Manufacturing method for electrode stack modules
The method creates a concentration gradient in the electrolyte to prevent ethylene carbonate-derived SEI film formation on the negative electrode, promoting vinylene carbonate-derived SEI film formation, thus reducing gas generation and enhancing battery safety and performance.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- TOYOTA JIDOSHA KK
- Filing Date
- 2024-12-13
- Publication Date
- 2026-06-25
AI Technical Summary
Existing methods to suppress gas generation in lithium-ion secondary batteries during charging and discharging are inadequate, as the formation of an SEI film derived from ethylene carbonate on the negative electrode active material layer leads to gas generation and battery swelling, which can cause short circuits and fire risks.
A manufacturing method for electrode stack modules involves injecting a non-aqueous electrolyte into a precursor containing a positive electrode active material layer with ethylene carbonate, creating a concentration gradient to suppress ethylene carbonate-derived SEI film formation on the negative electrode, while promoting vinylene carbonate-derived SEI film formation by maintaining higher vinylene carbonate concentration on the negative electrode side.
This method effectively suppresses ethylene carbonate-derived SEI film formation, reducing gas generation and battery swelling, thereby enhancing safety and performance by ensuring the formation of a preferred SEI film on the negative electrode.
Smart Images
Figure 2026104269000001_ABST
Abstract
Description
[Technical Field]
[0001] This disclosure relates to a method for manufacturing an electrode stack module. [Background technology]
[0002] An electrode stack module consists of an electrode stack housed in an outer container with an electrolyte solution poured into it. The electrode stack comprises a positive electrode active material layer, a separator layer, and a negative electrode active material layer in that order.
[0003] In electrode stack modules, such as lithium-ion secondary batteries, a Solid Electrolyte Interphase (SEI) coating is formed at the electrolyte interface of the active material layer during charging and discharging.
[0004] The SEI coating is thought to contribute to improved performance by suppressing further decomposition of the electrolyte while also facilitating the insertion and removal of lithium ions from the active material layer.
[0005] However, during the initial charging process, a problem arises in that gas is generated inside the battery due to the decomposition of carbonate-based organic solvents during the reaction that forms the SEI film. These gases include H2, CO, CO2, CH4, C2H6, C2H4, C3H8, and C3H6, depending on the type of non-aqueous organic solvent and negative electrode active material. This gas generation is caused by oxidation and reduction of the electrolyte and electrodes during the charge-discharge reaction, and repeated charging and discharging of lithium-ion secondary batteries also generates gas. This gas generation inside the battery can cause it to swell during charging. Such a swollen battery has a altered internal structure, leading to a short circuit between the positive and negative electrodes and a risk of fire. Therefore, various methods are being investigated to suppress the gas generated during charging and discharging.
[0006] For example, Patent Document 1 discloses an electrolyte for a lithium secondary battery characterized by comprising a lithium salt containing LiPF6 and LiBF4; a non-aqueous organic solvent containing a high-boiling point organic solvent; and vinylene carbonate. The electrolyte described in Patent Document 1 is said to provide a lithium secondary battery with excellent lifespan characteristics, as it hardly exhibits the swelling phenomenon due to gas generation. [Prior art documents] [Patent Documents]
[0007] [Patent Document 1] Japanese Patent Publication No. 2005-056841 [Overview of the project] [Problems that the invention aims to solve]
[0008] As described in Patent Document 1, by including vinylene carbonate in the electrolyte and forming an SEI film derived from vinylene carbonate, gas generation inside the battery can be suppressed. However, even when the electrolyte contains vinylene carbonate, an SEI film derived from another electrolyte component, such as ethylene carbonate, may form on the negative electrode active material layer before the SEI film derived from vinylene carbonate is formed on the negative electrode active material layer.
