WO2025135426A1 - Method of disposal of waste batteries - Google Patents

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

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

As the demand for electric vehicles increases worldwide, the problem of disposal of waste batteries generated from said electric vehicles is emerging as a social issue. In the case of lithium secondary batteries, which are the main raw materials of said waste batteries, organic solvents, explosive substances, and heavy metals such as Ni, Co, Mn, and Fe are contained, but in the case of Ni, Co, Mn, and Li, they have high scarcity value as valuable metals, and the recovery and recycling process after the lithium secondary batteries are discarded is emerging as an important research field.

Specifically, a lithium secondary battery mainly consists of copper and aluminum used as a current collector, Li, Ni, Co, Mn-containing oxides constituting a cathode material, and graphite utilized as an anode material, and includes a separator separating the cathode material and the anode 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, LiPF ₆ is used.

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 valuable metals.

Recycling for the purpose of recovery of battery raw materials generally involves dismantling, discharging, crushing, heat treatment, recovery, and wet processes of batteries to recover valuable metals. In the case of the above discharge, salt water discharge is performed, and substances such as Na, K, Mg, Ca, and Cl that are introduced at this time are included as impurities in the recovered raw materials.

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

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 recover valuable metals, lithium oxide, and graphite by material from the black alloy to increase the recovery rate of valuable metals.

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.

According to one embodiment of the present invention, a battery processing method may include a step of preparing an output product by subjecting shredded materials recovered from a spent battery to high-temperature reduction and heat treatment, a step of magnetically separating the output 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 step of flotation and separation of the first non-magnetic body. In one embodiment, the step of preparing an output product by subjecting shredded materials recovered from a spent battery to high-temperature reduction and heat treatment may include a step of preparing a battery, a step of crushing the battery into battery shreds, and a step of heat-treating the crushed battery shreds in a temperature range of 600 to 1,500° C.

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

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

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

In one embodiment, the step of pulverizing the magnetic product among the magnetically separated products to separate the second magnetic body and the second non-magnetic body can be performed for 20 to 80 minutes. In one embodiment, the step of pulverizing the magnetic product among the magnetically separated products to separate the magnetic body and the non-magnetic body can be performed by any one of particle size separation, flotation, and magnetic separation after pulverizing the magnetic product.

In one embodiment, the particle size separation can be performed based on a particle size of 70 to 80 μm. In one embodiment, the flotation selection step can select a flotation material including graphite and a precipitate including valuable metal.

In one embodiment, the sediment may be magnetically separated to recover a material including a valuable metal, 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 the magnetic material and the non-magnetic material, the step of drying the final product may be included.

In one embodiment, the step of drying the final product can be performed at a temperature range of 80 to 200° C. In one embodiment, in the step of preparing an output product by reducing and heat-treating the recovered scrap from the spent battery at a high temperature, at least a portion of the output product can 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.

According to one embodiment of the present invention, a battery processing method includes a step of magnetically separating and crushing a product subjected to a 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.

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.

FIG. 2 is a flowchart of a battery processing method according to one embodiment of the present invention.

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

Figure 4 is a SEM photograph of a composition for recovering valuable metals.

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 only used to distinguish one part, component, region, layer, or section from another part, component, region, layer, or section. Thus, 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.

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

When a part is referred to as being "on" or "on" another part, it may be directly on or above the other part, or there may be other parts intervening. In contrast, when a part is referred to as being "directly on" another part, there are no other parts intervening.

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

Unless otherwise defined, all terms, including technical and scientific terms, used herein have the same meaning as commonly understood by those of ordinary skill in the art to which the present invention belongs. Terms defined in commonly used dictionaries are additionally interpreted as having a meaning consistent with the relevant technical literature and the presently disclosed content, and are not interpreted in an ideal or very formal sense unless defined.

Hereinafter, embodiments of the present invention will be described in detail. However, these are presented as examples, and the present invention is not limited thereby, and the present invention is defined only by the scope of the claims described below.

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.

Referring to FIGS. 1A to 1C, a recovered product from a waste battery according to an embodiment of the present invention 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 product. The recovered product from the waste battery may be a recovered product recovered by the battery processing method described later in FIG. 2. Specifically, the recovered product may be a valuable metal recovery alloy including a valuable metal, a lithium compound including lithium, and the remainder a graphite-based material.

In one embodiment, the recovered product may include 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 product. From the battery processing method described below, the valuable metal recovery alloy including the valuable metal, the lithium compound including lithium, and the graphite-based material including carbon can be recovered in powder form.

In one embodiment, the valuable metal recovery alloy may be from 20 to 35 wt% based on 100 wt% of the recovered material. Specifically, the valuable metal recovery alloy may be from 25 to 30 wt%. The valuable metal recovery alloy may be a material that includes a valuable metal such as Ni, Co, and Mn.

