Battery shredded material and battery processing method

Abstract

The present invention relates to a battery shredded material and a battery processing method. The battery shredded material for recovering valuable metals from a waste battery has a layered structure including a separator with at least one surface on which a cathode and an anode are stacked, wherein the amount of copper (Cu) in the anode includes 0.01 wt% to 2.5 wt% with respect to 100 wt% of the anode.

Description

Battery shredders and battery disposal methods

[0001] As for waste batteries, it relates to battery shredders extracted from waste battery recycling and a method for processing batteries.

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

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

[0004] In order to utilize the above-mentioned waste batteries, development is actively underway on a waste battery recycling process that performs a preprocess of crushing the waste batteries to produce intermediate materials such as waste battery shreds or black powder, and then recovers valuable metals through a postprocess.

[0005] In the process of processing the above-mentioned waste batteries, pretreatment is crucial to minimize chemical energy reactions and safely dismantle the waste batteries. Various pretreatment methods are utilized, including salt water discharge, electrical discharge, and freezing. Salt water discharge is a representative wet treatment method, while electrical discharge and freezing are representative dry treatment methods.

[0006] The above brine discharge method has the problem of containing more impurities than the dry treatment method. The dry treatment method is advantageous in reducing the input of the impurities. However, among the dry treatment methods, the electric discharge discharges the battery to 0 V for safe battery processing, and in the case of deep discharging to insolubilize the battery, the discharge continues even after all the lithium is extracted from the graphite, and there is a problem in that the copper foil, which is the negative current collector, is oxidized, causing copper ions to leak into the electrolyte.

[0007] Furthermore, there are cases where the separator is penetrated and deposited on the surface of the cathode material. Furthermore, if the shredded material in this state is fed into the downstream process, the copper impurity content may increase, potentially affecting the recovery rate of valuable metals in the downstream process.

[0008] The technical problem to be solved by the present invention is to provide a battery shredder that minimizes copper impurities leaking from battery active materials during battery preprocessing, thereby increasing the efficiency of valuable metal recovery in the downstream process.

[0009] Another technical problem to be solved by the present invention is to provide a battery processing method that provides battery shredder having the aforementioned advantages.

[0010] According to one embodiment of the present invention, the battery shredder is a battery shredder for recovering valuable metals from a spent battery, and has a layered structure including a separator in which a positive electrode and a negative electrode are laminated on at least one surface, and the content of copper (Cu) in the negative electrode may include 0.01 to 2.5 wt% based on 100 wt% of the negative electrode. In one embodiment, the negative electrode includes fluorine (F), and the content of fluorine (F) in the negative electrode may include 9.5 to 15 wt% based on 100 wt% of the negative electrode.

[0011] In one embodiment, the battery shredder may satisfy Equation 1 below.

[0012] <Formula 1>

[0013] 25 ≤ [F] / [Cu] ≤ 250

[0014] (In the above formula 1, [F] and [Cu] represent the contents of fluorine and copper in the cathode, respectively)

[0015] In one embodiment, the battery shredder may satisfy Equation 2 below.

[0016] <Formula 2>

[0017] 0.120 ≤ ([F] + [Cu]) / [C] ≤ 0.180

[0018] (In the above formula 2, [F], [Cu], and [C] represent the contents of fluorine, copper, and graphite in the cathode, respectively)

[0019] In one embodiment, the battery shredder may satisfy conditions 1 and 2 below.

[0020]

[0021] <Condition 1> The above layered structure is a laminated structure having 1 or more layers and 7 or fewer layers.

[0022] <Condition 2> The size of the unit battery shreds is 100 mm or less based on the longest axis among the horizontal, vertical, and height directions.

[0023] In one embodiment, the cathode includes carbon (C), and the content of carbon (C) in the cathode may be 71.0 to 78.0 wt% based on 100 wt% of the cathode.

