Method and special equipment for low-temperature acid-free closed-loop recovery of all-solid-state battery

Abstract

The invention relates to the field of solid-state battery recovery, and provides a method and special equipment for low-temperature acid-free closed-loop recovery of an all-solid-state battery. According to the method, special equipment is matched with the method, efficient metal separation is carried out on the mixed powder of the positive electrode and the negative electrode through reduction, wet grinding and magnetic separation, the obtained metal is high in purity and can be used for preparing a secondary battery, and byproducts generated in the period can be recycled as building material additives; and finally realizing high-valued and closed-loop recovery of lithium, transition metal, solid electrolyte and a current collector in the sulfide-oxide composite all-solid-state battery material under the conditions that the temperature is less than or equal to 300 DEG C and the pressure is normal.

Description

Technical Field

[0001] This invention relates to the field of solid-state battery recycling, and more particularly to a method and dedicated equipment for low-temperature, acid-free closed-loop recycling of all-solid-state batteries. Background Technology

[0002] As modern society's demand for high-energy-density all-solid-state batteries gradually increases, the number of companies engaged in the large-scale production of all-solid-state batteries is also gradually growing, leading to a larger scale of waste all-solid-state batteries. Retired sulfide all-solid-state batteries easily produce highly toxic gases such as hydrogen fluoride and hydrogen sulfide, and also contain various high-value-added energy metals such as lithium, nickel, cobalt, and manganese. Their resource recycling is a key issue for the healthy development of the battery industry. All-solid-state batteries contain a significant amount of sulfide solid electrolytes and metal positive and negative electrodes (retired ASSBs simultaneously contain high-value elements such as Li, Ni, Co, Mn, Cu, Al, S, and P, as well as toxic sulfide electrolytes such as...). Traditional lithium-ion battery recycling methods (wet / fire processes) produce toxic H2S gas and cannot effectively recycle positive and negative electrode materials.

[0003] Currently, there are few methods for the resource recovery of retired sulfide-based solid-state batteries. The main approach is to prioritize the recovery of the sulfide solid electrolyte and then break down the ternary materials at high temperatures to recover related metals. However, this recovery method usually has the following drawbacks: (1) Produced by high-temperature roasting or hydrolysis , Harmful gases; (2) Strong acid leaching leads to high wastewater treatment costs; (3) Solid electrolytes are difficult to separate from positive and negative electrode powders efficiently, resulting in low metal recovery rate (<85%). Therefore, there is an urgent need to develop a closed-loop recycling method for all-solid-state batteries that is low-temperature, acid-free, and free of secondary pollution. Summary of the Invention

[0004] To address the technical problems existing in the background art, this invention proposes a method for low-temperature, acid-free closed-loop recycling of all-solid-state batteries, comprising the following steps: A1. The positive and negative electrode mixed powders are reacted with a reducing agent to obtain alloy particles and lithium vapor, respectively. A2. Collect lithium vapor into solid metallic lithium; A3. After wet grinding of the alloy particles, magnetic separation was performed to obtain Cu and magnetic alloy respectively.

[0005] In step A1, the reducing agent is graphite powder; Preferably, the C / O molar ratio of the positive and negative electrode mixed powder to the graphite powder is 1.2:1; Preferably, the reduction reaction temperature is 700-900℃; Preferably, the reduction reaction time is 20-60 min.

[0006] Step A1 further includes A1-1, cooling and crushing the all-solid-state battery to obtain a mixture; Preferably, the cooling temperature of the all-solid-state battery is -40°C; Preferably, the particle size of the mixture is <10mm.

[0007] Step A1 further includes A1-2, sublimating the mixture under vacuum to obtain a sulfide electrolyte; Preferably, the temperature of the vacuum sublimation is 250-300℃; Preferably, the pressure of the vacuum sublimation is <100 Pa; Preferably, the vacuum sublimation time is 40-90 min; More preferably, the sulfide electrolyte is regenerated into a solid electrolyte sheet through ball milling, cold pressing, and annealing.

