Method for recovering materials and valuable metals from waste batteries

Abstract

In this invention, the recovered material from waste batteries contains, based on 100% by weight of the recovered material, 20-35% by weight of valuable metal recovery alloy, 25-50% by weight of lithium compound, and the remainder being graphite-based material.

Description

Technical Field

[0001] The present invention relates to waste batteries, a method for treating waste batteries, a method for recovering valuable metals, lithium oxide, graphite, and copper from waste batteries, and a method for recovering valuable metals.

Background Art

[0002] As the global demand for electric vehicles becomes active, the problem of treating waste batteries generated from electric vehicles has become a social issue. In the case of lithium secondary batteries, which are the main raw materials of the waste batteries, they contain organic solvents, explosive substances, and heavy metal substances such as Ni, Co, Mn, and Fe. In the case of Ni, Co, Mn, and Li, the rare value as valuable metals is large, and the recovery and recycling processes after lithium secondary batteries are discarded have emerged as an important research field.

[0003] Specifically, lithium secondary batteries mainly consist of copper and aluminum used as current collectors, Li, Ni, Co, Mn-containing oxides constituting the positive electrode material, and graphite used as the negative electrode material. It includes a separator for separating the positive electrode material and the negative electrode material and an electrolyte injected into the separator. The solvents used as solvents (Solvent) and salts (Salt) constituting the electrolyte mainly use a mixture of carbonate organic substances such as ethylene carbonate and propylene carbonate, and for example, LiPF6 is used.

[0004] Thus, lithium secondary batteries are composed of heavy metal substances such as Ni-Co-Mn-Fe and carbon and other electrolyte substances, and among them, Ni, Co, Mn, and Li are valuable as valuable metals.

[0005] Recycling for battery raw materials generally involves dismantling, discharging, crushing, heat treatment, recovery, and wet processing of batteries to recover valuable metals. In the case of discharge, saltwater discharge is performed, and substances such as Na, K, Mg, Ca, and Cl that enter at this time are included as impurities in the recovered raw materials.

[0006] After heat treatment, the recovered material produces different products depending on the heat treatment temperature. When heat-treated at temperatures below 600°C, it is called Black Powder, which is a powder mixture of Ni-Co-Mn-Li oxide and carbon (the negative electrode material). Al and Cu are present in very small amounts because they are removed beforehand.

[0007] When the aforementioned black powder is heat-treated at a high temperature of 1,000°C or higher, the metal oxides are reduced and alloyed by the carbon in the negative electrode material, resulting in a black alloy containing such alloy components, carbon, and other substances. Currently, research is needed to recover valuable metals, lithium oxide, and substances such as graphite from the black alloy by material, and to increase the recovery rate of valuable metals. [Overview of the project] [Problems that the invention aims to solve]

[0008] According to one embodiment of the present invention, the recovered material obtained from waste batteries is a recovered material that efficiently recovers valuable metals, lithium oxide, and substances such as graphite from a black alloy obtained from black powder, with a high recovery rate for valuable metals and graphite, and facilitates battery recycling in subsequent processes.

[0009] Another embodiment of the present invention provides a method for recovering valuable metals that increases the recovery rate of valuable metals from black alloy obtained from black powder, and facilitates battery recycling in subsequent processes. [Means for solving the problem]

[0010] In one embodiment of the present invention, the recovered material from a waste battery is a substance recovered from a waste battery, and based on 100% by weight of the recovered material, it may contain 20-35% by weight of a valuable metal recovery alloy, 25-50% by weight of a lithium compound, and the remainder being a graphite-based substance. In one embodiment, the valuable metal recovery alloy may contain Ni, Co, Mn, and impurities.

[0011] In one embodiment, the valuable metal recovery alloy may contain, based on 100% by weight of the entire valuable metal recovery alloy, the total amount of Ni, Co, and Mn may be 90% by weight or more, with the remainder being impurities. In one embodiment, based on 100% by weight of the entire valuable metal recovery alloy, copper (Cu) may be included in an amount of 1 to 7% by weight.

[0012] In one embodiment, the valuable metal recovery alloy may contain, based on 100% by weight of the entire valuable metal recovery alloy, nickel (Ni): 50-60% by weight, cobalt (Co): 18-28% by weight, manganese (Mn): 10-20% by weight, and the remainder being impurities. In another embodiment, the lithium compound may contain, based on 100% by weight of the lithium compound, lithium (Li): 10-20% by weight, aluminum (Al): 20-30% by weight, and the remainder being impurities.

[0013] In one embodiment, the lithium compound may include lithium oxide. In one embodiment, the lithium oxide may include lithium aluminum oxide. In one embodiment, the graphite-based material may contain carbon (C): 80-90% by weight, with the remainder being impurities.

[0014] In one embodiment, the graphite-based material may contain copper (Cu): 13 to 25% by weight. In one embodiment, the valuable metal recovery alloy, the lithium compound, and the graphite-based material may each be in powder form.

[0015] In one embodiment, at least a portion of the lithium compound may include a composition disposed in at least a portion of the surface area of ​​the valuable metal recovery alloy. In one embodiment, the composition may have a core-shell structure.

[0016] Another embodiment of the present invention relates to a method for recovering valuable metals from a product obtained by reducing crushed material recovered from waste batteries at a high temperature, and includes the steps of magnetically separating the heat-treated product into a first magnetic material and a first non-magnetic material, and pulverizing the first magnetic material, wherein the pulverizing step can be performed within a shear force range of 1 to 5 m / sec based on tip speed.

[0017] In one embodiment, the grinding step can be carried out for 30 to 60 minutes.

[0018] In one embodiment, at least a portion of the product obtained by reducing the crushed material recovered from the waste battery at a high temperature may include a valuable metal recovery composition comprising a core portion containing a valuable metal recovery alloy and a shell portion disposed on the core portion and containing a lithium compound. [Effects of the Invention]

[0019] In one embodiment of the present invention, the recovered material from a waste battery contains a valuable metal recovery alloy, a lithium compound, and a graphite-based substance. This allows for the efficient recovery of valuable metals, lithium oxide, and graphite from the black alloy obtained from black powder, thereby increasing the recovery rate of valuable metals and graphite, and enabling the acquisition of recovered material that can be recycled as positive electrode material and negative electrode material in subsequent processes. [Brief explanation of the drawing]

[0020] [Figure 1a] This is a photograph of a valuable metal recovery alloy, lithium compound, and graphite-based material recovered from a waste battery according to one embodiment of the present invention.

[0021] [Figure 1b] A photograph of a valuable metal recovery alloy, a lithium compound, and a graphite-based material of a recovered material recovered from a waste battery according to an embodiment of the present invention.

[0022] [Figure 1c] A photograph of a valuable metal recovery alloy, a lithium compound, and a graphite-based material of a recovered material recovered from a waste battery according to an embodiment of the present invention.

[0023] [Figure 2] A flowchart of a battery processing method according to an embodiment of the present invention.

[0024] [Figure 3a] XRD analysis results of a composition for valuable metal recovery formed after heat treatment according to an embodiment of the present invention.