[0009] Therefore, the present disclosure aims to suppress the formation of an SEI film derived from ethylene carbonate on the negative electrode active material layer during the initial charging of the electrode stack module. [Means for solving the problem]
[0010] This disclosure aims to achieve the above objectives by the following means:
[0011] (Aspect 1) (a) To provide an electrode stack module precursor comprising an electrode stack and an outer container, (b) Injecting a non-aqueous electrolyte into the electrode laminate module precursor, (c) The electrode laminate module precursor into which the above non-aqueous electrolyte has been injected is charged and discharged. Includes, The above electrode laminate comprises a positive electrode active material layer, a separator layer, and a negative electrode active material layer in this order. The above outer container houses the electrode stack inside, Before the injection of the liquid in step (b), the positive electrode active material layer contains ethylene carbonate, and During the charging and discharging of step (c), the concentration of ethylene carbonate in the non-aqueous electrolyte on the negative electrode active material layer side is lower than the concentration of ethylene carbonate in the non-aqueous electrolyte on the positive electrode active material layer side. A method for manufacturing an electrode stack module. (Aspect 2) The above non-aqueous electrolyte contains vinylene carbonate, The method according to embodiment 1, wherein during the charging and discharging of step (c), the concentration of vinylene carbonate in the non-aqueous electrolyte on the negative electrode active material layer side is higher than the concentration of vinylene carbonate in the non-aqueous electrolyte on the positive electrode active material layer side. (Aspect 3) The method according to embodiment 1 or 2, comprising preparing the positive electrode active material layer and the negative electrode active material layer by either wet powder deposition or dry deposition. (Aspect 4) The method according to any one of embodiments 1 to 3, wherein in step (a), the electrode stack module precursor is provided at 35°C or below. [Effects of the Invention]
[0012] According to the method disclosed herein, it is possible to suppress the formation of an SEI film derived from ethylene carbonate on the negative electrode active material layer during the initial charging of the electrode stack module. [Brief explanation of the drawing]
[0013] [Figure 1] Figure 1 is a schematic diagram illustrating the method of this disclosure. [Figure 2] Figure 2 is a schematic diagram for explaining the prior art. [Figure 3] Figure 3 is a schematic diagram for explaining an embodiment of the present disclosure. [Figure 4] Figure 4 is a graph showing the results of an embodiment of the present disclosure.
Embodiments for Carrying Out the Invention
[0014] ≪Method for Manufacturing an Electrode Stack Module≫ The method of the present disclosure for manufacturing an electrode stack module includes (a) providing a precursor of an electrode stack module including an electrode stack and an exterior container; (b) injecting a non-aqueous electrolyte into the precursor of the electrode stack module; and (c) charging and discharging the precursor of the electrode stack module injected with the non-aqueous electrolyte. The electrode stack includes a positive electrode active material layer, a separator layer, and a negative electrode active material layer in this order. The exterior container houses the electrode stack therein. Before the injection in step (b), the positive electrode active material layer contains ethylene carbonate, and During the charging and discharging in step (c), the concentration of ethylene carbonate in the non-aqueous electrolyte on the negative electrode active material layer side is lower than the concentration of ethylene carbonate in the non-aqueous electrolyte on the positive electrode active material layer side. According to the above method, it is possible to suppress the formation of an SEI film derived from ethylene carbonate on the negative electrode active material layer during the initial charging of the electrode stack module.
[0015]
[0016] As shown in Figure 2, in the conventional method, since the electrolyte contains ethylene carbonate, during charging and discharging, the ethylene carbonate comes into contact with the negative electrode active material 142, and an ethylene carbonate-derived SEI film 144 is formed. The ethylene carbonate-derived SEI film 144 tends to generate gas 300 during charging and discharging, which may degrade battery performance, so it is undesirable to form an ethylene carbonate-derived SEI film 144 on the negative electrode active material 142.
[0017] Furthermore, if the electrolyte contains vinylene carbonate, it is preferable to preferentially form the vinylene carbonate-derived SEI film 146 on the negative electrode active material 142. However, sometimes the ethylene carbonate-derived SEI film 144 was formed before the vinylene carbonate-derived SEI film 146 was formed on the negative electrode active material 142.
[0018] In contrast, according to the present disclosure, when a non-aqueous electrolyte is injected into an electrode laminate module precursor, which includes an electrode laminate comprising a positive electrode active material layer and a negative electrode active material layer, and an outer container having the electrode laminate inside, the injection of the non-aqueous electrolyte is performed while the positive electrode active material layer contains ethylene carbonate.
