Collector, electrode, battery, manufacturing method of electrode, and manufacturing method of battery

Abstract

To provide a collector suitable for improving peel strength with the electrode layer.SOLUTION: A disclosed collector 100 includes a substrate 110 and a coating layer 120 that coats the substrate 110. In an example of the collector 100, the surface of the coating layer 120 has a stripe shape composed of recesses 12s and protrusions 12t, and in at least a portion of the surface on the coating layer side, the linear density of the protrusions 12t is greater than 2.5 / mm. The linear density of the protrusions 12t may be 6.8 / mm or less. In another example from collector 100, in at least a portion of the surface on the coating layer 120, the glossiness of the surface on the coating layer 120 side at an incident angle of 60 degrees is 19 or more and 60 or less. The coating layer 120 may include conductive carbon 12c and a first binder 12b.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a current collector, an electrode, a battery, a method for manufacturing an electrode, and a method for manufacturing a battery. [Background technology]

[0002] Current collectors are essential components in electrochemical devices such as batteries and capacitors. An electrode layer, such as an active material layer, is disposed on the current collector. The adhesion between the current collector and the electrode layer affects the performance of the electrochemical device. Current collectors with a substrate and a coating layer are known as current collectors that can improve adhesion.

[0003] Patent Documents 1 to 3 disclose current collectors having striped coating layers. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2014-199738 [Patent Document 2] Japanese Patent Application Laid-Open No. 2015-106525 [Patent Document 3] Japanese Patent Application Publication No. 2019-087489 Summary of the Invention [Problem to be solved by the invention]

[0005] An object of the present disclosure is to provide a current collector suitable for improving the peel strength from an electrode layer. [Means for solving the problem]

[0006] In one aspect, the present disclosure provides a method for manufacturing a semiconductor device comprising: A substrate; a coating layer that coats the substrate; Equipped with the surface on the coating layer side has a stripe shape composed of concave and convex portions on the surface, the linear density of the protrusions is greater than 2.5 / mm in at least a partial region of the surface on the coating layer side; A current collector is provided.

[0007] In another aspect, the present disclosure provides a method for manufacturing a semiconductor device comprising: A substrate; a coating layer that coats the substrate; Equipped with In at least a part of the surface on the coating layer side, the gloss of the surface on the coating layer side at an incident angle of 60 degrees is 19 or more and 60 or less. A current collector is provided. [Effects of the Invention]

[0008] According to the present disclosure, it is possible to provide a current collector suitable for improving the peel strength from an electrode layer. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a schematic cross-sectional view of a current collector according to the first embodiment. [Figure 2] FIG. 2 is a schematic diagram showing a method for measuring the glossiness of the surface of the current collector on the coating layer side. [Figure 3] FIG. 3 is a schematic cross-sectional view of an electrode according to the second embodiment. [Figure 4] FIG. 4 is a schematic cross-sectional view of a battery according to the third embodiment. [Figure 5] FIG. 5 is a schematic cross-sectional view of a battery according to the first modification. [Figure 6] FIG. 6 is a schematic cross-sectional view of a battery according to the second modification. [Figure 7A] FIG. 7A is a backscattered electron composition image of the surface of the current collector of Example 1-1. [Figure 7B] FIG. 7B is a backscattered electron composition image of the surface of the current collector of Example 1-2. [Figure 8A] FIG. 8A is a backscattered electron composition image of the surface of the current collector of Comparative Example 1-1. [Figure 8B]FIG. 8B is a backscattered electron composition image of the surface of the current collector of Comparative Example 1-2. [Figure 8C] FIG. 8C is a backscattered electron composition image of the surface of the current collector of Comparative Example 1-3. [Figure 8D] FIG. 8D is a backscattered electron composition image of the surface of the current collector of Comparative Example 1-4. [Figure 8E] FIG. 8E is a backscattered electron composition image of the surface of the current collector of Comparative Example 1-5. [Figure 9A] FIG. 9A is a graph showing the relationship between the gloss along the MD direction of the surface of the current collector at an incident angle of 60 degrees and the peel strength between the electrode layer and the current collector for the electrodes of Example 1-1, Example 1-2, and Comparative Examples 1-1 to 1-5. [Figure 9B] FIG. 9B is a graph showing the relationship between the gloss along the TD direction of the surface of the current collector at an incident angle of 60 degrees and the peel strength between the electrode layer and the current collector in the electrodes of Example 1-1, Example 1-2, and Comparative Examples 1-1 to 1-5. [Figure 10A] FIG. 10A is a backscattered electron composition image of the surface of the current collector of Example 2-1. [Figure 10B] FIG. 10B is a backscattered electron composition image of the surface of the current collector of Example 2-2. [Figure 10C] FIG. 10C is a backscattered electron composition image of the surface of the current collector of Example 2-3. [Figure 11] FIG. 11 is a backscattered electron composition image of the surface of the current collector of Comparative Example 2-1. [Figure 12] FIG. 12 is a graph showing the relationship between peel strength and electrode layer density in the electrodes of Examples 2-1 to 2-3 and Comparative Example 2-1. DETAILED DESCRIPTION OF THE INVENTION

[0010] (Findings that formed the basis of this disclosure) Improving the current collector is one way to improve the adhesion between the electrode layer and the current collector. The adhesion between the electrode layer and the current collector is based on the interaction between the electrode layer and the current collector. The inventors focused on the surface morphology of the coating layer of the current collector and attempted to improve the adhesion between the electrode layer and the current collector by improving the surface morphology of the coating layer, which led to the concept of the technology disclosed herein.

[0011] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. The present disclosure is not limited to the following embodiments.

[0012] (Embodiment 1) 1 is a schematic cross-sectional view of a current collector 100 according to embodiment 1. The current collector 100 includes a substrate 110 and a coating layer 120.

[0013] A coating layer 120 coats the substrate 110 .

[0014] In one example of the current collector 100 according to embodiment 1, the surface of the current collector 100 facing the coating layer 120 has a stripe shape composed of recesses 12s and protrusions 12t. The term "striped shape" refers to a shape in which the recesses 12s and protrusions 12t are alternately arranged in one direction when the surface of the current collector 100 facing the coating layer 120 is viewed from above. The recesses 12s are typically grooves extending in a predetermined direction on the surface of the current collector 100. The protrusions 12t are typically ridges extending in a predetermined direction. The recesses 12s and protrusions 12t may be branched or interrupted in plan view. The stripe shape may be formed over the entire surface of the current collector 100 facing the coating layer 120, or may be formed in a partial region of the surface facing the coating layer 120. The shape of the protrusions 12t is not particularly limited. The protrusions 12t may have a rectangular, trapezoidal, or triangular shape in cross section. In other words, the surface connecting the recesses 12s and the protrusions 12t may be perpendicular to the surface of the substrate 110 in a cross-sectional view, or may be inclined. The surface connecting the recesses 12s and the protrusions 12t may be linear or curved in a cross-sectional view. In the following, the "surface of the current collector 100" refers to the "surface of the current collector 100 on the coating layer 120 side."

[0015] In one example of the current collector 100 according to the first embodiment, the linear density of the stripe-shaped protrusions 12t is greater than 2.5 lines / mm in at least a portion of the surface on the coating layer 120 side. The linear density of the protrusions 12t may be 3.0 lines / mm or greater. As the linear density of the protrusions 12t increases, the spacing between the protrusions 12t decreases. If the linear density of the protrusions 12t is excessively large, the width of the recesses 12s is narrow. In this case, the electrode layer 130 and the substrate 110 are less likely to come into contact with each other, and the peel strength is likely to decrease. From this perspective, the upper limit of the linear density of the protrusions 12t is, for example, 6.8 lines / mm. The linear density of the protrusions 12t may be greater than 2.5 lines / mm and less than 6.8 lines / mm, or may be greater than 3.0 lines / mm and less than 6.0 lines / mm. The linear density of the protrusions 12t may satisfy the above range over the entire surface area formed in a stripe shape, or may satisfy the above range over a partial area of ​​the surface formed in a stripe shape.

[0016] The above configuration improves the peel strength between the current collector 100 and the electrode layer 130 (see FIG. 3) that can be formed on the coating layer 120 side of the current collector 100. Furthermore, the cycle characteristics of a battery including the current collector 100 can be improved.

[0017] In one example of the current collector 100 according to embodiment 1, the reason why the peel strength between the electrode layer 130 (see FIG. 3) and the current collector 100 is improved is not necessarily clear. For example, it is thought that the electrode layer 130 interacts with both the substrate 110 and the coating layer 120 that constitute the current collector 100, and therefore it is important to adjust the balance of these interactions. In the above example, it is thought that the balance of interactions can be adjusted by the linear density of the protrusions 12t. Examples of interactions include intermolecular forces.

[0018] The linear density of the stripe-shaped protrusions 12t is measured by the following method. First, a backscattered electron image of the surface of the current collector 100 is obtained using a scanning electron microscope (SEM). In the backscattered electron image, the protrusions 12t appear, for example, as dark areas (blackish areas) on a grayscale, and the recesses 12s appear, for example, as light areas (whitish areas) on a grayscale. When obtaining the backscattered electron image, the magnification is adjusted (for example, 50x) so that a 3.25 mm reference line can be drawn on the backscattered electron image, and the position and direction of the reference line are set so that the reference line intersects the most with the protrusions 12t. From the obtained backscattered electron image, the number of protrusions 12t intersecting the reference line is counted. Using the backscattered electron image makes it easier to see the recesses 12s and protrusions 12t as a contrast between light and dark, making it easier to count the number of protrusions (dark areas) 12t.

[0019] In another example of the current collector 100 according to the first embodiment, the glossiness G of the surface of the current collector 100 at an incident angle of 60 degrees is S (60 degrees) is 19 or more and 60 or less. Glossiness G S The gloss level G may be 19 or more and 50 or less, 19 or more and 40 or less, or 19 or more and 35 or less. S The surface of the current collector 100 may satisfy the above range over the entire surface, or may satisfy the above range in a partial region of the surface of the current collector 100.

[0020] The above configuration improves the peel strength between the current collector 100 and the electrode layer 130 (see FIG. 3) that can be formed on the coating layer 120 side of the current collector 100. Furthermore, the cycle characteristics of a battery including the current collector 100 can be improved.

[0021] FIG. 2 shows the glossiness G of the surface of the current collector 100. S Schematic diagram showing a method for measuring glossiness G S The measurement of glossiness G is carried out in a predetermined direction D (hereinafter referred to as "measurement direction D") when the surface of the current collector 100 is viewed in plan. Scan be calculated by making incident light L1 emitted from a light source Ls incident on the surface of the current collector 100 at an incident angle θ1 of 60 degrees, and measuring the luminous flux of reflected light L2 at a reflection angle θ2 of 60 degrees, which is equal to the incident angle θ1, with a photodetector Ld. Specifically, the surface of mirror glass with a refractive index of 1.567 is taken as the reference surface (reflectance: 10%), and the gloss of this reference surface is taken as 100. The luminous flux value of reflected light L2 of this reference surface at an incident angle θ1 of 60 degrees is taken as Φ 0S The luminous flux value on the surface of the current collector 100 at an incident angle θ1 of 60 degrees is Φ S Then, the gloss level G S can be calculated using the following formula:

[0022] G S =(Φ S / Φ 0S ) x 100

[0023] Glossiness G S In the measurement, a tungsten lamp is used as the light source Ls, and a photodiode, for example, is used as the photodetector Ld. S The gloss level G can be measured using the convergent light method (TAPPI method). S is measured, for example, by PG-1M manufactured by Nippon Denshoku Industries Co., Ltd.

[0024] Glossiness G S The measurement direction D is the MD direction (machine direction) or the TD direction (transverse direction). The "MD direction (machine direction)" refers to the direction in which the paint that will become the coating layer 120 is applied to the surface of the substrate 110. The "TD direction (transverse direction)" refers to the direction perpendicular to the MD direction and parallel to the surface of the substrate 110. That is, the gloss G S is the measured value when the MD direction (machine direction) is selected as the measurement direction D, or when the TD direction (transverse direction) is selected as the measurement direction D.

[0025] The current collector 100 can be used as an electrode for electrochemical devices such as non-aqueous electrolyte batteries, solid state batteries, capacitors, etc. The current collector 100 is particularly suitable as an electrode for all-solid state secondary batteries.

[0026] In addition, even in the example of the current collector 100 described above, the glossiness G of the surface of the current collector 100 at an incident angle of 60 degrees is S In one example of the current collector 100, the gloss G S may be 19 or more and 50 or less, 19 or more and 40 or less, or 19 or more and 35 or less. The area on the surface of the current collector 100 where the linear density of the protrusions 12t is within the above range has a gloss G S may be satisfied.

[0027] [Current collector] The current collector 100 includes a substrate 110 and a coating layer 120 .