There is an advantage in that the recovery rate of valuable metals such as Ni, Co, and Mn can be increased by the weight % of the valuable metal recovery alloy in the recovered material satisfying the above-mentioned range. If it exceeds the upper limit of the above-mentioned range, the recovery rate of valuable metals can be increased, but there is an uneconomical problem. If it exceeds the lower limit of the above-mentioned range, there is a problem in that the recovery rate of valuable metals is reduced.

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

When the total amount of Ni, Co, and Mn in the valuable metal recovery alloy satisfies the above-mentioned range, the recovery rate of the 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 lack of economic feasibility or low recovery rate of the valuable metal.

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%.

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 (Ni ₃ C), 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.

In one embodiment, cobalt (Co) may be included in a range of 18 to 28 wt% based on 100 wt% of the total weight of the metal recovery alloy. Specifically, cobalt may be included in a range of 20 to 26 wt%.

When the content of the cobalt 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. When the content of the cobalt 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.

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%.

When the manganese content exceeds the upper limit of the above-mentioned range, there is a problem that the leaching rate due to the formation of manganese carbide is reduced. When the manganese content exceeds the lower limit of the above-mentioned range, there is a problem that the Mn recovery rate in leaching and solvent extraction is reduced.

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

There is an advantage in that the above lithium can maximize the Li recovery rate during the Li smelting process by satisfying the above range. If it exceeds the upper limit of the above range, there is a problem of reduced Ni and Co recovery rates, and if it exceeds the lower limit of the above range, there is a problem of increased process costs due to reduced Li recovery rates during the Li smelting process.

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%.

When 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 CuSO ₄ precipitation in leaching and solvent extraction, and when 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 materials 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.

In one embodiment, the metal recovery alloy may contain carbon (C) in a range of 0.1 to 10 wt%. When the carbon satisfies the range, 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%.

If the upper limit of the above range is exceeded, there is a problem that the anode material remains unreacted, alloying is not properly performed, and the metal oxide remains in the cathode material. If the lower limit of the above range is exceeded, there is a problem that lithium loss due to high temperature may occur.

In one embodiment, the metal recovery alloy may contain aluminum (Al) in a range of 0.25 to 30 wt %. If the content of the 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 the aluminum is outside the lower limit of the range, it is difficult to produce LiAlO ₂ , resulting in a problem of reduced Li recovery rates.

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.

By satisfying the above-mentioned range of the lithium compound, the recovery rate of lithium, which is one of the valuable metals, can be increased. If the lithium compound exceeds the lower limit of the above-mentioned range, this is because a lot of Li is lost to NCM alloy or graphite, which causes a problem of a decrease in the Li recovery rate, and when recovering Li in the downstream wet smelting process, there is a problem of an increase in the process cost because the Li content of the input raw material is reduced.

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

If the content of the lithium is outside the upper limit of the above-mentioned range, this means that lithium does not react with Al to form a lithium compound in the form of LiAlO ₂ , 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 content of the lithium is outside the lower limit of the above-mentioned range, this means that most of the lithium compounds were recovered in the form of LiAlO ₂ with low water solubility, which means that lithium compounds with high water solubility were dissolved in water during the selection process, which means that lithium must be recovered again from the water used in the selection process.

In one embodiment, the lithium compound may contain 20 to 30 wt% of aluminum (Al) based on 100 wt% of the lithium compound. Specifically, it may contain 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.

When the content of the above aluminum is outside the upper limit of the above range, there is a problem of increased cost of Ni, Co solvent extraction and crystallization process and decreased Ni, Co recovery rate due to excessive generation of Al ₂ (SO ₄ ) ₃ in the leaching and solvent extraction process. When the content of the above aluminum is outside the lower limit of the above range, there is a problem of poor generation of Li-Al-O oxide due to insufficient aluminum content.

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.

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 (Ni ₃ C), 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.

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 generated as a high-temperature reduction reaction is performed in a low-oxygen content range that reduces the generation of carbon dioxide. Since the graphite-based material satisfies the above-described range, the recycling yield of the graphite-based material that can be utilized as an anode material can be increased.

If the above graphite-based material exceeds the upper limit of the above-mentioned range, there is a problem that the content of graphite increases excessively, thereby lowering the recovery rate of valuable metals. If the above graphite-based material exceeds the lower limit of the above-mentioned range, there is a problem that the recovery rate of graphite is low.

In one embodiment, the graphite material may have a carbon (C) content of 80 to 90 wt% and may include the remainder of impurities. The carbon (C) content may be 83 to 87 wt%. When the carbon content satisfies the above-mentioned range, high-purity graphite including carbon can be obtained.

