WO2025135683A1 - Battery shredded material and battery processing method - Google Patents

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 shredder and battery disposal methods

As for waste batteries, it relates to battery shreds extracted from waste battery recycling and a method for processing batteries.

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 and salt used as the electrolyte are mainly a mixture of carbonate organic substances such as ethylene carbonate and propylene carbonate, and LiPF ₆ is used as a representative salt.

In order to utilize the above-mentioned waste batteries, development is actively underway for 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 a postprocess to recover valuable metals.

In the process of processing the above-mentioned waste batteries, pre-processing is very important to minimize chemical energy reactions in order to safely crush the waste batteries. Various methods such as salt water discharge, electric discharge, and freezing treatment are utilized for the above-mentioned pre-processing. The salt water discharge is a representative wet treatment method, and the electric discharge and freezing treatment methods are representative dry treatment methods.

The above brine discharge has a problem in that it contains many impurities compared to the dry treatment method. The dry treatment method is advantageous in order to reduce the input of the impurities. However, among the dry treatment methods, in the case of deep discharging to insolubilize the battery while discharging the battery to 0 V for safe battery treatment, the discharge continues even after all lithium is removed from the graphite, and there is a problem in that the copper foil, which is the negative current collector, is oxidized and copper ions are released into the electrolyte.

And, there are cases where the separator is penetrated and deposited on the surface of the cathode material. In addition, if the shredded material in that state is input into the downstream process, the content of copper impurities may increase, which may cause problems in the recovery rate of valuable metals in the downstream process.

The technical problem to be solved by the present invention is to provide battery scrap that minimizes copper impurities leaking from battery active materials in battery preprocessing and increases the efficiency of valuable metal recovery in downstream processes.

Another technical problem to be solved by the present invention is to provide a battery processing method which provides battery shreds having the aforementioned advantages.

According to one embodiment of the present invention, the battery scrap is a battery scrap for recovering valuable metals from waste batteries, 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.

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

<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)

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

<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)

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

<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.

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

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 shredders, wherein the content of copper (Cu) in the negative electrode of the battery shredders may include 0.01 to 2.5 wt% based on 100 wt% of the negative electrode.

In one embodiment, the battery processing method can satisfy the following equation 3.

<Formula 3>

(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)

In one embodiment, the battery processing method may be performed at a temperature of -20° C. or lower. In one embodiment, the battery shreds may satisfy 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)

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

<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)

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.

According to one embodiment of the present invention, the battery shredder controls the copper content in the battery shredder to a predetermined range, thereby minimizing copper impurities leaking from battery active materials during battery preprocessing, thereby providing battery shredder that increases the efficiency of valuable metal recovery in a downstream process.

According to another embodiment of the present invention, a method for manufacturing battery shreds 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 recovering valuable metals in a downstream process.

Figure 1 shows an SEM photograph of the surface of a cathode material according to one embodiment of the present invention.

Figure 2 shows an SEM photograph of the surface of a cathode material according to a comparative example of the present invention.

Figure 3 shows an SEM photograph of the surface of a cathode material according to a comparative example of the present invention.

FIGS. 4A to 4H are microstructure photographs for deriving component result values included in a cathode material according to examples and comparative examples of the present invention.

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

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.

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.

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 in which a cathode and a positive electrode are laminated on at least one surface. Specifically, the layered structure may include a configuration in which the cathode and the positive 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.

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.

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

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

The above unit battery shredder may have a layered structure having a laminated structure of 1 to 7 layers. Specifically, the layered structure may have a layered structure of 1 to 5 layers. As the layered structure is laminated within the above range, the temperature rise of the shredder may be minimized, and the heating time may be appropriately taken. If the layered structure is laminated thicker than the upper limit of the above range, the temperature rise may excessively increase, and the heating time may also increase, which may cause a fire as it is combusted.

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

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

In one embodiment, the unit battery shreds may have a size of 100 mm or less based on the longitudinal axis. Specifically, the size of the unit battery shreds may be 50 mm or less. If the size of the unit battery shreds is excessively large, there is a problem that the temperature of the battery shreds themselves may rise to 100° C. or more, which may lead to a high possibility of a fire occurring.

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 is outside the upper limit of the above-mentioned range, there is a problem that the extraction recovery rate of valuable metals is reduced due to Cu impurities in the raw material input to the downstream process.

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

When the content of the fluorine satisfies the above-mentioned range, a lithium compound such as lithium fluoride in the negative electrode is appropriately formed, and the lithium compound can be easily separated in a post-process to increase the recovery rate of lithium. When the content of the fluorine exceeds the lower limit of the above-mentioned range, there is a problem that the recovery rate of valuable metals is reduced when the battery shreds are leached.

In one embodiment, the content of carbon (C) in the cathode may include 71.0 to 78.0 wt% based on 100 wt% of the cathode. Specifically, the content of carbon may include 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 cathode can be easily separated in a subsequent process, thereby increasing the recovery rate of valuable metals.

