Battery processing method

Abstract

A battery processing method for efficiently recovering lithium from a lithium ion battery. A battery processing method for processing a lithium ion battery (1) comprising a positive electrode material (31), a negative electrode material (35), and an electrolyte (39), the positive electrode material (31) and the negative electrode material (35) being stacked in a stacking direction (A), the battery processing method comprising a lithium deposition step (S2), lithium is deposited in the negative electrode material (35) by charging the lithium ion battery (1) so that the pressing force in the lamination direction (A) is greater than the remaining portions (3b, 3c) in a center portion (3a) in a plane perpendicular to the lamination direction (A) of the lithium ion battery (1).

Description

Technical Field

[0001] This invention relates to a battery processing method and a battery processing system. Background Technology

[0002] In recent years, the use of lithium-ion batteries as onboard batteries for electric vehicles, including electric cars and hybrid vehicles, has been expanding. Lithium-ion batteries contain valuable lithium-containing materials. There is a need for the recycling of these valuable materials from decommissioned lithium-ion batteries, thus promoting resource recycling.

[0003] Patent document 1 discloses a method for recovering lithium from a cathode material after increasing the amount of lithium contained in the cathode material by discharging a used lithium-ion battery.

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2022-049831

[0006] The technical problem that the invention aims to solve

[0007] Cathode materials are generally constructed by forming a positive electrode active material using current-collecting foils such as aluminum. In the case of a ternary (NMC) system, the positive electrode active material contains valuable substances such as nickel, manganese, and cobalt. To recover these valuable substances from the positive electrode active material, the material is calcined and pulverized together with a reducing agent, and then the black matter containing the positive electrode active material is screened. Next, the black matter is extracted in stages using solvent extraction, followed by the sequential extraction of manganese, cobalt, and nickel, and finally lithium. Therefore, lithium recovery, in particular, requires considerable effort. Summary of the Invention

[0008] The present invention addresses the technical problem of providing a battery processing method and battery processing system capable of effectively recovering lithium from lithium-ion batteries.

[0009] Technical means for solving technical problems

[0010] One aspect of the present invention is to provide a battery processing method for processing a lithium-ion battery comprising a positive electrode material, a negative electrode material, and an electrolyte, wherein the positive electrode material and the negative electrode material are stacked along a stacking direction, wherein the method includes a lithium deposition step, wherein the lithium-ion battery is charged by increasing the pressing pressure in the stacking direction at the central portion of the lithium-ion battery in a plane perpendicular to the stacking direction compared to the remaining portion, and lithium is deposited on the negative electrode material.

[0011] Another aspect of the present invention is to provide a battery processing system comprising: a charging device for charging a lithium-ion battery comprising a positive electrode material and a negative electrode material stacked in a stacking direction; and a pressing device for pressing the lithium-ion battery such that the pressing force in the stacking direction is increased at the central portion of the lithium-ion battery in a plane perpendicular to the stacking direction compared to the remaining portion.

[0012] Invention Effects

[0013] According to the present invention, lithium can be efficiently recovered from the negative electrode of a lithium-ion battery. Attached Figure Description

[0014] Figure 1 This is a block diagram schematically illustrating the reuse system involved in this embodiment.

[0015] Figure 2 This is a three-dimensional diagram showing the general structure of a lithium-ion battery.

[0016] Figure 3 It is a cross-sectional view showing the general structure of a single battery cell.

[0017] Figure 4 This is a diagram showing the general structure of the pressing device.

[0018] Figure 5 This is a flowchart that roughly represents the process of reusing lithium-ion batteries.

