Battery processing method and battery processing system

Abstract

The present invention provides a battery processing method and a battery processing system 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, each containing 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 in the stacking direction A, the method comprising: a gas generation step of generating gas within the lithium-ion battery; and 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

[0006] ,

[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 cars 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 recovering lithium from a positive electrode material after increasing the amount of lithium contained in the positive electrode material by discharging a used lithium-ion battery.

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 a current collector foil such as aluminum and a positive electrode active material formed thereon. 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 roasted 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. Therefore, 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, a negative electrode material, and an electrolyte, wherein the positive electrode material and the negative electrode material are stacked in a stacking direction, A gas generation step for generating gas within the lithium-ion battery, A lithium deposition step is performed to charge 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, a negative electrode material, and an electrolyte, wherein the positive electrode material and the negative electrode material are stacked in a stacking direction, A gas generator for generating gas within the lithium-ion battery, 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] Figure showing the schematic configuration of the pressing device. [Figure 5] Flowchart schematically showing the flow of lithium-ion battery reuse. [Figure 6] Figure schematically showing an example of the operation of the pressing device. [Figure 7] Block diagram schematically showing the reuse system according to the second and third embodiments. [Figure 8] Figure schematically showing an example of the operation of the heating device and the pressing device according to the second embodiment. [Figure 9A] Figure schematically showing an example of the operation of the heating device and the pressing device according to the third embodiment. [Figure 9B] Figure schematically showing an example of the operation of the pressing device following Figure 9A.

Embodiments for Carrying Out the Invention

[0011] The inventors of the present invention have conducted intensive research to efficiently recover lithium from lithium-ion batteries, and have found that lithium precipitation (for example, dendrites), which is not desirable in normal charging reactions, can be intentionally caused on the negative electrode material to efficiently recover lithium from the lithium-ion battery. Based on this finding, the inventors of the present invention have completed a battery treatment method capable of efficiently recovering lithium from a lithium-ion battery.

[0012] A method for reusing a lithium-ion battery according to an embodiment of the present invention is a battery treatment method for treating a lithium-ion battery including a positive electrode material, a negative electrode material, and an electrolyte, wherein the positive electrode material and the negative electrode material are laminated in a stacking direction, and a gas generation step of generating gas in the lithium-ion battery, and a lithium precipitation step of charging the lithium-ion battery by increasing the pressing force in the stacking direction of at least a part compared to the remaining part to precipitate lithium on the negative electrode material and includes.

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

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

[0015] 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 is configured to adjust the voltage and current to charge the lithium-ion battery 1 in any charging pattern. For example, the lithium-ion battery 1 can be continuously charged at a predetermined voltage and current, or 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 less than or equal to 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 described.

[0016] The recycling unit 20 includes a dismantling device 21 that dismantles the lithium-ion battery 1 into positive electrode material 31 and negative electrode material 35, etc., through a lithium deposition process described later, if it is determined that the lithium-ion battery 1 cannot be properly reused even in the above secondary reuse, for example, based on SOH; an extraction device 22 that extracts lithium from the dismantled negative electrode material 35; and a recovery device 23 that recovers the extracted lithium. For example, it may be determined that the battery cannot be properly reused even in secondary reuse if the SOH is 40% or less.

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

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

[0019] Figure 3 is a schematic cross-sectional view of the battery cell 3. As shown in Figure 3, the battery cell 3 according to this embodiment is of the laminated 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 stacked in this order in the stacking direction A, and a case 40 in which the laminated electrode body 38 is housed.

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

[0021] The positive electrode material 31 comprises 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. Multiple positive electrode current collectors 32 have positive electrode current collector ends 32a that are connected to each other at one end (left side in Figure 3) in the width direction B perpendicular to the stacking direction. Suitable metal foils for positive electrodes can be preferably used for the positive electrode current collector 32. Materials used as positive electrode active materials for lithium-ion secondary batteries can be used for the positive electrode active material 33. 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] Next, the pressing device 301 will be described. The pressing device 301 is a device that presses the battery cells 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 was first 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 was 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.

[0028] 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.

[0029] 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.

[0030] 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 unit 10 performs a gas generation process (step S2) to generate gas within the battery cell 3, following the secondary use.