[0028] The current collector 100 has, for example, a plate or foil shape. The thickness of the current collector 100 may be 0.1 μm to 1 mm, 1 μm to 100 μm, or 10 μm to 50 μm. When the thickness of the current collector 100 is 0.1 μm or more, the strength of the current collector 100 is improved, thereby suppressing breakage of the current collector 100. When the thickness of the current collector 100 is 1 mm or less, the weight of the current collector 100 is reduced, thereby improving the energy density of the electrochemical device. In other words, by appropriately adjusting the thickness of the current collector 100, electrochemical devices can be manufactured stably and the energy density of the electrochemical device can be improved.

[0029] The arithmetic mean roughness (Ra) of the surface of the current collector 100 may be 0.1 μm or more, 0.5 μm or more, 1.0 μm or more, or 1.2 μm or more. The upper limit of Ra may be 3.0 μm or 2.0 μm. When the surface of the current collector 100 has an Ra of 0.1 μm or more, the peel strength between the current collector 100 and the electrode layer 130 can be further improved when an electrode 1000 (see FIG. 3 ) composed of the current collector 100 and the electrode layer 130 is subjected to a press treatment. Ra may be 1.0 μm or more and 3.0 μm or less, 1.0 μm or more and 2.0 μm or less, or 1.0 μm or more and 1.5 μm or less. Ra may satisfy the above value over the entire surface of the current collector 100, or may satisfy the above value over a partial region of the surface of the current collector 100. The surface area of ​​the current collector 100 where the linear density of the protrusions 12t is within the above range may satisfy Ra within the above range, and the gloss G S The surface area of ​​the current collector 100 where Ra is within the above range may satisfy Ra within the above range.

[0030] The surface roughness in maximum height (Rz) of the current collector 100 may be 1.0 μm or more, 3.0 μm or more, or 5.0 μm or more. The upper limit of Rz may be 20 μm, 15 μm, or 10 μm. When the surface Rz of the current collector 100 is 1.0 μm or more, the peel strength between the current collector 100 and the electrode layer 130 can be further improved when an electrode 1000 (see FIG. 3 ) composed of the current collector 100 and the electrode layer 130 is subjected to a press treatment. Rz may be 1.0 μm or more and 20 μm or less, or 5.0 μm or more and 10 μm or less. Rz may satisfy the above value over the entire surface of the current collector 100, or may satisfy the above value only in a partial region of the surface of the current collector 100. The surface area of ​​the current collector 100 where the linear density of the protrusions 12t is within the above range may satisfy the Rz within the above range, and the gloss G S The surface area of ​​the current collector 100 where Rz is within the above range may satisfy the above range.

[0031] The arithmetic mean roughness (Ra) and maximum height roughness (Rz) of the surface of the current collector 100 are measured by the following method. First, a stylus-type profilometer is used to obtain a surface profile along the scanning direction of the surface of the current collector 100. The scanning direction is the same as the glossiness G S The measurement direction is the MD direction (machine direction) or the TD direction (transverse direction), the same as the measurement direction D in (1). The measurement conditions are, for example, as follows.

[0032] Stylus pressure: 1mg ·Measurement speed: 200μm / s Measurement length: 10mm ·Measurement interval: 0.4μm Leveling: Yes

[0033] As a stylus-type profilometer, for example, a P10 manufactured by KLA-Tencor Corporation can be used. Next, of the acquired surface profile, a range of 2 mm where the baseline is flat is analyzed to determine Ra and Rz of the surface of the current collector 100. This operation is performed three times, and the average values ​​are regarded as the arithmetic mean roughness (Ra) and maximum height roughness (Rz) of the surface of the current collector 100.

[0034] <Coating layer> The covering layer 120 may cover the entire main surface of the substrate 110, or may cover only a portion of the main surface of the substrate 110. The "main surface" refers to the surface of the substrate 110 having the largest area. The protrusions 12t may be formed from the covering layer 120, and the recesses 12s may be formed from the main surface of the substrate 110 exposed from the covering layer 120. Alternatively, the protrusions 12t may be thick portions of the covering layer 120, and the recesses 12s may be thin portions of the covering layer 120.

[0035] The coating layer 120 may contain the conductive carbon 12c, may contain the first binder 12b, or may contain both of them.

[0036] Examples of the conductive carbon 12c contained in the coating layer 120 include graphites such as natural graphite and artificial graphite, carbon blacks (CB) such as acetylene black (AB) and ketjen black (KB), conductive carbon fibers such as carbon fiber (CF), vapor-grown carbon, and carbon nanotubes (CNT), and nanocarbons such as graphene. As the conductive carbon, one conductive carbon selected from these may be used alone, or two or more conductive carbons selected from these may be used. The conductive carbon 12c contained in the coating layer 120 may include graphite and carbon black.

[0037] Examples of the first binder 12b contained in the coating layer 120 include polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE), polyethylene, polypropylene, aramid resin, polyamide, polyimide, polyamideimide, polyacrylonitrile, polyacrylic acid, polyacrylic acid methyl ester, polyacrylic acid ethyl ester, polyacrylic acid hexyl ester, polymethacrylic acid, polymethacrylic acid methyl ester (PMMA), polymethacrylic acid ethyl ester, polymethacrylic acid hexyl ester, polyvinyl acetate, polyvinylpyrrolidone, polyether, polycarbonate, polyethersulfone, polyetherketone, polyetheretherketone, polyphenylene sulfide, hexafluoropolypropylene, styrene butadiene rubber, carboxymethyl cellulose, and ethyl cellulose. The first binder 12b may be a copolymer synthesized using two or more monomers selected from the group consisting of tetrafluoroethylene, hexafluoroethylene, hexafluoropropylene, perfluoroalkyl vinyl ether, vinylidene fluoride, chlorotrifluoroethylene, ethylene, propylene, butadiene, isoprene, styrene, pentafluoropropylene, fluoromethyl vinyl ether, acrylic acid ester, acrylic acid, and hexadiene. As the first binder 12b, one selected from these may be used alone, or a mixture containing two or more selected from these may be used.

[0038] The first binder 12b contained in the coating layer 120 may be an aromatic super engineering plastic. The term "aromatic super engineering plastic" refers to an engineering plastic that contains an aromatic ring in its main chain and has a continuous usable temperature of 150°C or higher. Examples of aromatic super engineering plastics include polybenzimidazole (PBI), polyimide (PI), polyetherketoneetherketoneketone (PEKEKK), polyamideimide (PAI), polyetheretherketone (PEEK), polyetherketone (PEK), liquid crystal polymer (LCP), polyphenylene sulfide (PPS), polyethersulfone (PES), polyphenylsulfone (PPSU), polyetherimide (PEI), polysulfone (PSU), polyparaphenylene (PPP), and polyarylate (PAR). The first binder 12b may be a mixture containing two or more selected from these. Aromatic super engineering plastics exhibit high heat resistance. Therefore, when the coating layer 120 contains an aromatic super engineering plastic as the first binder 12b, the coating layer 120 is less likely to adhere to production equipment such as a press even when a member including the current collector 100 is compressed at high temperatures, thereby improving the productivity of electrochemical devices.

[0039] The first binder 12b may contain an additional binder other than the aromatic super engineering plastic. Alternatively, the first binder 12b may be the aromatic super engineering plastic. In other words, the first binder 12b may contain only the aromatic super engineering plastic.

[0040] Additional binders include the materials described above.

[0041] The additional binder may contain an elastomer from the viewpoint of excellent binding properties. Elastomer refers to a polymer having rubber elasticity. The elastomer used as the binder may be a thermoplastic elastomer or a thermosetting elastomer. Examples of elastomers include styrene-based elastomers described below, as well as butadiene rubber (BR), isoprene rubber (IR), chloroprene rubber (CR), acrylonitrile-butadiene rubber (NBR), hydrogenated isoprene rubber (HIR), hydrogenated butyl rubber (HIIR), hydrogenated nitrile rubber (HNBR), and acrylate butadiene rubber (ABR). A mixture containing two or more selected from these may also be used.

[0042] The first binder 12b may include at least one selected from the group consisting of polyimide (PI), polyethersulfone (PES), and polyvinylidene fluoride (PVDF).

[0043] Polyimides tend to exhibit higher heat resistance. Therefore, the use of polyimides effectively suppresses adhesion of the coating layer 120 to production equipment. As a result, the productivity of electrochemical devices is further improved. A soluble polyimide, which can be prepared as a polyimide solution in an organic solvent, may be used. Examples of organic solvents include N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, N-butyl-2-pyrrolidone, γ-butyrolactone, γ-valerolactone, 1,3-dimethylimidazolidinone, N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, methyl ethyl ketone, cyclohexanone, cyclopentanone, 3-methoxy-N,N-dimethylpropanamide, and 4-hydroxy-4-methyl-2-pentanone. Soluble polyimides are advantageous in terms of reducing the water content because they are easy to prepare polyimides with a high imidization rate.

[0044] Polyethersulfone tends to exhibit higher heat resistance, and therefore, the use of polyethersulfone can more effectively suppress adhesion of the coating layer 120 to production equipment, thereby further improving the productivity of electrochemical devices.

[0045] Polyvinylidene fluoride tends to exhibit high heat resistance and high chemical resistance. Therefore, the use of polyvinylidene fluoride can simultaneously suppress adhesion of the coating layer 120 to production equipment and suppress peeling between the substrate 110 and the coating layer 120 during the application of the electrode layer. As a result, the productivity of electrochemical devices is further improved.

[0046] The content of the first binder 12b in the coating layer 120 is not particularly limited and may be, for example, 1% by mass to 95% by mass, or alternatively 10% by mass to 80% by mass, or 30% by mass to 50% by mass. When the content of the first binder 12b in the coating layer 120 is 95% by mass or less, the electrical conductivity of the coating layer 120 is improved, thereby enabling the electrochemical device to have a higher output. When the content of the first binder 12b is 1% by mass or more, the presence of a sufficient amount of the first binder 12b and the like tends to suppress peeling of the coating layer 120.

[0047] The coating layer 120 may contain a conductive material other than the conductive carbon 12c. Examples of conductive materials other than conductive carbon include conductive fibers such as metal fibers, conductive powders such as carbon fluoride and aluminum, conductive whiskers such as zinc oxide and potassium titanate, conductive metal oxides such as titanium oxide, and conductive polymers such as polyaniline, polypyrrole, and polythiophene.

[0048] The coating layer 120 may contain elements or components other than the conductive carbon 12c and the first binder 12b. The other elements or components may be added to the coating layer 120 due to contamination or the like. For example, an unavoidable oxide film or the like may be formed on a portion of the surface of the coating layer 120. That is, the coating layer 120 may contain unavoidable oxides or the like.

[0049] The mass per unit area of ​​the coating layer 120 is not particularly limited, and is, for example, 0.01 g / m 2 More than 5g / m 2 It may be less than 0.1 g / m 2 More than 3g / m 2 It may be less than 0.5 g / m 2 More than 2g / m 2 The mass per unit area may be 0.01 g / m or less. 2 If the mass per unit area is 5 g / m or more, the contact area between the substrate 110 and the electrode layer 130 (see FIG. 3) can be reduced, thereby suppressing corrosion of the substrate 110. 2 If the temperature is equal to or lower than this, the electrical resistance of the coating layer 120 decreases, and the electrochemical device can be easily operated at high power.

[0050] The thickness of the coating layer 120 is not particularly limited and may be, for example, 0.001 μm to 10 μm, 0.01 μm to 5 μm, or 0.1 μm to 3 μm. When the thickness of the coating layer 120 is 0.001 μm or more, the contact area between the substrate 110 and the electrode layer can be reduced, thereby suppressing corrosion of the substrate 110. When the thickness of the coating layer 120 is 10 μm or less, the electrical resistance of the coating layer 120 is reduced, making it easier for the electrochemical device to operate at high power.

[0051] <Substrate> The substrate 110 has, for example, a foil or plate shape. The material of the substrate 110 may be a metal or an alloy. Examples of metals include aluminum, iron, nickel, and copper. Examples of alloys include aluminum alloys and stainless steel (SUS). The substrate 110 may contain aluminum or an aluminum alloy.

[0052] The substrate 110 may contain aluminum as a primary component. "The substrate 110 contains aluminum as a primary component" means that the aluminum content in the substrate 110 is 50% by mass or more. Aluminum is a lightweight metal with high electrical conductivity. Therefore, an electrode 1000 including a substrate 110 containing aluminum as a primary component can improve the mass energy density of an electrochemical device. The substrate 110 containing aluminum as a primary component may further contain elements other than aluminum. Note that if the substrate 110 is made only of aluminum, i.e., if the aluminum content in the substrate 110 is 100%, the strength of the substrate 110 may be reduced. Therefore, the substrate 110 may contain elements other than aluminum. The aluminum content in the substrate 110 may be 99% by mass or less, or may be 90% by mass or less.

[0053] The substrate 110 may contain an aluminum alloy. Aluminum alloys are lightweight and have high strength. Therefore, a current collector 100 including a substrate 110 containing an aluminum alloy can realize an electrochemical device that achieves both high mass energy density and high durability. The aluminum alloy is not particularly limited, and examples thereof include an Al-Cu alloy, an Al-Mn alloy, an Al-Mn-Cu alloy, and an Al-Fe-Cu alloy.

