Methods for disposing of waste batteries

Abstract

The waste battery treatment method according to the present invention includes a discharging step of discharging a waste battery, a disassembling step of disassembling the discharged waste battery into cell units, a crushing step of crushing the disassembled waste battery, a roasting step of roasting the waste battery crushed into cell units, a pulverizing step of pulverizing the roasted waste battery, and a wet process of extracting and recovering metals from the pulverized waste battery.

Description

Technical Field

[0001] The present invention relates to a method for treating waste batteries, and more particularly, to a method for recovering metal in compound form from batteries in the form of a Pack whose life has ended.

Background Art

[0002] Recently, due to the spread of the Battery Electric Vehicle (BEV) market, the demand for secondary batteries has been increasing. Secondary batteries cannot be used permanently and have a specific expiration date. End-of-life secondary batteries can be discarded, reused, or recycled, and recently, research has been continuously conducted to recover rare metals, which are useful resources in the batteries, through the recycling of secondary batteries.

[0003] Conventionally, since the development of treatment technologies for waste batteries mainly in the form of small batteries has been promoted, the development of elemental technologies has been carried out rather than integrated process technologies. However, most of the recently increasing battery demand is for medium and large-sized batteries in the form of packs used as power sources for electric vehicles, so waste battery treatment technologies for medium and large-sized batteries are required. Also, rather than the development of existing elemental technologies separately, the development of an integrated recycling technology from the complete form of the battery to the final target metal compound is required.

Summary of the Invention

Problems to be Solved by the Invention

[0004] An object of the present invention is to provide a method for treating waste batteries that can efficiently recover metals in the battery in compound form through a discharging process, a disassembling process, a crushing process, a roasting process, a pulverizing process, and a wet process from batteries in the form of a Pack whose life has ended.

Means for Solving the Problems

[0005] A waste battery processing method according to one embodiment of the present invention includes a discharge step of discharging a waste battery; a disassembly step of disassembling the discharged waste battery into cell units; a crushing step of crushing the waste battery disassembled into cell units; a roasting step of roasting the crushed waste battery; a crushing step of pulverizing the roasted waste battery; and a wet step of extracting and recovering metal from the crushed waste battery.

[0006] The aforementioned waste batteries may be battery packs that have reached the end of their lifespan.

[0007] The waste battery processing method according to the present invention allows the waste battery to be discharged through the discharge step so that the voltage of the waste battery becomes 30V or less.

[0008] The waste battery processing method according to the present invention can crush batteries into cell units of 20 cm or less through the crushing step.

[0009] The waste battery processing method according to the present invention may omit the step of separating black mass from the crushed waste batteries.

[0010] In the waste battery processing method of the present invention, the discharge step, the dismantling step, the crushing step, the roasting step, and the pulverization step can be carried out continuously by automated equipment.

[0011] In the waste battery processing method of the present invention, the discharge step, the dismantling step, and the crushing step can be performed by automated equipment using a robot.

[0012] In the waste battery treatment method of the present invention, metal compounds can be recovered through the wet process.

[0013] The aforementioned metal compound may include at least one selected from the group consisting of lithium hydroxide, lithium carbonate, and lithium phosphate.

[0014] The aforementioned metal compound may include one sulfate selected from the group consisting of nickel, cobalt, and manganese.

[0015] The aforementioned metal compound may include a nickel-cobalt-manganese compound in solution. [Effects of the Invention]

[0016] According to the present invention, by disassembling discharged waste batteries into individual cells and then performing a wet process, the time required to recover metals in compound form from the batteries can be shortened, and by-products generated during the process can be reduced, thereby increasing the metal recovery rate.

[0017] In particular, the present invention minimizes the loss rate of metal components present in battery packs because, after crushing / grinding individual cells, the metal is immediately recovered through a wet process without a separate process for separating black mass.