If the content of the carbon is outside the upper limit of the above-mentioned range, there is a problem that the recovery rate of the valuable metal is reduced. If the content of the carbon is outside the lower limit of the above-mentioned range, there is a problem that the recovery rate of the graphite is low.

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%. When the copper content is outside the upper limit of the above-mentioned range, there is a problem that the amount of acid used to remove Cu increases in the process of refining graphite into high-purity graphite.

FIG. 2 is a flowchart of a battery processing method according to one embodiment of the present invention.

Referring to FIG. 2, the battery processing method includes the steps of preparing an output product by subjecting shreds recovered from a spent battery to high-temperature reduction heat treatment, the step of magnetically separating the output product, and the step of crushing a magnetic output product among the magnetically separated output 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 an output product produced by subjecting shreds recovered from a spent battery to high-temperature reduction heat treatment. The valuable metal of the present invention may mean an expensive metal component included in a battery, and may mean nickel, cobalt, manganese, aluminum, copper, and lithium.

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, crushing the battery into battery shredded material, and high-temperature heat treatment of the crushed battery shredded material.

In the step of preparing the battery, the battery may be a method for processing various types of batteries including 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, specifically, a lithium secondary battery. More specifically, the battery has an advantage of being environmentally friendly by utilizing a waste battery.

In one embodiment, in the step of preparing a battery, the battery may include lithium (Li) and aluminum (Al). By coexisting lithium and aluminum in the battery, lithium and aluminum may be arranged as a physically and/or chemically bonded material in the resulting product after battery processing.

The step of crushing the battery may refer to a process of applying an impact or pressure to the battery so that a portion of the battery falls off from the battery. In one embodiment, the step of crushing the battery may refer to a process of crushing the battery, a process of cutting the battery, a process of compressing the battery, and a combination thereof. Specifically, the step of crushing may include any process that can destroy the battery to obtain small-sized fragments.

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 a tensile force, to destroy the battery. The step of crushing the battery may be performed, for example, using a crusher.

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.

In one embodiment, the step of crushing the battery comprises supplying conditions including an inert gas, carbon dioxide, nitrogen, water, or a combination thereof. Or, it can be carried out under vacuum atmosphere conditions of 100 torr or less. When carried out under the above-mentioned conditions, by suppressing the supply of oxygen, the electrolyte can be prevented from reacting with oxygen, thereby preventing an explosion caused thereby, and the vaporization of the electrolyte can be suppressed, so that flammable gases such as ethylene, propylene, or hydrogen are not generated.

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

In one embodiment, the step of high-temperature heat treatment of the battery shreds may be performed in a gas atmosphere of at least one of an inert gas, carbon dioxide, carbon monoxide, hydrocarbon gas, and oxygen. In the case of the inert gas, it may include, for example, at least one of argon and nitrogen. By performing a reduction reaction of the shreds in the gas atmosphere, there is an advantage in that the recovery rate of valuable metal elements contained in the battery shreds can be increased.

In one embodiment, the step of high-temperature heat treating the Ni, Co, Mn and Li containing battery scrap can be performed in a gas atmosphere including at least one of an inert gas, carbon dioxide, carbon monoxide, and hydrocarbon gas; and oxygen. In one embodiment, the gas atmosphere can be performed in a gas atmosphere having an oxygen concentration in a range of 0.1 to 2.0 vol%. Specifically, the gas atmosphere can be performed in a gas atmosphere having an oxygen concentration in a range of 0.4 to 1.2 vol%.

When the oxygen concentration exceeds the upper limit of the above-mentioned range, there is a problem that the reaction of Li ₂ O + C + O ₂ (g) = Li ₂ CO ₃ is promoted as the oxygen concentration increases, but at the same time, LiAlO ₂ and Li ₅ AlO ₄ 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 process and disappears by being gasified together with lithium, or that the production of Li ₂ CO ₃ (s) increases excessively, making it difficult to recover by acid leaching. When the oxygen concentration exceeds the lower limit of the above-mentioned range, there is a problem that the lithium recovery rate decreases.

In one embodiment, the step of high-temperature heat treating the battery shreds can be performed in a range of 600 to 1,500 °C. Specifically, the step of high-temperature heat treating can 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 treating the battery shreds, as the temperature increases, LiAlO ₂ (s) + 2Li ₂ CO ₃ (s) = Li ₅ AlO ₄ + 2CO ₂ (g) reaction generates Li ₅ AlO ₄ , but the LiF (g) vaporization reaction is promoted, so that when performed in the above-mentioned range, the yield of lithium can be improved.

