JP2013030410A - Collector, electrode structure, nonaqueous electrolyte battery, and capacitor component - Google Patents

Abstract

[PROBLEMS] To reduce the internal resistance of a non-aqueous electrolyte battery, and can be suitably used for a non-aqueous electrolyte battery such as a lithium ion secondary battery, a power storage component such as an electric double layer capacitor or a lithium ion capacitor, and has a high rate characteristic. A current collector that can be improved is provided.
A current collector in which a conductive layer having a conductive concavo-convex shape is formed on at least one surface of a conductive substrate, an electrode structure including the current collector, a non-aqueous electrolyte battery, and an electricity Double layer capacitor or lithium ion capacitor.
[Selection] Figure 2

Description

  The present invention relates to a current collector, an electrode structure, a nonaqueous electrolyte battery, and a power storage component (such as an electric double layer capacitor and a lithium ion capacitor) suitable for charging and discharging at a large current density.

  Conventionally, a non-aqueous electrolyte battery represented by a lithium ion battery has been required to be shortened in charging time. For this purpose, it is necessary to be able to be charged with a large current density. In addition, in order to obtain sufficient acceleration performance for non-aqueous electrolyte batteries for automobiles, it is required that high output discharge with a large current density can be performed. Thus, in order to improve the characteristic (high rate characteristic) in which the battery capacity does not decrease even when charging / discharging at a large current density, it is important to reduce the internal resistance of the battery. The same can be said for the electric double layer / lithium ion capacitor.

  The internal resistance includes the electrical resistance of the constituent material, the interfacial resistance between the constituent elements, the conduction resistance of ions that are charged particles in the electrolytic solution, the electrode reaction resistance, and the like, and each needs to be reduced. One of the important internal resistances is the interfacial resistance generated between the current collector made of metal foil such as aluminum foil and copper foil and the active material layer. One of the methods for reducing this interfacial resistance is this interface resistance. It is effective to improve the adhesion.

  As a method for improving the adhesion between the current collector and the active material layer, it has been conventionally proposed to coat the current collector with a conductive resin and apply the active material layer thereon. Patent Document 1 discloses a technique for forming a conductive coating film by applying a conductive paint containing a conductive filler, vinyl butyral as a binder, and dibutyl phthalate as a plasticizer to a positive electrode current collector. Patent Document 2 discloses a technique for forming a conductive coating film containing polyacrylic acid or a copolymer of acrylic acid and an acrylate ester as a main binder and carbon powder as a conductive filler on a positive electrode current collector. It is disclosed.

JP-A-2-109256 Japanese Patent Laid-Open No. 62-160656

As described above, various methods for improving the adhesion between the current collector and the active material layer have been conventionally studied. However, it is desired to further improve the adhesion.
The object of the present invention is to reduce the internal resistance of the nonaqueous electrolyte battery, and can be suitably used for nonaqueous electrolyte batteries such as lithium ion secondary batteries, electric double layer capacitors and lithium ion capacitors and other power storage components, An object of the present invention is to provide a current collector capable of improving high rate characteristics. The current collector of the present invention can provide an electrode structure having a low interface resistance with the active material layer or the electrode material layer by forming the active material layer or the electrode material layer. In addition, a nonaqueous electrolyte battery using an electrode structure in which an active material layer is formed on a current collector of the present invention is a non-aqueous electrolyte battery that has a current collector having the above characteristics and has reduced internal resistance and improved high rate characteristics. A water electrolyte battery can be provided. Furthermore, the present invention provides a power storage component such as an electric double layer capacitor or a lithium ion capacitor that is required for charging and discharging with a large current used in a copying machine or an automobile.

  As a result of intensive studies in view of the above circumstances, the present inventor has obtained a non-aqueous electrolyte battery and a power storage component that are excellent in improving high rate characteristics and improving electrode life by using a current collector as described below. It has been found and the present invention has been made.

That is, according to the present invention, a current collector in which a conductive resin layer is formed on at least one surface of a conductive substrate, and the surface of the resin layer has a concavo-convex shape, and this An electrode structure including a current collector, a nonaqueous electrolyte battery, and a power storage component (eg, an electric double layer capacitor or a lithium ion capacitor) are provided.