[0018] Furthermore, the present invention dramatically reduces the time required to recover compound metals from battery packs by automating the discharge, dismantling, crushing, roasting, and pulverization processes, excluding the wet process. [Brief explanation of the drawing]

[0019] [Figure 1] Figure 1 is a complete step-by-step diagram of the waste battery processing method according to the present invention. [Figure 2] Figure 2 is an overall process diagram showing the detailed steps of the waste battery processing method according to the present invention. [Modes for carrying out the invention]

[0020] The waste battery processing method according to the present invention includes a discharge step of discharging the waste battery, a disassembly step of disassembling the discharged waste battery into cell units, a crushing step of crushing the waste battery disassembled into cell units, a roasting step of roasting the crushed waste battery, a crushing step of pulverizing the roasted waste battery, and a wet step of extracting and recovering metal from the crushed waste battery.

[0021] Hereinafter, the present invention will be described while referring to the drawings. FIG. 1 is an overall process diagram of the waste battery treatment method according to the present invention. As shown in FIG. 1, the waste battery treatment method according to an embodiment of the present invention may include a discharging process (S100), a disassembling process (S200), a crushing process (S300), a roasting process (S400), a pulverizing process (S500), and a wet process (S600).

[0022] Discharge process (S100) The discharging process (S100) is a process of discharging the electric power stored in the waste battery in order to prevent an explosion of the waste battery that may occur during subsequent processes. For example, in the discharging process (S100), the waste battery may be connected to a discharger and discharged so that the voltage of the waste battery becomes 30 V or less, preferably 0.2 V or less. By discharging the waste battery to the voltage within the above numerical range through the discharging process (S100), an explosion of the waste battery in the subsequent disassembling process (S200) can be prevented, and stability can be ensured.

[0023] The waste battery treatment method according to the present invention can be performed on medium and large-sized batteries used in electric vehicles. In this case, the waste battery to be discharged through the discharging process (S100) may be a battery in the form of a pack whose life has ended.

[0024] The discharging process (S100) can be performed through mechanical discharging using a discharger, or brine discharging using brine. Preferably, the discharging process (S100) can be performed through mechanical discharging. When mechanical discharging is used, stability against fire and explosion can be ensured, the discharging state can be confirmed, and the discharging time required and the expenditure of incidental costs can be reduced.

[0025] Demolition process (S200) The disassembling process (S200) is a process of further disassembling the waste battery in the form of a pack into smaller units. The disassembling process (S200) according to the present invention disassembles the waste battery in the form of a pack into cells. For example, the disassembling process (S200) can disassemble the waste battery in the form of a pack into modules and then into cells.

[0026] While directly recycling battery packs offers convenience, the inclusion of the Battery Management System (BMS) and various control devices along with the battery leads to an increased influx of impurities. Therefore, to recycle batteries, they must be disassembled at least to the module level. The present invention is characterized by disassembling battery packs not to the module level, but to the cell level. Compared to disassembling battery packs to the module level, the present invention significantly reduces the amount of impurities (e.g., Al and Fe) in the recovered metallic material by disassembling the battery packs to the cell level. Furthermore, because the amount of aluminum in the recovered metallic material is significantly reduced, there is an advantage in minimizing the need for separate processes to remove aluminum during the recovery of the metallic material.

[0027] On the other hand, when dismantling a pack of waste batteries down to the module level, the dry process (roasting process) is carried out at a minimum high temperature of 1200°C, which causes manganese (Mn) to be discharged as manganese oxide (MnO) slag, making manganese recovery impossible, and lithium volatilizes in a gaseous state, potentially reducing the lithium recovery rate. However, when dismantling a pack of waste batteries down to the cell level, as in the present invention, the temperature in the dry process can be relatively lowered, so unlike when dismantling a pack of waste batteries down to the module level, manganese can be recovered, and the lithium (Li) recovery rate can be significantly higher compared to when dismantling down to the module level.