If the upper limit of the above range is exceeded, there is a problem of lithium loss due to lithium vaporization. Specifically, if the upper limit of the above range is exceeded, there is a problem of lithium recovery rate being reduced due to lithium loss as the LiF(g) vaporization reaction is excessively promoted.

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 MnAl ₂ O ₄ is generated due to the reaction MnO(s)+2Al(s)+3/2O ₂ = MnAl ₂ O ₄ (s), which reduces the lithium concentration in the lithium compound, and there is a problem that the lithium recovery rate is lowered.

The step of magnetically separating the above-mentioned high-temperature heat-treated product can separate the first magnetic body having the magnetic force and the first non-magnetic body having the non-magnetism by magnetically separating the above-mentioned product. Magnetic separation can separate particles through contact with the magnetic body by utilizing the magnetic body, and various types of magnetic separation methods can be applied.

The above first magnetic body may be a composition including Ni, Co, and Mn, which are valuable metals, and specifically, a composition including 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 composition for valuable metal recovery may be recovered from a cathode material component in a spent battery.

The shell portion is arranged on the core portion and may include a lithium compound. Specifically, when recovering valuable metals from a waste battery, the valuable metals in the waste 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, thereby performing the function of agglomerating the reduced valuable metals. The copper current collector and the aluminum current collector may perform a partial reduction reaction with the positive electrode oxide and the remainder may react with lithium, so that a compound in the form of an oxide containing lithium may remain. A detailed description thereof will be described later with reference to FIGS. 3A and 3B and FIG. 4.

The second non-magnetic material may include at least one of a compound including Li that is not combined with a valuable metal in the magnetic separation step and a graphite material including carbon.

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

Since the magnetic separation step is performed within the above magnetic strength range, there is an advantage in that valuable metals can be separated efficiently. If the magnetic strength range exceeds the upper limit of the above-mentioned range, even a trace amount of valuable metal is recovered, so the recovery rate increases, but the grade of the recovered valuable metal is lowered and the amount of impurities such as graphite and copper increases, so there is a problem that the process efficiency in the next process, the wet smelting process, is lowered and the processing cost increases. If the magnetic strength range exceeds the lower limit of the above-mentioned range, there is a problem that the recovery rate of valuable metals is lowered, so that the loss of Ni, Co, and Mn increases.

The step of separating a magnetic body and a non-magnetic body by crushing a magnetic product among the magnetically separated products may be a step of crushing a magnetically selected first magnetic body. The first magnetic body means a core part including a valuable metal alloy and a compound including lithium disposed on the core part, as described above. The core part and the shell part may be separated from the first magnetic body through a crushing process. Specifically, the first magnetic body may be separated into a second magnetic body and a second non-magnetic body through the crushing process described above. The second magnetic body means, for example, an NCM alloy including Ni, Co, and Mn, and the second non-magnetic body may be a compound including lithium, for example, lithium aluminate (LiAlO ₂ ).

In one embodiment, the first magnetic body can be separated into the valuable metal recovery alloy and the lithium-containing compound by a 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 also the lithium compound can be separated at the same time, so that the lithium recovery rate is high and the amount of lithium lost can be reduced.

In one embodiment, the pulverizing step uses equipment that pulverizes using a shear force in the form of a vertical attrition mill, and the RPM of the attrition mill 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 pulverizing step can be performed in a shear force range of 2 to 3 m/sec based on the Tip Speed. Since the pulverizing 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.

At this time, Tip Speed can be obtained by the following formula: Tip Speed = Pi × Impeller Diameter × RPM/100

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

In one embodiment, the crushing step can be performed for 20 to 80 minutes. Specifically, the crushing step can be performed for 30 to 60 minutes. As the crushing step is performed within the above-described range, the recovery rate of valuable metals such as Ni, Co, Mn, and Li can be increased.

In the above-mentioned crushing step, if the upper limit of the above-mentioned range is exceeded, the magnetic body including the core part's magnetic body and the lithium compound of the shell part is excessively crushed, and rolling is performed into a plate shape due to ductility, and the plate-shaped particles are continuously over-pulverized and split again into fine particles, so that the effect of the magnetic force is insufficient in additional 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 body of the core-shell structure.

In one embodiment, after the pulverizing step, a step of further separating 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 the difference in specific gravity of each material, and for example, the particles may be separated based on the size of the specific gravity of the particles corresponding to the specific solvent by utilizing a specific solvent.

When the first magnetic body is separated from the core and shell through the above-described pulverizing step, the valuable metal alloy is separated into particles that are elongated due to the ductile nature of the metal and have a large particle size, and the compound containing lithium 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 ㎛ and a valuable metal alloy having a particle size of 70 to 80 ㎛ or more.