  According to the present invention, since the surface of the resin layer is uneven, when an active material layer or an electrode material layer (hereinafter referred to as “active material layer or the like”) is formed on the resin layer, Since the contact area with the active material layer or the like increases and the active material layer or the like bites into the resin layer, the adhesion between the resin layer and the active material layer or the like is improved. Therefore, by using the current collector of the present invention, it is possible to improve the high-rate characteristics and the life of non-aqueous electrolyte batteries and power storage components.

  The current collector of the present invention is suitable for charging / discharging at a large current density and can have a long life. An electrode structure comprising the current collector of the present invention, a non-aqueous electrolyte battery such as a lithium ion battery, The electric double layer capacitor, the lithium ion capacitor, and the power storage component are excellent in charge / discharge characteristics at a large current density and have a long life. Furthermore, according to the current collector of the present invention, since the uneven shape on the surface of the resin layer is controlled, it can be used as a current collector having various variations, and an electrode structure using the current collector, a non-aqueous electrolyte It is possible to flexibly cope with the adjustment of the amount of the active material layer, etc., by changing the unevenness count according to the use and properties of the battery.

It is sectional drawing which shows the structure of the electrical power collector of one Embodiment of this invention. It is sectional drawing which shows the structure of the electrode structure formed using the electrical power collector of one Embodiment of this invention. It is sectional drawing for demonstrating the formation method of the resin layer of the electrical power collector of one Embodiment of this invention. It is sectional drawing for demonstrating another formation method of the resin layer of the electrical power collector of one Embodiment of this invention. It is a top view which shows the grid | lattice (90 degree | times) uneven | corrugated shape of the resin layer of the electrical power collector of one Embodiment of this invention. It is a top view which shows the grid | lattice (45 degree | times) uneven | corrugated shape of the resin layer of the electrical power collector of one Embodiment of this invention. It is a top view which shows the honeycomb-shaped uneven | corrugated shape of the resin layer of the electrical power collector of one Embodiment of this invention. It is a top view which shows the dot-shaped uneven | corrugated shape of the resin layer of the electrical power collector of one Embodiment of this invention. It is a top view which shows the dot-shaped uneven | corrugated shape of another form of the resin layer of the electrical power collector of one Embodiment of this invention.

Hereinafter, the current collector of one embodiment of the present invention will be described with reference to FIG.
As shown in FIG. 1, the current collector 1 of the present invention is a current collector 1 in which a conductive resin layer (current collector resin layer) 5 is formed on at least one surface of a conductive substrate 3. The resin layer 5 has an uneven shape 6. Further, as shown in FIG. 2, by forming an active material layer 9 or the like on the resin layer 5 of the current collector 1, it is suitable for a non-aqueous electrolyte battery, an electric double layer capacitor, or a lithium ion capacitor. The electrode structure 7 can be formed.
Hereinafter, each component will be described in detail.

(1) Conductive base material As the conductive base material of the present invention, various metal foils can be used. As the metal foil, aluminum foil, aluminum alloy foil, copper foil, stainless steel foil, nickel foil or the like can be used for the positive electrode or the negative electrode. Among these, aluminum foil, aluminum alloy foil, and copper foil are preferable from the viewpoint of balance between high conductivity and cost. In the case of using an aluminum foil as the positive electrode, a known aluminum foil such as 3000 series or 1000 series can be used, but since the present invention aims at improving high rate characteristics, pure aluminum such as JIS A1085 having high conductivity is used. It is preferable to use a system. The thickness of the foil is preferably 5 μm or more and 50 μm or less, and more preferably 10 μm or more and 20 μm or less. If the thickness is less than 5 μm, the strength of the foil is insufficient and it may be difficult to form a resin layer or the like. On the other hand, if it exceeds 50 μm, other components, particularly the active material layer or the electrode material layer, must be thinned. Especially, non-aqueous electrolyte batteries, electric double layer capacitors, lithium ion capacitors and other power storage components In such a case, a sufficient capacity may not be obtained.

(2) Resin layer In this invention, the resin layer which added the electrically conductive material on the electroconductive base material is formed. The method for forming the resin layer is not particularly limited, but a solution, dispersion, paste, or the like containing a resin and a conductive material is applied onto the conductive substrate, and the temperature reached by the conductive substrate is 90 to 230 ° C., and the baking time is 10 It can be formed by performing a baking treatment in ˜60 seconds. The resin used in the present invention is not particularly limited, and various resins such as an acrylic resin, a nitrified cotton resin, or a chitosan resin can be used. In the following description, the number average molecular weight or the weight average molecular weight means that measured by GPC (gel exclusion chromatograph).

