Method of disposal of waste batteries

Abstract

The present invention relates to a method of disposal of waste batteries. The method of disposal of waste batteries, of the present invention, comprises the steps of: preparing a product acquired by reducing and heat-treating crushed material recovered from waste batteries at a high temperature; magnetically separating the product into a first magnetic substance and a first non-magnetic substance; pulverizing the first magnetic substance so as to separate the first magnetic substance into a second magnetic substance and a second non-magnetic substance; and performing flotation sorting on the first non-magnetic substance.

Description

How to dispose of used batteries

[0001] The present invention relates to waste batteries and a method for processing waste batteries for efficient recovery of materials such as valuable metals, lithium oxide, graphite, and copper.

[0002] As global demand for electric vehicles grows, the disposal of waste batteries generated from these vehicles is emerging as a social issue. Lithium secondary batteries, the primary raw material for these waste batteries, contain organic solvents, explosive materials, and heavy metals such as nickel, cobalt, manganese, and iron. However, nickel, cobalt, manganese, and lithium are valuable metals with high scarcity value. Therefore, the recovery and recycling processes for discarded lithium secondary batteries are emerging as a key research area.

[0003] Specifically, a lithium secondary battery is mainly composed of copper and aluminum used as a current collector, Li, Ni, Co, Mn-containing oxides constituting a positive electrode material, and graphite used as an anode material, and includes a separator separating the positive electrode material and the negative electrode material, and an electrolyte injected into the separator. The solvent used as a solvent and salt constituting the electrolyte is mainly a mixture of carbonate organic substances such as ethylene carbonate and propylene carbonate, and for example, LiPF6 is used.

[0004] In this way, lithium secondary batteries are composed of heavy metal materials such as Ni-Co-Mn-Fe, carbon, and other electrolyte materials, among which Ni, Co, Mn, and Li are valuable as precious metals.

[0005] Recycling for battery raw material recovery typically involves battery disassembly, discharging, crushing, heat treatment, recovery, and wet processes to recover valuable metals. During this process, saltwater discharging is performed, and substances such as sodium, potassium, magnesium, calcium, and chloride (Ca) that enter the recovered raw material are included as impurities.

[0006] After heat treatment, the recovered material forms different products depending on the heat treatment temperature. When heat treated at a temperature below 600 ℃, it is called black powder and is a powder form in which the oxide of Ni-Co-Mn-Li and carbon of the negative electrode material are mixed. Since Al and Cu are removed in advance, they may be included in extremely small amounts.

[0007] When the above black powder is heat-treated at a high temperature of 1,000°C or higher, the metal oxide is reduced and alloyed by the carbon of the negative electrode material, and a black alloy containing the alloy components, carbon, and other substances is obtained. Research is needed to increase the recovery rate of valuable metals by recovering materials such as valuable metals, lithium oxide, and graphite by material from the black alloy.

[0008] According to one embodiment of the present invention, a battery processing method provides a method for efficiently recovering materials such as valuable metals, lithium oxide, and graphite by material from a black alloy obtained from black powder, thereby increasing the recovery rate of valuable metals and graphite.

[0009] According to one embodiment of the present invention, a battery processing method may include the steps of preparing a product obtained by subjecting shredded material recovered from a spent battery to a high-temperature reduction and heat treatment, magnetically separating the product into a first magnetic body and a first non-magnetic body, crushing the first magnetic body to separate it into a second magnetic body and a second non-magnetic body, and flotation and separation of the first non-magnetic body. In one embodiment, the step of preparing a product obtained by subjecting shredded material recovered from a spent battery to a high-temperature reduction and heat treatment may include the steps of preparing a battery, crushing the battery into battery shreds, and heat-treating the crushed battery shreds at a temperature range of 600 to 1,500°C.

[0010] In one embodiment, the heat treatment step may be performed at an oxygen concentration of 0.1 to 2.0 vol%. In one embodiment, the first magnetic body may include a precious metal alloy including a precious metal, and at least some of the precious metal alloy may include a core-shell structure in which a lithium compound is disposed on at least a portion of a surface of the precious metal alloy.

[0011] In one embodiment, the second non-magnetic material may include at least one of a lithium-containing compound and graphite. In one embodiment, the magnetic separation step may be performed at a magnetic strength range of 1,000 to 5,000 Gauss.

[0012] In one embodiment, the step of further separating the first magnetic material based on a particle size of 50 to 70 μm may be further included. In one embodiment, the step of separating the second magnetic material and the second non-magnetic material by crushing the magnetically separated product among the magnetically separated products may be performed at a shear force range of 1 to 5 m / sec.

[0013] In one embodiment, the step of crushing the magnetic product among the magnetically separated products to separate the second magnetic body and the second non-magnetic body may be performed for 20 to 80 minutes. In one embodiment, the step of crushing the magnetic product among the magnetically separated products to separate the magnetic body and the non-magnetic body may be performed by crushing the magnetic product and then performing any one of particle size separation, flotation, and magnetic separation.

[0014] In one embodiment, the particle size separation may be performed based on a particle size of 70 to 80 μm. In one embodiment, the flotation selection step may select a flotation material including graphite and a sediment material including valuable metals.

[0015] In one embodiment, the sediment may be magnetically separated to recover a material containing valuable metals, and the recovered material may be pulverized together with the magnetic product. In one embodiment, after the step of pulverizing the magnetic product among the magnetically separated products to separate magnetic and non-magnetic materials, the step of drying the final product may be included.

[0016] In one embodiment, the step of drying the final product may be performed at a temperature range of 80 to 200° C. In one embodiment, in the step of preparing a product by reducing and heat-treating the recovered scrap from the spent battery at a high temperature, at least a portion of the product may include a composition for recovering valuable metals, the composition including a core portion comprising a valuable metal recovery alloy, and a shell portion disposed on the core portion and comprising a lithium compound.

[0017] According to one embodiment of the present invention, a battery processing method includes a step of magnetically separating and crushing a product subjected to high-temperature reduction heat treatment, thereby efficiently recovering materials such as valuable metals, lithium oxide, and graphite by material from a black alloy obtained from black powder, thereby increasing the recovery rate of valuable metals and graphite.

[0018] FIGS. 1A to 1C are photographs of valuable metal recovery alloys, lithium compounds, and graphite-based materials recovered from spent batteries according to one embodiment of the present invention.

[0019] Figure 2 is a flowchart of a battery processing method according to one embodiment of the present invention.

[0020] Figure 3 is an XRD analysis result of a black alloy formed after heat treatment according to one embodiment of the present invention.

[0021] Figure 4 is an SEM photograph of a composition for recovering valuable metals.

[0022] The terms first, second, and third, etc., are used to describe, but are not limited to, various parts, components, regions, layers, and / or sections. These terms are used only to distinguish one part, component, region, layer, or section from another part, component, region, layer, or section. Accordingly, a first part, component, region, layer, or section described below may be referred to as a second part, component, region, layer, or section without departing from the scope of the present invention.

[0023] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the present invention. As used herein, the singular forms "singular" and "comprising" include plural forms as well, unless the context clearly dictates otherwise. The word "comprising" as used herein specifies a particular feature, region, integer, step, operation, element, and / or component, but does not exclude the presence or addition of other features, regions, integers, steps, operations, elements, and / or components.

[0024] When a part is referred to as being "on" or "over" another part, it can be directly on or over the other part, or there may be other parts intervening. Conversely, when a part is referred to as being "directly on" another part, there are no other parts intervening.

[0025] Additionally, % in this specification means weight % unless otherwise specified.

[0026] Although not defined otherwise, all terms, including technical and scientific terms, used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present invention pertains. Terms defined in commonly used dictionaries are further interpreted to have meanings consistent with the relevant technical literature and the present disclosure, and are not to be construed as ideal or overly formal unless otherwise defined.

