractor A910 and a second dust collector 920 connected in sequence in a direction away from the second impurity removal device 550.

[0188] As shown in Figure 5, the distillation extractor A910 includes a second distillation chamber 916, an eighth feed inlet 911, an eighth discharge outlet 912, a second product outlet 913, a second product collection tank 914, and an eighth heating and insulation layer 915. The eighth feed inlet 911 and the eighth discharge outlet 912 are located on the side walls of the second distillation chamber 916. When the second distillation chamber 916 has four side walls, the eighth feed inlet 911 and the eighth discharge outlet 912 are located on opposite side walls of the second distillation chamber 916. When the side walls of the second distillation chamber 916 are entirely arc-shaped, the distance between the eighth feed inlet 911 and the eighth discharge outlet 912 is approximately equal to the diameter of the arc. The eighth feed inlet 911 is connected to the fifth discharge outlet 823 via a pipe. The second product collection tank 914 is located at the bottom of the second distillation chamber 916, and the second product outlet 913 is located at the bottom of the second distillation chamber 916 and connects to the second product collection tank 914.

[0189] The second dust collector 920 includes a second dust collection chamber 926, a second steam inlet 921, a second steam outlet 922, a second dust filter 923, a second dust outlet 924, and a second fine powder collection tank 925. An eighth discharge port 912 is connected to the second steam inlet 921 via a pipe. The second dust filter 923 is located inside the second dust collection chamber 926. The second fine powder collection tank 925 is located at the bottom of the second dust collection chamber 926. The second dust outlet 924 is located at the bottom of the second dust collection chamber 926 and communicates with the second fine powder collection tank 925.

[0190] In some embodiments of this application, as shown in FIG5, the second metal element extraction device 560 further includes a diversion pipe 939 and a diversion valve 938. One end of the diversion pipe 939 and the diversion valve 938 are located between the fifth discharge port 823 and the eighth inlet port 911. The other end of the diversion pipe 939 is connected to the purification device 130, and the second steam outlet 922 is connected to the diversion pipe 939 through a pipe.

[0191] In some embodiments of this application, as shown in Figure 5, the height of the first discharge port 514 is higher than the height of the second feed port 521; the height of the second discharge port 524 is higher than the height of the third feed port 621; the height of the third discharge port 623 is higher than the height of the fourth feed port 721; the height of the fourth discharge port 723 is higher than the height of the fifth feed port 821; and the height of the fifth discharge port 823 is higher than the height of the eighth feed port 911.

[0192] In some embodiments of this application, as shown in FIG5, the waste battery recycling device further includes a purification device 130 and a reflux device 140 connected sequentially in a direction away from the second metal element extraction device 560. The purification device 130 includes a third impurity removal chamber 570, a ninth inlet 571, an impurity removal system 572, a ninth outlet 573, and a ninth heating and insulation layer 574. The impurity removal system 572 is located inside the third impurity removal chamber 570. The ninth inlet 571 is connected to the other end of the diversion pipe 939. The second steam outlet 922 of the second dust collector 920 is connected to the diversion pipe 939 and is connected to the purification device 130 through the diversion pipe 939. The reflux device 140 includes a reflux pump assembly 580 and a reflux pipeline 590. The reflux pump assembly 580 is connected to the ninth discharge port 573. One end of the reflux pipeline 590 is connected to the reflux pump assembly 580, and the other end of the reflux pipeline 590 is connected to the feed and return port 523. It is used to return the remaining molten salt to the melting device 120 to continue participating in the reaction and / or to act as a medium. That is, in this process, the purification device 130 and the second metal element extraction device 560 are connected, and the reflux device 140 connects the purification device 130 and the melting device 120, and is used to reflux the molten salt back to the melting device 120.

[0193] The following describes some embodiments of this application. As shown in Figure 5, the lithium / sodium extraction process corresponding to the equipment is as follows: The eighth heating and insulation layer 915 is used to heat and control the temperature of the entire second distillation chamber 916, causing LiAlCl4 in the molten salt bath to decompose into LiCl and AlCl3, or NaAlCl4 in the molten salt bath to decompose into NaCl and AlCl3, and causing AlCl3 to evaporate at high temperature. The solid material obtained after evaporation (mainly including LiCl or NaCl) is recovered through the second product outlet 913 and the second product collection tank 914. The evaporated AlCl3 is discharged through the eighth outlet 912 and enters the second steam inlet 921 of the second dust collector 920. A small amount of solid LiCl carried in the gaseous AlCl3 is filtered by the second dust collector filter 923. The filtered gaseous AlCl3 is discharged from the second steam outlet 922 to the third impurity removal chamber 570. The small amount of solid LiCl obtained from the filtration enters the second fine powder collection tank 925 for recovery through the second dust collector outlet 924.

[0194] The specific implementation method of the waste battery recycling method of this application will be briefly described below with reference to the apparatus shown in Figures 4 and 5.

[0195] (1) The waste battery positive electrode material obtained from the treatment is fed into the pretreatment chamber 510 as shown in Figures 4 and 5 through the first feed inlet 511. A solid mixture is obtained by controlling the magnetic separation crusher and mixer 512 and the first heating and insulation layer 515. After being sieved through the screen 513, it is discharged from the first discharge outlet 514, thus completing the process of converting the waste battery positive electrode material into a solid mixture. If oxidation treatment is required, the oxidant can be added through the first feed inlet 511.

[0196] (2) The obtained solid mixture is fed into the melting chamber 520 as shown in Figures 4 and 5 through the second feed port 521. Molten salt is fed into the melting chamber 520 through the feeding and return port 523. The melting conditions are controlled by the second feed port 521, the stirrer 522 and the second heating and insulation layer 525. The solid mixture and molten salt are mixed to carry out a chlorination reaction to form a molten salt bath, which is then discharged through the second discharge port 524.

[0197] (3) The molten salt bath enters the first impurity removal device 530 as shown in Figures 4 and 5. The molten salt bath enters through the third feed port 621 of the first displacement impurity removal chamber 620. The temperature of the first displacement impurity removal chamber 620 is controlled by the third heating and heat preservation layer 626, so that the molten salt bath and the first active metal plate 622 undergo a displacement reaction to displace impurity a. Impurity a settles in the first displacement impurity removal chamber 620 to the first precipitation outlet 624 and is collected by the first precipitation collection tank 625. The remaining molten salt bath, i.e. the first melt, is discharged from the third discharge port 623 to the non-lithium active metal element extraction stage.

[0198] (4) The first melt after the first impurity removal stage enters the non-lithium active metal element extraction device 540 as shown in Figures 4 and 5. The first melt enters through the fourth inlet 721 of the non-lithium active metal element replacement extraction chamber 720. The temperature of the non-lithium active metal element replacement extraction chamber 720 is controlled by the fourth heating and insulation layer 726, so that the first melt reacts with the second active metal plate 722 to replace the non-lithium active metal nickel and / or cobalt. The non-lithium active metal settles in the non-lithium active metal element replacement extraction chamber 720 to the second precipitation outlet 724 and is collected by the second precipitation collection tank 725. The remaining molten salt bath, i.e. the second melt, is discharged from the fourth outlet 723 to the second impurity removal stage.

[0199] (5) The second molten liquid, after passing through the non-lithium active metal element extraction stage, enters the second impurity removal device 550 as shown in Figures 4 and 5. The second molten liquid enters through the fifth inlet 821 of the second displacement impurity removal chamber 820. The temperature of the second displacement impurity removal chamber 820 is controlled by the fifth heating and insulation layer 826, causing the second molten liquid to undergo a displacement reaction with the third active metal plate 822, displacing impurity b. Impurity b settles in the second displacement impurity removal chamber 820 to the third precipitation outlet 824 and is collected by the third precipitation collection tank 825. The remaining molten salt bath, i.e., the third molten liquid, is discharged from the fifth outlet 823 to the second metal element extraction stage. If the waste battery positive electrode material contains manganese, metallic manganese is also displaced in this stage.

[0200] (6) The third molten liquid after the second impurity removal stage enters the extraction device 560 for extracting the second metal element, as shown in Figures 4 and 5. Depending on the type of waste battery and the type of molten salt used, the extraction of the second metal element varies. The following examples are for illustrative purposes only:

[0201] ① When lithium battery cathode materials are combined with molten salts NaAlCl4 or KAlCl4, lithium can be extracted using extraction + distillation process B, as shown in Figure 4. The third molten liquid discharged through the fifth outlet 823 enters the extractor 930 through the diversion valve 938. Direct distillation process A is generally not used because the NaAlCl4 or KAlCl4 in the third molten liquid discharged through the fifth outlet 823 will decompose into NaCl or KCl at high temperatures, which is difficult to separate from LiCl.

[0202] ② When lithium battery cathode material is combined with molten salt LiAlCl4, lithium can be extracted using extraction + distillation method B, as shown in Figure 4. The third molten liquid discharged through the fifth outlet 823 is divided by the diversion valve 938. Part of it enters the third impurity removal chamber 570 through the diversion pipeline 939, and the other part enters the extraction extractor 930. The diversion flow rate is determined according to the Li element content in the cathode material.

[0203] ③ When the lithium battery cathode material is combined with molten salt LiAlCl4, lithium can be extracted by direct distillation process A, as shown in Figure 5. The third molten liquid discharged through the fifth outlet 823 is divided by the diversion valve 938. Part of it enters the third impurity removal chamber 570 through the diversion pipe 939, and the other part enters the lithium extraction distillation unit A910. The diversion flow rate is determined according to the Li element content in the cathode material.

[0204] ④ When the positive electrode material in a sodium battery is combined with molten salt NaAlCl4, sodium can be extracted using direct distillation process A, as shown in Figure 5. The third molten liquid discharged from the fifth outlet 823 is divided by the diversion valve 938. Part of it enters the third impurity removal chamber 570 through the diversion pipeline 939, and the other part enters the lithium extraction distillation unit A910. The diversion flow rate is determined according to the Na content in the positive electrode material. During high-temperature distillation, NaAlCl4 decomposes into NaCl and gaseous AlCl3. The NaCl generated during the chlorination reaction and the NaCl decomposed from NaAlCl4 precipitate into the second product collection tank 914. The NaAlO2 generated during the chlorination reaction also precipitates into the second product collection tank 914.

[0205] Here are some possible examples:

[0206] Example 1: In the lithium extraction section shown in Figure 4, the amount of the third melt flowing into the extractor 930 and the diversion pipe 939 is controlled by the diversion valve 938 according to the lithium content and the type of molten salt in the battery cathode material initially added to the pretreatment chamber 510. For example, when the cathode material contains Li and the molten salt is NaAlCl4 or KAlCl4, the third melt discharged from the fifth outlet 823 enters the extractor 930 entirely through the diversion valve 938. Specifically, the third melt used for lithium extraction is cooled and crushed into powder through the sixth inlet 931 with cooling and crushing facilities (not shown in the figure) and enters the extractor 930. The temperature of the extraction chamber 930A is controlled by the sixth heating and insulation layer 935. The LiCl in the powder is dissolved and extracted by the solvent. The solvent mixture includes, but is not limited to, one or more of water, acetone, cyclohexanone, methanol, ethanol, isopropanol, and diethyl ether. The remaining undissolved powder is discharged from the powder outlet 934, dried by the dryer 936, and then enters the third impurity removal chamber 570. The solvent mixed in the undissolved powder is evaporated in the dryer 936 and returned to the extractor 930 through the solvent vapor pipe 937. The lithium-ion-containing extract is discharged from the sixth outlet 933 with a ceramic fine filter (not shown in the figure) and enters the lithium distillation extractor B through the seventh inlet 941. In 940, the temperature of the second distillation chamber 946 is controlled by the seventh heating and insulation layer 945 to achieve solvent vaporization; the vapor is discharged from the seventh discharge port 942 and enters the first dust collector 950 through the first steam inlet 951, is filtered by the first dust collector filter 953, and after purification, it is discharged from the first steam outlet 952 and returned to the extractor 930 for recycling via the steam reflux and replenishment inlet 932; in the lithium distillation extractor B 940, the LiCl powder obtained by solvent evaporation is discharged to the first product collection tank 944 through the first product outlet 943; in the first dust collector 950, the filtered dust is discharged to the first fine powder collection tank 955 through the first dust collection outlet 954.

[0207] Example 2: In the lithium extraction section shown in Figure 5, the flow rate of the third melt into the distillation extractor A910 and the diversion line 939 is controlled by the diversion valve 938 according to the lithium or sodium content and the type of molten salt in the battery cathode material initially added to the pretreatment chamber 510. For example, when the cathode material contains Li and the molten salt is LiAlCl4, the third melt discharged from the fifth outlet 823 is diverted by the diversion valve 938 into the distillation lithium extractor A910 and the diversion line 939. The third melt not used for lithium extraction enters the third impurity removal chamber 570 through the diversion line 939; the third melt used for lithium extraction enters the distillation lithium extractor A910 through the eighth inlet 911. The temperature of the second distillation chamber 916 is controlled by the eighth heating and insulation layer 915, thereby evaporating the flux AlCl3 in the third melt and decomposing LiAlCl4 into LiCl and AlCl3. 3. The decomposed AlCl3 also evaporates; the vapor is discharged from the eighth outlet 912 and enters the second dust collector 920 through the second steam inlet 921. After being filtered by the second dust filter 923, the vapor is discharged from the second steam outlet 922 and enters the third impurity removal chamber 570. In the lithium distillation extractor A910, the solid lithium salt (containing a small amount of LiAlO2) left after the flux evaporates is discharged to the second product collection tank 914 through the second product outlet 913. In the second dust collector 920, the filtered dust is discharged to the second fine powder collection tank 925 through the second dust outlet 924.

[0208] (7) The third molten liquid after the second metal element extraction stage enters the purification device 130 as shown in Figures 4 and 5. The third molten liquid enters the third impurity removal chamber 570 through the ninth feed port 571 of the purification device. The temperature of the third impurity removal chamber 570 is controlled by the ninth heating and insulation layer 574. Under the action of the impurity removal system 572, by-products, impurities, etc. are removed, and the liquid is discharged to the reflux pump group 580 through the ninth discharge port 573.

[0209] (8) The third melt that passes through the third impurity removal chamber 570 enters the reflux pump group 580 shown in Figures 4 to 5, and then returns to the melting chamber 520 through the reflux pipeline 590 via the feeding and return port 523.

[0210] In summary, the waste battery recycling method provided in this application is based on a molten salt system and employs methods such as displacement, extraction, and distillation treatments B and A to extract high-value metal elements from waste batteries. This provides a low-cost, efficient, and environmentally friendly method and related apparatus for extracting and recovering metal elements from waste batteries.

[0211] The recovery and recycling of high-value metal elements from spent batteries is crucial for promoting the sustainable development of the battery industry and the new energy sector. However, traditional battery recycling methods, such as pyrometallurgical recovery, hydrometallurgical recovery, molten salt electrolysis, and traditional chlorination metallurgy, suffer from problems such as high costs due to large acid and alkali consumption, high levels of pollutants such as wastewater and waste salts, difficulty in recovering lithium, and low product recovery rates. Therefore, this application provides a battery recycling method and a battery recycling apparatus to reduce recycling costs, increase recycling yield, lower the recycling reaction temperature, and thus reduce the requirements for the recycling apparatus.

[0212] This application provides a method for recycling used batteries, which includes the following steps:

[0213] Pretreatment: The waste battery cathode material is pretreated to obtain a solid mixture; the solid mixture includes a first metal element, which is a non-lithium active metal element selected from at least one of nickel, cobalt, and manganese;

[0214] Obtaining a molten salt bath: A solid mixture is mixed with molten salt to obtain a molten salt bath;

[0215] First impurity removal stage: Remove impurity a; the metallic activity of impurity a is lower than that of either nickel or cobalt.

[0216] Non-lithium active metal element extraction stage: extraction of nickel and / or cobalt;

[0217] Second impurity removal stage: Remove impurity b; or, remove impurity b and extract metallic manganese; the metallic activity of impurity b is higher than that of either nickel or cobalt.

[0218] In the pretreatment stage or the molten salt bath stage, chlorination or sulfidation reactions are carried out.

[0219] In some embodiments of this application, pretreatment includes: pretreating the positive electrode material of the waste battery to obtain a solid mixture; including: pretreatment chlorination or pretreatment sulfation; pretreatment chlorination includes: mixing the positive electrode material with at least a chlorinating agent to carry out a chlorination reaction to obtain a solid mixture, the solid mixture including a chloride of a first metal element; pretreatment sulfation includes: mixing the positive electrode material with at least a sulfur source to carry out a sulfation reaction to obtain a solid mixture, the solid mixture including a sulfate of a first metal element. As shown in Figures 7a to 7c and Figures 8 to 10, the first aspect of this application also provides a waste battery recycling method, which includes the following steps:

[0220] S100, Pretreatment: The waste battery cathode material is pretreated to obtain a solid mixture. The pretreatment includes pretreatment chlorination or pretreatment sulfidation. The solid mixture includes a first metal element, which is a non-lithium active metal element selected from at least one of nickel, cobalt, and manganese.

[0221] The pretreatment chlorination includes: mixing the positive electrode material with at least a chlorinating agent to carry out a chlorination reaction to obtain a solid mixture, wherein the solid mixture includes a chloride of the first metal element;

[0222] Pretreatment sulfidation includes: mixing the cathode material with at least a sulfur source to carry out a sulfation reaction to obtain a solid mixture, wherein the solid mixture includes a sulfate of the first metal element;

[0223] S200, Obtaining a molten salt bath system: Mixing a solid mixture with molten salt, and melting it to form a molten salt bath;

[0224] S300, First impurity removal stage: Remove impurity a; the metallic activity of impurity a is lower than that of either nickel or cobalt.

[0225] S400, Non-lithium Active Metal Element Extraction Stage: Extraction of Nickel and / or Cobalt;

[0226] S500, Second impurity removal stage: Remove impurity b; or, remove impurity b and extract metallic manganese; the metallic activity of impurity b is higher than that of either nickel or cobalt.

[0227] The method provided in this application has the advantages of low cost, low consumption, high yield, energy saving, and environmental protection. In the pretreatment stage, waste battery cathode materials are converted into metal salts through chlorination or sulfation reactions, expanding the types of molten salts that can be used in the molten salt bath. Mixing the metal salts with the molten salt to form a molten salt bath provides a medium environment for electrolysis or displacement reactions, which is conducive to the full progress of the reaction. High-value metals in waste battery cathode materials can be extracted stepwise in the molten salt bath through electrolysis or displacement reactions, improving the recycling yield. Furthermore, the molten salt system has a lower reaction temperature, reducing the equipment requirements for electrolysis or displacement reactions; the reaction does not require the use of acids or alkalis, and no other harmful substances are generated. The molten salt can also be reused, reducing production costs and contributing to energy saving and environmental protection.

[0228] In some embodiments of this application, the pretreatment stage is a chlorination reaction. The chlorination reaction removes waste materials such as carbon and organic matter from the cathode material of the waste battery, while simultaneously causing elements such as Li, Co, Ni, and Mn to form chlorides. The chlorides can be melted into liquid in the molten salt at a lower temperature, partially miscible with the molten salt, and become ionic, thereby increasing the reaction rate and extent of subsequent electrolysis or displacement reactions.

[0229] In some embodiments of this application, the pretreatment stage is a sulfation reaction. The sulfation reaction removes waste materials such as carbon and organic matter from the cathode material of the waste battery, while simultaneously causing elements such as Li, Co, Ni, and Mn to form sulfides. The sulfides are solid in the molten salt, which provides a medium environment for subsequent electrolysis or displacement reactions.

[0230] In some embodiments of this application, before chlorination or sulfation, the waste battery cathode material can be treated by one or more of the following methods: grinding, magnetic separation, sieving, calcination at 300°C to 1000°C for 0.1h to 10h. After treatment, the cathode material is transformed into a state that is easier to extract, such as smaller particle size and fewer impurities.

[0231] For the pretreatment chlorination scheme:

[0232] In some embodiments of this application, the chlorinating agent in the pretreatment chlorination is selected from at least one of Cl2, NH4Cl, and HCl. Using the above-mentioned chlorinating agents can convert the oxides in the cathode materials of waste batteries into chlorides, i.e., chloride salts, which are easily extracted subsequently, simplifying the recycling process and reducing recycling costs.

[0233] In some embodiments of this application, the positive electrode material is mixed with a chlorinating agent to undergo a chlorination reaction to obtain a solid mixture, including: mixing the positive electrode material with a chlorinating agent to undergo a chlorination reaction to obtain a solid mixture. In some embodiments of this application, the molar amount of the first metal element in the positive electrode material is n1, the molar amount of the second metal element is n2, and the molar amount of Cl element in the chlorinating agent is n3, satisfying n3≥2n1+n2, where n1>0, n2≥0. For example, n3 is (2n1+n2), 1.2×(2n1+n2), 1.4×(2n1+n2), 1.5×(2n1+n2), 1.6×(2n1+n2), 2.0×(2n1+n2), etc. By controlling the molar amounts of the first metal element and the second metal element in the positive electrode material and the molar amount of Cl element in the chlorinating agent within the above ranges, the positive electrode material can react fully with the chlorinating agent, converting all oxides in the positive electrode material into chlorides and improving the recovery yield.

[0234] In some embodiments of this application, the positive electrode material is mixed with a chlorinating agent to undergo a chlorination reaction to obtain a solid mixture, including: mixing the positive electrode material with a chlorinating agent and a first reducing agent to undergo a chlorination reaction to obtain a solid mixture; wherein the first reducing agent is selected from at least one of coke, pulverized coal, NH4Cl, HCl, and CO. In some embodiments of this application, the molar amount of the first metal element in the positive electrode material is n1, the molar amount of the second metal element is n2, the molar amount of Cl element in the chlorinating agent is n3, and the molar amount of Cl element in the first reducing agent is n4, satisfying n3+n4≥2n1+n2, where n1>0, n2≥0, and n4≥0. For example, n3+n4 is (2n1+n2), 1.2×(2n1+n2), 1.4×(2n1+n2), 1.5×(2n1+n2), 1.6×(2n1+n2), 2.0×(2n1+n2), etc. Optionally, the molar ratio of the cathode material to the first reducing agent is 1:(0.2-5). The aforementioned first reducing agent can reduce high-valence elements such as Co, Ni, and Mn in the cathode material to lower valence states, such as +2, which is beneficial for subsequent extraction of Co, Ni, and Mn from the cathode material via electrolysis or displacement reactions. Furthermore, NH4Cl and HCl can be used simultaneously as chlorinating and reducing agents, or only as chlorinating agents; and after the reaction, NH4Cl is removed in the gaseous form of NH3 or N2, while after the reaction, HCl is removed in the gaseous form of Cl2, reducing or avoiding the introduction of impurities or excess water, thereby improving the purity of the molten salt bath and facilitating the subsequent metal extraction process via electrolysis or displacement reactions. By controlling the molar amounts of the first metal element, the second metal element, the Cl element in the chlorinating agent, and the Cl element in the first reducing agent to satisfy the above-mentioned relationship, and by controlling the molar ratio of the positive electrode material to the first reducing agent within the above-mentioned range, the positive electrode material can fully react with the chlorinating agent and the first reducing agent, converting the oxide in the positive electrode material into a low-valence chloride, thereby improving the recovery yield.