[0028] In one embodiment, as shown in Figure 1, the dismantling process (S200) may be performed after the discharge process (S100). However, the present invention is not limited to this, and in other embodiments, unlike in Figure 1, the dismantling process (S200) may be performed first, followed by the discharge process (S100).

[0029] Crushing process (S300) The crushing step (S300) is a process of crushing the waste batteries that have been disassembled into individual cells. The crushing step (S300) can crush the individual battery cells to a size of 20 cm or less, specifically 15 cm or less, and more specifically 10 cm or less. By crushing the batteries to the size within the above numerical range through the crushing step (S300), the crushed batteries can be reductively roasted more uniformly in the roasting step (S400).

[0030] The crushing process (S300) may be carried out under a nitrogen (N2) atmosphere while spraying water to prevent sparks and explosions. After crushing, the sprayed water and electrolytes that have flowed out of the waste batteries may be removed. For example, the water and electrolytes may be removed by centrifugal force through a rotary barrel.

[0031] The crushing step (S300) may include a drying step (not shown) for drying the crushed batteries.

[0032] According to the present invention, the aforementioned discharge process (S100), dismantling process (S200), and crushing process (S300) can be performed by automated equipment using a robot, thereby significantly reducing the time required to recover metal from waste batteries.

[0033] Roasting process (S400) The roasting process (S400) is a process for dry processing of the crushed battery. Specifically, the roasting process (S400) may be an inert atmospheric roasting (IAR) process in which the crushed battery is reduced in an inert atmospheric roasting atmosphere. For example, in the roasting process (S400), the battery, which has been crushed to a size of 5 cm to 10 cm, can be reduced in an atmosphere of nitrogen (N2) at a temperature of 800°C to 900°C for 1 to 3 hours. By roasting the crushed battery in an inert atmospheric roasting atmosphere, lithium (Li) can be converted into the form of Li2CO3, which can be dissolved in water. In the process of reducing the crushed battery for lithium separation, some high oxides (Me2O3, Me=Ni, Co, Mn) are reduced to low oxides (MeO, Me=Ni, Co, Mn), and the amount of auxiliary raw materials (H2O2, hydrogen peroxide) added during sulfuric acid leaching can be reduced.

[0034] Grinding process (S500) The grinding process (S500) is a process of grinding the batteries that have been dry-treated through the roasting process (S400). For example, in the grinding process (S500), batteries that have been reductively roasted through a ball mill can be classified into 200 mesh or less and 80% or more.

[0035] The grinding process (S500) may be carried out under a nitrogen (N2) atmosphere while spraying water to prevent sparks and explosions. After grinding, the sprayed water and electrolytes that have flowed out of the waste battery may be removed. For example, the water and electrolytes may be removed by centrifugal force through a rotary barrel.

[0036] In the waste battery processing method according to the present invention, a separate step of separating black mass after crushing / grinding the battery cells is omitted. Since the present invention recovers metals immediately through a wet process without a separate step of separating black mass, the loss rate of metal components present in the battery pack can be minimized.

[0037] The discharge process (S100), dismantling process (S200), crushing process (S300), roasting process (S400), and pulverization process (S500) according to the present invention can be carried out continuously by automated equipment. Therefore, it is possible to realize an integrated recycling process technology from waste batteries in pack form to the final target metal compounds, and the time required to recover metals from waste batteries can be significantly reduced.

[0038] Wet process (S600) The wet process (S600) is a process for recovering metallic material using pulverized batteries. The metal recovered through the wet process (S600) may be in compound form. For example, the wet process (S600) can recover metallic material in compound form from pulverized batteries after the pulverization process (S500).