[0008] Step A1 further includes A1-3, performing magnetic separation on the vacuum sublimated mixture to obtain ferromagnetic current collector and copper-rich aluminum material respectively; Step A1 further includes A1-4, mechanically peeling off the copper-rich aluminum material to obtain positive and negative electrode mixed powder.

[0009] In step A2, the lithium vapor is collected as solid lithium metal using a condenser.

[0010] In step A3, the grinding fluid used in the wet grinding includes anhydrous ethanol; Preferably, the mass ratio of the alloy particles to anhydrous ethanol is 0.1-0.5:1; Preferably, the magnetic alloy is a Ni-Co-Mn alloy.

[0011] The grinding fluid also includes 4-dodecyl-2-mercaptobenzothiazole; Preferably, the 4-dodecyl-2-mercaptobenzothiazole is 0.5-2.0 wt% of the copper mass in the alloy.

[0012] The sulfur-containing gas generated in step A1 reacts with the calcium-containing slurry to produce calcium sulfate.

[0013] This invention also proposes a special equipment for low-temperature, acid-free closed-loop recycling of all-solid-state batteries. The equipment includes a low-temperature chamber, a shear crusher, a vacuum sublimation furnace, a dry magnetic separation belt conveyor, a high-speed shear stripper, a multi-stage cold trap, a carbothermic reduction rotary furnace, and a condenser collector. Preferably, the high-speed shearing and peeling machine has a rotation speed of ≥8000 rpm; Preferably, the condenser collector includes a rotating condenser plate; More preferably, the temperature of the rotating condenser is -20±5℃.

[0014] Beneficial effects of this invention: (1) The entire recycling process of this invention is acid-free and free of chemicals. ,none Emissions comply with EU Battery Regulation 2027 requirements; (2) The total metal recovery rate of this invention is ≥95%, the lithium recovery rate is ≥93%, and the sulfide electrolyte recycling rate is ≥90%; (3) The energy consumption of this invention is reduced by 40% compared with the traditional pyrometallurgical method, and the equipment investment payback period is less than 3 years; (4) The device of the present invention can be modularized, with a single line processing capacity of 0.5–2 GWh / year, and can be flexibly combined according to the scale of retired batteries. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the process flow of the present invention; Figure 2 This is the general layout diagram of the fully automated dismantling-sorting-regeneration device; Figure 3 This is a cross-sectional view of the integrated vacuum furnace-cold trap structure. Figure 4 This is a schematic diagram of a carbothermic reduction-lithium vapor condensation system. Detailed Implementation

[0016] To facilitate understanding of the present invention, a more comprehensive description will be given below with reference to specific embodiments. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and complete understanding of the disclosure of the present invention.

[0017] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

[0018] The technical solution of the present invention will now be described more clearly and completely with reference to specific embodiments and comparative examples.