[0235] In some embodiments of this application, the cathode material includes LiMO2, M includes one or more of Mn, Co, Ni, etc., and NH4Cl is used as both the chlorinating agent and the first reducing agent. The chlorination reaction can be: 6LiMO2 + 18NH4Cl = 16NH3 + 6LiCl + 6MCl2 + N2 + 12H2O

[0236] In some embodiments of this application, the cathode material includes LiMO2, M includes one or more of Mn, Co, Ni, etc., Cl2 is used as the chlorinating agent, and coke is used as the first reducing agent. The chlorination reaction can be: 2LiMO2 + 3Cl2 + 2C = 2LiCl + 2MCl2 + 2CO2

[0237] In some embodiments of this application, the positive electrode material is mixed with at least a chlorinating agent to undergo a chlorination reaction to obtain a solid mixture, including: mixing the positive electrode material with a chlorinating agent, a first reducing agent, and a first oxidizing agent to undergo a chlorination reaction to obtain a solid mixture. The first reducing agent is selected from at least one of coke, pulverized coal, NH4Cl, HCl, and CO; the first oxidizing agent is selected from at least one of O2, O3, and MnO2. In some embodiments of this application, the molar amount of the first metal element in the positive electrode material is n1, the molar amount of the second metal element is n2, the molar amount of Cl in the chlorinating agent is n3, and the molar amount of Cl in the first reducing agent is n4, satisfying n3 + n4 ≥ 2n1 + n2, where n1 > 0, n2 ≥ 0, and n4 ≥ 0. For example, n3+n4 can be (2n1+n2), 1.2×(2n1+n2), 1.4×(2n1+n2), 1.5×(2n1+n2), 1.6×(2n1+n2), 2.0×(2n1+n2), etc. Optionally, the molar ratio of the positive electrode material to the first reducing agent and the first oxidizing agent is 1:(0.2~5):(0.2~5). The aforementioned first oxidizing agent can remove impurities such as carbon and organic matter from the positive electrode material of spent batteries. By controlling the molar amounts of the first metal element, the second metal element, the Cl element in the chlorinating agent, and the Cl element in the first reducing agent to satisfy the above-mentioned relationship, and by controlling the molar ratio of the positive electrode material to the first reducing agent and the first oxidizing agent to be within the above-mentioned range, impurities such as carbon and organic matter in the positive electrode material of waste batteries can be removed, improving the purity of the metal to be extracted. At the same time, the positive electrode material can be fully reacted with the chlorinating agent and the first reducing agent, converting all the oxides in the positive electrode material into low-valence chlorides, obtaining high-purity low-valence chlorides, and improving the recovery yield.

[0238] In some embodiments of this application, the conditions for the chlorination reaction include: a temperature T1 of 300℃ to 900℃ and a time t1 of 0.1h to 10h. For example, the temperature T1 can be 300℃, 400℃, 550℃, 700℃, 800℃, or 900℃, or any two of the above numbers; the time t1 can be 0.1h, 1h, 2h, 3.5h, 5h, 6h, 8h, 9h, or 10h, or any two of the above numbers. By controlling the reaction temperature and reaction time of the chlorination reaction within the above ranges, it is beneficial to promote the occurrence of the chlorination reaction, reduce unnecessary energy consumption while ensuring the reaction proceeds completely, and improve reaction efficiency.

[0239] In this process, when the oxide in the positive electrode material is converted into chloride, a chlorinating agent is required. When the elements such as Co, Ni, and Mn in the waste battery black powder are in a high valence state (e.g., +3 valence), in addition to the chlorinating agent, a first reducing agent is also needed to reduce the high valence elements such as Co, Ni, and Mn to a low valence state (e.g., +2 valence). When the elements such as Co, Ni, and Mn in the waste battery black powder are in a low valence state, only a chlorinating agent is needed. Those skilled in the art can select appropriate chlorinating agents, first reducing agents, and other substances according to the type of waste batteries that need to be treated based on the process provided in this application.

[0240] Preferably, NH4Cl can be used as both a chlorinating agent and a first reducing agent, or only as a chlorinating agent; and after the reaction, NH4Cl is removed in the gaseous form of NH3 or N2, reducing or avoiding the introduction of impurities or excess water, thereby improving the purity of the molten salt bath and facilitating the subsequent electrolysis / displacement extraction of metals.

[0241] Optionally, this process may further include a first oxidant, which includes one or more of O2, O3, and MnO2, wherein the molar ratio of the positive electrode material to the first oxidant is 1:(0.2-5). The first oxidant can remove impurities such as carbon and organic matter from waste battery black powder.

[0242] The following describes several possible implementation methods of this application:

[0243] 1) When the non-lithium active metal element in the positive electrode material of the waste battery is a low valence of +2, a chlorinating agent is required, such as one of NH4Cl or HCl, to react with the positive electrode material of the waste battery; two or more chlorinating agents can also be used.

[0244] 2) When the non-lithium active metal element in the waste battery black powder is in the high valence +3, both chlorinating agent and reducing agent are required. At this time, NH4Cl can be used to react directly with the waste battery positive electrode material. NH4Cl acts as both chlorinating agent and reducing agent. Alternatively, the above-mentioned first reducing agent and the above-mentioned chlorinating agent can be used to react with the waste battery positive electrode material.

[0245] 3) When the non-lithium active metal element in the cathode material of the waste battery is in the high-valence +3 state and the cathode material itself contains carbon, carbon acts as a reducing agent, and only a chlorinating agent needs to be added, such as any one of Cl2, NH4Cl, or HCl; other primary reducing agents can also be added appropriately on the basis of carbon reducing agent, such as CO, coke, coal powder, etc., which can be determined according to the actual situation of the cathode material of the waste battery to be processed.

[0246] For the pretreatment vulcanization scheme:

[0247] In some embodiments of this application, the sulfur source in the pretreatment sulfidation is selected from at least one of (NH4)2SO4, SO2, and H2SO4. Using these types of sulfur sources can convert the oxides in the cathode material of spent batteries into readily extractable sulfates, simplifying the recycling process and reducing recycling costs.

[0248] In some embodiments of this application, the cathode material is mixed with a sulfur source and subjected to a sulfation reaction to obtain a solid mixture, including: mixing the cathode material with a sulfur source and subjected to a sulfation reaction to obtain a solid mixture. In some embodiments of the application, the molar amount of the first metal element in the cathode material is n1, the molar amount of the second metal element is n2, and the molar amount of S element in the sulfur source is n5, satisfying n5≥n1+0.5n2, where n1>0 and n2≥0. For example, n5 can be (n1+0.5n2), 1.2×(n1+0.5n2), 1.4×(n1+0.5n2), 1.5×(n1+0.5n2), 1.6×(n1+0.5n2), 2.0×(n1+0.5n2), etc. By controlling the molar amounts of the first metal element, the second metal element, and the sulfur element in the sulfur source within the above ranges, the cathode material can fully react with the sulfur source, converting all the oxides in the cathode material into sulfates and improving the recovery yield.

[0249] In some embodiments of this application, the cathode material is mixed with at least a sulfur source and subjected to a sulfation reaction to obtain a solid mixture, including: mixing the cathode material with a sulfur source and a second reducing agent and subjected to a sulfation reaction to obtain a solid mixture; wherein the second reducing agent is selected from at least one of coke, pulverized coal, SO2, (NH4)2SO4, and CO. The molar amount of the first metal element in the cathode material is n1, the molar amount of the second metal element is n2, the molar amount of sulfur in the sulfur source is n5, and the molar amount of sulfur in the second reducing agent is n6, satisfying n5+n6≥n1+0.5n2, where n1>0, n2≥0, and n6≥0. For example, n5+n6 can be (n1+0.5n2), 1.2×(n1+0.5n2), 1.4×(n1+0.5n2), 1.5×(n1+0.5n2), 1.6×(n1+0.5n2), 2.0×(n1+0.5n2), etc. Furthermore, the molar ratio of the positive electrode material to the second reducing agent can be 1:(0.2~5). Additionally, SO2 or (NH4)2SO4 can be used simultaneously as a sulfur source and a second reducing agent; or (NH4)2SO4 can be used solely as a sulfur source; and after the reaction, (NH4)2SO4 can be removed in the gaseous form of NH3 or N2, reducing or avoiding the introduction of impurities or excess water, thereby improving the purity of the molten salt bath and facilitating subsequent electrolysis or displacement reactions to extract metals; using SO2 can avoid the introduction of other impurities. By controlling the molar amounts of the first metal element, the second metal element, the sulfur element in the sulfur source, and the sulfur element in the second reducing agent to satisfy the above-mentioned relationship, and by controlling the molar ratio of the cathode material to the second reducing agent within the above-mentioned range, the cathode material can fully react with the sulfur source and the second reducing agent, converting the oxide in the cathode material into a low-valence sulfate, thereby improving the recovery yield.

[0250] In some embodiments of this application, the cathode material includes LiMO2, M includes one or more of Mn, Co, Ni, etc., and (NH4)2SO4 is used as both the sulfur source and the second reducing agent. The sulfation reaction can be: 6LiMO2 + 9(NH4)2SO4 = 3Li2SO4 + 6MSO4 + 12H2O + 16NH3 + N2

[0251] In some embodiments of this application, the cathode material is mixed with at least a sulfur source to undergo a sulfation reaction to obtain a solid mixture, including: mixing the cathode material with a sulfur source, a second reducing agent, and a second oxidizing agent to undergo a sulfation reaction to obtain a solid mixture; wherein the second reducing agent is selected from at least one of coke, pulverized coal, SO2, (NH4)2SO4, and CO; the second oxidizing agent is selected from at least one of O2, O3, and MnO2; the molar amount of the first metal element in the cathode material is n1, and the molar amount of the second metal element is... The molar amount of sulfur in the cathode material is n2, the molar amount of sulfur in the sulfur source is n5, and the molar amount of sulfur in the second reducing agent is n6, satisfying n5 + n6 ≥ n1 + 0.5n2, where n1 > 0, n2 ≥ 0, and n6 ≥ 0. For example, n5 + n6 can be (n1 + 0.5n2), 1.2 × (n1 + 0.5n2), 1.4 × (n1 + 0.5n2), 1.5 × (n1 + 0.5n2), 1.6 × (n1 + 0.5n2), 2.0 × (n1 + 0.5n2), etc. Furthermore, the molar ratio of the cathode material, the second reducing agent, and the second oxidizing agent can be 1:(0.2~5):(0.2~5). The aforementioned second oxidizing agent can remove impurities such as carbon and organic matter from the cathode material of spent batteries. By controlling the proportions of the first metal element, the second metal element, the sulfur element in the sulfur source, and the sulfur element in the second reducing agent to satisfy the above-mentioned relationship, and by controlling the molar ratio of the positive electrode material to the second reducing agent and the second oxidizing agent within the above-mentioned range, impurities such as carbon and organic matter in the positive electrode material of waste batteries can be removed, allowing the positive electrode material to fully react with the sulfur source and the second reducing agent, converting all oxides in the positive electrode material into low-valence sulfates, obtaining high-purity low-valence sulfates, and improving the recycling yield.

[0252] In some embodiments of this application, the conditions for the sulfation reaction include: a temperature T1' of 300℃ to 900℃ and a time t1' of 0.1h to 10h. For example, the temperature T1' can be 300℃, 400℃, 500℃, 650℃, 800℃, or 900℃, or any two of the above numbers; the time t1' can be 0.1h, 1h, 2h, 3h, 4h, 6h, 8.5h, 9h, or 10h, or any two of the above numbers. By controlling the reaction temperature and reaction time of the sulfation reaction within the above ranges, it is beneficial to promote the occurrence of the sulfation reaction, reduce unnecessary energy consumption while ensuring the reaction proceeds completely, and improve reaction efficiency.

[0253] In this process, when the oxide in the positive electrode material is converted into sulfate, an sulfur source is required. When the elements such as Co, Ni, and Mn in the waste battery black powder are in a high valence state (e.g., +3 valence), in addition to the sulfur source, a second reducing agent is needed to reduce the high valence elements such as Co, Ni, and Mn to a low valence state (e.g., +2 valence). When the elements such as Co, Ni, and Mn in the waste battery black powder are in a low valence state, only an sulfur source is needed. Those skilled in the art can select appropriate sulfur sources, reducing agents, and other substances according to the type of waste batteries that need to be treated based on the process provided in this application.

[0254] Preferably, SO2 or (NH4)2SO4 can be used simultaneously as an S source and a second reducing agent; or (NH4)2SO4 can be used solely as an S source; and after the reaction, (NH4)2SO4 can be removed in the gaseous form of NH3 or N2, reducing or avoiding the introduction of impurities or excess water, thereby improving the purity of the molten salt bath and facilitating subsequent electrolytic / displacement metal extraction processes; the use of SO2 can avoid the introduction of other impurities.

[0255] The following describes several possible implementation methods of this application:

[0256] 1) When the non-lithium active metal element in the cathode material of waste batteries is low-valence +2, a sulfur source is required, such as (NH4)2SO4 or H2SO4, which can react with the cathode material of waste batteries; or a second oxidant and SO2 can be used to treat the low-valence cathode material of waste batteries to obtain sulfate.

[0257] 2) When the non-lithium active metal element in the cathode material of the waste battery is in the high valence +3, a sulfur source and a reducing agent are required. At this time, (NH4)2SO4 and / or SO2 can be used to react directly with the cathode material of the waste battery, or the above-mentioned second reducing agent and the above-mentioned sulfur source can be used to react with the cathode material of the waste battery.

[0258] 3) When the non-lithium active metal element in the cathode material of the waste battery is high-valence +3 and the cathode material itself contains carbon, carbon acts as a reducing agent, and only a sulfur source needs to be added, such as any one of (NH4)2SO4, SO2, and H2SO4; other reducing agents can also be added on the basis of carbon reducing agent, such as adding some CO, carbon powder, etc., which can be determined according to the actual situation of the cathode material of the waste battery to be processed.

[0259] In some embodiments of this application, in step S200, the melting temperature T2 is 200℃~800℃; preferably, the melting temperature T2 is 350℃~700℃; preferably, the mass ratio of the solid mixture to the molten salt is 1:3~1:20. For example, the melting temperature can be 200℃, 300℃, 400℃, 500℃, 600℃, 700℃ or 800℃, or any two of the above numbers; the mass ratio of the solid mixture to the molten salt can be 1:3, 1:5, 1:7, 1:8, 1:10, 1:12, 1:14, 1:15, 1:17 or 1:20, or any two of the above numbers. By controlling the melting temperature and the mass ratio of the solid mixture to the molten salt within the above ranges, a molten salt bath can be formed, providing a medium environment for subsequent electrolysis or displacement reactions, allowing the reaction to proceed at a lower temperature, reducing the requirements for reaction equipment, and lowering costs.

[0260] In summary, on the one hand, regarding the chlorides of the first metallic element, this process chlorinates valuable elements such as Li, Co, Ni, and Mn in the pretreatment stage. The resulting solid mixture is a chloride salt, which can be directly electrolyzed / displaced using the mixture of chloride salt and molten salt, reducing the introduction of impurities and improving the yield and purity of the metallic element. Furthermore, chlorination of the metallic element in the pretreatment stage allows for a wider variety of molten salts to be used in the subsequent molten salt bath to meet different environmental requirements. The molten salt bath system also allows for more complete subsequent electrolysis / displacement reactions, and its lower reaction temperature reduces the equipment requirements for electrolysis or displacement reactions, making it energy-efficient, environmentally friendly, and more conducive to industrial production. On the other hand, the sulfides of the first metallic element remain solid in the molten salt. The molten salt can provide a medium for the extraction of non-lithium active metallic elements in subsequent electrolysis or displacement reactions, but the reaction rate of these subsequent electrolysis or displacement reactions is lower than that of the chlorides of the first metallic element in the molten salt bath.

[0261] The following describes steps S300 to S500.

[0262] After the molten salt bath is formed in step S200, the first metallic element is extracted in the molten salt bath by electrolysis or displacement reaction through steps S300, S400 and S500.

[0263] Electrolytic extraction scheme for the first metallic element

[0264] In some embodiments of this application, step S300, the first impurity removal stage includes: performing a first electrolysis on the molten salt bath, and after precipitation, obtaining impurity a and a first molten liquid. In some embodiments of this application, the conditions for the first electrolysis include: the electrolysis voltage U1 is in the range of 0.5V ≤ U1 ≤ 1V, preferably 0.8V ≤ U1 ≤ 0.85V; and the electrolysis temperature T3 is in the range of 350℃ ≤ T3 ≤ 700℃. For example, the electrolysis voltage U1 can be 0.5V, 0.6V, 0.7V, 0.8V, 0.85V, or 1V, or any two of the above values; the electrolysis temperature T3 can be 350℃, 450℃, 550℃, 600℃, or 700℃, or any two of the above values. In some embodiments of this application, impurity a includes Cu element, and impurity a mainly originates from waste battery cathode materials. By controlling the electrolysis voltage U1 and electrolysis temperature T3 within the above range, the impurity Cu element can be removed, which facilitates the subsequent extraction of non-lithium active metal elements and improves the purity of non-lithium active metal elements.

[0265] In some embodiments of this application, step S400, the non-lithium active metal element extraction stage, includes: subjecting the first solution to a second electrolysis, followed by precipitation, extracting nickel and / or cobalt, and obtaining a second melt. In some embodiments of this application, the conditions for the second electrolysis include: the electrolysis voltage U2 is in the range of 1V < U2 ≤ 2.5V, preferably 1.8V ≤ U2 ≤ 1.9V; and the electrolysis temperature T4 is in the range of 350℃ ≤ T4 ≤ 700℃. For example, the electrolysis voltage U2 can be 1.1V, 1.4V, 1.6V, 1.8V, 1.9V, 2.2V, or 2.5V, or any two of the above values; the electrolysis temperature T4 can be 350℃, 450℃, 550℃, 600℃, or 700℃, or any two of the above values. By controlling the electrolysis voltage U2 and electrolysis temperature T4 within the above ranges, nickel and / or cobalt in the cathode material of waste batteries can be extracted.

[0266] In some embodiments of this application, the surface of the non-lithium active metal element extracted in step S400 is coated with molten salt and impurities. After washing the extracted non-lithium active metal element with a washing solution, it is magnetically adsorbed, as shown in Figure 15, to separate the non-lithium active metal element from the trapped molten salt and impurities, obtaining a pure non-lithium active metal. The remaining washing solution is evaporated and crystallized. The washing solution can be reused, and the crystallized product, i.e., the molten salt, is returned to the second melt to continue as molten salt for the next step of electrolytic depurification.

[0267] In some embodiments of this application, step S500, the second impurity removal stage includes: subjecting the second molten liquid to a third electrolysis, and after precipitation, obtaining impurity b and the third molten liquid. In some embodiments of this application, step S500, the second impurity removal stage includes: subjecting the second molten liquid to a third electrolysis, and after precipitation, obtaining impurity b, the third molten liquid, and metallic manganese. In some embodiments of this application, the conditions for the third electrolysis include: the electrolysis voltage U3 is in the range of 2.5V < U3 ≤ 3.5V, preferably 2.5V < U3 ≤ 2.7V; and the electrolysis temperature T5 is in the range of 350℃ ≤ T5 ≤ 700℃. For example, the electrolysis voltage U3 can be 2.6V, 2.7V, 3.0V, 3.2V, or 3.5V, or any two of the above values; the electrolysis temperature T5 can be 350℃, 450℃, 550℃, 600℃, or 700℃, or any two of the above values. In some embodiments of this application, impurity b includes at least one of Zn and Al elements, and impurity b mainly originates from waste battery cathode materials. By controlling the electrolysis voltage U3 and electrolysis temperature T5 within the aforementioned ranges, impurity elements such as Zn and Al can be removed. If the waste battery cathode material contains Mn, valuable Mn can be extracted in this step.

[0268] In some embodiments of this application, the cathode material of the waste battery does not contain Mn. The impurity b obtained in step S500 has molten salt attached to its surface. After washing the obtained impurity b with a washing solution, it is filtered, as shown in Figure 16. The first filtrate is evaporated and crystallized, and the crystallized product, i.e., molten salt, is returned to the third melt for reuse. The first filter residue is dissolved in water to separate the molten salt and impurity b, resulting in a second filter residue and a second filtrate. The second filter residue contains at least one of Al and Zn. The second filtrate is evaporated and crystallized, and the crystallized product is returned to the third melt for reuse.

[0269] In some embodiments of this application, the cathode material of the waste battery contains Mn. Impurity b and metallic manganese obtained in step S500 are coated with molten salt. After washing impurity b and metallic manganese with a washing solution and filtering, as shown in Figure 16, the first filtrate is evaporated and crystallized. The crystals, i.e., molten salt, are returned to the third melt for reuse. The first filter residue is dissolved in water to separate the carried-out molten salt, impurity b, and metallic manganese, yielding a second filter residue and a second filtrate. The second filter residue contains at least one of Al, Mn, and Zn. The second filtrate is evaporated and crystallized, and the crystals are returned to the third melt for reuse.

[0270] The voltage in the above electrolysis process satisfies U1 < U2 < U3. By gradually increasing the electrolysis voltage, non-lithium active metal elements in the cathode material of waste batteries can be extracted step by step, making it easier to extract metal substances at each stage, improving the purity and yield of battery recycling. Moreover, the step-by-step electrolysis temperature is relatively low, which helps to reduce costs.

[0271] In this application, the electrolysis temperatures of the first electrolysis, the second electrolysis, and the third electrolysis can be the same or different, as long as they can achieve the purpose of this application within the scope of this application.

[0272] In some embodiments of this application, the cathode and anode in the first, second, and third electrolysis are independently selected from any one of the inert electrodes; the inert electrodes include one of nickel plates, copper plates, stainless steel plates, graphite plates, platinum plates, and silver plates. The above-mentioned types of inert electrodes can maintain long-term stability in a molten salt bath under oxidation or reduction potentials, with a corrosion rate of less than 0.01 mm / h, which helps to reduce the introduction of impurity elements and improve the purity of the recovered material.

[0273] In some embodiments of this application, non-lithium active metal elements are extracted by electrolytic reaction. The molten salt is selected from at least one of LiCl, NaCl, KCl, AlCl3, ZnCl2, NaBr, KBr, Na2CO3, K2CO3, Na2SO4, and KNO3. When extracting metal elements by electrolysis, the above-mentioned types of molten salts are selected because they can form a molten salt bath with the solid mixture, providing a medium environment for subsequent electrolysis, reducing the introduction of impurities, and allowing electrolysis to be carried out at a lower temperature, reducing the requirements for reaction equipment and lowering costs.

[0274] For the extraction of elements such as Ni, Co, and Mn using electrolysis, firstly, the chlorides of the primary metal elements can dissolve into a liquid state in the molten salt and partially miscible with the molten salt, becoming ionic. The chlorides diffuse rapidly and uniformly in the molten salt bath, which is more conducive to the electrolysis process. This allows for stepwise electrolysis of different metal elements at relatively low temperatures and with a fast electrolysis rate. Secondly, the chlorine gas produced during electrolysis escapes directly without affecting the pH of the molten salt system or introducing impurities. In contrast, in an aqueous system, the pH decreases due to Cl2 dissolution, requiring the addition of... Alkali adjustment of pH is required for electrolysis. Typically, NaOH or KOH is introduced during electrolysis. The introduction of alkali destabilizes the system and introduces impurities such as K and Na. K and Na are similar in properties to Li and are difficult to separate, leading to low LiCl purity. Furthermore, because chlorides have good diffusion properties, high-current electrolysis can be used, especially in the extraction stage of non-lithium active metals. Since the molten salt bath contains a high concentration of non-lithium active metals, high-current electrolysis, such as 20A–30A, increases the production capacity of non-lithium active metals per unit time.

[0275] Displacement extraction scheme for the first metallic element

[0276] In some embodiments of this application, step S300 includes a first impurity removal stage comprising: subjecting a molten salt bath to a first active metal plate in a first displacement reaction, and after precipitation, obtaining impurity a and a first molten liquid. In some embodiments of this application, the material of the first active metal plate is selected from any one of cobalt and nickel or their alloys; the reaction temperature T3' of the first displacement reaction is 300℃~400℃, and the reaction time t3' is 1h~10h. For example, the reaction temperature of the first displacement reaction can be 300℃, 320℃, 350℃, 380℃, or 400℃, or any two of the above numbers. For example, the reaction time of the first displacement reaction can be 1h, 3h, 5h, 8h, or 10h, or any two of the above numbers. In some embodiments of this application, impurity a includes Cu element, and impurity a mainly originates from waste battery cathode materials. The above-described displacement reaction can effectively remove impurity 'a' from the molten salt bath. Using a metal plate with a higher reactivity than impurity 'a' but lower reactivity than or equal to that of the non-lithium active metal element, such as a cobalt plate, avoids introducing other impurities, allowing the non-lithium active metal elements Co and / or Ni to be extracted during the non-lithium active metal element extraction stage. Removing impurity 'a' from the waste battery cathode material first facilitates the subsequent extraction of non-lithium active metal elements and improves their purity.