[0025] [Figure 3b] XRD analysis results of a composition for valuable metal recovery formed after heat treatment according to an embodiment of the present invention.

[0026] [Figure 4] SEM photograph of a composition for valuable metal recovery.

BEST MODE FOR CARRYING OUT THE INVENTION

[0027] The terms first, second, third, etc. are used to describe various parts, components, regions, layers and / or sections but are not limited thereto. These terms are used to distinguish one part, component, region, layer or section from another part, component, region, layer or section. Therefore, the first part, component, region, layer or section described below may be referred to as the second part, component, region, layer or section within a scope not exceeding the scope of the present invention.

[0028] The technical terms used herein are for the sole purpose of referring to specific embodiments and are not intended to limit the invention. The singular form used herein also includes the plural form unless the text explicitly indicates the opposite. The meaning of "includes" as used in this specification is to embody specific characteristics, regions, integers, steps, operations, elements, and / or components, and does not exclude the presence or addition of other characteristics, regions, integers, steps, operations, elements, and / or components.

[0029] When we refer to one part as being "on top of" or "on" another part, it may be directly on top of the other part, or another part may be in between. In contrast, when we refer to one part as being "directly on top of" another part, there is no other part in between.

[0030] Furthermore, unless otherwise specified, percentages in this specification refer to percentages by weight.

[0031] Unless otherwise defined, all terms used herein, including technical and scientific terms, have the same meaning as those generally understood by a person of ordinary skill in the art to which this invention pertains. Terms defined in commonly used dictionaries are additionally interpreted as having the meaning consistent with the relevant technical literature and the present disclosure, and are not interpreted in their ideal or highly formal sense unless otherwise defined.

[0032] The following describes embodiments of the present invention in detail. However, these are presented as examples only and do not limit the present invention; rather, the present invention is defined solely by the scope of the claims described below.

[0033] Figures 1a to 1c are photographs of valuable metal recovery alloys, lithium compounds, and graphite-based materials recovered from waste batteries according to one embodiment of the present invention.

[0034] Referring to Figures 1a to 1c, in one embodiment of the present invention, the recovered material from a waste battery contains, based on 100% by weight of the recovered material, 20 to 35% by weight of a valuable metal recovery alloy, 25 to 50% by weight of a lithium compound, and the remainder being a graphite-based substance. The recovered material from a waste battery may also be the recovered material obtained by the battery processing method described later in Figure 2. Specifically, the recovered material may be a valuable metal recovery alloy containing valuable metals, a lithium compound containing lithium, and the remainder being a graphite-based substance.

[0035] In one embodiment, the recovered material may contain 20-35% by weight of a valuable metal recovery alloy, 25-50% by weight of a lithium compound, and the remainder being a graphite-based substance, based on 100% by weight of the recovered material. From the battery processing method described later, a valuable metal recovery alloy containing valuable metals, a lithium compound containing lithium, and a graphite-based substance containing carbon are recovered in powder form.

[0036] In one embodiment, the valuable metal recovery alloy may be 20 to 35% by weight, based on 100% by weight of the recovered material. Specifically, the valuable metal recovery alloy may be 25 to 30% by weight. The valuable metal recovery alloy may be a substance containing valuable metals such as Ni, Co, and Mn.

[0037] When the weight percentage of valuable metals recovered within the recovered material meets the aforementioned range, it has the advantage of increasing the recovery rate of valuable metals such as Ni, Co, and Mn. If it exceeds the upper limit of the aforementioned range, the recovery rate of valuable metals can be increased, but it presents an economic problem. If it falls below the lower limit of the aforementioned range, there is a problem of a low recovery rate of valuable metals.

[0038] In one embodiment, the valuable metal recovery alloy may contain, based on 100% by weight of the entire valuable metal recovery alloy, the total amount of Ni, Co, and Mn may be 90% by weight or more, with the remainder being impurities. Specifically, the total amount of Ni, Co, and Mn may be 90-96% by weight, and more specifically, 92-95% by weight.

[0039] If the total amount of Ni, Co, and Mn in the valuable metal recovery alloy meets the aforementioned range, the recovery rate of valuable metals can be increased. If the total amount of Ni, Co, and Mn in the valuable metal recovery alloy falls outside the aforementioned range, there are problems such as lack of economic viability or a low recovery rate of valuable metals.

[0040] In one embodiment, nickel (Ni) may be included in a range of 50 to 60% by weight, based on 100% by weight of the entire valuable metal recovery alloy. Specifically, nickel may be included in a range of 52 to 58% by weight.

[0041] If the nickel content exceeds the upper limit of the aforementioned range, there is a problem of reduced leaching rate due to the formation of nickel carbide (Ni3C). If the nickel content falls below the lower limit of the aforementioned range, there is a problem of reduced Ni recovery rate during leaching and solvent extraction.

[0042] In one embodiment, cobalt (Co) may be included in a range of 18 to 28% by weight, based on 100% by weight of the entire valuable metal recovery alloy. Specifically, cobalt may be included in a range of 20 to 26% by weight.

[0043] If the cobalt content exceeds the upper limit of the aforementioned range, there is a problem in that the leaching rate due to cobalt carbide formation decreases. If the cobalt content falls below the lower limit of the aforementioned range, there is a problem in that the Co recovery rate decreases during leaching and solvent extraction.

[0044] In one embodiment, manganese (Mn) may be included in a range of 10 to 20% by weight, based on 100% by weight of the entire valuable metal recovery alloy. Specifically, cobalt may be included in a range of 12 to 18% by weight.

[0045] If the manganese content exceeds the upper limit of the aforementioned range, there is a problem in that the leaching rate due to manganese carbide formation decreases. If the manganese content falls below the lower limit of the aforementioned range, there is a problem in that the Mn recovery rate decreases during leaching and solvent extraction.

[0046] In one embodiment, lithium (Li) may be included in a range of 0.01 to 5% by weight, based on 100% by weight of the entire valuable metal recovery alloy. Specifically, the lithium may be included in a range of 0.05 to 0.15% by weight.

[0047] The advantage of the lithium satisfying the aforementioned range is that the Li recovery rate during the Li smelting process can be maximized. If the lithium exceeds the upper limit of the range, there is a problem of reduced Ni and Co recovery rates, and if it falls below the lower limit of the range, there is a problem of reduced Li recovery rates during the Li smelting process and increased process costs.

[0048] In one embodiment, the valuable metal recovery alloy may contain copper (Cu) in an amount ranging from 1.0 to 7% by weight. Specifically, the amount of copper may be in an amount ranging from 3 to 5% by weight.

[0049] If the copper content exceeds the upper limit of the range, there is a problem of increased process costs due to the increased amount of CuSO4 precipitated during leaching and solvent extraction. If the copper content falls below the lower limit of the range, it becomes difficult to produce low-melting-point Ni-Co-Mn, leading to a problem of increased unreacted material. In one embodiment, the copper can combine with nickel (Ni), one of the valuable metals, to form an alloy.

[0050] In one embodiment, the valuable metal recovery alloy may contain carbon (C) in the range of 0.1 to 10% by weight. By satisfying this range of carbon, the actual yield can be increased and the processing time in the wet process can be shortened. Specifically, the carbon may be contained in the range of 1 to 7% by weight.