[0019] Symbol Explanation

[0020] 1 Lithium-ion battery, 3 Battery cell, 4 Battery module, 10 Recycling unit, 12 Charging device, 20 Recycling unit, 21 Disassembly device, 22 Extraction device, 23 Recycling device, 31 Positive electrode material, 34 Separator, 35 Negative electrode material, 38 Stacked electrode body, 39 Electrolyte, 40 Housing, 100 Recycling system, 301 Pressing device. Detailed Implementation

[0021] To efficiently recover lithium from lithium-ion batteries, the inventors conducted in-depth research and discovered that intentionally inducing undesirable lithium deposition (e.g., dendrites) in the negative electrode material during the normal charging reaction enables efficient lithium recovery from lithium-ion batteries. Based on this insight, the inventors have completed a battery processing method capable of efficiently recovering lithium from lithium-ion batteries.

[0022] One embodiment of the present invention relates to a method for reusing a lithium-ion battery, which processes a lithium-ion battery comprising a positive electrode material, a negative electrode material, and an electrolyte, wherein the positive electrode material and the negative electrode material are stacked along a stacking direction. The method includes a lithium deposition process in which the lithium-ion battery is charged in such a way that the central portion of the lithium-ion battery in a plane perpendicular to the stacking direction is increased in pressure toward the stacking direction compared to the remaining portion, and lithium is deposited on the negative electrode material.

[0023] Hereinafter, the lithium-ion battery recycling system according to this embodiment will be described with reference to the accompanying drawings. Figure 1 This is a schematic block diagram illustrating a lithium-ion battery 1 recycling system 100. (See diagram for example.) Figure 1 As shown, the reuse system 100 has a reuse unit 10 and a recycling unit 20. The reuse unit reuses, for example, a lithium-ion battery 1 that has been used once in an electric vehicle, and the recycling unit 20 recovers lithium from the reused lithium-ion battery 1. That is, the reuse system 100 is a battery processing system that reuses the lithium-ion battery 1 and then recovers lithium from it; in other words, it is a battery processing system for processing the lithium-ion battery 1.

[0024] The reuse unit 10 reuses the primary lithium-ion battery 1 as an energy storage device. Generally, the state of degradation of lithium-ion batteries used in electric vehicles is determined based on their State of Health (SOH), which indicates their capacity at full charge compared to when they were new. If the lithium-ion battery 1 is deemed unsuitable for use in an electric vehicle based on its degree of degradation, it is removed from the vehicle and used in the reuse unit 10 as an energy storage device for various secondary uses, such as storing renewable energy sources like solar and wind power, or as a backup power source during disasters. For example, a battery may be deemed unsuitable for primary use in an electric vehicle if its SOH is below 70%.

[0025] The reuse unit 10 includes a lithium-ion battery 1 for secondary use as an energy storage device, a charging device 12, and a pressing device 301. The charging device 12 adjusts the voltage and current and is configured to charge the lithium-ion battery 1 in any charging mode. For example, it can continuously charge the lithium-ion battery 1 with a specified voltage and current, and it can intermittently charge with a specified voltage and current (also known as pulse charging). The upper limit of the charging voltage of the charging device 12 is below the withstand voltage of the lithium-ion battery 1, for example, below 4.3V. The pressing device 301 will be described in detail after the structure of the lithium-ion battery 1 has been explained.

[0026] The recycling unit 20 includes a dismantling device 21, an extraction device 22, and a recycling device 23. For example, if it is determined, based on the State of Hypoxia (SOH), that the lithium-ion battery 1 cannot be properly utilized even in the aforementioned secondary use, the dismantling device 21 dismantles the lithium-ion battery 1 into positive electrode material 31 and negative electrode material 35, etc., through a lithium deposition process described later. The extraction device 22 extracts lithium from the dismantled negative electrode material 35, and the recycling device 23 recovers the extracted lithium. For example, it can be determined that the battery cannot be properly utilized even in secondary use if the SOH is below 40%.

[0027] Figure 2 This diagram schematically illustrates a lithium-ion battery 1 installed in an electric vehicle. The lithium-ion battery 1 includes battery modules 4 that incorporate charging and discharging circuits, cooling mechanisms, and other functions, and forms a battery pack consisting of multiple battery modules 4 interconnected and housed within a casing. Each battery module 4 is composed of multiple individual battery cells 3 connected in parallel or series, and is adjusted to the desired capacity and voltage.