[0277] In some embodiments of this application, step S400, the non-lithium active metal element extraction stage, includes: subjecting the first molten liquid to a second active metal plate in a second displacement reaction; after precipitation, extracting nickel and / or cobalt, and obtaining the second molten liquid. In some embodiments of this application, the material of the second active metal plate is selected from any one of zinc and manganese or their alloys; the reaction temperature T4' of the second displacement reaction is 300℃~400℃, and the reaction time t4' is 1h~5h. For example, the reaction temperature of the second displacement reaction can be 300℃, 320℃, 350℃, 380℃, or 400℃, or any two of the above numbers. For example, the reaction time of the second displacement reaction can be 1h, 2h, 3h, 4h, or 5h, or any two of the above numbers. Through the above displacement reaction, non-lithium active metals nickel and / or cobalt in the molten salt bath can be fully displaced. Using metal plates with higher reactivity than Co and / or Ni, but lower reactivity than or equal to impurity elements such as Zn, for example, directly using Zn plates, avoids introducing more impurities. This allows Zn to be displaced in the second impurity removal stage.

[0278] In some embodiments of this application, step S500, the second impurity removal stage includes: subjecting the second molten liquid to a third displacement reaction with the third active metal plate, and after precipitation, obtaining impurity b and the third molten liquid. In some embodiments of this application, step S500, the second impurity removal stage includes: subjecting the second molten liquid to a third displacement reaction with the third active metal plate, and after precipitation, obtaining impurity b, the third molten liquid, and metallic manganese. In some embodiments of this application, the material of the third active metal plate is selected from aluminum metal or its alloys; the reaction temperature T5' of the third displacement reaction is 300℃~400℃, and the reaction time t5' is 2h~10h. For example, the reaction temperature of the third displacement reaction can be 300℃, 320℃, 350℃, 380℃, or 400℃, or any two of the above numbers. For example, the reaction time of the third displacement reaction can be 2h, 3h, 5h, 7h, 9h, or 10h, or any two of the above numbers. In some embodiments of this application, impurity b includes at least one of Zn and Al elements. Impurity b mainly originates from the cathode material of spent batteries, or primarily from the active metal plate used in the second displacement reaction. Through the aforementioned displacement reaction, impurity b in the molten salt bath can be thoroughly removed. If the spent battery cathode material contains manganese, valuable manganese can also be extracted in this step. Using a metal plate with higher reactivity than impurity b and manganese, and which is easily separated from the Li or Na elements in subsequent lithium or sodium extraction stages, such as an Al plate, simplifies the recycling process, reduces costs, and increases the recycling yield. Removing impurity b from the molten salt bath facilitates the subsequent extraction of lithium or sodium, improving the purity of the lithium or sodium elements.

[0279] By using the aforementioned first, second, and third active metal plates, non-lithium active metal elements, Li / Na elements, and impurity elements in the cathode material of spent batteries can be separated stepwise. This effectively recovers non-lithium active metal elements Ni / Co / Mn and Li / Na elements from spent batteries, simplifying the recycling process and avoiding the introduction of other impurities. By controlling the reaction temperature and reaction time of the first, second, and third replacement reactions within the aforementioned range, impurities a, non-lithium active metal elements, and impurities b in the molten salt bath can be fully replaced, thereby improving the recovery yield and purity of Ni / Co / Mn and Li / Na.

[0280] In this application, the reaction temperatures of the first displacement reaction, the second displacement reaction, and the third displacement reaction can be the same or different, as long as they can achieve the purpose of this application within the scope of this application.

[0281] In some embodiments of this application, non-lithium active metal elements are extracted via a displacement reaction. The molten salt is selected from at least one of LiCl, NaCl, KCl, AlCl3, ZnCl2, NaBr, KBr, Na2CO3, K2CO3, Na2SO4, KNO3, NaAlCl4, LiAlCl4, and KAlCl4. When extracting metal elements using the displacement method, the aforementioned types of molten salts are chosen because they can form a molten salt bath with the solid mixture, providing a suitable medium for the subsequent displacement reaction, reducing the introduction of impurities, and allowing the displacement reaction to proceed at lower temperatures, thus reducing the requirements for reaction equipment and lowering costs.

[0282] For the extraction of elements such as Ni, Co, and Mn using displacement processes in molten salt baths, the chlorides are partially miscible with the molten salt at lower temperatures, and the liquid chlorides can form a solid-liquid interface with the metal plate, which is more conducive to the displacement reaction and increases the reaction rate and extent. At the same time, it also allows the stepwise displacement reaction to be carried out at lower temperatures.

[0283] The recycling of second metallic elements (such as Li) will be discussed next.

[0284] In some embodiments of this application, the solid mixture further includes a second metal element selected from either lithium or sodium; the waste battery recycling method further includes the following steps: S600, second metal element extraction stage: extracting the second metal element from the third melt.

[0285] In some embodiments of this application, the extraction of the second metallic element from the third melt includes three methods:

[0286] Method 1: Directly distill the third molten liquid to extract the second metallic element.

[0287] In some embodiments of this application, distillation process A includes heating the third melt at a temperature T6', where T6' is 480°C to 550°C, to evaporate the AlCl3 in the third melt and obtain a solid second metal chloride. For example, the heating temperature of distillation process A can be 480°C, 490°C, 500°C, 510°C, 530°C, 540°C, or 550°C, or any two of the above values.

[0288] In some embodiments of this application, the second metal element is selected from lithium, and the molten salt is LiAlCl4, or the molten salt is LiCl and LiAlCl4. Based on the above selection of the molten salt, step S600, the extraction stage of the second metal element, includes: splitting the third melt, extracting lithium from a portion, and returning the other portion to the molten salt after impurity removal; wherein, lithium extraction includes: directly subjecting a portion of the split third melt to distillation treatment A to extract Li element. By heating the third melt within the above-mentioned temperature range T6', the molten salt LiAlCl4 can be decomposed into LiCl and AlCl3. AlCl3 will evaporate within this temperature range to obtain solid LiCl, thereby realizing the extraction of Li element from the cathode material of waste batteries.

[0289] In some embodiments of this application, the second metal element is selected from sodium, and the molten salt is NaAlCl4, or the molten salt is NaCl and NaAlCl4. Based on the above selection of the molten salt, step S600, the extraction stage of the second metal element, includes: splitting the third molten liquid, extracting sodium from one portion, and returning the other portion to the molten salt after impurity removal; wherein, sodium extraction includes: directly subjecting a portion of the split third molten liquid to distillation treatment A to extract Na element. Through the above distillation treatment A, the molten salt NaAlCl4 can be decomposed into NaCl and AlCl3, and AlCl3 evaporates to obtain solid NaCl, thereby realizing the extraction of Na element from the cathode material of waste batteries.

[0290] Method 2: First, extract the third melt, and then distill the resulting extract to extract the second metal element.

[0291] In some embodiments of this application, the extraction process includes: cooling the third melt and crushing it into powder, dissolving the LiCl in the powder using an extractant to obtain an extract, wherein the extractant is selected from at least one of acetone, cyclohexanone, methanol, ethanol, isopropanol, and diethyl ether; the distillation process B includes: heating the extract at a temperature T6, where T6 is 60°C to 200°C, to evaporate the extractant in the extract and obtain LiCl. For example, the heating temperature of the extract can be 60°C, 80°C, 100°C, 120°C, 140°C, 150°C, 170°C, 190°C, or 200°C, or any two of the above numbers.

[0292] In some embodiments of this application, the second metal element is selected from lithium, and the molten salt is selected from a molten salt that does not contain lithium. Step S600, the stage of extracting the second metal element, includes: extracting lithium from the entire third molten liquid; wherein, lithium extraction includes: first extracting the third molten liquid, and then subjecting the resulting extract to distillation treatment B to extract Li. By selecting a suitable extractant, LiCl in the powder can be dissolved, and distillation treatment B can evaporate the extractant in LiCl to obtain solid LiCl, thereby improving the purity of LiCl.

[0293] In some embodiments of this application, the second metal element is selected from lithium, the molten salt includes LiCl and / or LiAlCl4, and optionally a molten salt without lithium. Step S600, the extraction stage of the second metal element, includes: splitting the third molten liquid, extracting lithium from one portion, and returning the other portion to the molten salt after impurity removal; wherein, lithium extraction includes: first extracting a portion of the split third molten liquid, and then performing a distillation process B to extract Li. By selecting a suitable extractant, LiCl can be dissolved, and the distillation process B can evaporate the extractant in LiCl to obtain solid LiCl, thereby improving the purity of LiCl.

[0294] For example, the second metal element is selected from lithium, and the molten salt is LiAlCl4 and optionally a molten salt without lithium, or the molten salt is LiCl and optionally a molten salt without lithium, or the molten salt is LiAlCl4 and LiCl and optionally a molten salt without lithium. Based on the above selection of molten salt, step S600, the stage of extracting the second metal element, includes: splitting the third melt, extracting lithium from one part, and returning the other part to the molten salt after impurity removal; wherein, lithium extraction includes: first extracting the split portion of the third melt, and then performing distillation treatment B to extract Li. By selecting a suitable extractant, LiCl can be dissolved, and distillation treatment B can evaporate the extractant in LiCl to obtain solid LiCl, thereby improving the purity of LiCl.

[0295] Method 3: Cool the third melt to crystallize and extract the second metallic element.

[0296] In some embodiments of this application, cooling crystallization includes: cooling the third melt to T6”, causing the second metal chloride in the third melt to precipitate, thereby obtaining a solid second metal chloride. The second metal element is lithium, and T6” is 345°C to 360°C. For example, T6” can be 345°C, 350°C, 352°C, 357°C, or 360°C, or any two of the above numbers. The second metal element is sodium, and T6” is 420°C to 500°C. For example, T6” can be 420°C, 450°C, 462°C, 487°C, or 500°C, or any two of the above numbers.

[0297] In some embodiments of this application, the second metal element is selected from lithium, and the molten salt is KCl, or LiCl and KCl. Step S600, the stage for extracting the second metal element, includes: extracting lithium from all of the third melt; or, splitting the third melt, extracting lithium from one portion and returning the other portion to the molten salt after impurity removal; wherein, lithium extraction includes: cooling and crystallizing the third melt to extract Li. Extracting the second metal chloride using the above-mentioned cooling and crystallization method can reduce the introduction of impurities, simplify the extraction process, and is more energy-efficient and environmentally friendly.

[0298] In some embodiments of this application, the second metal element is selected from sodium, and the molten salt is selected from KCl, or from NaCl and KCl. Step S600, the extraction stage of the second metal element, includes: extracting sodium from all of the third molten liquid; or, splitting the third molten liquid, extracting sodium from one portion and returning the other portion to the molten salt after impurity removal; wherein, sodium extraction includes: cooling and crystallizing the third molten liquid to extract Na. Extracting the second metal chloride using the above-mentioned cooling and crystallization method can reduce the introduction of impurities, simplify the extraction process, and is more energy-efficient and environmentally friendly.

[0299] When the second metallic element is Li, there is no particular limitation on the flow rate of the third melt. The goal is simply to extract Li from the spent battery cathode material through this flow separation, avoiding unnecessary energy consumption from heating the molten salt LiAlCl4 and enabling the reuse of the molten salt. In actual production, the amount of lithium extracted from the third melt can be adjusted according to actual needs, and the actual flow rate of the third melt can also be adjusted based on the actual amount of lithium extracted. For example, based on the Li content in the spent battery cathode material, the flow rate of the third melt before separation is M g / h, and the mass percentage of Li in the cathode material is x%. After separation, the flow rate of the third melt used for lithium extraction can be greater than or equal to x% × M g / h, so that the amount of lithium extracted from the third melt is x% × M g / h, or equivalent to or greater than x% × M g / h, as long as Li from the spent battery cathode material can be extracted through this flow separation. The remaining third melt is diverted and purified, and no further lithium extraction is performed. After purification, it is returned to the molten salt, thus achieving the reuse of the molten salt. When the amount of lithium extracted from the third melt is greater than x% × M g / h, it is actually a purification process of the molten salt, which is then returned to the molten salt for continued reuse.

[0300] For example, taking a lithium cobalt oxide battery as an example, the Li content in the positive electrode material of the lithium cobalt oxide battery is 6.45 wt%. Assuming that the flow rate of the third melt before diversion is 60 g / h, after diversion, the flow rate of the third melt used for lithium extraction should be greater than or equal to 3.87 g / h, so that the amount of lithium extracted from the third melt is 3.87 g / h, or the amount of lithium extracted from the third melt is equivalent to or greater than 3.87 g / h, as long as the Li element in the waste lithium cobalt oxide battery positive electrode material can be extracted by diversion.

[0301] When the second metallic element is Na, the flow rate of the third melt is not particularly limited. The goal is simply to extract Na from the waste battery cathode material through a diversion process, avoiding energy consumption from heating the molten salt NaAlCl4 and enabling the reuse of the molten salt. In actual production, the amount of sodium extracted from the third melt can be adjusted according to actual needs, and the actual flow rate of the third melt can also be adjusted based on the actual amount of sodium extracted. For example, based on the Na content in the waste battery cathode material, the flow rate of the third melt before diversion is N g / h, and the mass percentage of Na in the cathode material is y%. After diversion, the flow rate of the third melt used for sodium extraction should be greater than or equal to y% × N g / h, so that the amount of sodium extracted from the third melt is y% × N g / h, or equivalent to or greater than y% × N g / h, as long as Na from the waste battery cathode material can be extracted through diversion. The remaining third melt is diverted and no longer used for sodium extraction. After impurity removal, it is returned to the molten salt, thus achieving the reuse of the molten salt. When the amount of sodium extracted from the third melt is greater than y%×N g / h, it is actually a process of impurity removal from the molten salt, which is then returned to the molten salt for continued reuse.

[0302] For example, taking a sodium nickelate battery as an example, the Na content in the positive electrode material of a sodium nickelate battery is 18.7 wt%. Assuming that the flow rate of the third melt before diversion is 60 g / h, after diversion, the flow rate of the third melt used for sodium extraction should be greater than or equal to 11.2 g / h, so that the amount of sodium extracted from the third melt is 11.2 g / h, or the amount of sodium extracted from the third melt is equivalent to or greater than 11.2 g / h, as long as the Na element in the waste sodium nickelate battery positive electrode material can be extracted by diversion.

[0303] In some embodiments of this application, a pretreatment sulfidation method is used to treat the cathode material of waste batteries. The resulting solid mixture includes sulfates of a first metal element and sulfates of a second metal element. The sulfates remain solid in the molten salt. When extracting the second metal element, lithium sulfate or sodium sulfate can be directly extracted by filtration.

[0304] This application does not impose any particular restrictions on the physical form of the waste batteries, as long as they can achieve the purpose of this application. For example, they can be cylindrical batteries, square aluminum-cased batteries, soft-pack batteries, blade batteries, and the battery size can be 1#, 18650, etc.

[0305] This application does not impose any particular restrictions on the source of the cathode material from waste batteries, as long as it achieves the purpose of this application. For example, the cathode material can be obtained by dismantling and crushing waste batteries such as ternary lithium batteries, lithium cobalt oxide batteries, nickel-cobalt-aluminum lithium batteries, and sodium-ion batteries, or it can be obtained by crushing the cathodes discarded during the battery production process. The cathode material contains at least one target metal element selected from lithium, nickel, cobalt, and manganese. Specifically, this can be achieved by separating the cathode current collector and the cathode material layer from the dismantled or discarded cathode, crushing and sieving the cathode material layer to obtain the cathode material.

[0306] The second aspect of this application provides a waste battery recycling device that can separate impurity elements, non-lithium active metal elements Ni / Co / Mn, and Li / Na elements from the positive electrode material of waste batteries in steps, simplifying the impurity removal process and enabling the reuse of molten salt, thereby reducing costs.

[0307] In some embodiments of this application, as shown in Figures 11 to 14, the waste battery recycling device includes a pretreatment device 110, a melting device 120, a first impurity removal device 530, a non-lithium active metal element extraction device 540, and a second impurity removal device 550 connected in sequence.

[0308] In some embodiments of this application, as shown in Figures 11 and 13, the pretreatment device includes a first feed inlet 511, a first discharge outlet 514, a pretreatment chamber 510, a magnetic separation crushing mixer 512, a first heating and insulation layer 515, and a screen 513. The magnetic separation crushing mixer 512 and the screen 513 are disposed inside the pretreatment chamber 510, with the magnetic separation crushing mixer 512 located above the screen 513 and the screen 513 located above the first discharge outlet 514. The first heating and insulation layer 515 is used to heat and control the temperature of the entire pretreatment chamber 510.

[0309] Referring again to Figures 11 and 13, the melting device 120 includes a second inlet 521, a second outlet 524, a melting chamber 520, a stirrer 522, a feeding and return outlet 523, and a second heating and insulation layer 525. The stirrer 522 is located inside the melting chamber 520, the feeding and return outlet 523 is located above the melting chamber 520, and the second heating and insulation layer 525 is used to heat and control the temperature of the entire melting chamber 520.

[0310] As shown in Figures 11 and 13, the first impurity removal device 530 includes a third inlet 611, a third outlet 614, a first electrostatic impurity removal chamber 610, a first anode inert electrode plate 612, a first cathode inert electrode plate 613, a first sedimentation collection tank 616, a first sedimentation outlet 615, and a third heating and insulation layer 617. The first anode inert electrode plate 612 and the first cathode inert electrode plate 613 are located inside the first electrostatic impurity removal chamber 610. The first sedimentation collection tank 616 is located at the bottom of the first electrostatic impurity removal chamber 610. The first sedimentation outlet 615 is located at the bottom of the first electrostatic impurity removal chamber 610 and is connected to the first sedimentation collection tank 616. The third heating and insulation layer 617 is used to heat and control the temperature of the entire first electrostatic impurity removal chamber 610.

[0311] As shown in Figures 11 and 13, the non-lithium active metal element extraction device 540 includes a fourth inlet 711, a fourth outlet 714, a non-lithium active metal element electrolytic extraction chamber 710, a second anode inert electrode plate 712, a second cathode inert electrode plate 713, a second precipitation collection tank 716, a second precipitation outlet 715, and a fourth heating and insulation layer 717. The second anode inert electrode plate 712 and the second cathode inert electrode plate 713 are located inside the non-lithium active metal element electrolytic extraction chamber 710. The second precipitation collection tank 716 is located at the bottom of the non-lithium active metal element electrolytic extraction chamber 710, and the second precipitation outlet 715 is located at the bottom of the non-lithium active metal element electrolytic extraction chamber 710 and is connected to the second precipitation collection tank 716. The fourth heating and insulation layer 717 is used to heat and control the temperature of the entire non-lithium active metal element electrolytic extraction chamber 710.

[0312] As shown in Figures 11 and 13, the second impurity removal device 550 includes a fifth inlet 811, a fifth outlet 814, a second electrostatic impurity removal chamber 810, a third anode inert electrode plate 812, a third cathode inert electrode plate 813, a third sedimentation collection tank 816, a third sedimentation outlet 815, and a fifth heating and insulation layer 817. The third anode inert electrode plate 812 and the third cathode inert electrode plate 813 are located inside the second electrostatic impurity removal chamber 810. The third sedimentation collection tank 816 is located at the bottom of the second electrostatic impurity removal chamber 810. The third sedimentation outlet 815 is located at the bottom of the second electrostatic impurity removal chamber 810 and is connected to the third sedimentation collection tank 816. The fifth heating and insulation layer 817 is used to heat and control the temperature of the entire first electrostatic impurity removal chamber 610.

[0313] As shown in Figures 11 and 13, the first discharge port 514 is connected to the second feed port 521, the second discharge port 524 is connected to the third feed port 611, the third discharge port 614 is connected to the fourth feed port 711, and the fourth discharge port 714 is connected to the fifth feed port 811.

[0314] In some other embodiments of this application, as shown in Figures 12 and 14, the pretreatment device includes a first feed inlet 511, a first discharge outlet 514, a pretreatment chamber 510, a magnetic separation crushing mixer 512, a first heating and insulation layer 515, and a screen 513; the magnetic separation crushing mixer 512 and the screen 513 are disposed inside the pretreatment chamber 510, and the magnetic separation crushing mixer 512 is located above the screen 513, and the screen 513 is located above the first discharge outlet 514; the first heating and insulation layer 515 is used to heat and control the temperature of the entire pretreatment chamber 510.

[0315] Referring again to Figures 12 and 14, the melting device 120 includes a second inlet 521, a second outlet 524, a melting chamber 520, a stirrer 522, a feeding and return outlet 523, and a second heating and insulation layer 525. The stirrer 522 is located inside the melting chamber 520, the feeding and return outlet 523 is located above the melting chamber 520, and the second heating and insulation layer 525 is used to heat and control the temperature of the entire melting chamber 520.

[0316] As shown in Figures 12 and 14, the first impurity removal device 530 includes a sixth inlet 621, a sixth outlet 623, a first displacement impurity removal chamber 620, a first active metal plate 622, a fourth precipitation outlet 624, a fourth precipitation receiving tank 625, and a sixth heating and insulation layer 626. The first active metal plate 622 is located inside the first displacement impurity removal chamber 620. The fourth precipitation receiving tank 625 is located at the bottom of the first displacement impurity removal chamber 620. The fourth precipitation outlet 624 is located at the bottom of the first displacement impurity removal chamber 620 and is connected to the fourth precipitation receiving tank 625. The sixth heating and insulation layer 626 is used to heat and control the temperature of the entire first displacement impurity removal chamber 620.

[0317] As shown in Figures 12 and 14, the non-lithium active metal element extraction device 540 includes a seventh inlet 721, a seventh outlet 723, a non-lithium active metal element displacement extraction chamber 720, a second active metal plate 722, a fifth precipitation outlet 724, a fifth precipitation receiving tank 725, and a seventh heating and insulation layer 726. The second active metal plate 722 is located inside the non-lithium active metal element displacement extraction chamber 720. The fifth precipitation receiving tank 725 is located at the bottom of the non-lithium active metal element displacement extraction chamber 720. The fifth precipitation outlet 724 is located at the bottom of the non-lithium active metal element displacement extraction chamber 720 and is connected to the fifth precipitation receiving tank 725. The seventh heating and insulation layer 726 is used to heat and control the temperature of the entire non-lithium active metal element displacement extraction chamber 720.

[0318] As shown in Figures 12 and 14, the second impurity removal device 550 includes an eighth inlet 821, an eighth outlet 823, a second displacement impurity removal chamber 820, a third active metal plate 822, a sixth sedimentation outlet 824, a sixth sedimentation collection tank 825, and an eighth heating and insulation layer 826. The third active metal plate 822 is located inside the second displacement impurity removal chamber 820. The sixth sedimentation collection tank 825 is located at the bottom of the second displacement impurity removal chamber 820. The sixth sedimentation outlet 824 is located at the bottom of the second displacement impurity removal chamber 820 and is connected to the sixth sedimentation collection tank 825. The eighth heating and insulation layer 826 is used to heat and control the temperature of the entire second displacement impurity removal chamber 820.

[0319] As shown in Figures 12 and 14, the first discharge port 514 is connected to the second feed port 521, the second discharge port 524 is connected to the sixth feed port 621, the sixth discharge port 623 is connected to the seventh feed port 721, and the seventh discharge port 723 is connected to the eighth feed port 821.

[0320] In some embodiments of this application, the waste battery recycling device further includes a second metal element extraction device 560, which is connected to a second impurity removal device 550.

[0321] In some embodiments of this application, as shown in FIG11, the second metal element extraction device 560 includes a cooling crystallization device 960; the cooling crystallization device 960 includes a ninth inlet 961, a ninth outlet 962, a cooling crystallization chamber 967, a settling cone bottom 964, a settling outlet 965, a settling collection tank 966, and a ninth heating and insulation layer 963. The settling cone bottom 964 is located at the lower part of the settling collection tank 966, the settling collection tank 966 is located at the bottom of the cooling crystallization chamber 967, the settling outlet 965 is located at the bottom of the cooling crystallization chamber 967 and communicates with the settling collection tank 966, and the ninth heating and insulation layer 963 is used to heat and control the temperature of the entire cooling crystallization chamber 967.