[0051] If the value exceeds the upper limit of the aforementioned range, alloying may not occur properly if the negative electrode material remains in an unreacted state, resulting in the problem of valuable metal oxides remaining in the positive electrode material. If the value falls below the lower limit of the aforementioned range, there is a problem that lithium may be lost due to high temperatures.

[0052] In one embodiment, the valuable metal recovery alloy may contain aluminum (Al) in the range of 0.25 to 30% by weight. If the aluminum content exceeds the upper limit of the range, there is a problem of reduced Ni and Co recovery rates during the leaching and solvent extraction processes. If the aluminum content falls below the lower limit of the range, LiAlO2 formation becomes difficult, resulting in a problem of reduced Li recovery rates.

[0053] In one embodiment, the lithium compound may be present in an amount of 25 to 50% by weight, based on 100% by weight of the recovered material. Specifically, the lithium compound may be present in an amount of 30 to 40% by weight. In one embodiment, the lithium compound may be a compound containing lithium. For example, the lithium compound may contain lithium oxide, and the lithium oxide may contain lithium aluminum oxide.

[0054] By satisfying the aforementioned range of the lithium compound, the recovery rate of lithium, one of the valuable metals, can be increased. If the lithium compound falls below the lower limit of the aforementioned range, it means that a large amount of Li was lost due to NCM alloy or graphite, which leads to a problem of reduced Li recovery rate. Furthermore, when Li is recovered in the subsequent wet smelting process, the Li content of the raw materials used will be lower, leading to an increase in process costs.

[0055] In one embodiment, the lithium compound may consist of 10 to 20% lithium (Li) based on 100% lithium compound by weight. Specifically, the lithium may be 12 to 18% by weight.

[0056] If the lithium content exceeds the upper limit of the aforementioned range, it means that lithium does not react with Al to form lithium compounds in the form of LiAlO2, but rather that the proportion of lithium hydroxide, lithium fluoride, lithium carbonate, etc. is high, which presents a problem as methods such as water leaching and acid leaching must be considered in the subsequent wet smelting process. If the lithium content falls below the lower limit of the aforementioned range, it means that most of the lithium compounds were recovered in the form of LiAlO2, which has low water solubility, and that the lithium compounds with high water solubility dissolved in water during the sorting process, which presents a problem as lithium must be recovered again from the water used in the sorting process.

[0057] In one embodiment, the lithium compound may contain 20-30% by weight of aluminum (Al) based on 100% by weight of the lithium compound. Specifically, it may contain 23-28% by weight. By satisfying the above range for the aluminum content, the lithium compound can be formed by physical or chemical bonding with lithium, thereby increasing the lithium yield.

[0058] If the aluminum content exceeds the upper limit of the range, the excess Al2(SO4)3 generated in the leaching and solvent extraction processes leads to increased costs in the Ni, Co solvent extraction and crystallization processes, as well as a decrease in the recovery rate of Ni and Co. If the aluminum content falls below the lower limit of the range, the insufficient aluminum content results in poor Li-Al-O oxide formation.

[0059] In one embodiment, the lithium compound may have a carbon (C) content in the range of 1 to 7% by weight, based on 100% by weight of the lithium compound. Specifically, the carbon (C) content may be 3 to 5% by weight. Meeting this carbon content range offers advantages in optimizing the wet processing of the valuable metal recovery composition.

[0060] If the carbon content exceeds the upper limit of the range, there is a problem of reduced leaching rate due to the formation of nickel carbide (Ni3C). If the carbon content falls below the lower limit of the range, the content of other impurities such as Si increases, leading to a problem of reduced recovery rates of valuable metals such as Ni and Co in solvent extraction after the leaching process.

[0061] In one embodiment, the graphite-based material can be included in an amount of 25-50% by weight, based on 100% by weight of the recovered material. Specifically, the graphite-based material can be included in an amount of 30-40% by weight. The amount of graphite-based material increases as the high-temperature reduction reaction is carried out in a low-oxygen content range that reduces carbon dioxide generation. By satisfying the aforementioned range for the graphite-based material, the recycling yield of graphite-based material that can be used as a negative electrode material can be increased.

[0062] If the graphite-based material exceeds the upper limit of the aforementioned range, the graphite content becomes excessively high, leading to a problem of reduced recovery rates of valuable metals. If the graphite-based material falls below the lower limit of the aforementioned range, there is a problem of low graphite recovery rates.

[0063] In one embodiment, the graphite-based material has a carbon (C) content of 80-90% by weight, and may contain impurities. The carbon (C) content may also be 83-87% by weight. By satisfying the above range for the carbon content, high-purity graphite containing carbon can be obtained.

[0064] If the carbon content exceeds the upper limit of the aforementioned range, there is a problem that the recovery rate of valuable metals will decrease. If the carbon content falls below the lower limit of the aforementioned range, there is a problem that the recovery rate of graphite will be low.

[0065] In one embodiment, the graphite-based material may contain 13 to 25% by weight of copper (Cu) relative to 100% by weight of the graphite-based material. Specifically, the copper content may be 15 to 20% by weight. If the copper content exceeds the upper limit of the aforementioned range, there is a problem in that the amount of acid used to remove Cu during the process of refining graphite into high-purity graphite increases.

[0066] Figure 2 is a flowchart of a battery processing method according to one embodiment of the present invention.

[0067] Referring to Figure 2, the battery processing method includes the steps of preparing an output by reducing crushed material recovered from a waste battery at a high temperature, magnetically separating the output, and crushing the magnetic output from the magnetically separated output to separate magnetic and non-magnetic materials. The battery processing method of the present invention provides a battery processing method that can increase the recovery rate of valuable metals by efficiently performing magnetic separation from the output obtained by reducing crushed material recovered from a waste battery at a high temperature. Valuable metals in the present invention can mean expensive metallic components contained in a battery, and can mean nickel, cobalt, manganese, aluminum, copper, and lithium.

[0068] The step of preparing an output by reducing crushed material recovered from waste batteries at a high temperature includes the steps of preparing batteries, crushing the batteries into battery crushed material, and subjecting the crushed battery crushed material to high temperature heat treatment.

[0069] In the step of preparing the battery, the battery may be a method for processing various types of batteries, including lithium-ion batteries, and the battery may be, for example, a lithium secondary battery separated from an automobile, or a secondary battery separated from an electronic device such as a mobile phone, camera, or laptop computer, specifically a lithium secondary battery. More specifically, the battery has the advantage of being environmentally friendly by utilizing waste batteries.

[0070] In one embodiment, the battery preparation step may include lithium (Li) and aluminum (Al). The coexistence of lithium and aluminum in the battery ensures that, after battery processing, the resulting product contains lithium and aluminum as a substance that is physically and / or chemically bonded together.

[0071] The step of crushing the battery may mean a step of applying impact or pressure to the battery so that a part of the battery separates from the battery. In one embodiment, the step of crushing the battery may mean a step of pulverizing the battery, a step of cutting the battery, a step of compressing the battery, and a combination thereof. Specifically, the crushing step may include all steps that can destroy the battery and obtain it as small-sized fragments.