[0027] Hereinafter, embodiments of the present invention will be described in detail. However, these are presented as examples and the present invention is not limited thereto, and the present invention is defined solely by the scope of the claims set forth below.

[0028] FIGS. 1A to 1C are photographs of valuable metal recovery alloys, lithium compounds, and graphite-based materials recovered from spent batteries according to one embodiment of the present invention.

[0029] Referring to FIGS. 1A to 1C, according to an embodiment of the present invention, a recovered material from a spent battery includes 20 to 35 wt% of a valuable metal recovery alloy, 25 to 50 wt% of a lithium compound, and the remainder a graphite-based material, based on 100 wt% of the recovered material. The recovered material from the spent battery may be a recovered material recovered by the battery processing method described later in FIG. 2. Specifically, the recovered material may be a valuable metal recovery alloy including a valuable metal, a lithium compound including lithium, and the remainder a graphite-based material.

[0030] In one embodiment, the recovered material may comprise 20 to 35 wt% of a valuable metal recovery alloy, 25 to 50 wt% of a lithium compound, and the remainder of a graphite-based material, based on 100 wt% of the recovered material. From the battery processing method described below, a valuable metal recovery alloy including a valuable metal, a lithium compound including lithium, and a graphite-based material including carbon can be recovered in powder form.

[0031] In one embodiment, the valuable metal recovery alloy may be present in an amount of 20 to 35 wt% based on 100 wt% of the recovered material. Specifically, the valuable metal recovery alloy may be present in an amount of 25 to 30 wt%. The valuable metal recovery alloy may be a material comprising a valuable metal such as nickel, cobalt, and manganese.

[0032] By ensuring that the weight percent of the valuable metal recovery alloy in the recovered material satisfies the aforementioned range, the recovery rate of valuable metals such as nickel, cobalt, and manganese can be increased. While exceeding the upper limit of the aforementioned range can increase the recovery rate of valuable metals, it is uneconomical. Beyond the lower limit of the aforementioned range, the recovery rate of valuable metals is reduced.

[0033] In one embodiment, the metal recovery alloy may include a total amount of Ni, Co, and Mn of 90 wt% or more, and the remainder being impurities, based on 100 wt% of the total metal recovery alloy. Specifically, the total amount of Ni, Co, and Mn may be 90 to 96 wt%, and more specifically, 92 to 95 wt%.

[0034] When the total amount of Ni, Co, and Mn in the valuable metal recovery alloy satisfies the above-mentioned range, the recovery rate of valuable metal can be increased. When the total amount of Ni, Co, and Mn in the valuable metal recovery alloy exceeds the above-mentioned range, there is a problem of inefficiency or low recovery rate of valuable metal.

[0035] In one embodiment, nickel (Ni) may be included in an amount ranging from 50 to 60 wt% based on 100 wt% of the total weight of the metal recovery alloy. Specifically, nickel may be included in an amount ranging from 52 to 58 wt%.

[0036] When the content of the nickel is outside the upper limit of the above-mentioned range, there is a problem of a decrease in the leaching rate due to the formation of nickel carbide (Ni3C), and when the content of the nickel is outside the lower limit of the above-mentioned range, there is a problem of a decrease in the Ni recovery rate in leaching and solvent extraction.

[0037] In one embodiment, cobalt (Co) may be included in an amount ranging from 18 to 28 wt% based on 100 wt% of the total weight of the metal recovery alloy. Specifically, cobalt may be included in an amount ranging from 20 to 26 wt%.

[0038] If the cobalt content exceeds the upper limit of the above-mentioned range, there is a problem that the leaching rate due to the formation of cobalt carbide is reduced. If the cobalt content exceeds the lower limit of the above-mentioned range, there is a problem that the Co recovery rate in leaching and solvent extraction is reduced.

[0039] In one embodiment, manganese (Mn) may be included in an amount ranging from 10 to 20 wt% based on 100 wt% of the total weight of the metal recovery alloy. Specifically, cobalt may be included in an amount ranging from 12 to 18 wt%.

[0040] If the manganese content exceeds the upper limit of the aforementioned range, there is a problem of a decrease in the leaching rate due to the formation of manganese carbide. If the manganese content exceeds the lower limit of the aforementioned range, there is a problem of a decrease in the manganese recovery rate in leaching and solvent extraction.

[0041] In one embodiment, the lithium (Li) may be included in an amount ranging from 0.01 to 5 wt% based on 100 wt% of the total weight of the metal recovery alloy. Specifically, the lithium may be included in an amount ranging from 0.05 to 0.15 wt%.

[0042] Since the lithium satisfies the above range, there is an advantage in that the Li recovery rate can be maximized during the Li smelting process. If the upper limit of the above range is exceeded, there is a problem of reduced Ni and Co recovery rates, and if the lower limit of the above range is exceeded, there is a problem of reduced Li recovery rates during the Li smelting process, resulting in increased process costs.

[0043] In one embodiment, the metal recovery alloy may contain copper (Cu) in a range of 1.0 to 7 wt%. Specifically, the copper may be contained in a range of 3 to 5 wt%.

[0044] If the content of the copper is outside the upper limit of the above range, there is a problem of process cost due to an increase in the amount of CuSO4 precipitation in leaching and solvent extraction, and if the content of the copper is outside the lower limit of the above range, there is a problem of an increase in the amount of unreacted material due to difficulty in producing low-melting-point Ni-Co-Mn. In one embodiment, the copper can form an alloy by combining with nickel (Ni) among the valuable metals.

[0045] In one embodiment, the metal recovery alloy may contain carbon (C) in a range of 0.1 to 10 wt%. By satisfying the above range of carbon, the yield can be increased and the processing time in the wet process can be reduced. Specifically, the carbon may be contained in a range of 1 to 7 wt%.

[0046] If the upper limit of the above range is exceeded, the negative electrode material remains unreacted, preventing proper alloying and leaving valuable metal oxides within the positive electrode material. If the lower limit of the above range is exceeded, there is a risk of lithium loss due to high temperatures.

[0047] In one embodiment, the precious metal recovery alloy may contain aluminum (Al) in a range of 0.25 to 30 wt %. If the content of aluminum is outside the upper limit of the range, there is a problem of reduced Ni and Co recovery rates during the leaching and solvent extraction processes, and if the content of aluminum is outside the lower limit of the range, there is a problem of reduced Li recovery rates due to difficulty in producing LiAlO2.

[0048] In one embodiment, the lithium compound may comprise 25 to 50 wt% based on 100 wt% of the recovered material. Specifically, the lithium compound may comprise 30 to 40 wt%. In one embodiment, the lithium compound may be a compound comprising lithium. For example, the lithium compound may comprise lithium oxide, and the lithium oxide may comprise lithium aluminum oxide.

[0049] By ensuring that the lithium compound satisfies the aforementioned range, the recovery rate of lithium, one of the valuable metals, can be increased. If the lithium compound exceeds the lower limit of the aforementioned range, this results in a significant loss of Li to the NCM alloy or graphite, which reduces the Li recovery rate. In addition, when recovering Li in the downstream wet smelting process, the Li content of the input raw material decreases, which increases the process cost.

[0050] In one embodiment, the lithium compound may contain 10 to 20 wt% lithium (Li), based on 100 wt% of the lithium compound. Specifically, the lithium may contain 12 to 18 wt%.