[0024] According to another embodiment of the present invention, a battery shredder comprises the steps of preparing a battery having a voltage of 2.5 V or higher, freezing the battery, and shredding the frozen battery into battery shredder, wherein the content of copper (Cu) in the negative electrode of the battery shredder may be 0.01 to 2.5 wt% based on 100 wt% of the negative electrode.

[0025] In one embodiment, the battery processing method may satisfy the following equation 3.

[0026] <Formula 3>

[0027]

[0028] (In the above equation 3, x means the voltage state [V] before the battery is crushed, and y means the average content (wt%) of Cu contained in the negative electrode)

[0029] In one embodiment, the method for processing a battery may include freezing the battery at a temperature of -20° C. or lower. In one embodiment, the battery shredder may satisfy the following equation 1.

[0030] <Formula 1>

[0031] 25 ≤ [F] / [Cu] ≤ 250

[0032] (In the above formula 1, [F] and [Cu] represent the contents of fluorine and copper in the cathode, respectively)

[0033] In one embodiment, the battery shredder may satisfy Equation 2 below.

[0034] <Formula 2>

[0035] 0.120 ≤ ([F] + [Cu]) / [C] ≤ 0.180

[0036] (In the above formula 2, [F], [Cu], and [C] represent the contents of fluorine, copper, and graphite in the cathode, respectively)

[0037] In one embodiment, the step of crushing the battery may be performed under conditions of supplying an inert gas, carbon dioxide, nitrogen, water or a combination thereof or under vacuum conditions of 100 torr or less.

[0038] According to one embodiment of the present invention, the battery shredder is provided to control the copper content in the battery shredder to a predetermined range, thereby minimizing copper impurities leaking from battery active materials during battery preprocessing and increasing the efficiency of valuable metal recovery in the downstream process.

[0039] According to another embodiment of the present invention, a method for manufacturing battery shredder is provided to control an initial battery voltage value and perform cryo-shredding, thereby minimizing copper impurities leaking from battery active materials in battery preprocessing and thereby increasing the efficiency of recovery of valuable metals in a downstream process.

[0040] Figure 1 shows an SEM photograph of the surface of a negative electrode material according to one embodiment of the present invention.

[0041] Figure 2 shows an SEM photograph of the surface of a negative electrode material according to a comparative example of the present invention.

[0042] Figure 3 shows an SEM photograph of the surface of a negative electrode material according to a comparative example of the present invention.

[0043] FIGS. 4A to 4H are microstructure photographs for deriving component result values ​​included in a negative electrode material according to examples and comparative examples of the present invention.

[0044] Figure 5 is a graph showing the copper content of the negative electrode material according to battery voltage conditions.

[0045] The terms first, second, and third, etc., are used to describe, but are not limited to, various parts, components, regions, layers, and / or sections. These terms are used only to distinguish one part, component, region, layer, or section from another part, component, region, layer, or section. Accordingly, a first part, component, region, layer, or section described below may be referred to as a second part, component, region, layer, or section without departing from the scope of the present invention.

[0046] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the present invention. As used herein, the singular forms "singular" and "comprising" include plural forms as well, unless the context clearly dictates otherwise. The word "comprising" as used herein specifies a particular feature, region, integer, step, operation, element, and / or component, but does not exclude the presence or addition of other features, regions, integers, steps, operations, elements, and / or components.

[0047] When a part is referred to as being "on" or "over" another part, it can be directly on or over the other part, or there may be other parts intervening. Conversely, when a part is referred to as being "directly on" another part, there are no other parts intervening.

[0048] Although not defined otherwise, all terms, including technical and scientific terms, used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present invention pertains. Terms defined in commonly used dictionaries are further interpreted to have meanings consistent with the relevant technical literature and the present disclosure, and are not to be construed as ideal or overly formal unless otherwise defined.

[0049] Hereinafter, embodiments of the present invention will be described in detail. However, these are presented as examples and the present invention is not limited thereto, and the present invention is defined solely by the scope of the claims set forth below.

