Manufacturing method of current collector foil
The method of impregnating adhesive into pinholes in current collector foils using a suction process addresses the issue of pinholes, enhancing the integrity and reliability of liquid-based batteries by reducing through-holes and electrolyte leakage.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- TOYOTA JIDOSHA KK
- Filing Date
- 2023-10-10
- Publication Date
- 2026-05-15
AI Technical Summary
Current collector foils for liquid-based batteries are prone to pinholes during manufacturing, leading to through-holes and liquid junctions when used in batteries, which can cause electrolyte leakage and electrode degradation.
A manufacturing method involving a suction step to impregnate adhesive into pinholes of one electrode foil before bonding with another electrode foil, followed by drying and heat welding, using a suction member with specific hole diameters, spacings, and pressures to seal the pinholes.
Reduces the number of pinholes, preventing through-holes and electrolyte intrusion, thereby suppressing liquid junctions and electrode degradation in liquid-based batteries.
Smart Images
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Abstract
Description
Technical Field
[0001] The present disclosure relates to a method for manufacturing a current collector foil.
Background Art
[0002] Conventionally, a current collector foil for a liquid battery in which a positive electrode foil and a negative electrode foil are bonded together has been used.
[0003] For example, Patent Document 1 discloses a bipolar current collector having a positive electrode current collector having an aluminum layer, a negative electrode current collector having a copper layer, and an intervening layer interposed between the aluminum layer and the copper layer, wherein the thickness of the copper layer is 3 to 10 μm, and the intervening layer has a porous anodic oxide part and a nickel part present in the pores of the anodic oxide part.
[0004] Further, Patent Document 2 discloses a laminated all-solid-state secondary battery in which a positive electrode, a solid electrolyte layer, and a negative electrode are laminated to form an electrical parallel connection in a parallel electrode body, and a plurality of parallel electrode bodies are electrically connected in series via a bipolar electrode. The bipolar electrode is disposed facing the positive electrode and the negative electrode, and the bipolar electrode current collector foil, the positive electrode current collector foil of the positive electrode disposed facing the bipolar electrode, and the negative electrode current collector foil of the negative electrode are separated.
Prior Art Documents
Patent Documents
[0005]
Patent Document 1
Patent Document 2
Summary of the Invention
Problems to be Solved by the Invention
[0006] Conventionally, current collector foils for liquid-based batteries have been made by bonding a positive electrode foil and a negative electrode foil together with an adhesive. However, pinholes can occur in the metal foils used for the positive and negative electrode foils during the manufacturing process. When a current collector foil with pinholes in at least one of the positive or negative electrode foils is used in a liquid-based battery, a through-hole is created that penetrates the positive electrode foil, the adhesive layer, and the negative electrode foil, and liquid junctions can occur in the liquid-based battery through this through-hole.
[0007] This disclosure is made in view of the above circumstances and aims to provide a method for manufacturing current collector foil that can reduce the number of pinholes in the current collector foil. [Means for solving the problem]
[0008] The means for solving the above problems include the following embodiments. <1> A method for manufacturing a current collector foil for a liquid-based battery, comprising bonding a first electrode foil having pinholes and a second electrode foil together, The first electrode foil and the second electrode foil are such that one is a positive electrode foil and the other is a negative electrode foil. A coating step of applying adhesive to the first electrode foil, A suction step is performed on the side of the first electrode foil opposite to the side to which the adhesive is applied, thereby impregnating the pinholes with the adhesive. A drying step for drying the adhesive, A heat welding step of bonding the second electrode foil to the surface of the first electrode foil to which the adhesive has been applied and heat welding it, A method for manufacturing current collector foil having the following characteristics. <2> The suction step involves bringing a suction member having suction holes on its surface into contact with the side of the first electrode foil opposite to the side to which the adhesive is applied, and performing suction. <1> A method for manufacturing current collector foil as described above. <3> The diameter of the aforementioned suction hole is 0.5 mm or more and 15 mm or less. <2> A method for manufacturing current collector foil as described above. <4> The spacing between the suction holes is 1.0 mm or more and 20 mm or less. <2> A method for manufacturing current collector foil as described above. <5> The suction pressure from the aforementioned suction hole is 5 kPa or more and 40 kPa or less. <2> A method for manufacturing current collector foil as described above. [Effects of the Invention]
[0009] According to this disclosure, a method for manufacturing current collector foil is provided that can reduce the number of pinholes in the current collector foil. [Brief explanation of the drawing]
[0010] [Figure 1] This is a schematic diagram showing a current collector foil manufacturing apparatus that implements a current collector foil manufacturing method according to the embodiment of this disclosure. [Figure 2] This is a schematic cross-sectional view showing how adhesive is impregnated into a pinhole during the suction step in a method for manufacturing a negative electrode for a battery according to an embodiment of the present disclosure. [Figure 3] This is a schematic cross-sectional view showing how adhesive is impregnated into a pinhole during the suction step in a method for manufacturing a negative electrode for a battery according to an embodiment of the present disclosure. [Figure 4] This is a schematic cross-sectional view showing how adhesive is impregnated into a pinhole during the suction step in a method for manufacturing a negative electrode for a battery according to an embodiment of the present disclosure. [Modes for carrying out the invention]