[0051] If the lithium content is outside the upper limit of the above-mentioned range, it means that lithium does not react with Al to form a lithium compound in the form of LiAlO2, but rather the proportion of lithium hydroxide, lithium fluoride, lithium carbonate, etc. is high, which means that methods such as water leaching and acid leaching must be considered in the downstream wet refining process. If the lithium content is outside the lower limit of the above-mentioned range, it means that most of the lithium compounds were recovered in the form of LiAlO2 with low water solubility, which means that lithium compounds with high water solubility were dissolved in water during the sorting process, which means that lithium must be recovered again from the water used in the sorting process.

[0052] In one embodiment, the lithium compound may contain 20 to 30 wt% aluminum (Al) based on 100 wt% of the lithium compound. Specifically, the content may be 23 to 28 wt%. By satisfying the above-described range, a lithium compound may be formed through physical or chemical bonding with lithium, thereby increasing the yield of lithium.

[0053] If the content of the above aluminum exceeds the upper limit of the above range, there is a problem of increased cost of the Ni, Co solvent extraction and crystallization process and decreased Ni, Co recovery rate due to excessive generation of Al2(SO4)3 in the leaching and solvent extraction process. If the content of the above aluminum exceeds the lower limit of the above range, there is a problem of poor generation of Li-Al-O oxide due to insufficient aluminum content.

[0054] In one embodiment, the lithium compound may have a carbon (C) content of 1 to 7 wt% based on 100 wt% of the lithium compound. Specifically, the carbon (C) content may be 3 to 5 wt%. By satisfying the above-mentioned carbon content within the above-mentioned range, there is an advantage in optimizing the wet processing of the composition for recovering valuable metals.

[0055] When the content of the carbon exceeds the upper limit of the above range, there is a problem of a decrease in the leaching rate due to the formation of nickel carbide (Ni3C), and when the content of the carbon exceeds the lower limit of the above range, there is a problem of a decrease in the recovery rate of valuable metals such as Ni and Co in solvent extraction after the leaching process due to an increase in the content of other impurities such as Si.

[0056] In one embodiment, the graphite-based material may comprise 25 to 50 wt% based on 100 wt% of the recovered material. Specifically, the graphite-based material may comprise 30 to 40 wt%. The content of the graphite-based material may be such that a large amount of graphite-based material is produced as a high-temperature reduction reaction is performed in a low-oxygen content range that reduces the generation of carbon dioxide. By satisfying the aforementioned range of the graphite-based material, the recycling yield of graphite-based material that can be used as an anode material can be increased.

[0057] If the above graphite-based material exceeds the upper limit of the aforementioned range, the graphite content increases excessively, resulting in a problem of reduced recovery of valuable metals. If the above graphite-based material exceeds the lower limit of the aforementioned range, the graphite recovery rate is low.

[0058] In one embodiment, the graphite material may contain a carbon (C) content of 80 to 90 wt% and a remainder of impurities. The carbon (C) content may be 83 to 87 wt%. By satisfying the above-described carbon content within the above-described range, high-purity graphite containing carbon can be obtained.

[0059] If the carbon content exceeds the upper limit of the aforementioned range, there is a problem of a reduced recovery rate of valuable metals. If the carbon content exceeds the lower limit of the aforementioned range, there is a problem of a low recovery rate of graphite.

[0060] In one embodiment, the graphite-based material may have a copper (Cu) content of 13 to 25 wt% based on 100 wt% of the graphite-based material. Specifically, the copper content may be 15 to 20 wt%. 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 increases during the process of refining graphite into high-purity graphite.

[0061] Figure 2 is a flowchart of a battery processing method according to one embodiment of the present invention.

[0062] Referring to FIG. 2, a battery processing method includes the steps of preparing a product obtained by subjecting shredded materials recovered from a spent battery to a high-temperature reduction heat treatment, the step of magnetically separating the product, and the step of crushing a magnetic product among the magnetically separated products to separate magnetic substances and non-magnetic substances. The battery processing method of the present invention provides a battery processing method capable of increasing the recovery rate of valuable metals by efficiently performing magnetic separation from the product obtained by subjecting shredded materials recovered from a spent battery to a high-temperature reduction heat treatment. The valuable metal of the present invention may refer to an expensive metal component included in a battery, and may refer to nickel, cobalt, manganese, aluminum, copper, and lithium.

[0063] The step of preparing a product by high-temperature reduction heat treatment of the recovered shredded material from a used battery includes the steps of preparing a battery, the step of crushing the battery into battery shredded material, and the step of high-temperature heat treatment of the crushed battery shredded material.

[0064] In the step of preparing the battery, the battery may be a method for processing various types of batteries containing lithium ions, and the battery may be, for example, a lithium secondary battery separated from an automobile, a secondary battery separated from an electronic device such as a mobile phone, a camera, or a laptop, and specifically, a lithium secondary battery. More specifically, the battery utilizes a waste battery, and thus has the advantage of being environmentally friendly.

[0065] In one embodiment, during the battery preparation step, the battery may include lithium (Li) and aluminum (Al). By coexisting lithium and aluminum within the battery, the lithium and aluminum may be physically and / or chemically bonded in the resulting product after battery processing.

[0066] The step of shredding the battery may refer to a process of applying shock or pressure to the battery so that a portion of the battery detaches from the battery. In one embodiment, the step of shredding the battery may refer to a process of crushing the battery, a process of cutting the battery, a process of compressing the battery, or a combination thereof. Specifically, the step of shredding may include any process that destroys the battery to obtain small-sized shredded materials.

[0067] In one embodiment, the step of crushing the battery may include any process of compressing the prepared battery or applying an external force, such as a shear force or tensile force, to destroy the battery. The step of crushing the battery may be performed, for example, using a crusher.

[0068] In one embodiment, the step of crushing the battery may be performed at least once. Specifically, the step of crushing may be performed at least once, either continuously or discontinuously.

[0069] In one embodiment, the step of crushing the battery may be performed under conditions in which an inert gas, carbon dioxide, nitrogen, water, or a combination thereof is supplied, or under vacuum conditions of 100 torr or less. When performed under the aforementioned conditions, the supply of oxygen can be suppressed, preventing the electrolyte from reacting with oxygen, thereby preventing an explosion caused by the reaction, and suppressing the evaporation of the electrolyte, thereby preventing the generation of flammable gases such as ethylene, propylene, or hydrogen.

[0070] The step of high-temperature heat treatment of the shredded battery scrap may include placing the shredded battery scrap in a heating furnace capable of raising the temperature to a temperature higher than the melting point of the shredded battery. The shredded battery scrap may include, for example, valuable metals such as Ni, Co, Mn, and Li. The high-temperature heat treatment may involve heat treatment conditions that perform a high-temperature reduction reaction without melting the battery.

[0071] In one embodiment, the step of high-temperature heat treatment of the battery shredded material may be performed in a gas atmosphere containing at least one of an inert gas, carbon dioxide, carbon monoxide, hydrocarbon gas, and oxygen. The inert gas may, for example, contain at least one of argon and nitrogen. By performing a reduction reaction of the shredded material in the gas atmosphere, the recovery rate of valuable metal elements contained in the battery shredded material can be increased.

[0072] In one embodiment, the step of high-temperature heat treating the Ni, Co, Mn, and Li-containing battery waste may be performed in a gas atmosphere comprising at least one of an inert gas, carbon dioxide, carbon monoxide, and a hydrocarbon gas; and oxygen. In one embodiment, the gas atmosphere may be performed in a gas atmosphere in which the oxygen concentration ranges from 0.1 to 2.0 vol%. Specifically, the gas atmosphere may be performed in a gas atmosphere in which the oxygen concentration ranges from 0.4 to 1.2 vol%.