[0039] The metal compound recovered through the wet process (S600) may include at least one selected from the group consisting of lithium hydroxide, lithium carbonate, and lithium phosphate. Through the wet process (S600) of the present invention, it is possible to produce high-purity lithium carbonate (Li2CO3) and high-purity lithium hydroxide (LiOH·H2O) with excellent lithium recovery rates. Lithium hydroxide can be produced through the following steps: pre-separation process (S610), weak acid leaching process (S612), post-separation process (S614), lithium phosphate production process (S616), lithium sulfate solution production process (S618), lithium carbonate production process (S620), lithium hydroxide solution production process (S622), and ion exchange resin process (S624), as described below.

[0040] Furthermore, the metal compounds recovered through the wet process (S600) may include copper(II) sulfide (CuS).

[0041] In one embodiment of the present invention, the metal compound recovered through the wet process (S600) may include one sulfate selected from the group consisting of nickel, cobalt, and manganese. In another embodiment of the present invention, the metal compound recovered through the wet process (S600) may include a nickel-cobalt-manganese compound in solution, for example, an NCM (Ni, Co, Mn) solution.

[0042] Nickel sulfate can be produced as described below through a pre-separation step (S610), a weak acid leaching step (S612), a post-separation step (S614), a two-stage leaching step (S626), a first solvent extraction step (S628), and a first impurity removal step (S630).

[0043] Cobalt sulfate can be produced as described below through a pre-separation step (S610), a weak acid leaching step (S612), a post-separation step (S614), a two-stage leaching step (S626), a first solvent extraction step (S628), a second solvent extraction step (S632), and a second impurity removal step (S634).

[0044] Manganese sulfate can be produced as described below through a pre-separation step (S610), a weak acid leaching step (S612), a post-separation step (S614), a two-stage leaching step (S626), a first solvent extraction step (S628), a second solvent extraction step (S632), and a third impurity removal step (S636).

[0045] The following describes each step of the wet process (S600) in more detail with reference to Figure 2. Figure 2 is a process diagram of the wet process (S600) in the waste battery processing method according to the present invention.

[0046] Preliminary separation process (S610) The pre-separation step (S610) is a process in which water is added to the pulverized battery after roasting to separate lithium (Li) by leaching. For example, in the pre-separation step (S610), the pulverized battery after the pulverization step (S500) can be dissolved in water, and the lithium (Li) solution can be leached at 10°C to 30°C for 1 to 3 hours to produce a lithium carbonate (Li2CO3) solution, and the cake can be separated. Through the pre-separation step (S610), the operating costs and auxiliary material costs of the lithium phosphate production step (S616) described later can be reduced, the contamination of impurities during the production of high-purity lithium hydroxide can be minimized, and processing costs during the production of lithium hydroxide can be reduced.

[0047] After the initial separation step (S610), a first evaporation and concentration step (not shown) may be performed. The first evaporation and concentration step is a process of evaporating and concentrating the lithium (Li) solution (filtrate) generated in the initial separation step (S610) to produce lithium carbonate (Li2CO3) crystals. By producing lithium carbonate crystals through the initial separation step (S610) and the first evaporation and concentration step, the amount of phosphoric acid (H3PO4) and sodium hydroxide (NaOH) used in the lithium phosphate production step (S616), described later, can be reduced by more than 50%, and the loss of lithium (Li) distributed as filtrate in the lithium phosphate production step (S616) can be greatly reduced.

[0048] Weak acid leaching process (S612) The weak acid leaching process (S612) is a process in which the cake separated in the pre-separation process (S610) is leached using sulfuric acid (H2SO4). Specifically, the weak acid leaching process (S612) is a process in which, after pre-separating lithium in the pre-separation process (S610), the resulting cake is reduced and leached with sulfuric acid and hydrogen peroxide (H2O2) at 80°C to 85°C for 1 to 4 hours. When dissolving nickel (Ni), cobalt (Co), and manganese (Mn) from the cake from which lithium (Li) has been pre-separated through the pre-separation process (S610), the amount of auxiliary materials used can be minimized, and stable process control in a continuous process is possible.

