Method for dismantling a laminated structure

Abstract

The present invention provides a method for dismantling laminates that suppresses the generation of waste liquid and improves the peelability of the laminate. [Solution] The method for dismantling a laminate involves bringing water into contact with a laminate having a conductor and layers laminated on the conductor, applying an electrical pulse in a gas between a pair of electrodes in contact with the laminate, and peeling the layers from the conductor. This method for dismantling a laminate suppresses the generation of waste liquid and improves the peelability of the laminate.

Description

[Technical Field]

[0001] The present invention relates to a method for dismantling a laminate. [Background technology]

[0002] In recent years, there has been a growing importance in recovering and reusing useful resources from electronic devices such as home appliances and communication terminals, as well as components used in hybrid and electric vehicles. For example, the positive electrode of a lithium-ion secondary battery is constructed as a laminate in which a positive electrode active material layer containing positive electrode active material is stacked on a positive electrode current collector, and useful resources such as nickel (Ni) and cobalt (Co) are used for the positive electrode active material. The present inventors have proposed a method for dismantling laminates such as the positive electrode of a lithium-ion secondary battery using an electrical pulse method (for example, Patent Document 1 and Non-Patent Document 1).

[0003] Patent Document 1 discloses a method for disassembling a lithium-ion secondary battery's positive electrode into a positive electrode current collector as a thin aluminum film and a positive electrode active material layer containing a positive electrode active material such as cobalt, by bringing a pair of electrodes into contact with the positive electrode and applying an electrical pulse between the pair of electrodes. The electrical pulse is applied in a gas or water.

[0004] Non-patent document 1 also discloses a method for dismantling a positive electrode into an aluminum thin film and a positive electrode active material layer by applying an electrical pulse between a pair of electrodes in a gas or water. When applying an electrical pulse in water, the positive electrode and the pair of electrodes are placed in the water, and the electrical pulse is applied between the pair of electrodes. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 2022-106024 [Non-patent literature]

[0006] [Non-Patent Document 1] Soowon Lim, et al., “Comparison of Positive Electrode Separation by Electrical Pulsed Discharge in Underwater and Air Environments”, IEEE TRANSACTIONS ON PLASMA SCIENCE, Vol. 50, No. 10, pp.3625 - 3634, 2022 [Overview of the project] [Problems that the invention aims to solve]

[0007] However, applying electrical pulses in a gaseous environment did not yield a sufficient peeling effect, and applying electrical pulses in water resulted in a high peeling effect but also the problem of generating a large amount of waste liquid.

[0008] Therefore, the present invention aims to provide a method for dismantling a laminate that can suppress the generation of waste liquid and improve the peelability of the laminate. [Means for solving the problem]

[0009] The method for dismantling a laminate according to the present invention involves bringing water into contact with a laminate having a conductor and layers laminated on the conductor, applying an electrical pulse in a gas between a pair of electrodes in contact with the laminate, and peeling the layers from the conductor. [Effects of the Invention]

[0010] According to the present invention, by bringing water into contact with the laminate and applying an electric pulse in a gas, the generation of waste liquid can be suppressed and the peelability of the laminate can be improved. [Brief explanation of the drawing]

[0011] [Figure 1] This is a schematic diagram of the laminate. [Figure 2] This is a flowchart explaining how to dismantle a laminated structure. [Figure 3] It is an explanatory diagram for explaining the liquid contact process. [Figure 4] It is an explanatory diagram for explaining the electrode contact process. [Figure 5] It is an explanatory diagram for explaining the electrode contact process. [Figure 6A] It is a photograph showing the surface of Example 1 after applying an electric pulse. [Figure 6B] It is a photograph showing the back surface of Example 1 after applying an electric pulse.

Mode for Carrying Out the Invention

[0012] 1. Embodiment Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

[0013] The laminate used in the method for disassembling the laminate according to this embodiment is the positive electrode of a lithium-ion secondary battery. The configuration of the positive electrode as the laminate will be described.

[0014] FIG. 1 is a schematic diagram of the positive electrode 1 as a laminate. As shown in FIG. 1, the positive electrode 1 has a positive electrode current collector 11 and a positive electrode active material layer 12 laminated on the positive electrode current collector 11. The positive electrode 1 has a configuration in which the positive electrode active material layer 12 is provided on both surfaces of the positive electrode current collector 11. Note that the positive electrode 1 is not limited to the configuration in which the positive electrode active material layer 12 is provided on both surfaces of the positive electrode current collector 11, and may have a configuration in which the positive electrode active material layer 12 is provided on only one surface of the positive electrode current collector 11. The positive electrode 1 is an example of the laminate. The positive electrode current collector 11 is an example of the conductor constituting the laminate. The positive electrode active material layer 12 is an example of the layer constituting the laminate.

