Battery processing method and battery processing system

Abstract

This invention provides a battery processing method that can efficiently recover lithium from lithium-ion batteries. [Solution] A battery processing method for a lithium-ion battery having a plurality of battery cells 3 comprising a positive electrode material 31 and a negative electrode material 35, wherein the positive electrode material 31 and the negative electrode material 35 are stacked in the stacking direction A, includes a lithium deposition step of charging the lithium-ion battery by increasing the pressing force in the stacking direction A for at least a portion of it compared to the remaining portion, thereby depositing lithium on the negative electrode material 35.

Description

Technical Field

[0001] The present invention relates to a battery processing method and a battery processing system.

Background Art

[0002] In recent years, the adoption of lithium-ion batteries as in-vehicle batteries for electric vehicles such as electric vehicles and hybrid vehicles has been expanding. Lithium-ion batteries contain valuable substances containing lithium. It is required to recycle resources by recycling valuable substances from used lithium-ion batteries.

[0003] Patent Document 1 discloses a method of increasing the amount of lithium contained in a positive electrode material by discharging a used lithium-ion battery and then recovering lithium from the positive electrode material.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] The positive electrode material is generally composed of forming a positive electrode active material on a current collector foil such as aluminum. The positive electrode active material contains valuable substances such as nickel, manganese, cobalt, etc. in the case of a ternary system (NMC) for example. To recover valuable substances from the positive electrode active material, the positive electrode material is baked with a reducing agent, pulverized, and then black mass containing the positive electrode active material is sorted. Next, the black mass is subjected to solvent extraction step by step, and manganese, cobalt, and nickel are sequentially extracted, and finally lithium is extracted. For this reason, it has been particularly laborious to recover lithium.

[0006] The object of this invention is to provide a battery processing method and a battery processing system that can efficiently recover lithium from lithium-ion batteries. [Means for solving the problem]

[0007] One aspect of the present invention is, A battery processing method for processing a lithium-ion battery comprising a positive electrode material and a negative electrode material, wherein the positive electrode material and the negative electrode material are stacked in a stacking direction, A lithium deposition process is performed by charging the lithium-ion battery by increasing the pressing force in the stacking direction on at least a portion of it compared to the remaining portion, thereby depositing lithium on the negative electrode material. The present invention provides a battery processing method that includes [a specific component].

[0008] Other aspects of the present invention include: A charging device for a lithium-ion battery comprising a positive electrode material and a negative electrode material, wherein the positive electrode material and the negative electrode material are stacked in a stacking direction, A pressing device that presses at least a portion of the lithium-ion battery with an increased pressing force in the stacking direction compared to the remaining portion, We provide a battery processing system that includes the following features. [Effects of the Invention]

[0009] According to the present invention, lithium can be efficiently recovered from the negative electrode of a lithium-ion battery. [Brief explanation of the drawing]

[0010] [Figure 1] A schematic block diagram illustrating the reuse system according to the first embodiment. [Figure 2] A perspective view showing the schematic configuration of a lithium-ion battery. [Figure 3] A cross-sectional view showing the general configuration of a battery cell. [Figure 4] A diagram showing the schematic configuration of the pressing device. [Figure 5] A flowchart illustrating the general process of reusing lithium-ion batteries. [Modes for carrying out the invention]

[0011] The inventors have diligently conducted research to efficiently recover lithium from lithium-ion batteries and have discovered that lithium can be efficiently recovered from lithium-ion batteries by intentionally inducing lithium deposition (e.g., dendrites), which is undesirable in normal charging reactions, on the negative electrode material. Based on this finding, the inventors have completed a battery processing method that can efficiently recover lithium from lithium-ion batteries.

[0012] A method for reusing lithium-ion batteries according to one embodiment of the present invention is: A battery processing method for processing a lithium-ion battery comprising a positive electrode material and a negative electrode material, wherein the positive electrode material and the negative electrode material are stacked in a stacking direction, A lithium deposition process is performed by charging the lithium-ion battery by increasing the pressing force in the stacking direction on at least a portion of it compared to the remaining portion, thereby depositing lithium on the negative electrode material. It includes.

[0013] [First Embodiment] Hereinafter, a lithium-ion battery reuse system according to the first embodiment of the present invention will be described with reference to the attached drawings. Figure 1 is a schematic block diagram showing a lithium-ion battery reuse system 100. As shown in Figure 1, the reuse system 100 has a reuse unit 10 that reuses a lithium-ion battery 1 that has been used primarily in, for example, an electric vehicle, and a recycling unit 20 that recovers lithium from the reused lithium-ion battery 1. In other words, the reuse system 100 is a battery processing system for reusing a lithium-ion battery 1 and then recovering lithium from the lithium-ion battery 1, or in other words, for processing a lithium-ion battery 1.