[0072] In one embodiment, the step of crushing the battery may include all steps of crushing the prepared battery by compressing it or by applying an external force such as shear force or tensile force to destroy the battery. The step of crushing the battery may be carried out, for example, using a crusher.

[0073] In one embodiment, the step of crushing the battery can be performed at least once. Specifically, the crushing step can be performed at least once, either continuously or discontinuously.

[0074] In one embodiment, the step of crushing the battery can be carried out under conditions of supplying an inert gas, carbon dioxide, nitrogen, water, or a combination thereof, or under a vacuum atmosphere of 100 torr or less. When carried out under the aforementioned conditions, oxygen supply can be suppressed, preventing the electrolyte from reacting with oxygen, thereby preventing explosion, suppressing the vaporization of the electrolyte, and preventing the generation of flammable gases such as ethylene, propylene, or hydrogen.

[0075] The step of high-temperature heat treatment of the crushed battery fragments involves placing the battery fragments into a heating furnace capable of raising the temperature to above the melting point. The battery fragments may contain valuable metals such as Ni, Co, Mn, and Li. The high-temperature heat treatment may involve heat treatment conditions that carry out a high-temperature reduction reaction of the battery without going through a melting step.

[0076] In one embodiment, the step of heat-treating the battery fragments at a high temperature can be carried out in a gas atmosphere of at least one of the following: an inert gas, carbon dioxide, carbon monoxide, hydrocarbon gas, and oxygen. In the case of the inert gas, for example, at least one of argon and nitrogen can also be included. Carrying out the reduction reaction of the fragments in the gas atmosphere has the advantage of increasing the recovery rate of valuable metal elements contained in the battery fragments.

[0077] In one embodiment, the step of high-temperature heat treatment of the Ni, Co, Mn, and Li-containing battery fragments can be carried out in a gas atmosphere containing at least one of an inert gas, carbon dioxide, carbon monoxide, and hydrocarbon gas; and oxygen. In one embodiment, the oxygen concentration can be in the range of 0.1 to 2.0 vol%. Specifically, the oxygen concentration can be in the range of 0.4 to 1.2 vol%.

[0078] If the oxygen concentration exceeds the upper limit of the aforementioned range, the Li2O + C + O2(g) = Li2CO3 reaction is promoted as the oxygen concentration increases, but at the same time, there is a problem of a decrease in LiAlO2 and Li5AlO4. Specifically, if the oxygen concentration exceeds the upper limit of the aforementioned range, carbon dioxide is formed in excess during the reduction reaction process and is gasified and disappeared along with lithium, or Li2CO3(s) is produced in excessive amounts, making recovery by acid leaching difficult. If the oxygen concentration falls below the lower limit of the aforementioned range, there is a problem of a decrease in the lithium recovery rate.

[0079] In one embodiment, the step of high-temperature heat treatment of the battery fragments can be carried out in the range of 600 to 1,500°C. Specifically, the high-temperature heat treatment step can be carried out in the range of 900 to 1,500°C, more specifically in the range of 1,100 to 1,500°C, and even more specifically in the range of 1,300 to 1,500°C. In the high-temperature heat treatment step of the battery fragments, as the temperature rises, Li5AlO2(s) + 2Li2CO3(s) = Li5AlO4 + 2CO2(g) reaction is produced, but the LiF(g) vaporization reaction is promoted, and when carried out in the aforementioned range, the lithium yield can be improved.

[0080] If the upper limit of the aforementioned range is exceeded, there is a problem of lithium loss due to lithium vaporization. Specifically, if the upper limit of the aforementioned range is exceeded, as the LiF(g) vaporization reaction is excessively accelerated, there is a problem that the lithium recovery rate decreases due to lithium loss.

[0081] If the value falls below the lower limit of the aforementioned range, the sintering and reduction of the alloying elements do not proceed smoothly, preventing the formation of a stabilized lithium-containing compound. This poses a problem in that it becomes difficult to recover a stabilized lithium compound during future lithium compound recovery. Specifically, if the value falls below the lower limit of the aforementioned range, MnO among the Li-containing Ni, Co, and Mn oxides in the positive electrode material does not dissociate, and MnAl2O4 is produced by the reaction MnO(s) + 2Al(s) + 3 / 2O2 = MnAl2O4(s). This reduces the lithium concentration in the lithium compound and lowers the lithium recovery rate.

[0082] The step of magnetically separating the high-temperature heat-treated product allows for the magnetic separation of the product into a first magnetic material having magnetism and a first non-magnetic material having non-magnetism. Magnetic separation utilizes a magnetic material to separate particles by contact with the magnetic material, and various types of magnetic separation methods can be applied.

[0083] The first magnetic material is a composition containing valuable metals Ni, Co, and Mn, and specifically may be a composition comprising a core portion and a shell portion disposed on the core portion. The core portion may include a valuable metal recovery alloy. The core portion of the valuable metal recovery composition may be recovered from the cathode material component inside a waste battery.

[0084] The shell portion is positioned on the core portion and may contain a lithium compound. Specifically, when recovering valuable metals from a waste battery, the valuable metals in the waste battery exist in oxide form, and reduction occurs through high-temperature heat treatment by graphite in the negative electrode material. At this time, the copper current collector can melt and exist in a liquid state, playing a role in agglomerating the reduced valuable metals. The copper current collector and the aluminum current collector partially undergo a reduction reaction with the positive electrode material oxide, and the remainder reacts with lithium, leaving behind a compound in the form of an oxide containing lithium. A detailed explanation of this will be given later in Figures 3a, 3b and 4.

[0085] The second non-magnetic material may include at least one of a Li-containing compound that was not bonded to a valuable metal in the magnetic separation step, and a carbon-containing graphite material.

[0086] In one embodiment, the magnetic separation step can be performed in a magnetic force intensity range of 1,000 to 5,000 Gauss. Specifically, the magnetic separation step can be performed in a magnetic force range of 2,000 to 3,000 Gauss.

[0087] Performing the magnetic separation step within the aforementioned magnetic field strength range has the advantage of efficiently separating valuable metals. If the magnetic field strength range exceeds the upper limit of the aforementioned range, even trace amounts of valuable metals are recovered, increasing the recovery rate. However, the grade of the recovered valuable metals decreases, and the amount of impurities such as graphite and copper increases. This leads to a decrease in process efficiency in the next step, the wet smelting process, and an increase in processing costs. If the magnetic field strength range falls below the lower limit of the aforementioned range, the recovery rate of valuable metals decreases, and the loss of Ni, Co, and Mn increases.

[0088] The step of crushing the magnetic products among the magnetically separated products to separate the magnetic material from the non-magnetic material may be a step of crushing the magnetically separated first magnetic material. The first magnetic material means, as described above, a core portion containing a valuable metal alloy and a compound containing lithium disposed on the core portion. The first magnetic material can be separated into a core portion and a shell portion through the crushing process. Specifically, the first magnetic material can be separated into a second magnetic material and a second non-magnetic material through the crushing process described above. The second magnetic material means, for example, an NCM alloy containing Ni, Co, and Mn, and the second non-magnetic material is a compound containing lithium, which may be, for example, lithium aluminate (LiAlO2).

