Battery shred and method of disposing battery

Abstract

The present invention relates to a battery shred and a method for disposing a battery. The battery shred of the present invention is for recovering valuable metals from a waste battery, and comprises: a positive electrode; a negative electrode disposed on the positive electrode; and a separator disposed between the positive electrode and the negative electrode. The negative electrode contains fluorine (F) having a content of 5.0-15.0 wt% based on 100 wt% of the total negative electrode.

Description

Battery shredders and battery disposal methods

[0001] As for waste batteries, it relates to battery shreds recovered from a battery processing method and a battery processing method.

[0002] Electric vehicles, the supply and demand of which are rapidly increasing due to environmental concerns, require battery technology as a key element. The disposal of these waste batteries, generated from these electric vehicles, is becoming a social issue. These waste batteries, which use lithium-ion batteries, contain organic solvents, explosive materials, and heavy metals such as nickel, cobalt, manganese, iron, and phosphorus (Ni), carbon, and other electrolyte materials. Among these, nickel, cobalt, manganese, iron, phosphorus, and lithium are rare and valuable metals, and the recovery and recycling processes for these discarded lithium secondary batteries are emerging as important research areas.

[0003] The process of recovering these used batteries typically involves dismantling, discharging, crushing, and heat-treating the batteries to recover valuable metals. However, the process of crushing batteries carries the risk of fire and explosion, and various methods have been proposed to reduce this risk.

[0004] One of the various methods described above is to discharge the battery to nullify its electrical energy. The method for discharging the battery involves performing a brine discharge. During this process, elements such as Na, K, Mg, Ca, and Cl introduced are included as impurities in the recovered raw material, which reduces the recovery rate of valuable metals. Furthermore, the recovered material through the heat treatment process can be a black powder in the form of a mixture of valuable metal compounds, lithium compounds such as lithium carbonate, lithium aluminate, and lithium fluoride, and carbon from the negative electrode material.

[0005] At this time, when the battery is discharged, lithium ions in the negative electrode move to the positive electrode. The lithium ions that move to the positive electrode exist in the form of lithium oxide. If the electric discharge is not performed, a relatively large amount of lithium ions remain in the negative electrode, and the lithium may exist in the form of lithium carbonate or lithium fluoride.

[0006] Among the lithium compounds, lithium carbonate and lithium fluoride are water-soluble and readily leached into water, while lithium oxide in the positive electrode is readily leached into sulfuric acid. Accordingly, if the lithium in the battery is secured in a structure that facilitates leaching into water, it may be possible to recover lithium through water leaching.

[0007] Accordingly, interest is growing in battery processing methods that can ensure stability and simultaneously increase the recovery rate of valuable metals.

[0008] The technical problem to be solved by the present invention is to provide battery shredder having a high content of valuable metals while ensuring stability when introduced into a post-process.

[0009] Another technical problem to be solved by the present invention is to provide a battery processing method that ensures stability while simultaneously providing a high recovery rate of valuable metals.

[0010] According to one embodiment of the present invention, the battery shredder is a battery shredder for recovering valuable metals from a waste battery, and includes a positive electrode, a negative electrode disposed on the positive electrode, and a separator disposed between the positive electrode and the negative electrode, and the negative electrode may include fluorine (F) having a content of 5.0 to 15.0 wt% based on 100 wt% of the total negative electrode.

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

[0012] <Formula 1>

[0013] 0.25 ≤ [Li] / [F] ≤ 1.00

[0014] (In the above formula 1, [Li] and [F] represent the weight % of F and Cu in the negative electrode in the battery shredder, respectively)

[0015] In one embodiment, the cathode may have a peak comprising at least one of XRD peak values ​​of 37.5 to 39.5°, 43 to 47°, 63.5 to 67.5°, 76.8 to 80.8°, and 81 to 85°. In one embodiment, the battery shredder may satisfy the following equation 2.