[0011] An example embodiment of this disclosure will be described. These descriptions and examples are illustrative and do not limit the scope of the invention. In this specification, numerical ranges represented by "~" mean a range that includes these values as the lower and upper limits. In the numerical ranges described stepwise in this specification, the upper limit of one stepwise numerical range may be replaced with the upper limit of another stepwise numerical range, or with the values shown in the examples. Similarly, the lower limit of one stepwise numerical range may be replaced with the lower limit of another stepwise numerical range, or with the values shown in the examples. In addition, regarding the content, unless otherwise specified, "%" means "% by mass".
[0012] Each component may contain a plurality of corresponding substances. When referring to the amount of each component in the composition, if there are a plurality of substances corresponding to each component in the composition, unless otherwise specified, it means the total amount of the plurality of substances present in the composition. The term "process" includes not only independent processes but also those that cannot be clearly distinguished from other processes as long as the intended function of the process is achieved.
[0013] <Method for manufacturing a current collector foil> The method for manufacturing a current collector foil according to an embodiment of the present disclosure is a manufacturing method for obtaining a current collector foil for a liquid-based battery (that is, a battery having an electrolyte solution as an electrolyte) by laminating a first electrode foil having pinholes and a second electrode foil. Note that one of the first electrode foil and the second electrode foil is a positive electrode foil and the other is a negative electrode foil. And the method for manufacturing a current collector foil has the following steps (1) to (4). (1) Coating step of applying an adhesive to the first electrode foil (2) Suction step of performing suction from the side opposite to the surface of the first electrode foil on which the adhesive is applied and impregnating the pinholes with the adhesive (3) Drying step of drying the adhesive (4) Heat welding step of laminating and heat welding the second electrode foil to the surface of the first electrode foil on which the adhesive is applied
[0014] The method for manufacturing a current collector foil according to an embodiment of the present disclosure can reduce the number of pinholes in the current collector foil by having a suction step between the coating step and the drying step as described above. As a result, when this current collector foil is used in a liquid-based battery, the generation of through-holes occurring in the current collector foil can be suppressed, and the generation of liquid leakage in the liquid-based battery can be suppressed.
[0015] Conventionally, current collector foils have been used in which a positive electrode foil and a negative electrode foil are bonded together with an adhesive. However, pinholes (small holes penetrating the metal foil) can occur during the manufacturing process of the metal foils used for the positive and negative electrode foils.
[0016] For example, if a positive electrode foil with pinholes is used, and a current collector foil obtained by bonding this positive electrode foil and a negative electrode foil with an adhesive is used in a liquid-based battery, a through-hole may be formed at the location of the pinhole in the positive electrode foil, penetrating the positive electrode foil, the adhesive layer, and the negative electrode foil. Specifically, at the location of the pinhole in the positive electrode foil, a hole may also be formed in the adhesive layer formed on top of the pinhole, meaning that the pinhole may not be sealed by the adhesive. When this current collector foil, obtained by bonding the negative electrode foil to the positive electrode foil and adhesive layer, is used in a liquid-based battery, the electrolyte can enter the hole penetrating the positive electrode foil and adhesive layer, and this electrolyte will come into contact with the negative electrode foil. If the battery is repeatedly charged and discharged in this state, a reaction with the electrolyte (for example, if copper foil is used as the negative electrode foil, Cu → Cu) will occur. 2+ +2e - The reaction may also create holes in the negative electrode foil. As a result, through holes are formed that completely penetrate the positive electrode foil, the adhesive layer, and the negative electrode foil. Furthermore, when a current collector foil obtained by bonding a negative electrode foil with pinholes to a positive electrode foil via an adhesive is used in a liquid-based battery, a through-hole may occur at the location of the pinhole in the positive electrode foil, penetrating the positive electrode foil, the adhesive layer, and the negative electrode foil. Specifically, at the location of the pinhole in the negative electrode foil, a hole may also be formed in the adhesive layer formed on top of the pinhole, meaning the pinhole may not be sealed by the adhesive. When a current collector foil obtained by bonding a positive electrode foil to this negative electrode foil and adhesive layer is used in a liquid-based battery, the electrolyte can enter the hole penetrating the negative electrode foil and adhesive layer, and this electrolyte will come into contact with the positive electrode foil. If the battery is repeatedly charged and discharged in this state, cracks may occur in the positive electrode foil, resulting in the formation of a through-hole that completely penetrates the negative electrode foil, the adhesive layer, and the positive electrode foil.