[0019] By incorporating ethylene carbonate into the positive electrode active material layer before injection, the ethylene carbonate content in the non-aqueous electrolyte can be reduced. Furthermore, after injection, the ethylene carbonate gradually dissolves in the non-aqueous electrolyte and diffuses into it. This allows for the formation of an ethylene carbonate concentration gradient in the non-aqueous electrolyte after injection. Therefore, when the non-aqueous electrolyte contains vinylene carbonate, as shown in Figure 1, the formation of an ethylene carbonate-derived SEI film 144 on the negative electrode active material 142 of the negative electrode active material layer can be suppressed, and a vinylene carbonate-derived SEI film 146 is formed on the negative electrode active material 142. Note that Figure 1 is one embodiment, and this disclosure is not limited thereto.
[0020] The embodiments of this disclosure will be described in detail below. However, this disclosure is not limited to the embodiments described below, and can be implemented in various ways within the scope of the gist of this disclosure. Furthermore, in the description of the drawings, the same elements are denoted by the same reference numerals, and redundant descriptions are omitted.
[0021] <Process (a)> In the method for manufacturing an electrode stack module according to this disclosure, first, an electrode stack module precursor comprising an electrode stack and an outer container is provided.
[0022] In this disclosure, in order to suppress the melting of ethylene carbonate, step (a) may provide the electrode laminate module precursor at a temperature below the melting point of ethylene carbonate (36.4°C). The temperature in step (a) may be, but is not limited to, 36°C or below, 35°C or below, 33°C or below, 30°C or below, 25°C or below, 20°C or below, or 15°C or below.
[0023] (Electrode stack module) In this disclosure, the electrode stack module is obtained by pouring a non-aqueous electrolyte into an outer container that houses the electrode stack.
[0024] (Electrode stack module precursor) In this disclosure, the electrode stack module precursor comprises an electrode stack and an outer container. In this disclosure, the electrode stack module precursor is obtained, for example, by housing the electrode stack in an outer container.
[0025] (Electrode stack) In this disclosure, the electrode laminate comprises a positive electrode active material layer, a separator layer, and a negative electrode active material layer in this order.
[0026] In this disclosure, the positive electrode active material layer and the negative electrode active material layer are not particularly limited, but can be manufactured by known methods for manufacturing positive electrode active material layers and negative electrode active material layers. In this disclosure, the ethylene carbonate contained in the positive electrode active material layer is solid at room temperature (25°C) and is a component contained in the non-aqueous electrolyte, so it is not necessary to dry and remove the ethylene carbonate after the deposition of the positive electrode active material layer, and the positive electrode active material layer of the electrode stack module precursor may contain ethylene carbonate. Therefore, the positive electrode active material layer and / or the negative electrode active material layer may be manufactured by either wet powder deposition or dry deposition.
[0027] (Cathode active material layer) In this disclosure, the positive electrode active material layer contains at least a positive electrode active material and ethylene carbonate. The positive electrode active material layer may further contain at least one of a solid electrolyte, a conductive additive, and a binder, as needed. The content of the solid electrolyte, conductive additive, and binder optionally contained in the positive electrode active material layer is not particularly limited.
[0028] In this disclosure, ethylene carbonate is not particularly limited, but it is contained on the surface of the positive electrode active material layer on the separator layer side, on the surface of the positive electrode active material layer on the positive electrode current collector layer side, or within the positive electrode active material layer. In order to maintain for a long time the concentration difference of ethylene carbonate between the positive electrode active material layer and the negative electrode active material layer due to the concentration gradient of ethylene carbonate formed in the non-aqueous electrolyte, ethylene carbonate is preferably contained within the positive electrode active material layer, and more preferably on the surface of the positive electrode active material layer on the positive electrode current collector layer side.
[0029] The material of the positive electrode active material is not particularly limited. Examples of positive electrode active materials include lithium cobalt oxide (LiCoO2), lithium nickel oxide (LiNiO2), lithium manganese oxide (LiMn2O4), and nickel-cobalt-lithium manganese oxide (NCM:LiCO2). 1 / 3 Ni 1 / 3 Mn 1 / 3 O2), lithium nickel-cobalt aluminum oxide (LiNi 0.8 (CoAl) 0.2O2), Li 1+x Mn 2-x-y M y It may be, but is not limited to, a heteroatom-substituted Li-Mn spinel or the like having a composition represented by O4 (M is one or more metal elements selected from Al, Mg, Co, Fe, Ni, and Zn).
[0030] The content rate of the positive electrode active material in the positive electrode active material layer of the present disclosure is not particularly limited, but may be 1% by mass or more, 5% by mass or more, 10% by mass or more, 15% by mass or more, or 20% by mass or more, and may be 50% by mass or less, 45% by mass or less, 40% by mass or less, 35% by mass or less, or 30% by mass or less.