[0016] <Formula 2>

[0017] 0.6 ≤ [first peak intensity] / [second peak intensity] ≤ 1.0

[0018] (In the above formula 2, [first peak intensity] and [second peak intensity] mean peak intensities in the ranges of 37.5 to 39.5 ° and 43.0 to 47.0 ° of the cathode, respectively)

[0019] In one embodiment, the negative electrode comprises a lithium compound, and the lithium compound may comprise lithium fluoride. In one embodiment, the battery shredder may satisfy the following equation 3.

[0020] <Formula 3>

[0021] [F] / [Cu] ≤ 30

[0022] (In the above formula 3, [F] and [Cu] represent the weight % of F and Cu in the negative electrode in the battery shredder, respectively)

[0023] In one embodiment, the battery shredder may have a layered structure including a separator laminated on at least one surface of the positive electrode or the negative electrode. In one embodiment, the content of fluorine in the negative electrode may be 1.0 to 12.0 wt% based on 100 wt% of the negative electrode. In one embodiment, the content of lithium in the negative electrode may be 1.0 to 5.0 wt% based on 100 wt% of the negative electrode.

[0024] In another embodiment of the present invention, a battery processing method may include the steps of preparing a battery having a voltage of 2.0 to 3.7 V, freezing the battery, and crushing the battery. In one embodiment, the step of preparing the battery includes the step of discharging the battery, and the step of discharging the battery may include the step of applying a current of 5 A or less. In another embodiment, the step of discharging the battery may be performed for 4 to 8 hours.

[0025] In one embodiment, the step of freezing the battery may cool the battery to a temperature of -150° C. to -20° C. In one embodiment, the step of freezing the battery may be performed for 15 to 36 hours.

[0026] In one embodiment, the battery shredder processed through the step of shredding the battery comprises a negative electrode, and the negative electrode may have a fluorine (F) content of 5.0 to 15.0 wt% based on 100 wt% of the total negative electrode. In one embodiment, the battery shredder may satisfy the following equation 1.

[0027] <Formula 1>

[0028] 0.25 ≤ [Li] / [F] ≤ 1.00

[0029] (In the above formula 1, [Li] and [F] represent the weight % of F and Cu in the negative electrode in the battery shredder, respectively)

[0030] According to one embodiment of the present invention, the battery shredder contains a high fluorine content, and thus is safe and has a high content of lithium compounds that are easy to apply to water leaching, and thus provides a battery shredder that increases the recovery rate of valuable metals.

[0031] According to another embodiment of the present invention, a battery treatment method provides a method for obtaining battery waste having a high content of lithium compounds that are easy to leach by performing a low-temperature treatment and crushing process according to the SOC state while leaving lithium in the negative electrode of the battery without discharging it.

[0032] FIGS. 1A and 1B are photographs of battery shreds according to one embodiment of the present invention.

[0033] FIG. 2a and FIG. 2b are XRD analysis results for the negative electrode material in the crushed material of the examples and comparative examples according to one embodiment of the present invention.

[0034] Figures 3a to 3c show the results of SEM-EDS analysis of a negative electrode material according to one embodiment of the present invention.

[0035] 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.

[0036] 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.

[0037] 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.

[0038] 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.

[0039] 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.

[0040] According to one embodiment of the present invention, battery shredder is used to recover valuable metals from waste batteries, and may include a cathode, a cathode disposed on the cathode, and a separator disposed between the cathode and the anode. Specifically, the battery shredder may have a layered structure. More specifically, the battery shredder may have a layered structure composed of a plurality of layers, and the number of layers of the layered structure may correspond to the number of separators.

[0041] The above layered structure may include, for example, anode-separator-cathode or cathode-separator-anode. For example, anode-separator-cathode-separator-anode-separator-cathode may have a three-layered layered structure. Specifically, the battery shredder may have a predetermined thickness in the thickness direction as at least one or more layers are laminated.

[0042] In one embodiment, the battery shredder may satisfy the following condition 1.

[0043] Condition 1

[0044] The above layered structure may be a laminated structure having 1 or more layers and 7 or fewer layers.

[0045] The above-mentioned 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.

[0046] In one embodiment, the battery shredder may satisfy the following condition 2.

[0047] Condition 2

[0048] The size of the above battery shreds may be 100 mm or less based on the longest axis among the length, width, and height directions.