[0017] Furthermore, in current collector foils in which through-holes are formed that penetrate the positive electrode foil, adhesive layer, and negative electrode foil, liquid junctions occur because one side of the current collector foil is connected to the other side through the through-holes.
[0018] Therefore, in the method for manufacturing a current collector foil according to the embodiment of this disclosure, a suction step is provided in which, after applying an adhesive to the first electrode foil but before drying the adhesive, suction is performed from the side of the first electrode foil opposite to the side to which the adhesive is applied. This suction step allows the undried (i.e., liquid) adhesive to impregnate the pinholes in the first electrode foil, filling the pinholes. As a result, even when the current collector foil is used in a liquid-based battery, the intrusion of electrolyte into the pinholes of the first electrode foil is suppressed, and the formation of through holes that completely penetrate the positive electrode foil, adhesive layer, and negative electrode foil is suppressed. As a result, the occurrence of liquid junctions in liquid-based batteries can be suppressed.
[0019] Here, one embodiment of the method for manufacturing a current collector foil according to the present disclosure will be described in detail with reference to the drawings.
[0020] Figure 1 is a schematic diagram showing a current collector foil manufacturing apparatus that implements the current collector foil manufacturing method according to the embodiment of this disclosure. The current collector foil manufacturing apparatus 100 shown in Figure 1 includes a positive electrode foil 12 (e.g., Al foil) as an example of a first electrode foil formed into a roll shape, and a negative electrode foil 14 (e.g., Cu foil) as an example of a second electrode foil formed into a roll shape. The positive electrode foil 12 is a metal foil having pinholes.
[0021] (1) Coating process First, the positive electrode foil 12 is transported to a roll pair consisting of a coating roll 22A (e.g., a gravure roll) and a counter roll 22B. Part of the coating roll 22A is immersed in adhesive 40, and the adhesive 40 adhering to the surface of the coating roll 22A is applied (e.g., gravure coating) from the coating roll 22A to one side of the positive electrode foil 12.
[0022] (2) Suction process Next, the positive electrode foil 12, on which adhesive 40 has been applied to one side, is transported to a position where it contacts a suction roll 24, which is an example of a component having a suction mechanism (hereinafter also simply referred to as a "suction component"). The suction roll 24 is positioned in contact with the side of the positive electrode foil 12 on which adhesive 40 has not been applied. Then, suction is applied from the side of the positive electrode foil 12 on which adhesive 40 has not been applied by the suction roll 24. This allows the adhesive 40 to be impregnated into the pinholes in the positive electrode foil 12.
[0023] More specifically, as shown in Figure 2, in the positive electrode foil 12, where a pinhole 120 is formed, a hole may also be formed in the adhesive 40 applied on top of the pinhole 120. As shown in Figure 3, when suction is applied to the positive electrode foil 12 from the side of the positive electrode foil 12 where the adhesive 40 is not applied, in the direction of arrow A by the suction roll 24, a negative pressure is created inside the pinhole 120 in the positive electrode foil 12, causing the adhesive 40 to flow in the direction of arrow B. As a result, as shown in Figure 4, the adhesive 40 impregnates the pinhole 120, and the pinhole 120 is sealed.
[0024] Here, we will explain suction components such as suction rolls. A suction roll is a roll that can perform suction through suction holes provided on its surface. Figure 1 shows a suction roll 24 as a suction member used in the suction process, but this disclosure is not limited thereto. The suction member used in the embodiments of this disclosure is not particularly limited as long as it is a member that can perform suction from the side of the first electrode foil opposite to the side to which the adhesive is applied. For example, a belt having suction holes on its surface (hereinafter referred to as a "suction belt") may be used.