[0089] In one embodiment, the first magnetic material can be separated into the valuable metal recovery alloy and a lithium-containing compound by mechanical or physical external force. In this way, not only can the valuable metal recovery alloy be recovered from the valuable metal recovery composition, but the lithium compound can also be separated at the same time, resulting in a high lithium recovery rate and a reduction in the amount of lithium lost.

[0090] In one embodiment, the grinding step is performed using equipment that utilizes shear force in the form of a vertical attrition mill, and the RPM of the agitator for the vertical attrition mill is within a shear force range of 1 to 5 m / sec based on the tip speed. Specifically, the grinding step can be performed within a shear force range of 2 to 3 m / sec tip speed. As the grinding step is performed within the aforementioned shear force range, the NCM alloy, which is the core of the first magnetic material, is not ground, and only the lithium-containing compound, which is the shell portion placed on the core, can be ground into a fine powder.

[0091] At this time, the Tip Speed ​​can be calculated using the following formula: Tip Speed ​​= Pi × Impeller Diameter × RPM / 100

[0092] In one embodiment, if the shear force exceeds the upper limit of the range described above, after the shell portion of the first magnetic material is separated, the internal magnetic material core portion is also pulverized. Since the core portion is made of a flexible metal, the spherical particles are rolled up to a plate-like shape, and then pulverized again into smaller particles. At this time, there is a problem of reduced recovery rate in the process of separating the magnetic material of the core portion from the lithium compound of the shell portion using particle size. If the shear force falls below the lower limit of the range described above, there is a problem that the lithium compound of the shell portion is not pulverized and is recovered together with the magnetic material of the core portion.

[0093] In one embodiment, the grinding step can be carried out for 20 to 80 minutes. Specifically, the grinding step can be carried out for 30 to 60 minutes. As the grinding step is carried out within the aforementioned range, the recovery rate of valuable metals such as Ni, Co, Mn, and Li can be increased.

[0094] If the grinding step exceeds the upper limit of the range described above, the magnetic material in the core and the magnetic material containing the lithium compound in the shell are excessively ground, resulting in rolling in a flexible, plate-like form. This continuous over-grinding causes the plate-like particles to break again into fine powder particles, resulting in insufficient magnetic force for further magnetic separation. If the grinding step falls below the lower limit of the range described above, the shell portion containing the lithium compound cannot be easily separated from the magnetic material in the core-shell structure.

[0095] In one embodiment, the grinding step may be followed by an additional separation step of any of the following: particle size separation, flotation separation, or magnetic separation. Flotation separation is a method of separating particles by considering the difference in specific gravity of different substances, and may, for example, utilize a specific solvent to separate particles based on the relative specific gravity of particles corresponding to the specific solvent.

[0096] When the core and shell portions of the first magnetic material are separated after the pulverization step, the valuable metal alloy is separated in a state with a large particle size due to the flexible properties of the metal, while the lithium-containing compound can be pulverized into a fine powder form with a small particle size. Specifically, the first magnetic material can be separated into a lithium-containing compound with a particle size smaller than 70-80 μm and a valuable metal alloy with a particle size of 70-80 μm or larger.

[0097] In one embodiment, the core and shell portions separated after the grinding step are subjected to particle size separation based on a particle size of 70-80 μm. The lithium-containing compound, which is the shell portion, has a particle size smaller than the aforementioned particle size standard, while the valuable metal alloy, which is the core portion, has a particle size larger than the aforementioned particle size standard. Thus, the valuable metal alloy and the lithium-containing compound can be easily separated by particle size separation.

[0098] In other embodiments, the core and shell portions separated through the grinding step can be subjected to magnetic separation. By magnetic separation, a valuable metal alloy containing magnetic Co can be easily separated from a compound containing non-magnetic lithium.

[0099] In further embodiments, the core and shell portions separated through the grinding step can be subjected to flotation separation. This flotation separation allows for easy separation of the core portion containing precipitated valuable metals from the floating lithium-containing compounds.

[0100] In one embodiment, the process may include a step of flotation separation of the first non-magnetic material. By including graphite, the first non-magnetic material having non-magnetic properties separated in the first magnetic separation step can be separated.

[0101] In one embodiment, the flotation separation step may be a step of separating suspended matter containing graphite from precipitates containing valuable metals. Specifically, the flotation separation step may be a step of suspending the first nonmagnetic and hydrophobic graphite and precipitating and separating the lithium-containing compound and fine-particle valuable metal alloy.

[0102] In one embodiment, the precipitate can be magnetically separated to recover the substance containing the valuable metal, and the recovered substance can be pulverized together with the magnetic product. A detailed explanation of the pulverization step is the same as described above.

[0103] In one embodiment, the steps may include grinding the magnetic products among the magnetically separated products to separate the magnetic and non-magnetic materials, followed by drying the final product. Through the drying step, the valuable metal alloy, lithium-containing compound, and graphite are dried into powder form.

[0104] In one embodiment, the step of drying the final product can be carried out in the range of 80 to 200°C. Specifically, the step of drying the final product can be carried out in the range of 100 to 150°C.

[0105] If drying is performed at a temperature above the upper limit of the aforementioned temperature range, there is a problem of flammable materials such as graphite burning. If drying is performed at a temperature below the lower limit of the aforementioned temperature range, the moisture in the final product, which is the powder particles, cannot be completely dried, resulting in the discharge of a product with a high moisture content, which leads to a problem of increased acid usage in the subsequent wet smelting process.

[0106] Figures 3a and 3b show the XRD analysis results of a valuable metal recovery composition formed after heat treatment according to one embodiment of the present invention.

[0107] Referring to Figures 3a and 3b, it can be confirmed that the valuable metal recovery composition, when subjected to high-temperature reductive heat treatment, is reduced to form compounds containing lithium, such as lithium oxide, by combining with the Al component in the battery instead of forming an alloy, such as Ni, Co, and Mn. The lithium oxide can be confirmed to be formed, for example, as LiAlO2, Li5AlO4, and Li2CO3. In one embodiment, the valuable metal recovery composition may further contain LiF. The amount of LiF is a result depending on the amount of electrolyte remaining according to the degree of pretreatment.

[0108] In one embodiment, LiAlO2 may include at least one XRD peak from among 20.5–21.5°, 29.0–29.5°, 31.5–32.0°, 32.2–33.0°, 60.5–61.5°, and 70.0–72.0°. Li5AlO4 may include at least one XRD peak from among 19.5–20.2° and 21.6–22.2°.

[0109] The LiAl5O8 composition may contain at least one XRD peak from among 15.0–17.4°, 24.2–26.1°, 31.4–33.1°, 36.2–40.3°, 46.1–47.3°, 61.1–63.4°, and 66.2–68.7°. The LiF composition may contain at least one XRD peak from among 37.5–40.2°, 43.9–46.5°, and 64.5–66.5°.