[0015] The positive electrode current collector 11 is a foil containing aluminum (hereinafter also referred to as Al foil). The positive electrode active material layer 12 has a positive electrode active material, a binder, and a conductive auxiliary material. The binder is polyvinylidene fluoride (PVDF) or the like. The conductive auxiliary material is a carbon material such as graphite or carbon black.

[0016] The positive electrode active material is selected from lithium nickel composite oxide, lithium cobalt composite oxide, lithium manganese composite oxide, lithium iron phosphate, lithium nickel cobalt composite oxide, lithium nickel manganese composite oxide, lithium cobalt manganese composite oxide, lithium nickel cobalt manganese composite oxide, any magnesium composite oxide, any sodium composite oxide, any potassium composite oxide, any calcium composite oxide, etc. In this embodiment, the positive electrode active material is lithium nickel cobalt manganese composite oxide.

[0017] Next, the method for dismantling the laminate will be described. The method for dismantling the laminate involves bringing water into contact with the laminate, which has a conductor and layers stacked on top of the conductor, and applying an electrical pulse in a gas between a pair of electrodes in contact with the laminate to separate the layers from the conductor.

[0018] Figure 2 is a flowchart illustrating the method for dismantling a laminate according to this embodiment. As shown in Figure 2, the method for dismantling a laminate includes a preparation step S10, a liquid contact step S11, an electrode contact step S12, and an electrical pulse application step S13. Each step will be described in detail below.

[0019] [Preparation process] In preparation step S10, a laminate to be used in the laminate dismantling method is prepared. In this embodiment, a positive electrode 1 taken from a lithium-ion secondary battery is prepared as the laminate. The positive electrode used as the laminate may be a positive electrode taken from a used lithium-ion secondary battery, a positive electrode taken from an unused lithium-ion secondary battery that was found to be defective after manufacturing, a positive electrode taken from process waste in the manufacturing process of a lithium-ion secondary battery, or process waste in the manufacturing process of a positive electrode, etc.

[0020] [Liquid contact process] In the liquid contact step S11, water as a liquid is brought into contact with the positive electrode 1 as a laminate. Here, the presence of the liquid increases the physical force due to the pulse power when the electrical pulse is applied in the electrical pulse application step S13 described later, improving the peelability of the laminate. The water includes pure water and ultrapure water. The method of bringing the liquid into contact with the laminate is not particularly limited and includes, for example, a method of coating the laminate with the liquid, a method of dropping the liquid onto the laminate, a method of spraying the liquid onto the laminate, and a method of immersing the laminate in the liquid (dip). A method of coating the laminate with the liquid includes a method of dropping the liquid onto the laminate and spreading the dropped liquid with a coating member such as a brush. The liquid may or may not be impregnated into the laminate. The liquid is brought into contact with at least a part of the laminate. In this embodiment, the liquid is brought into contact with the surface of the positive electrode 1 as a laminate, but not with the back surface of the positive electrode 1.

[0021] As shown in Figure 3, water is brought into contact with the liquid contact area 15 of the positive electrode 1 as a laminate. The liquid contact area 15 is a part of the positive electrode 1 as a laminate. The liquid contact area 15 is not particularly limited as long as an area for contacting the electrodes in the next step, electrode contact step S12, is secured. In this embodiment, the liquid contact area 15 is a region of the positive electrode 1 that is away from the edge of the positive electrode 1 and is set in the central part of the positive electrode 1. The area of ​​the positive electrode 1 excluding the liquid contact area 15 is the electrode contact area 16 for contacting the electrodes, which will be described later. The area ratio of the liquid contact area 15 on the surface of the positive electrode 1 as a laminate that is brought into contact with the liquid is preferably 50% or more and 100% or less, and more preferably 80% or more and 100% or less. Note that if the positive electrode active material layer 12 is provided on only one side of the positive electrode current collector 11, the liquid contact area 15 may be set on the side of the positive electrode current collector 11 that does not have the positive electrode active material layer 12.