[0073] When the oxygen concentration exceeds the upper limit of the above-mentioned range, there is a problem that the reaction of Li2O + C + O2(g) = Li2CO3 is promoted as the oxygen concentration increases, but at the same time, LiAlO2 and Li5AlO4 decrease. Specifically, when the oxygen concentration exceeds the upper limit of the above-mentioned range, there is a problem that carbon dioxide is excessively formed during the reduction reaction and disappears by gasification together with lithium, or the production of Li2CO3(s) increases excessively, making recovery by acid leaching difficult. When the oxygen concentration exceeds the lower limit of the above-mentioned range, there is a problem that the lithium recovery rate decreases.

[0074] In one embodiment, the step of high-temperature heat treatment of the battery shreds may be performed in a range of 600 to 1,500°C. Specifically, the step of high-temperature heat treatment may be performed in a range of 900 to 1,500°C, more specifically in a range of 1,100 to 1,500°C, and even more specifically in a range of 1,300 to 1,500°C. In the step of high-temperature heat treatment of the battery shreds, as the temperature increases, LiAlO2(s)+2Li2CO3(s) = Li5AlO4+2CO2(g) reaction is used to generate Li5AlO4, but the LiF(g) vaporization reaction is promoted, so that when performed in the above-described range, the yield of lithium can be improved.

[0075] Beyond the upper limit of the above range, there is a problem of lithium loss due to lithium vaporization. Specifically, beyond the upper limit of the above range, there is a problem of lithium recovery rate being reduced due to lithium loss as the LiF(g) vaporization reaction is excessively promoted.

[0076] If the lower limit of the above range is exceeded, the sintering and reduction of the alloy elements do not proceed smoothly, and a stabilized lithium-containing compound is not formed, which makes it difficult to recover the stabilized compound when recovering the lithium compound in the future. Specifically, if the lower limit of the above range is exceeded, MnO among the Li-containing Ni, Co, and Mn oxides in the positive electrode material is not dissociated, and MnAl2O4 is generated due to the reaction MnO(s)+2Al(s)+3 / 2O2=MnAl2O4(s), which reduces the lithium concentration in the lithium compound, resulting in a problem of a lower lithium recovery rate.

[0077] The step of magnetically separating the high-temperature heat-treated product may be performed by magnetically separating the product to separate the first magnetic material having magnetism and the first non-magnetic material having non-magnetism. Magnetic separation utilizes a magnetic material to separate particles through contact with the magnetic material, and various types of magnetic separation methods may be applied.

[0078] The first magnetic body may be a composition comprising a core portion and a shell portion disposed on the core portion, specifically a composition comprising valuable metals such as Ni, Co, and Mn. The core portion may include a valuable metal recovery alloy. The core portion of the composition for recovering valuable metals may be recovered from a cathode material component in a spent battery.

[0079] The shell portion is disposed on the core portion and may include a lithium compound. Specifically, when recovering valuable metals from a spent battery, the valuable metals in the spent battery exist in the form of oxides and are reduced by graphite in the negative electrode material through a high-temperature heat treatment process. At this time, the copper current collector may melt and exist in a liquid state, and may play a role in agglomerating the reduced valuable metals. The copper current collector and the aluminum current collector may partially perform a reduction reaction with the positive electrode oxide, and the remainder may react with lithium, so that a lithium-containing oxide-type compound may remain. A detailed description thereof will be described later with reference to FIGS. 3A and 3B and FIG. 4.

[0080] The second non-magnetic material may include at least one of a compound including Li that is not bound to a metal in the magnetic separation step and a graphite material including carbon.

[0081] In one embodiment, the magnetic separation step may be performed at a magnetic strength range of 1,000 to 5,000 Gauss. Specifically, the magnetic separation step may be performed at a magnetic strength range of 2,000 to 3,000 Gauss.

[0082] There is an advantage in that the magnetic separation step is performed within the above magnetic strength range, thereby efficiently separating valuable metals. If the magnetic strength range exceeds the upper limit of the above range, even trace amounts of valuable metals are recovered, thereby increasing the recovery rate, but the grade of the recovered valuable metals is lowered and the amount of impurities such as graphite and copper increases, thereby lowering the process efficiency in the next process, the wet refining process, and increasing the processing cost. If the magnetic strength range exceeds the lower limit of the above range, there is a problem in that the recovery rate of valuable metals is lowered, thereby increasing the loss of Ni, Co, and Mn.

[0083] The step of separating a magnetic substance and a non-magnetic substance by crushing a magnetic substance among the magnetically separated products may be a step of crushing a magnetically separated first magnetic substance. The first magnetic substance refers to a core portion including a valuable metal alloy and a compound including lithium disposed on the core portion, as described above. The core portion and the shell portion of the first magnetic substance may be separated through a crushing process. Specifically, the first magnetic substance may be separated into a second magnetic substance and a second non-magnetic substance through the crushing process described above. The second magnetic substance refers to, for example, an NCM alloy including Ni, Co, and Mn, and the second non-magnetic substance may be a compound including lithium, for example, lithium aluminate (LiAlO2).

[0084] 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 simultaneously, thereby increasing the lithium recovery rate and reducing the amount of lithium lost.

[0085] In one embodiment, the pulverization step uses equipment that pulverizes using shear force in the form of a vertical attrition mill, and the RPM of the agitator for the vertical attrition mill can be performed in a shear force range of 1 to 5 m / sec based on the tip speed. Specifically, the pulverization step can be performed in a shear force range of 2 to 3 m / sec based on the tip speed. Since the pulverization step is performed in the above-described shear force range, the NCM alloy, which is the core portion of the first magnetic body, is not pulverized, and only the compound including lithium, which is the shell portion disposed on the core portion, can be pulverized into fine powder.

[0086] At this time, Tip Speed ​​can be calculated using the following formula: Tip Speed ​​= Pi × Impeller Diameter × RPM / 100

[0087] In one embodiment, when the shear force exceeds the upper limit of the aforementioned range, the shell portion of the first magnetic body is separated and then pulverized to the magnetic core portion inside, and since the core portion is a ductile metal, there is a problem in that the spherical particles grow into a plate shape during rolling and then are pulverized again into particles of a smaller size. At this time, there is a problem in that the recovery rate is reduced in the process of separating the magnetic body of the core portion and the lithium compound of the shell portion using particle size. When the shear force exceeds the lower limit of the aforementioned range, there is a problem in that the lithium compound of the shell portion is not pulverized and is recovered again together with the magnetic body of the core portion.

[0088] In one embodiment, the crushing step may be performed for 20 to 80 minutes. Specifically, the crushing step may be performed for 30 to 60 minutes. As the crushing step is performed within the aforementioned range, the recovery rate of valuable metals such as Ni, Co, Mn, and Li may be increased.

[0089] In the above-mentioned crushing step, if the upper limit of the above-mentioned range is exceeded, the magnetic material including the core magnetic material and the shell lithium compound is excessively crushed, and rolling is performed into a plate-like shape due to ductility, and the plate-like particles are continuously over-crushed, and are split again into fine particles, so that the effect of the magnetic force is insufficient in further magnetic separation. In the above-mentioned crushing step, if the lower limit of the above-mentioned range is exceeded, there is a problem that the shell part including the lithium compound is not easily separated from the magnetic material having the core-shell structure.

[0090] In one embodiment, after the crushing step, a step of further separation by any one of particle size separation, flotation, and magnetic separation may be included. The flotation separation is a method of separating particles by considering differences in specific gravity between materials. For example, the particles may be separated based on the specific gravity of the particles corresponding to a specific solvent by utilizing a specific solvent.

[0091] When the core and shell portions of the first magnetic body are separated through the above-described pulverization step, the valuable metal alloy is separated into large particle sizes due to the elongation of the particles due to the ductility of the metal, and the lithium-containing compound can be pulverized into a fine powder form with a small particle size. Specifically, the first magnetic body can separate a lithium-containing compound having a particle size of less than 70 to 80 μm and a valuable metal alloy having a particle size of 70 to 80 μm or more.