<Acrylic resin>
The acrylic resin used in the present invention is a resin formed from a monomer mainly composed of acrylic acid or methacrylic acid, or a derivative thereof. The ratio of the acrylic component in the monomer of the acrylic resin is, for example, 50% by mass or more, and preferably 80% by mass or more. The upper limit is not particularly defined, and the monomer of the acrylic resin may be substantially composed of only the acrylic component. In addition, the acrylic resin monomer may contain one or more acrylic components alone.
Among acrylic resins, an acrylic copolymer containing at least one of methacrylic acid or a derivative thereof and a polar group-containing acrylic compound as a monomer is preferable. This is because the high rate characteristics are further improved by using an acrylic copolymer containing these monomers. Examples of methacrylic acid or derivatives thereof include methacrylic acid, methyl methacrylate, ethyl methacrylate, isopropyl methacrylate and the like. Examples of the polar group-containing acrylic compound include acrylonitrile, methacrylonitrile, acrylamide, and methacrylamide. Further, among the polar group-containing acrylic compounds, an acrylic compound having an amide group is preferable. Examples of the acrylic compound having an amide group include acrylamide, N-methylol acrylamide, and diacetone acrylamide.
The weight average molecular weight of the acrylic resin is not particularly limited, but is, for example, 30,000 to 1,000,000. Specifically, for example, 30,000, 40,000, 60,000, 70,000, 80,000, 90,000, 100,000, 150,000, 200,000, 300,000, 400,000, 500,000, 700,000, 800,000, 900,000, 1 million, and within the range between any two of the numerical values exemplified here There may be. If the molecular weight is too small, the flexibility of the resin layer is low, and if the current collector is wound with a small radius of curvature, the resin layer may crack and the capacity of the battery may decrease, and if the molecular weight is too large, This is because the adhesion tends to be low.

<Nitrated cotton-based resin>
In the present invention, the nitrified cotton-based resin is a resin containing nitrified cotton as a resin component, and may be composed only of nitrified cotton or may contain nitrified cotton and another resin. Nitrified cotton is a kind of cellulose, but is characterized by having a nitro group. Nitrified cotton is a cellulose having a nitro group, but it is not known as a use for electrodes compared to other celluloses such as carboxymethylcellulose (CMC), and has been used as a raw material for resin films and paints. It has been.

  The nitrogen concentration of the nitrified cotton used in the present invention is preferably 10 to 13%, particularly preferably 10.5 to 12.5%. If the nitrogen concentration is too low, it may not be sufficiently dispersed depending on the type of conductive material. If the nitrogen concentration is too high, the nitrified cotton becomes chemically unstable and dangerous for use in batteries. Since the nitrogen concentration depends on the number of nitro groups, the nitrogen concentration can be adjusted by adjusting the number of nitro groups. The viscosity of the nitrified cotton is usually 1 to 6.5 seconds, particularly 1.0 to 6 seconds, and the acid content is 0.006% or less, particularly 0.005% or less, as measured according to JIS K-6703. It is recommended that When deviating from these ranges, the dispersibility of the conductive material and the battery characteristics may deteriorate.

  The nitrified cotton-based resin of the present invention can use only nitrified cotton as a resin component (solid content, the same applies hereinafter), but can also be used in combination with other resin components. It is preferable to contain nitrified cotton in an amount of 50 parts by mass or more, particularly 80 parts by mass or more based on the total resin components. As a result of investigating the resistance of the resin layer by adding a conductive material to various resins, it was found that the resistance of the resin layer can be drastically reduced and sufficient high-rate characteristics can be obtained when containing 50 parts by mass or more of nitrified cotton. It was. This is because if the amount of nitrified cotton is too small, the improvement effect of nitrified cotton blending on the dispersion of the conductive material cannot be obtained, and the addition of 50 parts by mass or more of nitrified cotton can sufficiently reduce the resistance of the resin layer. It is estimated that Moreover, the predominance that the desired uneven | corrugated shape of this invention can be formed by the said mixing | blending is also acquired.