[0054] An Al-Mn alloy may be used as the material for the substrate 110. The Al-Mn alloy has high strength, as well as excellent formability and corrosion resistance. Therefore, a current collector 100 including a substrate 110 containing an Al-Mn alloy can improve the cycle characteristics of an electrochemical device.

[0055] The thickness of the substrate 110 is not particularly limited and may be, for example, 0.1 μm to 50 μm, or 1 μm to 30 μm. When the thickness of the substrate 110 is 0.1 μm or more, the strength of the substrate 110 is improved, and therefore damage to the substrate 110 is suppressed. When the thickness of the substrate 110 is 50 μm or less, the mass of the substrate 110 is reduced, and the mass energy density of the electrochemical device can be improved.

[0056] [Manufacturing method of current collector] The coating layer 120 can be produced by applying a solution or dispersion containing the material for the coating layer 120 to the surface of the substrate 110. The solution or dispersion can be applied using a gravure coater, a die coater, or the like. The current collector 100 may be produced by depositing the material for the coating layer 120 on the surface of the substrate 110 by a sputtering method or the like.

[0057] When it is desired to form the covering layer 120 in a striped shape, the covering layer 120 may be formed by a gravure coater using a striped plate from the viewpoint of controlling the striped shape.

[0058] (Embodiment 2) 3 is a schematic cross-sectional view of an electrode 1000 according to embodiment 2. The electrode 1000 includes a current collector 100 and an electrode layer 130. The current collector 100 is the current collector 100 according to embodiment 1 (see FIG. 1).

[0059] The electrode layer 130 is disposed on the current collector 100. The coating layer 120 of the current collector 100 is located between the substrate 110 and the electrode layer 130, and is in contact with both the substrate 110 and the electrode layer 130.

[0060] According to the above configuration, the peel strength between the electrode layer 130 and the current collector 100 is improved.

[0061] The electrode layer 130 may contain a solid electrolyte 13e, an active material 13a, or both. The electrode layer 130 may also contain a second binder 13b. The electrode 1000 is suitable for an electrochemical device, particularly a battery electrode, in which the electrode layer 130 contains at least one selected from the solid electrolyte 13e and the active material 13a.

[0062] <Solid electrolyte> The solid electrolyte 13e may include a sulfide solid electrolyte. The sulfide solid electrolyte may include lithium. By using a sulfide solid electrolyte containing lithium as the solid electrolyte 13e, a lithium secondary battery can be manufactured using the electrode 1000 including this sulfide solid electrolyte.

[0063] The solid electrolyte 13e may include a solid electrolyte other than a sulfide solid electrolyte, such as an oxide solid electrolyte, a halide solid electrolyte, a polymer solid electrolyte, or a complex hydride solid electrolyte. Alternatively, the solid electrolyte 13e may be a sulfide solid electrolyte. In other words, the solid electrolyte 13e may include only a sulfide solid electrolyte.

[0064] In the present disclosure, the term "oxide solid electrolyte" refers to a solid electrolyte containing oxygen. The oxide solid electrolyte may further contain anions other than sulfur and halogen elements as anions other than oxygen.

[0065] In the present disclosure, the term "halide solid electrolyte" refers to a solid electrolyte containing a halogen element but not containing sulfur. In the present disclosure, the term "sulfur-free solid electrolyte" refers to a solid electrolyte represented by a composition formula that does not contain sulfur. Therefore, a solid electrolyte containing only a trace amount of sulfur, for example, 0.1 mass % or less of sulfur, is included in the category of sulfur-free solid electrolyte. The halide solid electrolyte may further contain oxygen as an anion other than the halogen element.

[0066] Examples of sulfide solid electrolytes include Li2S-P2S5, Li2S-SiS2, Li2S-B2S3, Li2S-GeS2, and Li 3.25 Ge 0.25 P 0.75 S4, Li 10 GeP2S 12 These can be used in addition to LiX, Li2O, MO q , Li p MO q The element X in "LiX" is at least one selected from the group consisting of F, Cl, Br, and I. q " and "Li p MO q " element M is at least one selected from the group consisting of P, Si, Ge, B, Al, Ga, In, Fe, and Zn. q " and "Li p MO q In the above formula, p and q are each independently a natural number. The sulfide solid electrolyte may be a glass ceramic type or an argyrodite type.

[0067] As the sulfide solid electrolyte, for example, Li2S-P2S5-based glass ceramics may be used. Li2S-P2S5-based glass ceramics include LiX, Li2O, MO q , Li p MO q Alternatively, two or more selected from LiCl, LiBr, and LiI may be added. Since Li2S-P2S5-based glass ceramics are relatively soft materials, an electrode 1000 containing Li2S-P2S5-based glass ceramics can be used to manufacture a highly durable battery.

[0068] Examples of oxide solid electrolytes include NASICON-type solid electrolytes, such as LiTi2(PO4)3 and its elemental substitution products, (LaLi)TiO3-based perovskite-type solid electrolytes, and Li 14 ZnGeO 16 , Li4SiO4, LiGeO4 and their element-substituted LISICON-type solid electrolytes, Li7La3Zr2O12 Garnet-type solid electrolytes, such as those substituted with LiPO4 and its N-substituted compounds, and glasses and glass ceramics based on Li-BO compounds such as LiBO2 and LiBO3, to which LiSO4, LiCO3, etc. are added, can be used.

[0069] The halide solid electrolyte contains, for example, Li, M1, and X. M1 is at least one selected from the group consisting of metal elements and metalloid elements other than Li. X is at least one selected from the group consisting of F, Cl, Br, and I. The halide solid electrolyte has high thermal stability, which can improve the safety of the battery. Furthermore, the halide solid electrolyte does not contain sulfur, which can suppress the generation of hydrogen sulfide gas.

[0070] In the present disclosure, "metalloid elements" are B, Si, Ge, As, Sb and Te.

[0071] In this disclosure, "metal element" refers to all elements in Groups 1 to 12 of the Periodic Table excluding hydrogen, and all elements in Groups 13 to 16 of the Periodic Table excluding B, Si, Ge, As, Sb, Te, C, N, P, O, S, and Se.

[0072] That is, in the present disclosure, "metalloid elements" and "metal elements" are a group of elements that can become cations when forming an inorganic compound with a halogen element.

[0073] For example, the halide solid electrolyte may be a material represented by the following composition formula (1). Li α M1 β X γ ...Equation (1)

[0074] In the above composition formula (1), α, β, and γ are each independently a value greater than 0. γ can be 4, 6, or the like.

[0075] The above configuration improves the ionic conductivity of the halide solid electrolyte, thereby improving the ionic conductivity of the electrode 1000. When the electrode 1000 is used in a battery, it can further improve the cycle characteristics of the battery.

[0076] In the above composition formula (1), the element M1 may contain Y (=yttrium), that is, the halide solid electrolyte may contain Y as a metal element.

[0077] The halide solid electrolyte containing Y may be represented by, for example, the following composition formula (2). Li a Me b Y c X6...Formula (2)

[0078] In formula (2), a, b, and c may satisfy a+mb+3c=6 and c>0. The element Me is at least one selected from the group consisting of metal elements and metalloid elements other than Li and Y. m represents the valence of the element Me. When the element Me contains multiple elements, mb is the sum of the products of the composition ratios of each element and the valences of the elements. For example, when Me contains the element Me1 and the element Me2, and the composition ratio of the element Me1 is b1, the valence of the element Me1 is m1, the composition ratio of the element Me2 is b2, and the valence of the element Me2 is m2, mb is expressed as m1·b1+m2·b2. In the above composition formula (2), the element X is at least one selected from the group consisting of F, Cl, Br, and I.

[0079] The element Me may be, for example, at least one selected from the group consisting of Mg, Ca, Sr, Ba, Zn, Sc, Al, Ga, Bi, Zr, Hf, Ti, Sn, Ta, Gd, and Nb.

[0080] For example, the following materials can be used as the halide solid electrolyte: The following materials can further improve the ionic conductivity of the solid electrolyte 13e, thereby further improving the output characteristics of the battery.

[0081] The halide solid electrolyte may be a material represented by the following composition formula (A1). Li 6-3d Y d X6 ··· Formula (A1)

[0082] In the composition formula (A1), the element X is at least one selected from the group consisting of Cl, Br, and I. In the composition formula (A1), d satisfies 0 < d < 2.

[0083] The halide solid electrolyte may be a material represented by the following composition formula (A2). Li3YX6 ··· Formula (A2)

[0084] In the composition formula (A2), the element X is at least one selected from the group consisting of Cl, Br, and I.

[0085] The halide solid electrolyte may be a material represented by the following composition formula (A3). Li 3-3δ Y 1+δ Cl6 ··· Formula (A3)

[0086] In the composition formula (A3), δ satisfies 0 < δ ≤ 0.15.

[0087] The halide solid electrolyte may be a material represented by the following composition formula (A4). Li 3-3δ Y 1+δ Br6 ··· Formula (A4)

[0088] In the composition formula (A4), δ satisfies 0 < δ ≤ 0.25.

[0089] The halide solid electrolyte may be a material represented by the following composition formula (A5). Li 3-3δ-a Y 1+δ-a Me a Cl 6-x-y Br x I y ··· Formula (A5)

[0090] In the above compositional formula (A5), the element Me is at least one selected from the group consisting of Zr, Hf, and Ti.

[0091] Furthermore, in the above compositional formula (A5), -1 < δ < 1, 0 ≤ a < 1.5, 0 < (3 - 3δ - a), 0 < (1 + δ - a), 0 ≤ x ≤ 6, 0 ≤ y ≤ 6, and (x + y) ≤ 6, are satisfied.

[0092] The halide solid electrolyte may be a compound containing Li, M2, X2, and O (oxygen). The element M2 includes, for example, at least one selected from the group consisting of Nb and Ta. Also, X2 is at least one selected from the group consisting of F, Cl, Br, and I.

[0093] The compound containing Li, M2, X2, and O (oxygen) may be represented by, for example, the compositional formula: Li x M2O y X2 5+x-2y Here, x may satisfy 0.1 < x < 7.0. y may satisfy 0.4 < y < 1.9.

[0094] More specifically, as the halide solid electrolyte, for example, Li3Y(Cl,Br,I)6, Li 2.7 Y 1.1 (Cl,Br,I)6, Li2Mg(F,Cl,Br,I)4, Li2Fe(F,Cl,Br,I)4, Li(Al,Ga,In)(F,Cl,Br,I)4, Li3(Al,Ga,In)(F,Cl,Br,I)6, Li3(Ca,Y,Gd)(Cl,Br,I)6, Li 2.7 (Ti,Al)F6, Li 2.5(Ti,Al)F6, Li(Ta,Nb)O(F,Cl)4, etc. can be used. In this disclosure, when an element in a formula is expressed as "(Al,Ga,In)", this notation indicates at least one element selected from the group of elements in parentheses. In other words, "(Al,Ga,In)" is synonymous with "at least one selected from the group consisting of Al, Ga, and In". The same applies to other elements.

[0095] As the polymer solid electrolyte, for example, a compound of a polymer compound and a lithium salt can be used. The polymer compound may have an ethylene oxide structure. A polymer compound having an ethylene oxide structure can contain a large amount of lithium salt. Therefore, ionic conductivity can be further improved. As the lithium salt, LiPF6, LiBF4, LiSbF6, LiAsF6, LiSO3CF3, LiN(SO2F)2, LiN(SO2CF3)2, LiN(SO2C2F5)2, LiN(SO2CF3)(SO2C4F9), LiC(SO2CF3)3, etc. can be used. One lithium salt may be used alone, or two or more lithium salts may be used in combination.

[0096] As the complex hydride solid electrolyte, for example, LiBH4-LiI, LiBH4-P2S5, etc. can be used.

[0097] The shape of the solid electrolyte 13e is not particularly limited and may be needle-like, spherical, oval-spherical, etc. The shape of the solid electrolyte 13e may be particulate.

[0098] When the solid electrolyte 13e is particulate (e.g., spherical), the median diameter of the solid electrolyte 13e may be 0.1 μm or more and 5 μm or less, or 0.5 μm or more and 3 μm or less. When the median diameter of the solid electrolyte 13e is 0.1 μm or more, the dispersibility of the electrode composition (slurry) used to manufacture the electrode 1000 is improved, and the electrode 1000 may have a denser structure. When the median diameter of the solid electrolyte 13e is 5 μm or less, the electrode 1000 may have high surface smoothness and a denser structure.

[0099] The median diameter refers to the particle size at which the cumulative volume in the volume-based particle size distribution is equal to 50%. The volume-based particle size distribution is determined by a laser diffraction scattering method. The same applies to the other materials listed below.

[0100] The specific surface area of ​​the solid electrolyte 13e is 0.1m 2 / g or more 100m 2 / g or less, and 2 / g or more 10m 2 The specific surface area of ​​the solid electrolyte 13e may be 0.1 m / g or less. 2 / g or more 100m 2 / g or less, the dispersibility of the electrode composition (slurry) used to manufacture the electrode 1000 is improved, and the electrode 1000 may have a denser structure. The specific surface area can be measured by the BET multipoint method using a gas adsorption measurement device.