[0322] In some embodiments of this application, as shown in FIG11, the second metal element extraction device 560 further includes a diversion pipe 939 and a diversion valve 938. One end of the diversion pipe 939 and the diversion valve 938 are located between the fifth discharge port 814 and the ninth inlet port 961, and the other end of the diversion pipe 939 is connected to the purification device 130. The diversion pipe 939 and the diversion valve 938 are not shown in the figure.

[0323] In some embodiments of this application, as shown in FIG11, the waste battery recycling device further includes a purification device 130 and a reflux device 140 connected sequentially in a direction away from the second metal element extraction device 560. The purification device 130 includes a third impurity removal chamber 570, a thirteenth inlet 571, an impurity removal system 572, a thirteenth outlet 573, and a thirteenth heating and insulation layer 574. In the purification device 130, the impurity removal system 572 is located inside the third impurity removal chamber 570. The thirteenth inlet 571 and the thirteenth outlet 573 are disposed on the side wall of the third impurity removal chamber 570. When the third impurity removal chamber 570 includes four side walls, the thirteenth inlet 571 and the thirteenth outlet 573 are opened on the opposite side walls of the third impurity removal chamber 570. When the side wall of the third impurity removal chamber 570 is a complete arc shape, the distance between the thirteenth inlet 571 and the thirteenth outlet 573 is approximately equal to the diameter of the arc. The purification device 130 is connected to the second metal element extraction device 560. Specifically, the thirteenth inlet 571 is connected to the other end of the diversion pipe 939 (not shown in the figure); the thirteenth inlet 571 is also connected to the ninth outlet 962. The reflux device 140 includes a reflux pump group 580 and a reflux pipe 590. The reflux device connects the purification device and the melting device. Specifically, the reflux pump group 580 is connected to the thirteenth outlet 573, one end of the reflux pipe 590 is connected to the reflux pump group 580, and the other end of the reflux pipe 590 is connected to the feed and return port 523, for refluxing the molten salt back to the melting reaction device 120.

[0324] In some embodiments of this application, as shown in Figures 12 and 13, the second metal element extraction device 560 includes an extraction extractor 930, a distillation extractor B 940, and a first dust collector 950 connected in sequence along a direction away from the second impurity removal device 550.

[0325] In some embodiments of this application, as shown in FIG12, the second metal element extraction device 560 further includes a diversion pipe 939 and a diversion valve 938. One end of the diversion pipe 939 and the diversion valve 938 are located between the eighth discharge port 823 and the tenth feed port 931. The other end of the diversion pipe is connected to the purification device 130, and the dryer 936 is connected to the diversion pipe 939.

[0326] In some embodiments of this application, as shown in FIG13, the second metal element extraction device 560 further includes a diversion pipe 939 and a diversion valve 938. One end of the diversion pipe 939 and the diversion valve 938 are located between the fifth discharge port 814 and the tenth feed port 931. The other end of the diversion pipe is connected to the purification device 130, and the dryer 936 is connected to the diversion pipe 939.

[0327] As shown in Figures 12 and 13, the extractor 930 includes a tenth inlet 931, a tenth outlet 933, a powder outlet 934, a tenth heating and insulation layer 935, a dryer 936, a solvent vapor pipe 937, a vapor reflux and replenishment inlet 932, and an extraction chamber 930A. As shown in Figures 12 and 13, the tenth inlet 931 and the tenth outlet 933 of the extractor 930 are located on the sidewalls of the extraction chamber 930A. When the extraction chamber 930A has four sidewalls, the tenth inlet 931 and the tenth outlet 933 are located on opposite sidewalls of the extraction chamber 930A. When the sidewalls of the extraction chamber 930A are entirely arc-shaped, the distance between the tenth inlet 931 and the tenth outlet 933 is approximately equal to the diameter of the arc. The powder outlet 934 is located at the bottom of the extraction chamber 930A and connected to the dryer 936. The vapor reflux and replenishment inlet 932 is located above the extraction chamber 930A. One end of the solvent vapor pipe 937 is connected to the vapor reflux and replenishment inlet 932, and the other end of the solvent vapor pipe 937 is connected to the dryer 936, so that the gaseous extractant evaporated from the dryer 936 can be returned to the extraction chamber 930A for reuse through the solvent vapor pipe 937. The insoluble solids discharged from the powder outlet 934 are dried by the dryer 936 and then discharged into the third impurity removal chamber 570 of the purification device 130 through the diversion pipe 939.

[0328] As shown in Figures 12 and 13, the distillation extractor B 940 includes an eleventh feed inlet 941, an eleventh discharge outlet 942, a first product outlet 943, a first product receiving tank 944, an eleventh heating and insulation layer 945, and a first distillation chamber 946. The eleventh feed inlet 941 and the eleventh discharge outlet 942 are located on the side walls of the first distillation chamber 946. When the first distillation chamber 946 has four side walls, the eleventh feed inlet 941 and the eleventh discharge outlet 942 are located on opposite side walls of the first distillation chamber 946. When the side walls of the first distillation chamber 946 are entirely circular arcs, the distance between the eleventh feed inlet 941 and the eleventh discharge outlet 942 is approximately equal to the diameter of the arc. The tenth discharge port 933 is connected to the eleventh feed port 941. The first product receiving tank 944 is located at the bottom of the first distillation chamber 946. The first product outlet 943 is located at the bottom of the first distillation chamber 946 and is connected to the first product receiving tank 944 for collecting products, such as LiCl.

[0329] As shown in Figures 12 and 13, the first dust collector 950 includes a first steam inlet 951, a first steam outlet 952, a first dust collection outlet 954, a first dust collection filter 953, a first fine powder collection tank 955, and a first dust collection chamber 956. The first steam inlet 951 and the first steam outlet 952 are located on the side walls of the first dust collection chamber 956. When the first dust collection chamber 956 has four side walls, the first steam inlet 951 and the first steam outlet 952 are located on opposite side walls of the first dust collection chamber 956. When the side walls of the first dust collection chamber 956 are entirely arc-shaped, the distance between the first steam inlet 951 and the first steam outlet 952 is approximately equal to the diameter of the arc. The eleventh discharge port 942 is connected to the first steam inlet 951. The first dust collection filter 953 is located inside the first dust collection chamber 956. The first fine powder collection tank 955 is located at the bottom of the first dust collection chamber 956. The first dust collection outlet 954 is located at the bottom of the first dust collection chamber 956 and is connected to the first fine powder collection tank 955. The first steam outlet 952 is connected to the steam return and replenishment inlet 932 through a pipe so that the gaseous extractant can be returned to the extraction chamber 930A for reuse.

[0330] In some embodiments of this application, as shown in Figures 12 and 13, the waste battery recycling device further includes a purification device 130 and a reflux device 140 connected sequentially in a direction away from the second metal element extraction device 560. The purification device 130 includes a third impurity removal chamber 570, a thirteenth inlet 571, an impurity removal system 572, a thirteenth outlet 573, and a thirteenth heating and insulation layer 574. The impurity removal system 572 is located inside the third impurity removal chamber 570. The purification device 130 is connected to the second metal element extraction device 560. Specifically, the thirteenth inlet 571 is connected to the other end of the diversion pipe 939. The reflux device 140 includes a reflux pump assembly 580 and a reflux pipeline 590. The reflux device 140 connects the purification device 130 and the melting device 120. Specifically, the reflux pump assembly 580 is connected to the thirteenth discharge port 573, one end of the reflux pipeline 590 is connected to the reflux pump assembly 580, and the other end of the reflux pipeline 590 is connected to the feed and return port 523, for returning the remaining molten salt to the melting reaction device 120 to continue serving as a medium. That is, in this process, the thirteenth feed port 571 of the purification device 130 is connected to the diversion pipeline 939 of the second metal element extraction device 560, and the reflux pump assembly 580 of the reflux device 140 is connected to the thirteenth discharge port 573 of the purification device 130 and the feed and return port 523 of the melting device 120, for returning the molten salt to the melting device 120 for recycling.

[0331] In some embodiments of this application, as shown in FIG14, the second metal element extraction device 560 includes a distillation extractor A910 and a second dust collector 920 connected in sequence in a direction away from the second impurity removal device 550.

[0332] As shown in Figure 14, the distillation extractor A910 includes a twelfth feed inlet 911, a twelfth discharge outlet 912, a second product outlet 913, a second product receiving tank 914, a twelfth heating and insulation layer 915, and a second distillation chamber 916. The twelfth feed inlet 911 and the twelfth discharge outlet 912 are located on the side walls of the second distillation chamber 916. When the second distillation chamber 916 has four side walls, the twelfth feed inlet 911 and the twelfth discharge outlet 912 are located on opposite side walls of the second distillation chamber 916. When the side walls of the second distillation chamber 916 are entirely arc-shaped, the distance between the twelfth feed inlet 911 and the twelfth discharge outlet 912 is approximately equal to the diameter of the arc. The twelfth feed inlet 911 and the eighth discharge outlet 823 are connected by a pipe. The second product receiving tank 914 is located at the bottom of the second distillation chamber 916. The second product outlet 913 is located at the bottom of the second distillation chamber 916 and is connected to the second product receiving tank 914.

[0333] As shown in Figure 14, the second dust collector 920 includes a second steam inlet 921, a second steam outlet 922, a second dust filter 923, a second dust outlet 924, a second fine powder collection tank 925, and a second dust collection chamber 926. The twelfth discharge port 912 is connected to the second steam inlet 921 via a pipe. The second dust filter 923 is located inside the second dust collection chamber 926. The second fine powder collection tank 925 is located at the bottom of the second dust collection chamber 926. The second dust outlet 924 is located at the bottom of the second dust collection chamber 926 and communicates with the second fine powder collection tank 925.

[0334] In some embodiments of this application, as shown in FIG14, the second metal element extraction device 560 further includes a diversion pipe 939 and a diversion valve 938. One end of the diversion pipe 939 and the diversion valve 938 are located between the eighth discharge port 823 and the twelfth inlet port 911. The other end of the diversion pipe 939 is connected to the purification device 130, and the second steam outlet 922 is connected to the diversion pipe 939 through a pipe.

[0335] In some embodiments of this application, as shown in FIG14, the waste battery recycling device further includes a purification device 130 and a reflux device 140 connected sequentially in a direction away from the second metal element extraction device 560. The purification device 130 includes a third impurity removal chamber 570, a thirteenth inlet 571, an impurity removal system 572, a thirteenth outlet 573, and a thirteenth heating and insulation layer 574. The impurity removal system 572 is located inside the third impurity removal chamber 570. The purification device 130 is connected to the second metal element extraction device 560. Specifically, the thirteenth inlet 571 is connected to the other end of the diversion pipe 939, and the second steam outlet 922 of the second dust collector 920 is connected to the diversion pipe 939 and connected to the purification device 130 through the diversion pipe 939. The reflux device 140 includes a reflux pump assembly 580 and a reflux pipeline 590. The reflux device 140 connects the purification device 130 and the melting device 120. Specifically, the reflux pump assembly 580 is connected to the thirteenth discharge port 573, one end of the reflux pipeline 590 is connected to the reflux pump assembly 580, and the other end of the reflux pipeline 590 is connected to the feed and return port 523, used to reflux the remaining molten salt back into the melting reaction device 120 to continue serving as a medium. That is, in this process, the purification device 130 is connected to the second metal element extraction device 560, and the reflux device 140 connects the purification device 130 and the melting device 120, used to reflux the molten salt back into the melting device 120.

[0336] In some embodiments of this application, the waste battery recycling device includes a pretreatment device 110, a melting device 120, a first impurity removal device 530, a non-lithium active metal element extraction device 540, a second impurity removal device 550, a second metal element extraction device 560, and a purification device 130 and a reflux device 140 connected in sequence in a direction away from the second metal element extraction device 560. The first impurity removal device 530 includes a third inlet 611, a third outlet 614, a first electrolytic impurity removal chamber 610, a first anode inert electrode plate 612, a first cathode inert electrode plate 613, a first precipitation collection tank 616, a first precipitation outlet 615, and a third heating and insulation layer 617. The non-lithium active metal element extraction device 540 includes a fourth inlet 711, a fourth outlet 714, a non-lithium active metal element electrolytic extraction chamber 710, a second anode inert electrode plate 712, a second cathode inert electrode plate 713, a second precipitation collection tank 716, a second precipitation outlet 715, and a fourth heating and insulation layer 717. The second impurity removal device 550 includes a fifth inlet 811, a fifth outlet 814, a second electrolytic impurity removal chamber 810, a third anode inert electrode plate 812, a third cathode inert electrode plate 813, a third precipitation collection tank 816, a third precipitation outlet 815, and a fifth heating and insulation layer 817. The second metal element extraction device 560 includes a distillation extractor A910 and a second dust collector 920 connected sequentially in a direction away from the second impurity removal device 550; the second metal element extraction device 560 also includes a diversion pipe 939 and a diversion valve 938, one end of the diversion pipe 939 and the diversion valve 938 being located between the fifth discharge port 814 and the twelfth feed port 911. The other end of the diversion pipe 939 is connected to the purification device 130.

[0337] The aforementioned device enables the stepwise extraction of impurities, non-lithium active metal elements, lithium, or sodium from waste battery cathode materials, simplifying the recycling process and improving recycling efficiency. This application does not impose any particular limitation on the form of the aforementioned "connection," and any connection form known in the art can be used, as long as it achieves the purpose of this application. For example, the aforementioned "connection" can be a pipe connection.

[0338] The following is a brief description of the specific implementation method of the waste battery recycling method of this application, based on the apparatus shown in Figures 11 to 14.

[0339] (1) The waste battery positive electrode material obtained from the treatment is fed into the pretreatment chamber 510 shown in Figures 11 to 14 through the first feed port 511. According to the actual waste battery positive electrode material to be treated, chlorinating agent, sulfur source, reducing agent and oxidizing agent are also fed into the first feed port 511. By controlling the magnetic separation crushing mixer 512 and the first heating and heat preservation layer 515, a solid mixture is obtained. After being screened by the screen 513, it is discharged from the first discharge port 514, thus completing the process of converting the waste battery positive electrode material into a solid mixture.

[0340] (2) The obtained solid mixture is fed into the melting chamber 520 as shown in Figures 11 to 14 through the second feed port 521. Molten salt is fed into the melting chamber 520 through the feed and return port 523. The melting conditions are controlled by the stirrer 522 and the second heating and insulation layer 525. The solid mixture and molten salt are mixed to form a molten salt bath, which is then discharged through the second discharge port 524.

[0341] (3) The molten salt bath enters the first impurity removal device 530, the non-lithium active metal element extraction device 540 and the second impurity removal device 550 as shown in Figures 11 to 14 in sequence to extract the non-lithium active metal elements.

[0342] ① Non-lithium active metal elements can be extracted using electrolysis.

[0343] First impurity removal stage: The molten salt bath enters the first impurity removal device 530 as shown in Figures 11 and 13. The molten salt bath enters the first electrolytic de-impurity removal chamber 610 through the third feed port 611. The temperature of the first electrolytic de-impurity removal chamber 610 is controlled by the third heating and insulation layer 617. Impurity a is generated under the electrolytic action of the first anode inert electrode plate 612 and the first cathode inert electrode plate 613. Impurity a settles in the first electrolytic de-impurity removal chamber 610 to the first precipitation outlet 615 and is collected by the first precipitation collection tank 616. The remaining molten salt bath, i.e., the first melt, is discharged from the third discharge port 614.

[0344] Non-lithium active metal element extraction stage: The first molten liquid after the first impurity removal stage enters the non-lithium active metal element extraction device 540 as shown in Figures 11 and 13. The first molten liquid enters the non-lithium active metal element electrolytic extraction chamber 710 through the fourth feed port 711. The temperature of the non-lithium active metal element electrolytic extraction chamber 710 is controlled by the fourth heating and heat preservation layer 717. Under the electrolytic action of the second anode inert electrode plate 712 and the second cathode inert electrode plate 713, non-lithium active metals nickel and / or cobalt are generated. The non-lithium active metals settle in the non-lithium active metal element electrolytic extraction chamber 710 to the second precipitation outlet 715 and are collected by the second precipitation collection tank 716. The remaining molten salt bath, i.e., the second molten liquid, is discharged from the fourth discharge port 714.

[0345] The second impurity removal stage: The second molten liquid, after the non-lithium active metal element extraction stage, enters the second impurity removal device 550 as shown in Figures 11 and 13. The second molten liquid enters the second electrolytic de-impurity chamber 810 through the fifth feed port 811. The temperature of the second electrolytic de-impurity chamber 810 is controlled by the fifth heating and insulation layer 817. Under the electrolytic action of the third anode inert electrode plate 812 and the third cathode inert electrode plate 813, impurity b is generated. Impurity b settles in the second electrolytic de-impurity chamber 810 to the third precipitation outlet 815 and is collected by the third precipitation collection tank 816. The remaining molten salt bath, i.e., the third molten liquid, is discharged through the fifth discharge port 814. If the positive electrode material of the waste battery contains manganese, metallic manganese is also electrolyzed in this stage.

[0346] ②Non-lithium active metal elements can be extracted using a displacement process.

[0347] First impurity removal stage: The molten salt bath enters the first impurity removal device 530 as shown in Figures 12 and 14. The molten salt bath enters the first displacement impurity removal chamber 620 through the sixth feed port 621. The temperature of the first displacement impurity removal chamber 620 is controlled by the sixth heating and insulation layer 626, so that the molten salt bath and the first active metal plate 622 undergo a displacement reaction, displacing impurity a. Impurity a settles in the first displacement impurity removal chamber 620 to the fourth precipitation outlet 624 and is collected by the fourth precipitation collection tank 625. The remaining molten salt bath, i.e., the first melt, is discharged from the sixth discharge port 623.

[0348] Non-lithium active metal element extraction stage: The first melt, after the first impurity removal stage, enters the non-lithium active metal element extraction device 540 as shown in Figures 12 and 14. The first melt enters the non-lithium active metal element displacement extraction chamber 720 through the seventh feed port 721. The temperature of the non-lithium active metal element displacement extraction chamber 720 is controlled by the seventh heating and insulation layer 726, causing the first melt to undergo a displacement reaction with the second active metal plate 722, displacing non-lithium active metals nickel and / or cobalt. The non-lithium active metals settle in the non-lithium active metal element displacement extraction chamber 720 to the fifth precipitation outlet 724 and are collected by the fifth precipitation collection tank 725. The remaining molten salt bath, i.e., the second melt, is discharged through the seventh discharge port 723.

[0349] The second impurity removal stage: After the non-lithium active metal element extraction stage, the second molten liquid enters the second impurity removal device 550 as shown in Figures 12 and 14. The second molten liquid enters the second displacement impurity removal chamber 820 through the eighth feed port 821. The temperature of the second displacement impurity removal chamber 820 is controlled by the eighth heating and insulation layer 826, causing the second molten liquid to undergo a displacement reaction with the third active metal plate 822, displacing impurity b. Impurity b settles in the second displacement impurity removal chamber 820 to the sixth precipitation outlet 824 and is collected by the sixth precipitation collection tank 825. The remaining molten salt bath, i.e., the third molten liquid, is discharged through the eighth discharge port 823. If the waste battery positive electrode material contains manganese, metallic manganese is also displaced in this stage.

[0350] (4) The third melt after the second impurity removal stage enters the second metal element extraction device 560 as shown in Figures 11 to 14.

[0351] ①The initial waste battery cathode material does not contain lithium or sodium elements, and the third melt directly enters the purification device 130 through the diversion pipe 939.

[0352] ② The initial cathode material added from the waste battery contains lithium or sodium. Depending on the type of waste battery and the type of molten salt used, the extraction of the second metal element varies. The following examples are for illustrative purposes only:

[0353] i) When the positive electrode material in a lithium battery is combined with a molten salt that does not contain lithium, lithium can be extracted using the extraction + distillation process B.

[0354] For example, when the cathode material in a lithium battery is combined with molten salt NaAlCl4 or KAlCl4, as shown in Figure 12, the third molten liquid discharged through the eighth outlet 823 enters the extraction extractor 930 entirely through the diversion valve 938. Distillation is generally not used for process A because the NaAlCl4 or KAlCl4 in the third molten liquid discharged through the eighth outlet 823 will decompose into NaCl or KCl at high temperatures, making it difficult to separate from LiCl.

[0355] For example, when the positive electrode material in a lithium battery is combined with molten salt NaCl and / or KCl, the molten salt may also include other non-lithium molten salts, as shown in Figures 12 and 13. The third melt discharged through the fifth outlet 814 or the eighth outlet 823 enters the extraction extractor 930 through the diversion valve 938.

[0356] ii) When the cathode material in a lithium battery is combined with molten salt LiAlCl4, or when the cathode material is combined with molten salt LiAlCl4 and LiCl, lithium can be extracted by direct distillation process A, as shown in Figure 14. The third molten liquid discharged through the eighth outlet 823 is divided by the diversion valve 938. Part of it enters the third impurity removal chamber 570 through the diversion pipe 939, and the other part enters the lithium extraction distillation unit 910. The diversion flow rate is determined according to the Li element content in the cathode material.

[0357] iii) When the cathode material in a lithium battery is combined with molten salts LiCl and / or LiAlCl4, and optionally lithium-free molten salts, lithium can be extracted using extraction + distillation method B. As shown in Figures 12 and 13, the third molten liquid discharged through the eighth outlet 823 or the fifth outlet 814 is diverted by the diversion valve 938. Part of it enters the third impurity removal chamber 570 through the diversion pipe 939, and the other part enters the extraction extractor 930. The diversion flow rate is determined based on the Li content in the cathode material.

[0358] iv) When the cathode material in a lithium battery is combined with KCl molten salt, or when the cathode material is combined with LiCl and KCl molten salt, lithium can be extracted by cooling crystallization. As shown in Figure 11, the third molten liquid discharged through the fifth outlet 814 all enters the cooling crystallization device 960.

[0359] (v) When the cathode material in a sodium battery is combined with molten salt NaAlCl4, or when the cathode material is combined with molten salt NaAlCl4 and NaCl, sodium can be extracted using direct distillation process A, as shown in Figure 14. The third molten liquid discharged from the eighth outlet 823 is diverted by the diversion valve 938. Part of it enters the third impurity removal chamber 570 through the diversion pipeline 939, and the other part enters the lithium extraction distillation unit 910. The diversion flow rate is determined according to the Na element content in the cathode material. During high-temperature distillation, NaAlCl4 decomposes into NaCl and gaseous AlCl3. The NaCl generated during the pretreatment chlorination process and the NaCl decomposed from NaAlCl4 precipitate into the second product collection tank 914.

[0360] (vi) When the positive electrode material in a sodium battery is combined with KCl molten salt, or when the positive electrode material is combined with NaCl and KCl molten salt, sodium can be extracted by cooling crystallization. As shown in Figure 11, the third molten liquid discharged through the fifth outlet 814 all enters the cooling crystallization device 960.

[0361] The following describes some possible implementation methods.

[0362] Method 1: Cooling Crystallization Extraction Process: As shown in Figure 11, in the second metal element extraction device 560, the third molten liquid flows into the cooling crystallization device 960 and / or the diversion pipeline 939 through the diversion valve 938, based on the content of the second metal element in the battery cathode material initially added to the pretreatment chamber 510 and the LiCl or NaCl content in the molten salt. Some possible scenarios are described below:

[0363] Scenario 1: When using lithium-containing waste battery cathode material and KCl as the molten salt, no diversion is required. The third melt enters the cooling crystallization device 960 through the ninth inlet 961 with ceramic fine filter (not shown in the figure). After the second metal element is extracted, it is discharged to the third impurity removal chamber 570 through the ninth outlet 962 with ceramic fine filter (not shown in the figure). In the cooling crystallization chamber 967, the crystallization temperature is controlled by the ninth heating insulation layer 963 (maintained at 345℃~360℃, for example, around 350℃). LiCl precipitates at the bottom of the settling cone 964 and is discharged to the settling collection tank 966 through the settling outlet 965.

