Recycling method of waste lithium ion battery, battery and power utilization device

Abstract

The invention discloses a waste lithium ion battery recycling method, a battery and a power utilization device.The recycling method comprises the steps that waste lithium ion batteries are classified and disassembled, and at least one of positive electrode waste powder and negative electrode waste powder is obtained; wherein at least one of the obtained positive electrode waste powder and negative electrode waste powder is repaired. In the embodiment of the invention, each part of the waste lithium ion battery is disassembled in a classified manner, so that each separated part can be recycled according to each attribute characteristic, and the maximization of resource utilization is realized. According to the method, at least one of the positive electrode waste powder and the negative electrode waste powder is independently separated and repaired, so that high-value components of the waste lithium ion battery are fully recycled, and reasonable recycling of resources is realized.

Description

Technical Field

[0001] The present invention relates to the technical field of batteries, and in particular to a method for recycling waste lithium-ion batteries, a battery and an electrical device. Background Art

[0002] The above statements of battery are only used to provide background information related to the present application and do not necessarily constitute prior art.

[0003] In recent years, the new energy market has continued to expand, and power battery sales have grown rapidly. Power batteries typically have a service life of five to eight years. Failure to effectively dispose of expired batteries not only causes serious environmental pollution but also wastes significant amounts of valuable metals (such as lithium, manganese, nickel, and cobalt). Properly handling the growing supply of spent lithium-ion batteries presents both a significant opportunity and a significant challenge. Recycling spent lithium-ion batteries is crucial for reducing environmental pollution and alleviating resource pressures. Summary of the Invention

[0004] The main technical problem solved by this application is how to properly deal with the growing amount of waste lithium-ion batteries.

[0005] In a first aspect, an embodiment of the present application provides a method for recycling waste lithium-ion batteries, comprising: Classifying and disassembling waste lithium-ion batteries to obtain at least one of positive electrode waste powder and negative electrode waste powder; Wherein, at least one of the obtained positive electrode waste powder and negative electrode waste powder is repaired.

[0006] In the embodiments of this application, by disassembling the various parts of waste lithium-ion batteries according to their respective properties, the separated components can be recycled and reused according to their respective properties, thereby maximizing resource utilization. By isolating at least one of the waste positive electrode powder and the waste negative electrode powder and repairing them, the high-value components of the waste lithium-ion batteries can be fully reused, achieving rational resource reuse.

[0007] In some embodiments, the steps of repairing the waste positive electrode powder include: Screening out first waste positive electrode powder from waste positive electrode powder according to a first preset screening condition, and sintering the first waste positive electrode powder; And / or, according to the second preset screening condition, second waste positive electrode powder is screened out from the waste positive electrode powder, and the second waste positive electrode powder is wet-processed.

[0008] In the embodiments of the present application, by classifying the positive electrode waste powder and then performing targeted repairs based on the conditions of each type of positive electrode waste powder, the repair process of the positive electrode waste powder with high recovery value can recover sufficient products, be simple in means, and be easy to implement, introduce few pollutants, and be highly environmentally friendly, thereby increasing the value of recycling and reusing waste lithium-ion batteries and reducing the environmental pollution caused by waste lithium-ion batteries. Among them, the first positive electrode waste powder is sintered so that the positive electrode waste powder that still has a relatively high battery capacity can be re-formed into commercially viable positive electrode powder, and the repair method is simpler, more environmentally friendly, and has a high recovery rate. The second positive electrode waste powder is wet-processed so that the positive electrode waste powder with a relatively low battery capacity can obtain its valuable metals, thereby increasing its utilization value.

[0009] In some embodiments, the first preset screening condition includes: the waste positive electrode powder and the unused positive electrode powder have at least five XRD characteristic peaks with the same diffraction angle, and / or at least 30% by weight of the particles of the waste positive electrode powder have only cracks or are intact on their surfaces; And / or, the second preset screening condition includes: the positive electrode waste powder and the unused positive electrode powder have at most three XRD characteristic peaks with the same diffraction angle, and / or at least 10% by weight of the particles of the first positive electrode waste powder are surface crushed.

[0010] In the embodiments of the present application, by performing XRD and / or ICP testing on the positive electrode waste powder, classifying and screening the positive electrode waste powder, and performing targeted repair on the positive electrode waste powder according to the screening results, the value of recycling and reuse of waste lithium-ion batteries can be increased and the pollution of waste lithium-ion batteries to the environment can be reduced.

[0011] In some embodiments, the step of sintering the first positive electrode waste powder includes: Mixing the first cathode waste powder with a lithium supplement agent to obtain a cathode mixture; The positive electrode mixture is sintered to obtain a first positive electrode repair material.

[0012] In an embodiment of the present application, a positive electrode mixture obtained by mixing a first positive electrode waste powder with a lithium supplement is sintered to promote the grain development of the first positive electrode waste powder, forming a new positive electrode repair material that can be commercialized again. The battery capacity of the obtained positive electrode repair material can be restored to more than 95% of the battery capacity of the positive electrode waste powder when it was not used. The obtained first positive electrode repair material can be downgraded and recycled for reuse, for example, from the battery positive electrode material of an electric vehicle to the battery positive electrode material of an electric motorcycle, thereby increasing the utilization value of the positive electrode waste powder. The sintering process is simple and easy to implement, and has an advantage in repair cost. It should be noted that in some cases, irreversible damage has occurred in the structure of the positive electrode waste powder. Even if a lithium supplement is added and sintering is performed, it cannot be completely restored to the battery performance when the positive electrode waste powder was not used.

[0013] In some embodiments, the step of sintering the positive electrode mixture includes: sintering the positive electrode mixture at a first preset temperature for a first preset time; Wherein, the first preset temperature is 800° C.-900° C., and / or the first preset time is 6 hours-12 hours.

[0014] In the embodiment of the present application, by sintering the positive electrode mixture, the first positive electrode waste mixture can be repaired into a new positive electrode repair material that can be commercially used again, thereby improving the utilization value of the positive electrode waste powder and reducing the production cost of the battery.

[0015] In some embodiments, the lithium supplement comprises at least one of lithium hydroxide, lithium nitrate, and lithium carbonate.

[0016] In the embodiments of the present application, the lithium deficiency of the first positive electrode waste powder is supplemented by the provided lithium supplement agent to increase the lithium content of the first positive electrode repair material, so that the first positive electrode repair material can be used in the battery again. The battery formed not only has a high energy density and high commercial value, but also has a low production cost. At the same time, it is also beneficial to reduce the pollution of the environment and the waste of resources caused by waste batteries.

[0017] In some embodiments, the step of mixing the first cathode waste powder with the lithium supplement agent includes: ball milling the first cathode waste powder; Among them, the average particle size D of the first cathode waste powder after ball milling is 50 ≦100μm.

[0018] In the embodiment of the present application, by ball milling the first positive electrode waste powder, the grain size of the first positive electrode waste powder can be effectively reduced, and the dispersion uniformity of the first positive electrode waste powder can be improved. In the subsequent sintering process, it is also beneficial to reduce the lattice defects of the sintered product and improve the density of the sintered product, thereby improving the battery performance of the sintered product.

[0019] In some embodiments, the step of wet treating the second cathode waste powder includes: Adding the second cathode waste powder to a leaching agent and a reducing agent at a second preset temperature, and immersing for a second preset time to obtain a second cathode repair material; Wherein, the second preset temperature is 80℃-100℃; and / or, the leaching agent comprises at least one of sulfuric acid, acetic acid, tartaric acid, and oxalic acid; and / or, the reducing agent comprises at least one of hydrogen peroxide, sulfite, and thiosulfate; And / or, the second preset duration is 0.5h-5h.

[0020] In the embodiment of the present application, by wet processing the second positive electrode waste powder, the valuable metals in the second positive electrode waste powder can be fully recovered and reused, thereby improving the utilization value of the second positive electrode waste powder and reducing the production cost of the battery.

[0021] In some embodiments, the step of repairing the waste negative electrode powder includes: Mixing the negative electrode waste powder with a carbon source to obtain a negative electrode mixture; The negative electrode mixture is sintered to obtain negative electrode repair powder.

[0022] In the embodiments of the present application, the negative electrode mixture obtained by mixing the negative electrode waste powder and the carbon source is sintered to achieve deep impurity removal of the negative electrode waste powder, and the surface of the negative electrode material after impurity removal is coated with new carbon material, thereby improving the recovery value of the obtained negative electrode repair powder. The sintering process is simple and less polluting, and has more advantages in repair costs.

[0023] In some embodiments, the step of sintering the negative electrode mixture includes: sintering the negative electrode mixture at a third preset temperature for a third preset time; Among them, the third preset temperature is 2200℃-3000℃; And / or, the third preset duration is 20 hours to 70 hours.

[0024] In the embodiments of the present application, by sintering the negative electrode mixture, the waste negative electrode mixture can be repaired into a new negative electrode repair material that can be commercially used again, thereby increasing the utilization value of the waste negative electrode powder and reducing the production cost of the battery.

[0025] In some embodiments, the carbon source includes at least one of artificial graphite and natural graphite; Optionally, the mass ratio of the negative electrode waste powder to the carbon source is 6-8:2-4.