[0101] The ionic conductivity of solid electrolyte 13e is 0.01 mS / cm 2 It may be 0.1 mS / cm or more. 2 It may be 1 mS / cm or more. 2 The ionic conductivity of the solid electrolyte 13e may be 0.01 mS / cm or more. 2 In this case, the output characteristics of the battery can be improved.

[0102] <Active material> The active material 13a includes a material that has the property of absorbing and releasing metal ions (e.g., lithium ions). The active material 13a includes, for example, a positive electrode active material or a negative electrode active material. When the electrode 1000 includes the active material 13a, the electrode 1000 can be used to manufacture a lithium secondary battery.

[0103] The active material 13a includes, for example, a material having the property of absorbing and releasing metal ions (e.g., lithium ions) as a positive electrode active material. Examples of the positive electrode active material include transition metal oxides, transition metal fluorides, polyanionic materials, fluorinated polyanionic materials, transition metal sulfides, transition metal oxysulfides, transition metal oxynitrides, and lithium-containing compounds thereof. Examples of lithium-containing transition metal oxides include Li(NiCoAl)O2, Li(NiCoMn)O2, and LiCoO2. When a lithium-containing transition metal oxide is used as the positive electrode active material, the manufacturing cost of the electrode 1000 can be reduced and the average discharge voltage of the battery can be improved. Li(NiCoAl)O2 means that Ni, Co, and Al are contained in any ratio. Li(NiCoMn)O2 means that Ni, Co, and Mn are contained in any ratio.

[0104] The median diameter of the positive electrode active material may be 0.1 μm or more and 100 μm or less, or 1 μm or more and 10 μm or less. When the median diameter of the positive electrode active material is 0.1 μm or more, the active material 13a and the solid electrolyte 13e can be well dispersed in the electrode 1000. This improves the charge / discharge characteristics of the battery. When the median diameter of the positive electrode active material is 100 μm or less, the lithium diffusion rate within the positive electrode active material improves. This allows the battery to operate at high power.

[0105] The active material 13a includes, for example, a negative electrode active material having the property of absorbing and releasing metal ions (e.g., lithium ions). Examples of the negative electrode active material include metal materials, carbon materials, oxides, nitrides, tin compounds, and silicon compounds. The metal material may be a single metal or an alloy. Examples of the metal material include lithium metal and lithium alloys. Examples of the carbon material include natural graphite, coke, partially graphitized carbon, carbon fiber, spherical carbon, artificial graphite, and amorphous carbon. The use of silicon (Si), tin (Sn), silicon compounds, tin compounds, and the like can improve the capacity density of the battery. The use of an oxide compound containing titanium (Ti) or niobium (Nb) can improve the safety of the battery.

[0106] The median diameter of the negative electrode active material may be 0.1 μm or more and 100 μm or less, or 1 μm or more and 10 μm or less. When the median diameter of the negative electrode active material is 0.1 μm or more, the active material 13a and the solid electrolyte 13e can be well dispersed in the electrode 1000. This improves the charge / discharge characteristics of the battery. When the median diameter of the negative electrode active material is 100 μm or less, the lithium diffusion rate within the negative electrode active material improves. This allows the battery to operate at high power.

[0107] The positive electrode active material and the negative electrode active material may be coated with a coating material to reduce the interfacial resistance between each active material and the solid electrolyte. That is, a coating layer may be provided on the surface of the positive electrode active material and the negative electrode active material. The coating layer is a layer containing a coating material. A material with low electronic conductivity may be used as the coating material used for the coating layer. The coating material used for the coating layer may be an oxide material, an oxide solid electrolyte, a halide solid electrolyte, a sulfide solid electrolyte, or the like. The positive electrode active material and the negative electrode active material may be coated with only one coating material selected from the above-mentioned materials. That is, the coating layer may be formed of only one coating material selected from the above-mentioned materials. Alternatively, two or more coating layers may be provided using two or more coating materials selected from the above-mentioned materials.

[0108] Examples of oxide materials used as the coating material for the coating layer include SiO2, Al2O3, TiO2, B2O3, Nb2O5, WO3, and ZrO2.

[0109] The oxide solid electrolyte used as the coating material for the coating layer may be any of the oxide solid electrolytes exemplified above. Examples of the oxide solid electrolyte used as the coating material for the coating layer include Li-Nb-O compounds such as LiNbO3, Li-BO compounds such as LiBO2 and Li3BO3, Li-Al-O compounds such as LiAlO2, Li-Si-O compounds such as Li4SiO4, Li-SO compounds such as Li2SO4, and Li4Ti5O. 12Examples of oxide solid electrolytes include Li-Ti-O compounds such as Li2ZrO3, Li-Zr-O compounds such as Li2MoO3, Li-VO compounds such as LiV2O5, Li-WO compounds such as Li2WO4, and Li-PO compounds such as LiPO4. Oxide solid electrolytes have high potential stability. Therefore, using oxide solid electrolytes as coating materials can further improve the cycle characteristics of batteries.

[0110] The halide solid electrolyte used in the coating material of the coating layer may be any of the halide solid electrolytes exemplified above. Examples of the halide solid electrolyte used in the coating material of the coating layer include Li-Y-Cl compounds such as LiYCl6, Li-Y-Br-Cl compounds such as LiYBr2Cl4, Li-Ta-O-Cl compounds such as LiTaOCl4, and Li 2.7 Ti 0.3 Al 0.7 Examples of suitable solid electrolytes include Li-Ti-Al-F compounds such as F6. Halide solid electrolytes have high ionic conductivity and high potential stability. Therefore, the use of halide solid electrolytes as coating materials can further improve the cycle characteristics of batteries.

[0111] The sulfide solid electrolyte used as the coating material of the coating layer may be any of the sulfide solid electrolytes exemplified above. Examples of sulfide solid electrolytes used as the coating material of the coating layer include Li-PS compounds such as Li2S-P2S5. Sulfide solid electrolytes have high ionic conductivity and a low Young's modulus. Therefore, by using a sulfide solid electrolyte as the coating material, a uniform coating can be achieved, and the cycle characteristics of the battery can be further improved.

[0112] <Second binder> The second binder 13b can improve the adhesiveness between particles of the solid electrolyte 13e and the active material 13a in the electrode 1000. The second binder 13b can also improve the adhesiveness between the electrode layer 130 and the current collector 100 in the electrode 1000. The additional binder described in the first embodiment can be used as the second binder 13b.

[0113] The second binder 13b may contain a styrene-based elastomer. A styrene-based elastomer refers to an elastomer containing repeating units derived from styrene. The repeating units refer to molecular structures derived from monomers and are sometimes called constituent units. Styrene-based elastomers are suitable as binders for the electrode 1000 because of their excellent flexibility and elasticity. The content of repeating units derived from styrene in the styrene-based elastomer is not particularly limited, and is, for example, 5% by mass or more and 70% by mass or less.

[0114] The styrene-based elastomer may be a block copolymer containing a first block composed of repeating units derived from styrene and a second block composed of repeating units derived from a conjugated diene. Examples of conjugated dienes include butadiene and isoprene. The repeating units derived from the conjugated diene may be hydrogenated. That is, the repeating units derived from the conjugated diene may or may not have an unsaturated bond such as a carbon-carbon double bond. The block copolymer may have a triblock arrangement composed of two first blocks and one second block. The block copolymer may be an ABA triblock copolymer. In this triblock copolymer, the A block corresponds to the first block and the B block corresponds to the second block. The first block functions, for example, as a hard segment. The second block functions, for example, as a soft segment.

[0115] Examples of styrene-based elastomers include styrene-ethylene / butylene-styrene block copolymer (SEBS), styrene-ethylene / propylene-styrene block copolymer (SEPS), styrene-ethylene / ethylene / propylene-styrene block copolymer (SEEPS), styrene-butadiene rubber (SBR), styrene-butadiene-styrene block copolymer (SBS), styrene-isoprene-styrene block copolymer (SIS), and hydrogenated styrene-butadiene rubber (HSBR). The second binder 13b may contain at least one styrene-based elastomer selected from the group consisting of SBR and SEBS. A mixture containing two or more selected from these may also be used as the second binder 13b. Styrene-based elastomers have excellent flexibility and elasticity, making them suitable as binders for the electrode layer 130.

[0116] The styrene-based elastomer may be a styrene-based triblock copolymer. Examples of the styrene-based triblock copolymer include styrene-ethylene / butylene-styrene block copolymer (SEBS), styrene-ethylene / propylene-styrene block copolymer (SEPS), styrene-ethylene / ethylene / propylene-styrene block copolymer (SEEPS), styrene-butadiene-styrene block copolymer (SBS), and styrene-isoprene-styrene block copolymer (SIS). These styrene-based triblock copolymers are sometimes called styrene-based thermoplastic elastomers. These styrene-based triblock copolymers tend to be flexible and have high strength.

[0117] The styrene-based elastomer may include a styrene-ethylene / butylene-styrene block copolymer (SEBS). SEBS has excellent flexibility and elasticity, and excellent packing properties during thermal compression, making it particularly suitable as a binder for the electrode layer 130.

[0118] The styrene-based elastomer may contain a modifying group. The modifying group refers to a functional group that chemically modifies all repeating units in the polymer chain, some repeating units in the polymer chain, or the terminal portion of the polymer chain. The modifying group can be introduced into the polymer chain by substitution reaction, addition reaction, or other methods. Examples of the modifying group include elements with relatively high electronegativity, such as O, N, S, F, Cl, Br, and F, and elements with relatively low electronegativity, such as Si, Sn, and P. Modifying groups containing such elements can impart polarity to the polymer. Examples of the modifying group include carboxylic acid groups, acid anhydride groups, acyl groups, hydroxy groups, sulfo groups, sulfanyl groups, phosphate groups, phosphonate groups, isocyanate groups, epoxy groups, silyl groups, amino groups, nitrile groups, and nitro groups. An example of an acid anhydride group is maleic anhydride. The modifying group may also be a functional group that can be introduced by reacting the following compounds with a modifying agent: Examples of the modifying compound include epoxy compounds, ether compounds, ester compounds, isocyanate compounds, isothiocyanate compounds, isocyanuric acid derivatives, nitrogen-containing carbonyl compounds, nitrogen-containing vinyl compounds, nitrogen-containing epoxy compounds, mercapto group derivatives, thiocarbonyl compounds, halogenated silicon compounds, epoxylated silicon compounds, vinylated silicon compounds, alkoxy silicon compounds, nitrogen-containing alkoxy silicon compounds, halogenated tin compounds, organotin carboxylate compounds, phosphite ester compounds, and phosphino compounds. When the styrene-based elastomer in the second binder 13b contains the above-described modifying group, the interaction with the current collector 100 can improve the peel strength between the electrode layer 130 and the current collector 100.

[0119] The styrene-based elastomer may contain a modifying group having a nitrogen atom. The modifying group having a nitrogen atom is a nitrogen-containing functional group, such as an amino group such as an amine compound. The modifying group may be located at the end of the polymer chain. The styrene-based elastomer may be, for example, a terminal amine-modified styrene-based elastomer. The styrene-based elastomer may be, for example, a styrene-based elastomer having a nitrogen atom at at least one end of the polymer chain and a star-shaped polymer structure centered on a nitrogen-containing alkoxysilane substituent.

[0120] The styrene-based elastomer may contain at least one selected from the group consisting of modified SBR and modified SEBS. Modified SBR and modified SEBS have excellent flexibility and elasticity and are suitable as binders for the electrode layer 130. Therefore, an electrode 1000 using modified SBR and modified SEBS can improve the peel strength between the electrode layer 130 and the current collector 100.

[0121] Weight average molecular weight (M w) may be 200,000 or more. The weight-average molecular weight of the styrene-based elastomer may be 300,000 or more, 500,000 or more, 800,000 or more, or 1,000,000 or more. The upper limit of the weight-average molecular weight is, for example, 1,500,000. When the weight-average molecular weight of the styrene-based elastomer is 200,000 or more, the particles of the solid electrolyte 13e and the active material 13a can be bonded to each other with sufficient adhesive strength. When the weight-average molecular weight of the styrene-based elastomer is 1,500,000 or less, ion conduction between the particles of the solid electrolyte 13e is less likely to be inhibited by the second binder 13b, thereby improving the output characteristics of the battery. The weight-average molecular weight of the styrene-based elastomer can be determined, for example, by gel permeation chromatography (GPC) measurement using polystyrene as a standard sample. In other words, the weight-average molecular weight is a value converted into polystyrene. In the GPC measurement, chloroform may be used as an eluent. When two or more peak tops are observed in the chart obtained by the GPC measurement, the weight average molecular weight calculated from the entire peak range including each peak top can be regarded as the weight average molecular weight of the styrene-based elastomer.