Thus, the nitrified cotton-based resin preferably includes at least one of melamine-based resin, acrylic resin, polyacetal-based resin, and epoxy-based resin, and nitrified cotton.
The number average molecular weight of the melamine resin is, for example, 500 to 50,000, specifically, for example, 500, 1000, 2000, 2500, 3000, 4000, 5000, 10,000, 20,000, and 50,000, It may be within a range between any two of the exemplified numerical values.
The weight average molecular weight of the acrylic resin is, for example, 30,000 to 1,000,000, specifically, for example, 30,000, 40,000, 50,000, 60,000, 80,000, 90,000, 100,000, 150,000. , 200,000, 300,000, 400,000, 500,000, 700,000, 800,000, 900,000, 1 million, and may be in the range between any two of the numerical values exemplified here.
The weight average molecular weight of the polyacetal resin is, for example, 10,000 to 500,000. Specifically, for example, 10,000, 20,000, 30,000, 40,000, 50,000, 60,000, 70,000, 90,000, 90,000 , 100,000, 150,000, 200,000, 500,000, and may be within a range between any two of the numerical values exemplified here.
The weight average molecular weight of the epoxy resin is, for example, 300 to 50,000, specifically, for example, 300,500,1000,2000,3000,4000,5000,10,000,20,000,50,000, It may be within a range between any two of the exemplified numerical values.

The nitrified cotton-based resin further preferably includes at least one of an acrylic resin and a polyacetal-based resin, a melamine-based resin, and nitrified cotton. This is because, in such a combination, the discharge rate characteristics are particularly good and the uneven shape can be formed predominantly.
Moreover, when the total of acrylic resin, polyacetal resin, melamine resin, and nitrified cotton is 100% by mass, the melamine resin is 5 to 55% by mass and the nitrified cotton is 40 to 90% by mass. Is more preferable. This is because the discharge rate characteristics are further improved in this case. Specifically, the content of the melamine resin is, for example, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55% by mass, and between any two of the numerical values exemplified here. It may be within the range. The content of nitrified cotton is 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90% by mass, and is within the range between any two of the numerical values exemplified here. Also good.

<Chitosan resin>
In the present invention, the chitosan resin is a resin containing a chitosan derivative as a resin component. As the chitosan-based resin, one having 100 parts by mass of the chitosan derivative can be used, but it can also be used in combination with other resin components. It is preferable to contain at least 80 parts by mass, particularly 80 parts by mass. The chitosan derivative is, for example, hydroxyalkyl chitosan, and specific examples include hydroxyethyl chitosan, hydroxypropyl chitosan, hydroxybutyl chitosan, glycerylated chitosan and the like. The weight average molecular weight of the chitosan derivative is, for example, 30,000 to 500,000, specifically, for example, 30,000, 40,000, 50,000, 60,000, 80,000, 90,000, 100,000, 150,000. , 200,000, 500,000, and may be within a range between any two of the numerical values exemplified here. The weight average molecular weight means that measured by GPC (gel exclusion chromatograph).
The chitosan resin preferably contains an organic acid. Examples of organic acids include pyromellitic acid and terephthalic acid. The addition amount of the organic acid is preferably 20 to 300% by mass and more preferably 50 to 150% by mass with respect to 100% by mass of the chitosan derivative. If the amount of the organic acid added is too small or too large, it becomes difficult to obtain a desired uneven shape.

<Conductive material>
The resin layer of the present invention has conductivity, but since the resin usually has insulating properties, it is recommended that a conductive material be blended in order to impart conductivity. As the conductive material used in the present invention, known carbon powder, metal powder, and the like can be used. Among them, carbon powder is preferable. As the carbon powder, acetylene black, ketjen black, furnace black, carbon nanotubes and the like can be used. 40-100 mass% is preferable with respect to 100 mass% of resin components of a resin layer, and, as for the addition amount of a electrically conductive material, 40-80 mass% is more preferable. If the amount is less than 40% by mass, the volume resistivity of the resin layer is increased, and if it exceeds 100% by mass, the adhesion to the conductive substrate is lowered. A known method can be used to disperse the conductive material in the resin component liquid of the nitrified cotton-based resin. For example, the conductive material can be dispersed by using a planetary mixer, a ball mill, a homogenizer, or the like.