[0014] The reuse section 10 reuses the once - used lithium - ion battery 1 as a power storage device. Generally, for a lithium - ion battery used in an electric vehicle, the state of deterioration is judged based on the SOH (State Of Health) which indicates how much capacity there is compared to, for example, when it is new at full charge. When the lithium - ion battery 1 is judged to be inappropriate for use in an electric vehicle based on the degree of deterioration, it is removed from the vehicle and used in the reuse section 10 as a power storage device for various secondary uses such as storing renewable energy like solar power generation and wind power generation, or as a backup power source during disasters. For example, when the SOH becomes 70% or less, it may be judged that it is not appropriate for primary use, that is, for use in an electric vehicle.

[0015] The reuse section 10 includes the lithium - ion battery 1 reused as a power storage device, a charging device 12, and a pressing device 301. The charging device 12 is configured to adjust the voltage and current so that the lithium - ion battery 1 can be charged in an arbitrary charging pattern. For example, the lithium - ion battery 1 can be continuously charged at a predetermined voltage and current, and can also be intermittently charged at a predetermined voltage and current (also called pulse charging). The upper limit of the charging voltage by the charging device 12 is below the withstand voltage of the lithium - ion battery 1, for example, 4.3V or less. The pressing device 301 will be described in detail after the structure of the lithium - ion battery 1 is explained.

[0016] When it is judged that the lithium - ion battery 1 cannot be appropriately used even in the above - mentioned secondary use, for example, based on the SOH, the recycling section 20 has a disassembling device 21 that disassembles the lithium - ion battery 1 into a positive electrode material 31, a negative electrode material 35, etc. through a lithium precipitation process described later, an extraction device 22 that extracts lithium from the disassembled negative electrode material 35, and a recovery device 23 that recovers the extracted lithium. For example, when the SOH becomes 40% or less, it may be judged that it cannot be appropriately used even in secondary use.

[0017] Figure 2 schematically shows a lithium-ion battery 1 mounted on an electric vehicle. The lithium-ion battery 1 is composed of battery modules 4 incorporating functions such as charge / discharge circuits and cooling mechanisms, and further, a plurality of battery modules 4 are connected to each other and housed in a case to form a battery pack. The battery module 4 is composed of a plurality of battery cells 3 connected in series or in parallel to each other, and is adjusted to a desired capacity and voltage.

[0018] The lithium-ion battery 1 is a rechargeable lithium-ion secondary battery. In this specification, the term "lithium-ion battery" may collectively refer to battery cells, battery modules, and battery packs unless otherwise specified.

[0019] Figure 3 is a cross-sectional view schematically showing the battery cell 3. As shown in Figure 3, the battery cell 3 according to this embodiment is a laminate type. The battery cell 3 has a laminated electrode body 38 in which a positive electrode material 31, a separator 34, and a negative electrode material 35 are laminated in the stacking direction A in this order, and a case 40 in which the laminated electrode body 38 is housed.

[0020] In this embodiment, the laminated electrode body 38 is composed of a plurality of sets of positive electrode material 31, separator 34, and negative electrode material 35 laminated in the stacking direction A. The battery cell 3 is rectangular in shape and elongated in the width direction B when viewed from the stacking direction A.

[0021] The positive electrode material 31 has a positive electrode current collector 32 and a positive electrode active material 33 disposed on the surface of the positive electrode current collector 32 facing the separator 34. The plurality of positive electrode current collectors 32 have a positive electrode current collecting end portion 32a connected to each other at one end portion (the left side in Figure 3) in the width direction B orthogonal to the stacking direction. A metal foil suitable for the positive electrode can be preferably used for the positive electrode current collector 32. As the positive electrode active material 33, a material used as a positive electrode active material of a lithium-ion secondary battery can be used. 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).

[0022] The negative electrode material 35 comprises 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. Multiple negative electrode current collectors 36 have negative electrode current collector ends 36a that are connected to each other at their other ends (right side in Figure 3) in the width direction B. A metal foil suitable for a negative electrode can preferably be used for the negative electrode current collector 36. A material used as a negative electrode active material for lithium-ion secondary batteries can be used for the negative electrode active material 37. 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) with a layered structure.