[0050] According to one embodiment of the present invention, the unit battery shredder is for recovering valuable metals from waste batteries, and has a layered structure including a separator with a positive electrode and a negative electrode laminated on at least one surface. Specifically, the layered structure may include a configuration in which the positive electrode and the negative electrode are included on one surface of the separator based on the separator. More specifically, the number of layers of the layered structure may correspond to the number of separators.

[0051] The above layered structure includes, for example, one of anode-separator-cathode, separator-cathode, and cathode-separator, and for example, anode-separator-cathode-separator-anode-separator-cathode may have a three-layered layered structure. Specifically, the unit battery shredder may have a predetermined thickness in the thickness direction as at least one or more layers are laminated.

[0052] In one embodiment, the unit battery shredder may satisfy the following condition 1.

[0053] <Condition 1> The above layered structure may be a laminated structure having 1 or more layers and 7 or fewer layers.

[0054] The above-mentioned unit battery shredder may have a layered structure having a laminated structure of one or more layers and no more than seven layers. Specifically, the layered structure may have a layered structure of one or more layers and no more than five layers. As the layered structure is laminated within the above range, the temperature rise of the shredder can be minimized and the heating time can be appropriately taken. If the layered structure is laminated thicker than the upper limit of the above range, the temperature rise excessively increases and the heating time also increases, which may cause a fire due to combustion.

[0055] In one embodiment, the unit battery shredder may satisfy the following condition 2.

[0056]

[0057] <Condition 2> The size of the above unit battery shreds may be 100 mm or less based on the longest axis among the horizontal, vertical, and height directions.

[0058] In one embodiment, the unit battery shredder may have a size of 100 mm or less based on its longitudinal axis. Specifically, the size of the unit battery shredder may be 50 mm or less. If the size of the unit battery shredder is excessively large, there is a problem that the temperature of the battery shredder itself may rise above 100°C, which increases the possibility of a fire occurring.

[0059] In one embodiment, the content of copper (Cu) in the cathode may include 0.01 to 2.5 wt% based on 100 wt% of the cathode. Specifically, the content of copper may include 0.01 to 0.42 wt%, more specifically, 0.04 to 0.34 wt%, and even more specifically, 0.11 to 0.34 wt%. When the content of copper exceeds the upper limit of the above-mentioned range, there is a problem in that the extraction recovery rate of valuable metals is reduced due to Cu impurities in the raw material input to the downstream process.

[0060] In one embodiment, the content of fluorine (F) in the cathode may be 9.5 to 15.0 wt% based on 100 wt% of the cathode. Specifically, the content of fluorine may be 9.55 to 12.5 wt%, and more specifically, 9.55 to 11.71 wt%.

[0061] When the fluorine content satisfies the aforementioned range, lithium compounds such as lithium fluoride are appropriately formed within the negative electrode, and the lithium compounds can be easily separated in a subsequent process, thereby increasing the lithium recovery rate. When the fluorine content exceeds the lower limit of the aforementioned range, there is a problem in that the recovery rate of valuable metals is reduced when the battery shredder is leached.

[0062] In one embodiment, the content of carbon (C) in the negative electrode may be 71.0 to 78.0 wt% based on 100 wt% of the negative electrode. Specifically, the content of carbon may be 73.0 to 78.0 wt%, and more specifically, 73.89 to 77.67 wt%. Since the content of carbon satisfies the above-mentioned range, the negative electrode can be easily separated in a subsequent process, thereby increasing the recovery rate of valuable metals.

[0063] In one embodiment, the battery shredder may satisfy Equation 1 below.