[0022] [Electrode contact process] As shown in Figure 4, in the electrode contact step S12, a pair of electrodes are brought into contact with the positive electrode 1 as a laminate. In this embodiment, the pair of electrodes consists of positive electrodes 20a, 20b and negative electrodes 21a, 21b. One end of the positive electrode 1 is sandwiched between the positive electrodes 20a, 20b, and the other end of the positive electrode 1 is sandwiched between the negative electrodes 21a, 21b. The positive electrode 20a and the negative electrode 21a are in contact with the surface of the positive electrode 1, and the positive electrode 20b and the negative electrode 21b are in contact with the back surface of the positive electrode 1.

[0023] As shown in Figure 5, in this embodiment, a pair of electrodes, positive electrodes 20a, 20b and negative electrodes 21a, 21b, are brought into contact with an electrode contact area 16 that is different from the liquid contact area 15 of the positive electrode 1. In Figure 5, the positive electrodes 20a and negative electrodes 21a that are in contact with the surface of the positive electrode 1 are shown, while the positive electrodes 20b and negative electrodes 21b that are in contact with the back surface of the positive electrode 1 are hidden at the back of the page. The electrode contact area 16 is set as a predetermined region of the positive electrode 1 from the edge of the positive electrode 1. The electrode contact area 16 may be changed, for example, depending on the size of the positive electrodes 20a, 20b and the negative electrodes 21a, 21b.

[0024] The positive electrodes 20a, 20b and negative electrodes 21a, 21b, as a pair of electrodes, are connected to an electrical pulse generator 30 via cables 31 and 32 (see Figure 4). The electrical pulse generator 30 is used to apply electrical pulses between the pair of electrodes via cables 31 and 32. In Figure 4, the positive electrodes 20a, 20b are connected to the electrical pulse generator 30 via cable 31, and the negative electrodes 21a, 21b are connected to the electrical pulse generator 30 via cable 32.

[0025] In this embodiment, the positive electrodes 20a, 20b and negative electrodes 21a, 21b, as a pair of electrodes, are in surface contact with the positive electrode 1 as a laminate, but are not limited to this, and may be in line contact or point contact with the positive electrode 1. When bringing the pair of electrodes into contact with the laminate, the laminate may be fixed with a fixing member (not shown). For example, a block-shaped fixing member can be used to fix one end and the other end of the positive electrode 1 by sandwiching them. In this embodiment, the pair of electrodes consists of positive electrodes 20a, 20b and negative electrodes 21a, 21b that sandwich the positive electrode 1, but may also be configured not to sandwich the positive electrode 1, for example, with positive electrodes 20a and negative electrodes 21a in contact with the surface of the positive electrode 1, or with positive electrodes 20b and negative electrodes 21b in contact with the back surface of the positive electrode 1. In this embodiment, the pair of electrodes are in contact with the positive electrode active material layer 12, but are not limited to this, and may also be in contact with the positive electrode current collector 11. In this embodiment, the electrode contact area 16, where the pair of electrodes are brought into contact, is set as a different region from the liquid contact area 15, but it may also be set as a region that overlaps with the liquid contact area 15. That is, the pair of electrodes may be brought into contact with a region of the laminate where liquid is present.

[0026] [Electrical pulse application process] In the electrical pulse application step S13, an electrical pulse is applied between the pair of electrodes in a gas. When an electrical pulse is applied between the pair of electrodes from the electrical pulse generator 30, Joule heat is generated in the positive electrode current collector 11. This Joule heat causes the binder contained in the positive electrode active material layer 12 to decompose or melt. As the binder present at the interface between the positive electrode current collector 11 and the positive electrode active material layer 12 decomposes or melts, the bond between the positive electrode current collector 11 and the positive electrode active material layer 12 loosens. The physical force caused by the pulse power generated by the application of the electrical pulse acts on the interface between the positive electrode current collector 11 and the positive electrode active material layer 12, promoting separation between the positive electrode current collector 11 and the positive electrode active material layer 12, and the positive electrode active material layer 12 is peeled off from the positive electrode current collector 11. The peeled positive electrode active material layer 12 cannot maintain its layer shape and is in the form of granules or powder. Here, the physical force due to pulsed power refers to a complex force such as the rapid volume expansion of high-temperature materials caused by the plasma generated by high voltage, and the resulting shock waves. Due to the physical force due to pulsed power, granular or powdery positive electrode active material is scattered from the positive electrode current collector 11 into the surroundings. The granular or powdery positive electrode active material may remain on the positive electrode current collector 11 without scattering. The positive electrode active material remaining on the positive electrode current collector 11 can be easily brushed off using a brush or the like. By applying an electrical pulse in a gas, the positive electrode active material layer 12 is detached from the positive electrode current collector 11 in the gas, and the positive electrode active material can also be recovered in the gas. However, when an electrical pulse is applied in water, the positive electrode active material layer 12 is detached from the positive electrode current collector 11 and dispersed in the water in the form of granules or powder, making it difficult to recover the positive electrode active material. In this embodiment, applying an electrical pulse in a gas makes it easier to recover the positive electrode active material compared to applying an electrical pulse in water.