[0023] 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 on 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 lithium hexafluoride phosphate (LiPF6) at a concentration of 1 mol / L.

[0024] The separator 34 is positioned between the positive electrode material 31 and the negative electrode material 35, physically and electrically separating them. The separator 34 may be a porous material having multiple minute pores through which lithium ions can pass. In this embodiment, the separator 34 is a porous membrane made of polyolefin.

[0025] Case 40 has a pair of first cases 41 and second cases 42 provided on both sides of the stacking direction A of the stacked electrode body 38. The first case 41 and the second case 42 are formed in a hat-shaped cross section. The first case 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 in a direction away from the second case 42 in the stacking direction A. Similarly, the second case 42 has a pair of flange portions 42a and a main body portion 42b bulging in a direction away from the first case 41.

[0026] Case 40 is formed by joining a first case 41 and a second case 42 with the positive electrode current collector end 32a and the negative electrode current collector end 36a sandwiched between their respective flange portions 41a and 42a. That is, with the laminated electrode body 38 housed in case 40, the positive electrode current collector end 32a and the negative electrode current collector end 36a are sandwiched between the pair of flange portions 41a and 42a, and the remaining portion of the laminated electrode body 38 is housed in the space defined between the pair of main body portions 41b and 42b. With the laminated electrode body 38 housed in case 40, it is pressed against the pair of main body portions 41b and 42b at a predetermined pressure in the stacking direction A. An example of the tab 43 according to the present invention is formed by the portion of the battery cell 3 sandwiched between the pair of flange portions 41a and 42a.

[0027] In the first embodiment, it is assumed that the lithium-ion battery 1 has not deteriorated much and that the electrolyte 39 has spread throughout the entire battery cell 3.

[0028] Next, the pressing device 301 will be described. The pressing device 301 is a device that presses the battery cell 3 in the stacking direction A with a predetermined pressing force. The pressing device 301 may be installed in the lithium-ion battery 1 that has been primarily used in an electric vehicle in order to generate a charge-discharge reaction within the lithium-ion battery 1, or it may be installed in the lithium-ion battery 1 that has been secondarily used in the reuse section 10. Alternatively, a separate pressing device that can adjust the pressing force automatically or manually may be provided. The pressing device 301 is not particularly limited, and any actuator such as a hydraulic cylinder or a pneumatic cylinder can be used.

[0029] Figure 4 is a schematic diagram of the pressing device 301. Figure 4 also schematically shows the battery cell 3 that is pressed by the pressing device 301. As shown in Figure 4, the pressing device 301 has a pair of presser pairs 302 provided on both sides of the stacking direction A of the battery cell 3, and divided in the width direction B of the battery cell 3. In this embodiment, the pressing device 301 has a central presser pair 302A located in the center of the width direction B, a side presser pair 302B located on one side of the width direction B (left side in Figure 4), and a other side presser pair 302C located on the other side of the width direction B (right side in Figure 4). The presser pairs 302 are not limited to three, but may be divided into two or four or more.

[0030] Next, the reuse of the lithium-ion battery 1 will be explained. Figure 5 is a flowchart that schematically shows the flow of reuse of the lithium-ion battery 1. As shown in Figure 5, if the lithium-ion battery 1 that was installed in the electric vehicle is determined to be in a deteriorated state that is unsuitable for use in the electric vehicle, for example based on the State of Health (SOH), a reuse process (step S1) is carried out. In reuse process S1, the lithium-ion battery 1 is removed from the electric vehicle and put to secondary use in the reuse unit 10.

[0031] When the lithium-ion battery 1 is used for secondary purposes and is determined to be in a predetermined state of degradation after being used as an energy storage device, the reuse section 10 performs a lithium deposition process (step S2) following the secondary use. In the lithium deposition process S2, the lithium-ion battery 1 is charged while being pressed in the stacking direction A under predetermined pressing conditions.

[0032] In the lithium deposition process S2, the battery cell 3 is charged while being locally pressed by activating at least some of the presser pairs 302 of the multiple presser pairs 302. Therefore, in the lithium deposition process S2, the battery cell 3 is pressed with an increased pressing force in the stacking direction A in at least a portion of it compared to the rest. Generally, in order to generate a charge-discharge reaction within the lithium-ion battery 1, it is necessary to press (i.e., restrain) the battery cell 3 in the stacking direction. In the lithium deposition process S2, the battery cell 3 is pressed with a pressing force that is at least necessary for the charge-discharge reaction to occur. For example, this pressing force is between 10 kPa and 1 MPa.