[0092] In one practical example, the core and shell portions separated through the above-described crushing step can be subjected to particle size separation based on a particle size of 70 to 80 μm. The lithium-containing compound, which is the shell portion, has a particle size smaller than the aforementioned particle size standard, and the valuable metal alloy, which is the core portion, has a particle size larger than the aforementioned particle size, so that the valuable metal alloy and the lithium-containing compound can be easily separated through particle size separation.

[0093] In another embodiment, the core and shell separated through the above-described crushing step may be subjected to magnetic separation. Through the magnetic separation, a valuable metal alloy containing magnetic Co and a non-magnetic lithium-containing compound can be easily separated.

[0094] In another embodiment, the core and shell portions separated through the above-described crushing step may be subjected to flotation. Through the flotation, the core portion containing the precipitated valuable metal and the floating lithium-containing compound can be easily separated.

[0095] In one embodiment, the method may include a step of separating a first non-magnetic material. The first non-magnetic material, which includes graphite, may be separated from the non-magnetic material separated in the first magnetic separation step.

[0096] In one embodiment, the flotation step may be a step of separating a float containing graphite and a precipitate containing valuable metal. Specifically, the flotation step may be a step of float-separating hydrophobic graphite from the first non-magnetic body and precipitating and separating a lithium-containing compound and a particulate valuable metal alloy.

[0097] In one embodiment, a step may be performed to magnetically separate the sediment to recover a material containing valuable metals, and then crushing the recovered material together with the magnetic product. A detailed description of the crushing step is as described above.

[0098] In one embodiment, the method may include a step of drying the final product after the step of crushing the magnetic product among the magnetically separated products to separate the magnetic material and the non-magnetic material. Through the drying step, the valuable metal alloy, the compound including lithium, and the graphite may be dried into a powder form.

[0099] In one embodiment, the step of drying the final product may be performed at a temperature ranging from 80 to 200° C. Specifically, the step of drying the final product may be performed at a temperature ranging from 100 to 150° C.

[0100] If drying is performed outside the upper limit of the above temperature range, there is a problem that combustible materials such as graphite may burn. If drying is performed outside the lower limit of the above temperature range, the moisture in the final product, the powder particles, is not completely dried, and a product with a high moisture content is discharged, which increases the acid usage in the leaching process of the downstream wet refining process.

[0101] FIG. 3a and FIG. 3b are XRD analysis results of a composition for recovering valuable metals formed after heat treatment according to one embodiment of the present invention.

[0102] Referring to FIGS. 3A and 3B , it can be confirmed that the composition for recovering valuable metals that has been subjected to reduction heat treatment at high temperatures does not form an alloy by being reduced, such as Ni, Co, and Mn, but rather combines with the Al component in the battery to form a lithium-containing compound, for example, lithium oxide. It can be confirmed that the lithium oxide is formed of, for example, LiAlO2, Li5AlO4, and Li2CO3. In one embodiment, the composition for recovering valuable metals may further include LiF. The LiF may be a result of the remaining electrolyte amount depending on the degree of pretreatment.

[0103] In one embodiment, LiAlO2 can include XRD peaks of at least one of 20.5 to 21.5°, 29.0 to 29.5°, 31.5 to 32.0°, 32.2 to 33.0°, 60.5 to 61.5°, and 70.0 to 72.0°. Li5AlO4 can include XRD peaks of at least one of 19.5 to 20.2° and 21.6 to 22.2°.

[0104] The LiAl5O8 composition may include at least one of XRD peaks from 15.0 to 17.4°, from 24.2 to 26.1°, from 31.4 to 33.1, from 36.2 to 40.3, from 46.1 to 47.3, from 61.1 to 63.4, and from 66.2 to 68.7. The LiF composition may include at least one of XRD peaks from 37.5 to 40.2°, from 43.9 to 46.5°, and from 64.5 to 66.5°.

[0105] The Li3PO4 composition may include at least one of XRD peaks from 29.2 to 40.1° and from 52 to 77.1°. The Li2SiO3 composition may include at least one of XRD peaks from 17.7 to 20.1°, 26.1 to 29.5°, 32.2 to 36.2, and 37.6 to 39.7. The Li4SiO4 composition may include at least one of XRD peaks from 16.2 to 18.3°, 21.4 to 25.2°, 34.2 to 39.7, and 59.2 to 63.4.

[0106] The Li2Si2O5 composition may include at least one of XRD peaks from 16.2 to 18.3°, from 21.4 to 25.2°, from 34.2 to 39.7°, and from 59.2 to 63.4°. The Li2CO3 composition may include at least one of XRD peaks from 24.0 to 26.0°, from 27.0 to 29.0°, from 34.0 to 36.0°, and from 37.0 to 39.0°.

[0107]

[0108] FIG. 4 is an SEM photograph of a composition for recovering valuable metals according to one embodiment of the present invention.

[0109] Referring to FIG. 4, a composition for recovering valuable metals 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 metal of the present invention may refer to an expensive metal component contained in a battery, and may refer to nickel, cobalt, manganese, aluminum, copper, and lithium. The core portion of the composition for recovering valuable metals may be recovered from a cathode material component in a spent battery.

[0110] The shell portion is disposed on the core portion and may include a lithium compound. Specifically, when recovering valuable metals from a spent battery, the valuable metals in the spent battery exist in the form of oxides and are reduced by graphite in the negative electrode material through a high-temperature heat treatment process. At this time, the copper current collector may melt and exist in a liquid state, and may play a role in agglomerating the reduced valuable metals. The copper current collector and the aluminum current collector may partially perform a reduction reaction with the positive electrode oxide and the remainder may react with lithium, so that a lithium-containing oxide-type compound may remain.

[0111] In one embodiment, the content of lithium (Li) in the lithium compound may be 4 to 35 wt%, specifically 4 to 25 wt%, based on the total 100 wt%. By satisfying the above-mentioned range of Li content in the lithium compound, a composition including a lithium-containing compound having a high lithium content and an excellent lithium recovery rate can be satisfied. When the content of Li exceeds the upper limit of the above-mentioned range, there is a problem that the lithium recovery rate is lowered because a large amount of compounds that are difficult to recover due to water solubility problems are generated as the Li2O content increases, and when the content of Li exceeds the lower limit of the above-mentioned range, there is a problem that the lithium recovery rate is low and the utility value is not high.

[0112] In one embodiment, the lithium compound may include at least one of LiAlO2, Li5AlO4, LiAl5O8, Li2CO3, LiF, Li3PO4, Li2SiO3, Li4SiO4, and Li2Si2O5. In one embodiment, the lithium compound may include lithium aluminum oxide.

[0113] The lithium compound may be, for example, lithium oxide. The lithium-aluminum oxide may be implemented in the form of an oxide in which lithium contained in the composition is physically or chemically bonded.

[0114] In one embodiment, the lithium compound may include lithium aluminum oxide. Specifically, the content of lithium aluminum oxide may range from 45.0 to 97.0 wt% based on 100 wt% of the valuable metal recovery composition. Specifically, the content may range from 70 to 90 wt%.

[0115] If the content of the lithium aluminum oxide is outside the upper limit of the above-mentioned range, there is a problem that lithium hydroxide, lithium carbonate, lithium fluoride, etc., which have high water solubility, are dissolved in large amounts in water during the sorting process. If the content of the lithium aluminum oxide is outside the lower limit of the above-mentioned range, it means that most of the lithium compounds are recovered in the form of LiAlO2, which has low water solubility, and that the lithium compounds with high water solubility are dissolved in water during the sorting process, which causes a problem that lithium must be recovered again from the water used during the sorting process.