[0026] In the embodiments of the present application, the negative electrode waste powder is deeply decontaminated by the provided carbon source, and the surface of the negative electrode material after decontamination is coated with new carbon material, so that the negative electrode repair material can be reused in the battery, thereby improving the reuse value of the negative electrode waste powder, reducing the production cost of the battery, and at the same time reducing the pollution of the environment and the waste of resources caused by waste batteries.

[0027] In some embodiments, the steps of classifying and disassembling waste lithium-ion batteries include: Disassemble the waste lithium-ion batteries to obtain the shell and bare cells; The bare battery cell is disassembled to obtain waste coating film, waste positive electrode sheet, waste negative electrode sheet, residual electrolyte and waste isolation film; At least one of the waste positive electrode sheets and the waste negative electrode sheets is subjected to a powder removal treatment.

[0028] In the embodiments of the present application, waste lithium-ion batteries are recycled and reused to the maximum extent possible by classifying and disassembling the waste lithium-ion batteries and then performing targeted treatment on each of the disassembled parts.

[0029] In some embodiments, the step of removing powder from the waste positive electrode sheets includes: At a fourth preset temperature, washing the waste positive electrode sheets with a cleaning solvent for a fourth preset time, so that the waste positive electrode sheets are separated into a positive electrode current collector and a waste positive electrode powder; Among them, the fourth preset temperature is 20℃-30℃; and / or, the fourth preset duration is 2h-4h; And / or, the cleaning solvent includes deionized water.

[0030] In the embodiment of the present application, by de-powdering the waste positive electrode sheets, the waste positive electrode powder and the positive electrode current collector can be fully separated so that they can be recycled and reused separately, and both can fully realize their reuse value.

[0031] In some embodiments, after the step of de-powdering the waste positive electrode sheets, the step of removing impurities from the waste positive electrode powder is further included, including: At a fifth preset temperature, stirring the waste positive electrode powder with an acidic solution for a fifth preset time; Among them, the fifth preset temperature is 80℃-90℃; and / or, the acidic solution includes at least one of sulfuric acid, hydrochloric acid, and phosphoric acid; and / or, the concentration of the acidic solution is 0.1 mol / L-1.0 mol / L; and / or, the stirring speed is 15 rpm to 50 rpm; And / or, the fifth preset duration is 4 hours to 6 hours.

[0032] In the embodiments of the present application, the positive electrode waste powder is subjected to impurity removal treatment to reduce the impact of impurities on the positive electrode waste powder, improve the performance of the positive electrode waste powder obtained after impurity removal, and thereby improve the reuse value of the obtained positive electrode waste powder.

[0033] In some embodiments, the step of removing powder from the waste negative electrode sheets includes: At a sixth preset temperature, flushing the waste negative electrode sheets with water for a sixth preset time, so that the waste negative electrode sheets are separated into a negative electrode current collector and a waste negative electrode powder; Among them, the sixth preset temperature is 20℃-30℃; And / or, the sixth preset duration is 2 hours to 4 hours.

[0034] In the embodiment of the present application, by de-powdering the waste negative electrode sheets, the waste negative electrode powder and the negative electrode current collector can be fully separated so that they can be recycled and reused separately, and both can fully realize their reuse value.

[0035] In some embodiments, after the step of de-powdering the waste negative electrode sheets, the step of removing impurities from the waste negative electrode powder is further included, including: At a seventh preset temperature, stirring the negative electrode waste powder with an acidic solution for a seventh preset time; Among them, the seventh preset temperature is 80℃-90℃; and / or, the acidic solution includes at least one of sulfuric acid, hydrochloric acid, and phosphoric acid; and / or, the concentration of the acidic solution is 0.1 mol / L-1.0 mol / L; and / or, the stirring speed is 20 rpm to 60 rpm; And / or, the seventh preset duration is 4 hours to 6 hours.

[0036] In the embodiments of the present application, the negative electrode waste powder is subjected to impurity removal treatment to reduce the impact of impurities on the negative electrode waste powder, improve the performance of the negative electrode waste powder obtained after impurity removal, and thereby improve the reuse value of the obtained negative electrode waste powder.

[0037] In some embodiments, the step of repairing the residual electrolyte includes: distilling the residual electrolyte to obtain a distillation product; Batch blending of distillation products; Add bulking agent to the mixed batch of distilled products.

[0038] In the embodiments of the present application, the residual electrolyte is repaired so that the obtained repair product can be commercially used as a battery electrolyte again, thereby increasing the utilization value of the residual electrolyte, reducing the production cost of the battery, and reducing the pollution of the residual electrolyte to the environment.

[0039] In some embodiments, the step of adding a filler to the batch mixed distilled product comprises: measuring the missing component and the amount of the missing component in the batch processed distillation product relative to unused electrolyte; Based on the missing component and the missing amount of the missing component, the composition of the filler is determined and the amount of the filler to be added is calculated.

[0040] In the embodiments of the present application, appropriate fillers are added based on the measurement of the missing components and the missing amounts of the distilled product to supplement the missing components in the distilled product, thereby optimizing the performance of the repaired product to meet the expected requirements.

[0041] In some embodiments, the step of disassembling the waste lithium-ion batteries includes: Discharge the used lithium-ion batteries; Optionally, discharge the used lithium-ion battery to below 1V.

[0042] In the embodiments of the present application, by discharging the waste lithium-ion batteries before disassembling them, the safety performance of the waste lithium-ion batteries is improved and the occurrence of accidents is reduced.

[0043] In a second aspect, an embodiment of the present application provides a battery, which includes a recycled product of any of the waste lithium-ion battery recycling methods provided in the first aspect.

[0044] In a third aspect, an embodiment of the present application provides an electrical device, which includes the battery provided in the second aspect, and the battery is used to provide electrical energy. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0046] Figure 1 A schematic structural diagram of a vehicle provided in some embodiments of the present application; Figure 2 A schematic diagram of the exploded structure of a battery provided in some embodiments of the present application; Figure 3 A schematic diagram of the exploded structure of a battery cell provided in some embodiments of the present application; Figure 4 A schematic flow chart of a method for recycling waste lithium-ion batteries provided in an embodiment of the present application.

[0047] Description of Figure Numbers: 1000-vehicle, 100-battery, 200-controller, 300-motor, 10-housing, 20-battery cell, 11-first part, 12-second part, 21-end cover, 22-housing, 23-electrode assembly, 21a-electrode terminal, 23a-tab. DETAILED DESCRIPTION

[0048] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0049] The terms "first," "second," and "third" in this application are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features identified. Therefore, features identified as "first," "second," or "third" may explicitly or implicitly include at least one of such features. In the description of this application, "plurality" means at least two, for example, two, three, etc., unless otherwise specifically defined. All directional designations in the embodiments of this application (such as up, down, left, right, front, back, etc.) are intended only to illustrate the relative positional relationships and movement of components in a specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional designations will also change accordingly. Furthermore, the terms "including," "having," and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product, or apparatus comprising a series of steps or elements is not limited to the listed steps or elements but may optionally include steps or elements not listed, or may optionally include other steps or elements inherent to such process, method, product, or apparatus.

[0050] References herein to "embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0051] Currently, the main industrial recycling method for spent lithium-ion batteries is to mechanically crush the spent lithium-ion batteries and then use pyrometallurgical, hydrometallurgical, or combined pyrometallurgical and hydrometallurgical methods to recover the valuable metal elements from the spent lithium-ion batteries. Pyrometallurgical recycling involves heat treatment to recover the waste materials, a relatively simple process, but suffers from low recovery rates and environmental pollution. Wet recycling involves low-temperature leaching, purification, and separation to recycle battery materials, but the recycling process is complex and produces a large number of intermediate byproducts.

[0052] However, among the used lithium-ion batteries, such as those discarded from electric vehicles, a large portion of the batteries still have a capacity of more than 70% of the original capacity and are in good appearance. Directly mechanically crushing and recycling such used lithium-ion batteries would be a waste of resources.

[0053] In summary, in order to solve the above problems, the embodiments of the present application provide a green recycling method for waste lithium-ion batteries, which increases the return rate of recycled products and achieves efficient utilization of waste lithium-ion batteries.

[0054] The materials recovered from the waste lithium-ion battery recycling methods disclosed in the embodiments of this application can be used in batteries. The batteries disclosed in the embodiments of this application can be used in electrical devices that use batteries as power sources or in various energy storage systems that use batteries as energy storage elements. Electrical devices may include, but are not limited to, mobile phones, tablets, laptops, electric toys, power tools, electric vehicles, electric cars, ships, spacecraft, and the like.

[0055] For the convenience of description, the following embodiments are described by taking a vehicle 1000 as an example of an electrical device according to an embodiment of the present application.

[0056] Please refer to Figure 1 , Figure 1 A schematic structural diagram of a vehicle 1000 provided for some embodiments of the present application. The vehicle 1000 may be a fuel vehicle, a gas vehicle or a new energy vehicle. The new energy vehicle may be a pure electric vehicle, a hybrid vehicle or an extended-range vehicle, etc. A battery 100 is provided inside the vehicle 1000. The battery 100 may be provided at the bottom, head or tail of the vehicle 1000. The battery 100 may be used to power the vehicle 1000. For example, the battery 100 may serve as an operating power source for the vehicle 1000. The vehicle 1000 may further include a controller 200 and a motor 300. The controller 200 is used to control the battery 100 to power the motor 300, for example, to meet the power requirements for starting, navigating and driving the vehicle 1000.