[0028] Lithium-ion battery 1 is a rechargeable lithium-ion secondary battery. In this manual, unless otherwise specified, the term lithium-ion battery is sometimes used collectively to refer to battery cell, battery module, and battery pack.

[0029] Figure 3 This is a schematic cross-sectional view of battery cell 3. (e.g.) Figure 3 As shown, the battery cell 3 involved in this embodiment is a laminated type. The battery cell 3 has a laminated electrode body 38 and a housing 40. The laminated electrode body 38 is formed by laminating a positive electrode material 31, a separator 34 and a negative electrode material 35 in this order in the lamination direction A. The housing 40 houses the laminated electrode body 38.

[0030] In this embodiment, the stacked electrode body 38 is composed of multiple sets of positive electrode material 31, separator 34 and negative electrode material 35 stacked in the stacking direction A. When viewed from the stacking direction A, the battery cell 3 has a slender rectangular shape in the width direction B.

[0031] The positive electrode material 31 has a positive current collector 32 and a positive active material 33 disposed on the surface of the positive current collector 32 facing the separator 34. The plurality of positive current collectors 32 have one end in the width direction B orthogonal to the stacking direction (in... Figure 3 The positive electrode current collector 32a (left side, center) is connected to the positive electrode. The positive electrode current collector 32 can preferably be made of a metal foil suitable for the positive electrode. The positive electrode active material 33 can be a material used as the positive electrode active material in lithium-ion secondary batteries. In this embodiment, the positive electrode current collector 32 is made of aluminum, and the positive electrode active material 33 is made of NMC (nickel, manganese, cobalt).

[0032] The negative electrode material 35 has a negative electrode current collector 36 and a negative electrode active material 37 disposed on the surface of the negative electrode current collector 36 facing the separator 34. The plurality of negative electrode current collectors 36 have another end in the width direction B (in... Figure 3 The negative electrode current collector ends 36a (right side in the middle) are interconnected. The negative electrode current collector 36 can preferably be made of a metal foil suitable for a negative electrode. The negative electrode active material 37 can be a material used as a negative electrode active material in lithium-ion secondary batteries. In this embodiment, the negative electrode current collector 36 is made of copper, and the negative electrode active material 37 is a carbon material (graphite) containing a layered structure.

[0033] Both the positive electrode active material 33 and the negative electrode active material 37 contain an electrolyte 39. The electrolyte 39 is, for example, an organic solvent in which lithium ions can move. In this embodiment, the electrolyte 39 contains dimethyl carbonate (DMC), ethylene carbonate (EC), and diethyl carbonate (DEC) in a volume ratio of 1:1:1, and contains lithium hexafluoride phosphate (LiPF6) at a concentration of 1 mol / L.

[0034] A separator 34 is disposed between the positive electrode material 31 and the negative electrode material 35, physically and electrically separating them. The separator 34 can be a porous body having multiple tiny pores that allow lithium ions to pass through. In this embodiment, the separator 34 is a porous membrane made of polyolefin.

[0035] The housing 40 has a first housing 41 and a second housing 42, which are configured as a pair, on both sides of the stacking direction A of the stacked electrode body 38. The first housing 41 and the second housing 42 are formed in a cap-shaped cross section. The first housing 41 has a pair of flange portions 41a located at both ends in the width direction B and a main body portion 41b located between the pair of flange portions 41a and bulging away from the second housing 42 in the stacking direction A. Similarly, the second housing 42 has a pair of flange portions 42a and a main body portion 42b bulging away from the first housing 41.