[0025] The diameter of the suction holes provided on the surface of the suction member (suction roll 24 in Figure 1) (the arithmetic mean of the diameters of 20 arbitrarily selected suction holes) is preferably 0.5 mm to 15 mm, and more preferably 1.0 mm to 10 mm, from the viewpoint of making it easier to reduce the number of pinholes in the current collector foil. The spacing between suction holes on the surface of the suction member (suction roll 24 in Figure 1) (the distance between the center points of adjacent suction holes, or the arithmetic mean of the distances between the center points of 20 arbitrarily selected sets of suction holes) is preferably 1.0 mm to 20 mm, and more preferably 2.0 mm to 10 mm, from the viewpoint of making it easier to reduce the number of pinholes in the current collector foil. The suction pressure from the suction holes in the suction member (suction roll 24 in Figure 1) is preferably 5 kPa or more and 40 kPa or less, and more preferably 10 kPa or more and 30 kPa or less, from the viewpoint of making it easier to reduce the number of pinholes in the current collector foil.
[0026] The suction member is preferably roll-shaped (for example, the suction roll 24 shown in Figure 1). The gripping angle of this roll-shaped suction member (i.e., the angle formed by the direction of travel of the first electrode foil on the side away from the suction roll and the direction of travel of the first electrode foil on the side entering the suction roll) is preferably 40° to 100°, and more preferably 50° to 90°, from the viewpoint of making it easier to reduce the number of pinholes in the current collector foil.
[0027] Furthermore, the surface material of the suction member having a roll shape (for example, the suction roll 24 shown in Figure 1) is preferably metal, and particularly preferably stainless steel (SUS). Furthermore, resin and rubber are preferred as the surface material of the suction belt.
[0028] (3) Drying process Next, as shown in Figure 1, the positive electrode foil 12 that has undergone the suction process by the suction roll 24 is transported to the drying oven 30, where the adhesive 40 on the positive electrode foil 12 is heated and dried in the drying oven 30.
[0029] The heating temperature in the drying process (the temperature inside the drying oven 30 in Figure 1) can be adjusted depending on the adhesive used. For example, it is preferably 80°C to 200°C, and more preferably 100°C to 180°C.
[0030] (4) Heat welding process Next, the positive electrode foil 12 that has passed through the drying oven 30 is transported via the transport roll 26 to a contact position with the heat roll pair 28A and 28B. At the nip portion of the heat roll pair 28A and 28B, the negative electrode foil 14, which has been transported from a different direction, is bonded to the surface of the positive electrode foil 12 to which the adhesive 40 has been applied, and is heated and pressurized by the heat roll pair 28A and 28B, thereby heat-welding the positive electrode foil 12 and the negative electrode foil 14 via the adhesive 40. Through these processes, a current collector foil 10 is manufactured by bonding the positive electrode foil 12 and the negative electrode foil 14 together.
[0031] The heating temperature in the heat welding process (the temperature of the heat roll pair 28A and 28B in Figure 1) can be adjusted depending on the adhesive used. For example, it is preferably 50°C to 150°C, and more preferably 70°C to 120°C. Furthermore, the pressure applied during the heat welding process (nip pressure by the heat rolls 28A and 28B in Figure 1) is preferably 0.20 MPa or more and 0.70 MPa or less, and more preferably 0.30 MPa or more and 0.60 MPa or less.
[0032] In Figure 1, a manufacturing method is described in which an adhesive 40 is applied to a positive electrode foil 12 having pinholes (application step), and then the negative electrode foil 14 is bonded and heat-welded (heat-welding step). However, this disclosure is not limited to this. In other words, the manufacturing method may also involve applying an adhesive to a negative electrode foil having pinholes (application step), and then the positive electrode foil is bonded and heat-welded (heat-welding step).
[0033] In the method for manufacturing a current collector foil according to the embodiment of this disclosure, one of the first electrode foil and the second electrode foil is a positive electrode foil, and the other is a negative electrode foil.
[0034] The positive electrode foil to be used is preferably a conductive material made of a metal with good conductivity (e.g., aluminum). The thickness of the positive electrode foil is preferably 10 μm to 100 μm, and more preferably 20 μm to 60 μm.