[0031] The shape of the positive electrode active material is not particularly limited, and for example, it may be particulate. When the positive electrode active material is particulate, the particle diameter D of the positive electrode active material 50 may be, for example, 1 nm or more, 5 nm or more, or 10 nm or more, and may also be 500 μm or less, 100 μm or less, 50 μm or less, or 30 μm or less. The particle diameter D 50 is the particle diameter (median diameter) at the integrated value 50% in the volume-based particle size distribution determined by the laser diffraction / scattering method.
[0032] (Negative electrode active material layer) In the present disclosure, the negative electrode active material layer contains at least a negative electrode active material. Further, the negative electrode active material layer may further contain at least one of a solid electrolyte, a conductive assistant, and a binder, if necessary. The content rates of the solid electrolyte, the conductive assistant, and the binder optionally contained in the negative electrode active material layer are not particularly limited.
[0033] The material of the negative electrode active material is not particularly limited. As the negative electrode active material, for example, it may be metallic lithium or a material capable of occluding and releasing metal ions such as lithium ions. Examples of the material capable of occluding and releasing metal ions such as lithium ions include, but are not limited to, alloy-based negative electrode active materials, carbon materials, lithium titanate (Li4Ti5O 12 ) and the like.
[0034] The alloy-based anode active material is not particularly limited and includes, for example, Si alloy-based anode active materials or Sn alloy-based anode active materials. Si alloy-based anode active materials include silicon, silicon oxides, silicon carbides, silicon nitrides, etc., or solid solutions thereof. Si alloy-based anode active materials may also contain metallic elements other than silicon, such as iron (Fe), cobalt (Co), antimony (Sb), bismuth (Bi), lead (Pb), nickel (Ni), copper (Cu), zinc (Zn), germanium (Ge), indium (In), tin (Sn), titanium (Ti), etc. Sn alloy-based anode active materials include tin, tin oxides, tin nitrides, etc., or solid solutions thereof. Furthermore, the Sn alloy negative electrode active material may also contain other metallic elements besides tin, such as iron (Fe), cobalt (Co), antimony (Sb), bismuth (Bi), lead (Pb), nickel (Ni), copper (Cu), zinc (Zn), germanium (Ge), indium (In), tin (Sn), titanium (Ti), etc.
[0035] The carbon material is not particularly limited and examples include hard carbon, soft carbon, and graphite.
[0036] The content of the negative electrode active material in the negative electrode active material layer of this disclosure is not particularly limited, but may be 1% by mass or more, 5% by mass or more, 10% by mass or more, 15% by mass or more, or 20% by mass or more, and may be 50% by mass or less, 45% by mass or less, 40% by mass or less, 35% by mass or less, or 30% by mass or less.
[0037] The shape of the negative electrode active material is not particularly limited and may be particulate, for example. If the negative electrode active material is particulate, the particle size D of the negative electrode active material 50 For example, the particle size D may be 1 nm or more, 5 nm or more, or 10 nm or more, and may also be 500 μm or less, 100 μm or less, 50 μm or less, or 30 μm or less. 50 This is the particle diameter (median diameter) at 50% of the integrated value in the volume-based particle size distribution determined by laser diffraction and scattering.
[0038] (Separator layer) In this disclosure, the separator layer may be any separator layer commonly used in lithium-ion secondary batteries, such as those made of polyethylene (PE), polypropylene (PP), polyester, and polyamide resins. The separator layer may be a single-layer structure or a multi-layer structure. Examples of multi-layer separator layers include a two-layer PE / PP separator layer, or a three-layer PP / PE / PP or PE / PP / PE separator layer. The separator layer may also be made of a nonwoven fabric such as cellulose nonwoven fabric, resin nonwoven fabric, or glass fiber nonwoven fabric.
[0039] (Outer container) In this disclosure, the outer container houses the electrode stack inside.
[0040] In this disclosure, the material of the outer container is not particularly limited, but examples include metal, resin, and the like.
[0041] <Process (b)> In the method for manufacturing an electrode stack module according to this disclosure, a non-aqueous electrolyte is then injected into the electrode stack module precursor.