[0057] In some embodiments of the present application, the battery 100 can serve not only as an operating power source for the vehicle 1000, but also as a driving power source for the vehicle 1000, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000.

[0058] Please refer to Figure 2 , Figure 2This is a schematic diagram of the exploded structure of a battery 100 provided in some embodiments of the present application. The battery 100 includes a housing 10 and a battery cell 20, with the battery cell 20 housed within the housing 10. The housing 10 is used to provide a storage space for the battery cell 20 and can have various structures. In some embodiments, the housing 10 can include a first portion 11 and a second portion 12, which overlap each other and together define a storage space for the battery cell 20. The second portion 12 can be a hollow structure with one end open. The first portion 11 can be a plate-like structure, with the first portion 11 overlapping the open side of the second portion 12, so that the first portion 11 and the second portion 12 together define a storage space. The first portion 11 and the second portion 12 can also be hollow structures with one end open, with the open side of the first portion 11 overlapping the open side of the second portion 12. Of course, the housing 10 formed by the first portion 11 and the second portion 12 can have various shapes, such as a cylinder, a rectangular parallelepiped, etc.

[0059] In the battery 100, there may be multiple battery cells 20, and the multiple battery cells 20 may be connected in series, in parallel, or in a hybrid connection. A hybrid connection refers to a combination of series and parallel connections among the multiple battery cells 20. The multiple battery cells 20 may be directly connected in series, in parallel, or in a hybrid connection, and then the entire battery cell 20 may be housed within the housing 10. Alternatively, the battery 100 may be constructed by first connecting multiple battery cells 20 in series, in parallel, or in a hybrid connection to form a battery module, which is then connected in series, in parallel, or in a hybrid connection to form a complete battery module, and then housed within the housing 10. The battery 100 may also include other structures, such as a busbar assembly for electrically connecting the multiple battery cells 20.

[0060] Each battery cell 20 may be a secondary battery or a primary battery, and may also be a lithium-sulfur battery, a sodium-ion battery, or a magnesium-ion battery, but is not limited thereto. The battery cell 20 may be cylindrical, flat, rectangular, or in other shapes.

[0061] Battery manufacturing methods include laminated and wound types. Laminated batteries offer uniform current collection, low internal resistance, and high specific power. However, to ensure accuracy, they require extremely high mold precision, high equipment investment, and a complex process, resulting in low production efficiency. Wound batteries are simple to manufacture, with moderate equipment precision requirements during the production and assembly processes. They offer high production efficiency and low costs. In terms of performance, wound batteries offer excellent high and low temperature performance, very fast charging, an extremely long lifespan, a stable high output voltage, a sturdy structure, and strong shock resistance.

[0062] Please refer to Figure 3 , Figure 3The following is a schematic diagram of the decomposition structure of a battery cell 20 provided in some embodiments of the present application. A battery cell 20 is the smallest unit that makes up a battery. Figure 3 The battery cell 20 includes an end cap 21, a shell 22, an electrode assembly 23 and other functional components.

[0063] The end cap 21 is a component that covers the opening of the housing 22 to isolate the internal environment of the battery cell 20 from the external environment. The shape of the end cap 21 can be adapted to the shape of the housing 22 to fit the housing 22. Optionally, the end cap 21 can be made of a material with a certain degree of hardness and strength (such as an aluminum alloy). This prevents the end cap 21 from deforming under compression or collision, thereby enhancing the structural strength and safety of the battery cell 20. The end cap 21 can be provided with functional components such as electrode terminals 21a. The electrode terminals 21a can be used to electrically connect to the electrode assembly 23 to transmit or receive electrical energy from the battery cell 20. In some embodiments, the end cap 21 can also be provided with a pressure relief mechanism to release internal pressure when the internal pressure or temperature of the battery cell 20 reaches a threshold. The end cap 21 can be made of a variety of materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, and plastic, and this is not particularly limited in the present embodiments. In some embodiments, an insulating member may be provided inside the end cap 21 to isolate the electrical connection components in the housing 22 from the end cap 21 to reduce the risk of short circuit. For example, the insulating member may be made of plastic, rubber, or the like.

[0064] The housing 22 is a component that cooperates with the end cap 21 to form the internal environment of the battery cell 20. This internal environment can be used to accommodate the electrode assembly 23, electrolyte, and other components. The housing 22 and end cap 21 can be separate components. An opening can be provided in the housing 22, and the end cap 21 is placed over the opening to form the internal environment of the battery cell 20. Alternatively, the end cap 21 and housing 22 can be integrated. Specifically, the end cap 21 and housing 22 can form a common connection surface before other components are inserted into the housing. When the interior of the housing 22 needs to be enclosed, the end cap 21 is placed over the housing 22. The housing 22 can have a variety of shapes and sizes, such as a rectangular parallelepiped, a cylindrical shape, or a hexagonal prism. Specifically, the shape of the housing 22 can be determined based on the specific shape and size of the electrode assembly 23. The housing 22 can be made of a variety of materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and this embodiment of the present application does not impose any particular limitations on this.

[0065] The electrode assembly 23 is a component in the battery cell 100 where electrochemical reactions occur. One or more electrode assemblies 23 may be contained in the housing 22. The electrode assembly 23 is mainly formed by winding or stacking positive and negative electrode sheets, and a separator is usually provided between the positive and negative electrode sheets. The parts of the positive and negative electrode sheets with active materials constitute the main body of the electrode assembly, and the parts of the positive and negative electrode sheets without active materials each constitute a tab 23a. The positive and negative electrode tabs may be located together at one end of the main body or respectively at both ends of the main body. During the charge and discharge process of the battery, the positive active material and the negative active material react with the electrolyte, and the tabs 23a connect the electrode terminals to form a current loop.

[0066] See also Figure 4 , Figure 4 A schematic flow chart of a method for recycling waste lithium-ion batteries provided in an embodiment of the present application.

[0067] First, see Figure 4 , an embodiment of the present application provides a method for recycling waste lithium-ion batteries, comprising: Classifying and disassembling waste lithium-ion batteries to obtain at least one of positive electrode waste powder and negative electrode waste powder; Wherein, at least one of the obtained positive electrode waste powder and negative electrode waste powder is repaired.

[0068] Among them, waste lithium-ion batteries refer to retired lithium-ion batteries. In some embodiments, waste lithium-ion batteries may be batteries whose battery capacity has decayed to 70% or 80% of the factory capacity. In some embodiments, waste lithium-ion batteries may be batteries that have not been used for a long time. For example, waste lithium-ion batteries may be batteries that have not been used for two years. Positive electrode waste powder refers to positive electrode powder obtained by disassembling waste lithium-ion batteries. Negative electrode waste powder refers to negative electrode powder obtained by disassembling waste lithium-ion batteries. Repair refers to improving the use value and economic value of positive electrode waste powder and / or negative electrode waste powder through certain processing means.

[0069] In the embodiments of this application, by disassembling the various parts of waste lithium-ion batteries according to their respective properties, the separated components can be recycled and reused according to their respective properties, thereby maximizing resource utilization. By isolating at least one of the waste positive electrode powder and the waste negative electrode powder and repairing them, the high-value components of the waste lithium-ion batteries can be fully reused, achieving rational resource reuse.

[0070] In some embodiments, the steps of repairing the waste positive electrode powder include: Screening out first waste positive electrode powder from waste positive electrode powder according to a first preset screening condition, and sintering the first waste positive electrode powder; And / or, according to the second preset screening condition, second waste positive electrode powder is screened out from the waste positive electrode powder, and the second waste positive electrode powder is wet-processed.

[0071] The first and / or second preset screening conditions refer to a screening method for classifying waste positive electrode powder. Sintering treatment refers to a method for repairing waste positive electrode powder under high temperature conditions. Wet treatment refers to a method for repairing waste positive electrode powder in a liquid environment.

[0072] In the embodiments of the present application, by classifying the positive electrode waste powder and then performing targeted repairs based on the conditions of each type of positive electrode waste powder, the repair process of the positive electrode waste powder with high recovery value can recover sufficient products, be simple in means, and be easy to implement, introduce few pollutants, and be highly environmentally friendly, thereby increasing the value of recycling and reusing waste lithium-ion batteries and reducing the environmental pollution caused by waste lithium-ion batteries. Among them, the first positive electrode waste powder is sintered so that the positive electrode waste powder that still has a relatively high battery capacity can be re-formed into commercially viable positive electrode powder, and the repair method is simpler, more environmentally friendly, and has a high recovery rate. The second positive electrode waste powder is wet-processed so that the positive electrode waste powder with a relatively low battery capacity can obtain its valuable metals, thereby increasing its utilization value.

[0073] In some embodiments, the first preset screening condition includes: the waste positive electrode powder and the unused positive electrode powder have at least five XRD characteristic peaks with the same diffraction angle, and / or at least 30% by weight of the particles of the waste positive electrode powder have only cracks or are intact on their surfaces; And / or, the second preset screening condition includes: the positive electrode waste powder and the unused positive electrode powder have at most three XRD characteristic peaks with the same diffraction angle, and / or at least 10% by weight of the particles of the first positive electrode waste powder are surface crushed.