[0049] In one embodiment, the battery shredder may have a size of 100 mm or less based on its longitudinal axis. Specifically, the size of the battery shredder may be 50 mm or less. If the size of the battery shredder is excessively large, there is a high possibility that the temperature of the battery shredder itself may rise above 100°C, which may cause a fire.

[0050] In one embodiment, the battery shredder may satisfy the following equation 1.

[0051] <Formula 1>

[0052] 0.25 ≤ [Li] / [F] ≤ 1.00

[0053] (In the above formula 1, [Li] and [F] represent the weight percentages of Li and F in the negative electrode in the battery shredder, respectively)

[0054]

[0055] The above formula 1 is a ratio of the contents of Li and F in the negative electrode among the battery shreds, and can be a qualitative indicator for the amount of lithium fluoride formed in the lithium compound. The above formula 1 can satisfy 0.25 to 1.00, specifically, 0.57 to 1.00, more specifically, 0.60 to 0.80, and even more specifically, 0.60 to 0.65. When the above formula 1 satisfies the above-mentioned range, lithium and fluorine in the negative electrode can easily form a compound, and lithium fluoride (LiF) can remain in the negative electrode, so that lithium fluoride can be easily separated from the negative electrode by water leaching in a subsequent process, thereby increasing the recovery rate of lithium.

[0056] If the above equation 1 is outside the upper limit of the aforementioned range, it means that the proportion of lithium fluoride in the lithium compound is small. If the above equation 1 is outside the lower limit of the aforementioned range, there is a problem that fluorine cannot form lithium fluoride due to a lack of lithium and instead forms other substances, and among these, in the case of HF gas, there is a problem that it causes corrosion of equipment.

[0057] In one embodiment, the negative electrode may include a lithium compound, and the lithium compound may include lithium fluoride. When the lithium fluoride stabilizes the battery by forcibly discharging the spent battery, lithium ions may migrate to the positive electrode within the battery and be formed within the positive electrode. In the method for processing the battery shredded material of the present invention, the step of freezing the battery while maintaining the voltage within the battery within a predetermined range is performed so that lithium does not migrate to the positive electrode but remains within the negative electrode, and thus the lithium fluoride may be included in the negative electrode rather than the positive electrode.

[0058] Since the lithium fluoride is contained in the cathode, rather than the anode, of the battery shredder, it can be easily separated by water leaching in a post-process. Since the lithium fluoride is contained in the cathode, it has the advantage of being easily separated by water leaching without a complex process.

[0059] In one embodiment, the negative electrode may have a peak including at least one of XRD peak values ​​of 37.5 to 39.5°, 43 to 47°, 63.5 to 67.5°, 76.8 to 80.8°, and 81.0 to 85.0°. The negative electrode may have the aforementioned peak values ​​by including lithium fluoride as the lithium compound.

[0060] In one embodiment, the battery shredder may satisfy the following equation 2.

[0061] <Formula 2>

[0062] 0.6 ≤ [first peak intensity] / [second peak intensity] ≤ 1.0

[0063] (In the above formula 2, [first peak intensity] and [second peak intensity] mean peak intensities in the ranges of 37.5 to 39.5° and 43 to 47° of the cathode, respectively)

[0064] The above equation 2 is a peak intensity ratio of lithium fluoride in the negative electrode among battery shreds, and can be an indicator for determining whether lithium fluoride remains in the negative electrode depending on whether the battery is discharged. The above equation 2 can satisfy 0.6 to 1.0. Specifically, the above equation 2 can satisfy 0.7 to 0.9.

[0065] Since the above formula 2 satisfies the aforementioned 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.

[0066] In one embodiment, the battery shredder may satisfy Equation 3 below.