[0110] Li3PO4 compositions may contain at least one XRD peak from 29.2–40.1° and 52–77.1°. Li2SiO3 compositions may contain at least one XRD peak from 17.7–20.1°, 26.1–29.5°, 32.2–36.2°, and 37.6–39.7°. Li4SiO4 compositions may contain at least one XRD peak from 16.2–18.3°, 21.4–25.2°, 34.2–39.7°, and 59.2–63.4°.

[0111] Li2Si2O5 compositions may contain at least one XRD peak from among 16.2–18.3°, 21.4–25.2°, 34.2–39.7°, and 59.2–63.4°. Li2CO3 compositions may contain at least one XRD peak from among 24.0–26.0°, 27.0–29.0°, 34.0–36.0°, and 37.0–39.0°.

[0112] Figure 4 is an SEM image of a valuable metal recovery composition according to one embodiment of the present invention.

[0113] Referring to Figure 4, the valuable metal recovery composition according to one embodiment of the present invention includes a core portion and a shell portion disposed on the core portion. The core portion may include a valuable metal recovery alloy. The valuable metals of the present invention can mean expensive metal components contained in batteries, and can mean nickel, cobalt, manganese, aluminum, copper, and lithium. The core portion of the valuable metal recovery composition may be recovered from the positive electrode material components in waste batteries.

[0114] The shell portion is positioned on the core portion and may contain a lithium compound. Specifically, when recovering valuable metals from a waste battery, the valuable metals in the waste battery exist in oxide form, and reduction occurs through high-temperature heat treatment by graphite in the negative electrode material. At this time, the copper current collector can melt and exist in a liquid state, playing a role in agglomerating the reduced valuable metals. The copper current collector and the aluminum current collector partially undergo a reduction reaction with the positive electrode material oxide, and the remainder reacts with lithium, leaving behind a compound in the form of an oxide containing lithium.

[0115] In one embodiment, the lithium (Li) content in the lithium compound may be 4 to 35% by weight, specifically 4 to 25% by weight, based on 100% by weight of the total. By satisfying the above range for the Li content in the lithium compound, it is possible to satisfy a composition containing a lithium-containing compound that has a high lithium content and excellent lithium recovery rate. If the Li content exceeds the upper limit of the above range, the Li2O content increases, leading to the generation of a large amount of compound that is difficult to recover due to water solubility issues, and thus reducing the lithium recovery rate. If the Li content falls below the lower limit of the above range, the lithium recovery rate is low, resulting in a lack of utility value.

[0116] In one embodiment, the lithium compound may contain at least one of LiAlO2, Li5AlO4, LiAl5O8, Li2CO3, LiF, Li3PO4, Li2SiO3, Li4SiO4, and Li2Si2O5. In one embodiment, the lithium compound may contain lithium aluminum oxide.

[0117] The lithium compound may be, for example, a lithium oxide. The lithium-aluminum oxide can be realized in oxide form through physical or chemical bonding of the lithium contained in the composition.

[0118] In one embodiment, the lithium compound may include lithium aluminum oxide. Specifically, the lithium aluminum oxide content may be 45.0 to 97.0% by weight based on 100% by weight of the valuable metal recovery composition. Specifically, the content may be 70 to 90% by weight.

[0119] If the lithium aluminum oxide content exceeds the upper limit of the aforementioned range, there is a problem in that highly water-soluble lithium hydroxide, lithium carbonate, lithium fluoride, etc. dissolve in large quantities in water during the sorting process. If the lithium aluminum oxide content falls below the lower limit of the aforementioned range, it means that most of the lithium compounds were recovered in the less water-soluble LiAlO2 form, and the highly water-soluble lithium compounds dissolved in water during the sorting process. This presents a problem in that lithium must be recovered again from the water used in the sorting process.

[0120] In one embodiment, the lithium compound may include lithium and silicon-containing oxides. Specifically, the content of the lithium and silicon-containing oxide may be 2 to 30% by weight based on 100% by weight of the valuable metal recovery composition. More specifically, it may be 10 to 25% by weight. By satisfying the aforementioned ranges for lithium and silicon-containing oxides, it is possible to ensure a stable product under high temperature and an appropriate oxygen concentration atmosphere, thereby increasing the actual yield of lithium during acid leaching.

[0121] If the content of lithium and silicon-containing oxides exceeds the upper limit of the aforementioned range, it means that the reactor was exposed to the maximum temperature for a long time during the high-temperature reduction reaction, which leads to problems such as reduced reactor productivity and increased energy costs. If the content of lithium and silicon-containing oxides falls below the lower limit of the aforementioned range, it means that there was insufficient thermal energy for lithium to react with aluminum, silicon, etc., to produce lithium compounds such as lithium aluminate, or that the reactor temperature was too high, causing lithium to volatilize and be removed, which leads to problems such as a low lithium recovery rate.

[0122] In one embodiment, the valuable metal recovery composition may contain 10% by weight or less of silicon (Si) based on 100% by weight of the valuable metal recovery composition. Specifically, the silicon content is 1.0% by weight or less, and more specifically, 0.5% by weight or less.

[0123] If the silicon (Si) content exceeds the upper limit of the aforementioned range, there is a problem that the process time and cost will increase in the subsequent wet smelting process to remove the silicon to battery grade. If the silicon (Si) content falls below the lower limit of the aforementioned range, there is a problem that the remaining weight % of silicon in the input raw material will disperse into graphite and lithium compounds, and the process time and cost will increase in the process of refining and smelting the graphite and lithium compounds.

[0124] In one embodiment, Li2CO3 is present in an amount of 30% or less based on 100% by weight of the entire composition. More specifically, the amount of Li2CO3 is 15.0% or less, and more specifically, 5% or less. By keeping the Li2CO3 content within the aforementioned range, there is an advantage in preventing the large-scale generation of compounds that are difficult to recover due to water solubility issues.

[0125] In one embodiment, LiF is present in an amount of 30% by weight or less based on 100% by weight of the entire composition. The LiF is present in an amount of 6.5 to 24.0% by weight, more specifically, 6.5 to 15% by weight or less based on 100% by weight of the entire composition. By keeping the LiF content within the above range, there is an advantage in preventing the generation of large quantities of compounds that are difficult to recover due to water solubility issues.

[0126] If the LiF exceeds the upper limit of the aforementioned range, pH adjustment becomes difficult due to the mixing of sulfate and fluoride ions during sulfuric acid leaching, leading to a problem of reduced Li recovery. If the LiF falls below the lower limit of the aforementioned range, the levels of Li2SiO3, Li4SiO4, and Li2Si2O5 become high, making sulfuric acid leaching difficult and potentially delaying the leaching process time.

[0127] In one embodiment, the total content of Li2CO3 and LiF is 50% or less based on 100% by weight of the entire composition. Specifically, the total content is 0.5 to 50%, and more specifically, the content is 0.5 to 30% or less.

[0128] If the total content exceeds the upper limit of the aforementioned range, a large amount of compounds that are difficult to recover due to water solubility issues are generated, making it difficult to recover Li. If the total content falls below the lower limit of the aforementioned range, the levels of Li2SiO3, Li4SiO4, and Li2Si2O5 in the compound become high, making sulfuric acid leaching difficult and delaying the leaching process time.