<Uneven shape>
As shown in FIG. 1, the resin layer 5 of the current collector 1 of the present invention has an uneven shape 6. When the active material layer 9 or the like is formed on the resin layer 5 having the uneven shape 6, the contact area between the resin layer 5 and the active material layer 9 increases and the active material layer 9 enters the resin layer 5. The adhesion between the resin layer 5 and the active material layer 9 is improved.
The ten-point average roughness Rz defined by JIS B 0601 (2001) of the concavo-convex shape 6 is not particularly limited, but is preferably 0.1 to 5 μm. This is because if Rz is too small, the effect of providing the concavo-convex shape cannot be obtained sufficiently, and if Rz is too large, the thickness of the resin layer 5 becomes too large. Specifically, Rz is 0.1, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 4.5, 5 μm. It may be within a range between any two.

For example, as shown in FIG. 3, the resin layer 5 is formed by forming a flat first resin layer 5 a on the conductive substrate 3, and a second resin layer 5 b having a concavo-convex shape 6 on the first resin layer 5 a. Can be formed. The term “flat” as used in the present invention refers to the surface state other than the portion designed to have a concavo-convex shape. Any surface may be used as long as it is a surface formed by a resin provided in the designed cell, and it does not mean a state in which an actual resin layer is viewed in detail in micro units.
The 1st resin layer 5a is formed by apply | coating resin to the whole surface of the base material 3 by a roll-to-roll system, for example using a gravure printing method or a silk screen printing method. The thickness of the 1st resin layer 5a is 0-3 micrometers, for example, Preferably, it is 0-2.0 micrometers. Specifically, the thickness of the first resin layer 5a is, for example, 0, 0.5, 1, 1.5, 2, 2.5, or 3 μm, and is between any two of the numerical values exemplified here. It may be within the range.
The second resin layer 5b is formed, for example, by applying a resin in a concavo-convex shape on the first resin layer 5a by a roll-to-roll method using a gravure printing method or a silk screen printing method. The thickness of the 2nd resin layer 5b is 0.1-3 micrometers, for example, Preferably, it is 0.35-1.5 micrometers. Specifically, the thickness of the second resin layer 5b is, for example, 0.1, 0.5, 1, 1.5, 2, 2.5, 3 μm, and any two of the numerical values exemplified here are used. It may be within the range between.
The thickness of the resin layer can be calculated from the difference in thickness between the resin layer forming part and the non-formed part (part only of the aluminum foil) using a film thickness measuring instrument Keitaro G (manufactured by Seiko em).
The materials of the first resin layer 5a and the second resin layer 5b may be the same or different from each other. For example, when the active material paste is an alkaline aqueous active material paste, since the base material may be corroded when the paste and the Al base material are brought into direct contact, the first resin layer 5a is to protect the Al base material. It is preferably formed of a resin having a barrier function to the alkaline aqueous active material paste.

  As another method for forming the resin layer 5 having the concavo-convex shape 6, as shown in FIG. After forming, the resin liquid layer 11 flows and enters the concave and convex valleys to form a shape as shown in FIG. 4B. By performing heat treatment in this state, the concave and convex shape is obtained. The resin layer 5 is formed. According to this method, since the resin layer 5 having an uneven shape can be formed by one printing, the number of manufacturing steps can be reduced. The amount of the resin that enters the concave and convex valleys can be adjusted as appropriate by changing the viscosity of the resin and the time for leaving it.

The irregular shape 6 may be either a regular pattern in which irregularities are formed with a constant pattern or an irregular pattern in which irregularities are formed with a pattern having no irregularities, but the irregular shape 6 is regular. If it is a pattern, the stress applied to the current collector can be uniformly dispersed by making it an appropriate shape, and it is possible to suppress cracking and distortion of the conductive substrate, etc., so durability It can be suitably employed as a good current collector.
Hereinafter, various regularity patterns will be described with reference to FIGS. 5 to 9 are plan views of the current collector 1 as viewed from the resin layer 5 side. 5-9, the pattern of the 2nd resin layer 5b is shown by the hatching part. The white portion is the first resin layer 5a or the exposed conductive substrate 3. The exposed case is, for example, a state where the first resin layer 5a is not formed in the state of FIG. 3, and the following description includes a case where the first resin layer is not formed. In this case, since the resin layer is only the second resin layer 5b, the surface of the conductive substrate is partially exposed. Therefore, if an active material layer is further formed using the current collector of this exposed structure, an active material layer is also formed in the exposed portion, so that a large amount of active material can be secured and electrical characteristics can be improved. . Here, the description proceeds using the term “second resin layer”, but the regular pattern may be formed by the method described with reference to FIGS.