[0116] In one embodiment, the lithium compound may include a lithium and silicon-containing oxide. Specifically, the content of the lithium and silicon-containing oxide may range from 2 to 30 wt% based on 100 wt% of the valuable metal recovery composition. Specifically, the content may range from 10 to 25 wt%. By satisfying the above-described range of lithium and silicon-containing oxide, a stable product can be secured under a high temperature and appropriate oxygen concentration atmosphere, thereby increasing the yield of lithium during acid leaching.

[0117] If the content of the lithium and silicon-containing oxides exceeds the upper limit of the above-mentioned range, there is a problem that the productivity of the reactor decreases and energy costs increase because it means that it has been exposed to the maximum temperature for a long time during the high-temperature reduction reaction. If the content of the lithium and silicon-containing oxides exceeds the lower limit of the above-mentioned range, there is a problem that the recovery rate of lithium decreases because there is not enough heat energy for lithium to react with aluminum or silicon to produce lithium compounds such as lithium aluminate, or the temperature of the reactor is too high, so that lithium is volatilized and removed.

[0118] In one embodiment, the metal recovery composition may contain no more than 10 wt% silicon (Si), based on 100 wt% of the metal recovery composition. Specifically, the silicon may be no more than 1.0 wt%, and more specifically, no more than 0.5 wt%.

[0119] If the above silicon (Si) content exceeds the upper limit of the above-mentioned range, there is a problem that the process time and cost increase in removing silicon to battery grade in the downstream wet refining process. If the above silicon (Si) content exceeds the lower limit of the above-mentioned range, there is a problem that the remaining weight % of silicon in the input raw material is dispersed into graphite and lithium compounds, and the process time and cost increase in the refining and refining process of graphite and lithium compounds.

[0120] In one embodiment, Li2CO3 may be included in an amount of 30% or less based on 100% by weight of the entire composition. The Li2CO3 may be included in an amount of 15.0% or less, more specifically, 5% or less. By ensuring that the content of Li2CO3 satisfies the aforementioned range, there is an advantage in preventing the production of a large amount of a compound that is difficult to recover due to water solubility issues.

[0121] In one embodiment, LiF may be included in an amount of 30 wt% or less based on 100 wt% of the total composition. The LiF may be included in an amount of 6.5 to 24.0 wt%, more specifically, 6.5 to 15 wt% or less based on 100 wt% of the total composition. By ensuring that the content of LiF satisfies the above-described range, there is an advantage in preventing the production of a large amount of a compound that is difficult to recover due to water solubility issues.

[0122] If the LiF exceeds the upper limit of the aforementioned range, there is a problem that the pH is difficult to adjust due to the mixing of sulfate ions and fluoride ions during sulfuric acid leaching, thereby reducing the Li recovery rate. If the LiF exceeds the lower limit of the aforementioned range, there may be a problem that the leaching process time is delayed due to the increase in Li2SiO3, Li4SiO4, and Li2Si2O5, etc., making sulfuric acid leaching difficult.

[0123] In one embodiment, the total content of Li2CO3 and LiF may be 50% or less, based on 100 wt% of the entire composition. Specifically, the total content may be 0.5 to 50%, and more specifically, the content may be 0.5 to 30% or less.

[0124] If the total content exceeds the upper limit of the above-mentioned range, a large amount of compounds that are difficult to recover due to water solubility issues are generated, which makes it difficult to recover Li. If the total content exceeds the lower limit of the above-mentioned range, the compounds such as Li2SiO3, Li4SiO4, and Li2Si2O5 increase, making sulfuric acid leaching difficult, which causes a problem in that the leaching process time is delayed.

[0125] By satisfying the above-mentioned range of the combined amount of Li2CO3 and LiF, it is possible to prevent the production of a large amount of compounds that are difficult to recover due to water solubility issues, and by appropriately adjusting the high temperature and oxygen concentration, it is possible to produce a large amount of stable compounds with excellent leaching rates in sulfuric acid, thereby increasing the efficiency of lithium recovery.

[0126] In one embodiment, Li3PO4 may be included in an amount of 10 wt% or less based on 100 wt% of the entire composition. The Li3PO4 may be included in an amount of 5 wt%, specifically, 3 wt% or less, and more specifically, 0.1 to 0.7 wt%, based on 100 wt% of the entire composition. When the Li3PO4 content satisfies the above-mentioned range, PO is present during acid leaching. 3- The problem of LiOH being generated when removing impurities and leaching behavior according to pH change by anions can be prevented from reducing the Li recovery rate. When the Li3PO4 content satisfies the above-mentioned range, PO is generated during acid leaching. 3- It can prevent the Li recovery rate from decreasing due to problems such as leaching behavior according to pH change by anions and LiOH generation during impurity removal.

[0127]

[0128] Hereinafter, preferred embodiments and comparative examples of the present invention are described. However, the following examples are only preferred embodiments of the present invention, and the present invention is not limited to the following examples.

[0129] <Experimental Example> - Control of Waste Battery Conditions

[0130] Battery shredders can be shredded to a maximum length of 100 mm or less through a shredding process. Specifically, the optimal size for battery shredders is 10 to 40 mm in maximum length and width. This is to prevent the risk of fire during battery shredding.

[0131] When the reaction distance between the positive and negative current collectors is less than 10 mm, when the battery shreds are heat-treated and reduced, a composition can be obtained in which lithium reacts with aluminum and a lithium compound is bonded to the surface of the precious metal recovery alloy. Specifically, when the reaction distance is greater than 10 mm, there is a problem in that the lithium in the aluminum and the positive electrode, electrolyte, and negative electrode does not react with the aluminum but volatilizes, thereby lowering the purity of the lithium reaction with the aluminum.

[0132]

[0133] Experimental Example 1

[0134] 1. Step of preparing a composition for recovering valuable metals

[0135] Prepare a cell, module, or pack, which is a spent electric vehicle battery, containing a positive electrode material containing lithium ions, a negative electrode material made of graphite, an aluminum current collector, a separator, an electrolyte, and a copper current collector. The spent battery is frozen at -30°C or lower and then crushed, or after being discharged under salt water discharge or electric discharge conditions, the spent battery is crushed using a shredder under atmospheric conditions or inert gas conditions so that the longest length or width of the battery is 100 mm or less.

[0136] After obtaining a composition for recovering valuable metals by the method described above, the crushed battery waste was heat-treated at 1,300°C under an oxygen partial pressure of 0.5% to perform a reduction process. After the reduction process, a composition for recovering valuable metals, comprising a core portion including valuable metals as described above and a shell portion including a lithium-containing compound on the core portion, was produced.

[0137] Table 1 below shows the components and contents of the composition for recovering valuable metals produced by the above-described method.

[0138] The components and contents in Table 1 below were measured using quantitative analysis methods such as (ICP-OES) equipment and C / S analysis equipment.

[0139] Li(wt%)Ni(wt%)Co(wt%)Mn(wt%)Al(wt%)Cu(wt%)C(wt%)RemarksExperimental Example 13.9119.856.136.567.2011.4333.70Example

[0140] 2. First magnetic separation stage: The composition for recovering precious metals that had undergone a high-temperature reduction process was separated into magnetic and non-magnetic substances using a magnetic separator having a magnetic strength of 3000 Gauss.

[0141] Experimental example 2_1 in Table 2 below shows the components and contents of magnetic and non-magnetic materials separated by passing through a 3000 Gauss magnetic separator.