[0019] Example 1 This embodiment proposes a low-temperature, acid-free, closed-loop recycling method for all-solid-state batteries, as detailed below: S1. In a low-temperature chamber filled with an inert, dry atmosphere (oxygen content controlled at 3%, moisture content controlled at 100ppm), 100kg of retired sulfide-based all-solid-state pouch cells (rated capacity 100Ah, energy density 360Wh·kg⁻¹) were tested. -1 The entire material is pre-cooled to -40°C, and then mechanically crushed to obtain crushed material with a particle size of <10mm, thus avoiding electrolyte hydrolysis. S2. Place the crushed material in a vacuum sublimation furnace at a temperature of 270°C and a pressure of 80Pa to sublimate the sulfide electrolyte and collect it in a multi-stage cold trap. The cold trap temperature should be controlled at -40±5°C. After vacuum sublimation for 60 minutes, 21.3 kg of the material is obtained. The recovery rate of sulfide electrolyte was 93.0%; S3. The crushed material after vacuum sublimation is magnetically separated using a dry magnetic separator belt conveyor to obtain ferromagnetic current collector fragments and copper-aluminum rich material (Cu: 6.8kg, Al: 4.1kg). S4. The positive and negative electrode sheets are separated from the solid electrolyte ceramic sheet by a high-speed shearing and peeling machine (speed = 8000 rpm) to obtain 48.7 kg of positive and negative electrode mixed powder. S5. Mix the positive and negative electrode powder with graphite powder at a C / O molar ratio of 1.2:1, place the mixture in a carbothermic reduction rotary furnace, and heat at 700°C. After reduction for 30 minutes in an atmosphere, the metal oxide was reduced to alloy particles. It is reduced by carbon to metallic lithium vapor; S6. Collect lithium vapor using a lithium metal condenser. The temperature of the rotating condenser is -20±5°C, yielding 3.1 kg of lithium metal. The lithium metal collection rate is 98.2%, and the purity of the lithium metal is 99.7%. S7. Ni-Co-Mn-Cu alloy particles were wet-milled with anhydrous ethanol at a mass ratio of 0.2:1 at a speed of 150 rpm for 2 hours. The particle size of the wet-milled metal particles was <50 μm. Subsequently, they were separated by magnetic separation to obtain Cu (mass: 2.9 kg, purity: 92.7%) and Ni-Co-Mn alloy (mass: 17.4 kg, purity: 93.2%). The Ni-Co-Mn alloy can be directly used for precursor synthesis. S8. The sulfur-containing tail gas from steps S2 and S5 is then... The slurry absorbs and generates 5.2 kg of CaSO4, achieving zero emissions of sulfur-containing gases, and calcium sulfate can be directly used as a building material additive. S9. The previously collected sulfide electrolyte is placed in a zirconium dioxide ball mill jar with a ball-to-material ratio of 20:1. After sealing and vacuuming the jar, it is transferred to a planetary ball mill for ball milling at a speed of 400 rpm for 4 hours. The powder is then pressed into shape under a pressure of 100 MPa and placed in a sealed quartz tube for annealing at 160°C for 2 hours at a heating rate of 2°C / min. The resulting product is regenerated into a solid electrolyte sheet with a recycling rate of ≥90%.

[0020] Example 2 This embodiment proposes a low-temperature, acid-free, closed-loop recycling method for all-solid-state batteries, as detailed below: S1. In a low-temperature chamber filled with an inert, dry atmosphere (oxygen content controlled at 3%, moisture content controlled at 100ppm), 100kg of retired sulfide-based all-solid-state pouch cells (rated capacity 100Ah, energy density 360Wh·kg⁻¹) were tested. -1 The entire material is pre-cooled to -40°C, and then mechanically crushed to obtain crushed material with a particle size of <10mm, thus avoiding electrolyte hydrolysis. S2. The crushed material is placed in a vacuum sublimation furnace at a temperature of 250°C and a pressure of 100Pa to sublimate the sulfide electrolyte and collect it in a multi-stage cold trap. The temperature of the cold trap should be controlled at -40±5°C. After vacuum sublimation for 40 minutes, 21.1 kg of Li6PS5Cl is obtained, and the recovery rate of the sulfide electrolyte is 92.1%. S3. The crushed material after vacuum sublimation is magnetically separated using a dry magnetic separator belt conveyor to obtain ferromagnetic current collector fragments and copper-aluminum rich material (Cu: 6.75kg, Al: 4.13kg). S4. The positive and negative electrode sheets are separated from the solid electrolyte ceramic sheet by a high-speed shearing and peeling machine (speed = 8500 rpm) to obtain 47.9 kg of positive and negative electrode mixed powder; S5. Mix the positive and negative electrode powder with graphite powder at a C / O molar ratio of 1.2:1, place the mixture in a carbothermic reduction rotary furnace, and heat at 800°C. After reduction for 30 minutes in an atmosphere, the metal oxide was reduced to alloy particles. It is reduced by carbon to metallic lithium vapor; S6. Collect lithium vapor using a lithium metal condenser. The temperature of the rotating condenser is -20±5°C, yielding 3.1 kg of lithium metal. The lithium metal collection rate is 98.2%, and the purity of the lithium metal is 99.6%. S7. Ni-Co-Mn-Cu alloy particles were wet-milled with anhydrous ethanol at a mass ratio of 0.3:1 at a speed of 180 rpm for 1.5 h. The particle size of the wet-milled metal particles was <50 μm. Subsequently, they were separated by magnetic separation to obtain Cu (mass: 2.85 kg, purity: 93.3%) and Ni-Co-Mn alloy (mass: 17.3 kg, purity: 92.1%). The Ni-Co-Mn alloy can be directly used for precursor synthesis. S8. The sulfur-containing tail gas from steps S2 and S5 is then... The slurry absorbed and generated 5.2 kg of CaSO4; S9. The previously collected sulfide electrolyte is placed in a zirconium dioxide ball mill jar with a ball-to-material ratio of 20:1. After sealing and vacuuming the jar, it is transferred to a planetary ball mill for ball milling at a speed of 400 rpm for 4 hours. The powder is then pressed into shape under a pressure of 100 MPa and placed in a sealed quartz tube for annealing at 160°C for 2 hours at a heating rate of 2°C / min. The resulting product is regenerated into a solid electrolyte sheet with a recycling rate of ≥90%.