In one embodiment, the core and shell portions separated through the above-described pulverizing 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.

In another embodiment, the core and shell portions separated through the above-described crushing step may be subjected to magnetic separation. Through the magnetic separation, a valuable metal alloy including Co having magnetism and a compound including lithium having no magnetism can be easily separated.

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

In one embodiment, the step of separating the first non-magnetic body may include separating the first non-magnetic body having a non-magnetism separated in the first magnetic separation step, which includes graphite.

In one embodiment, the flotation step may be a step of selecting a flotation material including graphite and a precipitate including valuable metal. Specifically, the flotation step may be a step of floatation of hydrophobic graphite in the first non-magnetic body and precipitation and separation of a compound including lithium and a particulate valuable metal alloy.

In one embodiment, a step of magnetically separating the sediment to recover a material including a valuable metal and crushing the recovered material together with the magnetic output may be performed. A detailed description of the crushing step is as described above.

In one embodiment, the step of pulverizing a magnetic product among the magnetically separated products to separate magnetic substances and non-magnetic substances may include a step of drying the final product. Through the drying step, the valuable metal alloy, the compound including lithium, and the graphite may be dried in a powder form.

In one embodiment, the step of drying the final product can be performed at a temperature in the range of 80 to 200° C. Specifically, the step of drying the final product can be performed at a temperature in the range of 100 to 150° C.

If drying is performed outside the upper limit of the above temperature range, there is a problem that combustible materials such as graphite are burned. If drying is performed outside the lower limit of the above temperature range, there is a problem that the moisture in the powder-state particles, which are the final product, is not completely dried and a product with a high moisture content is discharged, which increases the amount of acid used in the leaching process of the downstream wet refining process.

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

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 a high temperature does not form an alloy by being reduced, such as Ni, Co, and Mn, but combines with the Al component in the battery to form a compound containing lithium, for example, lithium oxide. It can be confirmed that the lithium oxide is formed as, for example, LiAlO ₂ , Li ₅ AlO ₄ , and Li ₂ CO ₃ . In one embodiment, the composition for recovering valuable metals may further include LiF. The LiF may be a result of the remaining amount of electrolyte depending on the degree of pretreatment.

In one embodiment, LiAlO ₂ 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°. Li ₅ AlO ₄ can include XRD peaks of at least one of 19.5 to 20.2° and 21.6 to 22.2°.

The LiAl ₅ O ₈ composition can include XRD peaks of at least one of 15.0 to 17.4°, 24.2 to 26.1°, 31.4 to 33.1, 36.2 to 40.3, 46.1 to 47.3, 61.1 to 63.4, and 66.2 to 68.7. The LiF composition can include XRD peaks of at least one of 37.5 to 40.2°, 43.9 to 46.5°, and 64.5 to 66.5°.

The Li ₃ PO ₄ composition can include XRD peaks of at least one of 29.2 to 40.1° and 52 to 77.1°. The Li ₂ SiO ₃ composition can include XRD peaks of at least one of 17.7 to 20.1°, 26.1 to 29.5°, 32.2 to 36.2, and 37.6 to 39.7. The Li ₄ SiO ₄ composition can include XRD peaks of at least one of 16.2 to 18.3°, 21.4 to 25.2°, 34.2 to 39.7, and 59.2 to 63.4.

The Li ₂ Si ₂ O ₅ composition can include XRD peaks of at least one of 16.2 to 18.3°, 21.4 to 25.2°, 34.2 to 39.7, and 59.2 to 63.4°. The Li ₂ CO ₃ composition can include XRD peaks of at least one of 24.0 to 26.0°, 27.0 to 29.0°, 34.0 to 36.0°, and 37.0 to 39.0°.

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

Referring to FIG. 4, the 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 mean an expensive metal component included in a battery, and may mean nickel, cobalt, manganese, aluminum, copper, and lithium. The core portion of the composition for recovering valuable metals may be recovered from a cathode component in a spent battery.

The shell portion is arranged on the core portion and may include a lithium compound. Specifically, when recovering valuable metals from a waste battery, the valuable metals in the waste 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, thereby performing the function of agglomerating the reduced valuable metals. The copper current collector and the aluminum current collector may perform a partial reduction reaction with the positive electrode oxide and the remainder may react with lithium, so that a compound in the form of an oxide containing lithium may remain.

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 100 wt% of the total. When the content of Li in the lithium compound satisfies the above-mentioned range, 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 a large amount of compounds that are difficult to recover due to water-solubility problems are generated as the Li ₂ O content increases, thereby lowering the lithium recovery rate, 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 low.