[0074] The first and second preset screening conditions refer to the criteria for classifying waste positive electrode powder. XRD (X-ray diffraction) testing is performed on the waste positive electrode powder and the unused portion of the waste positive electrode powder, respectively, to obtain XRD patterns. The XRD patterns are then compared and analyzed. If the waste positive electrode powder and the unused positive electrode powder share at least five XRD characteristic peaks at the same diffraction angle, the waste positive electrode powder passes the first preset screening condition and is sintered. If the waste positive electrode powder and the unused positive electrode powder share at most three XRD characteristic peaks at the same diffraction angle, the waste positive electrode powder passes the second preset screening condition and is wet-processed. It should be noted that the diffraction peak at a specific diffraction angle in the XRD spectrum of the positive electrode waste powder may not be obvious, or the peak value may be significantly reduced. If there is a corresponding diffraction peak at a specific diffraction angle, it is considered that the positive electrode waste powder and the unused positive electrode powder have at least one XRD characteristic peak at the same diffraction angle.

[0075] ICP (emission spectroscopy) testing is performed on the positive electrode waste powder. If at least 30% of the particles by weight of the tested positive electrode waste powder have only cracks or are intact on the surface, the positive electrode waste powder passes the first preset screening condition and is sintered. If at least 10% of the particles by weight of the first positive electrode waste powder tested have pulverized surfaces, the positive electrode waste powder passes the second preset screening condition and is wet-processed. It should be noted that because lithium iron phosphate positive electrode materials generally have a relatively fine particle size, they are not prone to cracks. Ternary positive electrode materials tend to form balls after use and are prone to surface cracks, which can be repaired through sintering.

[0076] In the embodiments of the present application, by performing XRD and / or ICP testing on the positive electrode waste powder, classifying and screening the positive electrode waste powder, and performing targeted repair on the positive electrode waste powder according to the screening results, the value of recycling and reuse of waste lithium-ion batteries can be increased and the pollution of waste lithium-ion batteries to the environment can be reduced.

[0077] In some embodiments, the step of sintering the first positive electrode waste powder includes: Mixing the first cathode waste powder with a lithium supplement agent to obtain a cathode mixture; The positive electrode mixture is sintered to obtain a first positive electrode repair material.

[0078] The term "lithium replenisher" refers to a lithium-containing material used to replenish the lithium lost in the waste positive electrode powder to increase the capacity of the corresponding battery. In some embodiments, the lithium deficiency of the first waste positive electrode powder is measured based on the lithium content of the target positive electrode powder, and the amount of lithium replenisher to be added is calculated based on the lithium deficiency of the first waste positive electrode powder. In some embodiments, since the first positive electrode repair material is prone to irreversible lithium loss during use, when adding the lithium replenisher, a slightly larger amount than the theoretical addition amount is selected to increase the capacity of the corresponding battery.

[0079] In the embodiments of the present application, a positive electrode mixture obtained by mixing a first positive electrode waste powder with a lithium supplement is sintered to promote the grain development of the first positive electrode waste powder. In some embodiments, cracks on the surface of the particles of the first positive electrode waste powder are repaired to form a new positive electrode repair material that can be commercially used again. The battery capacity of the obtained positive electrode repair material can be restored to more than 95% of the battery capacity of the positive electrode waste powder before use. The obtained first positive electrode repair material can be downgraded and recycled for reuse, for example, from the battery positive electrode material of an electric vehicle to the battery positive electrode material of an electric motorcycle, thereby increasing the utilization value of the positive electrode waste powder. The sintering process is simple and easy to implement, and has an advantage in repair cost. It should be noted that in some cases, the structure of the positive electrode waste powder has already undergone irreversible damage. Even if a lithium supplement is added and sintering is performed, the battery performance of the positive electrode waste powder before use cannot be completely restored.

[0080] In some embodiments, the step of sintering the positive electrode mixture includes: sintering the positive electrode mixture at a first preset temperature for a first preset time; Wherein, the first preset temperature is 800° C.-900° C., and / or the first preset time is 6 hours-12 hours.

[0081] Among them, the first preset temperature refers to the temperature at which the positive electrode mixture is heat treated. Optionally, the first preset temperature is 800℃-900℃. Within this temperature range, the grain size formed is moderate, the grain boundary defects are reduced, and the corresponding battery has a higher capacity. For example, the first preset temperature can be 800℃, 810℃, 820℃, 830℃, 840℃, 850℃, 860℃, 870℃, 880℃, 890℃, 900℃, etc., or a range consisting of any two of the above values, such as 800℃-830℃, 840℃-870℃, 870℃-900℃, etc. The first preset duration refers to the duration of heat treatment at the first preset temperature. Optionally, the first preset duration is 6h-12h. Within this duration range, the grains formed grow fully, have high integrity and fewer defects. For example, the first preset time can be a value such as 6h, 6.5h, 7h, 7.5h, 8h, 8.5h, 9h, 9.5h, 10h, 10.5h, 11h, 11.5h, 12h, or a range consisting of any two of the above values, such as 6h-8h, 8h-10h, 10h-12h, etc. It can be understood that the first preset time refers to the time the sintering system is heated to the first preset temperature and maintained at the preset temperature, and does not include the time it takes to heat up from room temperature to the first preset temperature at a certain heating rate, nor does it include the time it takes to cool down from the first preset temperature to room temperature at a certain cooling rate. In some embodiments, a catalyst can also be added and mixed with the first positive electrode waste powder and the lithium supplement agent. The resulting positive electrode mixture is then sintered to obtain the first positive electrode repair material. The catalyst can be any catalyst known in the art. For example, in some specific embodiments, the catalyst can be Li2SO4. In some embodiments, the positive electrode mixture is sintered in a nitrogen atmosphere for a first preset time. The sintering in the nitrogen atmosphere is to reduce oxidation of the lithium source.

[0082] In the embodiment of the present application, by sintering the positive electrode mixture, the first positive electrode waste mixture can be repaired into a new positive electrode repair material that can be commercially used again, thereby improving the utilization value of the positive electrode waste powder and reducing the production cost of the battery.

[0083] In some embodiments, the lithium supplement includes lithium hydroxide (LiOH), lithium nitrate (LiNO 3, At least one of lithium nitrate and lithium carbonate (Li2CO3, Lithium carbonate).

[0084] In the embodiments of the present application, the lithium deficiency of the first positive electrode waste powder is supplemented by the provided lithium supplement agent to increase the lithium content of the first positive electrode repair material, so that the first positive electrode repair material can be used in the battery again. The battery formed not only has a high energy density and high commercial value, but also has a low production cost. At the same time, it is also beneficial to reduce the pollution of the environment and the waste of resources caused by waste batteries.

[0085] In some embodiments, the step of mixing the first cathode waste powder with the lithium supplement agent includes: ball milling the first cathode waste powder; Among them, the average particle size D of the first cathode waste powder after ball milling is 50 ≦100μm.

[0086] Wherein, ball milling refers to a method of crushing the first cathode waste powder. Optionally, the average particle size D of the first cathode waste powder after ball milling is 50 ≦100μm. Within this range, the obtained ball-milled particles can not only be evenly dispersed, but also significantly reduce the grain size. In the subsequent sintering process, it is also beneficial to reduce the lattice defects of the sintered product and improve the density of the sintered product, thereby improving the battery performance of the sintered product. The ball milling process can be any ball milling process known in the art, and the average particle size D of the first positive electrode waste powder after ball milling is satisfied. 50 The requirement of ≦100μm is sufficient.

[0087] In the embodiment of the present application, by ball milling the first positive electrode waste powder, the grain size of the first positive electrode waste powder can be effectively reduced, and the dispersion uniformity of the first positive electrode waste powder can be improved. In the subsequent sintering process, it is also beneficial to reduce the lattice defects of the sintered product and improve the density of the sintered product, thereby improving the battery performance of the sintered product.

[0088] In some embodiments, the step of wet treating the second cathode waste powder includes: Adding the second cathode waste powder to a leaching agent and a reducing agent at a second preset temperature, and immersing for a second preset time to obtain a second cathode repair material; Wherein, the second preset temperature is 80℃-100℃; and / or, the leaching agent includes at least one of sulfuric acid (H2SO4), acetic acid (CH3COOH), tartaric acid (C4H6O6), and oxalic acid (H2C2O4); and / or, the reducing agent includes at least one of hydrogen peroxide (H2O2), sulfite (M2SO3, M is a +1 valent metal), and thiosulfate (M2S2O3, M is a +1 valent metal); And / or, the second preset duration is 0.5h-5h.

[0089] The second preset temperature refers to the temperature at which the second positive electrode waste powder is wet-processed. Optionally, the second preset temperature is 80°C-100°C. Within this temperature range, the wet-processing rate of the second positive electrode waste powder is improved. For example, the second preset temperature can be 80°C, 81°C, 82°C, 83°C, 84°C, 85°C, 86°C, 87°C, 88°C, 89°C, 90°C, 91°C, 92°C, 93°C, 94°C, 95°C, 96°C, 97°C, 98°C, 99°C, or 100°C, or a range consisting of any two of these values, such as 80°C-85°C, 85°C-90°C, or 90°C-100°C. The second preset duration refers to the duration of wet-processing at the second preset temperature. Optionally, the second preset duration is 0.5h-5h. Within this duration, wet-processing recovery is sufficient, resulting in a high extraction rate of valuable metals. For example, the second preset duration can be a value such as 0.5h, 1h, 1.5h, 2h, 2.5h, 3h, 3.5h, 4h, 4.5h, or 5h, or a range consisting of any two of the above values, such as 0.5h-1.5h, 1.5h-3.5h, or 3.5h-5h. The leaching agent refers to the solvent used in the wet treatment of the second positive electrode waste powder. The reducing agent refers to a material that can reduce metal ions in the system to divalent ions, thereby increasing the leaching rate of metals such as nickel, cobalt, manganese, and lithium.