[0036] The first housing 41 and the second housing 42 are joined together to form the housing 40, with the positive electrode current collector 32a and the negative electrode current collector 36a sandwiched between their respective flanges 41a and 42a. That is, with the stacked electrode body 38 housed in the housing 40, the positive electrode current collector 32a and the negative electrode current collector 36a are sandwiched between a pair of flanges 41a and 42a, and the remaining portion of the stacked electrode body 38 is housed in the space defined between a pair of main body portions 41b and 42b. The stacked electrode body 38, while housed in the housing 40, is pressed together by the pair of main body portions 41b and 42b along the stacking direction A with a predetermined pressure. An example of the tab 43 of the present invention is formed by the portion of the battery cell 3 sandwiched between a pair of flanges 41a and 42a.

[0037] In this embodiment, the lithium-ion battery 1 deteriorates relatively quickly, and it is envisioned that the electrolyte 39 will be depleted, especially at the periphery 3z of the battery cell 3.

[0038] Next, the pressing device 301 will be described. The pressing device 301 is a device that presses the battery cell 3 with a predetermined pressing force along the stacking direction A. In order to generate a charge-discharge reaction in the lithium-ion battery 1, the pressing device 301 can be installed in a lithium-ion battery 1 that is used once in an electric vehicle, or it can be installed in a lithium-ion battery 1 that is reused in the recycling section 10. Alternatively, a pressing device that can automatically or manually adjust the pressing force can also be provided. There is no particular limitation on the pressing device 301, and any actuator such as a hydraulic cylinder or a pneumatic cylinder can be used.

[0039] Figure 4 This is a schematic diagram showing the pressing device 301. Figure 4 The image briefly shows the battery cell 3 pressed by the pressing device 301. For example... Figure 4 As shown, the pressing device 301 has multiple sets of pressing member pairs 302 divided in the width direction B of the battery cell 3, and each set of pressing member pairs 302 is arranged in pairs on both sides of the stacking direction A of the battery cell 3. In this embodiment, the pressing device 301 has a central pressing member pair 302A located in the center of the width direction B, and a pressing member pair 302A located on one side of the width direction B (in the middle of the stacking direction A). Figure 4 The pressing member on one side (left side) is 302B, and the other side (located in the width direction B) is also 302B. Figure 4 The other side of the pressing element pair 302C (middle is the right side). The pressing element pair 302 is not limited to three sets, and can also be divided into two or more sets. In addition, as Figure 4 As shown, the electrode portion located in the area enclosed by the dashed line and the side of the battery cell 3 is the central portion 3a, and the electrode portions outside this area are the remaining portions, namely the two side portions 3b and 3c.

[0040] Next, the reuse of lithium-ion battery 1 will be explained. Figure 5 This is a flowchart that roughly illustrates the process of reusing lithium-ion battery 1. For example... Figure 5 As shown, when the lithium-ion battery 1 installed in an electric vehicle is determined to be in a deteriorated state unsuitable for use in an electric vehicle based on, for example, the state of harmlessness (SOH), a recycling process (step S1) is performed. In the recycling process S1, the lithium-ion battery 1 is removed from the electric vehicle for reuse in the recycling unit 10.

[0041] After the lithium-ion battery 1 is supplied for secondary use and used as an energy storage device, if it is determined to be in a specified deterioration state, a lithium deposition process (step S2) is performed in the recycling unit 10 after secondary use. In the lithium deposition process S2, the lithium-ion battery 1 is pressed along the stacking direction A under specified pressing conditions while being charged.

[0042] In the lithium deposition process S2, the battery cell 3 is locally pressed by activating at least a portion of the multiple sets of pressing pairs 302. Specifically, as follows: Figure 4 As shown, only the central pressing member 302A of the multiple pressing members 302, located at the center of the width direction B and / or height direction C of the battery cell 3, is activated, thereby pressing only the central portion 3a of the battery cell 3 in the width direction B. Therefore, in the lithium deposition process S2, the pressing is performed such that the central portion 3a of the battery cell 3 in the plane perpendicular to the stacking direction A has a greater pressing force in the stacking direction A compared to the remaining portions 3b and 3c.

