JP2020107411A - Separator having fine pattern, wound body, and nonaqueous electrolyte battery and manufacturing method thereof - Google Patents

Abstract

To provide a separator capable of preventing a separator-wound body from being deformed due to pulling out of a core material.SOLUTION: A separator 10 used in a nonaqueous electrolyte battery and capable of being wound while one side 11 is on an inner side includes at least one low friction area 12 having a friction force of 900 gf or less, the ratio of the area of the low friction area 12 occupied on the area of the one face 11 being 0.01% or more and 10% or less.SELECTED DRAWING: Figure 1

Description

The present invention relates to a separator having a fine pattern, a wound body, a non-aqueous electrolyte battery, a manufacturing method thereof, and the like.

2. Description of the Related Art With the recent development of electronic technology or increasing interest in environmental technology, various electrochemical devices have been used. A non-aqueous electrolyte battery, which is a typical example of an electrochemical device, in particular, a tin-ion secondary battery has hitherto been mainly used as a power source for small devices, but in recent years, a power source for large devices, for example, a power source for hybrid vehicles or electricity. It is also drawing attention as a power source for automobiles.
Inside the non-aqueous electrolyte battery, a laminate of a positive electrode, a separator, and a negative electrode, or a wound product obtained by winding such a laminate (hereinafter may be referred to as “wound type electrode body”) is housed. .. Of these, the separator has a function of preventing direct contact between the positive and negative electrodes and a function of allowing ions to permeate through the non-aqueous electrolyte retained in the microporous membrane. Note that the separator is often used, stored, transported, or the like in the state of a wound body (hereinafter sometimes referred to as “separated wound body”).

Here, it has been proposed to provide an uneven shape based on a predetermined purpose on at least one surface of a separator for a non-aqueous electrolyte battery. (See, for example, Patent Documents 1 to 5).

JP, 2016-184710, A JP, 2013-211192, A Patent No. 4529903 JP-A-5-151951 International Publication No. 2008/053898

When a wound-type electrode body or a separate wound body is produced, the laminate or the separator is wound while being applied with tension. Therefore, as the number of windings increases, the core material is more easily compressed by the laminate or the separator. The frictional force between the laminate or the separator and the core material is easily increased. Particularly in recent years, from the viewpoint of increasing the capacity of the battery or increasing the efficiency of the battery manufacturing process, it is often desired to elongate the laminate or the separator, and the number of windings tends to increase, so the frictional force is likely to be increased. It is in.
When the frictional force is excessively high, when the core material is pulled out at a necessary timing after winding, the laminate or the separator is pulled together in the pulling direction, and as a result, the wound electrode body or the separation wound body is formed. It may project (deform) like a bamboo shoot. Such deformation is likely to cause a large loss in manufacturing the non-aqueous electrolyte battery.
Under the above circumstances, Patent Documents 1 to 5 have not examined the viewpoint of preventing the deformation of the wound electrode body or the separation wound body due to the pulling out of the core material.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a separator that can prevent deformation of a wound electrode body or a separate wound body due to pulling out of a core material. .. Another object of the present invention is to provide a wound body including such a separator, a non-aqueous electrolyte battery, a manufacturing method thereof, and the like.

The present inventors have conducted studies to solve the above problems, and have completed the present invention by finding that the above problems can be solved by satisfying the following requirements. That is, the present invention is as follows.

[1]
A separator that is used in a non-aqueous electrolyte battery and that can be wound with one side facing inward,
It has at least one low friction area where the friction force is 900 gf or less,
The ratio of the area of the low-friction region to the area of the one surface is 0.01% or more and 10% or less.
[2]
The separator according to [1], wherein the frictional force in the low friction region is 300 gf or more.
[3]
The separator has a high friction area around the low friction area, the friction force of which exceeds 900 gf.
The separator according to [1] or [2], wherein the difference between the frictional force in the low frictional region and the frictional force in the high frictional region is 10 gf or more and 600 gf or less.
[4]
The low friction region includes an end region within 10% from an end in the flow direction (MD) of the separator, based on the length in the flow direction (MD) of the separator, [1] to [1]. [3] The separator according to any one of [3].
[5]
The said low friction area|region is a separator as described in any one of [1]-[4] including the innermost area|region located in the innermost side, when the said one surface is turned inside, and the said separator is wound.
[6]
The separator according to any one of [1] to [5], wherein the low-friction region is composed of an uneven region.
[7]
A wound body obtained by winding the separator according to any one of [1] to [6] as a repeating unit.
[8]
A non-aqueous electrolyte containing a positive electrode, a separator according to any one of [1] to [6], and a laminate in which a negative electrode is laminated or a wound product obtained by winding the laminate, and a non-aqueous electrolyte. battery.
[9]
Used in a non-aqueous electrolyte battery, and a method for producing a windable separator with one side inside,
A step of preparing a raw fabric; and
At least one low-friction region having a friction force of 900 gf or less is physically formed so that the ratio of the area of the low-friction region to the area of one side of the original fabric is 0.01% or more and 10% or less. A method for manufacturing a separator, including the step of manufacturing the separator.
[10]
A method for producing a non-aqueous electrolyte battery, comprising the step of producing a non-aqueous electrolyte battery using the separator produced by the method described in [9].
[11]
Used in a non-aqueous electrolyte battery, and a manufacturing apparatus for manufacturing a separator that can be wound with one side inside,
At least one low-friction region having a friction force of 900 gf or less is physically formed so that the ratio of the area of the low-friction region to the area of one side of the raw fabric is 0.01% or more and 10% or less, A separator manufacturing apparatus for manufacturing the separator.
[12]
A non-aqueous electrolyte battery manufacturing apparatus, comprising the apparatus according to claim 11, and manufacturing a non-aqueous electrolyte battery using the separator.

According to the present invention, by winding the separator so that the low friction region is located at the innermost position, the low friction region can be positioned in a region where the separator and the core material are adjacent to each other. Therefore, even if the number of windings is increased, the frictional force between the separator and the core material can be maintained in a relatively low range, whereby the core material can be easily pulled out after winding, and as a result, It is possible to prevent the separation winding body from being deformed by pulling out the core material. Moreover, according to the present invention, the area ratio of the low-friction region is suppressed within the above range, so that in the outer side of the core material (the region where the layers face each other), suitable friction between the layers is secured. This can also prevent the deformation of the separation wound body due to the pulling out of the core material.
Further, according to the present invention, by producing a wound type electrode body using the above separator, even if the core material is not to be extracted from the separation wound body, the wound type When pulling out the core material from the electrode body, the deformation of the wound type electrode body can be prevented.
Furthermore, according to the present invention, it is also possible to provide a wound body (separated wound body) and a non-aqueous electrolyte battery including such a separator, a method for producing the same, and the like.

6A and 6B are diagrams illustrating a configuration example of a top surface and a side surface of a separator according to one embodiment of the present invention. The figure which shows the structural example of the cross section of the separate winding body which concerns on 1 aspect of this invention. The figure which shows the structural example at the time of winding the separator which concerns on 1 aspect of this invention. The flowchart which shows an example of the manufacturing method of the separator which concerns on 1 aspect of this invention. The figure which shows the structural example of the manufacturing apparatus of the separator which concerns on 1 aspect of this invention. The figure which shows the structural example of the manufacturing apparatus of the non-aqueous electrolyte battery which concerns on one aspect of this invention. The figure for demonstrating an example of the separator which concerns on the other aspect of this invention.

Hereinafter, modes for carrying out the present invention (hereinafter, simply referred to as “embodiments”) will be described. The following embodiment is one aspect of the present invention, and does not purport to limit the present invention to the following embodiment. Therefore, the following embodiments can be appropriately modified and implemented within the scope of the gist of the present invention. Unless otherwise specified, the term “to” in the present specification means that the numerical values described before and after the “to” are included as the upper limit value and the lower limit value. The configurations illustrated in the drawings, such as the scale, the shape, and the length, may be exaggerated for the purpose of describing the invention in detail.

[Embodiment 1]
Embodiment 1 is a separator used for a non-aqueous electrolyte battery. The separator includes a base material and a pattern provided on at least one surface of the base material. This type of pattern is also called a fine pattern because it has a major axis length in the unit of micrometers. The pattern may be provided on the entire main surface or may be provided on only a part of the main surface. Further, both the aspect in which the pattern is provided only on one of the main surfaces facing each other and the aspect in which the pattern is provided on both the main surfaces are included in the scope of the present invention. When the substrate includes a plurality of patterns, those patterns may be the same as or different from each other.
In the present specification, the “main surface” means a surface having at least three sides and having the largest area among the surfaces of the base material. That is, the “main surface” in the present specification means a surface facing the positive electrode or the negative electrode when incorporated in the non-aqueous electrolyte battery.
Hereinafter, various elements related to the first embodiment will be sequentially described.