[0090] In the embodiment of the present application, by wet processing the second positive electrode waste powder, the valuable metals in the second positive electrode waste powder can be fully recovered and reused, thereby improving the utilization value of the second positive electrode waste powder and reducing the production cost of the battery.

[0091] In some embodiments, the step of repairing the waste negative electrode powder includes: Mixing the negative electrode waste powder with a carbon source to obtain a negative electrode mixture; The negative electrode mixture is sintered to obtain negative electrode repair powder.

[0092] The carbon source refers to a material that provides a source of carbon and is used for deep impurity removal of waste negative electrode powder. Specifically, impurities in the waste negative electrode powder that are difficult to remove using macroscopic impurity removal tools, such as metal impurities shed from the negative electrode current collector and / or the SEI (solid electrolyte interface) film that forms on the outside of the waste negative electrode powder particles, are removed through the reducing effect of the carbon source during the sintering process, achieving deep impurity removal of the waste negative electrode powder.

[0093] In the embodiments of the present application, the negative electrode mixture obtained by mixing the negative electrode waste powder and the carbon source is sintered to achieve deep impurity removal of the negative electrode waste powder, and the surface of the negative electrode material after impurity removal is coated with new carbon material, thereby improving the recovery value of the obtained negative electrode repair powder. The sintering process is simple and less polluting, and has more advantages in repair costs.

[0094] In some embodiments, the step of sintering the negative electrode mixture includes: sintering the negative electrode mixture at a third preset temperature for a third preset time; Among them, the third preset temperature is 2200℃-3000℃; And / or, the third preset duration is 20 hours to 70 hours.

[0095] The third preset temperature refers to the temperature at which the negative electrode mixture is sintered. Optionally, the third preset temperature is between 2200°C and 3000°C. Within this temperature range, impurities in the negative electrode waste powder that are difficult to remove using macroscopic impurity removal tools are significantly reduced. For example, the third preset temperature can be 2200°C, 2400°C, 2500°C, 2600°C, 2700°C, 2800°C, 2900°C, or 3000°C, or a range consisting of any two of these values, such as 2400°C to 2600°C or 2700°C to 2900°C. The third preset duration refers to the duration of the sintering process at the third preset temperature. Optionally, the third preset duration is between 22 hours and 70 hours. Within this duration, impurities in the negative electrode waste powder that are difficult to remove using macroscopic impurity removal tools are thoroughly removed. For example, the third preset time can be a value such as 22h, 24h, 36h, 48h, 60h, 70h, or a range consisting of any two of the above values, such as 22h-36h, 48h-60h, etc. It can be understood that the third preset time refers to the time the sintering system is heated to the third preset temperature and maintained at the preset temperature, and does not include the time it takes to heat up from room temperature to the third preset temperature at a certain heating rate, nor does it include the time it takes to cool down from the third preset temperature to room temperature at a certain cooling rate. In some embodiments, a catalyst can also be added and mixed with the negative electrode waste powder and the carbon source. The resulting negative electrode mixture is then sintered to obtain a negative electrode repair powder. The catalyst can be any catalyst known in the art. For example, in an embodiment of the present application, the catalyst can be nickel. In some embodiments, the negative electrode mixture is sintered for a third preset time under an argon atmosphere. Sintering under an argon atmosphere is to reduce oxidation of the carbon source.

[0096] In the embodiments of the present application, by sintering the negative electrode mixture, the waste negative electrode mixture can be repaired into a new negative electrode repair material that can be commercially used again, thereby increasing the utilization value of the waste negative electrode powder and reducing the production cost of the battery.

[0097] In some embodiments, the carbon source includes at least one of artificial graphite and natural graphite; Optionally, the mass ratio of the negative electrode waste powder to the carbon source is 6-8:2-4. Within this mass ratio range, impurities in the negative electrode waste powder that are difficult to remove using macroscopic impurity removal tools can be fully removed. For example, the mass ratio of the negative electrode waste powder to the carbon source can be 6:4, 7:3, 8:2, or a range consisting of any two of these values, such as 6-7:3-4.

[0098] In the embodiments of the present application, the negative electrode waste powder is deeply decontaminated by the provided carbon source, and the surface of the negative electrode material after decontamination is coated with new carbon material, so that the negative electrode repair material can be reused in the battery, thereby improving the reuse value of the negative electrode waste powder, reducing the production cost of the battery, and at the same time reducing the pollution of the environment and the waste of resources caused by waste batteries.

[0099] In some embodiments, the steps of classifying and disassembling waste lithium-ion batteries include: Disassemble the waste lithium-ion batteries to obtain the shell and bare cells; The bare battery cell is disassembled to obtain waste coating film, waste positive electrode sheet, waste negative electrode sheet, residual electrolyte and waste isolation film; At least one of the waste positive electrode sheets and the waste negative electrode sheets is subjected to a powder removal treatment.

[0100] Among them, the shell refers to the component that houses the bare cell, and the shell can contain one or more bare cells. The bare cell is the component in the battery cell where the electrochemical reaction occurs. It is mainly formed by winding or stacking the positive electrode sheet and the negative electrode sheet, and usually a separator is provided between the positive electrode sheet and the negative electrode sheet. In addition, the shell also includes a coating film, which is used to wrap the bare cell inside the shell, thereby realizing the insulation protection between the bare cell and the shell. The bare cell also includes an electrolyte, which is soaked in the positive electrode sheet, the negative electrode sheet and the separator. The waste coating film, waste positive electrode sheet, waste negative electrode sheet, residual electrolyte and waste separator are the retired coating film, positive electrode sheet, negative electrode sheet, electrolyte and separator. The de-powdering treatment of the waste positive electrode sheet is to peel the waste positive electrode powder from the positive electrode current collector so as to facilitate the repair of the waste positive electrode powder. De-powdering of spent negative electrode sheets is performed to separate the spent negative electrode powder from the negative electrode current collector, facilitating its restoration. In some solutions, the disassembled housing is made of metal. The disassembled metal housing, positive electrode current collector, and negative electrode current collector can be processed again based on product quality, with the resulting products being used in other industries or directly commercialized.

[0101] In the embodiments of the present application, waste lithium-ion batteries are recycled and reused to the maximum extent possible by classifying and disassembling the waste lithium-ion batteries and then performing targeted treatment on each of the disassembled parts.

[0102] In some embodiments, the step of removing powder from the waste positive electrode sheets includes: At a fourth preset temperature, washing the waste positive electrode sheets with a cleaning solvent for a fourth preset time, so that the waste positive electrode sheets are separated into a positive electrode current collector and a waste positive electrode powder; Among them, the fourth preset temperature is 20℃-30℃; and / or, the fourth preset duration is 2h-4h; And / or, the cleaning solvent includes deionized water.

[0103] Among them, the fourth preset temperature refers to the temperature when the positive electrode waste electrode is rinsed. Optionally, the fourth preset temperature is 20℃-30℃, and within this temperature range, it has a faster powder removal rate. For example, the fourth preset temperature can be a value such as 20℃, 21℃, 22℃, 23℃, 24℃, 25℃, 26℃, 27℃, 28℃, 29℃, 30℃, or a range consisting of any two of the above values, such as 20℃-24℃, 22℃-25℃, 26℃-29℃, etc. The fourth preset time refers to the time for the powder removal treatment at the fourth preset temperature. Optionally, the fourth preset time is 2h-4h, and within this time range, the powder can be fully removed. For example, the fourth preset time can be a value such as 2h, 2.5h, 3h, 3.5h, 4h, or a range consisting of any two of the above values, such as 2.5h-3.5h, etc. The cleaning solvent refers to a solvent that can separate the positive electrode waste powder from the positive electrode current collector.

[0104] In the embodiment of the present application, by de-powdering the waste positive electrode sheets, the waste positive electrode powder and the positive electrode current collector can be fully separated so that they can be recycled and reused separately, and both can fully realize their reuse value.

[0105] In some embodiments, after the step of de-powdering the waste positive electrode sheets, the step of removing impurities from the waste positive electrode powder is further included, including: At a fifth preset temperature, stirring the waste positive electrode powder with an acidic solution for a fifth preset time; Among them, the fifth preset temperature is 80℃-90℃; and / or, the acidic solution includes at least one of sulfuric acid, hydrochloric acid, and phosphoric acid; and / or, the concentration of the acidic solution is 0.1 mol / L-1.0 mol / L; and / or, the stirring speed is 15 rpm to 50 rpm; And / or, the fifth preset duration is 4 hours to 6 hours.