[0033] "Increasing the pressing force in the stacking direction A in at least a portion compared to the remaining portion" also means reducing the pressing force in the remaining portion when the entire battery cell 3 is being pressed evenly. For example, in a lithium-ion battery 1 that is being reused in the reuse section 10, i.e., is being pressed evenly throughout, partially reducing or releasing the pressing force is included in the lithium deposition process S2. In this way, when the lithium deposition process S2 is carried out using the pressing device provided in the lithium-ion battery 1 that has been reused, it is possible to carry out the work efficiently without the hassle of attaching a separate pressing device to the lithium-ion battery 1, compared to when the lithium deposition process S2 is carried out by attaching a separate pressing device to the lithium-ion battery 1.

[0034] In the lithium deposition process S2, the lithium-ion battery 1 is charged in such a way that lithium is deposited on the negative electrode material 35 while the battery cell 3 is locally pressed by the pressing device 301.

[0035] In this embodiment, lithium is deposited on the negative electrode material 35 by charging the lithium-ion battery 1 using high-rate charging. High-rate charging means charging with a large current that intentionally generates lithium on the negative electrode material 35 during charging.

[0036] For example, if the lithium-ion battery 1 is a so-called capacity type (also called energy type) installed in an electric vehicle, it is preferable to charge it with a current of 2C or more. Also, if the lithium-ion battery 1 is a so-called high-output type (also called power type) installed in a hybrid vehicle, it is preferable to charge it with a current of 10C or more. Here, a current of 1C means the current required to fully charge each lithium-ion battery in one hour. By continuously charging at a high rate for a predetermined period of time, lithium can be deposited on the negative electrode material 35.

[0037] In this specification, a lithium-ion battery 1 is considered to be a capacity-type battery if its energy density is 600 Wh / L or higher. Furthermore, a lithium-ion battery 1 is considered to be a high-power type battery if its power density is 4000 kW / L or higher.

[0038] If the charging current becomes excessive due to high-rate charging, undesirable side reactions may occur, such as gasification of the electrolyte 39 due to heat generation, deformation and damage to each component, and excessive charging current is undesirable from the standpoint of energy saving. For example, if the lithium-ion battery 1 is a capacity type, it is preferable to set the upper limit of the charging current to about 3C. On the other hand, if the lithium-ion battery 1 is a high-output type, it is preferable to set the upper limit of the charging current to about 20C.

[0039] Furthermore, when charging the lithium-ion battery 1, increasing the pressing force in at least a portion of the battery can accelerate (concentrate) the charging reaction in the negative electrode material 35 corresponding to that portion. As a result, the charging current is concentrated in the area where the charging reaction is accelerated, allowing for high-rate charging in that area and facilitating localized lithium deposition. For example, lithium may be deposited across the entire surface of the negative electrode material 35 by sequentially changing the location where the pressing force is increased during charging. Alternatively, lithium may be efficiently deposited in areas where electrolyte remains by increasing the pressing force in those areas.

[0040] In the lithium deposition step S2, the lithium-ion battery 1 only needs to be charged while being pressed. The pressing step of the lithium-ion battery 1 by the pressing device 301 and the charging step of the lithium-ion battery 1 by the charging device 12 may be started simultaneously, or one of them may be started first. That is, after the pressing step by the pressing device 301 is performed, the charging step by the charging device 12 may be performed while the pressing state by the pressing device 301 is maintained.

[0041] Next, the lithium-ion battery 1 is removed from the reuse section 10 and the battery dismantling process (step S3) is performed by the dismantling device 21. In the battery dismantling process S3, the lithium-ion battery 1 is dismantled into its constituent components, such as the positive electrode material 31, separator 34, negative electrode material 35, and case 40. If the intention is to recover only lithium, at least the negative electrode material 35 may be dismantled. The dismantling device 21 may be any device that automatically dismantles the lithium-ion battery 1. Alternatively, the lithium-ion battery 1 may be dismantled manually using tools or the like without using the dismantling device 21.