[0031] In the gas generation process S2, the entire battery cell 3 is pressed in the stacking direction A with a predetermined pressing force from the pressing device 301 and charged with an excessive charging current by the charging device 12. The predetermined pressing force in the gas generation process S2 is a pressure sufficient to cause a charge-discharge reaction during the primary or secondary use of the lithium-ion battery 1. The current flowing in the gas generation process S2 is higher than the upper limit current in the lithium deposition process S3, which will be described below. The excessive current flowing throughout the battery cell 3 generates heat inside the battery cell 3, and gas is generated from the electrolyte 39 prior to the lithium ion reduction reaction (i.e., lithium deposition reaction). Therefore, in the first embodiment, the charging device 12 is also a gas generator. The gas generated in the gas generation process S2 is, for example, methane and / or carbon dioxide.

[0032] Next, the lithium deposition process (step S3) is performed. In the lithium deposition process S3, the lithium-ion battery 1 is charged while being pressed in the stacking direction A under predetermined pressing conditions. In the lithium deposition process S3, the battery cells 3 are locally pressed by activating at least some of the pressing pairs 302 of a plurality of pressing pairs 302. Therefore, in the lithium deposition process S3, the battery cells 3 are pressed with an increased pressing force in the stacking direction A in at least a portion of the battery cells compared to the remaining portion. 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 cells 3 in the stacking direction. In the lithium deposition process S3, the battery cells 3 are pressed with a pressing force that is at least necessary for the charge-discharge reaction to occur. For example, this pressing force is 10 kPa or more and 1 MPa or less.

[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. In other words, reducing or releasing the pressing force in a portion of the battery cell 3 from the state in which the entire battery cell 3 is being pressed in the gas generation step S2 is included in the lithium deposition step S3.

[0034] In the lithium deposition process S3, 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] As shown in Figure 6, the battery cell 3 contains the gas generated by the gas generation process S2 throughout its entire interior, and is further pressed only at the other end 3c (right side in Figure 6) by the pressing device 301. Generally, when gas is generated inside the battery cell 3, the movement of electrons between the positive electrode material 31 and the negative electrode material 35 is inhibited by the gas, making it difficult for charge and discharge reactions to occur. Under these circumstances, if charging is performed by pressing only a part of the battery cell 3 (the other end 3c in Figure 6), the charge reaction is more easily promoted (concentrated) in that part compared to the remaining part (the central part 3a and one end 3b in Figure 6). As a result, the charging current is concentrated in the area where the charge reaction is promoted, making it easier to deposit lithium locally.

[0036] 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.

[0037] 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.

[0038] In this specification, a lithium-ion battery 1 is considered a capacity-type battery if its energy density is 600 Wh / L or higher. Furthermore, a lithium-ion battery 1 is considered a high-power type battery if its power density is 4000 kW / L or higher.

[0039] As described above, if the charging current due to high-rate charging becomes excessive, heat generation will cause gasification of the electrolyte 39, making lithium deposition difficult. For this reason, excessive charging current is undesirable in the lithium deposition step S3. 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. Therefore, in the gas generation step S2 described above, a current higher than 3C may flow if the lithium-ion battery 1 is a capacity type, and a current higher than 20C may flow if the lithium-ion battery 1 is a high-output type.

[0040] In the lithium deposition step S3, 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 S4) is performed by the dismantling device 21. In the battery dismantling process S4, 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.

[0042] Next, a lithium extraction process (step S5) is performed. In lithium extraction process S5, lithium is extracted from the disassembled negative electrode material 35. In lithium extraction process S5, 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 S5, 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 S3. 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 disassembled negative electrode material 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 S6) is carried out. In lithium recovery process S6, lithium is recovered from an aqueous solution containing lithium ions. In lithium recovery process S6, 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 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 in the stacking direction A, A gas generation step S2 generates gas inside the lithium-ion battery 1, A lithium deposition step S3 is performed in which the lithium-ion battery 1 is charged by increasing the pressing force in the stacking direction A in at least a portion of it compared to the remaining portion, thereby depositing lithium on the negative electrode material 35. 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 stepwise solvent extraction of multiple types of valuable metals, and lithium can be recovered efficiently from the negative electrode material 35. Furthermore, by generating gas inside the lithium-ion battery 1 and 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] In the lithium extraction step S5, lithium is selectively extracted from the portion of the negative electrode material 35 that corresponds to at least a part of the material that was pressed in the lithium deposition step S3. As a result, lithium can be extracted even more efficiently.