[0106] The impurity removal in this step refers to the removal of impurities from the waste positive electrode powder. In some embodiments, impurities in the waste positive electrode powder may include invisible aluminum foil, metal wires dropped during battery disassembly, and fluorine elements not removed during the de-powdering process (for example, residual fluorine from the electrolyte and PVDF binder). The fifth preset temperature refers to the temperature at which the waste positive electrode powder is removed. Optionally, the fifth preset temperature is 80°C-90°C, a temperature range that exhibits a rapid impurity removal rate. For example, the fifth preset temperature may be 80°C, 81°C, 82°C, 83°C, 84°C, 85°C, 86°C, 87°C, 88°C, 89°C, or 90°C, or a range consisting of any two of these values, such as 80°C-84°C, 84°C-98°C, or 85°C-90°C. An acidic solution refers to an acidic solution with a pH value less than 7. Optionally, the concentration of the acidic solution is 0.1mol / L-1.0mol / L. Within this concentration range, it has a faster impurity removal rate. For example, the concentration of the acidic solution can be 0.1mol / L, 0.2mol / L, 0.3mol / L, 0.4mol / L, 0.5mol / L, 0.6mol / L, 0.7mol / L, 0.8mol / L, 0.9mol / L, 1.0mol / L and other values, or a range composed of any two of the above values, such as 0.1mol / L-0.4mol / L, 0.4mol / L-0.8mol / L or 0.8mol / L-1.0mol / L, etc. The fifth preset duration refers to the duration of the impurity removal treatment at the fifth preset temperature. Optionally, the fifth preset duration is 4h-6h. Within this duration range, impurities can be fully removed. For example, the fifth preset duration can be 4h, 4.1h, 4.2h, 4.3h, 4.4h, 4.5h, 4.6h, 4.7h, 4.8h, 4.9h, 5h, 5.1h, 5.2h, 5.3h, 5.4h, 5.5h, 5.6h, 5.7h, 5.8h, 5.9h, 6h, etc., or a range consisting of any two of the above values, such as 4h-4.5h, 4.5h-5.5h or 5.5h-6h, etc.

[0107] In the embodiments of the present application, the positive electrode waste powder is subjected to impurity removal treatment to reduce the impact of impurities on the positive electrode waste powder, improve the performance of the positive electrode waste powder obtained after impurity removal, and thereby improve the reuse value of the obtained positive electrode waste powder.

[0108] In some embodiments, the step of removing powder from the waste negative electrode includes: At a sixth preset temperature, flushing the waste negative electrode sheets with water for a sixth preset time, so that the waste negative electrode sheets are separated into a negative electrode current collector and a waste negative electrode powder; Among them, the sixth preset temperature is 20℃-30℃; And / or, the sixth preset duration is 2 hours to 4 hours.

[0109] Among them, the sixth preset temperature refers to the temperature when the negative electrode waste electrode is rinsed. Optionally, the sixth preset temperature is 20℃-30℃, and within this temperature range, it has a faster powder removal rate. For example, the sixth preset temperature can be a value such as 20℃, 21℃, 22℃, 23℃, 24℃, 25℃, 26℃, 27℃, 28℃, 29℃, 30℃, or a range consisting of any two of the above values, such as 20℃-24℃, 22℃-25℃, 26℃-29℃, etc. The sixth preset time refers to the time for the powder removal treatment at the sixth preset temperature. Optionally, the sixth preset time is 2h-4h, and within this time range, powder can be fully removed. For example, the sixth preset time can be a value such as 2h, 2.5h, 3h, 3.5h, 4h, or a range consisting of any two of the above values, such as 2.5h-3.5h, etc.

[0110] In the embodiment of the present application, by de-powdering the waste negative electrode sheets, the waste negative electrode powder and the negative electrode current collector can be fully separated so that they can be recycled and reused separately, and both can fully realize their reuse value.

[0111] In some embodiments, after the step of de-powdering the waste negative electrode sheets, the step of removing impurities from the waste negative electrode powder is further included, including: At a seventh preset temperature, stirring the negative electrode waste powder with an acidic solution for a seventh preset time; Among them, the seventh preset temperature is 80℃-90℃; and / or, the acidic solution includes at least one of sulfuric acid, hydrochloric acid, and phosphoric acid; and / or, the concentration of the acidic solution is 0.1 mol / L-1.0 mol / L; and / or, the stirring speed is 20 rpm to 60 rpm; And / or, the seventh preset duration is 4 hours to 6 hours.

[0112] Among them, the impurity removal in this step refers to a means of removing impurities doped in the negative electrode waste powder. The seventh preset temperature refers to the temperature when the negative electrode waste powder is subjected to impurity removal. Optionally, the seventh preset temperature is 80°C-90°C, and within this temperature range, it has a faster impurity removal rate. For example, the seventh preset temperature can be a value such as 80°C, 81°C, 82°C, 83°C, 84°C, 85°C, 86°C, 87°C, 88°C, 89°C, 90°C, or a range consisting of any two of the above values, such as 80°C-84°C, 84°C-98°C, or 85°C-90°C. Optionally, the concentration of the acidic solution is 0.1mol / L-1.0mol / L, and within this concentration range, it has a faster impurity removal rate. For example, the concentration of the acidic solution can be 0.1mol / L, 0.2mol / L, 0.3mol / L, 0.4mol / L, 0.5mol / L, 0.6mol / L, 0.7mol / L, 0.8mol / L, 0.9mol / L, 1.0mol / L, or a range consisting of any two of the above values, such as 0.1mol / L-0.4mol / L, 0.4mol / L-0.8mol / L, or 0.8mol / L-1.0mol / L. The seventh preset time refers to the time for the impurity removal treatment at the seventh preset temperature. Optionally, the seventh preset time is 4h-6h, within which the impurities can be fully removed. For example, the seventh preset time length can be 4h, 4.1h, 4.2h, 4.3h, 4.4h, 4.5h, 4.6h, 4.7h, 4.8h, 4.9h, 5h, 5.1h, 5.2h, 5.3h, 5.4h, 5.5h, 5.6h, 5.7h, 5.8h, 5.9h, 6h, etc., or a range consisting of any two of the above values, such as 4h-4.5h, 4.5h-5.5h or 5.5h-6h, etc.

[0113] In the embodiments of the present application, the negative electrode waste powder is subjected to impurity removal treatment to reduce the impact of impurities on the negative electrode waste powder, improve the performance of the negative electrode waste powder obtained after impurity removal, and thereby improve the reuse value of the obtained negative electrode waste powder.

[0114] In some embodiments, the step of repairing the residual electrolyte includes: distilling the residual electrolyte to obtain a distillation product; Batch blending of distillation products; Add bulking agent to the mixed batch of distilled products.

[0115] Among them, distillation refers to a means of heating the residual electrolyte to turn it into steam, and then condensing the steam to form a distillation product, thereby removing impurities in the residual electrolyte. The distillation means adopted in the embodiments of the present application can be any distillation means known in the art, as long as the purpose of removing impurities in the residual electrolyte is achieved. Since there is not much residual electrolyte in a single waste bare cell, the embodiments of the present application adopt batch mixing of the distillation products of the residual electrolyte of multiple waste bare cells to reduce the process of repairing the residual electrolyte, improve the repair efficiency and reduce the repair cost. The filler refers to a material containing the missing components of the batch mixed distillation product relative to the unused electrolyte, which is used to repair the batch mixed distillation product to increase the reuse value of the residual electrolyte.

[0116] In the embodiments of the present application, the residual electrolyte is repaired so that the obtained repair product can be commercially used as a battery electrolyte again, thereby increasing the utilization value of the residual electrolyte, reducing the production cost of the battery, and reducing the pollution of the residual electrolyte to the environment.

[0117] In some embodiments, the step of adding a filler to the batch mixed distilled product comprises: measuring the missing component and the amount of the missing component in the batch processed distillation product relative to unused electrolyte; Based on the missing component and the missing amount of the missing component, the composition of the filler is determined and the amount of the filler to be added is calculated.

[0118] The measurement of the missing components and the amount of the missing components in the batch distillation product relative to the unused electrolyte can be performed by any measurement method known in the art. For example, chemical analysis methods such as titration, colorimetry, atomic absorption spectroscopy, etc. can be used to measure the content of elements, ions, compounds, and other components in the distillation product and the unused electrolyte, respectively. The missing components and the amount of the missing components can be determined based on the difference between the two. For example, mass spectrometry (MS) can be used to analyze the compounds in the distillation product and the unused electrolyte, and determine their relative contents. The missing components and the amount of the missing components can be determined based on the difference between the two.

[0119] In the embodiments of the present application, appropriate fillers are added based on the measurement of the missing components and the missing amounts of the distilled product to supplement the missing components in the distilled product, thereby optimizing the performance of the repaired product to meet the expected requirements.

[0120] In some embodiments, the step of disassembling the waste lithium-ion batteries includes: Discharge the used lithium-ion batteries; Optionally, discharge the used lithium-ion battery to below 1V.

[0121] Before disassembling the used lithium-ion batteries, they must be discharged to prevent fires and explosions caused by short circuits. Optionally, the used lithium-ion batteries can be discharged to below 1V to further enhance their safety.

[0122] In the embodiments of the present application, by discharging the waste lithium-ion batteries before disassembling them, the safety performance of the waste lithium-ion batteries is improved and the occurrence of accidents is reduced.

[0123] The beneficial effects of the present application are further illustrated below with reference to the examples.