[Substrate (original)]
As the base material, a material having high ion permeability and having a function of electrically isolating the positive electrode and the negative electrode, for example, a known microporous membrane used in a non-aqueous electrolyte battery can be used.
Specifically, such as polyolefins (polyethylene (PE), polypropylene (PP), etc.), polyesters, polyimides, polyamides, polyurethanes, etc., are stable to the non-aqueous electrolyte in the battery and are electrochemically stable. A microporous membrane or a non-woven fabric composed of a stable material can be used as the substrate.
Further, the substrate has a function of closing its pores at a temperature of preferably 80° C. or higher (more preferably 100° C. or higher), and preferably 180° C. or lower (more preferably 150° C. or lower) (that is, a shutdown function). ) Are preferred. Therefore, the substrate has a melting temperature, that is, a melting temperature range measured using a differential scanning calorimeter (DSC) according to JIS K 7121, preferably 80° C. or higher (more preferably 100° C. or higher). ), and it is more preferable to use a microporous membrane or a nonwoven fabric containing a polyolefin having a temperature of 180°C or lower (more preferably 150°C or lower). In this case, the microporous membrane or the non-woven fabric as the base material may be composed of, for example, PE alone, PP alone, or may contain two or more kinds of materials.
The base material is not limited to a single material, and may include a plurality of layers. Therefore, the base material is a laminate of a microporous membrane made of PE and a microporous membrane made of PP (PP/PE/PP three-layer laminate, etc.), a microporous membrane made of PE and a microporous membrane made of polyimide. It may be a laminated body or the like.
Representative examples of the base material include a polyolefin microporous membrane, and a polyolefin microporous membrane having an inorganic layer on at least one surface.

(Polyolefin microporous membrane)
The polyolefin microporous film contains a polyolefin resin. The polyolefin resin is not particularly limited, and examples thereof include homopolymers of ethylene, propylene, 1-butene, 4-methyl-1-pentene, 1-hexene, 1-octene, and the like, and copolymers thereof, multistage polymers and the like. Can be used. More specifically, but not limited to, low density polyethylene, linear low density polyethylene, medium density polyethylene, high density polyethylene, ultra high molecular weight polyethylene, isotactic polypropylene, atactic polypropylene, ethylene-propylene random copolymer, polybutene. , And ethylene propylene rubber.
Among them, when the application to a non-aqueous electrolyte battery is assumed, a resin having a low melting point and a high strength and having high density polyethylene as a main component is preferable as the polyolefin resin.

It is more preferable to use polypropylene and a polyolefin resin other than polypropylene in combination. By using such a polyolefin resin, the heat resistance of the separator tends to be further improved. The three-dimensional structure of polypropylene is not particularly limited, and examples thereof include isotactic polypropylene, syndiotactic polypropylene, and atactic polypropylene.

As content of polypropylene, 1-35 mass% is preferable with respect to 100 mass% of polyolefin resin, 3-20 mass% is more preferable, 4-10 mass% is still more preferable. When the polypropylene content is within the above range, higher heat resistance and a better shutdown function tend to be compatible.

The polyolefin resin other than polypropylene is not particularly limited, but examples thereof include those mentioned above, and among them, polyethylene, polybutene, ethylene-propylene random copolymer and the like are preferable. In particular, low density polyethylene, linear low density polyethylene, medium density polyethylene, high density polyethylene, and ultrahigh molecular weight polyethylene are more preferable from the viewpoint of shutdown characteristics. From the viewpoint of strength, polyethylene having a density of 0.93 g/cm ³ or more measured according to JIS K 7112 is also preferable.
The polyolefin resins may be used alone or in combination of two or more.

The content of the polyolefin resin is preferably 50% by mass or more and 100% by mass or less, more preferably 60% by mass or more and 100% by mass or less, and further preferably 70% by mass or more and 100% by mass or less with respect to 100% by mass of the base material. preferable. When the content of the polyolefin resin is within the above range, the shutdown performance tends to be further improved when used as a separator for a non-aqueous electrolyte battery.

The viscosity average molecular weight of the polyolefin resin is preferably from 30,000 to 12,000,000, more preferably from 50,000 to 2,000,000, still more preferably from 100,000 to 1,000,000. When the viscosity average molecular weight is 30,000 or more, the melt tension at the time of melt molding becomes large, the moldability of the base material becomes good, and the base material tends to have higher strength due to the entanglement of the polymers. On the other hand, when the viscosity average molecular weight is 12,000,000 or less, it becomes easy to uniformly melt and knead, and the sheet tends to be excellent in moldability, particularly in thickness stability. Further, when the viscosity average molecular weight is 1,000,000 or less, pores are likely to be clogged when the temperature rises, and a good shutdown function tends to be obtained. Note that, for example, instead of using a polyolefin having a viscosity average molecular weight of less than 1,000,000 alone, it is a mixture of a polyolefin having a viscosity average molecular weight of 2,000,000 and a polyolefin having a viscosity average molecular weight of 270,000, and the viscosity average molecular weight is less than 1,000,000. A polyolefin resin mixture may be used.

The substrate can contain any additive. The additives are not particularly limited, but include, for example, polymers other than polyolefin resins; inorganic particles; resin fine particles; phenol-based, phosphorus-based, sulfur-based antioxidants, etc.; metal soaps such as calcium stearate and zinc stearate; Examples thereof include ultraviolet absorbers, light stabilizers, antistatic agents, antifogging agents, and coloring pigments.

When the substrate contains inorganic particles and/or resin fine particles, the polyolefin microporous film may contain inorganic particles and/or resin fine particles.

The inorganic particles are preferably sodium oxide, potassium oxide, magnesium oxide, calcium oxide, barium oxide, lanthanum oxide, cerium oxide, strontium oxide, vanadium oxide, SiO ₂ —MgO (magnesium silicate), SiO ₂ —CaO( Calcium silicate), hydrotalcite, sodium carbonate, potassium carbonate, magnesium carbonate, calcium carbonate, barium carbonate, lanthanum carbonate, cerium carbonate, basic titanate, basic silicotitanate, basic copper acetate, basic sulfuric acid Lead, layered double hydroxide (Mg-Al type, Mg-Fe type, Ni-Fe type, Li-Al type), layered double hydroxide-alumina silica gel composite, boehmite, alumina, zinc oxide, lead oxide, Anion adsorbent such as iron oxide, iron oxyhydroxide, hematite, bismuth oxide, tin oxide, titanium oxide, zirconium oxide, zirconium phosphate, titanium phosphate, apatite, non-basic titanate, niobate, niobium -Cationic adsorbents such as titanates, zeolites, calcium sulfate, magnesium sulfate, aluminum sulfate, gypsum, carbonates such as barium sulfate, and sulfates, alumina trihydrate (ATH), fumed silica, precipitated silica , Oxide ceramics such as zirconia and yttria, nitride ceramics such as silicon nitride, titanium nitride and boron nitride, silicon carbide, kaolinite, talc, dikite, nacrite, halloysite, pyrophyllite, montmorillonite, sericite , Amethite, layered silicates such as bentonite, asbestos, diatomaceous earth, glass fibers, synthetic layered silicates such as mica or fluoromica, and zinc borate. These may be used alone or in combination of two or more.

As resin fine particles, it is made of an electrochemically stable resin that has heat resistance and electrical insulation properties, is stable to non-aqueous electrolytes, and is difficult to undergo redox in the operating voltage range of non-aqueous electrolyte batteries. Preferably. As the resin for forming such resin fine particles, styrene resin (polystyrene etc.), styrene-butadiene rubber, acrylic resin (polymethylmethacrylate etc.), polyalkylene oxide (polyethylene oxide etc.), fluororesin (polyvinylidene fluoride). Etc.) and a cross-linked product of at least one resin selected from the group consisting of derivatives thereof, urea resins, polyurethane and the like. As the resin fine particles, the resins exemplified above may be used alone or in combination of two or more. Further, the resin fine particles may contain a known additive that can be added to the resin, such as an antioxidant, if necessary.

The form of the inorganic particles or resin fine particles may be any of plate-like, scale-like, needle-like, columnar, spherical, polyhedral, and lump-like forms. The inorganic particles or resin fine particles having the above-mentioned form may be used alone or in combination of two or more kinds. From the viewpoint of improving the transparency, a polyhedral shape having a plurality of surfaces is preferable.

The average particle diameter (D50) of the inorganic particles or resin particles is preferably 0.1 μm to 4.0 μm, more preferably 0.2 μm to 3.5 μm, and 0.4 μm. More preferably, it is about 3.0 μm. By adjusting the average particle diameter within such a range, heat shrinkage at high temperature tends to be further suppressed.