[0129] By ensuring that the total amount of Li2CO3 and LiF meets the aforementioned range, it is possible to prevent the large-scale generation of compounds that are difficult to recover due to water solubility issues, and to generate a large amount of compounds that are stable due to appropriate adjustment of high temperature and oxygen concentration, and have excellent sulfuric acid leaching rates, thereby improving the efficiency of lithium recovery.

[0130] In one embodiment, Li3PO4 is included in an amount of 10% by weight or less based on 100% by weight of the entire composition. The Li3PO4 is included in an amount of 5% by weight, specifically 3% by weight or less, and more specifically 0.1 to 0.7% by weight, based on 100% by weight of the entire composition. By satisfying the above range of Li3PO4 content, the PO4 during acid leaching is 3- This prevents a decrease in Li recovery rate due to leaching movement in response to pH changes caused by anions and the generation of LiOH during impurity removal. By ensuring that the Li3PO4 content satisfies the aforementioned range, PO3PO4 is released during acid leaching. 3- This prevents a decrease in Li recovery rate due to issues such as leaching in response to pH changes caused by anions and LiOH generation during impurity removal. [Examples]

[0131] The following describes preferred embodiments and comparative examples of the present invention. However, the following embodiments are merely preferred embodiments of the present invention, and the present invention is not limited to these embodiments.

[0132] <Experimental Example 1> 1. Steps to prepare a valuable metal recovery composition. A cell, module, or pack of a used electric vehicle battery is prepared, containing a lithium-ion positive electrode material, a graphite negative electrode material, an aluminum current collector, a separator membrane, an electrolyte, and a copper current collector. The used battery is then crushed using a method that involves freezing it at -30°C or below, or discharging it under saltwater discharge or electrical discharge conditions, and then shredding it using a shredder under atmospheric or inert gas conditions so that the longest horizontal and vertical length of the used battery is 100 mm or less.

[0133] After obtaining the valuable metal recovery composition using the method described above, the crushed battery fragments were heat-treated at 1,300°C under an oxygen partial pressure of 0.5% to perform a reduction process. After the reduction process, a valuable metal recovery composition was produced, consisting of a core portion containing valuable metals and a shell portion containing a lithium-containing compound on the core portion, as described above.

[0134] Table 1 below shows the components and content of the valuable metal recovery composition produced by the method described above.

[0135] The components and their contents in Table 1 below were measured using quantitative analytical methods with equipment such as ICP-OES and C / S analysis equipment.

[0136] [Table 1]

[0137] 2.1 Primary Magnetic Separation Step A composition for recovering valuable metals, which had undergone a high-temperature reduction process, was separated into magnetic and non-magnetic materials using a magnetic separator with a magnetic field strength of 3000 gauss.

[0138] Experimental Example 2_1 in Table 2 below shows the components and content of magnetic and non-magnetic materials separated by a 3000 Gauss magnetic separator.

[0139] [Table 2]

[0140] As shown in Table 2 above, in the case of magnetic material separated by magnetic separation as in Experimental Example 2_1, it was confirmed that it contained valuable metals such as NCM metals, and that the content of Li, Ni, Co, and Mn was high. In the case of particles separated into non-magnetic material by magnetic separation as in Experimental Example 2_2, it was confirmed that Li, Al, and graphite particles were mostly separated, and that the content of C was high.

[0141] 3_1. Flotation sorting step As in Experimental Example 2_2, the non-magnetic materials separated by magnetic separation were subjected to flotation separation using the Denver Sub_A flotation equipment in Experimental Example 3_1, with a mineral solution concentration of 30%, an impeller rotation speed of 500 rpm, kerosene at 0.1 ml / 100 g, and MIBC at 0.1 ml / 100 g.

[0142] As a result of the flotation separation, the lighter graphite powder floated to the top of the equipment, and the graphite was recovered by separating it.

[0143] Table 3 below shows the components and content of the product after undergoing the flotation separation process.

[0144] [Table 3]

[0145] Table 3 shows that the carbon content of the material suspended in the Overflow (O / F) was 92.5%, a significant increase compared to the initial battery shredder's carbon content of 35.07% and the raw material's carbon content of 75.30% after being separated into non-magnetic materials by magnetic separation and fed into the flotation separator. The carbon content of the precipitate remaining in the Underflow (U / F) was 5.75%, indicating that most of the hydrophobic carbon was recovered as suspended matter. Furthermore, the lithium content ratio between the suspended matter and the precipitate shows that most of the lithium did not float but remained as precipitate, allowing for efficient separation of carbon and lithium by flotation. The high aluminum content of the precipitate suggests that most of the lithium remained as precipitate in the form of LiAlO2. Cu also did not float but mostly remained as precipitate, with a content of 18.04%.

[0146] 4. Grinding step and secondary magnetic separation step 2_1. The magnetic material that has undergone the magnetic separation step is then pulverized using an Attrition Mill, which is a vertical stirring mill, at 500 rpm, with an impeller tip speed of 2.8 m / sec, a pulverization time of 60 minutes, and a soil content of 30% by weight. As described above, the magnetic material is a valuable metal recovery composition consisting of a core part containing a valuable metal and a shell part containing a lithium-containing compound placed on the core part, and it was confirmed that the core part and the shell part separate after the pulverization process.

[0147] Table 5 below shows the components and content of the resulting material separated according to particle size from the magnetic material, including the core and shell portions.

[0148] [Table 4]

[0149] As shown in Table 5 above, in order to separate the alloy core containing valuable metals from the lithium compound after the crushing process, a 3000 gauss magnetic separator was used to separate the magnetic and non-magnetic materials. The results confirmed that Experimental Example 4_1, which was the core containing valuable metals, contained excessive amounts of Ni, Co, and Mn. Experimental Example 4_2, which was separated into non-magnetic materials, was the result of crushing the shell containing lithium, and it was confirmed that it had a high lithium content. In the crushing process, the shell, which is in oxide form, is crushed, and the flexible core is continuously crushed inside the crusher, and as it is rolled into a plate shape, the particle size becomes larger than the initial particle size, and the thickness becomes thinner. In contrast, the shell is in oxide form and is highly brittle, so as the crushing time increases, the crushing continues and the particle size decreases.

[0150] 5.2 Secondary Separation Step Experimental Example 4_1, after undergoing the grinding step, can also be separated by particle size separation utilizing the difference in grinding characteristics between the core alloy and the oxide compound in the shell. However, it is more preferable to perform secondary separation through a magnetic separation process with a magnetic force strength of 3000 Gauss, taking advantage of the magnetic properties of the core alloy. In this case, when separation is performed using magnetic separation, the recovery rate of valuable metals from the core can be increased compared to particle size separation. When particle size separation is applied, separation should be performed using a mesh with a mesh size of 75 μm or 45 μm. In this case, coarse particles are recovered in the NCM alloy, and fine particles are recovered in the Li oxide.