[0142] Magnetic Total content (wt%) Li (wt%) Ni (wt%) Co (wt%) Mn (wt%) Al (wt%) Cu (wt%) C (wt%) Note Experimental example 2_1 Magnetic 64.00 4.96 30.26 9.35 9.75 7.62 12.36 10.30 Example Experimental example 2_2 Non-magnetic 36.00 2.04 1.34 0.40 0.89 6.44 9.77 75.30 Example

[0143] Looking at Table 2 above, in the case of the magnetic material separated through magnetic separation as in Experimental Example 2_1, it was confirmed that it contained NCM metal, which is a valuable metal, and had a high content of Li, Ni, Co, and Mn. In the case of the particles separated as non-magnetic material through magnetic separation as in Experimental Example 2_2, it was confirmed that the majority of Li and Al and graphite particles were separated and had a high content of C.

[0144] 3_1. Floating selection stage

[0145] As in Experimental Example 2_2, non-magnetic materials separated through magnetic separation were subjected to flotation using the Denver Sub_A flotation separation equipment of Experimental Example 3_1, with the following methods: 30% ore concentration, 500 rpm impeller rotation speed, 0.1 ml / 100 g kerosene, and 0.1 ml / 100 g MIBC.

[0146] Through the above floating selection, light graphite powder floats to the top of the equipment and is separated to recover graphite.

[0147] Table 3 below shows the components and contents of the results obtained through the flotation selection process.

[0148] PrecipitationTotal content(wt%)Li(wt%)Ni(wt%)Co(wt%)Mn(wt%)Al(wt%)Cu(wt%)C(wt%)RemarksExperimental example 3_1 Suspension(O / F)81.110.440.330.170.120.481.2591.32ExampleExperimental example 3_2 Precipitation(U / F)18.891.061.040.371.0910.0118.045.75Example

[0149] Looking at Table 3 above, the C content of the material floating in the overflow (O / F) was 92.5%, which is a significant increase compared to the C content of the initial battery shreds (35.07%) and the C content of the raw material separated into non-magnetic substances through magnetic separation (75.30%) and fed into the flotation separator. In addition, the C content of the sediment remaining in the underflow (U / F) was 5.75%, indicating that most of the hydrophobic C was recovered as floating matter. In addition, looking at the lithium content ratio of the floating matter and the sediment, it can be seen that most of the lithium did not float but remained in the sediment, allowing for efficient separation of C and lithium through flotation. In addition, judging from the high aluminum content of the sediment, it is believed that most of the lithium remained in the sediment in the form of LiAlO2. In addition, Cu did not float but mostly remained in the sediment, and the content was 18.04%. 4. Crushing stage and secondary magnetic separation stage

[0150] 2. The magnetic material that has gone through the magnetic separation step is pulverized using an Attrition Mill, which is a vertical stirring mill, at 500 rpm, 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 composition for recovering valuable metals, which is composed of a core part containing valuable metals and a shell part containing a compound containing lithium arranged on the core part. It was confirmed that the core part and the shell part are separated during the pulverization process.

[0151] Table 5 below shows the components and contents of the resultant product obtained by separating the magnetic material including the core portion and the shell portion and separating the resultant product according to particle size.

[0152] Total magnetic content (wt%)Li(wt%)Ni(wt%)Co(wt%)Mn(wt%)Al(wt%)Cu(wt%)RemarksExperimental example 4_1Magnetic67.970.3742.1912.9413.512.153.79ExampleExperimental example 4_2Nonmagnetic32.0314.561.151.401.2117.9627.45Example

[0153] Looking at Table 5 above, in order to separate the alloy core containing valuable metals and lithium compounds from the resultant product after the crushing process, a magnetic separator of 3000 Gauss was used to separate the magnetic and non-magnetic materials. As a result, it was confirmed that the core containing valuable metals, Experimental Example 4_1, contained excessive amounts of Ni, Co, and Mn. Experimental Example 4_2, which was separated as a non-magnetic material, was the result of the shell containing lithium being crushed, and it was confirmed that the lithium content was high. In the product recovered as a result of the magnetic separation, the shell part in the form of an oxide is crushed during the crushing process, and the core part, which has ductility, is continuously crushed inside the crusher and rolled into a plate shape, which causes the particle size to increase and the thickness to decrease compared to the initial particle size. In contrast, since the shell part is brittle in the form of an oxide, the particle size decreases as the crushing time increases due to continued crushing. 5. Secondary Separation Stage

[0154] Experimental Example 4_1, which has gone through the crushing step, can be separated by particle size separation using the difference in the crushing characteristics of the core alloy and the shell oxide compound, but it is more preferable to perform secondary separation through a magnetic separation process with a magnetic strength of 3000 Gauss using the magnetic property of the core alloy. In this case, if separation is performed using magnetic separation, the recovery rate of valuable metals in the core can be further increased compared to particle size separation. If particle size separation is applied, separation should be performed using a mesh having a mesh size of 75 ㎛ or 45 ㎛, and at this time, coarse particles are recovered as NCM alloy and fine particles are recovered as Li oxide.

[0155]

[0156] 6. Drying stage

[0157] The magnetic material containing Ni, Co, and Mn, the non-magnetic material containing Li, and the graphite separated through the above-described steps were dried to 5% or less through a drying step using hot air at 100 to 200°C after reducing the moisture content to 30% using a drum-type dehydrator or a centrifugal dehydrator, and then recovered.

[0158] Table 5 below shows the components and contents of the final product recovered through the steps described above.

[0159] Main composition Total content (wt%) Li (wt%) Ni (wt%) Co (wt%) Mn (wt%) Al (wt%) Cu (wt%) C (wt%) Non-high-value metal alloy 48.35 0.37 42.19 12.94 13.5 12.15 3.7 9 7.16 Experimental example 4_1 Lithium compound 24.9 5 9.5 5 1.11 1.0 2 1.17 15.0 4 2 3.96 12.70 Experimental example 4_2 and Experimental example 3_2 Graphite 26.6 9 0.4 4 0.3 3 0.17 0.12 0.4 8 1.2 5 9 1.3 2 Experimental example 3_1

[0160] Looking at Table 5 above, the valuable metal alloy containing Ni, Co, and Mn as main components can be recovered from the magnetic material separated through magnetic separation, pulverization, and magnetic separation steps, as in Experimental Example 4_1. The lithium compound contains lithium as its main component and can be recovered from the sum of the non-magnetic material separated through magnetic separation, pulverization, and magnetic separation steps, as in Experimental Example 4_2, and the precipitated material through flotation, as in Experimental Example 3_2. Graphite can be recovered by separating the floating material through flotation, as in Experimental Example 3_1. In this way, it was confirmed that by going through the battery processing method described above, the valuable metal alloy containing valuable metals such as Ni, Co, and Mn can be recovered, and at the same time, the lithium compound having a high lithium content can be separated, thereby increasing the recovery rate of the valuable metals Li, Ni, Co, and Mn. In addition, it was confirmed that the recovery rate of graphite that can be used as a negative electrode material can be increased by separating the graphite separately. <Experimental Example 2>: Changes in the components of magnetic and non-magnetic materials according to changes in magnetic strength

[0161] Table 6 below shows the changes in the components of magnetic and non-magnetic materials according to changes in magnetic strength during the first magnetic selection.