[0122] In a styrene-based elastomer, the ratio of the degree of polymerization m of the repeating unit derived from styrene to the degree of polymerization n of the repeating unit derived from a substance other than styrene is defined as m:n. In this case, the molar fraction (φ) of the repeating unit derived from styrene in a styrene-based elastomer can be calculated by φ=m / (m+n). The molar fraction (φ) of the repeating unit derived from styrene in a styrene-based elastomer can be determined, for example, by proton nuclear magnetic resonance ( 1 It can be determined by H-NMR measurement.

[0123] In the styrene-based elastomer, the molar fraction (φ) of repeating units derived from styrene may be 0.02 or more and 0.55 or less, or 0.1 or more and 0.3 or less. When the molar fraction (φ) of the styrene-based elastomer is 0.02 or more, the strength of the electrode layer 130 can be improved. When the molar fraction (φ) of the styrene-based elastomer is 0.55 or less, the flexibility of the electrode layer 130 can be improved.

[0124] The second binder 13b may contain a binder other than a styrene-based elastomer. Alternatively, the second binder 13b may be a styrene-based elastomer. In other words, the second binder 13b may contain only a styrene-based elastomer.

[0125] <Electrode layer> The electrode layer 130 may contain a solid electrolyte 13e, an active material 13a, or both. The electrode layer 130 may further contain a second binder 13b. With this configuration, the electrode layer 130 maintains sufficient strength while improving the ionic conductivity within the electrode layer 130, enabling the battery to operate at high power.

[0126] The median diameter of the solid electrolyte 13e contained in the electrode layer 130 may be smaller than the median diameter of the active material 13a, which allows the solid electrolyte 13e and the active material 13a to be dispersed well.

[0127] In the electrode layer 130, the volume ratio "v1:100-v1" of the active material 13a to the solid electrolyte 13e may satisfy 30≦v1≦95. v1 indicates the volume ratio of the active material 13a when the total volume of the active material 13a and the solid electrolyte 13e contained in the electrode layer 130 is regarded as 100. When 30≦v1 is satisfied, the battery can easily ensure sufficient energy density. When v1≦95 is satisfied, the battery can more easily operate at high output.

[0128] The thickness of the electrode layer 130 may be 10 μm or more and 500 μm or less. When the thickness of the electrode layer 130 is 10 μm or more, a sufficient energy density can be easily ensured for the battery. When the thickness of the electrode layer 130 is 500 μm or less, a battery including the electrode layer 130 can operate at high power.

[0129] In the electrode layer 130, the ratio of the second binder 13b to the solid electrolyte 13e may be 0.1% by mass or more and 10% by mass or less, 0.5% by mass or more and 8% by mass or less, or 1% by mass or more and 5% by mass or less. When the ratio of the second binder 13b to the solid electrolyte 13e is 0.1% by mass or more, the second binder 13b tends to bind more particles of the solid electrolyte 13e together. This can improve the film strength of the electrode layer 130. When the ratio of the second binder 13b to the solid electrolyte 13e is 10% by mass or less, the contact between particles of the solid electrolyte 13e in the electrode layer 130 tends to improve. This can improve the ionic conductivity of the electrode layer 130.

[0130] In the electrode layer 130, the ratio of the second binder 13b to the active material 13a may be 0.03% by mass or more and 4% by mass or less, 0.15% by mass or more and 2% by mass or less, or 0.3% by mass or more and 1% by mass or less. When the ratio of the second binder 13b to the active material 13a is 0.03% by mass or more, the second binder 13b tends to bind more particles of the active material 13a together. This can improve the film strength of the electrode layer 130. When the ratio of the second binder 13b to the active material 13a is 4% by mass or less, the contact between particles of the active material 13a in the electrode layer 130 tends to improve. This can improve the output characteristics of the battery.

[0131] The electrode layer 130 may further contain a conductive additive for the purpose of improving electronic conductivity. Examples of the conductive additive include graphites such as natural graphite and artificial graphite, carbon blacks such as acetylene black and ketjen black, conductive fibers such as carbon fiber and metal fiber, conductive powders such as carbon fluoride and aluminum, conductive whiskers such as zinc oxide and potassium titanate, conductive metal oxides such as titanium oxide, and conductive polymers such as polyaniline, polypyrrole, and polythiophene. Using a carbon material as the conductive additive can reduce costs.

[0132] The electrode layer 130 may contain a dispersant to improve the dispersibility of the solid electrolyte 13e and the active material 13a. The dispersant may be a low-molecular-weight dispersant or a high-molecular-weight dispersant. For example, a commercially available dispersant, wetting agent, or surfactant may be used as the dispersant.

[0133] In the electrode layer 130, the dispersant may include an amine compound. The amine compound is suitable for improving the dispersibility of the solid electrolyte 13e. Examples of the amine compound include aliphatic amines such as methylamine and dimethylamine, aromatic amines such as aniline, and heterocyclic amines such as imidazole and imidazoline.

[0134] In the electrode layer 130, the dispersant may include imidazoline or an imidazoline derivative. The imidazoline or imidazoline derivative is more suitable for improving the dispersibility of the solid electrolyte 13e. Examples of imidazoline derivatives include 1-hydroxyethyl-2-alkenylimidazoline.

[0135] In the electrode layer 130, the mass ratio of the dispersant to the mass of the solid electrolyte 13e is not particularly limited and may be, for example, 0.001 mass% to 10 mass% or less, such as 0.01 mass% to 1.0 mass%. When the mass ratio of the dispersant is 0.001 mass% or more, the dispersibility of the solid electrolyte 13e in the electrode layer 130 can be improved. When the mass ratio of the dispersant is 10 mass% or less, a decrease in the ionic conductivity of the solid electrolyte 13e can be suppressed.

[0136] [Electrode manufacturing method] The electrode 1000 can be manufactured by, for example, the following method. First, an electrode composition for forming the electrode layer 130 is prepared. The electrode composition may contain the solid electrolyte 13e, the active material 13a, or both. The electrode composition may further contain a solvent (first solvent). The electrode composition may be a dispersion (slurry) in which the solid electrolyte 13e, the active material 13a, and the second binder 13b are dispersed in a solvent. The solvent may be a solvent that does not react with the solid electrolyte 13e, such as an aromatic hydrocarbon solvent such as tetralin. Next, the electrode composition is applied to the surface of the current collector 100 facing the coating layer 102 to form a coating film (first coating film). Examples of methods for applying the electrode composition include die coating, gravure coating, doctor blade coating, bar coating, spray coating, and electrostatic coating. After the coating film is formed, the solvent may be removed from the coating film. Specifically, the solvent can be removed from the coating film by drying the resulting coating film. In this way, the electrode layer 130 is formed, and the electrode 1000 can be obtained.

[0137] After the solvent is removed, the coating film may be subjected to a press treatment (first press treatment). By performing a press treatment on the coating film, filling of the material of the electrode layer 130 is promoted. For example, a roll press, a plate press, or an isostatic press (ISP) may be used for the press treatment of the coating film. The press treatment may be performed with a pressure that does not cause warping of the electrode 1000. By performing a press treatment on the coating film, the peel strength between the electrode layer 130 and the current collector 100 can be further improved.

[0138] (Embodiment 3) 4 is a schematic cross-sectional view of a battery 2000 according to Embodiment 3. The battery 2000 includes an anode 200, a cathode 400, and an electrolyte layer 300.

[0139] At least one selected from the group consisting of the negative electrode 200 and the positive electrode 400 includes the electrode 1000 according to embodiment 2. That is, at least one selected from the group consisting of the negative electrode 200 and the positive electrode 400 includes an electrode layer 130 and a current collector 100.

[0140] The electrolyte layer 300 is located between the negative electrode 200 and the positive electrode 400 .

[0141] According to the above configuration, the output characteristics of the battery 2000 can be improved.

[0142] As shown in FIG. 4 , in a battery 2000, the negative electrode 200 may be the electrode 1000 according to the second embodiment. In this case, the negative electrode 200 includes the electrode layer 130 and the current collector 100 described in the second embodiment. Below, a battery 2000 in which the negative electrode 200 is the electrode 1000 according to the second embodiment will be described. However, the battery 2000 is not limited to the following form. In the battery 2000, the positive electrode 400 may be the electrode 1000 according to the second embodiment.

[0143] According to the above configuration, the cycle characteristics of the battery 2000 can be improved.

[0144] The electrolyte layer 300 is a layer containing an electrolyte material. Examples of the electrolyte material include a solid electrolyte. That is, the electrolyte layer 300 may be a solid electrolyte layer. The solid electrolytes exemplified as the solid electrolyte 13e may be used as the solid electrolyte contained in the electrolyte layer 300, and examples of the solid electrolyte that may be used include a sulfide solid electrolyte, an oxide solid electrolyte, a halide solid electrolyte, a polymer solid electrolyte, and a complex hydride solid electrolyte.

[0145] The electrolyte layer 300 may contain a solid electrolyte as a main component. The electrolyte layer 300 may contain 70% or more (70 mass % or more) of the solid electrolyte in terms of mass ratio relative to the entire electrolyte layer 300.

[0146] According to the above configuration, the charge and discharge characteristics of the battery 2000 can be improved.

[0147] The electrolyte layer 300 may contain a solid electrolyte as a main component. The electrolyte layer 300 may contain 70% or more (70 mass % or more) of the solid electrolyte in terms of mass ratio relative to the entire electrolyte layer 300.

[0148] According to the above configuration, the charge and discharge characteristics of the battery 2000 can be improved.

[0149] The electrolyte layer 300 contains a solid electrolyte as a main component, and may further contain unavoidable impurities, or starting materials, by-products, decomposition products, and the like used in synthesizing the solid electrolyte.

[0150] The electrolyte layer 300 may contain a solid electrolyte in a mass ratio of 100% (100 mass %) relative to the entire electrolyte layer 300, excluding unavoidable impurities.

[0151] According to the above configuration, the charge and discharge characteristics of the battery 2000 can be further improved.

[0152] The electrolyte layer 300 may include two or more of the materials listed as solid electrolytes. For example, the electrolyte layer 300 may include a halide solid electrolyte and a sulfide solid electrolyte.

[0153] The thickness of the electrolyte layer 300 may be 1 μm or more and 300 μm or less. When the thickness of the electrolyte layer 300 is 1 μm or more, the possibility of a short circuit between the negative electrode 200 and the positive electrode 400 decreases. When the thickness of the electrolyte layer 300 is 300 μm or less, the battery 2000 can easily operate at high power. In other words, if the thickness of the electrolyte layer 300 is appropriately adjusted, the safety of the battery 2000 can be sufficiently ensured and the battery 2000 can be operated at high power.

[0154] The shape of the solid electrolyte contained in the electrolyte layer 300 is not particularly limited. The shape of the solid electrolyte may be needle-like, spherical, oval-spherical, etc. The shape of the solid electrolyte may also be particulate.

[0155] The positive electrode 400 may contain an electrolyte material, for example, a solid electrolyte. The solid electrolytes exemplified as materials constituting the electrolyte layer 300 can be used as the solid electrolyte. With the above configuration, ion conductivity (e.g., lithium ion conductivity) within the positive electrode 400 is improved, and the battery 2000 can operate at high power.

[0156] The positive electrode 400 includes, for example, a material having the property of absorbing and releasing metal ions (for example, lithium ions) as a positive electrode active material. The materials exemplified in the first embodiment may also be used as the positive electrode active material.

[0157] The median diameter of the positive electrode active material may be 0.1 μm or more and 100 μm or less. When the median diameter of the positive electrode active material is 0.1 μm or more, the positive electrode active material and the solid electrolyte can be well dispersed in the positive electrode 400. This improves the charge / discharge characteristics of the battery 2000. When the median diameter of the positive electrode active material is 100 μm or less, the lithium diffusion rate within the positive electrode active material improves. This allows the battery 2000 to operate at high power.

[0158] The median diameter of the positive electrode active material may be larger than the median diameter of the solid electrolyte, which allows the solid electrolyte and the positive electrode active material to be dispersed well.

[0159] In the positive electrode 400, the volume ratio "v2:100-v2" of the positive electrode active material to the solid electrolyte may satisfy 30≦v2≦95. v2 indicates the volume ratio of the positive electrode active material when the total volume of the positive electrode active material and solid electrolyte contained in the positive electrode 400 is regarded as 100. When 30≦v2 is satisfied, it is easy to ensure sufficient energy density for the battery 2000. When v2≦95 is satisfied, it is easy for the battery 2000 to operate at high output.

[0160] The thickness of the positive electrode 400 may be 10 μm or more and 500 μm or less. When the thickness of the positive electrode 400 is 10 μm or more, sufficient energy density can be easily ensured for the battery 2000. When the thickness of the positive electrode 400 is 500 μm or less, high-power operation of the battery 2000 can be more easily achieved.

[0161] The positive electrode active material may be coated with a coating material to reduce the interfacial resistance with the solid electrolyte. A material with low electronic conductivity may be used as the coating material. An oxide material, an oxide solid electrolyte, or the like may be used as the coating material. The materials exemplified in the first embodiment may also be used as the coating material.