[0043] For example, if the pressing member pair 302 is configured to be divided into four approximately equally along the width direction B, only the two inner pressing member pairs 302 along the width direction B may be activated. Similarly, if the pressing member pair 302 is configured to be divided into five approximately equally along the width direction B, only the three inner pressing member pairs 302 along the width direction B may be activated, or only the central pressing member pair 302 along the width direction B may be activated. That is, in the lithium deposition process S2, the portion including the central portion 3a of the battery cell 3 but excluding the peripheral portion 3z may be pressed.

[0044] Generally, in order to generate a charge-discharge reaction within the lithium-ion battery 1, it is necessary to press (i.e., constrain) the battery cells 3 along the stacking direction. In the lithium deposition process S2, the battery cells 3 are pressed at least with a pressing force sufficient to generate this charge-discharge reaction. For example, this pressing force is 10 kPa or more but less than 1 MPa.

[0045] "Increasing the pressing pressure in the stacking direction A in the central portion 3a compared to the remaining portions 3b and 3c" also means reducing the pressing pressure at the remaining portions 3b and 3c while the battery cell 3 is being uniformly pressed as a whole. For example, in a lithium-ion battery 1 that is being reused in the recycling section 10, i.e., where the entire battery is being uniformly pressed, the lithium deposition process S2 includes reducing or releasing the pressing pressure on the remaining portions 3b and 3c. In this way, when the lithium deposition process S2 is performed using a pressing device provided on the lithium-ion battery 1 being reused, compared to performing the lithium deposition process S2 by separately installing a pressing device on the lithium-ion battery 1, no installation effort is required, and the operation can be performed efficiently.

[0046] In the lithium deposition process S2, the lithium-ion battery 1 is charged while the central portion 3a of the battery cell 3 is partially pressed by the pressing device 301, so that lithium is deposited from the negative electrode material 35.

[0047] In this embodiment, the lithium-ion battery 1 is charged using a high-rate charging method, thereby causing lithium to be deposited in the negative electrode material 35. High-rate charging refers to charging with a large current in a manner that intentionally causes lithium to be generated in the negative electrode material 35.

[0048] For example, in the case of a lithium-ion battery 1 installed in an electric vehicle, specifically a capacity-type (also called an energy-type) battery, it is preferable to charge it with a current of, for example, 2C or higher. Furthermore, in the case of a lithium-ion battery 1 installed in a hybrid electric vehicle, specifically a high-output type (also called a power-type) battery, it is preferable to charge it with a current of, for example, 10C or higher. Here, 1C refers to the current required to fully charge each lithium-ion battery in one hour. Additionally, the aforementioned high-rate charging refers to charging with a current of, or greater than, the current required to fully charge the lithium-ion battery in two hours. By continuously charging at a high rate for a specified time, lithium can be deposited on the negative electrode material 35.

[0049] In this specification, "capacity type" for lithium-ion battery 1 refers to a capacity of 600 Wh / L or higher. "High output type" for lithium-ion battery 1 refers to a capacity of 4000 kW / L or higher.

[0050] When the charging current at a high charging rate is too large, the electrolyte 39 may vaporize due to heat, resulting in undesirable side reactions such as deformation and damage to various components. From an energy-saving perspective, excessive charging current is also undesirable. For example, when the lithium-ion battery 1 is a capacity-type battery, it is preferable to set the upper limit of the charging current to around 3C. On the other hand, when the lithium-ion battery 1 is an output-type battery, it is preferable to set the upper limit of the charging current to around 20C.