In one embodiment, the lithium compound can include at least one of LiAlO ₂ , Li ₅ AlO ₄ , LiAl ₅ O ₈ , Li ₂ CO ₃ , LiF, Li ₃ PO ₄ , Li ₂ SiO ₃ , Li ₄ SiO ₄ , and Li ₂ Si ₂ O ₅ . In one embodiment, the lithium compound can include lithium aluminum oxide.

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.

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

If the content of the lithium aluminum oxide exceeds the upper limit of the above-mentioned range, there is a problem that highly water-soluble lithium hydroxide, lithium carbonate, lithium fluoride, etc. dissolve in large quantities in water during the sorting process. If the content of the lithium aluminum oxide exceeds the lower limit of the above-mentioned range, it means that most of the lithium compounds are recovered in the form of LiAlO ₂ with low water solubility, which means that highly water-soluble lithium compounds dissolve in water during the sorting process, and this causes a problem that lithium must be recovered again from the water used during the sorting process.

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 include 2 to 30 wt% based on 100 wt% of the valuable metal recovery composition. Specifically, it may include 10 to 25 wt%. Since the lithium and silicon-containing oxide satisfy the above-mentioned range, there is an advantage in that a stable product can be secured under a high temperature and an appropriate oxygen concentration atmosphere, thereby increasing the real yield of lithium during acid leaching.

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 the energy cost increases 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 insufficient 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.

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

If the content of the above silicon (Si) 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 smelting process. If the content of the above silicon (Si) exceeds the lower limit of the above-mentioned range, there is a problem that the remaining weight % of the silicon of 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 the graphite and lithium compounds.

In one embodiment, Li ₂ CO ₃ may be included in an amount of 30% or less based on 100 wt% of the entire composition. The Li ₂ CO ₃ may be included in an amount of 15.0% or less, more specifically, 5% or less. When the content of the Li ₂ CO ₃ satisfies the above-described range, there is an advantage of preventing the production of a large amount of a compound that is difficult to recover due to water-solubility problems.

In one embodiment, LiF may be included in an amount of 30 wt% or less based on 100 wt% of the entire 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 entire composition. By satisfying the above-mentioned range of the content of LiF, there is an advantage of preventing a large amount of a compound that is difficult to recover due to a water-solubility problem.

If the LiF exceeds the upper limit of the above-mentioned range, there is a problem that the pH control is difficult 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 above-mentioned range, there may be a problem that the leaching process time is delayed because Li ₂ SiO ₃ , Li ₄ SiO ₄ , and Li ₂ Si ₂ O _{5 ,} etc. increase, making sulfuric acid leaching difficult.

In one embodiment, the total content of Li ₂ CO ₃ 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.

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 problems 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 Li ₂ SiO ₃ , Li ₄ SiO ₄ , and Li ₂ Si ₂ O ₅ increase, making sulfuric acid leaching difficult, which causes a problem in that the leaching process time is delayed.

By ensuring that the combined amount of Li ₂ CO ₃ and LiF satisfies the above-mentioned range, it is possible to prevent the production of a large amount of compounds that are difficult to recover due to water solubility problems, and to appropriately adjust the high temperature and oxygen concentration to produce a large amount of stable compounds with excellent leaching rates in sulfuric acid, thereby increasing the efficiency of lithium recovery.

In one embodiment, Li ₃ PO ₄ may be included at 10 wt% or less, based on 100 wt% of the entire composition. The Li ₃ PO ₄ may be included at 5 wt%, specifically, 3 wt% or less, and more specifically, 0.1 to 0.7 _wt %, based on 100 wt% of the entire composition. By satisfying the above-described range, the _Li recovery rate can be prevented from being lowered due to problems such as the leaching behavior depending on the pH change due to the PO ^3- _anion during acid leaching and the generation of _LiOH during impurity removal. By satisfying the above-described range, the Li recovery rate can be prevented from being lowered due to problems such as the leaching behavior depending on the pH change due to the PO ^3- anion during acid leaching and the generation of LiOH during impurity removal.

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

<Experimental Example> - Control of waste battery conditions

The battery shredder can be shredded through the shredding step so that the longest length in width and length is 100 mm or less. Specifically, the optimal size of the battery shredder can be 10 to 40 mm in the longest length in width and length. This is to prevent a fire from occurring when shredding the battery.

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

<Experimental Example 1>

1. Step of preparing a composition for recovering valuable metals

A cell, module, or pack, which is a spent electric vehicle battery, is prepared, which includes a positive electrode material containing lithium ions, an anode material 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 device under atmospheric or inert gas conditions so that the longest length or width becomes 100 mm or less.

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

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

The components and contents in Table 1 below were measured by quantitative analysis using (ICP-OES) equipment and C/S analysis equipment.