[0067] <Formula 3>

[0068] [F] / [Cu] ≤ 30

[0069] (In the above formula 3, [F] and [Cu] represent the weight % of F and Cu in the negative electrode in the battery shredder, respectively)

[0070] The above formula 3 is a ratio of the content of fluorine to copper in the negative electrode among the battery shreds, and can be an indicator for checking whether lithium fluoride remains in the negative electrode depending on whether the battery has been discharged. The above formula 3 can satisfy 30 or less, specifically 20 or less, more specifically 10 or less, and even more specifically 2 to 8. Since the above formula 3 satisfies the above-mentioned range, lithium fluoride in the negative electrode among the battery shreds is appropriately contained, 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.

[0071] In one embodiment, the content of fluorine in the negative electrode may be 1.0 to 12.0 wt% based on 100 wt%. Specifically, the content of fluorine may be 2.0 to 8.5 wt%, specifically, 2.3 to 6.0 wt%, and more specifically, 3.0 to 5.5 wt%. By satisfying the above-described range of fluorine content in the negative electrode, a lithium compound such as lithium fluoride is appropriately formed in the negative electrode, and the lithium compound can be easily separated in a post-process, thereby increasing the recovery rate of lithium.

[0072] In one embodiment, the content of lithium in the negative electrode may be 1.0 to 5.0 wt% based on 100 wt%. Specifically, the content of lithium may be 1.3 to 4.3 wt%, specifically, 2.0 to 3.5 wt%. By satisfying the above-described range of fluorine content in the negative electrode, 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, thereby increasing the recovery rate of lithium.

[0073] The above-mentioned negative electrode can form lithium compounds such as lithium fluoride by simultaneously containing lithium and fluorine. If the fluorine content is excessively high, other fluoride substances such as HF may be generated in addition to lithium fluoride. If the lithium and fluorine content is excessively low, there is a problem of reduced yield.

[0074] According to another embodiment of the present invention, a battery treatment method may include the steps of preparing a battery, freezing the battery, and crushing the battery. Specifically, the battery treatment method of the present invention may be a battery treatment method in which a battery having a predetermined voltage is frozen and then crushed so that lithium ions move to the positive electrode during a separate discharge process, so that lithium fluoride is formed on the negative electrode rather than the positive electrode, and the lithium fluoride is easily separated by a method such as water leaching in a post-process.

[0075] The step of preparing a battery may be a step of preparing a battery having a voltage of 3.0 to 4.5 V. 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. The battery may have a voltage of about 4.2 to 4.5 V under a 100% SOC condition.

[0076] The step of preparing the above battery may include a step of controlling a battery having a voltage of 3.0 to 4.5 V to a voltage of 1.5 to 3.7 V. Specifically, the battery of the present invention may be controlled to have a voltage of 1.5 to 3.7 V. Specifically, the voltage may be 2.0 to 3.7 V. Since the battery has a voltage in the above-described range, it has the advantage of being able to be stably crushed through cryogenic treatment.

[0077] If the battery has a voltage higher than the aforementioned range, even after cryogenic treatment, there is a risk of fire occurring during or after crushing. If the battery has a voltage lower than the aforementioned range, the lithium fluoride content in the negative electrode is excessively low, resulting in a reduced lithium recovery rate.

[0078] The step of preparing the battery may include a step of discharging the battery, and the step of discharging the battery may include a step of applying a current of 5 A or less. Specifically, the current may be controlled to 3 A or less, more specifically, 2 A or less. By controlling the voltage of the battery within the above current range, there is an advantage in that it is easy to control the degree of rebound, in which the voltage rises again after discharging the battery. If the battery is discharged within a current range higher than the above current range, the degree of rebound increases, which may make it difficult to stabilize the battery.

[0079] In one embodiment, the step of discharging the battery may be performed for 4 to 8 hours. Specifically, the step of discharging the battery may be performed for 5 to 7 hours. The step of discharging the battery may be performed for the aforementioned time period, such that the battery is slowly discharged as the battery is discharged within the aforementioned current range. As the battery is discharged within the aforementioned range, the degree of rebound after discharge of the battery is reduced, which has the advantage of facilitating battery stabilization.

[0080] In one embodiment, 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 range of, for example, -150 to -20°C. More specifically, the temperature range may be -100 to -20°C, and even more specifically, -90 to -40°C.

[0081] 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.