The total content of these additives is preferably 20 parts by mass or less, more preferably 10 parts by mass or less, still more preferably 5 parts by mass or less, based on 100 parts by mass of the base material. The lower limit of the total content is not particularly limited, and can be, for example, more than 0 parts by mass with respect to 100 parts by mass of the base material.

A polyolefin microporous membrane having an inorganic layer on at least one surface is also included in the scope of the base material envisioned by the present invention. When such a base material is used, a separator having an inorganic coating layer formed on at least one surface is formed.
An inorganic layer may be provided on the surface of the polyolefin microporous film on which the pattern is formed, or an inorganic layer may be provided on the surface opposite to the surface on which the pattern is formed. Further, on the surface on which the pattern is formed, the inorganic layer may be provided so as to overlap the pattern, or the inorganic layer may be provided so as not to overlap the pattern.
However, when an inorganic layer is provided on the polyolefin microporous film, the inorganic layer is preferably provided so as not to overlap the pattern among the surfaces on which the pattern is formed, and the inorganic layer on the side opposite to the surface on which the pattern is formed. More preferably, it is provided on the surface.

(Inorganic layer)
The inorganic layer is not particularly limited, and examples thereof include those containing an inorganic filler and a resin binder.
Among these, as the inorganic filler, those exemplified above as the inorganic particles can be preferably used. Among them, aluminum oxide compounds such as alumina and boehmite, or ion exchange capacities such as kaolinite, dikite, nacrite, halloysite and pyrophyllite, from the viewpoint of improving electrochemical stability and heat resistance of the microporous membrane. Aluminum silicate compounds that do not have are preferred. Aluminum hydroxide oxide is preferable as the aluminum oxide compound. As the aluminum silicate compound having no ion exchange ability, kaolin mainly composed of kaolin minerals is preferable because it is inexpensive and easily available. Kaolin includes wet kaolin and calcined kaolin obtained by calcining it. Calcined kaolin releases impurities in addition to water of crystallization during the calcining process, so that it has electrochemical stability. Is particularly preferable.

The shape of the inorganic filler is not particularly limited, and examples thereof include a plate shape, a scale shape, a needle shape, a columnar shape, a spherical shape, a polyhedral shape, and a lump shape. Good. Among them, a polyhedron shape having a plurality of surfaces, a columnar shape, and a spindle shape are preferable. By using such an inorganic filler, the permeability tends to be further improved.

As content of an inorganic filler, with respect to 100 mass% of an inorganic layer, 50 mass% or more and less than 100 mass% are preferable, 70 mass% or more and 99.99 mass% or less are more preferable, 80 mass% or more and 99.9 mass%. % Or less is more preferable, and 90% by mass or more and 99% by mass or less is particularly preferable. When the content of the inorganic filler is within the above range, the binding property of the inorganic filler, the heat resistance, and the permeability in the case of a multilayer microporous film tend to be further improved.

The resin binder is not particularly limited, but it is preferable to use one that is insoluble in the non-aqueous electrolyte and is electrochemically stable in the range of use of the lithium ion secondary battery. The resin binder is not particularly limited, but examples thereof include polyolefins such as polyethylene and polypropylene; fluorine-containing resins such as polyvinylidene fluoride and polytetrafluoroethylene; vinylidene fluoride-hexafluoropropylene-tetrafluoroethylene copolymerization Fluorine-containing rubber such as polymer and ethylene-tetrafluoroethylene copolymer; styrene-butadiene copolymer, and its hydride, acrylonitrile-butadiene copolymer, and its hydride, acrylonitrile-butadiene-styrene copolymer, and Its hydride, methacrylic acid ester-acrylic acid ester copolymer, styrene-acrylic acid ester copolymer, acrylonitrile-acrylic acid ester copolymer, ethylene propylene rubber, polyvinyl alcohol, rubbers such as polyvinyl acetate; ethyl cellulose, Cellulose derivatives such as methyl cellulose, hydroxyethyl cellulose, carboxymethyl cellulose; resins having a melting point and/or glass transition temperature of 180° C. or higher such as polyphenylene ether, polysulfone, polyether sulfone, polyphenylene sulfide, polyetherimide, polyamideimide, polyamide and polyester. Etc.

When polyvinyl alcohol is used as the resin binder, the saponification degree is preferably 85% or more and 100% or less, more preferably 90% or more and 100% or less, further preferably 95% or more and 100% or less, and 99% or more 100%. The following are particularly preferred. When the degree of saponification of PVA is 85% or more, the temperature at which the separator short-circuits (short-circuit temperature) is improved, and better safety performance tends to be obtained.

The polymerization degree of polyvinyl alcohol is preferably 200 or more and 5,000 or less, more preferably 300 or more and 4,000 or less, and further preferably 500 or more and 3,500 or less. When the degree of polymerization is 200 or more, a small amount of polyvinyl alcohol can firmly bond the inorganic filler such as calcined kaolin to the inorganic layer, and suppress the increase in air permeability of the base material while maintaining the mechanical strength of the inorganic layer. Tend to be able to. Further, when the degree of polymerization is 5,000 or less, gelation or the like tends to be prevented when the coating liquid is prepared.

As the resin binder, a resin latex binder is preferable. By using the resin latex binder, the ion permeability is less likely to decrease and high output characteristics tend to be easily obtained. In addition, even if the temperature rises rapidly during abnormal heat generation, smooth shutdown characteristics are exhibited, and high safety tends to be obtained.

The resin latex binder is not particularly limited, but for example, from the viewpoint of improving electrochemical stability and binding property, an aliphatic conjugated diene monomer, an unsaturated carboxylic acid monomer, and an aliphatic binder. Emulsifying a conjugated diene monomer and/or unsaturated carboxylic acid monomer and an aliphatic conjugated diene monomer and/or another monomer copolymerizable with the unsaturated carboxylic acid monomer Those obtained by polymerization are preferred. The emulsion polymerization method is not particularly limited, and a known method can be used. The addition method of the monomer and other components is not particularly limited, and any one of a batch addition method, a divided addition method, and a continuous addition method can be adopted, and one-step polymerization, two-step polymerization or Any of multi-step polymerization and the like can be adopted.

The aliphatic conjugated diene-based monomer is not particularly limited, but examples thereof include 1,3-butadiene, 2-methyl-1,3-butadiene, 2,3-dimethyl-1,3 butadiene, and 2-chloro-1. , 3-butadiene, substituted linear conjugated pentadienes, substituted and side chain conjugated hexadienes, and the like. These may be used alone or in combination of two or more. Among the above, 1,3-butadiene is particularly preferable.

The unsaturated carboxylic acid monomer is not particularly limited, and examples thereof include mono- or dicarboxylic acids (anhydrides) such as acrylic acid, methacrylic acid, crotonic acid, maleic acid, fumaric acid and itaconic acid. These may be used alone or in combination of two or more. Among the above, acrylic acid and methacrylic acid are particularly preferable.

Other monomers copolymerizable with the aliphatic conjugated diene-based monomer and/or the unsaturated carboxylic acid monomer are not particularly limited, but include, for example, aromatic vinyl-based monomers and vinyl cyanide. Examples thereof include system monomers, unsaturated carboxylic acid alkyl ester monomers, hydroxyalkyl group-containing unsaturated monomers and unsaturated carboxylic acid amide monomers. These may be used alone or in combination of two or more.
Of these, unsaturated carboxylic acid alkyl ester monomers are particularly preferable. The unsaturated carboxylic acid alkyl ester monomer is not particularly limited, and examples thereof include methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, butyl acrylate, glycidyl methacrylate, dimethyl fumarate, diethyl fumarate, dimethyl maleate, diethyl. Examples thereof include maleate, dimethyl itaconate, monomethyl fumarate, monoethyl fumarate, and 2-ethylhexyl acrylate. These may be used alone or in combination of two or more. Among the above, methyl methacrylate is particularly preferable.
In addition to these monomers, in order to improve various quality and physical properties, monomer components other than the above may be further used.

The average particle size of the resin binder is preferably 50 to 800 nm, more preferably 60 to 700 nm, and even more preferably 80 to 500 nm. When the average particle diameter of the resin binder is 50 nm or more, when the inorganic layer is laminated on at least one surface of the microporous polyolefin membrane, ion permeability is unlikely to be lowered and high output characteristics tend to be easily obtained. In addition, even if the temperature rises rapidly during abnormal heat generation, smooth shutdown characteristics are exhibited, and high safety tends to be obtained. When the average particle diameter of the resin binder is 800 nm or less, good binding properties are exhibited, and when a multilayer microporous film is formed, heat shrinkage becomes good and safety tends to be excellent. The average particle size of the resin binder can be controlled by adjusting the polymerization time, the polymerization temperature, the raw material composition ratio, the raw material feeding order, the pH and the like.