[0021] Example 3 This embodiment proposes a low-temperature, acid-free, closed-loop recycling method for all-solid-state batteries, as detailed below: S1. In a low-temperature chamber filled with an inert, dry atmosphere (oxygen content controlled at 3%, moisture content controlled at 100ppm), 100kg of retired sulfide-based all-solid-state pouch cells (rated capacity 100Ah, energy density 360Wh·kg⁻¹) were tested. -1 The entire material is pre-cooled to -40°C, and then mechanically crushed to obtain crushed material with a particle size of <10mm, thus avoiding electrolyte hydrolysis. S2. Place the crushed material in a vacuum sublimation furnace at a temperature of 300°C and a pressure of less than 100 Pa to sublimate the sulfide electrolyte, which is then collected in a multi-stage cold trap. The cold trap temperature should be controlled at -40±5°C. After vacuum sublimation for 90 minutes, 21.4 kg of [material name missing] is obtained. The recovery rate of sulfide electrolyte was 93.5%; S3. The crushed material after vacuum sublimation is magnetically separated using a dry magnetic separator belt conveyor to obtain ferromagnetic current collector fragments and copper-aluminum rich material (Cu: 6.8kg, Al: 4.1kg). S4. The positive and negative electrode sheets are separated from the solid electrolyte ceramic sheet by a high-speed shearing and peeling machine (speed = 9000 rpm) to obtain 48.7 kg of positive and negative electrode mixed powder. S5. Mix the positive and negative electrode powder with graphite powder at a C / O molar ratio of 1.2:1, place the mixture in a carbothermic reduction rotary furnace, and heat at 700°C. After reduction for 30 minutes in an atmosphere, the metal oxide was reduced to alloy particles. It is reduced by carbon to metallic lithium vapor; S6. Collect lithium vapor using a lithium metal condenser. The temperature of the rotating condenser is -20±5°C, yielding 3.11 kg of lithium metal. The lithium metal collection rate is 98.5%, and the purity of the lithium metal is 99.7%. S7. Ni-Co-Mn-Cu alloy particles were wet-milled with anhydrous ethanol at a mass ratio of 0.5:1 at a speed of 100 rpm for 3 hours. The particle size of the wet-milled metal particles was <50 μm. Subsequently, they were separated by magnetic separation to obtain Cu (mass: 2.9 kg, purity: 92.3%) and Ni-Co-Mn alloy (mass: 17.4 kg, purity: 92.8%). The Ni-Co-Mn alloy can be directly used for precursor synthesis. S8. The sulfur-containing tail gas from steps S2 and S5 is then... The slurry absorbed and generated 5.2 kg of CaSO4; S9. The previously collected sulfide electrolyte is placed in a zirconium dioxide ball mill jar with a ball-to-material ratio of 20:1. After sealing and vacuuming the jar, it is transferred to a planetary ball mill for ball milling at a speed of 400 rpm for 4 hours. The powder is then pressed into shape under a pressure of 100 MPa and placed in a sealed quartz tube for annealing at 160°C for 2 hours at a heating rate of 2°C / min. The resulting product is regenerated into a solid electrolyte sheet with a recycling rate of ≥90%.