[0042] In this disclosure, the positive electrode active material layer contains ethylene carbonate before the injection of the electrolyte in step (b). The non-aqueous electrolyte injected in step (b) impregnates the positive electrode active material layer and the negative electrode active material layer, gradually dissolving the ethylene carbonate contained in the positive electrode active material layer. At this time, the concentration of ethylene carbonate in the non-aqueous electrolyte on the negative electrode active material layer side is lower than the concentration of ethylene carbonate in the non-aqueous electrolyte on the positive electrode active material layer side. That is, a concentration gradient of ethylene carbonate is formed in the non-aqueous electrolyte, thereby creating a concentration difference of ethylene carbonate between the non-aqueous electrolyte on the positive electrode active material layer side and the non-aqueous electrolyte on the negative electrode active material layer side.
[0043] Furthermore, in this disclosure, since the concentration of ethylene carbonate in the non-aqueous electrolyte on the negative electrode active material layer side is lower than the concentration of ethylene carbonate in the non-aqueous electrolyte on the positive electrode active material layer side, if the non-aqueous electrolyte contains vinylene carbonate, the concentration of vinylene carbonate in the non-aqueous electrolyte on the negative electrode active material layer side is higher than the concentration of vinylene carbonate in the non-aqueous electrolyte on the positive electrode active material layer side, and a concentration gradient of vinylene carbonate can be formed between the non-aqueous electrolyte on the positive electrode active material layer side and the non-aqueous electrolyte on the negative electrode active material layer side.
[0044] (Non-aqueous electrolyte) In this disclosure, a non-aqueous electrolyte is injected into an electrode stack module precursor.
[0045] In this disclosure, the non-aqueous electrolyte is not particularly limited, but for example, it is a liquid containing a solvent and a supporting salt. As the non-aqueous electrolyte, any known non-aqueous electrolyte for secondary batteries can be used. The non-aqueous electrolyte is not particularly limited, but one type may be used alone, or two or more types may be used in combination.
[0046] The solvent used in the non-aqueous electrolyte is not particularly limited as long as it is a non-aqueous solvent, but examples include cyclic carbonates and linear carbonates. Examples of cyclic carbonates include, but are not limited to, ethylene carbonate (EC), propylene carbonate (PC), butylene carbonate (BC), and vinylene carbonate (VC). Examples of linear carbonates include, but are not limited to, dimethyl carbonate (DMC), diethyl carbonate (DEC), and ethyl methyl carbonate (EMC). The solvent is not particularly limited, and may be used alone or in combination of two or more. When two or more solvents are used in combination, their content is not particularly limited.
[0047] Supporting salts for non-aqueous electrolytes are not particularly limited, but examples include lithium salts and sodium salts. Examples of lithium salts include inorganic lithium salts and organic lithium salts. Examples of inorganic lithium salts include LiPF6, LiBF4, LiClO4, and LiAsF6, but are not limited to these. Examples of organic lithium salts include LiCF3SO3, LiN(CF3SO2)2, LiN(C2F5SO2)2, LiN(FSO2)2, and LiC(CF3SO2)3, but are not limited to these. Examples of sodium salts include NaPF6, but are not limited to these.
[0048] <Process (c)> In the method for manufacturing an electrode stack module according to this disclosure, the electrode stack module precursor, into which the non-aqueous electrolyte has been injected, is then charged and discharged.
[0049] In this disclosure, during the charge-discharge process (c), the concentration of ethylene carbonate in the non-aqueous electrolyte on the negative electrode active material layer side is lower than the concentration of ethylene carbonate in the non-aqueous electrolyte on the positive electrode active material layer side. This makes it possible to suppress the formation of an ethylene carbonate-derived SEI film on the negative electrode active material layer.
[0050] In this disclosure, the non-aqueous electrolyte contains vinylene carbonate, and during the charge-discharge of step (c), the concentration of vinylene carbonate in the non-aqueous electrolyte on the negative electrode active material layer side may be higher than the concentration of vinylene carbonate in the non-aqueous electrolyte on the positive electrode active material layer side. This promotes the formation of a vinylene carbonate-derived SEI film on the negative electrode active material layer.
[0051] In this disclosure, the time between the injection of the non-aqueous electrolyte in step (b) and the charging and discharging in step (c) can be any value considering the size of the electrode stack. This time is not particularly limited, but is preferably short, and may be more than 0 hours, 1 hour or more, 2 hours or more, 3 hours or more, 5 hours or more, 7 hours or more, or 10 hours or more from the injection, and may be 24 hours or less, 20 hours or less, 15 hours or less, 13 hours or less, 10 hours or less, or 5 hours or less.