[0064] <Formula 1>

[0065] 25 ≤ [F] / [Cu] ≤ 250

[0066] (In the above formula 1, [F] and [Cu] represent the contents of fluorine and copper in the cathode, respectively)

[0067] The above equation 1 represents the ratio of the content of fluorine to copper in the cathode, and may be an indicator of the degree of copper contamination. The above equation 1 may satisfy a ratio of 25 to 250, specifically, 30 to 240, and more specifically, 31.97 to 238.75.

[0068] Since the above formula 1 satisfies the above-mentioned range, lithium fluoride in the negative electrode is appropriately contained in the battery shreds, so that lithium fluoride can be easily separated from the negative electrode by water leaching in a post-process, thereby increasing the recovery rate of lithium. If the above formula 1 exceeds the upper or lower limit of the above-mentioned range, there is a problem that fluorine and copper are not formed in the form of a compound that can be separated in a post-process, thereby lowering the recovery rate of valuable metals.

[0069] In one embodiment, the battery shredder may satisfy Equation 2 below.

[0070] <Formula 2>

[0071] 0.120 ≤ ([F] + [Cu]) / [C] ≤ 0.180

[0072] (In the above formula 2, [F], [Cu], and [C] represent the contents of fluorine, copper, and graphite in the cathode, respectively)

[0073] The above equation 2 represents the ratio of the total amount of copper and fluorine to carbon in the negative electrode, and can be an indicator of copper contamination and discharge. The equation 2 can satisfy 0.120 to 0.180, specifically, 0.122 to 0.160, and more specifically, 0.124 to 0.158. By satisfying the above-mentioned range, the equation 2 can minimize copper impurities leaking from the battery active material, thereby increasing the efficiency of valuable metal recovery in the downstream process. If the equation 2 is outside the above-mentioned range, when the battery shredder is input into the downstream process, there is a problem that the content of copper impurities is high, thereby lowering the efficiency of valuable metal recovery.

[0074] According to another embodiment of the present invention, a battery processing method comprises the steps of preparing a battery, freezing the battery, and crushing the frozen battery. The battery processing method may be a method for processing various types of batteries containing lithium ions, and the battery may be, for example, a lithium secondary battery separated from an automobile, a secondary battery separated from an electronic device such as a cell phone, a camera, or a laptop, and specifically, a lithium secondary battery.

[0075] In one embodiment, in the step of preparing the battery, the battery may have a voltage of 2.5 V or higher. The battery of the present invention may have a voltage of 2.5 to 4.5 V. Specifically, the voltage may be 2.5 to 4.0 V, and more specifically, 3.0 to 4.0 V.

[0076] In one embodiment, the step of preparing the battery may include a step of electrically discharging the battery so that the battery has a voltage of 2.5 V or higher. The step of electrically discharging may mean applying a current to the battery to lower the voltage of the battery. The step of electrically discharging may be controlled so that the battery has a voltage of 2.5 V or higher.

[0077] In the step of preparing the battery, the voltage of the battery may be measured based on the voltage of the cells within the battery. Specifically, the step of measuring the voltage may be performed by using a general tester to contact the terminals of the battery according to the positive and negative poles, thereby measuring the voltage of the cells. The step of measuring the voltage of the battery may be a step of determining the state of the battery in order to cool the battery.

[0078] The step of freezing the battery is performed at a temperature sufficient to freeze the electrolyte contained within the battery. Specifically, the step of freezing may be performed at a temperature of, for example, -20°C or lower. Specifically, the temperature may be performed in a temperature range of -150 to -20°C, more specifically, -150 to -50°C, and even more specifically, -80 to -60°C.

[0079] When the battery is frozen in the above temperature range, the voltage remaining slightly inside the battery, for example, about 2 V to 3 V, is lowered to close to 0 V, and even if a short circuit occurs in which the positive and negative electrodes are in direct contact, no battery reaction occurs, so the battery temperature does not increase, and gas generation and combustion of the electrolyte do not occur. In addition, since the electrolyte is in a frozen state or in a state in which vaporization is suppressed, the mobility of lithium ions is very low, so that the conduction characteristics according to the movement of lithium ions can be significantly reduced, and since vaporization of the electrolyte does not occur, flammable gases such as ethylene, propylene, and hydrogen can not be generated.