[0051] Furthermore, when charging the lithium-ion battery 1, increasing the pressing pressure on the central portion 3a promotes (concentrated) charging reactions at the negative electrode material 35 corresponding to the central portion 3a. Moreover, at the two side portions 3b and 3c of the battery cell 3, electrolyte depletion easily occurs, causing it to escape outwards from the peripheral portion 3z. On the other hand, at the central portion 3a, since it is far from the peripheral portion 3z, electrolyte 39 easily remains. Therefore, by increasing the pressing pressure at the central portion 3a where electrolyte 39 easily remains, lithium is effectively deposited at the negative electrode material 35 corresponding to the central portion 3a. As a result, the charging current is concentrated at the location where electrolyte 39 remains and the charging reaction is promoted, thus enabling localized high-rate charging and facilitating localized lithium deposition.

[0052] Here, in the lithium deposition process S2, the lithium-ion battery 1 can be charged as long as it is in a pressed state. The pressing process of the pressing device 301 on the lithium-ion battery 1 and the charging process of the charging device 12 on the lithium-ion battery 1 can start simultaneously, or either one can start first. That is, the charging process of the charging device 12 can be performed after the pressing process of the pressing device 301 is performed, while maintaining the pressing state of the pressing device 301.

[0053] Next, the lithium-ion battery 1 is removed from the recycling section 10, and a battery dismantling process (step S3) is performed on the lithium-ion battery 1 using the dismantling device 21. In the battery dismantling process S3, the lithium-ion battery 1 is dismantled into components such as a positive electrode material 31, a separator 34, a negative electrode material 35, and a casing 40. Furthermore, if only lithium is intended for recycling, at least the negative electrode material 35 can be dismantled. The dismantling device 21 can be any device that automatically dismantles the lithium-ion battery 1. Alternatively, the lithium-ion battery 1 can be manually dismantled using tools or the like without using the dismantling device 21.

[0054] Next, a lithium extraction process (step S4) is performed. In lithium extraction step S4, lithium is extracted from the disassembled negative electrode material 35. In lithium extraction step S4, the negative electrode material 35 is permeated with water by the extraction device 22 and then filtered, thereby removing the negative electrode current collector 36 and the negative electrode active material 37 from the negative electrode material 35 and extracting an aqueous solution containing lithium ions. Furthermore, in lithium extraction step S4, lithium is selectively extracted from the portion of the negative electrode material 35 corresponding to the central portion 3a where lithium was partially deposited in the aforementioned lithium deposition step S2. It can be determined visually which portion of the multiple disassembled negative electrode materials 35 corresponds to the central portion 3a, or it can be determined based on the portion pressed by the pressing device 301 (i.e., the central portion 3a). This allows for more efficient lithium extraction.

[0055] Finally, a lithium recovery process (step S5) is performed. In lithium recovery step S5, lithium is recovered from an aqueous solution containing lithium ions. In lithium recovery step S5, lithium is soluble in carbonated water by recovery device 23 and then filtered, thereby recovering lithium as lithium carbonate.

[0056] In the above embodiment, the pressing member pair 302 is described as being divided along the width direction B of the battery cell 3. However, it can also be divided along the height direction C, which is orthogonal to the stacking direction A and the width direction B of the battery cell 3. Furthermore, it can be divided along both the width direction B and the height direction C.

[0057] That is, the battery processing method involved in this embodiment is a battery processing method for processing a lithium-ion battery 1 comprising a positive electrode material 31, a negative electrode material 35 and an electrolyte 39, wherein the positive electrode material 31 and the negative electrode material 35 are stacked along the stacking direction A. The lithium deposition process S2 is to charge the lithium-ion battery 1 by increasing the pressing pressure in the stacking direction A at the central portion 3a in the plane perpendicular to the stacking direction A compared to the remaining portions 3b and 3c, thereby depositing lithium on the negative electrode material 35.

[0058] As a result, the negative electrode material 35 is generally constructed by layering graphite onto current collector foil such as copper, and therefore contains fewer valuable substances compared to the positive electrode material 31, which contains multiple valuable substances such as cobalt, nickel, and manganese. Therefore, unlike the staged extraction of multiple valuable metals required when recovering lithium from the positive electrode material 31, lithium can be effectively recovered from the negative electrode material 35. Furthermore, by increasing the pressing pressure in the central portion 3a of the lithium-ion battery 1, where electrolyte 39 tends to remain, lithium is more easily deposited locally in the portion of the negative electrode material 35 corresponding to the central portion 3a. As a result, lithium can be recovered more effectively.