[0035] On the other hand, a conductive material made of a metal with good conductivity (for example, copper) is preferred as the negative electrode foil. The thickness of the negative electrode foil is preferably, for example, 1 μm to 20 μm, and more preferably 3 μm to 12 μm.
[0036] The adhesive used in the method for manufacturing current collector foil according to the embodiments of this disclosure is not particularly limited as long as it is a liquid adhesive before the drying process. For example, an adhesive to which a curing agent (e.g., an isocyanate-based curing agent) is added to a main component (e.g., an olefin-based resin) is preferably used. A conductive additive (e.g., particles with a Ni plating on the surface) may also be added to the adhesive. The thickness of the adhesive layer formed by applying and drying the adhesive is preferably 0.5 μm to 15 μm, and more preferably 1.0 μm to 10 μm.
[0037] <Battery> Next, we will describe the components that constitute a liquid-based battery using a current collector foil obtained by the current collector foil manufacturing method according to the embodiment of this disclosure.
[0038] (Cathode active material layer) The positive electrode composite layer contains a positive electrode active material and may further contain, for example, a binder. Examples of positive electrode active materials include lithium nickel cobalt manganese composite oxide (hereinafter sometimes simply referred to as "LNCM"). The simplest LNCM is given by the following general formula: LiNi x Co y Mn zIt is represented by O2 (where x, y, and z satisfy 0 < x < 1, 0 < y < 1, 0 < z < 1, and x + y + z = 1). LNCM may contain other additive elements in addition to Li, Ni, Co, and Mn, such as transition metal elements other than Ni, Co, and Mn, and typical metal elements other than Li. LNCM has a layered crystal structure. LNCM may exceed 50% by mass of the entire cathode active material and, for example, may account for 80 - 100% by mass. The cathode active material may be composed of only LNCM. Examples of other cathode active materials include lithium nickel composite oxides, lithium cobalt composite oxides, lithium nickel manganese composite oxides, and the like.
[0039] Examples of the binder contained in the cathode composite layer include vinyl halide resins such as polyvinylidene fluoride (PVdF). The cathode composite layer may further contain other components, such as a conductive material. Examples of the conductive material include graphitized carbon, easily graphitizable carbon such as carbon black, and graphite.
[0040] (Negative electrode active layer) The aforementioned negative electrode active material layer is used for the negative electrode active layer. Since the details have already been described, they are omitted here.
[0041] (Separator) The separator is an electrically insulating porous membrane. The separator electrically isolates the positive electrode and the negative electrode. The separator may have a thickness of, for example, 5 - 30 μm. The separator may be composed of, for example, a porous polyethylene (PE) membrane, a porous polypropylene (PP) membrane, or the like. The separator may have a multilayer structure. For example, the separator may be composed of a porous PP membrane, a porous PE membrane, and a porous PP membrane laminated in this order. The separator may have a heat-resistant layer on its surface. The heat-resistant layer contains a heat-resistant material. Examples of the heat-resistant material include metal oxide particles such as alumina and high melting point resins such as polyimide.
[0042] (Electrolyte) A battery according to the embodiments of this disclosure further comprises an electrolyte. A non-aqueous electrolyte is particularly preferred.
[0043] ·solvent Non-aqueous electrolytes contain a solvent (non-aqueous solvent) and an electrolyte. Examples of solvents (non-aqueous solvents) include N,N-diethyl-N-methyl-N-(2-methoxyethyl)ammonium bis(fluorosulfonyl)imide (DEME), 1-ethyl-3-methylimidazolium bis(fluorosulfonyl)imide (EMI), and 1-ethyl-2,3-dimethylimidazolium bis(fluorosulfonyl)imide (DEMI-FSI).
[0044] ·Electrolyte Examples of electrolytes in electrolyte solutions include lithium salts. Examples of lithium salts include lithium bis(fluorosulfonyl)imide (LiFSI), LiPF6 (lithium hexafluoride phosphate), lithium tetrafluoroborate (LiBF4), and Li[N(CF3SO2)2]. The amount of electrolyte may be, for example, 1.0 to 2.0 ml / L, and preferably 1.0 to 1.5 ml / L.
[0045] The electrolyte may contain various additives in addition to the solvent and electrolyte, such as thickeners, film-forming agents, and gas-generating agents. The electrolyte is typically a non-aqueous electrolyte that is liquid at room temperature (e.g., 25±10°C). The electrolyte is typically liquid under the battery's operating environment (e.g., a temperature environment of -20 to +60°C).