[0022] Example 4 This embodiment proposes a low-temperature, acid-free, closed-loop recycling method for all-solid-state batteries, as detailed below: S1. In a low-temperature chamber filled with an inert, dry atmosphere (oxygen content controlled at 3%, moisture content controlled at 100ppm), 100kg of retired sulfide-based all-solid-state pouch cells (rated capacity 100Ah, energy density 360Wh·kg⁻¹) were tested. -1 The entire material is pre-cooled to -40°C, and then mechanically crushed to obtain crushed material with a particle size of <10mm, thus avoiding electrolyte hydrolysis. S2. Place the crushed material in a vacuum sublimation furnace at a temperature of 270°C and a pressure of 80Pa to sublimate the sulfide electrolyte and collect it in a multi-stage cold trap. The cold trap temperature should be controlled at -40±5°C. After vacuum sublimation for 60 minutes, 21.3 kg of the material is obtained. The recovery rate of sulfide electrolyte was 93.0%; S3. The crushed material after vacuum sublimation is magnetically separated using a dry magnetic separator belt conveyor to obtain ferromagnetic current collector fragments and copper-aluminum rich material (Cu: 6.8kg, Al: 4.1kg). S4. The positive and negative electrode sheets are separated from the solid electrolyte ceramic sheet by a high-speed shearing and peeling machine (speed = 8000 rpm) to obtain 48.7 kg of positive and negative electrode mixed powder. S5. Mix the positive and negative electrode powder with graphite powder at a C / O molar ratio of 1.2:1, place the mixture in a carbothermic reduction rotary furnace, and heat at 700°C. After reduction for 30 minutes in an atmosphere, the metal oxide was reduced to alloy particles. It is reduced by carbon to metallic lithium vapor; S6. Collect lithium vapor using a lithium metal condenser. The temperature of the rotating condenser is -20±5°C, yielding 3.1 kg of lithium metal. The lithium metal collection rate is 98.2%, and the purity of the lithium metal is 99.7%. S7. Ni-Co-Mn-Cu alloy particles, anhydrous ethanol, and 4-dodecyl-2-mercaptobenzothiazole were wet-milled at a mass ratio of 0.2:1:0.003. The wet milling speed was 150 rpm and the wet milling time was 2 h. The particle size of the metal particles after wet milling was <50 μm. Subsequently, Cu and Ni-Co-Mn alloy particles were separated by magnetic separation to obtain Cu (mass: 2.85 kg, purity: 94.5%) and Ni-Co-Mn alloy (mass: 17.1 kg, purity: 94.1%), respectively. The Ni-Co-Mn alloy can be directly used for precursor synthesis. The preparation method of 4-dodecyl-2-mercaptobenzothiazole is as follows: Under a nitrogen atmosphere, 4-dodecylaniline, carbon disulfide, potassium sulfate, and cuprous iodide were dissolved in anhydrous ethanol at a molar ratio of 1:2:0.5:0.1. After the raw materials were completely dissolved, the mixture was reacted at 105°C for 10 h. The reactants were then cooled to 25°C, and 1 mol / L dilute hydrochloric acid was added and stirred for 20 min. The reactants were then extracted twice with dichloromethane to obtain an organic phase containing 4-dodecyl-2-mercaptobenzothiazole. The organic phase was then dried, evaporated under reduced pressure, and finally separated by column chromatography (400 mesh silica gel). Gradient elution with petroleum ether and ethyl acetate (8:1-2:1) yielded 4-dodecyl-2-mercaptobenzothiazole.