[0059] In the lithium deposition process S2, charging is performed using a high-rate charging method. As a result, by utilizing the high-rate charging, lithium can be intentionally deposited onto the negative electrode material 35.

[0060] In the lithium extraction step S4, lithium is selectively extracted from a portion of the negative electrode material 35 corresponding to the central portion 3a. As a result, lithium can be extracted more efficiently.

[0061] The lithium-ion battery 1 recycling system 100 disclosed herein is not limited to the configuration described in the above embodiments and can be modified in various ways.

[0062] In the above embodiments, a laminated type lithium-ion battery was described as an example, but it is not limited to this. For example, as a lithium-ion battery, a cylindrical or square type can also be used, which is formed by stacking strip-shaped positive electrode material, strip-shaped separator, and strip-shaped negative electrode material in the stacking direction A to form a strip-shaped laminated electrode body and then winding it into a cylindrical or square shape. In the case of cylindrical and square types, the stacking direction corresponds to the radial direction orthogonal to the winding direction.

[0063] Although described on a single-unit basis, it can also be implemented on a module-by-module or battery pack-by-pack basis. In the case of implementation on a battery pack-by-pack basis, a pressing device can be pre-installed within the battery pack.

[0064] In the lithium deposition process S2, charging can also be performed without a high charging rate. That is, if the lithium-ion battery 1 is a capacity-type battery, it can be charged with a current of less than 2C, for example. Alternatively, if the lithium-ion battery 1 is a high-output type battery, it can be charged with a current of less than 10C, for example.

Claims

1. A battery processing method for processing a lithium-ion battery comprising a positive electrode material, a negative electrode material, and an electrolyte, wherein the positive electrode material and the negative electrode material are stacked along a stacking direction, characterized in that, The process includes a lithium deposition step, in which the lithium-ion battery is charged by increasing the pressing pressure in the stacking direction at the center of the plane perpendicular to the stacking direction compared to the remaining portion, thereby depositing lithium on the negative electrode material.

2. The battery processing method according to claim 1, characterized in that, In the lithium deposition process, charging is performed using a high-rate charging method.

3. The battery processing method according to claim 1 or 2, characterized in that, The battery processing method further includes: The battery dismantling process, following the lithium deposition process, involves dismantling at least the negative electrode material from the lithium-ion battery; and The lithium extraction process involves extracting lithium from the negative electrode material.

4. The battery processing method according to claim 3, characterized in that, In the lithium extraction process, lithium is selectively extracted from a portion of the negative electrode material corresponding to the central portion.

5. The battery processing method according to claim 1, characterized in that, In the lithium deposition process, the lithium-ion battery is pressed along the stacking direction using a pressing device. The pressing device has multiple sets of pressing member pairs divided in the width direction of the lithium-ion battery, and each set of pressing member pairs is arranged in pairs on both sides of the stacking direction of the lithium-ion battery. In the lithium deposition process, only a portion of the multiple sets of pressing elements are activated.

6. The battery processing method according to claim 1, characterized in that, In the lithium deposition process, the lithium-ion battery is pressed along the stacking direction using a pressing device. The pressing device has multiple sets of pressing member pairs, including: a central pressing member pair located at the center of the width direction of the lithium-ion battery, a side pressing member pair located on one side of the width direction, and another side pressing member pair located on the other side of the width direction. In the lithium deposition process, at least a portion of the multiple sets of pressing elements are deactivated.

7. The battery processing method according to claim 2, characterized in that, The high-rate charging refers to charging with a current greater than that required to fully charge the lithium-ion battery in two hours.

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