[0049] Post-separation process (S614) The post-separation step (S614) is a step in which the leaching filtrate produced in the weak acid leaching step (S612) is neutralized to separate it into a lithium (Li) solution and a nickel-cobalt-manganese cake (hereinafter referred to as NCM cake). Specifically, in the post-separation step (S614), the leaching filtrate from the weak acid leaching step (S612) is neutralized with sodium hydroxide (NaOH) (pH 10 to pH 12) and reacted at 70°C to 85°C for 4 to 8 hours, thereby allowing nickel (Ni), cobalt (Co), and manganese (Mn) to precipitate and be recovered, and lithium (Li) to be separated by partitioning as filtrate. The precipitation rate of nickel (Ni), cobalt (Co), and manganese (Mn) in the post-separation step (S614) may be 99.9% or higher.

[0050] Furthermore, in the post-separation step (S614), the filtered NCM cake can be repulped two or more times to remove residual sodium salts (Na salts). For example, the sodium (Na) content in the NCM cake can be reduced from 3.43% to 0.4%. In this specification, the repulping step means a step of repulping the cake in a solid state with water to wash away filtrate components (e.g., residual sodium salts) present in the cake.

[0051] Lithium phosphate manufacturing process (S616) The lithium phosphate production process (S616) is a process in which phosphoric acid (H3PO4) and sodium hydroxide (NaOH) are added to the lithium (Li) solution separated in the post-separation process (S614) to produce a lithium phosphate (Li3PO4) cake. Specifically, phosphoric acid (H3PO4) is added to the lithium (Li) solution separated in the post-separation process (S614) and reacted at 70°C to 85°C for 1 to 4 hours to precipitate and recover lithium (Li) in the form of lithium phosphate (Li3PO4). In addition, sodium hydroxide (NaOH) can be added to neutralize the solution to a pH of 10.0 to 12.0.

[0052] Lithium sulfate solution manufacturing process (S618)

[0053] The lithium sulfate solution manufacturing process (S618) is a process in which lithium sulfate (Li2SO4) solution is manufactured by dissolving lithium carbonate (Li2CO3) crystals recovered by evaporating and concentrating the solution (lithium carbonate (Li2CO3) solution) manufactured in the preceding separation process (S610), and lithium phosphate (Li3PO4) cake produced in the lithium phosphate manufacturing process (S616), in sulfuric acid. For example, the temperature in the lithium sulfate solution manufacturing process (S618) is 60°C to 80°C, the reaction time is 0.5 hours to 3 hours, and the pH is 2.0 or less.

[0054] After the lithium sulfate solution production process (S618), a second evaporation and concentration process (not shown) may be performed. The second evaporation and concentration process is a process of evaporating and concentrating the lithium sulfate solution produced in the lithium sulfate solution production process (S618) to separate lithium sulfate (Li2SO4) crystals from phosphoric acid (H3PO4) filtrate. The phosphoric acid (H3PO4) filtrate can be recycled in the lithium phosphate production process (S616) and used as a by-raw material for lithium precipitation. The evaporated condensate generated in the second evaporation and concentration process can be recycled as a process liquid in the lithium (Li) pre-separation process (S610). Through this, the amount of waste liquid generated outside the system and the amount of fresh water flowing into the system can be reduced.

[0055] The first phosphorus removal step (not shown) is a step in which the lithium sulfate (Li2SO4) crystals produced in the second evaporation concentration step are dissolved in pure water, and then phosphorus (P) is removed using aluminum sulfate (Al2(SO4)3) and caustic soda (NaOH). For example, by adding aluminum sulfate (Al2(SO4)3) to the solution produced in the lithium sulfate solution production step (S618) to adjust the pH to 5.0-6.0 and reacting it at 50°C-70°C for 4-8 hours, most of the phosphorus (P) can be precipitated and removed, and iron (Fe) and other impurities can also be co-precipitated and removed.