The layer thickness of the inorganic layer is preferably 1 to 50 μm, more preferably 1.5 to 20 μm, further preferably 2 to 10 μm, further preferably 3 to 10 μm, and particularly preferably 3 to 7 μm. When the layer thickness of the inorganic layer is 1 μm or more, the heat resistance and insulating property of the base material tend to be further improved. Moreover, when the layer thickness of the inorganic layer is 50 μm or less, the battery capacity and the permeability tend to be further improved.

The layer density of the inorganic layer is preferably ^{0.5~2.0g / cm 3, 0.7~1.5g / cm} 3 is more preferable. When the layer density of the inorganic layer is 0.5 g/cm ³ or more, the heat shrinkage rate at high temperature tends to be good. Further, when the layer density of the inorganic layer is 2.0 g/cm ³ or less, the air permeability tends to be further reduced.

(Separator)
The separator includes the above-mentioned base material. The porosity of the separator is preferably 30% or more, and preferably 40% or more, in a dried state of the separator, in order to secure a holding amount of the non-aqueous electrolyte and improve ion permeability. More preferable. On the other hand, from the viewpoint of ensuring the strength of the separator and preventing an internal short circuit, the porosity of the separator in the dried state of the separator is preferably 80% or less, and more preferably 70% or less. The porosity Po (%) of the separator is calculated by the following formula from the thickness of the separator including the height of the concave or convex pattern described above, the mass per area, and the density of the constituents:
Po={1-(m/t)/(Σa _i ·ρ _i )}×100
{In the formula, a _i is the ratio of the component i when the total mass is 1, ρ _i is the density (g/cm ³ ) of the component i, and m is the unit area of the separator. Mass (g/cm ² ) and t is the thickness (cm) of the separator. }
It can be calculated by calculating the total sum for each component i using.

The air permeability of the separator is preferably 10 seconds/100 cc or more and 500 seconds/100 cc or less, more preferably 20 seconds/100 cc or more and 450 seconds/100 cc or less, and further preferably 30 seconds/100 cc or more 450. Seconds/100 cc or less. When the air permeability is 10 seconds/100 cc or more, self-discharge tends to be further reduced when the separator is used in a non-aqueous electrolyte battery. Further, when the air permeability is 500 seconds/100 cc or less, better charge/discharge characteristics tend to be obtained.

An organic coating layer may be formed on at least one surface of the separator. That is, the separator may include an adhesive layer, if desired. The adhesive layer comprises a thermoplastic polymer. The position of the adhesive layer on the separator is not particularly limited as long as it is formed on the surface of the separator. The adhesive layer may be arranged on all of at least one surface of the separator, or may be arranged on only a part thereof. In the adhesive layer, the portion containing the thermoplastic polymer and the portion not containing the thermoplastic polymer may exist in a sea-island shape. However, it is preferable that the adhesive layer is formed on the main surface opposite to the main surface having the pattern.

[Low friction area (fine pattern)]
FIG. 1 shows an example of the configuration of the separator 10 described above, which can be wound with one surface 11 inside. In the figure, the flow direction MD of the separator 10 and the vertical direction TD perpendicular to the flow direction MD are represented by arrows. The separator 10 has at least one low-friction region 12 having a friction force of 900 gf or less, and the ratio of the area of the low-friction region 12 to the area of the one face 11 (100×area of the low-friction region 12/of the one-face 11). Area) is 0.01% or more and 10% or less.

By winding the separator 10 shown in FIG. 1 with the core material C, the separated wound body 1 is obtained. FIG. 2 shows a configuration example of a cross section that appears when the obtained separated wound body 1 is cut along the axial direction of the core material C (the radial direction of the separated wound body 1). Note that winding the separator 10 around the core material C means winding the separator 10 along the outer surface of the core material C. Therefore, theoretically, the axial center of the separation winding body 1 substantially coincides with the axial center of the core material C.

The separator winding body 1 can also be produced by winding the separator 10 (pattern region formed in the separator 10) shown in FIG. 1 as a repeating unit. Here, in the winding as the repeating unit, the separator having the pattern region formed in the separator 10 as the repeating unit (that is, the pattern region formed in the separator 10 is repeatedly arranged in the flow direction MD) Not only winding the separator 10) but also winding the separators 10 shown in FIG. 1 independent from each other a plurality of times. That is, all of the separator 10 wound around the core material C does not need to be continuous, and a part thereof may be discontinuous. When the pattern region formed on the separator 10 is wound as a repeating unit, the number of repeating is not limited, and a plurality of different repeating units may be combined. As the core material C, as will be described later, since a known material can be used, the configuration (shape, size, etc.) of the core material C shown in each drawing including FIGS. 1 and 2 is merely an example. Nothing more than.

According to the first embodiment, by winding the separator 10 so that the low friction region 12 is located at the innermost position, the low friction region 12 can be located in the region where the separator 10 and the core material C are adjacent to each other. .. Therefore, even if the number of windings is increased, the frictional force between the separator 10 and the core material C (see arrow F1 in FIG. 2) can be maintained in a relatively low range, and the low frictional area is provided. The force required to pull out the core material C (see arrow F0 in FIG. 2) can be reduced as compared with the case where it is not performed. Therefore, according to the first embodiment, it is possible to easily pull out the core material C after winding, and as a result, it is possible to prevent the deformation of the separation wound body 1 due to the pulling out of the core material C.

Moreover, according to the first embodiment, the area ratio of the low-friction region 12 is suppressed within the above range, so that in the region outside the core material C (region where the layers face each other), it is preferable that the layers are Secure friction. Therefore, even if the separator 10 has the low-friction region 12, it is possible to preferably secure the drag force (see arrow F2 in FIG. 2) that resists the pulling-out of the core material C, and this also allows the separation of the core material C by pulling-out. It is possible to prevent the revolving body 1 from being deformed.

As described below, the separator 10 can be used to form a wound product (a wound electrode body) in which a laminate of a positive electrode, a separator, and a negative electrode is wound. When the core material C is pulled out from the wound electrode body by using the separator 10 as the separator forming the innermost part of the wound electrode body (that is, the separator in contact with the outer periphery of the core material C), For the same reason, it is possible to prevent the winding-type electrode body from being deformed by pulling out the core material C.

The separator has, for example, the above-mentioned low friction region in at least one region 11a sandwiching an imaginary line VL (one-dot chain line in FIG. 1) bisecting the length L of the separator 10 in the flow direction MD on one side 11. Have twelve.
The virtual line VL is a straight line along the vertical direction TD, and divides the length L of the separator 10 in the flow direction MD into two equal parts. Of these, the length L is given by, for example, the length of a line segment that connects midpoints in the vertical direction TD of each side located at both ends in the flow direction MD of the separator 10. One side (the left side area in FIG. 1) sandwiching the virtual line VL is one area 11a, and the other side (the right side area in FIG. 1) is the other area 11b.

The low friction area 12 is provided in at least one area 11a. In the first embodiment, the low friction region 12 is unevenly distributed in the one region 11a (so that the area of the low friction region in the one region 11a is larger than the area of the low friction region in the other region 11b). The separator 10 was formed. More specifically, the low friction area 12 is provided only in one area 11a and not provided in the other area 11b. With such a configuration, it is possible to suppress the ratio of the low friction region 12 located in the region where the layers face each other. As a result, it becomes easier to suitably secure the drag force (see arrow F2 in the figure) that resists the pulling out of the core material C, and it becomes easier to prevent the deformation of the separation winding body 1 due to the pulling out of the core material C.
However, the present invention is not limited to the above example, and the low friction region 12 may be provided in both of the one region 11a and the other region 11b. At this time, the areas of the low friction regions 12 are equal in both regions. May be done. When the low-friction regions 12 are provided in both the one region 11a and the other region 11b, the low-friction regions 12 may be arranged symmetrically or asymmetrically with respect to the virtual line VL.

The upper limit of the frictional force in the low friction region 12 is preferably 870 gf or less, more preferably 850 gf or less, still more preferably 820 gf or less. When the upper limit is the above value, the core material C can be easily pulled out after winding, and as a result, the deformation of the separation wound body 1 due to the pulling out of the core material C can be easily prevented.
On the other hand, the lower limit of the frictional force of the low friction region 12 is preferably 400 gf or more, more preferably 500 gf or more, and further preferably 600 gf or more. When the lower limit is the above value, it becomes easy to ensure the minimum necessary frictional force between the separator 10 and the core material C, and thus, for example, the core material C unintentionally falls off from the separation winding body 1. It is easy to avoid that.