  In FIG. 5, the uneven shape 6 is a grid shape that intersects at 90 degrees. The left and right figures have a negative / positive relationship, and either may be adopted as the regularity pattern. In one example, the width of the line L is 0.05 to 3 mm, the width of the space S is 0.05 to 3 mm, and the pitch is 0.1 to 6 mm.

  In FIG. 6, the uneven shape 6 is a grid shape that intersects at 45 degrees. The left and right figures have a negative / positive relationship, and either may be adopted as the regularity pattern. In one example, the width of the line L is 0.05 to 1 mm, the width of the space S is 0.05 to 1 mm, and the pitch is 0.1 to 2 mm.

  In FIG. 7, the uneven shape 6 is a honeycomb shape. The left and right figures have a negative / positive relationship, and either may be adopted as the regularity pattern. In one example, the width of the line L is 0.05 to 3 mm, the width of the space S is twice that of L, and the pitch is three times that of L.

  In FIG. 8, the uneven shape 6 is a dot shape. The left and right figures have a negative / positive relationship, and either may be adopted as the regularity pattern. As a dot arrangement method, there is a method of arranging circular dots one by one at the center of gravity of each equilateral triangle obtained when a regular hexagon having a side length of a (mm) is divided into six. The diameter L of each dot is L = (a / √3) * θ where the inscribed circle reduction rate is θ. The inscribed circle reduction rate is, for example, 0.5 to 1. In one example, a is 1 to 6 mm and the diameter L is 0.3 to 3.5 mm.

  In FIG. 9, the uneven shape 6 is a dot shape. The left and right figures have a negative / positive relationship, and either may be adopted as the regularity pattern. An example of the dot arrangement method is a method of arranging a circular dot having a diameter L at the apex of an equilateral triangle having a side length of a (mm). The diameter L of each dot is L = a * θ where θ is the reduction ratio. The reduction rate is, for example, 0.5-1. In one example, a is 1 to 6 mm and the diameter L is 0.5 to 6 mm.

  Although the manufacturing method of the current collector of the present invention is not particularly limited, when the resin layer is formed on the conductive substrate, the conductive substrate is improved so that the adhesion of the surface of the conductive substrate is improved. It is also effective to perform a known pretreatment. In particular, when a metal foil produced by rolling is used, rolling oil or wear powder may remain, and adhesion can be improved by removing it by degreasing or the like. The adhesion can also be improved by a dry activation treatment such as a corona discharge treatment.

Electrode Structure The electrode structure of the present invention can be obtained by forming an active material layer or an electrode material layer on at least one surface of the current collector of the present invention. The electrode structure for an electrical storage component in which the electrode material layer is formed will be described later. First, in the case of an electrode structure in which an active material layer is formed, an electrode structure (battery component) for a non-aqueous electrolyte battery, for example, a lithium ion secondary battery, using the electrode structure, a separator, a non-aqueous electrolyte solution, etc. Can be manufactured). In the electrode structure for a nonaqueous electrolyte battery and the nonaqueous electrolyte battery of the present invention, a member other than the current collector can be a known nonaqueous battery member. Here, the active material layer formed as an electrode structure in the present invention may be conventionally proposed for non-aqueous electrolyte batteries. For example, the current collector of the present invention using aluminum as the positive electrode, LiCoO ₂ , LiMnO ₂ , LiNiO ₂ or the like as the active material, carbon black such as acetylene black as the conductive material, and PVDF as a binder The positive electrode structure of the present invention can be obtained by applying and drying the paste dispersed in the powder. In the case of a negative electrode structure, for example, graphite, graphite, mesocarbon microbeads or the like are used as the active material for the current collector of the present invention using copper as the conductive substrate, and these are thickeners. After dispersion in CMC, the negative electrode structure of the present invention can be obtained by applying and drying a paste mixed with SBR as a binder as an active material layer forming material.