[0056] Lithium carbonate manufacturing process (S620) The lithium carbonate production process (S620) is a process in which sodium carbonate (Na2CO3) is added to the lithium sulfate (Li2SO4) produced in the lithium sulfate solution production process (S618) to precipitate lithium carbonate (Li2CO3). For example, in the lithium carbonate production process (S620), sodium carbonate (Na2CO3) is added to the filtrate generated in the first phosphorus removal process and reacted at 80°C to 85°C for 1 to 6 hours to precipitate lithium carbonate.

[0057] Preferably, a repulping step can be performed in the lithium carbonate production step (S620) to remove residual sodium (Na) salts from the cake. In this case, repulping can be performed at 80°C to minimize lithium (Li) loss. The filtrate from the lithium carbonate production step (S620) can be recycled in the lithium phosphate production step (S616).

[0058] Lithium hydroxide solution manufacturing process (S622) The lithium hydroxide solution manufacturing process (S622) is a process in which the lithium carbonate cake produced from the lithium carbonate is added to pure water and dissolved, and then calcium oxide (CaO) is added to produce a lithium hydroxide (LiOH) solution. For example, a lithium hydroxide (LiOH) solution can be produced by adding calcium oxide (CaO) and water to the lithium carbonate cake produced in the lithium carbonate manufacturing process (S620), reacting at 80°C to 100°C for 3 hours or less, and then reacting at 80°C to 100°C for 2 hours or less. Preferably, a repulping process may be performed to recover lithium contained in the calcium carbonate (CaCO3) residue produced in the lithium hydroxide solution manufacturing process (S622).

[0059] Ion exchange resin process (S624) The ion exchange resin step (S624) is a step for removing calcium (Ca) and magnesium (Mg), which are impurities, from the lithium hydroxide (LiOH) solution produced.

[0060] The third evaporation and concentration step (not shown) is a step in which lithium hydroxide (LiOH) crystals are produced by evaporating and concentrating the lithium hydroxide (LiOH) solution produced in the lithium hydroxide solution production step (S622) and / or the ion exchange resin treated solution from which impurities have been removed via the ion exchange resin step (S624). Specifically, in the third evaporation and concentration step, the lithium hydroxide (LiOH) solution and / or the ion exchange resin treated solution can be evaporated and concentrated to produce the LiOH·H2O product.

[0061] Two-stage leaching process (S626) The two-stage leaching process (S626) is a process in which the weak acid leaching cake produced in the weak acid leaching process (S612) and the NCM cake generated in the post-separation process (S614) are leached using sulfuric acid and hydrogen peroxide (H2O2). For example, in the two-stage leaching process (S626), the weak acid leaching cake and the NCM cake from which lithium has been separated can be dissolved in sulfuric acid (H2SO4) at 60°C to 80°C for 2 to 4 hours (pH 1.5 to 2.5). A small amount of reducing agent may be added to improve the dissolution rate of the NCM cake, and in this case, hydrogen peroxide (H2O2) can be used as the reducing agent.

[0062] Preferably, an impurity removal step may be performed to remove impurities from the filtrate produced in the two-stage leaching step (S626). In this case, the impurity removal step may include a first copper removal step and a first aluminum and phosphorus removal step. The first copper removal step (not shown) is a step of adding NaSH to remove copper (Cu), which is an impurity, from the filtrate produced in the two-stage leaching step (S626). The first aluminum and phosphorus removal step (not shown) is a step of injecting caustic soda (NaOH) and oxygen gas (O2) to remove additional impurities, aluminum (Al) and phosphorus (P), from the filtrate produced in the first copper removal step.

[0063] First solvent extraction step (S628) The first solvent extraction step (S628) is a step in which cobalt is extracted using an extractant from the filtrate produced in the two-stage leaching step (S626) and / or the filtrate produced in the impurity removal step described above.