[0151] 6. Drying step The magnetic material containing Ni, Co, and Mn, the non-magnetic material containing Li, and the graphite, separated through the aforementioned steps, were dewatered to reduce their moisture content to 30% using a drum-type dewatering machine or a centrifugal dewatering machine. After that, they were dried to a moisture content of 5% or less using hot air at 100-200°C and then recovered.

[0152] Table 5 below shows the components and content of the final product recovered through the steps described above.

[0153] [Table 5]

[0154] As shown in Table 5 above, valuable metal alloys mainly composed of Ni, Co, and Mn can be recovered from magnetic materials separated through magnetic separation, crushing, and magnetic separation steps, as in Experimental Example 4_1. Lithium compounds, mainly composed of lithium, can be recovered from the total amount of non-magnetic materials separated through magnetic separation, crushing, and magnetic separation steps, as in Experimental Example 4_2, and materials precipitated by flotation, as in Experimental Example 3_2. Graphite can be recovered by separating suspended materials by flotation, as in Experimental Example 3_1. Thus, it was confirmed that by going through the battery processing method described above, valuable metal alloys containing valuable metals such as Ni, Co, and Mn can be recovered, and at the same time, lithium compounds with a high lithium content can be separated, thereby increasing the recovery rate of the valuable metals Li, Ni, Co, and Mn. It was also confirmed that the recovery rate of graphite that can be used as a negative electrode material can be increased by separating graphite separately.

[0155] <Experimental Example 2>: Changes in the composition of magnetic and non-magnetic materials in response to changes in magnetic field strength Table 6 below shows the changes in the composition of magnetic and non-magnetic materials in response to changes in magnetic field strength during primary magnetic separation.

[0156] [Table 6]

[0157] Referring to Table 6 above, when examining the changes in the composition of magnetic and non-magnetic materials in response to changes in magnetic force intensity during primary magnetic separation, at weak magnetic force intensities of 500 and 1000 gauss (G), the grade of the NCM cathode material recovered as a magnetic product is high, but the recovery rate (Dist.) is low at 90% or less, resulting in low Li content and recovery rate. However, at 2000 gauss or higher, it can be confirmed that the majority of the NCM cathode material is recovered as a magnetic material.

[0158] <Experimental Example 3>: Secondary magnetic separation after controlling grinding conditions Table 7 below shows the results of separating the magnetic and non-magnetic materials after the magnetic material was crushed following primary magnetic separation and then again using a 3000 Gauss magnetic separator.

[0159] In this study, a vertical agitation ball mill (Attrition Mill) was used as the grinding machine. The grinding conditions were RPM 500 (Tip Speed ​​2.65 m / sec), the size of the grinding container was 1 L, the solid content concentration was 30%, and the grinding time ranged from 0 to 90 minutes. Magnetic and non-magnetic materials were analyzed for each grinding time.

[0160] [Table 7]

[0161] As shown in Table 7, at point 10, which is the initial stage of pulverization, only a portion of the lithium compound in the shell coating the NCM alloy was pulverized, and the recovery rate of the NCM alloy recovered as magnetic material remained at levels of Ni 86%, Co 87%, and Mn 85%. However, when the pulverization time reached 30 to 60 minutes, it could be confirmed that the recovery rate of Ni, Co, and Mn exceeded 90%. Furthermore, when the pulverization time exceeded 60 minutes and then 90 minutes, the lithium compound was mostly pulverized and recovered as non-magnetic material with a high recovery rate of 91%. However, the NCM alloy core, after the shell was completely removed, was rolled into a plate-like shape due to its flexibility, and then continuously over-pulverized, causing the plate-like particles to break again into fine powder particles. This resulted in excessively fine particles, and the influence of magnetic force on individual particles became minimal. As a result, the atomized NCM alloy portion, even if it exhibits magnetism during magnetic separation, was not recovered as a magnetic material, and this was confirmed to have decreased again to below 85%, which is the recovery rate for Ni, Co, and Mn.

[0162] Although preferred embodiments have been described in detail above, the scope of the present invention is not limited thereto. Various modifications and improvements by those skilled in the art, utilizing the basic concepts defined in the following claims, also fall within the scope of the present invention.

Claims

1. It is a substance recovered from a used battery, The recovered material consists of 100% by weight of the recovered material, with 20-35% by weight of valuable metal recovery alloy, 25-50% by weight of lithium compound, and the remainder being graphite-based material, recovered from waste batteries.

2. The valuable metal recovery alloy is a recovered material obtained from a waste battery according to claim 1, comprising Ni, Co, Mn, and impurities.

3. The valuable metal recovery alloy is a recovered material obtained from a waste battery according to claim 2, wherein the total amount of Ni, Co, and Mn is 90% or more by weight, based on 100% by weight of the entire valuable metal recovery alloy, and the remainder is made up of impurities.

4. A recovered material from a waste battery according to claim 3, comprising 1 to 7% by weight of copper (Cu) based on 100% by weight of the entire valuable metal recovery alloy.

5. The valuable metal recovery alloy is a recovered material obtained from a waste battery according to claim 3, comprising 50-60% by weight nickel (Ni), 18-28% by weight cobalt (Co), 10-20% by weight manganese (Mn), and the remainder being impurities, based on 100% by weight of the entire valuable metal recovery alloy.

6. The lithium compound is a recovered material from a waste battery according to claim 1, comprising 100% by weight of lithium compound, with lithium (Li) at 10-20% by weight, aluminum (Al) at 20-30% by weight, and the remainder being impurities.

7. The lithium compound is a recovered material obtained from a waste battery according to claim 1, which contains lithium oxide.

8. The lithium oxide is a recovered material obtained from a waste battery according to claim 7, which contains lithium aluminum oxide.

9. The graphite-based material is a recovered material from a waste battery according to claim 1, comprising 80-90% by weight of carbon (C) and the remainder being impurities.

10. The graphite-based material is a recovered material from a waste battery according to claim 1, comprising copper (Cu): 13 to 25% by weight.

11. The recovered material from a waste battery according to claim 1, wherein the valuable metal recovery alloy, the lithium compound, and the graphite-based substance are each in powder form.

12. The recovered material from a waste battery according to claim 1, wherein at least a portion of the lithium compound is a composition disposed in at least a portion of the surface area of ​​the valuable metal recovery alloy.

13. The composition is a recovered material obtained from a waste battery according to claim 12, having a core-shell structure.

14. A method for recovering valuable metals from a product obtained by reducing crushed material recovered from waste batteries at high temperatures, A step of magnetically separating the heat-treated product into a first magnetic material and a first non-magnetic material; The step includes grinding the first magnetic material, The aforementioned crushing step is performed within a shear force range of 1 to 5 m / sec based on Tip Speed, and is a method for recovering valuable metals.

15. The method for recovering valuable metals according to claim 14, wherein the crushing step is performed for 30 to 60 minutes.

16. At least a portion of the products obtained by reducing the crushed material recovered from the aforementioned waste batteries at high temperatures is, Core portion containing a valuable metal recovery alloy; and A method for recovering valuable metals according to claim 14, comprising a valuable metal recovery composition disposed on the core portion and including a shell portion containing a lithium compound.

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