[0082] If the above freezing process is performed outside the above temperature range, the voltage remaining inside the battery may not be reduced to 0 V, which may result in a battery reaction due to a short circuit, and the electrolyte may not be completely frozen, which is not appropriate. 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.

[0083] In one embodiment, the step of freezing the battery may be performed for 10 to 36 hours. The step of freezing the battery may be performed for 12 to 30 hours, specifically, 12 to 24 hours. By performing the step of freezing the battery within the aforementioned time range, battery stabilization can be facilitated, thereby preventing a fire from occurring from the battery when the battery is shredded.

[0084] If the step of freezing the battery takes excessively longer than the above time, there is a problem of inefficiency. If the step of freezing the battery is performed for excessively shorter than the above time, there is a problem of difficulty in stabilizing the battery.

[0085] 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.

[0086] 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.

[0087] 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.

[0088] 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 -90 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.

[0089]

[0090] 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.

[0091]

[0092] <Experimental Example>

[0093] <Example 1>

[0094] Battery preparation stage

[0095] When the SOC is 100%, an NCM622 lithium ion battery having approximately 4.2 V was prepared. Thereafter, a step of measuring the voltage of the battery was performed, and at this time, the battery was initially discharged to 1.0 V within 1 hour by applying a current of 5 A, and the extent of rebound over 24 hours was checked, thereby preparing a battery having a final voltage of 3.7 V and an SOC of 50%.

[0096] At this time, by controlling the current within the above range, it was confirmed that the battery rebounded to 2.5 V when discharged to 0 V, but when discharged to 10 A, which is 6 A or more, there was a problem that the battery was discharged to 0 V within 3 hours and then rebounded to 3 V. Accordingly, in Example 1, a step of slowly discharging the battery at a low current was performed.

[0097]

[0098] Cryogenic treatment stage

[0099] The above battery was subjected to cryogenic treatment at -60°C for 24 hours.

[0100]

[0101] Steps to shred the battery

[0102] The battery subjected to the above cryogenic treatment was shredded into particles of 5 to 80 mm in a particle size range using a two-axis, two-stage shredder.

[0103] FIGS. 1A and 1B are photographs of battery shreds according to one embodiment of the present invention.

[0104] Referring to FIGS. 1A and 1B, it can be confirmed that the battery shredder according to one embodiment of the present invention has a layered structure of the positive electrode, negative electrode, and separator, and the size of the shredder is 100 mm or less.

[0105]

[0106] <Example 2>

[0107] In the step of measuring the voltage of the above battery, the same procedure as Example 1 was performed, except that the battery was prepared by applying a current of 3 A and discharging it within 1 hour so that the voltage became 2.0 V.

[0108]

[0109] <Comparative Example 1>

[0110] In the battery preparation step, a current of 5 A was applied to the 3.5 V battery to perform an electric discharge, and the discharge was controlled to have a final voltage of 0.5 V or less by discharging to 0 V within 2 hours, and the same procedure as Example 1 was performed except that a separate cryogenic treatment step was not performed.

[0111]

[0112] Table 1 below shows the results of component analysis of the negative electrode material in the shredded material according to battery voltage. The battery voltage and component analysis of the negative electrode material were measured using the following methods.

[0113] Battery voltage (V): The battery voltage in Table 1 below represents the voltage of the battery after the initial battery voltage has been discharged and rebounded. The battery voltage was measured by contacting the + and - poles of the battery to the terminals using a voltage measuring device.

[0114] Component analysis: The cathode material in the crushed material was extracted through particle size screening, and the lithium (Li) component in the cathode material was analyzed using an ICP (Inductively Coupled Plasma) device. The fluorine (F) component was measured using Dionex's combustion ion chromatography, and the carbon (C) component was analyzed using a LECO C / S device.