[0052] The present disclosure will be further described with reference to the following embodiments, but the scope of the present disclosure is not limited to these embodiments. [Examples]
[0053] <Example 1> (Provision of electrode stack module precursors) An electrode laminate comprising a positive electrode current collector layer, a positive electrode active material layer, a separator layer, a negative electrode active material layer, and a negative electrode current collector layer in this order, and an electrode laminate module precursor containing the electrode laminate within an outer container were prepared. In this case, as shown in Figure 3, the positive electrode active material layer of the electrode laminate had ethylene carbonate on the surface of the positive electrode active material layer on the separator layer side.
[0054] (Injection of non-aqueous electrolyte) An electrode stack module was prepared by injecting ethyl methyl carbonate and dimethyl carbonate as non-aqueous electrolytes into an electrode stack module precursor. The components of the non-aqueous electrolyte in the electrode stack module after injection were as follows: Ethylene carbonate: 25% by volume Ethyl methyl carbonate: 35% by volume Dimethyl carbonate: 40% by volume
[0055] (measurement) With the time immediately after injection of the non-aqueous electrolyte set as time 0, the electrode stack module was disassembled at 1 hour, 6 hours, and 24 hours of impregnation, and the concentration of ethylene carbonate in the non-aqueous electrolyte contained in the positive electrode active material layer was measured using GC-MS analysis.
[0056] (evaluation) Figure 4 shows the ethylene carbonate concentration in the non-aqueous electrolyte within the positive electrode active material layer as a function of impregnation time. The ethylene carbonate concentration decreased during the impregnation period from 0 to 10 hours, and remained constant after 10 hours. The decrease in ethylene carbonate concentration in the non-aqueous electrolyte within the positive electrode active material layer indicates that the ethylene carbonate concentration in the non-aqueous electrolyte within the positive electrode active material layer was higher than the total ethylene carbonate concentration in the non-aqueous electrolyte. This suggests that a concentration gradient of ethylene carbonate in the non-aqueous electrolyte was formed in the electrode stack during the impregnation period from 0 to 10 hours. Specifically, during the impregnation period from 0 to 10 hours, the ethylene carbonate concentration in the non-aqueous electrolyte on the negative electrode active material layer side was lower than the ethylene carbonate concentration in the non-aqueous electrolyte on the positive electrode active material layer side. [Explanation of Symbols]
[0057] 100 electrode stack 110 Positive electrode current collector layer 120 Cathode active material layer 130 Separator layer 140 Negative electrode active material layer 142 Negative electrode active material 144 Ethylene carbonate-derived SEI coating 146 SEI coating derived from vinylene carbonate 150 Negative electrode current collector layer 200 Ethylene carbonate 300 gas
Claims
1. (a) To provide an electrode stack module precursor comprising an electrode stack and an outer container, (b) Injecting a non-aqueous electrolyte into the electrode stack module precursor, (c) Charging and discharging the electrode laminate module precursor into which the non-aqueous electrolyte has been injected. Includes, The electrode laminate comprises a positive electrode active material layer, a separator layer, and a negative electrode active material layer in this order. The outer container houses the electrode stack inside, Before the injection of liquid in step (b), the positive electrode active material layer contains ethylene carbonate, and During the charging and discharging of step (c), the concentration of ethylene carbonate in the non-aqueous electrolyte on the negative electrode active material layer side is lower than the concentration of ethylene carbonate in the non-aqueous electrolyte on the positive electrode active material layer side. A method for manufacturing an electrode stack module.
2. The non-aqueous electrolyte contains vinylene carbonate, The method according to claim 1, wherein during the charging and discharging of step (c), the concentration of vinylene carbonate in the non-aqueous electrolyte on the negative electrode active material layer side is higher than the concentration of vinylene carbonate in the non-aqueous electrolyte on the positive electrode active material layer side.
3. The method according to claim 1, comprising preparing the positive electrode active material layer and the negative electrode active material layer by either wet powder deposition or dry deposition.
4. The method according to claim 1, wherein in step (a), the electrode laminate module precursor is provided at a temperature of 35°C or lower.