[0364] Scenario 2: When using waste battery cathode material containing sodium and the molten salt is KCl, no diversion is required. The third melt enters the cooling crystallization device 960 through the ninth inlet 961 with ceramic fine filter (not shown in the figure). After the second metal element is extracted, it is discharged to the third impurity removal chamber 570 through the ninth outlet 962 with ceramic fine filter (not shown in the figure). In the cooling crystallization chamber 967, the crystallization temperature (e.g., 420℃~500℃) is controlled by the ninth heating insulation layer 963. NaCl precipitates at the bottom of the settling cone 964 and is discharged to the settling collection tank 966 through the settling outlet 965.

[0365] Scenario 3: When using waste battery cathode material containing lithium and the molten salt is LiCl and KCl, it is necessary to divert the flow. That is, the flow is diverted through the diversion valve 938. The third melt used for lithium extraction enters the cooling crystallization device 960, and the third melt not used for lithium extraction enters the third impurity removal chamber 570 through the diversion pipe 939.

[0366] Scenario 4: When using waste battery cathode material containing sodium and the molten salt is NaCl and KCl, it is necessary to divide the flow. That is, the flow is divided through the diversion valve 938. The third melt used for sodium extraction enters the cooling crystallization device 960, and the third melt not used for sodium extraction enters the third impurity removal chamber 570 through the diversion pipeline 939.

[0367] Method 2: Extraction + Distillation Process B: As shown in Figures 12 and 13, in the second metal element extraction device 560, the third molten liquid flows into the extraction unit 930 and / or the diversion pipeline 939 through the diversion valve 938, controlling the amount of the third molten liquid flowing into the extraction unit 930 and / or the diversion pipeline 939 based on the lithium content in the battery cathode material initially added to the pretreatment chamber 510 and the LiCl or LiAlCl4 content in the molten salt. Some possible scenarios are described below:

[0368] Scenario 1: When using lithium-containing waste battery cathode material and the molten salt contains LiCl and / or LiAlCl4, and optionally other molten salts (such as NaCl, KCl, etc.), it is necessary to split the flow. That is, the flow is split through the split valve 938. The third molten liquid used for lithium extraction enters the extraction extractor 930, and the third molten liquid not used for lithium extraction enters the third impurity removal chamber 570 through the split pipeline 939.

[0369] Scenario 2: When using lithium-containing waste battery cathode material and the molten salt does not contain LiCl or LiAlCl4 (for example, using KAlCl4 or NaCl+KCl as the molten salt), no diversion is required. That is, the third molten liquid is completely introduced into the extraction extractor 930 through the diversion valve 938 to extract lithium.

[0370] In one possible implementation, when lithium-containing waste battery cathode material is used and the molten salt contains LiCl and / or LiAlCl4, after being diverted by the diversion valve 938, the third molten liquid not used for lithium extraction enters the third impurity removal chamber 570 through the diversion pipe 939; the third molten liquid used for lithium extraction is cooled and crushed into powder through the tenth feed inlet 931 with cooling and crushing facilities (not shown in the figure), and enters the extraction extractor 930, where the temperature of the extraction chamber 930A is controlled by the tenth heating and insulation layer 935; the LiCl in the powder... The powder is dissolved and extracted by a solvent, including but not limited to one or more of water, acetone, cyclohexanone, methanol, ethanol, isopropanol, and diethyl ether. The remaining undissolved powder is discharged from the powder outlet 934, dried by the dryer 936, and then enters the third impurity removal chamber 570. The solvent mixed in with the undissolved powder is evaporated in the dryer 936 and returned to the extractor 930 through the solvent vapor pipe 937. The lithium-ion-containing extract is discharged from the tenth outlet 933 with a ceramic fine filter (not shown in the figure) and enters the lithium distillation extractor B through the eleventh inlet 941. In 940, the temperature of the first distillation chamber 946 is controlled by the eleventh heating and insulation layer 945 to achieve solvent vaporization; the vapor is discharged from the eleventh discharge port 942 and enters the first dust collector 950 through the first steam inlet 951, is filtered by the first dust collector filter 953, and after purification, the vapor is discharged from the first steam outlet 952 and returned to the extractor 930 through the steam reflux and replenishment inlet 932; in the lithium distillation extractor B 940, the LiCl powder obtained by solvent evaporation is discharged to the first product collection tank 944 through the first product outlet 943; in the first dust collector 950, the filtered dust is discharged to the first fine powder collection tank 955 through the first dust collection outlet 954.

[0371] Method 3: Direct Distillation Process A: As shown in Figure 14, in the second metal element extraction device 560, the third molten liquid flows into the lithium distillation extractor A910 and the diversion pipe 939 through the diversion valve 938. The amount of the third molten liquid flowing into the distillation lithium extractor A910 and the diversion pipe 939 is controlled according to the content of the second metal element in the battery cathode material initially added to the pretreatment chamber 510 and the content of LiAlCl4 or NaAlCl4 in the molten salt. Some possible scenarios are described below:

[0372] Scenario 1: When using lithium-containing waste battery cathode material and the molten salt contains LiAlCl4, the third molten liquid used for lithium distillation is diverted through the diversion valve 938 into the lithium distillation extractor A910, while the third molten liquid not used for lithium distillation enters the third impurity removal chamber 570 through the diversion pipe 939.

[0373] Scenario 2: When using waste battery cathode material containing sodium and the molten salt contains NaAlCl4, the flow is diverted through the diversion valve 938; the third molten liquid used for sodium distillation enters the lithium distillation extractor A910, and the molten salt bath not used for sodium distillation enters the third impurity removal chamber 570 through the diversion pipe 939.

[0374] In one possible implementation, when using lithium-containing waste battery cathode material and LiAlCl4 as the molten salt, after being diverted by the diversion valve 938, the third molten liquid not used for lithium extraction enters the third impurity removal chamber 570 through the diversion pipe 939; the third molten liquid used for lithium extraction enters the lithium distillation extractor A910 through the twelfth feed port 911, and the temperature of the second distillation chamber 916 is controlled by the twelfth heating and insulation layer 915, thereby achieving the evaporation of AlCl3 in the third molten liquid (LiAlCl4 decomposes into LiCl and Al). AlCl3 vapor is discharged from the twelfth outlet 912 and enters the dust collector 920 through the second steam inlet 921. After being filtered by the second dust collector filter 923, the vapor is discharged from the second steam outlet 922 and enters the third impurity removal chamber 570. In the lithium distillation extractor A910, the solid lithium salt left after AlCl3 evaporation is discharged to the second product collection tank 914 through the second product outlet 913. In the dust collector 920, the filtered dust is discharged to the second fine powder collection tank 925 through the second dust collection outlet 924.

[0375] (5) The third molten liquid extracted by the second metal element enters the purification device 130 as shown in Figures 11 to 14. The third molten liquid enters the third impurity removal chamber 570 through the thirteenth feed port 571 of the purification device. The temperature of the third impurity removal chamber 570 is controlled by the thirteenth heating and insulation layer 574. Under the action of the impurity removal system 572, by-products, impurities, etc. are removed, and the liquid is discharged to the reflux pump group 580 through the thirteenth discharge port 573.

[0376] (6) The third melt that passes through the third impurity removal chamber 570 enters the reflux pump group 580 shown in Figures 11 to 14, and then returns to the melting chamber 520 through the reflux pipeline 590 via the feeding and return port 523.

[0377] In summary, the waste battery recycling method provided in this application is based on a molten salt system and employs methods such as displacement or electrolysis, cooling crystallization, extraction treatment, and distillation treatment B and distillation treatment A to extract high-value metal elements from waste batteries. This provides a low-cost, efficient, and environmentally friendly method and related apparatus for extracting and recovering metal elements from waste batteries.

[0378] Example

[0379] The embodiments and comparative examples provided below illustrate the implementation of this application in more detail. Various tests and evaluations were conducted according to the methods described below. Furthermore, unless otherwise specified, "parts" and "%" are quality standards.

[0380] Test methods and equipment:

[0381] Element content test:

[0382] Inductively Coupled Plasma (ICP) Testing

[0383] The content of high-value metal elements extracted was determined using ICP testing.

[0384] The methods used in this application are conventional testing methods in the art, and those skilled in the art can choose appropriate testing methods as needed. This application does not impose any limitations.

[0385] Calculation of non-lithium active metal recovery rate:

[0386] The content of a non-lithium active metal element to be extracted from the cathode material of the waste battery is determined by ICP testing and recorded as C1, in mg / kg. The mass of the waste battery cathode material is weighed using a balance and recorded as M1. The content of the non-lithium active metal obtained by displacement is determined by ICP testing and recorded as C2, in mg / kg. The mass of the extracted non-lithium active metal is weighed using a balance and recorded as M2. The recovery rate is calculated as M2×C2 / (M1×C1)×100%.

[0387] The aforementioned non-lithium active metals are nickel, cobalt, and manganese.

[0388] Calculation of lithium or sodium recovery rate:

[0389] The lithium or sodium content to be extracted from the cathode material of the waste battery is determined by ICP testing and recorded as C1', in mg / kg. The mass of the waste battery cathode material is weighed using a balance and recorded as M1. The lithium or sodium content in LiCl or NaCl obtained by ICP testing is recorded as C2', in mg / kg. The mass of the extracted LiCl or NaCl is weighed using a balance and recorded as M2'. The recovery rate is calculated as M2'×C2' / (M1×C1')×100%.

[0390] Example 1-1

[0391] <Preprocessing Stage>

[0392] Twenty used 18650 lithium cobalt oxide (LCO) batteries were soaked in brine to release their remaining charge. The batteries were then disassembled, and the positive electrode current collector and positive electrode material layer were separated. The positive electrode material layer was crushed and sieved to obtain the positive electrode material. The material contained 54.79 wt% Co, 6.45 wt% Li, 8.5% Cu impurities, and 0.05% Zn impurities. The used lithium cobalt oxide battery positive electrode material was fed into the pretreatment chamber 510 through the first inlet 511 (shown in Figure 5). A magnetic separator crusher / mixer 512 was used for crushing at 100 rpm. The material was then heated to 800°C and held for 3 hours through the first heating and insulation layer 515 to eliminate combustible impurities. It was then sieved through a 60-mesh screen 513 to obtain a solid mixture. After sieving through the screen 513, the solid mixture was fed into the melting chamber 520 through the first outlet 514 at a rate of 60 g / h, with 100 g of solid mixture being introduced at a time.

[0393] <Chlorination Reaction Stage>

[0394] In the melting chamber 520 shown in Figure 5, the temperature T2 of the melting chamber 520 is maintained at 350°C by the second heating and insulation layer 525. 500g of LiAlCl4 (mass ratio of solid mixture to molten salt 1:5) is added through the feeding and return port 523 to carry out the chlorination reaction. The stirring speed of the stirrer 522 is 150rpm to form a molten salt bath, which flows out through the second discharge port 524 at a rate of 60g / h into the first displacement and impurity removal chamber 620.

[0395] The chlorination reaction process is as follows: LiCoO2 + LiAlCl4 = LiAlO2 + LiCl + CoCl2 + 1 / 2Cl2

[0396] <First stage of impurity removal>

[0397] In the first displacement impurity removal chamber 620 shown in Figure 5, the molten salt bath enters through the third feed port 621 at a rate of 60 g / h. The temperature T3 of the first displacement impurity removal chamber 620 is controlled at 350℃ by the third heating and insulation layer 626. The copper ions in the molten salt bath react with the cobalt plate of the first active metal plate 622 to form metallic copper powder, i.e., impurity a. The residence time t3 of the molten salt bath in the first displacement impurity removal chamber is controlled to be 4 h, thereby controlling the impurity removal rate. The copper powder settles at the bottom of the precipitation cone to the first precipitation outlet 624 and is collected by the first precipitation collection tank 625. The remaining molten salt bath, i.e. the first melt, is discharged from the third discharge port 623 to the non-lithium active metal element displacement extraction chamber 720.

[0398] The displacement purification reaction process in the first purification stage is as follows: CuCl2 + Co = CoCl2 + Cu

[0399] <Extraction stage of non-lithium active metal elements>

[0400] After the first impurity removal stage, the first molten liquid enters the non-lithium active metal element replacement extraction chamber 720 (as shown in Figure 5) at a rate of 60 g / h through the fourth feed port 721. The temperature T4 of the non-lithium active metal element replacement extraction chamber 720 is controlled at 350℃ by the fourth heating and insulation layer 726. The cobalt ions in the first molten liquid undergo a replacement reaction with the second active metal plate 722 (Zn plate) for a reaction time of 2 h, generating metallic cobalt powder which settles at the bottom of the precipitation cone to the second precipitation outlet 724 and is finally collected by the second precipitation collection tank 725. The remaining molten salt bath, i.e., the second molten liquid, is discharged to the second impurity removal device 550 through the fourth discharge port 723. The net cobalt production capacity is 32.4 g / h.

[0401] The substitution and extraction reaction process for cobalt is as follows: CoCl2 + 2Zn = ZnCl2 + Co

[0402] <Second stage of impurity removal>

[0403] The second melt, after non-lithium active metal element extraction, enters the second displacement and impurity removal chamber 820 through the fifth feed port 821 as shown in Figure 5 at a rate of 60 g / h. The temperature T5 of the second displacement and impurity removal chamber is controlled at 350℃ by the fifth heating and insulation layer 826. Zinc ions in the second melt, i.e. impurity b, undergo a displacement reaction with the aluminum plate of the third active metal plate 822. The reaction time t5 is 4 h, and the generated zinc powder settles at the bottom of the precipitation cone to the third precipitation outlet 824. Finally, it is collected by the third precipitation collection tank 825. The remaining molten salt bath, i.e. the third melt, is discharged to the second metal element extraction device 560 through the fifth discharge port 823.

[0404] The displacement impurity removal reaction process in the second stage is as follows: 3ZnCl2 + 2Al = 2AlCl3 + 3Zn

[0405] <Second Metal Element Extraction Stage>

[0406] The third melt (mainly including LiCl, LiAlCl4, LiAlO2, and AlCl3) discharged from the second impurity removal stage enters the second metal element extraction device 560 as shown in Figure 5 at a rate of 60 g / h. It is diverted by the diversion valve 938 to control the amount of the third melt flowing into the lithium distillation extractor A910 and the diversion pipeline 939. The third melt not used for lithium extraction enters the third impurity removal chamber 570 through the diversion pipeline 939 at a flow rate of 3 g / h. The third melt used for lithium extraction enters the lithium distillation extractor A910 through the eighth feed port 911 at a flow rate of 57 g / h. The temperature T6 is controlled at 500℃ by the eighth heating and insulation layer 915, which causes the flux AlCl3 in the third melt to evaporate and the AlCl3 obtained by the decomposition of LiAlCl4. The vapor of the evaporated AlCl3 is discharged from the eighth discharge port 912 and enters the second dust collector 920 through the second steam inlet 921 (collecting a small amount of solid LiCl carried in the AlCl3 vapor). After filtration, the vapor is discharged from the second steam outlet 922 and enters the third impurity removal chamber 570. In the lithium distillation extractor A910, the solid lithium salt LiCl (which also contains a small amount of oxide LiAlO2) left after the flux evaporates is discharged to the second product collection tank 914 via the second product outlet 913; in the second dust collector 920, the solid LiCl obtained by filtering through the second dust collector filter 923 is discharged to the second fine powder collection tank 925 via the second dust collector outlet 924.

[0407] The material discharged through the second steam outlet 922 (mainly AlCl3) and the third molten liquid in the diversion pipe 939 enter the third impurity removal chamber 570 at a rate of 60 g / h through the ninth feed inlet 571. The temperature of the third impurity removal chamber is controlled at 350℃ by the ninth heating and insulation layer 574. Under the action of the impurity removal system 572, by-products and impurities (including LiAlO2 in the third molten liquid in the diversion pipe 939) are removed and collected, and discharged to the reflux pump group 580 through the ninth discharge outlet 573. The purified third molten liquid is then returned to the melting chamber 520 through the reflux pump group 580 and the reflux pipe 590 via the feed and return inlet 523, realizing the recycling of molten salt.

[0408] Based on the cobalt and lithium content in the initial materials, the recovery rates of cobalt and lithium chloride were 98.6% and 99.1%, respectively.

[0409] Examples 1-2

[0410] <Preprocessing Stage>

[0411] Twenty discarded 18650 sodium batteries (positive electrode NaNiO2) were soaked in brine to release their remaining charge. The batteries were then disassembled, and the positive electrode current collector and positive electrode material layer were separated. The positive electrode material layer was crushed and sieved to obtain the positive electrode material. The material contained 18.7 wt% Na, 47.14 wt% Ni, 2.1% Cu, and 1.8% Al. The discarded sodium battery positive electrode material was fed through the first inlet 511 (Figure 5), and the temperature of the first heating and insulation layer 515 was set to 800°C and held for 3 hours to eliminate combustible impurities. A magnetic separator crusher / mixer 512 was used for crushing at 100 rpm. The mixture was then sieved through a 60-mesh screen 513 to obtain a solid mixture. After sieving through screen 513, the solid mixture was fed into the melting chamber 520 through the first outlet 514 at a rate of 60 g / h, with 50 g of solid mixture introduced at a time.

[0412] <Chlorination Reaction Stage>

[0413] In the melting chamber 520 shown in Figure 5, the temperature T2 of the melting chamber 520 is maintained at 350℃ by the second heating and insulation layer 525. 500g of NaAlCl4 (mass ratio of solid mixture to molten salt 1:10) is added through the feeding and return port 523 to carry out the chlorination reaction. The stirring speed of the stirrer 522 is 150rpm, and the mixture forms a molten salt bath. The molten salt bath flows out through the second discharge port 524 at a rate of 60g / h into the first displacement and impurity removal chamber 620.

[0414] The chlorination reaction process is as follows: NaNiO2 + NaAlCl4 = NaAlO2 + NaCl + NiCl2 + 1 / 2Cl2

[0415] <First stage of impurity removal>

[0416] In the first displacement impurity removal chamber 620 shown in Figure 5, the molten salt bath enters through the third feed port 621 at a rate of 60 g / h. The temperature T3 of the first displacement impurity removal chamber 620 is controlled at 350℃ by the third heating and insulation layer 626. The copper ions in the molten salt bath react with the nickel plate of the first active metal plate 622 to form metallic copper powder, i.e., impurity a. The residence time t3 of the molten salt bath in the first displacement impurity removal chamber is controlled to be 5 h, thereby controlling the impurity removal rate. The copper powder settles at the bottom of the precipitation cone to the first precipitation outlet 624 and is collected by the first precipitation collection tank 625. The remaining molten salt bath, i.e. the first melt, is discharged from the third discharge port 623 to the non-lithium active metal element displacement extraction chamber 720.

[0417] The first impurity removal stage, the displacement impurity removal reaction process, is as follows: CuCl2 + Ni = NiCl2 + Cu

[0418] <Extraction stage of non-lithium active metal elements>

[0419] After the first impurity removal stage, the first molten liquid enters the non-lithium active metal element replacement extraction chamber 720 (as shown in Figure 5) at a rate of 60 g / h through the fourth feed port 721. The temperature T4 of the non-lithium active metal element replacement extraction chamber 720 is controlled at 350℃ by the fourth heating and insulation layer 726. The cobalt ions in the first molten liquid undergo a replacement reaction with the second active metal plate 722 (Zn plate) for a reaction time of 3 h, generating metallic nickel powder which settles at the bottom of the precipitation cone to the second precipitation outlet 724 and is finally collected by the second precipitation collection tank 725. The remaining molten salt bath, i.e., the second molten liquid, is discharged from the fourth discharge port 723 to the second impurity removal device 550. The net nickel production capacity is 32.4 g / h.

[0420] The nickel displacement extraction reaction process is as follows: NiCl2 + 2Zn = ZnCl2 + Ni

[0421] <Second stage of impurity removal>

[0422] The second melt, after non-lithium active metal element extraction, enters the second displacement and impurity removal chamber 820 through the fifth feed port 821 as shown in Figure 5 at a rate of 60 g / h. The temperature T5 of the second displacement and impurity removal chamber is controlled at 350℃ by the fifth heating and insulation layer 826. Zinc ions in the second melt, i.e. impurity b, undergo a displacement reaction with the aluminum plate of the third active metal plate 822. The reaction time t5 is 5 h, and the generated zinc powder settles at the bottom of the precipitation cone to the third precipitation outlet 824. Finally, it is collected by the third precipitation collection tank 825. The remaining molten salt bath, i.e. the third melt, is discharged to the second metal element extraction device 560 through the fifth discharge port 823.

[0423] The displacement impurity removal reaction process in the second stage is as follows: 3ZnCl2 + 2Al = 2AlCl3 + 3Zn

[0424] <Second Metal Element Extraction Stage>

[0425] The third melt (mainly including NaCl, NaAlCl4, LiAlO2, and AlCl3) discharged from the second impurity removal stage enters the second metal element extraction device 560 shown in Figure 5 at a rate of 60 g / h. The sodium extraction process is the same as the lithium extraction process in Example 1-1, except that the extracted element is changed from lithium to sodium.

[0426] The third melt (mainly AlCl3) after sodium extraction and the third melt in the diversion pipe 939 enter the third impurity removal chamber 570 at a rate of 60 g / h through the ninth feed port 571. The temperature of the third impurity removal chamber is controlled at 350℃ by the ninth heating and insulation layer 574. Under the action of the impurity removal system 572, by-products and impurities (such as NaAlO2) are removed and collected, and discharged to the reflux pump group 580 through the ninth discharge port 573.

[0427] After purification, the third melt is returned to the melting chamber 520 via the reflux pump group 580 and then through the reflux pipeline 590 and the feed and return port 523, thus realizing the recycling of molten salt.

[0428] Based on the nickel content in the initial material, the nickel recovery rate was 98.99%.

[0429] Examples 1-3

[0430] <Preprocessing Stage>

[0431] Twenty used 18650 ternary (NCM523) batteries were soaked in brine to release their remaining charge. The batteries were then disassembled, and the positive electrode current collector and positive electrode material layer were separated. The positive electrode material layer was crushed and sieved to obtain the positive electrode material. The material contained 27.39 wt% Ni, 10.96 wt% Co, 14.83 wt% Mn, 6.45 wt% Li, 2.1% Cu, and 1.8% Al. The used NCM523 battery positive electrode material was fed into a pretreatment chamber 510 through the first feed inlet 511 shown in Figure 4. A magnetic separator crusher / mixer 512 was used for crushing at 100 rpm. The material was then heated to 800°C and held for 3 hours through a first heating and insulation layer 515 to eliminate flammable impurities. Finally, it was sieved through a 60-mesh screen 513 to obtain a solid mixture. After being screened by screen 513, the solid mixture enters the melting chamber 520 from the first discharge port 514 at a rate of 60g / h, with 50g of solid mixture being introduced.

[0432] <Chlorination Reaction Stage>

[0433] In the melting chamber 520 shown in Figure 4, the temperature T2 of the melting chamber 520 is maintained at 550℃ by the second heating and insulation layer 525. 500g of NaAlCl4 (mass ratio of solid mixture to molten salt 1:10) is added through the feeding and return port 523 to carry out the chlorination reaction. The stirring speed of the stirrer 522 is 150rpm, and the mixture forms a molten salt bath. The molten salt bath flows out through the second discharge port 524 at a rate of 60g / h into the first displacement and impurity removal chamber 620.

[0434] The chlorination reaction process is as follows: 2LiNi 0.5 Co 0.2 Mn 0.3 O2+2NaAlCl4=2NaAlO2+2LiCl+NiCl2+0.4CoCl2+0.6MnCl2+Cl2

[0435] <First stage of impurity removal>

[0436] In the first displacement impurity removal chamber 620 shown in Figure 4, the molten salt bath enters through the third feed port 621 at a rate of 60 g / h. The temperature T3 of the first displacement impurity removal chamber 620 is controlled at 350℃ by the third heating and insulation layer 626. The copper ions in the molten salt bath react with the cobalt plate of the first active metal plate 622 to form metallic copper powder, i.e., impurity a. The residence time t3 of the molten salt bath in the first displacement impurity removal chamber is controlled to be 6 h, thereby controlling the impurity removal rate. The copper powder settles at the bottom of the precipitation cone to the first precipitation outlet 624 and is collected by the first precipitation collection tank 625. The remaining molten salt bath, i.e. the first melt, is discharged from the third discharge port 623 to the non-lithium active metal element displacement extraction chamber 720.