[0115] Analysis value of components in the negative electrode material among the battery shredders [wt%] Voltage [V] LiCF Formula 1 Comparative example 10.5 or less 0.8 9 8.6 0.5 1.60 Example 13.7 2.9 9 2.5 4.6 0.63 Example 22.0 1.3 9 6.4 2.3 0.57 Formula 1: Li [wt%] / F [wt%]

[0116] Looking at Table 1 above, Comparative Example 1, which performed electric discharge, confirmed that the lithium component was mostly located in the positive electrode sample, so it had a low lithium content, and the remaining fluorine that formed a compound with the lithium also had a low value. In contrast, the shredded product of Example 1, which performed zero-discharge cryogenic treatment on a relatively high-voltage battery, was measured to have high lithium and fluorine contents in the negative electrode material.

[0117] It was confirmed that the battery having a lower voltage than Example 1 had a lithium content and fluorine content in the negative electrode material of the shredded material that were higher than those of Comparative Example 1, but lower than those of Example 1. This means that a battery having a high voltage has relatively more lithium ions located on the negative electrode side, and the lithium located on the negative electrode easily reacts with the surrounding fluorine to form lithium fluoride and remains, so the negative electrode material in the shredded material of Example 1, which has a high battery voltage, has a higher lithium and fluorine content than the negative electrode material in the shredded material of Example 2, which has a low battery voltage.

[0118] In addition, for batteries having a voltage higher than that of Example 1, for example, a voltage of 4.0 V, it was confirmed that battery treatment was not appropriate because there was a problem of fire occurring during the crushing process even when low-temperature treatment was performed.

[0119] FIG. 2a and FIG. 2b are XRD analysis results for the negative electrode material in the crushed material of the examples and comparative examples according to one embodiment of the present invention.

[0120] Figures 2a and 2b are graphs showing XRD analysis performed on the negative electrode material extracted from the shredded materials of Example 1 and Comparative Example 1, respectively. The XRD analysis measured the intensity of diffraction at each angle using an X-ray diffraction analyzer from RIGAKU.

[0121] Referring back to Fig. 2a, when electric discharge was performed, lithium was excessively transferred to the positive electrode material among the battery fragments during the discharge process, so only substances such as C or Cu were detected in the negative electrode material, and the peak values ​​of lithium and fluorine were not confirmed.

[0122] Referring back to Figure 2b, when a 3.5 V battery was subjected to cryogenic zero-discharge treatment, it was confirmed that the cathode material within the shredded material contained not only C but also LiF peaks. This was because lithium and fluorine remaining within the cathode material due to non-discharge were retained within the cathode material during the cryogenic treatment.

[0123] Table 2 below shows peak values ​​according to the XRD peak value of the negative electrode material according to one embodiment of the present invention.

[0124] DistinctionLiF formula 2First peak [cps]Second peak [cps]Third peak [cps]First peak / Second peakComparative example 1----Example 116131.533641.27133.920.48Example 28007.532298.14615.990.25First peak: Peak intensity at 37.5 to 39.5 °Second peak: Peak intensity at 43.0 to 47.0 °Third peak: Peak intensity at 63.5 to 67.5 °

[0125] Looking at Table 2 above, it was confirmed that Comparative Example 1 did not show a LiF peak. Examples 1 and 2 showed that a LiF peak occurred in the negative electrode material, and it was confirmed that Equation 2 was included in the scope of the present invention. This means that a battery with a high voltage has relatively more lithium ions located on the negative electrode side, and since the lithium located on the negative electrode easily reacts with the surrounding fluorine to form lithium fluoride and remains, it was confirmed that a LiF peak was confirmed in Examples 1 and 2, which had a high battery voltage, and the ratio of the second peak to the first peak satisfied the scope of the present invention. FIGS. 3A to 3C show the results of SEM-EDS analysis of a negative electrode material according to one embodiment of the present invention.

[0126] Figures 3a to 3c are SEM-EDS analysis results of Comparative Example 1, Example 1, and Example 2 of the present invention, respectively.

[0127] Table 3 below shows the results of SEM-EDS analysis of a negative electrode material according to one embodiment of the present invention.

[0128] The SEM-EDM of the above cathode material was measured using a SEM-EDS device from JEOL.