The low-friction region 12 is composed of a concavo-convex region (pattern region) in which a plurality of concave patterns 13 are gathered. Since the low friction region 12 is configured as the pattern region described above, when the separator 10 is wound around the core material C so that the low friction area 12 is located in the innermost area, the contact area between the separator 10 and the core material C is increased. Therefore, the frictional force between the separator 10 and the core C can be maintained in a relatively low range.
The shape, number, arrangement, etc. of the patterns 13 are not limited within the scope of the present invention. The pattern 13 may be a single pattern or a line-and-space pattern. In FIG. 1, the patterns 13 in the low-friction region 12 are regularly arranged in a grid pattern at a predetermined pitch, but the pattern layout is not limited to this example, and the pattern layout is a combination of a grid pattern and a line-and-space pattern. It may be. When a plurality of low friction regions 12 are provided on one surface 11, the pattern structure or pattern arrangement in each low friction region 12 may be the same or different.
However, the pattern 13 is preferably concave. If a convex pattern is formed, a gap is likely to be formed when wound by the height of the convex shape. Therefore, the concave pattern 13 facilitates winding the separator 10 with higher density.

The lower limit of the ratio of the area of the low friction region 12 to the area of the one surface 11 (100×area of the low friction region 12/area of the one surface 11) is preferably 0.50% or more, more preferably 1.00% or more, 2.00% or more is more preferable. By setting the lower limit to the above value, when the separator 10 is wound around the core material C so that the low friction region 12 is located in the innermost portion, the contact area between the separator 10 and the core material C is sufficiently small. Therefore, the frictional force between the separator 10 and the core material C can be sufficiently maintained in a relatively low range.
On the other hand, the upper limit of this ratio is preferably 8.0% or less, more preferably 7.0% or less, and further preferably 6.0% or less. When the upper limit is the above value, the ratio of the low friction region 2 located in the region where the layers face each other can be sufficiently suppressed.

As described above, the low friction area 12 is formed as a concave pattern area. The concave pattern 13 is not formed in a region other than the pattern region. Therefore, the area other than the pattern area is configured as the high friction area 14 having a larger frictional force than the low friction area 12. As described above, in the present embodiment, the configuration in which the high friction region 14 is located around the low friction region 12, that is, the configuration in which the low friction region 12 is sandwiched by the high friction regions 14 is realized.

In the present specification, the “friction force” is the friction force between the separator 10 and the core material C. Therefore, the frictional force of the low-friction region 12 is, for example, the separator 10 is wound around the core material C so that the low-friction region 12 is located at the innermost side to produce a separated wound body, and the separated wound body is used as a core. It is a frictional force generated when the material C is pulled out in the axial direction. The frictional force of the high-friction region 14 is, for example, a separator 10 wound around the core material C so that the high-friction region 14 is located at the innermost side to produce a separated wound body, and the separated wound body is used as a core. It is a frictional force generated when the material C is pulled out in the axial direction. As the core material C, a conventionally known core material can be preferably used as described later. The frictional force can be measured by the method described below using such a conventionally known core material C.

Here, the separator 10 has a high friction region 14 having a friction force exceeding 900 gf around the low friction region 12, and the difference between the friction force of the low friction region 12 and the friction force of the high friction region 14 is 10 gf or more. It is preferably 600 gf or less. With such a configuration, it is possible to significantly secure the difference between the frictional force in the low friction region 12 and the frictional force in the high friction region 14. Therefore, even if the number of windings increases, the core material C can be easily pulled out after winding, and the separation winding body 1 can be easily prevented from being deformed due to the pulling of the core material C.

The lower limit of the frictional force of the high friction region 14 is preferably 910 gf or more, more preferably 930 gf or more, and further preferably 940 gf or more. When the lower limit is the above value, it becomes easy to secure suitable friction between the layers in the region where the layers face each other.
On the other hand, the upper limit of the frictional force of the high friction region 14 is preferably 1000 gf or less, more preferably 970 gf or less, and further preferably 960 gf or less. When the upper limit is the above value, it becomes easy to avoid a situation in which it becomes difficult to pull out the separator 10 from the separation wound body due to the frictional force being excessively increased.

The lower limit of the difference between the frictional force of the low friction region 12 and the frictional force of the high friction region 14 is preferably 30 gf or more, more preferably 40 gf or more, and further preferably 50 gf or more. When the lower limit is in the above range, the difference between the frictional force in the low friction region 12 and the frictional force in the high friction region 14 can be significantly secured, and as a result, the effect of the present invention is easily obtained.
The upper limit of the difference between the frictional force of the low friction region 12 and the frictional force of the high friction region 14 is preferably 500 gf or less, more preferably 400 gf or less, and further preferably 300 gf or less. When the upper limit is in the above range, it is possible to avoid a situation where the frictional force of the low friction region 12 becomes excessively small or a situation where the frictional force of the high friction region 14 becomes excessively large, and as a result, according to the present invention. The effect is easily obtained.

In FIG. 1, the end of one region 11a in the flow direction MD of the separator is shown as one end 15a, and the end of the other region 11b is shown as the other end 15b.
The low-friction region 12 preferably includes an end region 16 within 10% from one end 15a of the separator 10 in the flow direction MD, based on the length L of the separator 10 in the flow direction MD. That is, a region within 0.1×L from one end portion 15a of the separator 10 along the flow direction MD is defined as an end portion region 16, and at least a part of the low friction region 12 is provided in the end portion region 16. It is preferably included.
Above all, the end region 16 is preferably within 9% from one end 15a, more preferably within 7%, and even more preferably within 5%. When the end region 16 is in the above range, the separator 10 can be easily wound around the core material C so that the low friction region 14 is located at the innermost part to produce a separate wound body.
On the other hand, the end region 16 is preferably a region of 1% or more from the one end 15a, more preferably 2% or more, and further preferably 3% or more. When the end region 16 is in the above range, the end region 16 and the low friction region 12 can easily overlap with each other, and the low friction region 12 having a sufficient area can be easily formed in the end region 16.
In particular, it is preferable that at least half of the end region 16 is included in the low friction region 12, and it is preferable that all of the end region 16 be included in the low friction region 12. From another viewpoint, it is also preferable that at least half of the low friction region 12 is included in the end region 16, and it is also preferable that all of the low friction region 12 is included in the end region 16.

FIG. 3 is a perspective view showing a configuration example when the separator 10 is wound with the one surface 11 inside. In the figure, when the separator 10 is wound around the core material C starting from one end portion 15a, the area in contact with the outer periphery of the core material C (that is, the innermost area of the separation winding body 1) is the innermost area 17 Is represented as. The low-friction region 12 preferably includes the innermost region 17 located at the innermost side when the separator 10 is wound with the one surface 11 inside. With such a configuration, when the separator 10 is wound around the core material C, the low friction region 12 can be surely positioned in the innermost portion.
In particular, it is preferable that at least half of the innermost region 17 is included in the low friction region 12, and all of the innermost region 17 is included in the low friction region 12. From another viewpoint, it is also preferable that at least half of the low friction region 12 is included in the innermost region 17, and it is also preferable that all of the low friction region 12 be included in the innermost region 17.

1 to 3, the pair of long sides of the separator 10 is along the flow direction MD, and the pair of short sides of the separator 10 is along the vertical direction TD. However, depending on the manufacturing conditions of the separator, the pair of short sides of the separator 10 may be along the vertical direction TD, and the pair of long sides of the separator 10 may be along the flow direction MD. Even in this case, the present invention is applicable. is there.

(Friction force measurement method)
First, a method of measuring the frictional force in the low friction region will be described. First, the separator to be measured is slit into a width of about 45 mm and wound. The separator is drawn out from the obtained wound body, and the core material C has a diameter of 3 mm and is divided into halves so as to pass through the center, and the central clip portion (notch portion) is sandwiched between the drawn separators. .. At this time, the low friction region is brought into contact with the outer periphery of the core material C. In addition, unnecessary parts on the free end side of the separator are cut as necessary. Then, the core C is rotated while applying a tensile force of 350 gf to the core C from the wound body side. At this time, the end side which is the free end is released and is wound into the winding by the core material C.

The core material C is continuously rotated, and when the diameter of the separation wound body reaches about 10 mm, the separator is cut and a tape is stretched around the separation wound body so that the winding is not released. Then, the separate winding body is sandwiched between the clamp members from above and below, and half of the core material C is pulled out from the separate winding body. At this time, the maximum value of the force required to pull out the core material C is measured, and this maximum value becomes the frictional force between the separator and the core material C. The measurement can be performed multiple times (for example, 5 times), and the average value thereof can be adopted as the frictional force in the low friction region. The material of the core material C is SUS304, and the surface is No. The one finished in 2B is used.