[0080] If the above freezing process is outside the above temperature range, for example, if it cools to a temperature higher than -60℃, the voltage remaining inside the battery will not be lowered to 0 V, so a battery reaction due to a short circuit may occur, and the electrolyte will not be completely frozen, which is not appropriate. In addition, if it is cooled to -150℃, the electrolyte is sufficiently frozen, and the voltage inside the battery will also be lowered to 0 V, so there is no need to lower the temperature below this. In this way, the battery processing method has the advantage of preventing the risk of fire that may occur during the battery crushing process by including a freezing step before crushing a battery such as a lithium secondary battery.

[0081] The step of shredding the frozen battery may refer to a process of applying shock or pressure to the battery so that a portion of the battery detaches from the battery. In one embodiment, the step of shredding the battery may refer to a process of crushing the battery, a process of cutting the battery, a process of compressing the battery, or a combination thereof. Specifically, the step of shredding may include any process that can destroy the battery to obtain small-sized shredded materials.

[0082] In one embodiment, the step of crushing the battery may include any process that destroys the battery by compressing the frozen battery or applying an external force, such as a shear force or a tensile force. The step of crushing the battery may be performed, for example, using a crusher.

[0083] 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.

[0084] In one embodiment, the step of crushing the battery can be performed under conditions of supplying an inert gas, carbon dioxide, nitrogen, water, or a combination thereof, or under vacuum conditions of 100 torr or less. For example, when the process of freezing the battery is performed by cooling it in a temperature range of -60 to -20°C, when performed under the above-described conditions, the supply of oxygen can be suppressed, preventing the electrolyte from reacting with oxygen, thereby preventing an explosion caused by this, and the vaporization of the electrolyte can be suppressed, thereby preventing the generation of flammable gases such as ethylene, propylene, or hydrogen.

[0085] In one embodiment, at least one of the unit battery shreds included in the battery shreds may satisfy the following condition 1.

[0086] Condition 1

[0087] The above layered structure may have one or more layers and seven or fewer layers.

[0088] The above condition 1 may mean that the layered structure of the unit battery shredder including a separator with a positive or negative electrode laminated on at least one surface is controlled in the step of shredding into a layered structure of 1 or more layers and 7 or fewer layers.

[0089] In one embodiment, the layered structure may be a laminated structure having 1 to 7 layers. Specifically, the layered structure may be a laminated structure having 1 to 5 layers. As the layered structure is laminated within the above range, the temperature rise of the shredded material can be minimized and the heating time can be appropriately taken. If the layered structure is laminated thicker than the upper limit of the above range, the temperature rise excessively increases and the heating time also increases, which may cause combustion.

[0090] In one embodiment, at least one of the unit battery shreds included in the battery shreds may satisfy the following condition 2.

[0091] Condition 2

[0092] The size of the unit battery shreds may be 100 mm or less based on the long axis, which is the longest axis among the horizontal, vertical, and height directions.

[0093] In one embodiment, the size of the unit battery shreds, specifically, the longest axis among the horizontal, vertical, and height directions, may be controlled in the shredding step to be 100 mm or less, specifically 50 mm or less. If the maximum size of the battery shreds is greater than 100 mm, the heat generation temperature caused by instability as the battery shreds are shredded may rise to a temperature range of 120°C, which is the average vaporization temperature of the electrolyte, which may cause stability problems such as fire.

[0094] In one embodiment, the battery shredder may satisfy the following condition 3.

[0095] Condition 3

[0096] The tap density of the above-mentioned shredded battery waste is 200 to 600 kg / m 3 am.