[0162] At least one selected from the group consisting of the electrolyte layer 300 and the positive electrode 400 may contain a binder to improve adhesion between particles. The materials exemplified in embodiment 1 may be used as the binder. One binder may be used alone, or two or more binders may be used in combination.

[0163] An elastomer may be used as the binder from the viewpoint of excellent binding properties. Elastomer refers to a polymer having elasticity. The elastomer used as the binder may be a thermoplastic elastomer or a thermosetting elastomer. The binder may contain a thermoplastic elastomer. The materials exemplified in embodiment 1 may be used as the elastomer. When the binder contains an elastomer, for example, high filling of the electrolyte layer 300 or the positive electrode 400 can be achieved by thermal compression during the production of the battery 2000.

[0164] At least one selected from the group consisting of the electrode layer 130 of the negative electrode 200, the electrolyte layer 300, and the positive electrode 400 may contain a nonaqueous electrolyte, a gel electrolyte, or an ionic liquid for the purpose of facilitating the exchange of lithium ions and improving the output characteristics of the battery 2000.

[0165] The nonaqueous electrolyte contains a nonaqueous solvent and a lithium salt dissolved in the nonaqueous solvent. Examples of nonaqueous solvents that can be used include cyclic carbonate ester solvents, chain carbonate ester solvents, cyclic ether solvents, chain ether solvents, cyclic ester solvents, chain ester solvents, and fluorine-containing solvents. Examples of cyclic carbonate ester solvents include ethylene carbonate, propylene carbonate, and butylene carbonate. Examples of chain carbonate ester solvents include dimethyl carbonate, ethyl methyl carbonate, and diethyl carbonate. Examples of cyclic ether solvents include tetrahydrofuran, 1,4-dioxane, and 1,3-dioxolane. Examples of chain ether solvents include 1,2-dimethoxyethane and 1,2-diethoxyethane. Examples of cyclic ester solvents include γ-butyrolactone. Examples of chain ester solvents include methyl acetate. Examples of fluorine-containing solvents include fluoroethylene carbonate, methyl fluoropropionate, fluorobenzene, fluoroethyl methyl carbonate, fluorodimethylene carbonate, etc. As the non-aqueous solvent, one non-aqueous solvent selected from these may be used alone, or a mixture of two or more non-aqueous solvents selected from these may be used.

[0166] The non-aqueous electrolyte may contain at least one fluorine solvent selected from the group consisting of fluoroethylene carbonate, methyl fluoropropionate, fluorobenzene, fluoroethyl methyl carbonate, and fluorodimethylene carbonate.

[0167] Examples of lithium salts include LiPF6, LiBF4, LiSbF6, LiAsF6, LiSO3CF3, LiN(SO2F)2, LiN(SO2CF3)2, LiN(SO2C2F5)2, LiN(SO2CF3)(SO2C4F9), and LiC(SO2CF3)3. As the lithium salt, one lithium salt selected from these may be used alone, or a mixture of two or more lithium salts selected from these may be used. The concentration of the lithium salt in the nonaqueous electrolyte may be 0.5 mol / L or more and 2 mol / L or less.

[0168] The gel electrolyte may be a polymer material containing a non-aqueous electrolyte, such as polyethylene oxide, polyacrylonitrile, polyvinylidene fluoride, polymethyl methacrylate, or a polymer having an ethylene oxide bond.

[0169] The cations constituting the ionic liquid may be aliphatic chain quaternary cations such as tetraalkylammonium and tetraalkylphosphonium, aliphatic cyclic ammoniums such as pyrrolidiniums, morpholiniums, imidazoliniums, tetrahydropyrimidiniums, piperaziniums, and piperidiniums, and nitrogen-containing heterocyclic aromatic cations such as pyridiniums and imidazoliums. The anions constituting the ionic liquid may be PF6 - , BF4 - , SbF6 - , AsF6 - , SO3CF3 - , N(SO2F)2 - , N(SO2CF3)2 - , N(SO2C2F5)2 - , N(SO2CF3)(SO2C4F9) - , C(SO2CF3)3 - The ionic liquid may contain a lithium salt.

[0170] At least one selected from the group consisting of the electrode layer 130 of the negative electrode 200 and the positive electrode 400 may contain a conductive additive for the purpose of improving electronic conductivity. As the conductive additive, the materials exemplified in embodiment 1 can be used.

[0171] At least one selected from the group consisting of the electrode layer 130 of the negative electrode 200 and the positive electrode 400 may contain a dispersant to improve the dispersibility of the solid electrolyte and the active material. The materials exemplified in embodiment 1 can be used as the dispersant.

[0172] The shape of the battery 2000 may be coin type, cylindrical type, square type, sheet type, button type, flat type, laminated type, or the like.

[0173] [Battery manufacturing method] The battery 2000 can be manufactured, for example, by the following method. First, the current collector 100, materials for forming the electrode layer 130, materials for forming the electrolyte layer 300, materials for forming the positive electrode 400, and a current collector for the positive electrode 400 are prepared. Using these, a laminate in which the negative electrode 200, the electrolyte layer 300, and the positive electrode 400 are arranged in this order is fabricated by a known method. In this way, the battery 2000 can be manufactured.

[0174] The battery 2000 may be manufactured by, for example, the following method. First, as described above, after manufacturing the electrode 1000, a solid electrolyte composition for forming the electrolyte layer 300 is applied to the electrode 1000 to form a coating film (second coating film). The solid electrolyte composition may contain a solid electrolyte. The solid electrolyte composition may further contain a solvent (second solvent). As the solid electrolyte composition, a dispersion liquid (slurry) in which a solid electrolyte and a binder are dispersed in a solvent may be used. As the solvent, a solvent that does not react with the solid electrolyte, such as an aromatic hydrocarbon solvent such as tetralin, may be used. The method used to form the coating film (first coating film) can be used as a method for applying the solid electrolyte composition. After forming the coating film, the solvent may be removed from the coating film. Specifically, the obtained coating film can be dried to remove the solvent from the coating film. In this way, the electrolyte layer 300 can be formed. Next, the negative electrode 200 and the positive electrode 400 are arranged so that the coating film (electrolyte layer 300) is sandwiched between them. In this way, the battery 2000 can be obtained.

[0175] After removing the solvent, the laminate of the electrode 1000 and the coating film may be subjected to a press treatment (second press treatment). Specifically, the press treatment is performed on a laminate of the electrolyte layer 300 obtained by drying the coating film, the negative electrode 200, and the positive electrode 400. By performing the press treatment on the laminate, filling of the material contained in the battery 2000 is promoted. For example, a roll press, a plate press, or an isostatic press (ISP) is used for the press treatment of the coating film. In the press treatment, a press machine is used to pressure-mold the laminate at a high temperature (for example, a temperature of 120°C or higher and 195°C or lower). The press treatment (second press treatment) can be performed at a higher pressure than the press treatment (first press treatment) used in manufacturing the electrode 1000. According to this method, the output of the battery 2000 can be increased.

[0176] Fig. 5 is a cross-sectional view of a battery 3000 according to Modification 1. The battery 3000 can be a stack of a plurality of batteries 2000. In the example of Fig. 5, the battery 3000 is a stack of a battery 2001 and a battery 2002. Specifically, the battery 3000 includes a battery 2001 on one surface (first surface) of a current collector 111, and a battery 2002 on the other surface (second surface) of the current collector 111.

[0177] The battery 3000 may be manufactured by the following method. First, a current collector 101 is prepared, in which coating layers 121 and 122 are arranged on both sides of a substrate 111. Next, a negative electrode (first negative electrode 201) having an electrode layer 131 laminated thereon, an electrolyte layer (first electrolyte layer 301), and a positive electrode (first positive electrode 401) are arranged in this order on a first surface of the current collector 101. A negative electrode (second negative electrode 202) having an electrode layer 132 laminated thereon, an electrolyte layer (second electrolyte layer 302), and a positive electrode (second positive electrode 402) are arranged in this order on a second surface of the current collector 101. This results in a laminate in which the first positive electrode 401, the first electrolyte layer 301, the first negative electrode 201 (electrode layer 131, coating layer 121, and current collector 101), the second negative electrode 202 (current collector 101, coating layer 122, and electrode layer 132), the second electrolyte layer 302, and the second positive electrode 402 are arranged in this order. Finally, the laminate is pressure-molded at high temperature (for example, a temperature of 120°C or higher and 195°C or lower) using a press, thereby producing a battery 3000. This method makes it possible to produce a laminate of two batteries 1001, 1002 while suppressing warping of the battery, and allows for more efficient production of a high-power battery 3000.

[0178] There is no particular limitation on the order in which the components are stacked in the production of the battery 3000. For example, after the first negative electrode 201 and the second negative electrode 202 are disposed on the current collector 101, the first electrolyte layer 301, the second electrolyte layer 302, the first positive electrode 401, and the second positive electrode 402 may be stacked in this order to produce a stack of two batteries 2001 and 2002.

[0179] FIG. 6 is a cross-sectional view of a battery 4000 according to Modification 2. The battery 4000 can be a stack of a plurality of batteries 2000. In the example of FIG. 6, the battery 3000 is a stack of batteries 2001 to 2006. Specifically, the battery 3000 is a stack obtained by further stacking batteries 2003 and 2005 in this order on the first surface side of the current collector 111 in the battery 3000 according to Modification 1, and further stacking batteries 2004 and 2006 in this order on the second surface side of the current collector 111.

[0180] The battery 4000 may be manufactured by preparing a plurality of batteries 2000 and counter electrode current collectors 410 according to the second embodiment, alternately stacking the batteries 2000 and the counter electrode current collectors 410, and bonding them together. An adhesive layer may be provided on the counter electrode current collector 410 to bond the batteries 2000 and the counter electrode current collector 410 together. The current collector 100 and the counter electrode current collector 231 may be provided with protrusions 11a and 41a protruding from the side surfaces of the battery 4000, respectively, and joined by welding or the like. The protrusion directions of the protrusions 11a of the current collector 100 and the protrusions 41a of the counter electrode current collector 410 are not particularly limited. In the example of FIG. 6, the protrusions 11a of the current collector 100 and the protrusions 41a of the counter electrode current collector 410 protrude in opposite directions from the side surfaces of the battery 4000, but they may also protrude in the same direction. In the example of FIG. 6, six batteries 2000 are stacked, but the number may be two to five, or seven or more.

[0181] (Other embodiments) (Addendum) The above description of the embodiments discloses the following techniques.

[0182] (Technology 1) A substrate; a coating layer that coats the substrate; Equipped with the surface on the coating layer side has a stripe shape composed of concave and convex portions on the surface, the linear density of the protrusions is greater than 2.5 / mm in at least a partial region of the surface on the coating layer side; Current collector.

[0183] According to the present disclosure, it is possible to provide a current collector suitable for improving the peel strength from an electrode layer.

[0184] (Technology 2) The current collector according to Technical Example 1, wherein the linear density of the protrusions is 6.8 / mm or less. With this configuration, a suitable current collector can be provided by improving the peel strength from the electrode layer.

[0185] (Technology 3) The current collector according to Technology 1 or 2, wherein in the region, the gloss of the surface on the coating layer side at an incident angle of 60 degrees is from 19 to 60. With this configuration, a suitable current collector can be provided by improving the peel strength from the electrode layer.

[0186] (Technology 4) A substrate; a coating layer that coats the substrate; Equipped with In at least a part of the surface on the coating layer side, the gloss of the surface on the coating layer side at an incident angle of 60 degrees is 19 or more and 60 or less. Current collector.

[0187] According to the present disclosure, it is possible to provide a current collector suitable for improving the peel strength from an electrode layer.

[0188] (Technology 5) The current collector according to any one of techniques 1 to 4, wherein in the region, the surface on the coating layer side has a maximum height roughness Rz of 1.0 μm or more. With this configuration, when an electrode composed of this current collector and the electrode layer is subjected to a press treatment, the peel strength between the electrode layer and the current collector can be further improved.

[0189] (Technology 6) The current collector according to any one of techniques 1 to 5, wherein the coating layer contains conductive carbon and a first binder. With this configuration, it is possible to provide a current collector suitable for improving the peel strength from the electrode layer, and to improve the output characteristics of an electrochemical device using this current collector.

[0190] (Technology 7) The current collector according to claim 6, wherein the first binder comprises at least one selected from the group consisting of polyimide, polyethersulfone, and polyvinylidene fluoride. These materials tend to exhibit high heat resistance. Therefore, this configuration enhances the effect of suppressing adhesion of the coating layer to production equipment, thereby improving the productivity of electrochemical devices.

[0191] (Technology 8) The current collector according to any one of techniques 1 to 7, wherein the substrate contains aluminum or an aluminum alloy. With this configuration, it is possible to provide a current collector suitable for improving the peel strength with respect to the electrode layer, and to improve the mass energy density of an electrochemical device using this current collector.

[0192] (Technology 9) An electrode comprising: the current collector according to any one of techniques 1 to 8; and an electrode layer disposed on the current collector. According to the present disclosure, an electrode having improved peel strength between the electrode layer and the current collector can be provided.