Nonaqueous electrolyte battery The present invention may be a nonaqueous electrolyte battery. In this case, there is no particular limitation other than using the current collector of the present invention. For example, the non-aqueous electrolyte battery of the present invention is sandwiched between separators impregnated with an electrolyte for a non-aqueous electrolyte battery having a non-aqueous electrolyte between the positive electrode structure and the negative electrode structure having the current collector of the present invention as a constituent element. A water electrolyte battery can be constructed. As the nonaqueous electrolyte and the separator, those used for known nonaqueous electrolyte batteries can be used. As the electrolytic solution, carbonates or lactones can be used as a solvent. For example, a solution obtained by dissolving LiPF ₆ or LiBF ₄ as an electrolyte in a mixed solution of EC (ethylene carbonate) and EMC (ethyl methyl carbonate) is used. Can do. As the separator, for example, a film having a microporous made of polyolefin can be used.

Power storage components (electric double layer capacitors, lithium ion capacitors, etc.)
The electric double layer capacitor, lithium ion capacitor, etc. of the present invention can also be applied to power storage components such as electric double layer capacitors and lithium ion capacitors that require high-speed charge / discharge at a large current density. is there. The electrode structure for a power storage component of the present invention is obtained by forming an electrode material layer on the current collector of the present invention. By using this electrode structure and a separator, an electrolytic solution, etc., an electric double layer capacitor, a lithium ion capacitor, etc. A power storage component can be manufactured. In the electrode structure and power storage component of the present invention, members other than the current collector can be members for known electric double layer capacitors or lithium ion capacitors.

  The electrode material layer can be made of an electrode material, a conductive material, and a binder for both the positive electrode and the negative electrode. In the present invention, an electricity storage component can be obtained after forming the electrode material layer on at least one side of the current collector of the present invention to form an electrode structure. Here, as the electrode material, those conventionally used as electrode materials for electric double layer capacitors and lithium ion capacitors can be used. For example, carbon powder or carbon fiber such as activated carbon or graphite can be used. As the conductive material, carbon black such as acetylene black can be used. As the binder, for example, PVDF (polyvinylidene fluoride) or SBR (styrene butadiene rubber) can be used. In addition, the electric storage component of the present invention can constitute an electric double layer capacitor or a lithium ion capacitor by fixing the electrode structure of the present invention with a separator interposed therebetween and allowing the electrolyte to penetrate into the separator. As the separator, for example, a polyolefin microporous film, an electric double layer capacitor nonwoven fabric, or the like can be used. For example, carbonates and lactones can be used as the solvent in the electrolyte, and the electrolyte includes tetraethylammonium salt and triethylmethylammonium salt as the cation, and hexafluorophosphate and tetrafluoroborate as the anion. Can be used. A lithium ion capacitor is a combination of a negative electrode of a lithium ion battery and a positive electrode of an electric double layer capacitor. These production methods can be carried out according to known methods, except that the current collector of the present invention is used, and are not particularly limited.

1: Current collector
3: Conductive substrate 5: Resin layer (resin layer for current collector)
5a: first resin layer 5b: second resin layer 7: electrode structure 9: active material layer or electrode material layer 11: resin liquid layer

Claims (9)

A current collector having a conductive resin layer formed on at least one side of a conductive substrate,
The surface of the resin layer is a current collector having an uneven shape. The current collector according to claim 1, wherein the uneven shape has a ten-point average roughness Rz of 0.1 to 5 μm. The resin layer includes a first resin layer and a second resin layer in order from the conductive substrate side, the first resin layer is substantially flat, and the uneven shape is provided on the second resin layer. The current collector according to claim 1 or 2. The current collector according to claim 3, wherein the first resin layer and the second resin layer are made of different materials. The current collector according to claim 1, wherein the uneven shape is a regular pattern. The current collector according to claim 5, wherein the regular pattern has a lattice shape, a honeycomb shape, or a dot shape. The current collector according to claim 5 or 6, wherein the regular pattern has a pitch of 0.1 to 0.6 mm. An electrode structure comprising an active material layer or an electrode material layer on the resin layer of the current collector according to claim 1. A nonaqueous electrolyte battery or a power storage component comprising the electrode structure according to claim 8.