[0097] Tapped density usually refers to the apparent density obtained by mechanically tapping a measuring container containing a powder sample. Specifically, in order to determine the tapped density characteristics of the lithium-ion battery shredder, a commercial battery module consisting of about 30 cells weighing 30 kg was crushed with a crusher, placed in a case (volume: 0.4 m wide × 0.7 m long × 0.44 m high) manufactured to stabilize the shredder, and mechanically tapped to measure the apparent density. More specifically, the density (ρ = M / V) was obtained by dividing the battery weight (M, kg) by the case volume (V, m3). The tapped density of the unit battery shredder calculated by the above-mentioned method was 200 to 600 kg / m 3 Specifically, the tap density is 200 to 300 kg / m 3 It could be.

[0098] If the tap density exceeds the upper limit, there is a risk of fire due to the instantaneous generation of heat by the short circuit of the densely stacked pieces of shredded material, and there is a problem of reduced stabilization processing capacity due to the narrow space through which the electrolyte can escape to the outside. If the tap density exceeds the lower limit, there is a problem of many gaps being created between the shredded material and the material taking up a large volume, requiring an additional pressurization process to transport it to the subsequent process.

[0099]

[0100] Hereinafter, preferred embodiments and comparative examples of the present invention are described. However, the following examples are only preferred embodiments of the present invention, and the present invention is not limited to the following examples.

[0101]

[0102] <Experimental Example 1> - Analysis of components on the cathode surface

[0103] <Example> - Freezing crushing with voltage of 3 V or higher

[0104] Spent batteries with a voltage of 3 V or higher were prepared and cryo-crushing was performed. At this time, in order to prepare spent batteries with a voltage of 3 V or higher, the SOC was controlled to 0% or higher through electric discharge, and the cryo-crushing was performed under conditions of -70°C. Through the cryo-crushing, a battery shredder in which each component was sequentially stacked, such as a cathode-separator-cathode, was obtained.

[0105] Figure 1 shows an SEM photograph of the surface of a negative electrode material according to one embodiment of the present invention.

[0106] Referring to Figure 1, it can be confirmed that in Example 1, no Cu contamination is observed on the surface of the negative electrode carbon material.

[0107]

[0108] <Comparative Example 1> - 0 V discharge

[0109] A spent battery was prepared and forced discharge was performed to bring the battery voltage to 0 V through electric discharge. Afterwards, the discharged battery was shredded at room temperature to obtain battery shreds.

[0110]

[0111] <Comparative Example 2> - - 0.4 V discharge (over-discharge)

[0112] A spent battery was prepared and over-discharged to a voltage of -0.4 V through electric discharge. Afterwards, the discharged battery was crushed at room temperature to obtain battery shreds.

[0113]

[0114] <Comparative Example 3> - - 0.8 V discharge (over-discharge)

[0115] A spent battery was prepared and overdischarged to a voltage of -0.8 V through electric discharge. The discharged battery was then crushed at room temperature to obtain battery shreds.

[0116]

[0117] Figure 2 shows an SEM photograph of the surface of a negative electrode material according to a comparative example of the present invention.

[0118] Fig. 2 is an SEM photograph of the surface of a cathode material when forced discharge was performed as in Comparative Example 1 of the present invention. Compared to Fig. 1, Fig. 2 shows that the area of ​​the white region, which is the area contaminated with copper, is larger.

[0119] Figure 3 shows an SEM photograph of the surface of a negative electrode material according to a comparative example of the present invention.

[0120] Fig. 3 shows that when over-discharge was performed as in Comparative Example 3 of the present invention, copper contamination was more severe compared to Comparative Example 1. Specifically, it can be seen that the area of ​​the white area, which is the area where copper was contaminated, is larger in the battery shreds subjected to over-discharge compared to Figs. 1 and 2.

[0121]

[0122] Table 1 below shows the results of the components contained in the cathode material of the battery shredder according to the battery voltage conditions. The results of the components contained in the cathode material were measured using the method below.