[0124] In order to make the technical problems, technical solutions and beneficial effects solved by the embodiments of the present application clearer, the following will be further described in detail with reference to the embodiments and drawings. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is in no way intended to limit the present application and its applications. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0125] Example 1 A method for recycling waste lithium-ion batteries, comprising: (1) Discharge the waste lithium-ion battery to 1V, and then disassemble the discharged waste lithium-ion battery to obtain the shell and bare battery cell; (2) Deeply disassembling the bare battery cell obtained in step (1) to obtain waste coating film, waste positive electrode sheet, waste negative electrode sheet, residual electrolyte and waste isolation film; (3) Rinse the waste cathode electrode obtained in step (2) with deionized water at a temperature of 25° C. for 2 h to separate the waste lithium iron phosphate (LFP) powder from the cathode current collector; (4) At a temperature of 80° C., the waste lithium iron phosphate LFP powder obtained in step (3) was added to sulfuric acid with a concentration of 0.1 mol / L and stirred at a speed of 30 r / min for 4 h; (5) Drying the product obtained in step (4), and performing XRD tests on the obtained powder and the powder before use, respectively. The powder has five characteristic peaks with the same diffraction angles as the powder before use. The powder is subjected to ICP testing, and 30% of the particles by weight of the powder have only cracks or are intact on their surfaces. (6) The product of step (5) is subjected to ball milling treatment, and the average particle size D of the first positive electrode waste powder after ball milling is50 100μm; (7) The product obtained in step (6) is mixed with lithium hydroxide in a mass ratio of 100:8 to obtain a positive electrode mixture; the positive electrode mixture is sintered at a temperature of 800° C. for 6 hours to obtain a first positive electrode repair material.

[0126] The prepared first positive electrode repair material was mixed with the conductive agent acetylene black and the binder PVDF in a mortar at a mass ratio of 8:1:1 and ground for 20 minutes. Then a few drops of N-methylpyrrolidone (NMP) organic solvent were added and ground until a uniform bubble-free slurry with a certain viscosity was formed. An automatic coating dryer was used to coat the above slurry on a clean copper foil with a thickness of 15μm to obtain a uniform electrode sheet. After drying at 70°C for 3 hours, it was transferred to a vacuum drying oven and dried at 100°C for 48 hours. A manual ring punching machine was then used to punch the dried positive electrode sheet into a circular electrode sheet with a diameter of about 15.8mm as the positive electrode.

[0127] Artificial graphite, conductive agent carbon black, binder carboxymethyl cellulose (CMC) and styrene-butadiene rubber (SBR) and solvent water are evenly mixed in a weight ratio of 93:2:2:3:100 to form a negative electrode slurry; the negative electrode slurry is then evenly coated on both surfaces of the negative electrode current collector copper foil; dried at 110°C and cold pressed to obtain a dry negative electrode sheet. A manual ring punching machine is used to punch the dried negative electrode sheet into a circular electrode sheet with a diameter of about 15.8 mm as the negative electrode.

[0128] A PP porous film was used as the separator, and 1 mol / L LiPF6 dissolved in an organic solvent of ethylene carbonate (EC) and diethyl carbonate (DEC) in a volume ratio of 1:1 was used as the electrolyte.

[0129] Place the negative electrode shell, spring, gasket, negative electrode plate, drip the corresponding electrolyte, separator, drip the corresponding electrolyte, positive electrode plate, positive electrode shell in the vacuum glove box, then place it on a manual packaging machine to seal and assemble to form a button battery.

[0130] Examples 2-16 use a method similar to that of Example 1 to obtain the first positive electrode repair material. The specific target components of Examples 1-16 are detailed in Table 1.

[0131] Table 1 Performance of the recycling method for waste lithium-ion batteries of Examples 1-16

[0132] According to the test results analysis of Examples 1-16, it can be seen that: According to the test results of Examples 1-3, for lithium iron phosphate materials, at the first preset temperature, as the first preset time increases, the repair effect of the battery fluctuates within a small range; According to the test results of Examples 1, 4, and 5, for lithium iron phosphate materials, under the same first preset time, as the first preset temperature increases, the repair effect of the battery decreases within a small range; According to the test results of Examples 1, 6-8, for lithium iron phosphate materials, under the same first preset time and first preset temperature, using different lithium supplements, the battery repair effect fluctuates within a small range; According to the test results of Examples 9-11, it can be seen that for the ternary material, at the first preset temperature, as the first preset time increases, the repair effect of the battery fluctuates within a small range; According to the test results of Examples 9, 12, and 13, for the ternary material, under the same first preset time, as the first preset temperature increases, the repair effect of the battery decreases within a small range; According to the test results of Examples 9 and 14-16, for ternary materials, at the same first preset time and first preset temperature, using different lithium supplements, the battery repair effect fluctuates within a small range.

[0133] In summary, the embodiments of the present application classify the positive electrode waste powder and then perform targeted repairs based on the conditions of each type of positive electrode waste powder, so that the high-value components of waste lithium-ion batteries can be fully reused, thereby achieving rational reuse of resources.

[0134] Example 17 A method for recycling waste lithium-ion batteries, comprising: (1) Discharge the waste lithium-ion battery to 1V, and then disassemble the discharged waste lithium-ion battery to obtain the shell and bare battery cell; (2) Deeply disassembling the bare battery cell obtained in step (1) to obtain waste coating film, waste positive electrode sheet, waste negative electrode sheet, residual electrolyte and waste isolation film; (3) Rinse the waste negative electrode sheet obtained in step (2) with deionized water at a temperature of 25° C. for 2 h to separate the waste negative electrode powder from the negative electrode current collector; (4) The negative electrode waste powder obtained in step (3) was added to sulfuric acid with a concentration of 0.1 mol / L at a temperature of 80°C and stirred at a speed of 30 r / min for 4 h; (5) drying the product obtained in step (4) and mixing it with a carbon source (artificial graphite) in a mass ratio of 100:8 to obtain a negative electrode mixture; (6) Sinter the negative electrode mixture obtained in step (5) at a temperature of 2500° C. for 32 hours to obtain a negative electrode repair powder.

[0135] The lithium iron phosphate material, the conductive agent acetylene black, and the binder PVDF were mixed and ground in a mortar at a mass ratio of 8:1:1 for 20 minutes. Then, a few drops of N-methylpyrrolidone (NMP) organic solvent were added and ground until a uniform, bubble-free slurry with a certain viscosity was formed. An automatic coating and drying machine was used to coat the above slurry on a clean copper foil with a thickness of 15μm to obtain a uniform electrode sheet. After drying at 70°C for 3 hours, it was transferred to a vacuum drying oven and dried at 100°C for 48 hours. The dried positive electrode sheet was then punched into a circular electrode sheet with a diameter of approximately 15.8mm using a manual ring punching machine as the positive electrode.

[0136] The negative electrode repair material prepared in this embodiment, the conductive agent carbon black, the binder carboxymethyl cellulose (CMC) and styrene-butadiene rubber (SBR), and the solvent water are uniformly mixed in a weight ratio of 93:2:2:3:100 to form a negative electrode slurry; the negative electrode slurry is then evenly coated on both surfaces of the negative electrode current collector copper foil; the negative electrode sheet is dried at 110°C and cold-pressed to obtain a dry negative electrode sheet. A manual ring punching machine is used to punch the dried negative electrode sheet into a circular electrode sheet with a diameter of approximately 15.8 mm as the negative electrode.

[0137] A PP porous film was used as the separator, and 1 mol / L LiPF6 dissolved in an organic solvent of ethylene carbonate (EC) and diethyl carbonate (DEC) in a volume ratio of 1:1 was used as the electrolyte.

[0138] Place the negative electrode shell, spring, gasket, negative electrode plate, drip the corresponding electrolyte, separator, drip the corresponding electrolyte, positive electrode plate, positive electrode shell in the vacuum glove box, then place it on a manual packaging machine to seal and assemble to form a button battery.

[0139] Examples 18-27 use a method similar to Example 17 to obtain negative electrode repair materials. The specific target components of Examples 17-27 are detailed in Table 2.

[0140] Table 2 Performance of the recycling method for waste lithium-ion batteries of Examples 17-27

[0141] According to the test results of Examples 17-27, it can be seen that: According to the test results of Examples 17-19, for lithium iron phosphate materials, as the third preset temperature increases and the third preset time increases, the repair effect of the battery fluctuates within a small range; According to the test results of Examples 18 and 20, for lithium iron phosphate materials, at the same third preset time and third preset temperature, using different carbon sources, the repair effect of the battery fluctuates within a small range; According to the test results of Examples 18, 21-22, for lithium iron phosphate materials, at the same third preset time and third preset temperature, as the mass ratio of the negative electrode waste powder to the carbon source increases, the battery repair effect first increases and then decreases. According to the test results of Examples 23-25, for the ternary material, as the third preset temperature increases and the third preset time increases, the repair effect of the battery fluctuates within a small range; According to the test results of Examples 24, 26 and 27, for the ternary material, at the same third preset time and third preset temperature, as the mass ratio of the negative electrode waste powder to the carbon source increases, the repair effect of the battery increases in a small range.

[0142] In summary, the embodiments of the present application classify the negative electrode waste powder and then perform targeted repairs based on the conditions of each type of negative electrode waste powder, so that the high-value components of waste lithium-ion batteries can be fully reused, thereby achieving rational reuse of resources.