Li(wt%) Ni(wt%) Co(wt%) Mn(wt%) Al(wt%) Cu(wt%) C(wt%) note Experimental Example 1 3.91 19.85 6.13 6.56 7.20 11.43 33.70 Example

2. The composition for recovering precious metals that had undergone a high-temperature reduction process in the first magnetic separation step was separated into magnetic and non-magnetic substances using a magnetic separator having a magnetic strength of 3000 Gauss.

Experimental Example 2_1 in Table 2 below shows the components and contents of magnetic and non-magnetic substances separated by passing through a 3000 Gauss magnetic separator.

magnetism
Whether gun
Content
(wt%) Li(wt%) Ni(wt%) Co(wt%) Mn(wt%) Al(wt%) Cu(wt%) C(wt%) note Experimental Example 2_1 magnetism 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

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 high contents 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.

3_1. Floating selection stage

As in Experimental Example 2_2, the non-magnetic material separated through magnetic separation was 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 of kerosene, and 0.1 ml/100 g of MIBC.

Through the above flotation, light graphite powder floats to the top of the equipment and is separated to recover graphite.

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

Sedimentation
Whether gun
Content
(wt%) Li(wt%) Ni(wt%) Co(wt%) Mn(wt%) Al(wt%) Cu(wt%) C(wt%) note Experimental Example 3_1 Floating (O/F) 81.11 0.44 0.33 0.17 0.12 0.48 1.25 91.32 Example Experimental Example 3_2 Sedimentation (U/F) 18.89 1.06 1.04 0.37 1.09 10.01 18.04 5.75 Example

Looking at Table 3 above, the C content of the material floating in Over Flow (O/F) was 92.5%, which is a significant increase compared to the C content of 35.07% in the initial battery shreds and the C content of 75.30% in the raw material separated into non-magnetic substances through magnetic separation and fed into the flotation separator. In addition, the C content of the sediment remaining in Under Flow (U/F) was 5.75%, and it can be seen that most of the hydrophobic C was recovered as floating matter. In addition, looking at the lithium content ratio of the floating matter and sediment, it can be seen that most of the lithium did not float but remained in the sediment, so that C and lithium could be efficiently separated through flotation. In addition, judging from the high aluminum content of the sediment, it is judged that most of the lithium remained in the sediment in the form of LiAlO _2. 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

2. The magnetic material that has gone through the magnetic separation step is pulverized using Attrition Mill equipment, 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 composed of a core part including a valuable metal and a shell part including a compound including lithium arranged on the core part, and it was confirmed that the core part and the shell part are separated during the pulverization process of the composition for recovering valuable metal.

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.

magnetism gun
Content
(wt%) Li(wt%) Ni(wt%) Co(wt%) Mn(wt%) Al(wt%) Cu(wt%) note Experimental Example 4_1 magnetism 67.97 0.37 42.19 12.94 13.51 2.15 3.79 Example Experimental Example 4_2 Non-magnetic 32.03 14.56 1.15 1.40 1.21 17.96 27.45 Example

Looking at Table 5 above, in order to separate the alloy core part containing valuable metals and the lithium compound from the resultant product after the pulverization 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 part containing valuable metals, Experimental Example 4_1, contained an excessive amount of Ni, Co, and Mn. Experimental Example 4_2, separated as a non-magnetic material, was the result of the shell part containing lithium being pulverized, and it was confirmed that it had a high lithium content. In the product recovered as a by-product in the magnetic separation, the shell part in the form of oxides is pulverized during the pulverization process, and the core part, which has ductility, is continuously pulverized inside the pulverizer and rolled into a plate shape, causing the particle size to increase and the thickness to decrease rather than the initial particle size. In contrast, since the shell part is brittle in the form of oxides, the pulverization continues as the pulverization time increases, causing the particle size to decrease. 5. Secondary separation stage

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

6. Drying stage

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

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

Main components gun
Content
(wt%) Li(wt%) Ni(wt%) Co(wt%) Mn(wt%) Al(wt%) Cu(wt%) C(wt%) note Valuable metal alloy 48.35 0.37 42.19 12.94 13.51 2.15 3.79 7.16 Experimental Example 4_1 lithium compounds 24.95 9.55 1.11 1.02 1.17 15.04 23.96 12.70 Experimental example 4_2 and Experimental example 3_2 black smoke 26.69 0.44 0.33 0.17 0.12 0.48 1.25 91.32 Experimental Example 3_1