[0027] The electric pulse generator 30 uses a known or well-known device. For example, the electric pulse generator 30 includes a DC power source, a capacitor, a pair of electrodes as a load, a switching element, a voltage probe, a current probe, an external ground, etc. A method of generating pulse power using the electric pulse generator 30 will be described. First, a voltage is applied from the DC power source to the capacitor to charge the capacitor with energy. Next, the switching element is switched to supply (input) the energy charged in the capacitor to the load. An electric pulse is applied between a pair of electrodes as the load, and pulse power is generated.

[0028] Here, the electric pulse is defined by the energy density ED [J / mg]. The energy density ED is the energy input per unit weight of the Al foil as a conductor, and is obtained by the following Equation 1.

[0029] [Equation 1] ED = E Al / m Al = E C × R Al / (R Al + R C ) × 1 / m Al Here, in Equation 1 above, E Al is the energy [J] input to the Al foil, m Al is the weight [mg] of the Al foil, E C is the charging energy [J], R Al is the resistance [Ω] of the Al foil, R C is the circuit resistance [Ω].

[0030] The voltage for charging the capacitor (referred to as the charging voltage) V c [kV] is set according to the Al foil, circuit resistance, etc. The charging voltage V c is obtained by the following Equation 2.

[0031] [Equation 2] V C = {ED × 2m Al / C × (R Al + R C ) / R Al}1 / 2 Here, in equation 2 above, C is the capacitance [F].

[0032] The energy density ED [J / mg] is preferably 0.140 or more and 0.350 or less, more preferably more than 0.200 and less than 0.350, and even more preferably 0.250 or more and 0.305 or less. If the energy density ED is too low, the positive electrode active material layer 12 will be difficult to peel off from the positive electrode current collector 11. If the energy density ED is too high, the positive electrode current collector 11 will pulverize.

[0033] 2. Action and Effects In the laminate dismantling method according to this embodiment, water as a liquid is brought into contact with the positive electrode 1, which is part of the laminate, and an electrical pulse is applied in a gaseous state between the pair of electrodes in contact with the positive electrode 1. The presence of the liquid increases the physical force due to the pulse power, allowing the positive electrode active material layer 12 to be peeled off from the positive electrode current collector 11. The amount of liquid used to bring the positive electrode 1 into contact with the positive electrode is less than the amount of liquid used when applying an electrical pulse in water. According to the laminate dismantling method according to this embodiment, the generation of waste liquid can be suppressed and the peelability of the laminate can be improved.

[0034] By applying an electrical pulse in a gas, the positive electrode active material layer 12 is separated from the positive electrode current collector 11 in the gas, and the positive electrode active material can also be recovered in the gas. Compared to applying an electrical pulse in water, the recovery of the positive electrode active material is easier.

[0035] In the positive electrode 1, which is a laminate, liquid water is brought into contact with the liquid contact area 15, and a pair of electrodes are brought into contact with the electrode contact area 16, which is different from the liquid contact area 15. Depending on the working environment, the liquid may be brought into contact with the liquid contact area 15 first, and then the pair of electrodes may be brought into contact with the electrode contact area 16, or the pair of electrodes may be brought into contact with the electrode contact area 16 first, and then the liquid may be brought into contact with the liquid contact area 15. This allows for a wider range of selectivity in the work process and improves work efficiency. By dividing the positive electrode 1 into a liquid contact area 15 and an electrode contact area 16, the amount of liquid used to bring the positive electrode 1 into contact can be reduced, and the generation of waste liquid can be further suppressed.

[0036] It is suitable for use as the positive electrode in lithium-ion secondary batteries. Useful resources such as nickel and cobalt can be recovered from the positive electrode and reused.