[0123] Results of components included in the cathode material: The types and contents of chemical components in the microstructure were measured using the X-ray energy emitted by irradiating electron beams using a SEM-EDX detector.

[0124] FIGS. 4A to 4H are microstructure photographs for deriving component result values ​​included in a negative electrode material according to examples and comparative examples of the present invention.

[0125] FIGS. 4A and 4B show the microstructure of a negative electrode material according to an embodiment of the present invention, FIGS. 4C and 4D show the microstructure of a negative electrode material according to Comparative Example 1 of the present invention, FIGS. 4E and 4F show the microstructure of a negative electrode material according to Comparative Example 2 of the present invention, and FIGS. 4G and 4H show the microstructure of a negative electrode material according to Comparative Example 3 of the present invention.

[0126] Voltage display COFAlPSMnCoNiCuFormula 1Formula 2Note 3.2 VA177.678.8810.870.391.4200.170.060.180.3431.970.144Example 1A277.110.59.550.321.510.380.28-0.310.04238.750.124A374.9410.2311.10.121.70.370.310.180.940.11100.910.150A474.5510.8211.440.471.620.410.08-0.280.3334.670.158A573.8911.7111.090.161.60.350. 260.070.650.2250.410.153A676.3910.0910.790.481.58--0.020.330.3332.700.1460VB180.178.464.320.730.841.32000.333.831.130.102Comparative Example 1B280.198.454.550.370.881.51---4.051.120.107B380.498.644.280.220.871.440.08--3.991.070.103B479.2410.373.760.250.751.47 -0.210.163.790.990.095B579.968.64.140.510.891.340.27--4.290.970.105B678.9210.214.190.340.931.230.12-0.233.841.090.102-0.4VC179.288.494.721.2601.5100.110.214.441.060.116Comparative Example 2C278.489.525.150.070.981.560.20.030.043.981.290.116C378.089.65.050.241 .311.55-0.070.393.71.360.112C478.18.295.78-1.21.71-0.190.584.171.390.127C577.239.355.320.141.161.570.11-0.794.341.230.125C676.4210.035.390.061.141.750.350.30.414.141.300.125-0.8VD152.116.4611.140.054.050.75--0.614.850.750.499Comparative Example3D282.337.223.570.131.910.350.130.130.034.20.850.094D381.587.264.350.061.980.180.14-04.450.980.108D456.3317.498.7-3.90.570.120.020.0212.860.680.383D555.2417.249.190.193.92-0.320.010.0713.820.660.417D671.7811.555.820.032.550.410.1--7.750.750.189Equation 1: F / CuEquation 2: (F+Cu) / C.

[0127] Looking at Table 1 above, it was confirmed that when electric discharge was performed as in the comparative examples, the content of copper (Cu), which acts as an impurity in the post-process, was high. This is because, when the battery was forcedly discharged, the discharge continued even after all the lithium was extracted from the graphite, which oxidized the copper foil, which is the negative electrode current collector, and caused copper ions to leak into the electrolyte, thereby confirming that the content of copper in the negative electrode increased. In contrast, in the examples, by performing freeze-crushing without electric discharge, it was confirmed that the content of copper in the negative electrode material was lower than in the comparative examples. Looking at the effects of the examples and the comparative examples, when battery shredders with a low copper content, as in the examples, are input to a post-process such as wet treatment, there is an advantage of a high recovery rate of valuable metals due to a low content of copper as an impurity. Specifically, in recycling the negative electrode material as in the examples, freeze-crushing includes copper impurities, but in the case of over-discharge, copper penetrates the graphite microstructure layer, making separation difficult.

[0128]

[0129] <Experimental Example 2> - Average copper content according to voltage before battery shredding

[0130] Based on the morphological characteristics of the cathode and anode materials, the Cu content of the cathode material can be expressed by the following equation 3.