[0023] S8. The sulfur-containing tail gas from steps S2 and S5 is absorbed by Ca(OH)2 slurry to generate 5.2 kg of CaSO4, achieving zero emission of sulfur-containing gas, and calcium sulfate can be directly used as a building material additive. S9. The previously collected sulfide electrolyte is placed in a zirconium dioxide ball mill jar with a ball-to-material ratio of 20:1. After sealing and vacuuming the jar, it is transferred to a planetary ball mill for ball milling at a speed of 400 rpm for 4 hours. The powder is then pressed into shape under a pressure of 100 MPa and placed in a sealed quartz tube for annealing at 160°C for 2 hours at a heating rate of 2°C / min. The resulting product is regenerated into a solid electrolyte sheet with a recycling rate of ≥90%.

[0024] In this invention, the equipment involved in S1-S9 in each embodiment is a fully automated disassembly-sorting-regeneration device. The PLC control system is interconnected with the MES network to achieve batch tracking and process adaptation. The overall layout diagram is as follows: Figure 2 As shown; the sublimation-condensation involved in S2 is achieved through an integrated vacuum furnace-cold trap structure, as follows. Figure 3 As shown; the recovery of metallic lithium in S5 and S6 is achieved through a carbothermic reduction-lithium vapor condensation system, as follows: Figure 4 As shown.

[0025] Comparative Example 1 This comparative example proposes a method for low-temperature, acid-free closed-loop recycling of all-solid-state batteries, which is the same as that in Example 1, except that step S5 is replaced with the existing water leaching lithium extraction method, specifically: "Take 100g of pyrolysis residue, mix it with water at a liquid-to-solid ratio of 14mL / g, set the temperature at 50℃ and the time at 160min for water leaching reaction, and then obtain water leaching liquid and water leaching residue by solid-liquid separation".

[0026] In Comparative Example 1, water leaching for lithium extraction generates a large amount of waste liquid that is difficult to treat, and the lithium recovery rate is only 92%, which is far lower than the 98% of the present invention.

[0027] Comparative Example 2 This comparative example proposes a method for low-temperature, acid-free closed-loop recycling of all-solid-state batteries, which is the same as that in Example 1, except that in step S7, "Ni-Co-Mn-Cu alloy particles and anhydrous ethanol are wet-milled at a mass ratio of 0.2:1" is replaced with "Ni-Co-Mn-Cu alloy particles and deionized water are wet-milled at a mass ratio of 0.2:1".

[0028] In Comparative Example 2, the moisture reacts with residual sulfides. Reaction generation There are security risks.

[0029] Comparative Example 3 This comparative example proposes a method for low-temperature, acid-free closed-loop recycling of all-solid-state batteries, which is the same as that in Example 4, except that “4-dodecyl-2-mercaptobenzothiazole” in step S7 is replaced with “2-mercaptobenzothiazole”.

[0030] In Comparative Example 3, the final obtained Cu (mass: 2.83 kg, purity: 93.2%) and Ni-Co-Mn alloy (mass: 17.3 kg, purity: 93.6%) had similar purity to Example 1. This is because 2-mercaptobenzothiazole lacks long carbon chains, and the copper particles adsorbed with 2-mercaptobenzothiazole do not generate strong interactions. The tiny copper particles cannot aggregate well, and the copper is dispersed in the nickel-cobalt-manganese alloy. After magnetic separation, the purity of the two types of alloys is not greatly improved. If the wet grinding time is too long, it will interfere with the subsequent magnetic separation.