In order to measure the frictional force in the high friction area, when the clip portion (notch portion) provided in the core material C is sandwiched between the separators, only the high friction area is brought into contact with the outer periphery of the core material C, and thereafter, Can be measured in the same manner as above. Similarly, the measurement can be performed a plurality of times (for example, 5 times), and the average value thereof can be adopted as the frictional force in the high friction region.
Although the description has been given using the separate winding body here, the friction force can be measured by the same method as above when using the winding type electrode body.

[Method of manufacturing separator]
FIG. 4 is a flowchart showing an example of a separator manufacturing method according to the present embodiment (hereinafter, may be simply referred to as “manufacturing method according to the present embodiment”). The manufacturing method according to the present embodiment is a method for manufacturing a separator that is used in a non-aqueous electrolyte battery and that can be wound with one side facing inward. And a step S20 of physically forming a low friction region on the opposite side surface.

(Step S10 of preparing a base material)
Step S10 may include a step of manufacturing a base material. As a method for producing the substrate, a composition containing a polyolefin resin or the like (hereinafter, also referred to as "resin composition") and a plasticizer are melt-kneaded to form a sheet, and after stretching, if necessary, Method of making porous by extracting plasticizer; Method of making resin composition melt-kneaded and extruding at a high draw ratio, and then making it porous by peeling the resin crystal interface by heat treatment and stretching; Resin composition and inorganic A method in which a filler is melted and kneaded to form a sheet, and then the interface between the resin and the inorganic filler is peeled by stretching to make the resin porous; after the resin composition is dissolved, the resin is immersed in a poor solvent for the resin. For example, a method of making the particles porous by removing the solvent at the same time as solidifying.

When the substrate has an inorganic layer, the method for forming the inorganic layer is not particularly limited, for example, at least one surface of the microporous membrane, an inorganic layer by applying a coating liquid containing an inorganic filler and a resin binder There may be mentioned a method of forming.

The method of dispersing the inorganic filler and the resin binder in the solvent of the coating liquid is not particularly limited, for example, ball mill, bead mill, planetary ball mill, vibrating ball mill, sand mill, colloid mill, attritor, roll mill, high-speed impeller dispersion, Examples thereof include a disperser, a homogenizer, a high-speed impact mill, ultrasonic dispersion, mechanical stirring with a stirring blade and the like.

The method of applying the coating liquid to the substrate is not particularly limited, for example, gravure coater method, small diameter gravure coater method, reverse roll coater method, transfer roll coater method, kiss coater method, dip coater method, knife coater method, air The doctor coater method, the blade coater method, the rod coater method, the squeeze coater method, the cast coater method, the die coater method, the screen printing method, the spray coating method and the like can be mentioned.

The method of removing the solvent from the coating film after coating is not particularly limited as long as it does not adversely affect the microporous film, for example, a method of drying at a temperature below its melting point while fixing the microporous film or Examples include a method of drying under reduced pressure at a low temperature. From the viewpoint of controlling the shrinkage stress in the flow direction MD direction of the microporous membrane, it is preferable to appropriately adjust the drying temperature, the winding tension, and the like.

The method of applying the coating liquid to the substrate is not particularly limited, for example, gravure coater method, small diameter gravure coater method, reverse roll coater method, transfer roll coater method, kiss coater method, die coater method, screen printing method, spray A coating method, a transfer method and the like can be mentioned. More specifically, a fine pattern can be formed by coating a base material with a roll and drying.

In addition, although the example including the step of manufacturing the base material has been described in the above step S10, it is not essential to manufacture the base material in step S10. In step S10, it suffices if a base material that can be used in the next step S20 can be prepared. Therefore, the manufactured base material may be secured from another.

(Step S20 of forming a low friction area)
In the step S20 of physically forming the low friction region, the original fabric prepared in the above step S10 is used. At least one low-friction region having a friction force of 900 gf or less is physically formed on the original fabric to manufacture a separator. At this time, the low-friction region is formed so that the ratio of the area of the low-friction region to the area of one side of the original fabric is 0.01% or more and 10% or less. The low friction region can be formed, for example, in at least one region sandwiching a virtual line that bisects the length of the original fabric in the flow direction MD.

As described above, the manufacturing method according to the present embodiment physically forms the concave pattern area (low friction area). According to this, unlike the case where the frictional force of the separator is reduced by chemically treating the surface of the separator, for example, there is no possibility that the chemical substance remains. Therefore, when a non-aqueous electrolyte battery is constructed using the separator, it is possible to avoid a situation in which the battery characteristics are adversely affected by such a chemical substance.

As a method of physically forming the low-friction region, a method of using a predetermined roll (for example, a predetermined embossing roll and a predetermined elastic backup roll); a predetermined plate (for example, a predetermined embossing plate, and a predetermined plate) The method of using the elastic backup plate of No. 1) and the like can be mentioned.
In both the method using a roll and the method using a plate, a low friction region can be formed in the separator by applying a pressing force to the separator. For example, when using a roll, a low friction area|region can be formed by making a separator pass between an embossing roll and an elastic backup roll. When a plate is used, the low friction area can be formed by pressing the separator with the embossed plate and the elastic backup plate.
However, the method of physically forming the low-friction region is not limited to the above example, and for example, the forming member for applying the pressing force to the separator is not limited to the roll or the plate. The method using a roll and the method using a plate may be combined to form the low friction region.

A concave pattern area (low friction area) is formed on the separator corresponding to the unevenness of the embossing roll or the embossing plate. Therefore, by changing the concavo-convex structure of the roll or the plate, the ratio of the area of the low friction region to the area of one surface can be adjusted. The higher the density of the convex shape on the roll or plate, the higher the density of the concave pattern formed on the separator.

In addition, a concave pattern area (low friction area) is formed in the separator only while the pressing force is applied to the separator by the roll or the plate. Therefore, for example, in the case of a roll or plate that can be raised and lowered with respect to the separator, the ratio of the area of the low friction region to the area of one surface can be adjusted by adjusting the timing of raising and lowering. The longer the pressing force is applied to the separator and the more frequently the pressing force is applied to the separator, the greater the proportion of the low friction region formed in the separator.

Further, the shape of the concave pattern formed on the separator can be adjusted according to the pressing force applied to the separator by the roll or the plate, and by extension, the structure of the low friction region can be adjusted. The greater the pressing force on the separator, the wider and deeper the concave pattern formed on the separator.
Further, if the roll or the embossing is movable in the flow direction MD or the vertical direction TD, the formation position of the low friction region with respect to the separator can be adjusted.

Furthermore, when the pressing force is not applied to the separator by the roll or the plate, the higher the flow velocity of the separator, the longer the distance between the low friction regions adjacent to each other. That is, the higher the flow velocity of the separator, the longer the repeating unit of the pattern region formed in the separator.

From the above, in the step S20 of forming the low friction area, for example, before the step S25 of applying the pressing force to the separator by the roll or the plate, the step of adjusting the position of the roll or the plate (adjusting the formation position of the low friction area). Step S21), and step S22 of adjusting the pressing force applied to the separator by the roll or plate to form the low friction area, and adjusting the lifting timing of the roll or plate to adjust the formation ratio of the low friction area. It is preferable to include the step S23 of performing and the step S24 of adjusting the flow velocity of the separator.
By including such steps S21 to S24, it becomes easy to accurately form a low friction region having a desired ratio or configuration on the separator. However, each of step S21 to step S24 can be omitted, and their order is not limited to the above, and they can be appropriately replaced.

The separator may be cut at any place in step S20. The low-friction region may be formed in the separator cut into a predetermined length, while the low-friction machine may be formed in accordance with a predetermined repeating unit and then cut to produce each separator. Further, the separator may be wound again without being cut after the step S20.
The separated wound body having a low friction region in a predetermined repeating unit can be used, stored, transported, and the like in that state. Once a separation wound body having a low friction region in a predetermined repeating unit is manufactured, it is possible to save the trouble of forming the low friction region again next time, so that a desired separator can be easily provided. become.
After step S20, for example, step S30 of manufacturing a non-aqueous electrolyte battery can be performed using the obtained separator.

[Separator manufacturing equipment]
FIG. 5 is a schematic diagram showing a configuration example of a separator manufacturing apparatus (hereinafter, may be simply referred to as “manufacturing apparatus according to this embodiment”) 100 according to the present embodiment. The manufacturing apparatus 100 according to this embodiment is an apparatus for manufacturing the above separator. The manufacturing apparatus 100 physically forms at least one low-friction region having a friction force of 900 gf or less with respect to the original fabric. The low friction region can be formed, for example, in at least one region sandwiching a virtual line that bisects the length of the original fabric in the flow direction MD.