[0064] Preferably, a nickel hydroxide production step and a nickel weak acid leaching step may be performed on the filtrate produced in the first solvent extraction step (S628). For example, the nickel hydroxide production step (not shown) is a step of producing nickel hydroxide (Ni(OH)2) using caustic soda (NaOH) on the filtrate produced in the first solvent extraction step (S628). The nickel weak acid leaching step (not shown) is a step of dissolving the cake produced in the nickel hydroxide production step by adding water, sulfuric acid (H2SO4), and hydrogen peroxide (H2O2).

[0065] First impurity removal step (S630) The first impurity removal step (S630) is a step for removing impurities from the filtrate produced in the first solvent extraction step (S628) and / or from the filtrate produced in the nickel hydroxide production step and the nickel weak acid leaching step. Specifically, the first impurity removal step (S630) may include a second copper removal step and a first aluminum removal step. For example, the second copper removal step is a step of adding sodium hydrogen sulfide (NaSH) to remove copper (Cu), which is an impurity, from the filtrate produced in the nickel weak acid leaching step. The first aluminum removal step is a step of adding caustic soda (NaOH) and injecting oxygen gas (O2) to remove aluminum (Al), which is an additional impurity, from the filtrate produced in the second copper removal step.

[0066] The fourth evaporation and concentration step (not shown) is a step in which the solution generated in the first impurity removal step (S630) is evaporated and concentrated to produce nickel sulfate (NiSO4) crystals.

[0067] Second solvent extraction step (S632) The second solvent extraction step (S632) is a step in which manganese is extracted from the decontaminated liquid produced in the first solvent extraction step (S628) using an extractant.

[0068] Preferably, a first cobalt extraction step (not shown) may be performed on the filtrate generated in the second solvent extraction step (S632). The first cobalt extraction step is a step of extracting cobalt from the filtrate generated in the second solvent extraction step (S632) using an extractant.

[0069] Second impurity removal step (S634) The second impurity removal step (S634) is a step for removing impurities from the filtrate produced in the second solvent extraction step (S632) and / or the filtrate produced in the first cobalt extraction step. Specifically, the second impurity removal step (S634) may include a third copper removal step (not shown) and a second aluminum removal step (not shown). For example, the third copper removal step is a step of adding sodium hydrogen sulfide (NaSH) to remove copper (Cu), an impurity, from the desoldering liquid generated in the first cobalt extraction step. The second aluminum removal step is a step of adding caustic soda (NaOH) and injecting oxygen gas (O2) to remove aluminum (Al), an additional impurity, from the filtrate produced in the third copper removal step.

[0070] The fifth evaporation and concentration step (not shown) is a step in which the filtrate produced in the second impurity removal step (S634) is evaporated and concentrated to produce cobalt sulfate (CoSO4) crystals.

[0071] Third impurity removal step (S636) The third impurity removal step (S636) is a step for removing impurities from the filtrate generated in the second solvent extraction step (S632). Specifically, the third impurity removal step (S636) may include a fourth copper removal step (not shown) and a third aluminum removal step (not shown). The fourth copper removal step is a step of adding sodium hydrogen sulfide (NaSH) to remove copper (Cu) from the filtrate generated in the second solvent extraction step (S632). The third aluminum removal step is a step of injecting caustic soda (NaOH) and oxygen gas (O2) to remove aluminum (Al), an additional impurity, from the filtrate generated in the fourth copper removal step.

[0072] The sixth evaporation and concentration step (not shown) is a step in which the filtrate produced in the third impurity removal step (S636) is evaporated and concentrated to produce manganese sulfate (MnSO4) crystals.

[0073] The present invention will be described in detail below through examples and comparative examples. In the examples, valuable metals were recovered from waste batteries through the process described above. On the other hand, in the comparative examples, valuable metals were recovered in the same manner as in the examples, except that the waste batteries were disassembled from pack units to module units in the disassembly process (S200).