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

<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)

The above formula 1 represents the ratio of the content of fluorine to copper in the cathode, and can be an indicator of the degree of copper contamination. The above formula 1 can satisfy 25 to 250, specifically, 30 to 240, and more specifically, 31.97 to 238.75.

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 the 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 the post-process, thereby lowering the recovery rate of valuable metals.

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

<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)

The above equation 2 represents the ratio of the total amount of copper and fluorine to carbon in the cathode, and can be an indicator of the degree 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 recovering valuable metals in the downstream process. If the equation 2 is out of the above-mentioned range, when the battery shreds are input to the downstream process, there is a problem that the content of copper impurities is high, thereby lowering the efficiency of recovering valuable metals.

According to another embodiment of the present invention, a battery processing method includes a step of preparing a battery, a step of freezing the battery, and a step of crushing the frozen battery. The battery processing method may be a method of 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, and specifically, a lithium secondary battery.

In one embodiment, in the step of preparing the battery, the battery may have a voltage of 2.5 V or more. 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, more specifically, 3.0 to 4.0 V.

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.

In the step of preparing the battery, the voltage of the battery can be measured based on the voltage of the cells in the battery. Specifically, the step of measuring the voltage can be performed by using a general tester to contact the terminals corresponding to the + and - poles of the battery to measure the voltage of the cell. The step of measuring the voltage of the battery can be a step of determining the state of the battery in order to freeze the battery.

The step of freezing the battery is performed at a temperature sufficient to freeze the electrolyte contained in 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.

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, so that even if a short circuit occurs in which the positive and negative electrodes are in direct contact, a battery reaction does not occur, 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 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.

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 it to a lower temperature. In this way, the battery processing method has the advantage of preventing the risk of fire that may occur in the battery crushing process by including a freezing step before crushing a battery such as a lithium secondary battery.

The step of crushing the frozen 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 frozen battery or destroying the battery by 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.

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 performed under vacuum atmosphere conditions of 100 torr or less. For example, when the process of freezing the battery is performed by cooling in a temperature range of -60 to -20℃, when performed under the above-mentioned conditions, the supply of oxygen can be suppressed, preventing the electrolyte from reacting with oxygen, preventing an explosion caused thereby, and suppressing the vaporization of the electrolyte, so as not to generate flammable gases such as ethylene, propylene, or hydrogen.

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

<Condition 1>

The above layered structure may have 1 or more layers and 7 or fewer layers.

The above condition 1 may mean that the layered structure of the unit battery shredder including a separator having 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.

In one embodiment, the layered structure may be a laminated structure having 1 or more layers and 7 or fewer layers. Specifically, the layered structure may be a laminated structure having 1 or more layers and 5 or fewer layers. As the layered structure is laminated within the above range, the temperature rise amount 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 amount excessively increases and the heating time also increases, which causes a problem of combustion.

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

<Condition 2>

The size of the unit battery shreds based on the long axis, which is the longest axis among the length, width, and height directions, may be 100 mm or less.

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, and thus a problem in stability, such as a fire, may occur.

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

<Condition 3>

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

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 tap density characteristics of the lithium-ion battery shredder, a commercialized battery module consisting of about 30 cells weighing 30 kg was crushed by 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 tap density of the unit battery shredder calculated by the above-described method is 200 to 600 kg/ ^m3 . Specifically, the tap density can be 200 to 300 kg/ ^m3 .

If the above tap density exceeds the upper limit, there is a risk of fire due to instantaneous heat generation 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 above tap density exceeds the lower limit, there is a problem of many gaps between the shredded material and the volume is large, requiring an additional pressurization process to transport it to the post-process.

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 1> - Analysis of components on the cathode surface

<Example> - Freezing fracture at voltages of 3 V or higher

A spent battery with a voltage of 3 V or higher was prepared and cryo-crushing was performed. At this time, in order to prepare a spent battery with a voltage of 3 V or higher, the SOC was controlled to 0% or higher by electric discharge, and the cryo-crushing was performed under conditions of -70°C. Through the cryo-crushing, a battery shredded product in which each component was sequentially laminated, such as a cathode-separator-cathode, was obtained.

Figure 1 shows an SEM photograph of the surface of a cathode material according to one embodiment of the present invention.

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.

<Comparative Example 1> - 0 V Discharge

A waste battery was prepared and forced discharge was performed so that the voltage of the battery became 0 V through electric discharge. Afterwards, the discharged battery was crushed at room temperature to obtain battery crushed material.

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

A spent battery was prepared and over-discharged to make the voltage of the battery reach -0.4 V through electric discharge. After that, the discharged battery was crushed at room temperature to obtain battery crushed material.

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

A used battery was prepared and over-discharge was performed so that the voltage of the battery became -0.8 V through electric discharge. After that, the discharged battery was crushed at room temperature to obtain battery crushed material.