[0042] Next, a lithium extraction process (step S4) is performed. In lithium extraction process S4, lithium is extracted from the disassembled negative electrode material 35. In lithium extraction process S4, the negative electrode current collector 36 and negative electrode active material 37 are removed from the negative electrode material 35 by the extraction device 22, after which the negative electrode material 35 is leached with water and then filtered, and an aqueous solution containing lithium ions is extracted. In lithium extraction process S4, lithium is selectively extracted from the portion of the disassembled negative electrode material 35 in which lithium was locally deposited in the lithium deposition process S2. That is, lithium is selectively extracted from the portion of the negative electrode material 35 corresponding to the portion pressed by the pressing device 301. Which of the multiple disassembled negative electrode materials 35 corresponds to the portion can be identified by visual inspection or based on the portion pressed by the pressing device 301. This allows for more efficient extraction of lithium.

[0043] Finally, a lithium recovery process (step S5) is carried out. In lithium recovery process S5, lithium is recovered from an aqueous solution containing lithium ions. In lithium recovery process S5, the lithium is dissolved in carbonated water by the recovery device 23 and then filtered to recover lithium as lithium carbonate.

[0044] In the above embodiment, the case in which the presser pair 302 is divided in the width direction B of the battery cell 3 was described as an example, but it may also be divided in the height direction C which is perpendicular to the stacking direction A and the width direction B of the battery cell 3, or it may even be divided in both the width direction B and the height direction C.

[0045] In other words, the battery processing method according to this embodiment is A battery processing method for processing a lithium-ion battery 1 which includes a positive electrode material 31 and a negative electrode material 35, wherein the positive electrode material 31 and the negative electrode material 35 are stacked in the stacking direction A, Lithium deposition step S2: Charges the lithium-ion battery 1 by increasing the pressing force in the stacking direction A on at least a portion of it compared to the remaining portion, thereby depositing lithium on the negative electrode material 35. It includes.

[0046] As a result, since the negative electrode material 35 is generally constructed by laminating graphite in layers on a current collector foil made of, for example, copper, it contains fewer valuable substances compared to the positive electrode material 31, which contains multiple types of valuable substances such as cobalt, nickel, and manganese. Therefore, as is the case when recovering lithium from the positive electrode material 31, it is not necessary to perform the stepwise solvent extraction of multiple types of valuable metals, and lithium can be recovered efficiently from the negative electrode material 35. Furthermore, by increasing the pressing force in at least a part of the lithium-ion battery 1, lithium can be locally deposited in the negative electrode material 35 corresponding to that part. As a result, lithium can be recovered even more efficiently.

[0047] The lithium deposition step S2 includes reducing the pressing force in the remaining portion while the entire lithium-ion battery 1 is being pressed evenly. As a result, compared to the case where a separate pressing device is attached to the lithium-ion battery 1 to perform the lithium deposition process S2, this method eliminates the need for attachment and allows for more efficient work.

[0048] [Second Embodiment] The second embodiment differs in that a second lithium deposition step S12 is used instead of the lithium deposition step S2 according to the first embodiment. In the second lithium deposition step S12, the central part of the battery cell 3 in the width direction B and / or height direction C is pressed in the stacking direction A with a predetermined pressing force.

[0049] The reuse system 200 according to the second embodiment, referring to Figure 1, is equipped with a pressing device 301 similar to the reuse system 100 according to the first embodiment, and the lithium-ion battery 1 is provided to the reuse section 10 in the form of a battery cell 3.

[0050] In the second embodiment, the degradation of the lithium-ion battery 1 is more advanced compared to the lithium-ion battery 1 in the first embodiment, and it is assumed that the electrolyte 39 is depleted, particularly at the peripheral edge 3z of the battery cell 3.

[0051] In the second lithium deposition step S12, as shown in Figure 4, only the central presser pair 302A, located in the center of the battery cell 3 in the width direction B and / or height direction C, is activated from among the multiple presser pairs 302, thereby pressing only the central part 3a in the width direction B of the battery cell 3. Therefore, in the second lithium deposition step S12, the battery cell 3 is charged by increasing the pressing force toward the central part 3a in the plane perpendicular to the stacking direction A compared to the remaining parts 3b and 3c.

[0052] As a result, in the battery cell 3, electrolyte tends to escape outward from the peripheral edge 3z at both sides 3b and 3c, leading to depletion of electrolyte, while in the central part 3a, electrolyte 39 tends to remain because it is separated from the peripheral edge 3z. Therefore, by increasing the pressing force in the central part 3a where electrolyte 39 tends to remain, lithium can be efficiently deposited on the negative electrode material 35 corresponding to the central part 3a.

[0053] The lithium-ion battery reuse systems 100 and 200 relating to this disclosure are not limited to the configurations described in the above embodiments, and various modifications are possible.