[0074] Table 1 below shows the amount of impurities in the recovered material in the examples and comparative examples. The method for calculating the amount of impurities inflow was as follows. Specifically, the amount of NCM622 waste batteries processed per day was 285.7 tons on a pack basis, 205.5 tons on a module basis after dismantling the pack and removing other parts, and 168.2 tons on a cell basis after dismantling the module and removing other parts. At this time, the amount of impurities inflow was calculated by deriving the ratio of aluminum (Al) and iron (Fe) in the material recovered from the waste batteries in module form.

[0075] [Table 1]

[0076] Table 1 shows that in the example where waste batteries are disassembled from pack units to cell units, the inflow of aluminum (Al) and iron (Fe) is significantly reduced compared to the comparative example. Specifically, the inflow of aluminum (Al) in the example was reduced by 82.4% compared to the comparative example, and the inflow of iron (Fe) was reduced by 100%.

[0077] Table 2 below shows the recovery rates of each valuable metal in the materials recovered in the examples and comparative examples. The recovery rate of each valuable metal refers to the value calculated after removing the loss during the process of recovering the target metal (e.g., Li) in its commercial form (e.g., LiOH). At this time, the weight of the raw material (and slag) containing the target metal was measured using a scale, and the concentration of the leached compound metal was measured by ICP-AES spectroscopy, from which the recovery rate of each metal was calculated.

[0078] [Table 2]

[0079] Table 2 shows that the lithium (Li) recovery rate in the examples was significantly increased compared to the comparative example. Furthermore, unlike the comparative example, manganese (Mn) recovery was possible in the examples.

[0080] While the present invention has been described in relation to some embodiments, it should be understood that various modifications and alterations are possible without departing from the spirit and scope of the invention as understood by a person ordinary in the art to which the invention pertains. Furthermore, such modifications and alterations should be considered to fall within the scope of the claims appended to this specification.

Claims

1. Discharge process for discharging waste batteries; A dismantling process for separating the discharged waste battery into individual cells; A crushing step for crushing the waste batteries that have been disassembled into individual cells; A roasting process for roasting the crushed waste batteries; A crushing step of crushing the roasted waste batteries; and This includes a wet process for extracting and recovering metal from the crushed waste batteries, The aforementioned wet process is, A preliminary separation step involves adding water to the crushed waste battery to separate the lithium solution from the cake. A weak acid leaching step in which the cake separated in the above separation step is leached, A post-separation step in which the leaching filtrate produced in the weak acid leaching step is neutralized to separate the lithium solution from the nickel-cobalt-manganese cake, and A waste battery processing method comprising a two-stage leaching step for leaching the cake leached in the weak acid leaching step and the nickel-cobalt-manganese-based cake separated in the post-separation step.

2. The waste battery disposal method according to claim 1, wherein the waste battery is a battery pack that has reached the end of its lifespan.

3. The waste battery processing method according to claim 1, wherein the waste battery is discharged through the discharge step so that the voltage of the waste battery is 30V or less.

4. The waste battery processing method according to claim 1, wherein the battery cells are crushed to a size of 20 cm or less through the crushing step.

5. The waste battery processing method according to claim 1, wherein the step of separating black mass from the crushed waste batteries is omitted.

6. The waste battery processing method according to claim 1, wherein the discharge step, the dismantling step, the crushing step, the roasting step, and the pulverization step are performed continuously by automated equipment.

7. The waste battery processing method according to claim 1, wherein the discharge step, the dismantling step, and the crushing step are performed by automated equipment using a robot.

8. The waste battery treatment method according to claim 1, wherein the metal compound is recovered through the wet process.

9. The waste battery treatment method according to claim 8, wherein the metal compound comprises at least one selected from the group consisting of lithium hydroxide, lithium carbonate, and lithium phosphate.

10. The waste battery treatment method according to claim 8, wherein the metal compound comprises one sulfate selected from the group consisting of nickel, cobalt, and manganese.

11. The waste battery treatment method according to claim 8, wherein the metal compound includes a nickel-cobalt-manganese compound in solution.

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