Looking at Table 5 above, the valuable metal alloy containing Ni, Co, and Mn as main components can be recovered from the magnetic body separated through the magnetic separation, pulverization, and magnetic separation steps, as in Experimental Example 4_1. The lithium compound contains lithium as a main component and can be recovered from the sum of the non-magnetic body separated through the 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, by going through the battery processing method described above, it was confirmed that 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 utilized as an anode material can be increased by separating graphite separately. <Experimental Example 2>: Changes in the composition of magnetic and non-magnetic materials according to changes in magnetic strength

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.

magnetism
century
[G] division Weight
[wt%] Li Ni Co Mn Al Cu [WT%] DIST
,% [WT%] DIST
,% [WT%] DIST
,% [WT%] DIST
,% [WT%] DIST
,% [WT%] DIST
,% 500 Magnet 7.23 2.66 35.93 46.40 29.85 16.00 36.61 13.30 38.17 5.65 44.93 4.90 6.98 Non-magnetic 92.77 1.50 64.07 8.50 70.15 2.16 63.39 1.68 61.83 0.54 55.07 5.09 93.02 1000 Magnet 32.53 2.92 60.30 38.40 87.85 13.30 91.18 11.10 86.16 6.46 33.26 8.38 46.49 Non-magnetic 67.47 2.51 39.70 2.56 12.15 0.62 8.82 0.86 13.84 6.25 66.74 4.65 53.51 2000 Magnet 36.11 3.09 59.66 36.80 96.12 12.40 97.63 10.70 94.09 7.24 75.33 5.94 47.04 Non-magnetic 63.89 1.15 40.34 0.84 3.88 0.17 2.37 0.38 5.91 1.34 24.67 3.78 52.96 3000 Magnet 36.19 3.26 42.98 33.40 92.48 11.20 95.6. 9.54 91.54 7.20 84.66 6.01 48.98 Non-magnetic 63.81 1.25 57.02 1.54 7.52 0.29 4.37 0.50 8.46 0.74 15.34 3.55 51.02 5000 Magnet 35.61 3.08 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

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), where the magnetic strength is weak, the 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, it can be confirmed that most NCM cathode materials are recovered as magnetic materials at 2000 Gauss or higher.

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

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

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), pulverization container size 1 L, solid content concentration 30%, pulverization time 0 to 90 minutes, and magnetic and non-magnetic bodies were analyzed according to pulverization time.

Grinding time
[minute] division Weight
[wt%] Li Ni Co Mn Al Cu [WT%] DIST
,% [WT%] DIST
,% [WT%] DIST
,% [WT%] DIST
,% [WT%] DIST
,% [WT%] DIST
,% 10 Magnet 68.12 2.41 46.31 53.90 86.03 18.40 87.18 15.30 85.82 0.70 9.35 6.56 86.54 Non-magnetic 31.88 5.97 53.69 18.70 13.97 5.78 12.82 5.40 14.18 14.50 90.65 2.18 13.46 30 Magnet 55.93 1.53 21.98 51.30 92.54 16.40 95.15 14.70 88.39 4.68 35.27 8.07 82.58 Non-magnetic 44.07 6.89 78.02 5.25 7.46 1.06 4.85 2.45 11.61 10.90 64.73 2.16 17.42 60 Magnet 82.87 0.85 19.79 41.00 92.32 13.80 93.06 11.70 91.59 2.39 25.54 4.86 72.54 Non-magnetic 17.13 16.67 80.21 16.50 7.68 4.98 6.94 5.20 8.41 33.70 74.46 8.90 27.46 90 Magnet 59.81 0.56 8.69 43.40 85.56 13.30 83.09 13.80 79.86 2.21 16.96 6.89 68.39 Non-magnetic 40.19 8.76 91.31 10.90 14.44 4.03 16.91 5.18 20.14 16.10 83.04 4.74 31.61

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 levels of Ni 86%, Co 87%, and Mn 85%. 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% non-magnetically, 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, and the plate-shaped particles are split again into fine particles due to continuous over-pulverization, and there is a problem that the particles are excessively fine and the influence 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.

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 (16)

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. In the first paragraph, 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. In the second paragraph, A battery processing method wherein the above heat treatment step is performed at an oxygen concentration of 0.1 to 2.0 vol%. In the first paragraph, 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. In the first paragraph, A method for processing a battery, wherein the second non-magnetic body comprises at least one of a compound containing lithium and graphite. In the first paragraph, 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. In the first paragraph, 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 ㎛. In the first paragraph, 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. In the first paragraph, 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. In the first paragraph, 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. 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 ㎛. In Article 10, The above floating sorting step is a battery processing method for sorting a floating substance containing graphite and a sediment containing valuable metal. In Article 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. In the first paragraph, 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 In Article 14, A battery processing method wherein the step of drying the final product is performed at a temperature range of 80 to 200° C. In the first paragraph, 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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