[0037] The liquid water is brought into contact with either the front or back surface of the positive electrode 1. For example, by bringing the liquid into contact only with the front surface of the positive electrode 1, the positive electrode active material layer 12 on the front surface of the positive electrode 1 is peeled off, as is the positive electrode active material layer 12 on the back surface of the positive electrode 1. Compared to the case where the liquid is brought into contact with both the front and back surfaces of the positive electrode 1, the number of steps in the liquid contact process can be reduced, the amount of liquid used to contact the positive electrode 1 can be reduced, and the generation of waste liquid can be further suppressed.

[0038] 3. Examples The following describes the experiments conducted to confirm the effects of the present invention.

[0039] First, positive electrode 1 was removed from a lithium-ion secondary battery. Positive electrode 1 has a configuration in which positive electrode active material layers 12 are provided on both sides of a positive electrode current collector 11. The dimensions of positive electrode 1 are 210 mm in length, 80 mm in width, and 80 μm in thickness. The thickness of the positive electrode current collector 11 is 20 μm. The positive electrode current collector 11 is made of aluminum foil. The thickness of the positive electrode active material layer 12 is 30 μm. The positive electrode active material is lithium nickel cobalt aluminum composite oxide. As a laminate, positive electrode 1 that was removed from the lithium-ion secondary battery less than one month ago (hereinafter referred to as the fresh sample) and positive electrode 1 that was removed from the lithium-ion secondary battery four months ago (hereinafter referred to as the old sample) were prepared (preparation step S10). Generally, older samples are less prone to peeling of the positive electrode active material layer 12 than fresh samples because the adhesion force at the interface between the positive electrode current collector 11 (Al foil) and the positive electrode active material layer 12 increases.

[0040] Next, pure water was brought into contact with the surface of the positive electrode 1 (liquid contact step S11). Specifically, a liquid contact area 15 was set up such that the area extending 5 mm from both ends in the longitudinal direction of the positive electrode 1 became the electrode contact area 16. 0.2 mL of pure water was dropped into this liquid contact area 15 and spread and coated with a brush.

[0041] Next, a pair of electrodes were brought into contact with the positive electrode 1 (electrode contact step S12). The electrode contact area 16, which is a region of 5 mm from both ends in the longitudinal direction of the positive electrode 1, was sandwiched and brought into contact with the positive electrodes 20a, 20b and the negative electrodes 21a, 21b.

[0042] Next, an electrical pulse was applied between the pair of electrodes in a gas (electrical pulse application step S13). For fresh samples, the energy density ED [J / mg] was varied to 0.305 and 0.250, and these were designated as Examples 1 and 2, respectively. For older samples, the energy density ED [J / mg] was varied to 0.305 and 0.250, and these were designated as Examples 3 and 4, respectively.

[0043] For fresh samples, the electrode contact step S12 was performed without the liquid contact step S11, and the energy density ED [J / mg] in the electrical pulse application step S13 was changed to 0.305 and 0.250, respectively, to obtain Comparative Examples 1 and 2. For older samples, the electrode contact step S12 was performed without the liquid contact step S11, and the energy density ED [J / mg] in the electrical pulse application step S13 was changed to 0.305 and 0.250, respectively, to obtain Comparative Examples 3 and 4.

[0044] After applying electrical pulses, the Al foils of Examples 1-4 were partially pulverized and turned into powder, but generally maintained their foil form. While some of the positive electrode active material layer 12 remained on the Al foil without being completely detached, most of the positive electrode active material layer 12 was removed. Due to the physical force of the pulsed power, granular or powdery positive electrode active material was either scattered from the Al foil into the surrounding area or remained on the Al foil. The positive electrode active material remaining on the Al foil was brushed off. The granular or powdery positive electrode active material was collected and recovered. Figure 6A is a photograph showing the surface of Example 1 after applying electrical pulses. Figure 6B is a photograph showing the back surface of Example 1 after applying electrical pulses. In Figures 6A and 6B, the black areas at the edges of the Al foil represent positive electrode active material that was not detached from the Al foil. It can be confirmed that the positive electrode active material was almost completely detached from the Al foil on both the surface that came into contact with the liquid and the back surface that did not come into contact with the liquid.