[0193] (Technology 10) The electrode according to Technology 9, wherein the electrode layer contains a solid electrolyte. According to this configuration, an electrode suitable for an electrochemical device, in particular a battery, in which the electrode layer contains a solid electrolyte can be provided.

[0194] (Technology 11) The electrode according to any one of claims 9 to 10, wherein the electrode layer includes a second binder, and the second binder includes a styrene-based elastomer. The styrene-based elastomer has excellent flexibility and elasticity, making it suitable as a binder for the electrode layer. Furthermore, this configuration can further improve the peel strength between the electrode layer and the current collector.

[0195] (Technology 12) The electrode according to Technical Problem 11, wherein the styrene-based elastomer includes at least one selected from the group consisting of modified SBR and modified SEBS. With this configuration, the peel strength between the electrode layer and the current collector can be further improved.

[0196] (Technology 13) A battery comprising a positive electrode, a negative electrode, and an electrolyte layer located between the positive electrode and the negative electrode, wherein at least one selected from the group consisting of the positive electrode and the negative electrode includes the electrode according to any one of techniques 9 to 12. According to the present disclosure, a battery suitable for improving output characteristics can be provided.

[0197] (Technology 14) A method for manufacturing an electrode, comprising forming a first coating film by applying an electrode composition to a current collector according to any one of techniques 1 to 8. According to the present disclosure, an electrode having improved peel strength between the electrode layer and the current collector can be obtained.

[0198] (Technology 15) The method for producing an electrode according to technique 14, wherein the electrode composition contains a first solvent, and further comprises removing the first solvent from the first coating film. According to such a method, by using an electrode composition containing a first solvent, the electrode composition becomes a slurry, which makes it easier to apply the electrode composition.

[0199] (Technology 16) The method for manufacturing an electrode according to technique 15 further includes performing a first press treatment on the first coating film after removing the first solvent. According to this method, the first press treatment promotes filling of the material of the electrode layer. Also, the peel strength between the electrode layer and the current collector can be further improved.

[0200] (Technology 17) A method for manufacturing a battery, comprising forming a second coating film by applying a solid electrolyte composition to an electrode manufactured by the method according to any one of techniques 14 to 16. The present disclosure can provide a battery suitable for improving output characteristics.

[0201] (Technology 18) The battery manufacturing method according to Technical 17, wherein the solid electrolyte composition contains a second solvent, and the manufacturing method further includes removing the second solvent from the second coating film and performing a second press treatment on the second coating film. According to this method, by using a solid electrolyte composition containing a second solvent, the solid electrolyte composition becomes a slurry, which makes it easier to apply the solid electrolyte composition. In addition, the second press treatment makes it possible to suppress warping of the battery, allowing for more efficient battery manufacturing. [Example]

[0202] Hereinafter, the present disclosure will be described in detail using examples and comparative examples. Note that the current collector, electrode, and battery of the present disclosure are not limited to the following examples.

[0203] [Preparation of current collector] <Example 1-1> Conductive carbon, a first binder, and a solvent were kneaded to prepare a coating material with a solid content of 15% by mass. Graphite (Gr: Nippon Graphite Industries Co., Ltd., UP-based graphite) and carbon black (CB: Denka Corporation) were used as the conductive carbon. A soluble polyimide (PI) with a glass transition temperature (Tg) of 236°C was used as the first binder. N-methyl-2-pyrrolidone (NMP) was used as the solvent. Next, the coating material was applied in the MD direction to one side (first side) of a substrate using a gravure coater with a stripe-shaped plate to form a coating film. Aluminum alloy foil (A3003 foil, thickness: 15 μm) was used as the substrate. The coating film was dried at 165°C to form a coating layer on the first side. The coating material was then applied to the other side (second side) of the substrate to form a coating film. The coating film was dried at 165°C to form a coating layer on the second side. In this way, a current collector having coating layers on both sides was obtained. In the current collector of Example 1-1, the mass per unit area (basis weight) of the coating layer on the first surface side was 1.25 g / m 2 The mass per unit area (basis weight) of the coating layer on the second surface side was 1.29 g / m 2 It was.

[0204] <Example 1-2> As the first binder, polyvinylidene fluoride (PVDF) was used instead of the first binder of Example 1-1. As the conductive carbon, in addition to the conductive carbon of Example 1-1, vapor-grown carbon fiber (VGCF-H (registered trademark) manufactured by Resonac Co., Ltd.) was further used. Except for the above changes, a coating material was prepared using the same raw materials and solid content ratio as in Example 1-1. Using the obtained coating material, a current collector of Example 1-2 was prepared by the same method as in Example 1-1. In the current collector of Example 1-2, the mass per unit area (basis weight) of the coating layer on the first surface side was 0.90 g / m 2The mass per unit area (basis weight) of the coating layer on the second surface side was 0.91 g / m 2 It was.

[0205] <Comparative Example 1-1> As the conductive carbon, in addition to the conductive carbon of Example 1-1, crushed carbon fiber (CF: Mitsubishi Chemical Corporation, K223HM) was further used. Except for the above changes, a coating material was prepared using the same raw materials and solid content ratio as in Example 1-1. Using the obtained coating material, a current collector of Comparative Example 1-1 was prepared by the same method as in Example 1-1. In the current collector of Comparative Example 1-1, the mass per unit area (basis weight) of the coating layer on the first surface side was 1.87 g / m 2 The mass per unit area (basis weight) of the coating layer on the second surface side was 1.87 g / m 2 It was.

[0206] <Comparative Example 1-2> As the conductive carbon, pulverized carbon fiber (CF: Mitsubishi Chemical Corporation, K223HM) was used instead of the conductive carbon of Example 1-1. Except for the above changes, a coating material was prepared using the same raw materials and solid content ratio as in Example 1-1. Using the obtained coating material, a current collector of Comparative Example 1-2 was prepared by the same method as in Example 1-1. In the current collector of Comparative Example 1-2, the mass per unit area (basis weight) of the coating layer on the first surface side was 1.89 g / m 2 The mass per unit area (basis weight) of the coating layer on the second surface side was 1.89 g / m 2 It was.

[0207] <Comparative Example 1-3> A current collector of Comparative Example 1-3 was produced using the same paint and method as in Example 1-1, except that a lattice-shaped plate was used. In the current collector of Comparative Example 1-3, the mass per unit area (basis weight) of the coating layer on the first surface side was 0.57 g / m 2 The mass per unit area (basis weight) of the coating layer on the second surface side was 0.58 g / m 2 It was.

[0208] <Comparative Example 1-4> As the first binder, polyethersulfone (PES) was used instead of the first binder of Example 1-1. Except for the above changes, a coating material was prepared using the same raw materials and solid content ratio as in Example 1-1. Using the obtained coating material, a current collector of Comparative Example 1-4 was prepared by the same method as in Example 1-1. In the current collector of Comparative Example 1-4, the mass per unit area (basis weight) of the coating layer on the first surface side was 1.33 g / m 2 The mass per unit area (weight) of the coating layer on the second surface side was 1.35 g / m 2 It was.

[0209] <Comparative Example 1-5> As the first binder, polyvinylidene fluoride (PVDF) was used instead of the first binder of Example 1-1. Except for the above changes, a coating material was prepared using the same raw materials and solid content ratio as in Example 1-1. Using the obtained coating material, a current collector of Comparative Example 1-5 was prepared by the same method as in Example 1-1. In the current collector of Comparative Example 1-5, the mass per unit area (basis weight) of the coating layer on the first surface side was 0.93 g / m 2 The mass per unit area (basis weight) of the coating layer on the second surface side was 0.95 g / m 2 It was.

[0210] [Observation of surface shape] For the current collectors of Example 1-1, Example 1-2, and Comparative Examples 1-1 to 1-5, backscattered electron composition images of the first surface of each current collector were obtained using the method described above, and the surface morphology was observed. A tabletop scanning electron microscope (JEOL, JCM-7000) was used to observe the surface morphology. The backscattered electron composition images were obtained at a magnification of 50x and an acceleration voltage of 15 kV. In the obtained backscattered electron composition images, a 3.25 mm reference line was drawn so as to maximize the number of intersections with dark areas representing stripe-shaped convex portions. The number of dark areas intersecting the line segment was then counted, and the linear density (lines / mm) of the convex portions was calculated by dividing this number by 3.25 mm. The backscattered electron composition images of the first surface of each current collector of Example 1-1, Example 1-2, and Comparative Examples 1-1 to 1-5 are shown in Figures 7A to 7B and Figures 8A to 8E, respectively, and the calculated linear density of the convex portions is shown in Table 1.

[0211] [Gloss measurement] The glossiness of the first surface of each of the current collectors of Example 1-1, Example 1-2, and Comparative Examples 1-1 to 1-5 was measured by the method described above. A gloss meter (PG-1M, manufactured by Nippon Denshoku Industries Co., Ltd.) was used to measure the glossiness. The glossiness was measured in both the MD and TD directions of the first surface of the current collector. The measurement results of the glossiness of the first surface of each of the current collectors of Example 1-1, Example 1-2, and Comparative Examples 1-1 to 1-5 are shown in Table 1.

[0212] [Measurement of arithmetic mean roughness and maximum height roughness] The arithmetic mean roughness and maximum height roughness were measured for each of the first surfaces of the current collectors of Example 1-1, Example 1-2, and Comparative Examples 1-1 to 1-5 using the methods described above. A stylus-type profilometer (P10, manufactured by KLT-Tencor) was used to measure the arithmetic mean roughness and maximum height roughness. Measurements were performed three times in each of the MD and TD directions of the first surface of the current collector, and the arithmetic mean roughness and maximum height roughness were obtained from the average values ​​of these measurements. The measurement results for the arithmetic mean roughness and maximum height roughness for the first surfaces of the current collectors of Example 1-1, Example 1-2, and Comparative Examples 1-1 to 1-5 are shown in Table 1.

[0213] [Electrode preparation] The electrodes of Example 1-1, Example 1-2, and Comparative Examples 1-1 to 1-5 were fabricated by forming an electrode layer on the first surface of each current collector by the following method. First, Li4Ti5O 12A mixed solution was prepared by weighing 250 g of Lithium Ion Oxide (LTO) and adding 136 g of tetralin and 15.0 g of a dispersant solution containing a dispersant at a concentration of 5% by mass. The dispersant used was 1-hydroxyethyl-2-alkenylimidazoline (BYK, DISPERBYK-109). Tetralin was used as the solvent for the dispersant solution. Next, this mixed solution was dispersed and kneaded using a benchtop digital ultrasonic homogenizer (BRANSON, SONIFIER SFX550). Then, 43.4 g of a second binder solution containing a second binder at a concentration of 5% by mass, 2.75 g of vapor-grown carbon fiber (Resonac, VGCF-H (registered trademark)), and 84.0 g of LiI-LiBr-Li2S-P2S5-based glass ceramics (LPS) were added to the mixed solution, dispersed, and kneaded to prepare an electrode composition (slurry). The second binder used was a mixture containing a hydrogenated styrene-based thermoplastic elastomer (modified SEBS, manufactured by Asahi Kasei Corporation, Tuftec (registered trademark) MP10) and a hydrogenated block copolymer (SEBS, manufactured by Kraton Corporation, G1633) in a mass ratio of 1:1. Tetralin was used as the solvent for the second binder solution. Finally, the electrode composition was applied to the first surface of the current collector using an applicator, and the resulting coating was dried at 100°C for 1 hour in a vacuum atmosphere to obtain electrodes for Example 1-1, Example 1-2, and Comparative Examples 1-1 to 1-5.

[0214] [Peel strength measurement] The peel strength between the electrode layer and the current collector was measured on the first side of the current collector using a universal testing machine (A&D Co., Ltd., RTH-1310) in a dry room with a dew point of -50°C or less. First, a 15 mm-wide electrode was attached to a test plate with double-sided tape. Specifically, the electrode layer of the electrode was attached to the test plate via the double-sided tape. Next, using a tester equipped with a jig for 90° adhesive tape peel tests, the electrode layer was peeled from the current collector in the TD direction at a peel angle of 90° and a peel rate of 5 mm / min. After the start of the measurement, the measurements from the first 5 mm to 12 mm peeled from the current collector were not used. Subsequently, measurements (unit: N) were continuously recorded for the 5 mm length of the electrode layer peeled from the current collector. The average value (Av) of these measurements divided by the width of the electrode was considered to be the peel strength (unit: N / m) between the electrode layer and the current collector of the electrode. Table 1 shows the measurement results of the peel strength between the electrode layer and the current collector in the electrodes of Example 1-1, Example 1-2, and Comparative Examples 1-1 to 1-5.

[0215] [Table 1]

[0216] 7A and 7B, the first surfaces of the current collectors of Examples 1-1 and 1-2 had a striped shape, and the linear density of the striped protrusions was greater than 2.5 lines / mm, as shown in Table 1. The electrodes of Examples 1-1 and 1-2, in which the linear density of the striped protrusions was within the above range, exhibited a high peel strength of 0.40 N / m or more between the electrode layer and the current collector, compared to the electrodes of Comparative Examples 1-1 to 1-5.