[0437] The first impurity removal stage, the displacement impurity removal reaction process, is as follows: CuCl₂ + Co = CoCl₂ + Cu

[0438] <Extraction stage of non-lithium active metal elements>

[0439] After the first impurity removal stage, the first molten liquid enters the non-lithium active metal element replacement extraction chamber 720 (as shown in Figure 4) at a rate of 60 g / h through the fourth feed port 721. The temperature T4 of the non-lithium active metal element replacement extraction chamber 720 is controlled at 350℃ by the fourth heating and insulation layer 726. Nickel and cobalt ions in the first molten liquid undergo a replacement reaction with the second active metal plate 722 (Zn plate) for 3 hours, generating metallic nickel powder and cobalt powder, which settle at the bottom of the sedimentation cone to the second sedimentation outlet 724 and are finally collected by the second sedimentation collection tank 725. The remaining molten salt bath, i.e., the second molten liquid, is discharged to the second impurity removal device 550 through the fourth discharge port 723. The net nickel production capacity is 12 g / h, and the net cobalt production capacity is 4 g / h.

[0440] The substitution extraction reaction process of nickel and cobalt is as follows: CoCl2 + 2Zn = ZnCl2 + Co NiCl2 + 2Zn = ZnCl2 + Ni

[0441] <Second stage of impurity removal>

[0442] The second melt, after non-lithium active metal element extraction, enters the second displacement and impurity removal chamber 820 through the fifth feed port 821 as shown in Figure 4 at a rate of 60 g / h. The temperature T5 of the second displacement and impurity removal chamber is controlled at 350℃ by the fifth heating and insulation layer 826. Zinc ions, i.e. impurity b, and manganese ions in the second melt undergo a displacement reaction with the aluminum plate of the third active metal plate 822. The reaction time t5 is 6 h, generating metallic zinc powder and manganese powder, which settle at the bottom of the precipitation cone to the third precipitation outlet 824 and are finally collected by the third precipitation collection tank 825. The remaining molten salt bath, i.e. the third melt, is discharged to the second metal element extraction device 560 through the fifth discharge port 823.

[0443] The displacement purification reaction process in the second purification stage is as follows: 3ZnCl2 + 2Al = 2AlCl3 + 3Zn 3MnCl2 + 2Al = 2AlCl3 + 3Mn

[0444] <Second Metal Element Extraction Stage>

[0445] The third molten liquid discharged from the fifth outlet 823 enters the second metal element extraction device 560 as shown in Figure 4. The flow diversion valve 938 controls all the third molten liquid to flow into the extraction extractor 930. The third molten liquid used for lithium extraction is cooled and crushed into powder through the sixth inlet 931 with cooling and crushing facilities at a flow rate of 60 g / h, and then enters the extraction extractor 930. Ethanol is used as the extractant in the extraction extractor 930, and the extraction temperature is controlled at 35℃ through the sixth heating and insulation layer 935. This dissolves the LiCl in the powder. The insoluble powder (mainly including NaAlO2, AlCl3, and NaAlCl4) is discharged from the powder outlet 934, dried at 60℃ by the dryer 936, and then flows into the third impurity removal chamber 570 via the diversion pipe 939. The solvent mixed in with the insoluble powder is evaporated in the dryer 936 and returned to the extraction extractor 930 through the solvent vapor pipe 937. The lithium-ion-containing powder... The extract is discharged from the sixth outlet 933 with ceramic fine filter and enters the lithium distillation extractor B940 through the seventh inlet 941. The temperature of T6 is controlled at 60°C through the seventh heating and insulation layer 945 to achieve solvent vaporization. The vapor is discharged from the seventh outlet 942 and enters the first dust collector 950 through the first steam inlet 951. It is filtered by the first dust collector filter 953 (mainly filtering out a small amount of solid LiCl carried by the extractant vapor). After filtration, the vapor is discharged from the first steam outlet 952 and returned to the extractor 930 through the steam reflux and replenishment inlet 932. In the lithium distillation extractor B940, the lithium salt obtained after solvent evaporation is discharged to the first product collection tank 944 through the first product outlet 943. In the first dust collector 950, the solid LiCl obtained after filtration by the first dust collector filter 953 is discharged to the first fine powder collection tank 955 through the first dust collection outlet 954. The LiCl product capacity obtained from the first product receiving tank 944 in this section is 2.8 g / h.

[0446] The powder, after being dried by the dryer 936, enters the third impurity removal chamber 570 at a rate of 60 g / h through the ninth feed port 571. The temperature of the third impurity removal chamber is controlled at 350℃ by the ninth heating and insulation layer 574. Under the action of the impurity removal system 572, by-products and impurities (including NaAlO2, etc.) are removed and collected, and the powder is discharged to the reflux pump group 580 through the ninth discharge port 573.

[0447] After purification, the third melt is returned to the melting chamber 520 via the reflux pump group 580 and then through the reflux pipeline 590 and the feed and return port 523, thus realizing the recycling of molten salt.

[0448] Based on the content of each metal element in the initial material, the recovery rates of nickel, cobalt, and lithium were 97.8%, 97.8%, and 98.8%, respectively.

[0449] Comparative Example 1-1

[0450] <Preprocessing Stage>

[0451] Twenty waste 18650 lithium cobalt oxide (LCO) batteries were soaked in brine to release their remaining charge. The batteries were then disassembled, and the positive electrode current collector and positive electrode material layer were separated. The positive electrode material layer was crushed and sieved to obtain the positive electrode material. The material contained 54.79 wt% Co, 6.45 wt% Li, 8.5% Cu impurities, and 0.05% Zn impurities. The waste LCO battery positive electrode material was fed into the pretreatment chamber 510 through the first feed inlet 511 shown in Figure 6. A magnetic separator and crusher mixer 512 was set to a mixing speed of 100 rpm, and the mixture was heated to 800°C and held for 3 hours to eliminate combustible impurities. It was then sieved through a 60-mesh screen 513 to obtain a solid mixture. After sieving through screen 513, the solid mixture was fed into the melting chamber 520 through the first discharge outlet 514 at a rate of 60 g / h, with 100 g of solid mixture being introduced at a time.

[0452] <Chlorination Reaction Stage>

[0453] In the melting chamber 520 shown in Figure 6, the temperature of the melting chamber 520 is maintained at 350°C by the second heating and insulation layer 525. 500g of LiAlCl4 is added through the feeding and return port 523 to carry out the chlorination reaction. The stirring speed of the stirrer 522 is 150rpm, and the mixture forms a molten salt bath, which flows out through the second discharge port 524 at a rate of 60g / h into the first electrolytic purification chamber 610.

[0454] <First stage of impurity removal>

[0455] In the first electrolytic depurification chamber 610 shown in Figure 6, the molten salt bath enters through the feed port 611 at a rate of 60 g / h. The temperature of the first electrolytic depurification chamber 610 is controlled at 400℃ by the heating insulation layer 617. Under the action of the anode inert electrode plate 612 and the cathode inert electrode plate 613, the electrolysis voltage is set to a constant voltage of 1V. According to the process settings, impurity copper settles at the bottom of the precipitation cone to the precipitation outlet 615 and is collected by the precipitation collection tank 616. The remaining molten salt bath is discharged from the outlet 614 to the non-lithium active metal element extraction chamber. In the actual electrolysis process, no Cu was found to be generated after depurification in the first electrolytic depurification chamber 610.

[0456] <Extraction stage of non-lithium active metal elements>

[0457] The molten salt bath, after passing through the first impurity removal stage, enters the non-lithium active metal element electrolytic extraction chamber 710 as shown in Figure 6. The molten salt bath enters through the feed inlet 711 at a rate of 60 g / h. The temperature of the non-lithium active metal element electrolytic extraction chamber is controlled at 400℃ by the heating and insulation layer 717. The electrolysis voltage is set to a constant 2.5V under the action of the anode inert electrode plate 712 and the cathode inert electrode plate 713. During electrolysis, the total electrolysis current is 0.5A. The non-lithium metal settles at the bottom of the precipitation cone to the precipitation outlet 715 and is collected by the precipitation collection tank 716. In the actual experiment, no recovered product Co was found. After electrolysis, the molten salt bath is discharged through the outlet 714 to the second impurity removal stage.

[0458] <Second stage of impurity removal>

[0459] The molten salt bath, after extraction of non-lithium active metal elements, enters the second electrolytic impurity removal chamber 810 as shown in Figure 6. The molten salt bath enters at a rate of 60 g / h through the feed inlet 811. The tank temperature is controlled at 400℃ by the heating insulation layer 817. Under the action of the anode inert electrode plate 812 and the cathode inert electrode plate 813, the electrolysis voltage is set to a constant 3.5V. Impurities settle at the bottom of the sedimentation cone to the sedimentation outlet 815 and are collected by the sedimentation collection tank 816. The remaining molten salt bath is discharged through the outlet 814 to the second metal element extraction stage. During the actual electrolysis process, no Zn was observed to be generated in the second impurity removal chamber 810 after impurity removal.

[0460] <Second Metal Element Extraction Stage>

[0461] After the second impurity removal stage, the molten salt bath passes through the second metal element extraction device 560 as shown in Figure 5. The specific method is the same as in Example 1-1, and will not be repeated here.

[0462] In practice, because Co and other substances are not electrolyzed, the LiCl content of the product is ≤45%.

[0463] Because the recovery of Co and Li was poor, no further experiments were conducted.

[0464] As can be seen from Examples 1-1 and Comparative Examples 1-1, this application utilizes AlCl4-containing... - The molten salt reacts with the positive electrode material of spent batteries via a chlorination reaction. This process separates elements such as Li, Co, Ni, and Mn from oxygen in the spent batteries and combines them with chlorine to form chloride salts. This facilitates the extraction of non-lithium active metal elements from spent batteries through displacement reactions, resulting in high recovery capacity and rate of non-lithium active metal elements. It also ensures the purity and capacity of subsequent lithium or sodium extraction. Comparative Example 1-1 recovers non-lithium active metal elements through an electrolytic process using AlCl4.- During the electrolysis process, aluminum compounds or aluminum-manganese compounds are generated, which will affect the voltage of nickel-cobalt electrolysis. Therefore, it is not possible to extract non-lithium active metal elements, which also leads to low purity and low production capacity of the extracted lithium element. The content of LiCl in the recovered product is ≤45%.

[0465] Comparative Examples 1-2

[0466] <Preprocessing Stage>

[0467] Twenty used 18650 lithium cobalt oxide (LCO) batteries were soaked in brine to release their remaining charge. The batteries were then disassembled, and the positive electrode current collector and positive electrode material layer were separated. The positive electrode material layer was crushed and sieved to obtain the positive electrode material. The material contained 54.79 wt% Co, 6.45 wt% Li, 8.5% Cu impurities, and 0.05% Zn impurities. The used lithium cobalt oxide battery positive electrode material was fed into a pretreatment chamber 510 through the first inlet 511 (Figure 5). A magnetic separator / crusher / mixer 512 was set to a mixing speed of 100 rpm. The mixture was heated to 800°C and held for 3 hours to remove combustible impurities such as carbon powder. It was then sieved through a 60-mesh sieve 513 to obtain a solid mixture. After sieving through sieve 513, the solid mixture entered the melting chamber 520 through the first outlet 514 at a rate of 60 g / h. 100 g of the solid mixture was introduced at a time.

[0468] <Chlorination Reaction Stage>

[0469] In the melting chamber 520 shown in Figure 5, the temperature of the melting chamber 520 is maintained at 800℃ by the second heating and insulation layer 525 to ensure that NaCl melts. 500g of NaCl (mass ratio of solid mixture to molten salt 1:5) is added through the feeding and return port 523 to carry out the chlorination reaction. The stirring speed of the stirrer 522 is 150rpm to form a molten salt bath, which flows out through the second discharge port 524 at a rate of 60g / h into the first displacement and impurity removal chamber 620.

[0470] <First stage of impurity removal>

[0471] In the first displacement impurity removal chamber 620 shown in Figure 5, the molten salt bath enters through the third inlet 621 at a rate of 60 g / h. The temperature of the first displacement impurity removal chamber is controlled at 800℃ by the third heating and insulation layer 626. According to the process settings, the copper ions in the molten salt bath undergo a displacement reaction with the cobalt plate of the first active metal plate 622 to form metallic copper powder. The impurity removal rate is controlled by controlling the residence time of the molten salt bath in the first displacement impurity removal chamber. The copper powder settles at the bottom of the precipitation cone to the first precipitation outlet 624 and is collected by the first precipitation collection tank 625. The remaining molten salt bath is discharged through the third outlet 623 to the non-lithium active metal element displacement extraction chamber 720. In actual operation, no Cu was found to be generated after impurity removal in the first displacement impurity removal chamber 620.

[0472] <Extraction stage of non-lithium active metal elements>

[0473] The molten salt bath, after passing through the first impurity removal stage, enters the non-lithium active metal element replacement extraction chamber 720 (as shown in Figure 5) at a rate of 60 g / h through the fourth feed inlet 721. The temperature of the non-lithium active metal element replacement extraction chamber 720 is controlled at 800℃ by the fourth heating and insulation layer 726. According to the process settings, cobalt ions in the molten salt bath undergo a replacement reaction with the second active metal plate 722 (Zn plate), generating metallic cobalt powder which settles at the bottom of the precipitation cone to the second precipitation outlet 724. Finally, it is collected by the second precipitation collection tank 725, and the remaining molten salt bath is discharged through the fourth discharge outlet 723 to the second impurity removal device 550. In the actual process, no recovered product Co was found.

[0474] <Second stage of impurity removal>

[0475] The molten salt bath, after non-lithium active metal element extraction, enters the second displacement and impurity removal chamber 820 at a rate of 60 g / h through the fifth feed port 821 shown in Figure 5. The temperature of the second displacement and impurity removal chamber 820 is controlled at 800℃ by the fifth heating and insulation layer 826. According to the process settings, the zinc ions in the molten salt bath undergo a displacement reaction with the aluminum plate of the third active metal plate 822, generating metallic zinc powder which settles at the bottom of the precipitation cone to the third precipitation outlet 824 and is finally collected by the third precipitation collection tank 825. The remaining molten salt bath is discharged to the second metal element extraction device 560 through the fifth discharge port 823. In actual operation, no Zn was found to be generated after impurity removal in the second displacement and impurity removal chamber 820.

[0476] The subsequent experiments were discontinued because the impurities and Co element could not be extracted.

[0477] As can be seen from Examples 1-1 and Comparative Examples 1-2, the AlCl4-containing compounds used in this application -The molten salt in Comparative Examples 1-2 can chlorinate the metal elements in the battery cathode as a reducing agent, converting them into chloride salts. This chloride salt then facilitates a further displacement reaction, gradually replacing impurity metals and non-lithium active metals, thus improving the purity and recovery rate of non-lithium active metals and lithium or sodium elements. In contrast, Comparative Examples 1-2 used NaCl as the molten salt, which could not reduce the metals in the waste battery cathode material to chloride salts, preventing the subsequent displacement reaction and thus hindering the extraction of non-lithium active metals.

[0478] Example 2-1

[0479] <Preprocessing Stage>

[0480] Twenty used 18650 lithium cobalt oxide (LCO) batteries were soaked in salt water to release their remaining charge. The batteries were then disassembled, and the positive electrode current collector and positive electrode material layer were separated. The positive electrode material layer was then crushed and sieved to obtain the positive electrode material, which contained 54.79 wt% Co, 6.45 wt% Li, 8.5 wt% Cu impurities, and 0.05 wt% Zn impurities. Add 20g of carbon, and feed 180g of waste lithium cobalt oxide battery cathode material into the pretreatment chamber 510 through the first feed inlet 511 shown in Figure 13. Simultaneously, chlorine gas is introduced at a flow rate of 50L / h, for a total of 150L. A magnetic separator crusher / mixer 512 is set to a mixing speed of 100rpm for crushing. The material is then heated to 400℃ (T1) through the first heating and insulation layer 515 and held for 3 hours (t1) to eliminate combustible impurities such as carbon powder while simultaneously chlorinating. The mixture is then sieved through a 60-mesh sieve 513 to obtain a solid mixture. After sieving through sieve 513, the solid mixture enters the melting chamber 520 from the first discharge outlet 514 at a rate of 60g / h, with 100g of solid mixture introduced at a time. The formation reaction of the solid mixture is as follows: 2LiCoO2 + 3Cl2 + 2C = 2LiCl + 2CoCl2 + 2CO2

[0481] In the 180g waste lithium cobalt oxide battery cathode material, the molar amount of the first metal element Co (n1) is 1.67 mol, the molar amount of the second metal element Li (n2) is 1.67 mol, and since chlorine gas is in gaseous form, the molar amount of Cl in the introduced chlorine gas (n3) is greater than 5 mol (=1.67×2+1.67). The molar amount of the first reducing agent is 1.67 mol.

[0482] <Obtaining a molten salt bath system>

[0483] In the melting chamber 520 shown in Figure 13, the temperature T2 of the melting chamber 520 is maintained at 400℃ by the second heating and insulation layer 525. 250g of LiCl and 300g of KCl (the mass ratio of solid mixture to molten salt is 1:5.5) are added through the feeding and return port 523. The stirring speed of the stirrer 522 is 150rpm, and the mixture forms a molten salt bath. The molten salt bath flows out through the second discharge port 524 at a rate of 60g / h into the first electrolytic depurification chamber 610.

[0484] <First stage of impurity removal>

[0485] In the first electrolytic depurification chamber 610 shown in Figure 13, the molten salt bath enters through the third feed port 611 at a rate of 60 g / h. The temperature T3 of the first electrolytic depurification chamber 610 is controlled at 400℃ by the third heating and insulation layer 617. Under the action of the first anode inert electrode plate 612 (graphite in this embodiment) and the first cathode inert electrode plate 613 (graphite in this embodiment), the electrolysis voltage U1 is set to a constant voltage of 1V. The impurity copper ions in the molten salt bath are electrolyzed into metallic copper powder, i.e., impurity a. The impurity copper settles at the bottom of the precipitation cone to the first precipitation outlet 615 and is collected by the first precipitation collection tank 616. The remaining molten salt bath, i.e. the first melt, is discharged from the third discharge port 614 to the non-lithium active metal element electrolytic extraction chamber 710.

[0486] The electrolytic depurification reaction process in the first stage of impurity removal is as follows:

[0487] <Extraction stage of non-lithium active metal elements>

[0488] The first molten liquid, after passing through the first impurity removal stage, enters the non-lithium active metal element electrolytic extraction chamber 710 (as shown in Figure 13) at a rate of 60 g / h through the fourth feed inlet 711. The temperature T4 of the non-lithium active metal element electrolytic extraction chamber 710 is controlled at 400℃ by the fourth heating and insulation layer 717. Under the action of the second anode inert electrode plate 712 (graphite in this embodiment) and the second cathode inert electrode plate 713 (graphite in this embodiment), the electrolysis voltage U2 is set to a constant 2.5V, generating cobalt powder which settles at the bottom of the precipitation cone to the second precipitation outlet 715 and is finally collected by the second precipitation collection tank 716. The remaining molten salt bath, i.e., the second molten liquid, is discharged through the fourth outlet 714 to the second impurity removal device 550. During electrolysis, the total electrolysis current is 21A, and the cobalt production capacity is 29 g / h.

[0489] The electrolytic extraction reaction process of cobalt is as follows:

[0490] <Second stage of impurity removal>

[0491] The second melt, after extraction of non-lithium active metal elements, enters the second electrolytic depurification chamber 810 at a rate of 60 g / h through the fifth feed port 811 shown in Figure 13. The temperature T5 of the second electrolytic depurification chamber 810 is controlled at 400℃ by the fifth heating and insulation layer 817. Under the action of the third anode inert electrode plate 812 (graphite in this embodiment) and the third cathode inert electrode plate 813 (graphite in this embodiment), the electrolysis voltage U3 is set to a constant voltage of 3.5V. The zinc ions in the second melt are electrolyzed into metallic zinc powder, i.e., impurity b. The metallic zinc powder settles at the bottom of the precipitation cone to the third precipitation outlet 815 and is finally collected by the third precipitation collection tank 816. The remaining molten salt bath, i.e., the third melt, is discharged to the second metal element extraction device 560 through the fifth discharge port 814.

[0492] The electrolytic depurification reaction process in the second impurity removal stage is as follows:

[0493] <Second Metal Element Extraction Stage>

[0494] The third melt (mainly including LiCl and KCl) discharged from the second impurity removal stage enters the second metal element extraction device 560 shown in Figure 13 at a rate of 60 g / h. It is diverted by the diversion valve 938, thereby controlling the amount of the third melt flowing into the extraction extractor 930 and the diversion pipeline 939. The third melt, not used for lithium extraction, enters the third impurity removal chamber 570 at a flow rate of 3 g / h through the splitter pipe 939. The third melt used for lithium extraction is cooled and crushed into powder at a flow rate of 57 g / h through the tenth feed port 931 with cooling and crushing facilities (not shown in the figure), and then enters the extractor 930. Ethanol is used as the extractant in the extractor 930. The temperature of the extraction chamber 930A is controlled at 35°C by the tenth heating and insulation layer 935 to dissolve the lithium chloride in the powder. The insoluble powder (mainly including KCl) is discharged from the powder outlet 934, dried at 60°C by the dryer 936, and then discharged into the third impurity removal chamber 570. The solvent mixed in the insoluble powder is evaporated in the dryer 936 and returned to the extractor 930 through the solvent vapor pipe 937. The extract containing lithium ions is discharged from the tenth outlet 933 with ceramic fine filter (not shown in the figure) and enters the distillation lithium extractor B through the eleventh feed port 941. In section 940, the temperature T6 of the first distillation chamber 946 is controlled at 60℃ by the eleventh heating and insulation layer 945, achieving solvent vaporization. The vapor (ethanol) is discharged from the eleventh vapor outlet 942 and enters the first dust collector 950 through the first vapor inlet 951. It is filtered by the first dust filter 953 (mainly filtering the solid LiCl contained in the extractant vapor). After filtration, the vapor is discharged from the first vapor outlet 952 and returned to the extractor 930 through the vapor reflux and replenishment inlet 932. In the lithium distillation extractor B 940, the lithium salt obtained after solvent evaporation is discharged to the first product collection tank 944 through the first product outlet 943. In the first dust collector 950, the solid LiCl obtained after filtration by the first dust filter 953 is discharged to the first fine powder collection tank 955 through the first dust outlet 954. The LiCl product capacity obtained from the first product collection tank 944 in this section is 23g / h.

[0495] After being dried by the splitter and dryer 936, the powder is heated back to 400°C in the splitter pipeline 939 and then enters the third impurity removal chamber 570 at a rate of 60g / h through the thirteenth feed port 571. The temperature of the third impurity removal chamber 570 is controlled at 350°C by the thirteenth heating and insulation layer 574. Under the action of the impurity removal system 572, by-products and impurities are removed and collected, and then discharged to the reflux pump group 580 through the thirteenth discharge port 573.

[0496] After purification, the third melt is returned to the melting chamber 520 via the reflux pump group 580 and then through the reflux pipeline 590 and the feed and return port 523, thus realizing the recycling of molten salt.

[0497] The purity of the recovered cobalt was 99.8% and the purity of the recovered lithium chloride was 99.4% as determined by ICP testing. Based on the cobalt and lithium content in the initial battery cathode material, the recovery rates of cobalt and lithium chloride were 98.2% and 99.0%, respectively.