[0162] Magnetic strength [G] Classification Weight [wt%] LiNiCoMnAlCu [WT%] DIST,% [WT%] DIST,% [WT%] DIST,% [WT%] DIST,% [WT%] DIST,% [WT%] DIST,% 500 Magnetic substance 7.2 32.66 35.93 46.40 29.85 16.00 36.61 13.30 38.17 5.65 44.93 4.90 6.98 Non-magnetic substance 92.77 1.50 64.078 .5070.152.1663.391.6861.830.5455.075.0993.021000Magnetic32.532.9260.3038.4087.8513.3091.1811.1086.166.4633.268.3846.49Nonmagnetic67.472.5139.702.5612.150.628.820.8613.846.2566.744.6553.512000Magnetic36 .113.0959.6636.8096.1212.4097.6310.7094.097.2475.335.9447.04Non-magnetic63.891.1540.340.843.880.172.370.385.911.3424.673.7852.963000Magnetic36.193.2642.9833.4092.4811.2095.6.9.5491.547.2084.666.01 48.98 Non-magnetic 63.8 11.25 57.02 1.5 47.5 20.29 4.37 0.50 8.46 0.74 15.34 3.55 51.02 5000 Magnetic 35.6 13.08 33.50 91.82 11.30 94.27 9.55 89.95 6.77 39.77 5.04 37.28 Non-magnetic 64.39 2.26 1.65 8.18 0.38 5.73 0.59 10.05 5.67 60.23 4.69 62.72

[0163] Referring to Table 6 above, when examining the changes in the components of magnetic and non-magnetic materials according to the change in magnetic strength during the first magnetic separation, at magnetic strengths of 500 and 1000 Gauss (G), which are weak magnetic strengths, the grade (Grade) of NCM cathode material recovered as a magnetic product is high, but the recovery rate (Dist.) is low at 90% or less, and the Li content and recovery rate are low. However, at 2000 Gauss or higher, it can be confirmed that most NCM cathode material is recovered as a magnetic material.

[0164] <Experimental Example 3>: Secondary magnetic separation after controlling the crushing conditions

[0165] Table 7 below shows the results of separating the crushed product into magnetic and non-magnetic materials using a 3000 Gauss magnetic separator after crushing the magnetic material after the first magnetic separation.

[0166] At this time, a vertical stirring ball mill (Attrition Mill) was used as the pulverizer, and the pulverization conditions were RPM 500 (Tip Speed ​​2.65 m / sec), the pulverization container size was 1 L, the solid content concentration was 30%, and the pulverization time was 0 to 90 minutes. The magnetic and non-magnetic substances were analyzed according to the pulverization time.

[0167] Grinding time [min] ClassificationWeight [wt%]LiNiCoMnAlCu[WT%]DIST,%[WT%]DIST,%[WT%]DIST,%[WT%]DIST,%[WT%]DIST,%[WT%]DIST,%10Magnetic material68.122.4146.3153.9086.0318.4087.1815.3085.820.709.3 56.5686.54Non-magnetic31.885.9753.6918.7013.975.7812.825.4014.1814.5090.652.1813.4630Magnetic55.931.5321.9851.3092.5416.4095.1514.7088.394.6835.278.0782.58Non-magnetic44.076.89 78.025.257.461.064.852.4511.6110.9064.732.1617.4260Magnetic82.870.8519.7941.0092.3213.8093.0611.7091.592.3925.544.8672.54Nonmagnetic17.1316.6780.2116.507.684.986.945.2 08.4133.7074.468.9027.4690Magnetic59.810.568.6943.4085.5613.3083.0913.8079.862.2116.966.8968.39Nonmagnetic40.198.7691.3110.9014.444.0316.915.1820.1416.1083.044.7431.61

[0168] Looking at Table 7 above, at the 10-hour point, which is the initial stage of crushing, only a portion of the lithium compound of the shell coated on the NCM alloy part was crushed, and the recovery rate of the NCM alloy part recovered as a magnetic material was only at the level of 86% for Ni, 87% for Co, and 85% for Mn. However, when the pulverization time reaches 30 to 60 minutes, it can be confirmed that the recovery rate of Ni, Co, and Mn is recovered at 90% or more. In addition, when it exceeds 60 minutes and exceeds 90 minutes, the lithium compound is mostly pulverized and recovered at a high recovery rate of 91% in a non-magnetic manner, but the NCM alloy part, which is the core part, is continuously over-pulverized after the shell part is completely removed and rolled into a plate shape due to ductility, so that the plate-shaped particles are split again into fine particles, and there is a problem that the particles are excessively fine and the effect of the magnetic force on a single particle is minimal. Accordingly, the finely divided NCM alloy part cannot be recovered as a magnetic body even if it is magnetic during magnetic separation, and this results in a decrease again to 85% or less, which is the recovery rate of Ni, Co, and Mn.

[0169]

[0170] Although the preferred embodiments have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements made by those skilled in the art using the basic concepts defined in the following claims also fall within the scope of the present invention.

Claims

1. A step for preparing a product by reducing and heat-treating the recovered shredded material from a used battery at high temperature; A step of magnetically separating the heat-treated product into a first magnetic body and a first non-magnetic body; A step of crushing the first magnetic body and separating it into a second magnetic body and a second non-magnetic body; and A battery processing method comprising a step of floating and selecting the first non-magnetic substance.

2. In paragraph 1, The step of preparing a product by reducing and heat-treating the recovered waste from the above-mentioned waste battery at high temperature is as follows. Steps to prepare the battery; A step of crushing the above battery into battery waste; and A battery processing method comprising a step of heat treating the shredded battery waste at a temperature range of 600 to 1,500° C.

3. In paragraph 2, A battery processing method wherein the above heat treatment step is performed at an oxygen concentration of 0.1 to 2.0 vol%.

4. In paragraph 1, The above first magnetic body comprises a noble metal alloy including a noble metal, A method for processing a battery, wherein at least some of the above-mentioned valuable metal alloys have a core-shell structure in which a lithium compound is disposed on at least a portion of a surface of the above-mentioned valuable metal alloy.

5. In paragraph 1, A method for processing a battery, wherein the second non-magnetic body comprises at least one of a compound containing lithium and graphite.

6. In paragraph 1, The above magnetic separation step is a battery processing method in which the magnetic separation is performed in a magnetic strength range of 1,000 to 5,000 Gauss.

7. In paragraph 1, A battery processing method further comprising a step of further separating the first magnetic body into particles having a particle size of 50 to 70 ㎛.

8. In paragraph 1, A battery processing method, wherein the step of crushing a magnetic product among the magnetically separated products to separate a second magnetic body and a second non-magnetic body is performed at a shear force range of 1 to 5 m / sec.

9. In paragraph 1, A battery processing method, wherein the step of crushing a magnetic product among the magnetically separated products to separate a second magnetic body and a second non-magnetic body is performed for 20 to 80 minutes.

10. In paragraph 1, The step of separating magnetic and non-magnetic substances by crushing magnetic products among the magnetically separated products is as follows. A battery processing method, wherein the product having the above magnetic properties is crushed and then subjected to any one of particle size separation, flotation, and magnetic separation.

11. In Article 10, A battery processing method in which the above particle size separation is performed based on a particle size of 70 to 80 ㎛.

12. In paragraph 10, The above floating sorting step is a battery processing method for sorting a floating substance containing graphite and a sediment containing valuable metal.

13. In paragraph 11, The above sediment is magnetically separated to recover a material containing valuable metals, A battery processing method comprising crushing recovered materials together with the magnetic output.

14. In paragraph 1, After the step of separating magnetic and non-magnetic substances by crushing magnetic products among the magnetically separated products, Method for processing batteries comprising the step of drying the final product 15. In paragraph 14, A battery processing method wherein the step of drying the final product is performed at a temperature range of 80 to 200° C.

16. In paragraph 1, In the step of preparing a product by reducing and heat-treating the recovered waste from the above-mentioned waste battery at high temperature, At least some of the above outputs, A core portion comprising a valuable metal recovery alloy; and A battery processing method comprising a composition for recovering valuable metals, the composition comprising a shell portion disposed on the core portion and containing a lithium compound.

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