[0031] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A method for low-temperature, acid-free closed-loop recycling of all-solid-state batteries, characterized in that, Includes the following steps: A1. The positive and negative electrode mixed powders are reacted with a reducing agent to obtain alloy particles and lithium vapor, respectively. A2. Collect lithium vapor into solid metallic lithium; A3. After wet grinding of the alloy particles, magnetic separation was performed to obtain Cu and magnetic alloy respectively.

2. The method for low-temperature, acid-free closed-loop recycling of all-solid-state batteries according to claim 1, characterized in that, In step A1, the reducing agent is graphite powder; Preferably, the C / O molar ratio of the positive and negative electrode mixed powder to the graphite powder is 1.2:1; Preferably, the reduction reaction temperature is 700-900℃; Preferably, the reduction reaction time is 20-60 min.

3. The method for low-temperature acid-free closed-loop recycling of solid-state batteries according to claim 1 or 2, characterized in that, Step A1 further includes A1-1, cooling and crushing the all-solid-state battery to obtain a mixture; Preferably, the cooling temperature of the all-solid-state battery is -40°C; Preferably, the particle size of the mixture is <10mm.

4. The method for low-temperature, acid-free closed-loop recycling of all-solid-state batteries according to any one of claims 1-3, characterized in that, Step A1 further includes A1-2, sublimating the mixture under vacuum to obtain a sulfide electrolyte; Preferably, the temperature of the vacuum sublimation is 250-300℃; Preferably, the pressure of the vacuum sublimation is <100 Pa; Preferably, the vacuum sublimation time is 40-90 min; More preferably, the sulfide electrolyte is regenerated into a solid electrolyte sheet through ball milling, cold pressing, and annealing.

5. The method for low-temperature, acid-free closed-loop recycling of all-solid-state batteries according to any one of claims 1-4, characterized in that, Step A1 further includes A1-3, performing magnetic separation on the vacuum sublimated mixture to obtain ferromagnetic current collector and copper-rich aluminum material respectively; Step A1 further includes A1-4, mechanically peeling off the copper-rich aluminum material to obtain positive and negative electrode mixed powder.

6. The method for low-temperature acid-free closed-loop recycling of all-solid-state batteries according to any one of claims 1-5, characterized in that, In step A2, the lithium vapor is collected as solid lithium metal using a condenser.

7. The method for low-temperature, acid-free closed-loop recycling of all-solid-state batteries according to any one of claims 1-6, characterized in that, In step A3, the grinding fluid used in the wet grinding includes anhydrous ethanol; Preferably, the mass ratio of the alloy particles to anhydrous ethanol is 0.1-0.5:1; Preferably, the magnetic alloy is a Ni-Co-Mn alloy.

8. The method for low-temperature acid-free closed-loop recycling of all-solid-state batteries according to claim 7, characterized in that, The grinding fluid also includes 4-dodecyl-2-mercaptobenzothiazole; Preferably, the 4-dodecyl-2-mercaptobenzothiazole is 0.5-2.0 wt% of the copper mass in the alloy.

9. The method for low-temperature acid-free closed-loop recycling of all-solid-state batteries according to any one of claims 1-8, characterized in that, The sulfur-containing gas generated in step A1 reacts with the calcium-containing slurry to produce calcium sulfate.

10. A dedicated device for low-temperature, acid-free closed-loop recycling of all-solid-state batteries, characterized in that, The equipment includes a cryogenic chamber, a shear crusher, a vacuum sublimation furnace, a dry magnetic separation belt conveyor, a high-speed shear stripper, a multi-stage cold trap, a carbothermic reduction rotary furnace, and a condenser collector; Preferably, the high-speed shearing and peeling machine has a rotation speed of ≥8000 rpm; Preferably, the condenser collector includes a rotating condenser plate; More preferably, the temperature of the rotating condenser is -20±5℃.

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