[0131] <Formula 3>

[0132]

[0133] (In the above equation 3, x means the voltage state [V] before the battery is crushed, and y means the average content (wt%) of Cu contained in the negative electrode)

[0134] Figure 5 is a graph showing the copper content of the negative electrode material according to battery voltage conditions.

[0135] Referring to Fig. 5, it can be confirmed that the Cu content of the negative electrode material satisfies the range of about 1.5 wt% when the battery voltage condition is 0.5 to 1 V or higher. When a complete discharge is performed through a conventional electric discharge, it was confirmed that the Cu content has a range of about 3.8 wt%. Specifically, when the average value of the Cu content according to the discharge conditions and voltage of Table 1 was obtained and fitted with an exponential function, the copper content within the aforementioned range could be confirmed.

[0136]

[0137] Although the preferred embodiments have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements made by those skilled in the art using the basic concepts defined in the following claims also fall within the scope of the present invention.

Claims

1. As a battery shredder for recovering valuable metals from waste batteries, A layered structure including a separator in which the positive and negative electrodes are laminated on at least one surface, A battery scrap material comprising a copper (Cu) content in the cathode of 0.01 to 2.5 wt% based on 100 wt% of the cathode.

2. In paragraph 1, The above cathode contains fluorine (F), A battery shredder comprising 9.5 to 15 wt% of fluorine (F) in the cathode based on 100 wt% of the cathode.

3. In paragraph 1, Battery shreds satisfying the following equation 1. <Formula 1> 25 ≤ [F] / [Cu] ≤ 250 (In the above formula 1, [F] and [Cu] represent the contents of fluorine and copper in the cathode, respectively) 4. In paragraph 1, Battery shreds satisfying the following equation 2. <Formula 2> 0.120 ≤ ([F] + [Cu]) / [C] ≤ 0.180 (In the above formula 2, [F], [Cu], and [C] represent the contents of fluorine, copper, and graphite in the cathode, respectively) 5. In paragraph 1, Battery shredder comprising at least one unit battery shredder satisfying at least one of the following conditions 1 and 2. <Condition 1> The above layered structure is a laminated structure having 1 or more layers and 7 or fewer layers. <Condition 2> The size of the unit battery shreds based on the long axis, which is the longest axis among the horizontal, vertical, and height directions, is 100 mm or less.

6. In paragraph 1, The above cathode contains carbon (C), A battery shredder comprising a carbon (C) content in the negative electrode of 71.0 to 78.0 wt% based on 100 wt% of the negative electrode. Step of preparing a battery having a voltage of 2.5 V or higher; Step of freezing the battery; and Comprising the step of crushing the frozen battery into battery shredders, A battery processing method, wherein the content of copper (Cu) in the cathode of the above battery shreds comprises 0.01 to 2.5 wt% based on 100 wt% of the cathode.

8. In paragraph 7, A battery processing method satisfying the following equation 3. <Formula 3> (In the above equation 3, x means the voltage state [V] before battery fracture, and y means the average content (wt%) of Cu contained in the negative electrode) 9. In paragraph 7, A battery processing method wherein the step of freezing the battery is performed at a temperature of -20°C or lower.

10. In paragraph 7, The above battery shredder is a battery processing method that satisfies the following equation 1. <Formula 1> 25 ≤ [F] / [Cu] ≤ 250 (In the above formula 1, [F] and [Cu] represent the contents of fluorine and copper in the cathode, respectively) 11. In paragraph 7, The above battery shredder is a battery processing method that satisfies the following equation 2. <Formula 2> 0.120 ≤ ([F] + [Cu]) / [C] ≤ 0.180 (In the above formula 2, [F], [Cu], and [C] represent the contents of fluorine, copper, and graphite in the cathode, respectively) 12. In paragraph 7, A method for processing batteries, wherein the step of crushing the batteries is performed under conditions of supplying an inert gas, carbon dioxide, nitrogen, water or a combination thereof, or under vacuum conditions of 100 torr or less.

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