Figure 2 shows an SEM photograph of the surface of a cathode material according to a comparative example of the present invention.

Fig. 2 is a SEM photograph of the surface of a cathode material when forced discharge is 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.

Figure 3 shows an SEM photograph of the surface of a cathode material according to a comparative example of the present invention.

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 confirmed that the area of the white area, which is the area where copper is contaminated, is wider in the battery shreds where over-discharge was performed compared to FIGS. 1 and 2.

Table 1 below shows the result values of components contained in the cathode material in the cathode among the battery shreds according to the battery voltage conditions. The result values of components contained in the cathode material were measured using the method below.

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.

FIGS. 4A to 4H are microstructure photographs for deriving component result values included in a cathode material according to examples and comparative examples of the present invention.

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.

voltage mark C O F Al P S Mn Co Ni Cu Equation 1 Equation 2 note 3.2 V A1 77.67 8.88 10.87 0.39 1.42 0 0.17 0.06 0.18 0.34 31.97 0.144 line
city
Example 1 A2 77.1 10.5 9.55 0.32 1.51 0.38 0.28 - 0.31 0.04 238.75 0.124 A3 74.94 10.23 11.1 0.12 1.7 0.37 0.31 0.18 0.94 0.11 100.91 0.150 A4 74.55 10.82 11.44 0.47 1.62 0.41 0.08 - 0.28 0.33 34.67 0.158 A5 73.89 11.71 11.09 0.16 1.6 0.35 0.26 0.07 0.65 0.22 50.41 0.153 A6 76.39 10.09 10.79 0.48 1.58 - - 0.02 0.33 0.33 32.70 0.146 0
V B1 80.17 8.46 4.32 0.73 0.84 1.32 0 0 0.33 3.83 1.13 0.102 rain
school
Example 1 B2 80.19 8.45 4.55 0.37 0.88 1.51 - - - 4.05 1.12 0.107 B3 80.49 8.64 4.28 0.22 0.87 1.44 0.08 - - 3.99 1.07 0.103 B4 79.24 10.37 3.76 0.25 0.75 1.47 - 0.21 0.16 3.79 0.99 0.095 B5 79.96 8.6 4.14 0.51 0.89 1.34 0.27 - - 4.29 0.97 0.105 B6 78.92 10.21 4.19 0.34 0.93 1.23 0.12 - 0.23 3.84 1.09 0.102 -0.4
V C1 79.28 8.49 4.72 1.26 0 1.51 0 0.11 0.21 4.44 1.06 0.116 rain
school
Example 2 C2 78.48 9.52 5.15 0.07 0.98 1.56 0.2 0.03 0.04 3.98 1.29 0.116 C3 78.08 9.6 5.05 0.24 1.31 1.55 - 0.07 0.39 3.7 1.36 0.112 C4 78.1 8.29 5.78 - 1.2 1.71 - 0.19 0.58 4.17 1.39 0.127 C5 77.23 9.35 5.32 0.14 1.16 1.57 0.11 - 0.79 4.34 1.23 0.125 C6 76.42 10.03 5.39 0.06 1.14 1.75 0.35 0.3 0.41 4.14 1.30 0.125 -0.8
V D1 52.1 16.46 11.14 0.05 4.05 0.75 - - 0.6 14.85 0.75 0.499 rain
school
Example 3 D2 82.33 7.22 3.57 0.13 1.91 0.35 0.13 0.13 0.03 4.2 0.85 0.094 D3 81.58 7.26 4.35 0.06 1.98 0.18 0.14 - 0 4.45 0.98 0.108 D4 56.33 17.49 8.7 - 3.9 0.57 0.12 0.02 0.02 12.86 0.68 0.383 D5 55.24 17.24 9.19 0.19 3.92 - 0.32 0.01 0.07 13.82 0.66 0.417 D6 71.78 11.55 5.82 0.03 2.55 0.41 0.1 - - 7.75 0.75 0.189 Equation 1: F/Cu
Equation 2: (F+Cu)/C

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 lithium was removed from the graphite, and the copper foil, which is the negative electrode current collector, was oxidized, causing copper ions to be released 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 shreds 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 because the content of copper, which is an impurity, is low. Specifically, as in the examples, when recycling the negative electrode material, freeze-crushing includes copper impurities, but in the case of over-discharge, there is a problem that copper penetrates the graphite microstructure layer, making separation difficult.

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

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.

<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)

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

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 in the above-mentioned range could be confirmed.

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 (12)

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. In the first paragraph, 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. In the first paragraph, 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) In the first paragraph, 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) In the first paragraph, 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. In the first paragraph, 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. In Article 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) In Article 7, A battery processing method wherein the step of freezing the battery is performed at a temperature of -20°C or lower. In Article 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) In Article 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) In Article 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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