The manufacturing apparatus 100 includes a low friction area forming unit 110. The low-friction region forming unit 110 is configured to include a forming unit 120 that physically forms a low-friction region on a separator, and a control unit 200 that controls the operation of the forming unit 120.
Of these, the forming unit 120 can use a member for applying a pressing force for forming a low friction region to the separator, and for example, the roll or plate described above can be used. In FIG. 5, an embossing roll 121 and an elastic backup roll 122 are shown as the forming part 120.

The control unit 200 is mainly composed of a microcomputer, and each unit (each circuit) is realized by executing a program by the microcomputer. The control unit 200 is provided with a ROM (memory) in which various control programs or data information are stored in advance, a storage unit in which control results of each unit are stored, a timer counter for measuring various control times, and the like. ing.
Although not shown, various sensors are connected to the input side of the control unit 200. Examples of the sensors include a velocity sensor for detecting the flow velocity of the separator, a position sensor or height sensor for detecting the position or height of the forming unit 120 with respect to the separator, and a pressing force of the forming unit 120 with respect to the separator. A pressure sensor or the like for detecting

The control unit 200 performs comprehensive control for producing the separated wound body.
For example, the control unit 200 calculates the timing for moving the forming unit 120 up and down with respect to the separator based on the information input from the above sensors. In addition, the control unit 200 calculates the pressing force when the forming unit 120 is pressed against the separator based on the information input from the above sensors. Further, the control unit 200 calculates the amount of movement of the forming unit 120 in the flow direction MD or the vertical direction TD based on the information input from the above sensors. Further, the control unit 200 calculates the flow velocity of the separator based on the information input from the above sensors.
Then, the control unit 200 applies a pressing force to the separator by the forming unit 120 based on the information input from the above-mentioned sensors, the above-described calculation result, and the like, and forms the low friction region.

With the manufacturing apparatus 100 according to this embodiment, the separation wound body 1 is manufactured as follows.
First, the separator is drawn out from the wound body (separator supply unit 130) wound with the separator, and the drawn separator is connected to the core material C. The core material C is rotatably supported by the spindle unit 140, and the rotation of the core material C is controlled by the control unit 200. The core material C winds the separator.

Further, the operation of a predetermined cutting unit (not shown) is controlled by the control unit 200, and the separator is cut between the separator supply unit 130 and the spindle unit 140. The separator may be cut while the core material C is rotating, or may be cut after the rotation of the core material C is stopped.

Here, the control unit 200 controls the operation of the forming unit 120 based on the information input from the above-described sensors to form the low friction region on the separator. Particularly, in the manufacturing apparatus 100 according to the present embodiment, the low friction region is formed such that the ratio of the area of the low friction region to the area of one surface is 0.01% or more and 10% or less. As a result, the core material C can be easily pulled out from the separation wound body 1 obtained in the spindle section 140, and the separation wound body can be prevented from being deformed due to the removal of the core material C.
The control unit 200 may form the low-friction region before the separator drawn out from the separator supply unit 130 is connected to the core material C, or the low-friction region after the drawn separator is connected to the core material C. May be formed.

In the present embodiment, the pressing force applied to the separator (for example, the pressure of the separator sandwiched between the embossing roll 121 and the elastic backup roll 122) is, for example, 0.1 MPa or more and 10 MPa or less. Further, the stroke amount for moving the roll or plate up and down with respect to the separator is, for example, within 30 mm. The flow velocity of the separator is, for example, within 20 m/min.
By satisfying these conditions, the low friction region can be formed in the separator more preferably.

As described above, the separated winding body can have the separator 10 (pattern region formed on the separator 10) shown in FIG. 1 as a repeating unit.
As an application example of the first embodiment, a wound product (a wound electrode body) in which a laminate of a positive electrode, a separator 10 and a negative electrode is wound can be manufactured. In the case where the core material C is pulled out from the wound electrode body by using the separator 10 as a separator forming the innermost part of the wound electrode body (that is, a separator in contact with the outer periphery of the core material C). For the reason based on the above, it is possible to prevent the winding-type electrode body from being deformed by pulling out the core material C.

[Embodiment 2]
The second embodiment is a separate winding body. Such a separation wound body can be obtained by winding the separator having the above-mentioned low friction region with a core material. The separation wound body can also be obtained by winding the above separator (the pattern region formed on the separator) as a repeating unit.

The diameter of the core material is not particularly limited as long as it is a diameter that can be usually used, but is preferably 2 inches or more, more preferably 3 inches or more, and further preferably 6 inches or more. From the viewpoint of the productivity of the separated wound body, the diameter of the core material can be set to 10 inches or less.

The material of the core material is not particularly limited. It may include any of paper, ABS resin, polyethylene resin, polypropylene resin, polystyrene resin, polyester resin, and vinyl chloride resin. Of these, a resin is preferable and may include any of an ABS resin, a polyethylene resin, a polypropylene resin, a polystyrene resin, a polyester resin, and a vinyl chloride resin.

Although the winding length of the separator is not particularly limited, it is preferably 300 m or more, more preferably 400 m or more, and further preferably 500 m or more from the viewpoint of productivity in manufacturing a battery. The winding length of the separator may be 5000 m or less from the viewpoint of roll productivity.
Further, the cross-sectional shape of the core material is not limited, and may be any of a perfect circle shape, a flat shape, and a rectangular shape.

[Embodiment 3]
The third embodiment includes a non-aqueous electrolyte including a laminate in which the positive electrode, the separator, and the negative electrode are laminated or a wound product (a wound electrode body) obtained by winding the laminate, and a non-aqueous electrolyte. It is a battery. Examples of the form of the non-aqueous electrolyte battery include a tubular shape (for example, a rectangular tubular shape, a cylindrical shape, etc.) using a steel can, an aluminum can, or the like as an outer can. In addition, a non-aqueous electrolyte battery can be constructed by using a laminated film having a metal deposited thereon as an exterior body. A lithium-ion secondary battery is a typical example of the non-aqueous electrolyte battery.

[Positive electrode]
The positive electrode preferably includes a positive electrode active material, a conductive material, a binder, and a current collector.

｛式中、Ｍは、遷移金属元素から成る群より選ばれる少なくとも１種の元素を示し、０＜ｘ≦１．３、０．２＜ｙ＜０．８、かつ３．５＜ｚ＜４．５である。｝
で表される酸化物；
下記一般式（２）：

｛式中、Ｍは、遷移金属元素から成る群より選ばれる少なくとも１種の元素を示し、０＜ｘ≦１．３、０．８＜ｙ＜１．２、かつ１．８＜ｚ＜２．２である。｝
で表される層状酸化物；
下記一般式（３）：

｛式中、Ｍａは、遷移金属元素から成る群より選ばれる少なくとも１種の元素を示し、かつ０．２≦ｘ≦０．７である。｝
で表されるスピネル型酸化物；
下記一般式（４）：

｛式中、Ｍｃは、遷移金属元素から成る群より選ばれる少なくとも１種の元素を示す。｝で表される酸化物と下記一般式（５）：

｛式中、Ｍｄは、遷移金属元素から成る群より選ばれる少なくとも１種の元素を示す。｝で表される酸化物との複合酸化物であって、下記一般式（６）：

｛式中、Ｍｃ及びＭｄは、それぞれ上記式（４）及び（５）におけるＭｃ及びＭｄと同義であり、かつ０．１≦ｚ≦０．９である。｝
で表される、Ｌｉが過剰な層状の酸化物正極活物質；
下記一般式（７）：

｛式中、Ｍｂは、Ｍｎ、及びＣｏから成る群より選ばれる少なくとも１種の元素を示し、かつ０≦ｙ≦１．０である。｝
で表されるオリビン型正極活物質；及び
下記一般式（８）：

｛式中、Ｍｅは、遷移金属元素から成る群より選ばれる少なくとも１種の元素を示す。｝で表される化合物が挙げられる。これらの正極活物質は、１種単独で用いてもよく２種以上を併用してもよい。 As the positive electrode active material that can be contained in the positive electrode, a known material that can electrochemically store and release lithium ions can be used. Among them, a material containing lithium is preferable as the positive electrode active material. As the positive electrode active material, for example,
The following general formula (1):

{In the formula, M represents at least one element selected from the group consisting of transition metal elements, and 0<x≦1.3, 0.2<y<0.8, and 3.5<z<4 .5. }
Oxide represented by:
The following general formula (2):

{In the formula, M represents at least one element selected from the group consisting of transition metal elements, 0<x≦1.3, 0.8<y<1.2, and 1.8<z<2 .2. }
A layered oxide represented by:
The following general formula (3):

{In the formula, Ma represents at least one element selected from the group consisting of transition metal elements, and 0.2≦x≦0.7. }
A spinel oxide represented by:
The following general formula (4):

{In the formula, Mc represents at least one element selected from the group consisting of transition metal elements. } And the following general formula (5):

{In the formula, Md represents at least one element selected from the group consisting of transition metal elements. } A composite oxide with an oxide represented by the following general formula (6):

{In the formula, Mc and Md have the same meanings as Mc and Md in the above formulas (4) and (5), respectively, and 0.1≦z≦0.9. }
A layered oxide positive electrode active material having an excess of Li,
The following general formula (7):

{In the formula, Mb represents at least one element selected from the group consisting of Mn and Co, and 0≦y≦1.0. }
And an olivine-type positive electrode active material represented by the following general formula (8):

{In the formula, Me represents at least one element selected from the group consisting of transition metal elements. } The compound represented by these is mentioned. These positive electrode active materials may be used alone or in combination of two or more.