[0217] 9A is a graph showing the relationship between the gloss along the MD of the first surface of the current collector and the peel strength between the electrode layer and the current collector at an incident angle of 60 degrees for the electrodes of Example 1-1, Example 1-2, and Comparative Examples 1-1 to 1-5. FIG. 9B is a graph showing the relationship between the gloss along the TD of the first surface of the current collector and the peel strength between the electrode layer and the current collector at an incident angle of 60 degrees for the electrodes of Example 1-1, Example 1-2, and Comparative Examples 1-1 to 1-5. From the approximation curves based on the plots in FIGS. 9A and 9B , it is estimated that when the gloss of the first surface of the current collector at an incident angle of 60 degrees is 19 or more and 60 or less, the peel strength between the electrode layer and the current collector will be as high as 0.40 N / m or more.

[0218] <Example 2-1> [Preparation of current collector] Conductive carbon, a first binder, and a solvent were kneaded to prepare a coating material with a solid content of 15% by mass. Graphite (Gr: Nippon Graphite Industries Co., Ltd., UP-based graphite) and carbon black (CB: Denka Corporation) were used as the conductive carbon. A soluble polyimide (PI) with a glass transition temperature (Tg) of 236°C was used as the first binder. N-methyl-2-pyrrolidone (NMP) was used as the solvent. Next, a coating film was formed by applying the coating material to one side (first side) of the substrate using a gravure coater equipped with a stripe-shaped plate, and moving the substrate relative to the gravure coater in the MD direction. Aluminum alloy foil (A3003 foil, thickness: 15 μm) was used as the substrate. The coating film was dried at 165°C to form a coating layer on the first side of the substrate. The coating material was then applied to the other side (second side) of the substrate to form a coating film. The coating film was dried at 165°C to form a coating layer on the second surface of the substrate. This resulted in a current collector of Example 2-1 having coating layers on both surfaces. In the current collector of Example 2-1, the mass per unit area (basis weight) of the coating layer on the first surface side was 1.28 g / m 2 The mass per unit area (basis weight) of the coating layer on the second surface side was 1.26 g / m 2 It was.

[0219] <Example 2-2> The current collector of Example 2-2 was produced using the same paint and method as in Example 2-1, except that after drying the coating layers on both sides, heat treatment was performed at 200°C under vacuum. In the current collector of Example 2-2, the mass per unit area (basis weight) of the coating layer on the first surface side was 1.34 g / m 2 The mass per unit area (basis weight) of the coating layer on the second surface side was 1.32 g / m 2 It was.

[0220] <Example 2-3> As the first binder, a soluble polyimide (PI) with a glass transition temperature (Tg) of 195°C was used instead of the first binder of Example 2-1. As the solvent, cyclohexanone was used instead of the solvent of Example 2-1. Except for the above changes, a coating material was prepared using the same raw materials and solid content ratio as in Example 2-1. Using the obtained coating material, a current collector of Example 2-3 was prepared by the same method as in Example 2-1. In the current collector of Example 2-3, the mass per unit area (basis weight) of the coating layer on the first surface side was 1.22 g / m 2 The mass per unit area (basis weight) of the coating layer on the second surface side was 1.23 g / m 2 It was.

[0221] <Comparative Example 2-1> A coating material was prepared using the same raw materials and solid content ratio as in Example 2-1, except that only carbon black (CB) was used as the conductive carbon. Using the resulting coating material, a current collector of Comparative Example 2-1 was prepared by the same method as in Example 2-1. In the current collector of Comparative Example 2-1, the mass per unit area (basis weight) of the coating layer on the first surface side was 1.10 g / m 2 The mass per unit area (basis weight) of the coating layer on the second surface side was 1.15 g / m 2 It was.

[0222] [Current collector evaluation] The surface morphology of the current collectors of Examples 2-1 to 2-3 and Comparative Example 2-1 was observed, and the gloss and surface roughness were measured using the methods described above. Backscattered electron composition images of the first surfaces of the current collectors of Examples 2-1 to 2-3 and Comparative Example 2-1 are shown in Figures 10A to 10C and Figure 11, respectively. The calculated linear density of the protrusions on the coating layer side of the first surfaces of the current collectors of Examples 2-1 to 2-3 and Comparative Example 2-1, as well as the measured gloss and surface roughness, are shown in Table 2.

[0223] [Preparation of electrode composition] In order to form an electrode layer on the current collector of Example 2-1 and Comparative Example 2-1, an electrode composition was prepared by the following method. First, LTO (density: 3.54 g / cm) was dissolved in an argon glove box with a dew point of −60° C. or less. 3 A mixture of LTO, a dispersant solution containing 5% by mass of dispersant, and a solvent was prepared so that the mass ratio of LTO to dispersant was 100:0.3. 1-Hydroxyethyl-2-alkenylimidazoline (BYK, DISPERBYK-109, density: 0.939 g / cm) was used as the dispersant. 3 ) was used. Tetralin was used as the solvent for the dispersant solution. Next, this mixture was dispersed and kneaded using a tabletop digital ultrasonic homogenizer (SONIFIER SFX550, manufactured by BRANSON). After that, LTO, a second binder, and VGCF-H (density: 2.00 g / cm 3 ), and LPS (2.21 g / cm 3 A second binder solution containing the second binder at a concentration of 5% by mass, VGCF-H, LPS, and a solvent were weighed out so that the mass ratio of LTO:second binder:VGCF-H:LPS was 100:0.867:1.10:33.6. The mixture was added to the mixture, dispersed, and kneaded to prepare an electrode composition (slurry). Solution-polymerized styrene-butadiene rubber (modified SBR: manufactured by Asahi Kasei Corporation, Asaprene® Y031, density: 0.94 g / cm) was used as the second binder. 3 Tetralin (manufactured by Kanto Chemical Co., Ltd.) was used as the solvent for the second binder solution.

[0224] In addition, a hydroxyl group-containing carboxylic acid ester (manufactured by BYK, DISPERBYK-108, density: 0.940 g / cm) was used as a dispersant for the electrode composition. 3 The electrode compositions of Example 2-2 and Comparative Example 2-3 were prepared in the same manner as the electrode compositions of Example 2-1 and Comparative Example 2-1, except that ) was used.

[0225] [Electrode preparation] Using a die coater installed in an environment with a dew point of -60°C or less, the electrode composition was applied to the first and second surfaces of the current collectors of Examples 2-1 to 2-3 and Comparative Example 2-1 to form coating films. The coating films were dried using hot air drying at a temperature of 80°C to 110°C to form an electrode layer on the first surface. The electrode composition was then applied to the other surface of the current collector to form a coating film. The coating film was dried using hot air drying at a temperature of 80°C to 110°C to form an electrode layer on the second surface. In this way, electrodes having electrode layers on both surfaces were obtained for Examples 2-1 to 2-3 and Comparative Example 2-1. Three electrodes were produced for each of Examples 2-1 to 2-3, and six electrodes were produced for Comparative Example 2-1.

[0226] Of the three electrodes obtained in Example 2-1, one electrode was not subjected to a press treatment, and two electrodes were subjected to different press treatments (see the three plots of Example 2-1 in FIG. 12 ). As a result, three electrodes of Example 2-1 with different electrode layer densities were obtained. A roll press was used for the press treatment. As with Example 2-1, for the three electrodes obtained in Example 2-2, one electrode was not subjected to a press treatment, and two electrodes were subjected to different press treatments (see the three plots of Example 2-2 in FIG. 12 ). As a result, three electrodes of Example 2-2 with different electrode layer densities were obtained. As with Example 2-1, for the three electrodes obtained in Example 2-3, one electrode was not subjected to a press treatment, and two electrodes were subjected to different press treatments (see the three plots of Example 2-3 in FIG. 12 ). As a result, three electrodes of Example 2-3 with different electrode layer densities were obtained. Of the six electrodes obtained in Comparative Example 2-1, one electrode was not subjected to a press treatment, and five electrodes were subjected to different press treatments (see the six plots for Comparative Example 2-1 in FIG. 12). As a result, six electrodes of Comparative Example 2-1 with different electrode layer densities were obtained. Three electrodes of Example 2-1, three electrodes of Example 2-2, three electrodes of Example 2-3, and six electrodes of Comparative Example 2-1 were each punched out into 20 mm squares, and the weight and thickness of the electrode layer on one side of each was measured, and the electrode layer density under each press condition was calculated.

[0227] [Peel strength measurement] The peel strength between the electrode layer on the first surface side and the current collector was measured by the above-described method for each of the three electrodes of Example 2-1, the three electrodes of Example 2-2, the three electrodes of Example 2-3, and the six electrodes of Comparative Example 2-1. The relationship between the peel strength and the electrode layer density for the electrodes of Examples 2-1 to 2-3 and Comparative Example 2-1 is shown in Figure 12.

[0228] [Table 2]

[0229] As shown in Table 2, the first surfaces of the current collectors of Examples 2-1 to 2-3 had a striped pattern, and the linear density of the striped projections was greater than 2.5 lines / mm. FIG. 12 is a graph showing the relationship between peel strength and electrode layer density. As shown in FIG. 12, the current collectors of Examples 2-1 to 2-3, in which the linear density of the striped projections was within the above range, exhibited high values ​​of peel strength between the electrode layer and the current collector. Furthermore, in the current collectors of Examples 2-1 to 2-3, the peel strength between the electrode layer and the current collector showed a high rate of increase as the electrode layer density increased due to the press treatment.

[0230] As shown in Table 2, the gloss of the first surface of the current collectors of Examples 2-1 to 2-3 was 19 or more and 60 or less, similar to Examples 1-1 and 1-2. As shown in Fig. 12, the current collectors of Examples 2-1 to 2-3 having a gloss within such a range exhibited high peel strength between the electrode layer and the current collector. [Industrial Applicability]

[0231] The current collector of the present disclosure can be used in electrochemical devices such as batteries and capacitors. [Explanation of symbols]

[0232] 100 Current Collector 110, 111 board 11a Projection 120, 121, 122 Covering layer 12b First Binder 12c Conductive Carbon 12s recess 12t convex part 130, 131, 132 electrode layer 13a Active material 13b Second binder 13e solid electrolyte 200, 201, 202 negative electrode 300, 301, 302 electrolyte layer 400, 401, 402 positive electrode 410 Counter electrode current collector 41a Protrusion 1000 electrodes 2000, 2001, 2002, 2003, 2004, 2005, 2006, 3000, 4000 batteries

Claims

1. A substrate; a coating layer that coats the substrate; Equipped with the surface on the coating layer side has a stripe shape composed of concave and convex portions on the surface, the linear density of the protrusions is greater than 2.5 / mm in at least a part of the surface on the coating layer side; Current collector.

2. The linear density of the protrusions is 6.8 lines / mm or less. The current collector according to claim 1 .

3. In the region, the gloss of the surface on the coating layer side at an incident angle of 60 degrees is 19 or more and 60 or less. The current collector according to claim 1 .

4. A substrate; a coating layer that coats the substrate; Equipped with In at least a part of the surface on the coating layer side, the gloss of the surface on the coating layer side at an incident angle of 60 degrees is 19 or more and 60 or less. Current collector.

5. In the region, the surface roughness in maximum height Rz on the coating layer side is 1.0 μm or more. The current collector according to claim 1 .

6. the coating layer contains conductive carbon and a first binder; The current collector according to claim 1 .

7. the first binder includes at least one selected from the group consisting of polyimide, polyethersulfone, and polyvinylidene fluoride; The current collector according to claim 6 .

8. the substrate comprises aluminum or an aluminum alloy; The current collector according to claim 1 .

9. The current collector according to any one of claims 1 to 4; an electrode layer disposed on the current collector; An electrode comprising:

10. The electrode layer includes a solid electrolyte.

10. The electrode of claim 9.

11. the electrode layer includes a second binder; The second binder includes a styrene-based elastomer.

10. The electrode of claim 9.

12. The styrene-based elastomer includes at least one selected from the group consisting of modified SBR and modified SEBS.

12. The electrode of claim 11.

13. A positive electrode and a negative electrode; an electrolyte layer located between the positive electrode and the negative electrode; Equipped with At least one selected from the group consisting of the positive electrode and the negative electrode includes the electrode according to claim 9. battery.

14. The method comprises applying an electrode composition to the current collector according to claim 1 to form a first coating film. Electrode manufacturing method.

15. the electrode composition includes a first solvent; further comprising removing the first solvent from the first coating film. The method for manufacturing the electrode according to claim 14.

16. The method further includes performing a first press treatment on the first coating film after removing the first solvent. A method for producing the electrode according to claim 15.

17. and applying a solid electrolyte composition to the electrode produced by the method according to claim 14 to form a second coating film. How batteries are manufactured.

18. the solid electrolyte composition includes a second solvent, The manufacturing method includes: removing the second solvent from the second coating; performing a second press treatment on the second coating film; The method of claim 17 further comprising:

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