[0129] C[wt%]O[wt%]F[wt%]Cu[wt%]Al[wt%]P[wt%]Mn[wt%]Co[wt%]Ni[wt%]Formula 3Comparative Example 183.178.464.320.830.730.84--0.3332.0Example 177.678.8810.870.340.391.420.170.060.185.2Example 282.628.616.430.840.740.100.170.140.347.7Formula 3: F[wt%] / Cu[wt%]

[0130] Looking at Figures 3a and 3b and Table 3, in the case of Comparative Example 1, it can be confirmed that lithium moved to the positive electrode during the forced discharge process, resulting in a low fluorine content. In contrast, in Examples 1 and 2, as lithium remained in the negative electrode, lithium and fluorine reacted within the negative electrode to form lithium fluoride, resulting in a high fluorine content. Accordingly, the lithium fluoride of the Examples was formed in excess, which can increase the recovery rate of valuable metals through water leaching in a post-process.

[0131] 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, anode; A cathode disposed on the anode; Including a separator disposed between the positive electrode and the negative electrode, The above cathode is a battery shredder containing fluorine (F) in an amount of 5.0 to 15.0 wt% based on 100 wt% of the entire cathode.

2. In paragraph 1, Battery shreds satisfying the following equation 1. <Formula 1> 0.25 ≤ [Li] / [F] ≤ 1.00 (In the above formula 1, [Li] and [F] represent the weight % of F and Cu in the negative electrode in the battery shredder, respectively) 3. In paragraph 1, The above cathode is a battery shredder having a peak including at least one of XRD peak values ​​of 37.5 to 39.5°, 43 to 47°, 63.5 to 67.5°, 76.8 to 80.8°, and 81 to 85°.

4. In paragraph 1, Battery shreds satisfying the following equation 2. <Formula 2> 0.6 ≤ [First peak intensity] / [Second peak intensity] ≤ 1.0 (In the above formula 2, [first peak intensity] and [second peak intensity] mean peak intensities in the ranges of 37.5 to 39.5 ° and 43.0 to 47.0 ° of the cathode, respectively) 5. In paragraph 1, The above negative electrode contains a lithium compound, The above lithium compound is a battery waste containing lithium fluoride.

6. In paragraph 1, Battery shreds satisfying the following equation 3. <Formula 3> [F] / [Cu] ≤ 30 (In the above formula 3, [F] and [Cu] represent the weight % of F and Cu in the negative electrode in the battery shredder, respectively) 7. In paragraph 1, A battery shredder having a layered structure including a separator in which the positive electrode or the negative electrode is laminated on at least one surface.

8. In paragraph 1, A battery shredder having a fluorine content in the cathode of 1.0 to 12.0 wt% based on 100 wt% of the cathode.

9. In paragraph 1, A battery scrap having a lithium content in the negative electrode of 1.0 to 5.0 wt% based on 100 wt% of the negative electrode. A step of preparing a battery having a voltage of 3.0 to 4.5 V; a step of freezing the above battery; and Comprising the step of crushing the above battery, A battery processing method, wherein the step of preparing the battery includes a step of controlling a battery having a voltage of 3.0 to 4.5 V to a voltage of 1.5 to 3.7 V.

11. In Article 10, The step of preparing the battery includes the step of discharging the battery, A method for processing a battery, wherein the step of discharging the battery includes a step of applying a current of 5 A or less.

12. In paragraph 11, A battery treatment method wherein the step of discharging the battery is performed for 4 to 8 hours.

13. In paragraph 10, A battery processing method in which the step of freezing the battery cools the battery to -150°C to -20°C.

14. In paragraph 10, A battery treatment method wherein the step of freezing the battery is performed for 15 to 36 hours.

15. In paragraph 10, The battery shreds processed through the above step of shredding the battery contain the negative electrode, A battery treatment method wherein the cathode has a fluorine (F) content of 5.0 to 15.0 wt% based on 100 wt% of the entire cathode.

16. In paragraph 15, The above battery shredder is a battery processing method that satisfies the following equation 1. <Formula 1> 0.25 ≤ [Li] / [F] ≤ 1.00 (In the above formula 1, [Li] and [F] represent the weight % of F and Cu in the negative electrode in the battery shredder, respectively)

Images