[0045] For Examples 1-4 and Comparative Examples 1-4, the peeling rate [%] of the positive electrode active material was determined. The peeling rate of the positive electrode active material was calculated based on the surface area (A) of the Al foil recovered after the electrical pulse application step S13. Alr ) From the surface area (A) of the positive electrode active material layer remaining on the Al foil recovered after the electrical pulse application step S13 PEAM The value obtained by subtracting ) is the surface area (A) of the Al foil recovered after the electrical pulse application step S13. Alr The peel rate was calculated by dividing by ( ). In Examples 1 to 4, the peel rate of the positive electrode active material was determined on the surface that was in contact with the liquid and on the back surface that was not in contact with the liquid. In Comparative Examples 1 to 4, the peel rate of the positive electrode active material was determined on the surface. The results are shown in Table 1.

[0046] [Table 1]

[0047] By comparing Examples 1-4 and Comparative Examples 1-4 in Table 1, it was confirmed that, at the same energy density (ED) and sample freshness, the surface peeling rate increased with water coating. Furthermore, this trend was stronger when the energy density (ED) was 0.250 than when it was 0.305, and stronger when the sample was older than when it was fresh. Specifically, when the energy density (ED) was 0.305 and the sample was old, the surface peeling rate increased from 65.7% (Comparative Example 3) to 92.5% (Example 3) with water coating. When the energy density (ED) was 0.250 and the sample was fresh, the peeling rate increased from 43.2% (Comparative Example 2) to 88.9% (Example 2) with water coating. Moreover, when the energy density (ED) was 0.250 and the sample was old, the peeling rate increased significantly from 4.9% (Comparative Example 4) to 94.8% (Example 4) with water coating. These results confirm that even when the energy density ED is low and the physical force due to pulsed power is relatively weak, or when the sample is old and the positive electrode active material layer is difficult to peel off, a high peeling rate can be obtained by going through the liquid contact step S11. In addition, in Examples 1 to 4, it was confirmed that a high peeling rate could also be obtained on the back surface where no liquid contact was made.

[0048] The pulverization rate [%] of the Al foil was determined for Examples 1-4 and Comparative Examples 1-4. The pulverization rate of the Al foil was determined by the surface area (A) of the Al foil before the electrical pulse application step S13. Al ) From the surface area (A) of the Al foil recovered after the electrical pulse application step S13 Alr The value obtained by subtracting ) is the surface area of ​​the Al foil before the electrical pulse application process S13 (A Al The result was obtained by dividing by ). The results are shown in Table 2.

[0049] [Table 2]

[0050] Table 2 shows that in Examples 1-4, a portion of the Al foil was pulverized, but the pulverization rate of the Al foil was low, and it generally maintained its foil form. Comparing Examples 1, 3 and Comparative Examples 1, 3, with an energy density ED of 0.305, with Examples 2, 4 and Comparative Examples 2, 4, with an energy density ED of 0.250, in all cases, Examples 1, 3 and Comparative Examples 1, 3, with an energy density ED of 0.305, had a higher pulverization rate, indicating a tendency for the pulverization rate of Al foil to increase as the energy density ED increases. However, comparing Examples 1-4, which were coated with water, with Comparative Examples 1-4, which were not coated with water, no particular trend in the pulverization rate of Al foil was observed, and no change in the pulverization rate of Al foil due to liquid contact was observed. A low pulverization rate of Al foil is desirable for the separation of Al foil from the granular or powdery form of the positive electrode active material, and it was confirmed that there is no increase in the pulverization rate of Al foil due to liquid contact.

[0051] The present invention is not limited to the embodiments described above, and can be modified as appropriate within the scope of the spirit of the invention. [Explanation of Symbols]

[0052] 1. Positive electrode (laminated structure) 11. Positive electrode current collector (conductor) 12 Positive electrode active material layer (layer) 15 Liquid contact area 16 Electrode contact area S10 Preparation process S11 Liquid contact process S12 Electrode contact process S13 Electrical pulse application process

Claims

1. Water is brought into contact with a laminate having a conductor and a layer laminated on the conductor. An electrical pulse is applied in a gas between a pair of electrodes in contact with the laminate, A method for dismantling a laminate, comprising peeling the layer from the conductor.

2. The water is brought into contact with the liquid contact area of ​​the laminate, The method for dismantling a laminate according to claim 1, wherein the pair of electrodes are brought into contact with an electrode contact area of ​​the laminate that is different from the liquid contact area.

3. The aforementioned laminate is the positive electrode of a lithium-ion secondary battery. The aforementioned conductor is a positive electrode current collector, The method for dismantling a laminate according to claim 1, wherein the layer is a positive electrode active material layer.

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