[0498] Example 2-2

[0499] <Preprocessing Stage>

[0500] Twenty discarded 18650 ternary (NCM523) batteries were soaked in salt water to release their remaining charge. The batteries were then disassembled, and the positive electrode current collector and positive electrode material layer were separated. The positive electrode material layer was then crushed and sieved to obtain the positive electrode material. The material contained 27.39 wt% Ni, 10.96 wt% Co, 14.83 wt% Mn, 6.45 wt% Li, 2.1% Cu, and 1.8% Al. 180g of waste NCM523 battery positive electrode material is fed into the pretreatment chamber 510 through the first feed port 511 shown in Figure 11. The temperature of the first heating and insulation layer 515 is set to 800℃ and held for 3 hours to eliminate combustible impurities. Then, 350g of ammonium chloride is fed into the pretreatment chamber 510 through the first feed port 511 at a rate of 350g / h. The temperature T1 of the first heating and insulation layer 515 is set to a constant 400℃ and held for 1h (t1) to further chlorinate the waste NCM523 battery positive electrode material. The magnetic separation crusher mixer 512 is set to a mixing speed of 100rpm for crushing, and then the mixture is screened through a 60-mesh screen 513 to obtain a solid mixture. After being screened through the screen 513, the solid mixture enters the melting chamber 520 through the first discharge port 514 at a rate of 60g / h, with 100g of solid mixture being introduced at a time.

[0501] The formation reaction of the solid mixture is as follows: 6LiNi 0.5 Co 0.2 Mn 0.3 O2+18NH4Cl=16NH3+6LiCl+3NiCl2+1.2CoCl2+1.8MnCl2+N2+12H2O

[0502] In the 180g of waste 18650 ternary lithium battery cathode material, the molar amounts of the first metal element Ni are 0.84 mol, Co is 0.33 mol, and Mn is 0.49 mol. Therefore, the molar amount of the first metal element n1 is 1.66 mol, and the molar amount of the second metal element Li is 1.67 mol. The added ammonium chloride has a molar amount of 6.54 mol. According to the above reaction formula, the molar amount of ammonium chloride as the first reducing agent is 1 / 9, and the molar amount as the chlorinating agent is 8 / 9. Therefore, the molar amount of Cl in the chlorinating agent is n3 is 5.81 mol, the molar amount of Cl in the first reducing agent is n4 is 0.73 mol, and the molar amount of the first reducing agent is also 0.73 mol.

[0503] <Obtaining a molten salt bath system>

[0504] In the melting chamber 520 shown in Figure 11, the temperature T2 of the melting chamber 520 is maintained at 400℃ by the second heating and insulation layer 525. 250g of LiCl and 300g of KCl (the mass ratio of solid mixture to molten salt is 1:5.5) are added through the feeding and return port 523. The stirring speed of the stirrer 522 is 150rpm, and the mixture forms a molten salt bath. The molten salt bath flows out through the second discharge port 524 at a rate of 60g / h into the first electrolytic depurification chamber 610.

[0505] <First stage of impurity removal>

[0506] In the first electrolytic depurification chamber 610 shown in Figure 11, the molten salt bath enters through the third feed port 611 at a rate of 60 g / h. The temperature T3 of the first electrolytic depurification chamber 610 is controlled at 400℃ by the third heating and insulation layer 617. Under the action of the first anode inert electrode plate 612 (graphite in this embodiment) and the first cathode inert electrode plate 613 (graphite in this embodiment), the electrolysis voltage U1 is set to a constant voltage of 1V. The impurity copper ions in the molten salt bath are electrolyzed into metallic copper powder, i.e., impurity a. The impurity copper settles at the bottom of the precipitation cone to the first precipitation outlet 615 and is collected by the first precipitation collection tank 616. The remaining molten salt bath, i.e. the first melt, is discharged from the third discharge port 614 to the non-lithium active metal element electrolytic extraction chamber 710.

[0507] The electrolytic depurification reaction process in the first stage of impurity removal is as follows:

[0508] <Extraction stage of non-lithium active metal elements>

[0509] The first molten liquid, after passing through the first impurity removal stage, enters the non-lithium active metal element electrolytic extraction chamber 710 (as shown in Figure 11) at a rate of 60 g / h through the fourth feed inlet 711. The temperature T4 of the non-lithium active metal element electrolytic extraction chamber 710 is controlled at 400℃ by the fourth heating and insulation layer 717. Under the action of the second anode inert electrode plate 712 (graphite in this embodiment) and the second cathode inert electrode plate 713 (graphite in this embodiment), the electrolysis voltage U2 is set to a constant 2V, generating cobalt and nickel powders. These powders settle at the bottom of the precipitation cone to the second precipitation outlet 715 and are finally collected by the second precipitation collection tank 716. The remaining molten salt bath, i.e., the second molten liquid, is discharged to the second impurity removal device 550 through the fourth discharge outlet 714. During electrolysis, the total electrolysis current is 21A, and the nickel production capacity is 16 g / h, and the cobalt production capacity is 6.5 g / h.

[0510] The electrolytic extraction reaction process for non-lithium active metal elements is as follows:

[0511] <Second stage of impurity removal>

[0512] The second melt, after extraction of non-lithium active metal elements, enters the second electrolytic depurification chamber 810 at a rate of 60 g / h through the fifth feed port 811 shown in Figure 11. The temperature T5 of the second electrolytic depurification chamber 810 is controlled at 400℃ by the fifth heating and insulation layer 817. Under the action of the third anode inert electrode plate 812 (graphite in this embodiment) and the third cathode inert electrode plate 813 (graphite in this embodiment), the electrolysis voltage U3 is set to a constant voltage of 3.2V. The aluminum ions in the second melt are electrolyzed into metallic aluminum powder, i.e., impurity b, and the manganese ions are electrolyzed into non-lithium active metallic manganese powder. The metallic aluminum powder and manganese powder settle at the bottom of the sedimentation cone 964 to the third sedimentation outlet 815 and are finally collected by the third sedimentation collection tank 816. The remaining molten salt bath, i.e., the third melt, is discharged to the second metal element extraction device 560 through the fifth discharge port 814.

[0513] The electrolytic depurification reaction process in the second impurity removal stage is as follows:

[0514] <Second Metal Element Extraction Stage>

[0515] The third melt (mainly including LiCl and KCl) discharged from the second impurity removal stage enters the second metal element extraction device 560 as shown in Figure 11 at a rate of 60 g / h. It is diverted by the diversion valve 938 to control the amount of the third melt flowing into the cooling crystallization device 960 and the diversion pipe 939. The third melt not used for lithium extraction enters the third impurity removal chamber 570 through the diversion pipe 939 at a flow rate of 3 g / h. The third melt used for lithium extraction enters the cooling crystallization device 960 at a rate of 57 g / h through the ninth inlet 961 with a ceramic fine filter (not shown in the figure). After lithium extraction, it is discharged into the third impurity removal chamber 570 through the ninth outlet 962 with a ceramic fine filter (not shown in the figure). In the cooling crystallization chamber 967, the crystallization temperature T6” is controlled at 350℃ by the ninth heating insulation layer 963. LiCl crystallizes out in the third melt and settles at the bottom of the settling cone 964, and is discharged from the settling outlet 965 into the settling collection tank 966. The LiCl production capacity is 22.8g / h.

[0516] The third melt, after lithium extraction, enters the third impurity removal chamber 570 at a rate of 60 g / h through the thirteenth feed port 571. The temperature of the third impurity removal chamber 570 is controlled at 350℃ by the thirteenth heating and insulation layer 574. Under the action of the impurity removal system 572, by-products and impurities are removed and collected, and then discharged to the reflux pump group 580 through the thirteenth discharge port 573.

[0517] After purification, the third melt is returned to the melting chamber 520 via the reflux pump group 580 and then through the reflux pipeline 590 and the feed and return port 523, thus realizing the recycling of molten salt.

[0518] Based on the content of each metal element in the initial material, the recovery rates of nickel, cobalt, manganese and lithium were 97.4%, 98.8%, 98.1% and 96.5%, respectively.

[0519] Example 2-3

[0520] Forty #5 spent nickel-metal hydride batteries were soaked in brine to release their remaining charge. The batteries were then disassembled, and the positive electrode current collector and positive electrode material layer were separated. The positive electrode material layer was crushed and sieved to obtain the positive electrode material. The material contained 45.6 wt% Ni, 3.2 wt% Co, 2.4 wt% Zn, 2.1% Cu, and 1.8% Al. 180 g of the spent nickel-metal hydride battery positive electrode material was fed into a pretreatment chamber 510 through the first feed inlet 511 (Figure 11). Subsequently, 240 g of ammonium chloride was added to the pretreatment chamber 510 through the first feed inlet 511 at a rate of 240 g / h. The temperature T1 of the first heating and insulation layer 515 was kept constant at 400℃ for 1 hour (t1) to chlorinate the spent nickel-metal hydride battery positive electrode material. A magnetic separator crusher / mixer 512 was used for crushing at 100 rpm, followed by sieving through a 60-mesh sieve 513 to obtain a solid mixture. After being screened by screen 513, the solid mixture enters the melting chamber 520 from the first discharge port 514 at a rate of 60g / h, with 100g of solid mixture being introduced.

[0521] The formation reaction of the solid mixture is as follows: Ni 0.9 Co 0.05 Zn 0.05 (OH)2+2NH4Cl=16NH3+0.9NiCl2+0.05CoCl2+0.05ZnCl2+2H2O

[0522] In 180g of waste nickel-hydrogen battery cathode material, the molar amount of the first metallic element Ni is 1.40mol and the molar amount of Co is 0.10mol, so the molar amount of the first metallic element n1 is 1.50mol. The molar amount of ammonium chloride added is 4.49mol, so the molar amount of Cl element in the chlorinating agent n3 is 4.49mol.

[0523] <Obtaining a molten salt bath system>

[0524] In the melting chamber 520 shown in Figure 11, the temperature T2 of the melting chamber 520 is maintained at 400℃ by the second heating and insulation layer 525. 1000g of LiCl-KCl (the mass ratio of solid mixture to molten salt is 1:10) with a mass ratio of 1:1.5 is added through the feeding and return port 523. The stirring speed of the stirrer 522 is 150rpm, and the mixture forms a molten salt bath. The molten salt bath flows out through the second discharge port 524 at a rate of 60g / h into the first electrolytic depurification chamber 610.

[0525] <First stage of impurity removal>

[0526] In the first electrolytic depurification chamber 610 shown in Figure 11, the molten salt bath enters through the third feed port 611 at a rate of 60 g / h. The temperature T3 of the first electrolytic depurification chamber 610 is controlled at 400℃ by the third heating and insulation layer 617. Under the action of the first anode inert electrode plate 612 (graphite in this embodiment) and the first cathode inert electrode plate 613 (graphite in this embodiment), the electrolysis voltage U1 is set to a constant voltage of 1V. The impurity copper ions in the molten salt bath are electrolyzed into metallic copper powder, i.e., impurity a. The impurity copper settles at the bottom of the precipitation cone to the first precipitation outlet 615 and is collected by the first precipitation collection tank 616. The remaining molten salt bath, i.e. the first melt, is discharged from the third discharge port 614 to the non-lithium active metal element electrolytic extraction chamber 710.

[0527] The electrolytic depurification reaction process in the first stage of impurity removal is as follows:

[0528] <Extraction stage of non-lithium active metal elements>

[0529] The first molten liquid, after passing through the first impurity removal stage, enters the non-lithium active metal element electrolytic extraction chamber 710 (as shown in Figure 11) at a rate of 60 g / h through the fourth feed port 711. The temperature T4 of the non-lithium active metal element electrolytic extraction chamber 710 is controlled at 400℃ by the fourth heating and insulation layer 717. Under the action of the second anode inert electrode plate 712 (graphite in this embodiment) and the second cathode inert electrode plate 713 (graphite in this embodiment), the electrolysis voltage U2 is set to a constant 2.5V, generating cobalt and nickel powders. These powders settle at the bottom of the precipitation cone to the second precipitation outlet 715 and are finally collected by the second precipitation collection tank 716. The remaining molten salt bath, i.e., the second molten liquid, is discharged to the second impurity removal device 550 through the fourth discharge port 714. During electrolysis, the total electrolysis current is 30A, and the prepared nickel production capacity is 27 g / h, and the cobalt production capacity is 1.8 g / h.

[0530] The electrolytic extraction reaction process for non-lithium active metal elements is as follows:

[0531] <Second stage of impurity removal>

[0532] The second melt, after extraction of non-lithium active metal elements, enters the second electrolytic depurification chamber 810 at a rate of 60 g / h through the fifth feed port 811 shown in Figure 11. The temperature T5 of the second electrolytic depurification chamber 810 is controlled at 400℃ by the fifth heating and insulation layer 817. Under the action of the third anode inert electrode plate 812 (graphite in this embodiment) and the third cathode inert electrode plate 813 (graphite in this embodiment), the electrolysis voltage U3 is set to a constant voltage of 3.5V. The aluminum ions in the second melt are electrolyzed into metallic aluminum powder, and the zinc ions are electrolyzed into zinc powder, i.e., impurity b. The metallic aluminum powder and zinc powder settle at the bottom of the sedimentation cone 964 to the third sedimentation outlet 815 and are finally collected by the third sedimentation collection tank 816. The remaining molten salt bath, i.e., the third melt, is discharged from the fifth discharge port 814 and directly enters the third impurity removal chamber 570 through the cooling crystallization device 960.

[0533] The electrolytic depurification reaction process in the second impurity removal stage is as follows:

[0534] After the second impurity removal stage, the third melt enters the third impurity removal chamber 570 through the thirteenth feed port 571 via the diversion pipe 939 at a rate of 60 g / h. The temperature of the third impurity removal chamber 570 is controlled at 350℃ by the thirteenth heating and insulation layer 574. Under the action of the impurity removal system 572, by-products and impurities are removed and collected, and then discharged to the reflux pump group 580 through the thirteenth discharge port 573.

[0535] After purification, the third melt is returned to the melting chamber 520 via the reflux pump group 580 and then through the reflux pipeline 590 and the feed and return port 523, thus realizing the recycling of molten salt.

[0536] Based on the content of each metal element in the initial material, the recovery rates of nickel and cobalt were 98.68% and 93.75%, respectively.

[0537] Examples 2-4

[0538] <Preprocessing Stage>

[0539] Twenty waste 18650 sodium batteries (positive electrode NaNiO2) were soaked in brine to release residual charge. The waste batteries were disassembled, and the positive current collector and positive electrode material layer of the obtained positive electrode were separated. The positive electrode material layer was crushed and sieved to obtain the positive electrode material. The content of Na was 18.7wt%, Ni was 47.14wt%, Cu was 2.1%, and Al was 1.8%. 180g of the waste 18650 sodium battery positive electrode material was put into the pretreatment chamber 510 through the first feed port 511 shown in Figure 11. The temperature of the first heating and insulation layer 515 was set to 800℃ and kept at that temperature for 3 hours to eliminate combustible impurities. Then, 260g of ammonium chloride was added into the pretreatment chamber 510 through the first feed port 511 at a rate of 260g / h. The temperature T1 of the first heating and insulation layer 515 was set to a constant 350℃ and kept at that temperature for 1h (t1) to further chlorinate the waste 18650 sodium battery positive electrode material. The magnetic separator crusher 512 is set to a mixing speed of 100 rpm for crushing, and then the mixture is screened through a 60-mesh screen 513 to obtain a solid mixture. After being screened by the screen 513, the solid mixture enters the melting chamber 520 from the first discharge port 514 at a rate of 60 g / h, with 100 g of solid mixture being introduced at a time.

[0540] The formation reaction of the solid mixture is as follows: 6NaNiO2 + 18NH4Cl = 16NH3 + 6NaCl + 6NiCl2 + N2 + 12H2O

[0541] In the 180g waste sodium battery cathode material, the molar amount of the first metal element Ni (n1) is 1.45 mol, and the molar amount of the second metal element Na (n2) is 1.46 mol. The molar amount of ammonium chloride added is 4.86 mol. According to the above reaction formula, the molar amount of ammonium chloride as the first reducing agent is 1 / 9, and the molar amount as the chlorinating agent is 8 / 9. Therefore, the molar amount of Cl in the chlorinating agent (n3) is 4.32 mol, the molar amount of Cl in the first reducing agent (n4) is 0.54 mol, and the molar amount of the first reducing agent is also 0.54 mol.

[0542] <Obtaining a molten salt bath system>

[0543] In the melting chamber 520 shown in Figure 11, the temperature T2 of the melting chamber 520 is maintained at 700℃ by the second heating and insulation layer 525. 500g of NaCl-KCl with a mass ratio of 1:1 (the mass ratio of solid mixture to molten salt is 1:5) is added through the feeding and return port 523. The stirring speed of the stirrer 522 is 150rpm, and the mixture forms a molten salt bath. The molten salt bath flows out through the second discharge port 524 at a rate of 60g / h into the first electrolytic depurification chamber 610.

[0544] <First stage of impurity removal>

[0545] In the first electrolytic depurification chamber 610 shown in Figure 11, the molten salt bath enters through the third feed port 611 at a rate of 60 g / h. The temperature T3 of the first electrolytic depurification chamber 610 is controlled at 700℃ by the third heating and insulation layer 617. Under the action of the first anode inert electrode plate 612 (graphite in this embodiment) and the first cathode inert electrode plate 613 (graphite in this embodiment), the electrolysis voltage U1 is set to a constant voltage of 0.8V. The impurity copper ions in the molten salt bath are electrolyzed into metallic copper powder, i.e., impurity a. The impurity copper settles at the bottom of the precipitation cone to the first precipitation outlet 615 and is collected by the first precipitation collection tank 616. The remaining molten salt bath, i.e. the first melt, is discharged from the third discharge port 614 to the non-lithium active metal element electrolytic extraction chamber 710.

[0546] The electrolytic depurification reaction process in the first stage of impurity removal is as follows:

[0547] <Extraction stage of non-lithium active metal elements>

[0548] The first molten liquid, after passing through the first impurity removal stage, enters the non-lithium active metal element electrolytic extraction chamber 710 (as shown in Figure 11) at a rate of 60 g / h through the fourth feed inlet 711. The temperature T4 of the non-lithium active metal element electrolytic extraction chamber 710 is controlled at 700℃ by the fourth heating and insulation layer 717. Under the action of the second anode inert electrode plate 712 (graphite in this embodiment) and the second cathode inert electrode plate 713 (graphite in this embodiment), the electrolysis voltage U2 is set to a constant 2.5V, generating metallic nickel powder. This powder settles at the bottom of the precipitation cone to the second precipitation outlet 715 and is finally collected by the second precipitation collection tank 716. The remaining molten salt bath, i.e., the second molten liquid, is discharged through the fourth outlet 714 to the second impurity removal device 550. During electrolysis, the total electrolysis current is 26.5A, and the nickel production capacity is 28 g / h.

[0549] The electrolytic extraction reaction process for non-lithium active metal elements is as follows:

[0550] <Second stage of impurity removal>

[0551] The second melt, after non-lithium active metal element extraction, enters the second electrolytic depurification chamber 810 at a rate of 60 g / h through the fifth feed port 811 shown in Figure 11. The temperature T5 of the second electrolytic depurification chamber 810 is controlled at 700℃ by the fifth heating and insulation layer 817. Under the action of the third anode inert electrode plate 812 (graphite in this embodiment) and the third cathode inert electrode plate 813 (graphite in this embodiment), the electrolysis voltage U3 is set to a constant voltage of 3.5V. The aluminum ions in the second melt are electrolyzed into metallic aluminum powder, i.e., impurity b. The metallic aluminum powder settles at the bottom of the sedimentation cone 964 to the third sedimentation outlet 815 and is finally collected by the third sedimentation collection tank 816. The remaining molten salt bath, i.e. the third melt, is discharged to the second metal element extraction device 560 through the fifth discharge port 814.

[0552] The electrolytic depurification reaction process in the second impurity removal stage is as follows:

[0553] <Second Metal Element Extraction Stage>

[0554] The third molten liquid (mainly NaCl and KCl) discharged from the second impurity removal stage enters the second metal element extraction device 560 as shown in Figure 11 at a rate of 60 g / h. It is diverted by the diversion valve 938 to control the amount of the third molten liquid flowing into the cooling crystallization device 960 and the diversion pipe 939. The third molten liquid not used for sodium extraction enters the third impurity removal chamber 570 through the diversion pipe 939 at a flow rate of 3 g / h. The third molten liquid used for sodium extraction enters the cooling crystallization device 960 at a rate of 57 g / h through the ninth inlet 961 with a ceramic fine filter (not shown in the figure). After sodium extraction, it is discharged into the third impurity removal chamber 570 through the ninth outlet 962 with a ceramic fine filter (not shown in the figure). In the cooling crystallization chamber 967, the crystallization temperature T6” is controlled at 450℃ by the ninth heating insulation layer 963. NaCl crystallizes out of the third melt and settles at the bottom of the settling cone 964, and is discharged from the settling outlet 965 into the settling collection tank 966. The production capacity of NaCl is 30g / h.

[0555] The third melt, after sodium extraction, enters the third impurity removal chamber 570 at a rate of 60 g / h through the thirteenth feed port 571. The temperature of the third impurity removal chamber 570 is controlled at 350℃ by the thirteenth heating and insulation layer 574. Under the action of the impurity removal system 572, by-products and impurities are removed and collected, and then discharged to the reflux pump group 580 through the thirteenth discharge port 573. [055...

Claims

1. A method for recycling used batteries, wherein, Includes the following steps: Pretreatment: The waste battery cathode material is pretreated to obtain a solid mixture; the solid mixture includes a first metal element, which is a non-lithium active metal element selected from at least one of nickel, cobalt, and manganese; Obtaining a molten salt bath: A solid mixture is mixed with molten salt to obtain a molten salt bath; First impurity removal stage: Remove impurity a; the metallic activity of impurity a is lower than that of either nickel or cobalt. Non-lithium active metal element extraction stage: extraction of nickel and / or cobalt; Second impurity removal stage: Remove impurity b; or, remove impurity b and extract metallic manganese; the metallic activity of impurity b is higher than that of either nickel or cobalt. In the pretreatment stage or the molten salt bath stage, chlorination or sulfidation reactions are carried out.

2. The method for recycling used batteries according to claim 1, wherein, Includes the following steps: S100, Pretreatment: Pretreatment of waste battery cathode material to obtain solid mixture; The solid mixture contains a first metal element and a second metal element, wherein the second metal element is selected from either lithium or sodium, and the first metal element is a non-lithium active metal element, wherein the non-lithium active metal element is selected from at least one of nickel, cobalt, and manganese. S200, Chlorination reaction: The solid mixture is mixed with molten salt to carry out a chlorination reaction, resulting in a molten salt bath. The molten salt contains AlCl4. - Compounds; S300, First impurity removal stage: The molten salt bath is subjected to a first displacement reaction with the first active metal plate. After precipitation, impurity a and the first melt are obtained, wherein the metal activity of impurity a is lower than that of either nickel or cobalt. S400, Non-lithium active metal element extraction stage: The first melt is subjected to a second displacement reaction with the second active metal plate. After precipitation, metallic nickel and / or metallic cobalt are extracted, and the second melt is obtained. S500, Second impurity removal stage: The second melt is subjected to a third displacement reaction with the third active metal plate. After precipitation, impurity b and the third melt are obtained, or impurity b, the third melt and metallic manganese are obtained. Among them, the metal activity of impurity b is higher than that of either nickel or cobalt. S600, Second metal element extraction stage: Extracting the second metal element from the third melt.

3. The waste battery recycling method according to claim 2, wherein, The molten salt is selected from at least one of NaAlCl4, LiAlCl4, and KAlCl4; Preferably, the mass ratio of the solid mixture to the molten salt is 1:3 to 1:20; more preferably, the mass ratio of the solid mixture to the molten salt is 1:5 to 1:

10. Preferably, the chlorination reaction comprises: NMO2 + QAlCl4 = QAlO2 + NCl + MCl2 + 1 / 2Cl2; wherein N is selected from at least one of Li and Na; M is selected from at least one of Co, Mn and Ni; and Q is selected from at least one of Li, K and Na. Preferably, the reaction temperature T2 of the chlorination reaction is 200℃~800℃; more preferably, the reaction temperature T2 of the chlorination reaction is 350℃~550℃.