[0048] [Second Embodiment] The second embodiment differs in that a second gas generation step S12 is used instead of the gas generation step S2 according to the first embodiment. In the second gas generation step S12, the entire battery cell 3 is heated by the heating device 401, thereby generating gas inside the battery cell 3.

[0049] The reuse system 200 according to the second embodiment further includes a heating device 401, with reference to Figure 7. The heating device 401 can be any device capable of heating the surface of the battery cell 3 to 80°C. For example, the heating device 401 is a Peltier element. As shown in Figure 8, the heating device 401 is arranged on pairs of pressers 302 provided on both sides of the stacking direction A of the battery cell 3.

[0050] In the second gas generation step S12, as shown in Figure 8, the entire battery cell 3 is heated by the heating device 401 while being pressed in the stacking direction A with a predetermined pressing force from the pressing device 301. In the second gas generation step S12, the battery cell 3 is not charged with at least an excessive charging current. As the entire battery cell 3 is heated, gas similar to that in the first embodiment is generated from the electrolyte 39 inside the battery cell 3. Therefore, in the second gas generation step S12, gas is generated by heating the entire battery cell 3.

[0051] As a result, compared to the case where the battery cell 3 is charged with an excessive charging current to generate gas, it is possible to suppress other undesirable side reactions within the battery cell 3 and reduce power consumption in the gas generation process.

[0052] [Third Embodiment] The third embodiment differs in that a third gas generation step S13 is used instead of the gas generation step S2 in the first embodiment. The reuse system 300 in the third embodiment, referring to Figure 7, is equipped with a heating device 401, similar to the second embodiment.

[0053] As shown in Figure 9A, the heating device 401 of the third embodiment is located only between the central presser pair 302A and the one-sided presser pair 302B. In the third gas generation step S13, a portion of the battery cell 3 is heated by the heating device 401, causing gas to be generated in a portion of the battery cell 3.

[0054] In the third gas generation step S13, as shown in Figure 9A, the entire battery cell 3 is pressed in the stacking direction A with a predetermined pressing force from the pressing device 301, and only the central part 3a and one end 3b of the battery cell 3 are heated by the heating device 401. Therefore, gas is generated in the central part 3a and one end 3b. Also, since the other end 3c, which is not heated, is pressed, the generated gas does not easily flow to the other end 3c.

[0055] Next, in the lithium deposition step S3, as shown in Figure 9B, only the other end 3c where no gas is generated is pressed. In other words, according to the third embodiment, gas is partially generated within the battery cell 3 by heating the remaining portion of the battery cell 3 that is not pressed in the lithium deposition step S3, or that is pressed with a lower pressure than the portion where lithium is locally deposited.

[0056] As a result, since no gas is generated in the compressed area, the charging reaction is further accelerated. This allows for more efficient recovery of lithium.

[0057] The lithium-ion battery reuse systems 100 to 300 relating to this disclosure are not limited to the configurations described in the above embodiments, and various modifications are possible.

[0058] 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.

[0059] 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.

[0060] In the lithium deposition step S3, 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. [Explanation of symbols]

[0061] 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 Positive electrode material 34 Separator 35. Negative electrode material 38. Stacked electrode body 39 Electrolyte 40 cases 100 Reuse Systems 301 Pressing device 401 Heating device

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 in a stacking direction, A gas generation step for generating gas within the lithium-ion battery, A lithium deposition step is performed to charge 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. In the gas generation step, the gas is generated by heating the entire lithium-ion battery. The battery processing method according to claim 1.

3. In the gas generation step, the gas is partially generated within the lithium-ion battery by heating at least the remaining portion. The battery processing method according to claim 1.

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 claims 1 to 3, further comprising the above.

5. In the lithium extraction step, lithium is selectively extracted from the portion of the negative electrode material corresponding to at least a part that was pressed in the lithium deposition step. The battery processing method according to claim 4.

6. A charging device for 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 in a stacking direction, A gas generator for generating gas within the lithium-ion battery, 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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