[0143] Example 28: A method for recycling waste lithium-ion batteries, comprising: (1) Discharge the waste lithium-ion battery to 1V, and then disassemble the discharged waste lithium-ion battery to obtain the shell and bare battery cell; (2) Deeply disassembling the bare battery cell obtained in step (1) to obtain waste coating film, waste positive electrode sheet, waste negative electrode sheet, residual electrolyte and waste isolation film; (3) distilling the residual electrolyte to obtain a distillation product; and mixing the distillation product in batches; (4) measuring the missing components and the missing amount of the missing components in the batch distillation product relative to the unused electrolyte; determining the composition of the filler and calculating the amount of the filler to be added based on the missing components and the missing amount of the missing components; (5) Adding filler to the mixed batch of distilled products.

[0144] The positive electrode sheet obtained in Example 17 was used as the positive electrode; the negative electrode sheet obtained in Example 1 was used as the negative electrode.

[0145] A PP porous film was used as the separator, and the repair electrolyte obtained in this example was used as the electrolyte.

[0146] Place the negative electrode shell, spring, gasket, negative electrode plate, drip the corresponding electrolyte, separator, drip the corresponding electrolyte, positive electrode plate, positive electrode shell in the vacuum glove box, then place it on a manual packaging machine to seal and assemble to form a button battery.

[0147] The capacity of the button battery assembled in this embodiment is 151 mAH / g, and the battery capacity can reach 95.15% of the original capacity.

[0148] According to the test results of Example 28, the embodiments of the present application repair the residual electrolyte so that the obtained repair product can be commercially used as a battery electrolyte again, which increases the utilization value of the residual electrolyte and reduces the production cost of the battery.

[0149] In the several embodiments provided in this application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are merely schematic. For example, the division of units is only a logical function division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be an indirect coupling or communication connection through some interface, device or unit, which can be electrical, mechanical or other forms.

[0150] In addition, the functional units in the various embodiments of the present application may be integrated into a single processing unit, or each unit may exist physically separately, or two or more units may be integrated into a single unit. The aforementioned integrated units may be implemented in the form of hardware or software functional units.

[0151] The above description is only an implementation method of the present application and does not limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the description and drawings of this application, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A method for recycling waste lithium-ion batteries, characterized in that: include: Classifying and disassembling waste lithium-ion batteries to obtain at least one of positive electrode waste powder and negative electrode waste powder; Wherein, at least one of the obtained positive electrode waste powder and the obtained negative electrode waste powder is repaired.

2. The method for recycling waste lithium-ion batteries according to claim 1, characterized in that: The steps of repairing the waste positive electrode powder include: According to the first preset screening condition, a first positive electrode waste powder is screened out from the positive electrode waste powder, and the first positive electrode waste powder is sintered; And / or, according to the second preset screening condition, second waste positive electrode powder is screened out from the waste positive electrode powder, and the second waste positive electrode powder is subjected to a wet process.

3. The method for recycling waste lithium-ion batteries according to claim 2, characterized in that: The first preset screening condition includes: the positive electrode waste powder and the unused positive electrode powder have at least five XRD characteristic peaks with the same diffraction angle, and / or at least 30% by weight of the particles of the positive electrode waste powder have only cracks or are intact on their surfaces; And / or, the second preset screening condition includes: the positive electrode waste powder and the unused positive electrode powder have at most three XRD characteristic peaks with the same diffraction angle, and / or the first positive electrode waste powder has at least 10% by weight of particles that are surface crushed.

4. The method for recycling waste lithium-ion batteries according to claim 2, characterized in that: The step of sintering the first positive electrode waste powder comprises: Mixing the first positive electrode waste powder with a lithium supplement to obtain a positive electrode mixture; The positive electrode mixture is sintered to obtain a first positive electrode repair material.

5. The method for recycling waste lithium-ion batteries according to claim 4, characterized in that: The step of sintering the positive electrode mixture comprises: Sintering the positive electrode mixture at a first preset temperature for a first preset time; Wherein, the first preset temperature is 800°C-900°C, and / or the first preset time is 6h-12h.

6. The method for recycling waste lithium-ion batteries according to claim 4, characterized in that: The lithium supplement includes at least one of lithium hydroxide, lithium nitrate and lithium carbonate.

7. The method for recycling waste lithium-ion batteries according to claim 4, characterized in that: The step of mixing the first cathode waste powder with the lithium supplement agent comprises: ball milling the first cathode waste powder; The average particle size D of the first cathode waste powder after ball milling is 50 ≦100μm.

8. The method for recycling waste lithium-ion batteries according to claim 2, characterized in that: The step of wet processing the second positive electrode waste powder comprises: At a second preset temperature, adding the second positive electrode waste powder into a leaching agent and a reducing agent, and immersing for a second preset time to obtain a second positive electrode repair material; Wherein, the second preset temperature is 80°C-100°C; and / or, the leaching agent comprises at least one of sulfuric acid, acetic acid, tartaric acid and oxalic acid; and / or, the reducing agent comprises at least one of hydrogen peroxide, sulfite, and thiosulfate; And / or, the second preset duration is 0.5h-5h.

9. The method for recycling waste lithium-ion batteries according to claim 1, characterized in that: The step of repairing the waste negative electrode powder comprises: Mixing the negative electrode waste powder with a carbon source to obtain a negative electrode mixture; The negative electrode mixture is sintered to obtain negative electrode repair powder.

10. The method for recycling waste lithium-ion batteries according to claim 9, characterized in that: The step of sintering the negative electrode mixture comprises: sintering the negative electrode mixture at a third preset temperature for a third preset time; Wherein, the third preset temperature is 2200°C-3000°C; And / or, the third preset duration is 20h-70h.

11. The method for recycling waste lithium-ion batteries according to claim 9, characterized in that: The carbon source includes at least one of artificial graphite and natural graphite; Optionally, the mass ratio of the negative electrode waste powder to the carbon source is 6-8:2-4.

12. The method for recycling waste lithium-ion batteries according to claim 1, characterized in that: The steps of classifying and disassembling the waste lithium-ion batteries include: Disassemble the waste lithium-ion batteries to obtain the shell and the bare battery cells; Disassembling the bare battery cell to obtain waste coating film, waste positive electrode sheet, waste negative electrode sheet, residual electrolyte and waste isolation film; At least one of the waste positive electrode sheet and the waste negative electrode sheet is subjected to a powder removal treatment.

13. The method for recycling waste lithium-ion batteries according to claim 12, characterized in that: The step of removing powder from the waste positive electrode sheet comprises: At a fourth preset temperature, the waste positive electrode sheet is rinsed with a cleaning solvent for a fourth preset time, and the waste positive electrode sheet is separated into a positive electrode current collector and a waste positive electrode powder; Wherein, the fourth preset temperature is 20°C-30°C; And / or, the fourth preset duration is 2h-4h; And / or, the cleaning solvent includes deionized water.

14. The method for recycling waste lithium-ion batteries according to claim 13, characterized in that: After the step of removing powder from the waste positive electrode sheet, the step of removing impurities from the waste positive electrode powder material also includes: At a fifth preset temperature, stirring the positive electrode waste powder with an acidic solution for a fifth preset time; Wherein, the fifth preset temperature is 80°C-90°C; And / or, the acidic solution includes at least one of sulfuric acid, hydrochloric acid, and phosphoric acid; And / or, the concentration of the acidic solution is 0.1 mol / L-1.0 mol / L; And / or, the stirring speed is 15r / min-50r / min; And / or, the fifth preset duration is 4h-6h.

15. The method for recycling waste lithium-ion batteries according to claim 12, characterized in that: The step of removing powder from the waste negative electrode sheet comprises: At a sixth preset temperature, the waste negative electrode sheet is rinsed with water for a sixth preset time, and the waste negative electrode sheet is separated into a negative electrode current collector and a waste negative electrode powder; Wherein, the sixth preset temperature is 20°C-30°C; And / or, the sixth preset duration is 2h-4h.

16. The method for recycling waste lithium-ion batteries according to claim 15, characterized in that: After the step of removing powder from the waste negative electrode sheet, the step of removing impurities from the waste negative electrode powder material also includes: At a seventh preset temperature, stirring the negative electrode waste powder with an acidic solution for a seventh preset time; Wherein, the seventh preset temperature is 80°C-90°C; And / or, the acidic solution includes at least one of sulfuric acid, hydrochloric acid, and phosphoric acid; And / or, the concentration of the acidic solution is 0.1 mol / L-1.0 mol / L; And / or, the stirring speed is 20r / min-60r / min; And / or, the seventh preset duration is 4h-6h.

17. The method for recycling waste lithium-ion batteries according to claim 13, characterized in that: The step of repairing the residual electrolyte comprises: distilling the residual electrolyte to obtain a distillation product; batch mixing the distillation products; Add filler to the mixed batch of distilled product.

18. The method for recycling waste lithium-ion batteries according to claim 17, characterized in that: The step of adding a filler to the batch mixed distillation product includes: measuring the missing component and the missing amount of the missing component in the batch processed distillation product relative to the unused electrolyte; Based on the missing component and the missing amount of the missing component, the component of the filler is determined and the amount of the filler to be added is calculated.

19. The method for recycling waste lithium-ion batteries according to claim 1, characterized in that: The steps for dismantling used lithium-ion batteries previously included: Discharge the used lithium-ion batteries; Optionally, discharge the used lithium-ion battery to below 1V.

20. A battery, characterized in that: The battery comprises a recycled product of the method for recycling waste lithium-ion batteries according to any one of claims 1 to 19.

21. An electrical device, characterized in that: The electrical device comprises the battery according to claim 20, and the battery is used to provide electrical energy.

Images