[0054] In the above embodiment, a laminated lithium-ion battery was described as an example, but it is not limited to this. For example, a cylindrical or rectangular lithium-ion battery may be used, which is constructed by winding a strip-shaped laminated electrode body, in which a strip-shaped positive electrode material, a strip-shaped separator, and a strip-shaped negative electrode material are stacked in the stacking direction A, into a cylindrical or rectangular shape. In the case of cylindrical and rectangular types, the stacking direction corresponds to the radial direction perpendicular to the winding direction.

[0055] Although the explanation was given on a cell-by-cell basis, it can also be done on a module-by-module or battery pack-by-battery basis. If done on a battery pack basis, a pressing device may be pre-installed inside the battery pack.

[0056] In the lithium deposition step S2, charging at a high rate is not required. That is, if the lithium-ion battery 1 is a capacity type, it may be charged with a current of less than 2C, for example. Also, if the lithium-ion battery 1 is a high-power type, it may be charged with a current of less than 10C, for example.

[0057] [Note] According to the lithium-ion battery reuse system 100,200 relating to this disclosure, the following aspects are provided.

[0058] [Aspect 1] A battery processing method for processing a lithium-ion battery comprising a positive electrode material and a negative electrode material, wherein the positive electrode material and the negative electrode material are stacked in a stacking direction, A lithium deposition process is performed by charging the lithium-ion battery by increasing the pressing force in the stacking direction on at least a portion of it compared to the remaining portion, thereby depositing lithium on the negative electrode material. A battery processing method, including the following.

[0059] [Aspect 2] The lithium deposition step includes reducing the pressing force in the remaining portion while the entire lithium-ion battery is being pressed evenly. The battery processing method described in Embodiment 1.

[0060] [Aspect 3] The lithium-ion battery further contains an electrolyte, In the lithium deposition step, the lithium-ion battery is charged by increasing the pressing force in the stacking direction on the central portion in a plane perpendicular to the stacking direction compared to the remaining portion. The battery processing method according to embodiment 1 or 2.

[0061] [Aspect 4] The aforementioned battery processing method is: Following the lithium deposition step, a battery dismantling step is performed, in which at least the negative electrode material is dismantled from the lithium-ion battery. A lithium extraction step for extracting lithium from the negative electrode material, A battery processing method according to any one of embodiments 1 to 3, further comprising the above.

[0062] [Aspect 5] A charging device for a lithium-ion battery comprising a positive electrode material and a negative electrode material, wherein the positive electrode material and the negative electrode material are stacked in a stacking direction, A pressing device that presses at least a portion of the lithium-ion battery with an increased pressing force in the stacking direction compared to the remaining portion, A battery processing system equipped with the following features. [Explanation of Symbols]

[0063] 1. Lithium-ion battery 3 battery cells 4 Battery Modules 10. Reuse Department 12 Charging device 20 Recycling Department 21 Demolition equipment 22 Extraction device 23 Recovery device 31 Cathode material 34 Separator 35. Negative electrode material 38. Stacked electrode body 39 Electrolyte 40 cases 100 Reuse Systems 301 Pressing device

Claims

1. A battery processing method for processing a lithium-ion battery comprising a positive electrode material and a negative electrode material, wherein the positive electrode material and the negative electrode material are stacked in a stacking direction, A lithium deposition process is performed by charging the lithium-ion battery by increasing the pressing force in the stacking direction on at least a portion of it compared to the remaining portion, thereby depositing lithium on the negative electrode material. A battery processing method, including the following.

2. The lithium deposition step includes reducing the pressing force in the remaining portion while the entire lithium-ion battery is being pressed evenly. The battery processing method according to claim 1.

3. The lithium-ion battery further contains an electrolyte, In the lithium deposition step, the lithium-ion battery is charged by increasing the pressing force in the stacking direction on the central portion in a plane perpendicular to the stacking direction compared to the remaining portion. The battery processing method according to claim 1 or 2.

4. The aforementioned battery processing method is: Following the lithium deposition step, a battery dismantling step is performed, in which at least the negative electrode material is dismantled from the lithium-ion battery. A lithium extraction step for extracting lithium from the negative electrode material, The battery processing method according to claim 1, further comprising:

5. A charging device for a lithium-ion battery comprising a positive electrode material and a negative electrode material, wherein the positive electrode material and the negative electrode material are stacked in a stacking direction, A pressing device that presses at least a portion of the lithium-ion battery with an increased pressing force in the stacking direction compared to the remaining portion, A battery processing system equipped with the following features.

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