4. The method for recycling waste batteries according to claim 2, wherein, In step S300, during the first impurity removal stage, the material of the first active metal plate is selected from any one of cobalt and nickel or their alloys; the reaction temperature T3 of the first displacement reaction is 300℃~400℃, and the reaction time t3 is 1h~10h. Preferably, in the non-lithium active metal element extraction stage of step S400, the material of the second active metal plate is selected from any one of zinc and manganese or their alloys; the reaction temperature T4 of the second displacement reaction is 300℃~400℃, and the reaction time t4 is 1h~5h. Preferably, in step S500, the material of the third active metal plate is selected from aluminum or its alloy; the reaction temperature T5 of the third displacement reaction is 300℃~400℃, and the reaction time t5 is 2h~10h. Preferably, impurity a includes Cu; impurity b includes Zn.

5. The waste battery recycling method according to claim 2, wherein it satisfies one of the following conditions: Condition a: The second metal element is selected from lithium, and the molten salt is LiAlCl4; or, the molten salt includes LiAlCl4, and at least one of NaAlCl4 and KAlCl4; the S600 extraction stage of the second metal element includes: The third melt is split, with one portion used for lithium extraction and the other portion returned to the molten salt after impurity removal; wherein, the lithium extraction includes: directly performing a fractional distillation treatment A on the split portion of the third melt to extract Li; or, first performing an extraction treatment on the split portion of the third melt, and then performing a fractional distillation treatment B to extract Li. Condition b: The second metal element is selected from lithium, and the molten salt is at least one of NaAlCl4 and KAlCl4; the S600 extraction stage of the second metal element includes: extracting lithium from all of the third melt; wherein, the lithium extraction includes: first extracting the third melt, and then distilling the obtained extract to extract Li element. Condition c: The second metal element is selected from sodium, and the molten salt is selected from NaAlCl4. The S600 extraction stage of the second metal element includes: splitting the third molten liquid, extracting sodium from one part, and returning the other part to the molten salt after removing impurities; wherein, the sodium extraction includes: directly distilling a portion of the split third molten liquid to extract Na.

6. The method for recycling waste batteries according to claim 5, wherein, The distillation process A includes: heating the third melt at a temperature T6, where T6 is 480°C to 550°C, to evaporate the flux AlCl3 in the third melt and obtain a solid second metal chloride. Preferably, the extraction process includes: cooling the third melt and crushing it into powder, dissolving the LiCl in the powder using an extractant to obtain the extract, wherein the extractant includes at least one of acetone, cyclohexanone, methanol, ethanol, isopropanol, and diethyl ether; the distillation process B includes: heating the extract at a temperature T6', where T6' is 60°C to 200°C, to evaporate the extractant in the extract to obtain LiCl.

7. The method for recycling waste batteries according to claim 1, wherein, Includes the following steps: S100, Pretreatment: Pretreatment of waste battery positive electrode material to obtain a solid mixture, wherein the pretreatment includes pretreatment chlorination or pretreatment sulfidation; The solid mixture includes a first metal element, which is a non-lithium active metal element selected from at least one of nickel, cobalt, and manganese. The pretreatment chlorination includes: mixing the positive electrode material with at least a chlorinating agent to carry out a chlorination reaction to obtain the solid mixture, wherein the solid mixture includes a chloride of a first metal element; The pretreatment sulfidation includes: mixing the cathode material with at least a sulfur source to carry out a sulfation reaction to obtain the solid mixture, wherein the solid mixture includes the sulfate of a first metal element; S200, Obtaining a molten salt bath system: The solid mixture is mixed with molten salt, and after melting, a molten salt bath is formed; S300, First impurity removal stage: Remove impurity a; the metal activity of impurity a is lower than that of either nickel or cobalt. S400, Non-lithium Active Metal Element Extraction Stage: Extraction of Nickel and / or Cobalt; S500, Second impurity removal stage: Remove impurity b; or, remove impurity b and extract metallic manganese; The metal activity of impurity b is higher than that of either nickel or cobalt.

8. The method for recycling waste batteries according to claim 7, wherein, The chlorinating agent used in the pretreatment chlorination is selected from at least one of Cl2, NH4Cl, and HCl; Preferably, the solid mixture is obtained by mixing the positive electrode material with a chlorinating agent and performing a chlorination reaction, comprising: mixing the positive electrode material with a chlorinating agent and performing a chlorination reaction to obtain the solid mixture; more preferably, the molar amount of the first metal element in the positive electrode material is n1, the molar amount of the second metal element is n2, and the molar amount of Cl element in the chlorinating agent is n3, satisfying n3≥2n1+n2, wherein n1>0, n2≥0; Preferably, the solid mixture is obtained by mixing the positive electrode material with a chlorinating agent and performing a chlorination reaction, comprising: mixing the positive electrode material with a chlorinating agent and a first reducing agent and performing a chlorination reaction to obtain the solid mixture; wherein the first reducing agent is selected from at least one of coke, coal powder, NH4Cl, HCl, and CO; more preferably, the molar amount of the first metal element in the positive electrode material is n1, the molar amount of the second metal element is n2, the molar amount of Cl element in the chlorinating agent is n3, and the molar amount of Cl element in the first reducing agent is n4, satisfying n3+n4≥2n1+n2, wherein n1>0, n2≥0, and n4≥0; Preferably, the solid mixture is obtained by mixing the positive electrode material with at least one chlorinating agent and performing a chlorination reaction, comprising: mixing the positive electrode material with a chlorinating agent, a first reducing agent, and a first oxidizing agent and performing a chlorination reaction to obtain the solid mixture; wherein, the first reducing agent is selected from at least one of coke, coal powder, NH4Cl, HCl, and CO; the first oxidizing agent is selected from at least one of O2, O3, and MnO2; more preferably, the molar amount of the first metal element in the positive electrode material is n1, the molar amount of the second metal element is n2, the molar amount of Cl element in the chlorinating agent is n3, and the molar amount of Cl element in the first reducing agent is n4, satisfying n3+n4≥2n1+n2, wherein n1>0, n2≥0, and n4≥0; Preferably, the conditions for the chlorination reaction include: a temperature T1 of 300℃ to 900℃ and a time t1 of 0.1h to 10h.

9. The method for recycling used batteries according to claim 7, wherein, The sulfur source in the pretreatment sulfidation is selected from at least one of (NH4)2SO4, SO2, and H2SO4; Preferably, the solid mixture is obtained by mixing the cathode material with a sulfur source at least and performing a sulfation reaction, comprising: mixing the cathode material with a sulfur source and performing a sulfation reaction to obtain the solid mixture; more preferably, the molar amount of the first metal element in the cathode material is n1, the molar amount of the second metal element is n2, and the molar amount of S element in the sulfur source is n5, satisfying n5≥n1+0.5n2, wherein n1>0, n2≥0; Preferably, the solid mixture is obtained by mixing the positive electrode material with at least a sulfur source and performing a sulfation reaction, comprising: mixing the positive electrode material with a sulfur source and a second reducing agent and performing a sulfation reaction to obtain the solid mixture; wherein the second reducing agent is selected from at least one of coke, pulverized coal, SO2, (NH4)2SO4, and CO; more preferably, the molar amount of the first metal element in the positive electrode material is n1, the molar amount of the sulfur element in the sulfur source is n5, and the molar amount of the sulfur element in the second reducing agent is n6, satisfying n5+n6≥n1+0.5n2, wherein n1>0, n2≥0, and n6≥0; Preferably, the solid mixture is obtained by mixing the positive electrode material with at least a sulfur source and performing a sulfation reaction, comprising: mixing the positive electrode material with a sulfur source, a second reducing agent, and a second oxidizing agent and performing a sulfation reaction to obtain the solid mixture; wherein, the second reducing agent is selected from at least one of coke, pulverized coal, SO2, (NH4)2SO4, and CO; the second oxidizing agent is selected from at least one of O2, O3, and MnO2; more preferably, the molar amount of the first metal element in the positive electrode material is n1, the molar amount of the second metal element is n2, the molar amount of S element in the sulfur source is n5, and the molar amount of S element in the second reducing agent is n6, satisfying n5+n6≥n1+0.5n2, wherein n1>0, n2≥0, and n6≥0; Preferably, the conditions for the sulfation reaction include: a temperature T1' of 300℃ to 900℃ and a time t1' of 0.1h to 10h.

10. The method for recycling waste batteries according to claim 7, wherein, In step S200, the melting temperature T2 is 200℃~800℃; Preferably, the melting temperature T2 is 350℃~700℃; Preferably, the mass ratio of the solid mixture to the molten salt is 1:3 to 1:

20.

11. The method for recycling waste batteries according to claim 7, wherein, In step S300, the first impurity removal stage includes: performing a first electrolysis on the molten salt bath, and after precipitation, obtaining impurity a and a first melt; in step S400, the non-lithium active metal element extraction stage includes: performing a second electrolysis on the first solution, and after precipitation, extracting nickel and / or cobalt, and obtaining a second melt; in step S500, the second impurity removal stage includes: performing a third electrolysis on the second melt, and after precipitation, obtaining impurity b and a third melt; or, obtaining impurity b, the third melt, and metallic manganese; Preferably, in step S300, the conditions for the first electrolysis include: the electrolysis voltage U1 is in the range of 0.5V ≤ U1 ≤ 1V, and the electrolysis temperature T3 is in the range of 350℃ ≤ T3 ≤ 700℃; in step S400, the conditions for the second electrolysis include: the electrolysis voltage U2 is in the range of 1V < U2 ≤ 2.5V, and the electrolysis temperature T4 is in the range of 350℃ ≤ T4 ≤ 700℃; in step S500, the conditions for the third electrolysis include: the electrolysis voltage U3 is in the range of 2.5V < U3 ≤ 3.5V, and the electrolysis temperature T5 is in the range of 350℃ ≤ T5 ≤ 700℃. Preferably, the cathode and anode in the first, second, and third electrolysis are independently selected from any one of the inert electrodes; the inert electrode includes one of the following: nickel plate, copper plate, stainless steel plate, graphite plate, platinum plate, and silver plate. Preferably, the molten salt is selected from at least one of LiCl, NaCl, KCl, AlCl3, ZnCl2, NaBr, KBr, Na2CO3, K2CO3, Na2SO4, and KNO3; Preferably, impurity a includes Cu; impurity b includes at least one of Zn and Al.

12. The method for recycling waste batteries according to claim 7, wherein, In step S300, the first impurity removal stage includes: subjecting the molten salt bath to a first displacement reaction with a first active metal plate, and after precipitation, obtaining impurity a and a first melt; In step S400, the non-lithium active metal element extraction stage includes: subjecting the first melt to a second displacement reaction with a second active metal plate, and after precipitation, extracting nickel and / or cobalt, and obtaining a second melt; In step S500, the second impurity removal stage includes: subjecting the second melt to a third displacement reaction with a third active metal plate, and after precipitation, obtaining impurity b and a third melt; or, obtaining impurity b, the third melt, and metallic manganese; Preferably, in step S300, the material of the first active metal plate is selected from any one of cobalt and nickel or their alloys; the reaction temperature T3' of the first displacement reaction is 300℃~400℃, and the reaction time t3' is 1h~10h; in step S400, the material of the second active metal plate is selected from any one of zinc and manganese or their alloys; the reaction temperature T4' of the second displacement reaction is 300℃~400℃, and the reaction time t4' is 1h~5h; in step S500, the material of the third active metal plate is selected from aluminum or its alloy; the reaction temperature T5' of the third displacement reaction is 300℃~400℃, and the reaction time t5' is 2h~10h. Preferably, the molten salt is selected from at least one of LiCl, NaCl, KCl, AlCl3, ZnCl2, NaBr, KBr, Na2CO3, K2CO3, Na2SO4, KNO3, NaAlCl4, LiAlCl4, and KAlCl4; Preferably, impurity a includes Cu; impurity b includes at least one of Zn and Al.

13. The method for recycling waste batteries according to claim 11 or 12, wherein, The solid mixture further includes a second metallic element, which is selected from either lithium or sodium; the waste battery recycling method further includes the following step: S600, extraction of the second metallic element stage: extracting the second metallic element from the third melt; Preferably, the extraction of the second metal element from the third melt includes any of the following methods: Method 1: directly distilling the third melt to extract the second metal element; Method 2: first extracting the third melt, and then distilling the resulting extract to extract the second metal element; Method 3: cooling and crystallizing the third melt to extract the second metal element.

14. The waste battery recycling method according to claim 13, wherein it satisfies one of the following conditions: Condition a: The second metal element is selected from lithium, and the molten salt is selected from molten salts that do not contain lithium. Step S600, the extraction stage of the second metal element, includes: The third melt is subjected to lithium extraction; wherein the lithium extraction includes: first extracting the third melt, and then distilling the resulting extract to extract Li. Condition b: The second metal element is selected from lithium, the molten salt includes LiCl and / or LiAlCl4, and optionally a molten salt that does not contain lithium. Step S600, the extraction stage of the second metal element, includes: splitting the third melt, extracting lithium from one part, and returning the other part to the molten salt after removing impurities; wherein, the lithium extraction includes: first extracting the split part of the third melt, and then performing distillation B to extract Li. Condition c: The second metal element is selected from lithium, and the molten salt is LiAlCl4, or the molten salt is LiCl and LiAlCl4. The extraction stage of the second metal element in step S600 includes: splitting the third melt, extracting lithium from one part, and returning the other part to the molten salt after removing impurities; wherein, the lithium extraction includes: directly distilling the split part of the third melt A to extract Li element; Condition d: The second metal element is selected from lithium, and the molten salt is KCl, or the molten salt is LiCl and KCl. Step S600, the stage of extracting the second metal element, includes: extracting lithium from all of the third melt; or, splitting the third melt, extracting lithium from one part, and returning the other part to the molten salt after removing impurities; wherein, the lithium extraction includes: cooling and crystallizing the third melt to extract Li element; Condition e: The second metal element is selected from sodium, and the molten salt is NaAlCl4, or the molten salt is NaCl and NaAlCl4. Step S600, the extraction stage of the second metal element, includes: splitting the third molten liquid, extracting sodium from one part, and returning the other part to the molten salt after removing impurities; wherein, the extraction of sodium includes: directly distilling the split part of the third molten liquid A to extract the Na element; Condition f: The second metal element is selected from sodium, and the molten salt is KCl, or the molten salt is NaCl and KCl. Step S600, the extraction stage of the second metal element, includes: extracting sodium from all of the third melt; or, splitting the third melt, extracting sodium from one part, and returning the other part to the molten salt after removing impurities; wherein, the extraction of sodium includes: cooling and crystallizing the third melt to extract Na element.

15. The method for recycling waste batteries according to claim 13, wherein, The extraction process includes: cooling the third melt and crushing it into powder, dissolving the LiCl in the powder using an extractant to obtain the extract, wherein the extractant is selected from at least one of acetone, cyclohexanone, methanol, ethanol, isopropanol, and diethyl ether; the distillation process B includes: heating the extract at a temperature T6, where T6 is 60℃~200℃, to evaporate the extractant in the extract to obtain LiCl; Preferably, the distillation process A includes: heating the third melt at a temperature T6', where T6' is 480°C to 550°C, to evaporate the co-solvent AlCl3 in the third melt and obtain a solid second metal chloride; Preferably, the cooling crystallization includes: cooling the third melt to T6”, causing the second metal chloride in the third melt to precipitate, and obtaining a solid second metal chloride; wherein the second metal element is lithium, and T6” is 345℃~360℃; or the second metal element is sodium, and T6” is 420℃~500℃.

16. A waste battery recycling device, used in any one of the waste battery recycling methods according to claims 1 to 15.

17. The waste battery recycling device according to claim 16, used in the waste battery recycling method according to any one of claims 1 to 6; the waste battery recycling device includes a pretreatment device, a melting device, a first impurity removal device, a non-lithium active metal element extraction device, a second impurity removal device, and a second metal element extraction device; the pretreatment device includes a first inlet and a first outlet, the melting device includes a second inlet and a second outlet, the first impurity removal device includes a third inlet and a third outlet, the non-lithium active metal element extraction device includes a fourth inlet and a fourth outlet, and the second impurity removal device includes a fifth inlet and a fifth outlet; the first outlet is connected to the second inlet; the second outlet is connected to the third inlet; the third outlet is connected to the fourth inlet; the fourth outlet is connected to the fifth inlet; and the fifth outlet is connected to the second metal element extraction device; wherein... The melting device is used to carry out the chlorination reaction.

18. The waste battery recycling device according to claim 17, wherein, The pretreatment device also includes a pretreatment chamber, a magnetic separation crusher and mixer, a first heating and insulation layer, and a screen. The melting device also includes a melting chamber, a stirrer, a feeding and return port, and a second heating and insulation layer; The first impurity removal device also includes a first displacement impurity removal chamber, a first active metal plate, a first precipitation outlet, a first precipitation receiving tank, and a third heating and insulation layer; The non-lithium active metal element extraction device also includes a non-lithium active metal element replacement extraction chamber, a second active metal plate, a second precipitation outlet, a second precipitation receiving tank, and a fourth heating and insulation layer. The second impurity removal device also includes a second displacement impurity removal chamber, a third active metal plate, a third sedimentation outlet, a third sedimentation receiving tank, and a fifth heating and insulation layer.

19. The waste battery recycling device according to claim 17, wherein, The second metal element extraction device includes an extraction extractor, a distillation extractor B, and a first dust collector connected in sequence in a direction away from the second impurity removal device; The extraction device includes a sixth feed inlet, a sixth discharge outlet, a powder discharge outlet, a sixth heating and insulation layer, a dryer, a solvent vapor pipeline, a vapor reflux and replenishment inlet, and an extraction chamber; The distillation extractor B includes a seventh inlet, a seventh outlet, a first product outlet, a first product collection tank, a seventh heating and insulation layer, and a first distillation chamber; The first dust collector includes a first steam inlet, a first steam outlet, a first dust collection outlet, a first dust collection filter, a first fine powder collection tank, and a first dust collection chamber.

20. The waste battery recycling device according to claim 17, wherein, The second metal element extraction device includes a distillation extractor A and a second dust collector connected in sequence along a direction away from the second impurity removal device; The distillation extractor A includes an eighth inlet, an eighth outlet, a second product outlet, a second product collection tank, an eighth heating and insulation layer, and a second distillation chamber. The second dust collector includes a second steam inlet, a second steam outlet, a second dust filter, a second dust outlet, a second fine powder collection tank, and a second dust collection chamber.

21. The waste battery recycling device according to claim 19 or 20, wherein, The second metal element extraction device further includes a diversion pipeline and a diversion valve; one end of the diversion pipeline and the diversion valve are located between the fifth discharge port and the sixth inlet port; or, one end of the diversion pipeline and the diversion valve are located between the fifth discharge port and the eighth inlet port; Preferably, the height of the first discharge port is higher than the height of the second feed port; the height of the second discharge port is higher than the height of the third feed port; the height of the third discharge port is higher than the height of the fourth feed port; the height of the fourth discharge port is higher than the height of the fifth feed port; and the height of the fifth discharge port is higher than the height of the sixth feed port or higher than the height of the eighth feed port.

22. The waste battery recycling device according to claim 17, further comprising a purification device and a reflux device connected sequentially in a direction away from the second metal element extraction device, wherein the purification device is connected to the second metal element extraction device; the reflux device is connected to the purification device and the melting device, and is used to return molten salt to the melting device.

23. The waste battery recycling device according to claim 16, used in the waste battery recycling method according to any one of claims 1, 7 to 15; the waste battery recycling device comprises a pretreatment device, a melting device, a first impurity removal device, a non-lithium active metal element extraction device, and a second impurity removal device connected in sequence. Preferably, the pretreatment device includes a first inlet, a first outlet, a pretreatment chamber, a magnetic separation crusher and mixer, a first heating and insulation layer, and a screen; the melting device includes a second inlet, a second outlet, a melting chamber, a stirrer, a feeding and return inlet, and a second heating and insulation layer; the first impurity removal device includes a third inlet, a third outlet, a first electrolytic impurity removal chamber, a first anode inert electrode plate, a first cathode inert electrode plate, a first precipitation collection tank, a first precipitation outlet, and a third heating and insulation layer; the non-lithium active metal element extraction device includes a fourth inlet, a fourth outlet, and a non-lithium active metal element extraction device. The device comprises a metal element electrolytic extraction chamber, a second anode inert electrode plate, a second cathode inert electrode plate, a second precipitation collection tank, a second precipitation outlet, and a fourth heating and insulation layer; the second impurity removal device includes a fifth inlet, a fifth outlet, a second electrolytic impurity removal chamber, a third anode inert electrode plate, a third cathode inert electrode plate, a third precipitation collection tank, a third precipitation outlet, and a fifth heating and insulation layer; the first outlet is connected to the second inlet, the second outlet is connected to the third inlet, the third outlet is connected to the fourth inlet, and the fourth outlet is connected to the fifth inlet; Preferably, the pretreatment device includes a first feed inlet, a first discharge outlet, a pretreatment chamber, a magnetic separation crusher and mixer, a first heating and insulation layer, and a screen; the melting device includes a second feed inlet, a second discharge outlet, a melting chamber, a stirrer, a feeding and return inlet, and a second heating and insulation layer; the first impurity removal device includes a sixth feed inlet, a sixth discharge outlet, a first displacement impurity removal chamber, a first active metal plate, a fourth precipitation outlet, a fourth precipitation collection tank, and a sixth heating and insulation layer; the non-lithium active metal element extraction device includes a seventh feed inlet and a seventh discharge outlet. The first discharge port is connected to the second discharge port, the second discharge port is connected to the sixth discharge port, the sixth discharge port is connected to the seventh discharge port, and the seventh discharge port is connected to the eighth discharge port.

24. The waste battery recycling device according to claim 23, wherein, The device further includes a second metal element extraction device, which is connected to the second impurity removal device. Preferably, the second metal element extraction device includes a cooling crystallization device; the cooling crystallization device includes a ninth inlet, a ninth outlet, a cooling crystallization chamber, a sedimentation cone bottom, a sedimentation outlet, a sedimentation collection tank, and a ninth heating and insulation layer; Preferably, the second metal element extraction device includes an extraction extractor, a distillation extractor B, and a first dust collector connected sequentially in the direction away from the second impurity removal device; the extraction extractor includes a tenth feed inlet, a tenth discharge outlet, a powder discharge outlet, a tenth heating and insulation layer, a dryer, a solvent vapor pipeline, a vapor reflux and replenishment inlet, and an extraction chamber; the distillation extractor B includes an eleventh feed inlet, an eleventh discharge outlet, a first product outlet, a first product collection tank, an eleventh heating and insulation layer, and a first distillation chamber; the first dust collector includes a first vapor inlet, a first vapor outlet, a first dust collection outlet, a first dust collection filter, a first fine powder collection tank, and a first dust collection chamber; Preferably, the second metal element extraction device includes a distillation extractor A and a dust collector connected sequentially in a direction away from the second impurity removal device; the distillation extractor A includes a twelfth feed inlet, a twelfth discharge outlet, a second product outlet, a second product collection tank, a twelfth heating and insulation layer, and a second distillation chamber; the second dust collector includes a second steam inlet, a second steam outlet, a second dust filter, a second dust outlet, a second fine powder collection tank, and a first dust collection chamber.

25. The waste battery recycling device according to claim 24, wherein, The second metal element extraction device further includes a diversion pipeline and a diversion valve; one end of the diversion pipeline and the diversion valve are located between the fifth discharge port and the ninth inlet port; Preferably, the second metal element extraction device further includes a diversion pipeline and a diversion valve; one end of the diversion pipeline and the diversion valve are located between the fifth discharge port and the tenth inlet port; or, one end of the diversion pipeline and the diversion valve are located between the eighth discharge port and the tenth inlet port. Preferably, the second metal element extraction device further includes a diversion pipeline and a diversion valve; one end of the diversion pipeline and the diversion valve are located between the eighth discharge port and the twelfth inlet port; or, one end of the diversion pipeline and the diversion valve are located between the fifth discharge port and the twelfth inlet port.

26. The waste battery recycling device according to claim 24, further comprising the purification device and the reflux device connected sequentially in a direction away from the second metal element extraction device, wherein the purification device is connected to the second metal element extraction device; the reflux device is connected to the purification device and the melting device, and is used to reflux molten salt back into the melting device.

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