[0046] (Application) Applications of the battery according to the embodiments of this disclosure include, for example, power sources for hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (PHEVs), and battery electric vehicles (BEVs). [Examples]
[0047] The present disclosure will be described below based on examples, but the present disclosure is not limited in any way to these examples.
[0048] <Examples> • Preparation of adhesives Adhesive 1 was obtained by mixing an olefin resin as the main component, an isocyanate-based curing agent, and Ni-plated particles as a conductive additive.
[0049] • Fabrication of current collector foil In the current collector foil manufacturing apparatus 100 shown in Figure 1, adhesive 1 was used as adhesive 40, aluminum foil (Al foil) was used as positive electrode foil 12, and copper foil (Cu foil) was used as negative electrode foil 14. The line speed (conveying speed) was set to 15 m / min.
[0050] Adhesive 1 was applied to one side of the Al foil by gravure coating (coating process). A gravure roll (elongated, 75 lines) was used for the coating roll 22A.
[0051] Next, the suction roll 24 was used to suction the Al foil from the side opposite to the side to which the adhesive 1 was applied, under the following conditions (suction step). (Conditions for suction rolls) Suction hole diameter: φ2mm Suction hole spacing (distance between the center points of the suction holes): 4 mm Suction pressure: 20kPa Suction roll gripping angle: 50°~90° Suction roll material: SUS
[0052] Next, the adhesive 1 was dried by passing it through a drying oven 30 set to a temperature of 150°C (drying process). Subsequently, the Al foil, which had been transported to the heat roll pair 28A and 28B, was heat-welded by bonding the Cu foil to the side coated with adhesive 1 (heat welding process) to obtain the current collector foil of the embodiment. The conditions for the heat roll pair 28A and 28B were as follows. Temperature of the heated roll pair: 90℃ Nip pressure of the hot roll pair: 0.45 MPa
[0053] <Comparative Example> A comparative example of current collector foil was obtained in the same manner as in Example 1, except that the suction roll 24 in the current collector foil manufacturing apparatus 100 shown in Figure 1 was replaced with a SUS roll that does not have a suction mechanism, i.e., the suction process was omitted.
[0054] [Evaluation Test] • Pinhole inspection For each current collector foil obtained in the examples and comparative examples, the presence or absence of pinholes with a diameter of 0.5 mm or less was detected using an inspection machine. The results are shown in Table 1 below.
[0055] [Table 1]
[0056] In the current collector foil of the example in which suction is applied using a suction roll 24 after applying adhesive 1, it can be seen that the number of pinholes is reduced compared to the current collector foil of the comparative example in which suction is not applied. [Explanation of Symbols]
[0057] 10 Current collector foil, 12 Positive electrode foil, 14 Negative electrode foil, 22A Coating roll, 22B Opposing roll, 24 Suction roll, 26 Conveyor roll, 28A, 28B Heating roll pair, 30 Drying oven, 40 Adhesive, 100 Current collector foil manufacturing equipment, 120 Pinhole
Claims
1. A method for manufacturing a current collector foil for a liquid-based battery, comprising bonding a first electrode foil having pinholes and a second electrode foil together, The first electrode foil and the second electrode foil are such that one is a positive electrode foil and the other is a negative electrode foil. A coating step of applying adhesive to the first electrode foil, A suction step is performed on the side of the first electrode foil opposite to the side to which the adhesive is applied, thereby impregnating the pinholes with the adhesive. A drying step for drying the adhesive, A heat welding step of bonding the second electrode foil to the surface of the first electrode foil to which the adhesive has been applied and heat welding it, A method for manufacturing current collector foil having the following characteristics.
2. The method for manufacturing a current collector foil according to claim 1, wherein the suction step is a step of bringing a suction member having suction holes on its surface into contact with the side of the first electrode foil opposite to the side to which the adhesive is applied, and performing suction.
3. The method for manufacturing a current collector foil according to claim 2, wherein the diameter of the suction hole is 0.5 mm or more and 15 mm or less.
4. The method for manufacturing a current collector foil according to claim 2, wherein the spacing between the suction holes is 1.0 mm or more and 20 mm or less.
5. The method for manufacturing a current collector foil according to claim 2, wherein the suction pressure from the suction hole is 5 kPa or more and 40 kPa or less.