Note that a conductive material, a binder, and a current collector known in this technical field may be used to form the positive electrode.

Further, in the positive electrode mixture layer of the positive electrode, the content of the positive electrode active material is adjusted to 87% by mass to 99% by mass, the content of the conductive additive is adjusted to 0.5% by mass to 10% by mass, and/ Alternatively, the content of the binder is preferably adjusted to 0.5% by mass to 10% by mass.

[Negative electrode]
The negative electrode preferably contains a negative electrode active material, a binder, and a current collector.

As the negative electrode active material that can be included in the negative electrode, a known substance that can electrochemically store and release lithium ions can be used. The negative electrode active material is not particularly limited, but for example, carbon materials such as graphite powder, mesophase carbon fibers, and mesophase spherules; and metals, alloys, oxides, and nitrides are preferable. These may be used alone or in combination of two or more.

As the binder that can be included in the negative electrode, a known material that can bind at least two of the negative electrode active material, the conductive material that can be included in the negative electrode, and the current collector that can be included in the negative electrode can be used. The binder is not particularly limited, but for example, carboxymethyl cellulose, styrene-butadiene crosslinked rubber latex, acrylic latex, and polyvinylidene fluoride are preferable. These may be used alone or in combination of two or more.

The current collector that may be included in the negative electrode is not particularly limited, but examples thereof include metal foils such as copper, nickel, and stainless steel; expanded metal; punched metal; foam metal; carbon cloth; and carbon paper. These may be used alone or in combination of two or more.

Further, in the negative electrode mixture layer related to the negative electrode, the content of the negative electrode active material is adjusted to 88% by mass to 99% by mass, and/or the content of the binder is adjusted to 0.5% to 12% by mass. It is preferable that when the conductive additive is used, the content of the conductive additive is adjusted to 0.5% by mass to 12% by mass.

[Non-aqueous electrolyte]
As the non-aqueous electrolyte, for example, a solution (non-aqueous electrolytic solution) in which a lithium salt is dissolved in an organic solvent is used. The lithium salt is not particularly limited, and known ones can be used. Such a lithium salt is not particularly limited, but for example, LiPF ₆ (lithium hexafluorophosphate), LiClO ₄ , LiBF ₄ , LiAsF ₆ , Li ₂ SiF ₆ , LiOSO ₂ C _k F _2k+1 [formula In the formula, k is an integer of 1 to 8], LiN(SO ₂ C _k F _2k+1 ) ₂ [wherein, k is an integer of 1 to 8], LiPF _n (C _k F _2k+1 ) _6-n [In the formula, n is an integer of 1 to 5 and k is an integer of 1 to 8], LiPF ₄ (C ₂ O ₄ ), and LiPF ₂ (C ₂ O ₄ ) ₂ To be Of these, LiPF ₆ is preferable. By using LiPF ₆ , the battery characteristics and safety tend to be superior even at high temperatures. These lithium salts may be used alone or in combination of two or more.
The non-aqueous solvent used for the non-aqueous electrolyte is not particularly limited, and known ones can be used. Examples of the non-aqueous solvent include aprotic polar solvents.

The aprotic polar solvent is not particularly limited, but for example, ethylene carbonate, propylene carbonate, 1,2-butylene carbonate, 2,3-butylene carbonate, 1,2-pentylene carbonate, 2,3-pentylene carbonate. Cyclic carbonates such as trifluoromethylethylene carbonate, fluoroethylene carbonate, and 4,5-difluoroethylene carbonate; lactones such as γ-ptyrolactone and γ-valerolactone; cyclic sulfones such as sulfolane; cyclic ethers such as tetrahydrofuran and dioxane; ethyl Chain carbonates such as methyl carbonate, dimethyl carbonate, diethyl carbonate, methyl propyl carbonate, methyl isoprovir carbonate, dipropyl carbonate, methyl butyl carbonate, dibutyl carbonate, ethyl propyl carbonate, and methyl trifluoroethyl carbonate; nitriles such as acetonitrile; Examples thereof include chain ethers such as dimethyl ether; chain carboxylic acid esters such as methyl propionate; and chain ether carbonate compounds such as dimethoxyethane. These may be used alone or in combination of two or more.

The non-aqueous electrolyte may contain other additives as needed. Such additives are not particularly limited, for example, lithium salts other than those exemplified above, unsaturated bond-containing carbonates, halogen atom-containing carbonates, carboxylic acid anhydrides, sulfur atom-containing compounds (for example, sulfides, disulfides , Sulfonic acid esters, sulfites, sulfates, sulfonic anhydrides, etc.), nitrile group-containing compounds, and the like.

Specific examples of other additives are as follows:
Lithium salt: For example, lithium monofluorophosphate, lithium difluorophosphate, lithium bis(oxalato)borate, lithium difluoro(oxalato)borate, lithium tetrafluoro(oxalato)phosphate, lithium difluorobis(oxalato)phosphate, etc.;
Unsaturated bond-containing carbonate: for example, vinylene carbonate, vinyl ethylene carbonate, etc.;
Halogen atom-containing carbonate: for example, fluoroethylene carbonate, trifluoromethylethylene carbonate, etc.;
Carboxylic anhydrides: for example, acetic anhydride, benzoic anhydride, succinic anhydride, maleic anhydride, etc.;
Sulfur atom-containing compound: For example, ethylene sulfite, 1,3-propane sultone, 1,3-propene sultone, 1,4-butane sultone, ethylene sulphate, vinylene sulphate and the like;
Nitrile group-containing compound: For example, succinonitrile and the like.

When the non-aqueous electrolyte contains the other additive described above, the cycle characteristics of the battery tend to be further improved.
Among them, at least one selected from the group consisting of lithium difluorophosphate and lithium monofluorophosphate is preferable from the viewpoint of further improving the cycle characteristics of the battery. The content of at least one additive selected from the group consisting of lithium difluorophosphate and lithium monofluorophosphate is preferably 0.001% by mass or more based on 100% by mass of the non-aqueous electrolyte, and 0.1% by mass or more. 005 mass% or more is more preferable, and 0.02 mass% or more is still more preferable. When the content is 0.001% by mass or more, the cycle life of the lithium ion secondary battery tends to be further improved. Further, this content is preferably 3% by mass or less, more preferably 2% by mass or less, still more preferably 1% by mass or less. When the content is 3% by mass or less, the ionic conductivity of the lithium ion secondary battery tends to be further improved.
The content of other additives in the non-aqueous electrolyte can be confirmed by NMR measurement such as ³¹ P-NMR and ¹⁹ F-NMR.

The concentration of the lithium salt in the non-aqueous electrolyte is preferably 0.5 mol/L to 6.0 mol/L. From the viewpoint of reducing the viscosity of the non-aqueous electrolyte, the concentration of the lithium salt in the non-aqueous electrolyte is more preferably 0.9 mol/L to 1.25 mol/L. The concentration of the lithium salt in the non-aqueous electrolyte can be selected according to the purpose.
The non-aqueous electrolyte may be a liquid electrolyte or a solid electrolyte.

[Embodiment 4]
Embodiment 4 is a manufacturing apparatus and a manufacturing method of a non-aqueous electrolyte battery using the separator in which the above-mentioned low friction region is formed. In order to manufacture the non-aqueous electrolyte battery, the wound electrode body manufactured as described above may be housed in a predetermined container, and the electrolytic solution may be injected.
Here, the manufacturing method or manufacturing apparatus of the separator according to the present invention can be applied to manufacture the wound electrode body. FIG. 6 is a schematic diagram showing a configuration example of a manufacturing apparatus 600 for a nonaqueous electrolyte battery according to this embodiment. The manufacturing apparatus 600 includes the separator manufacturing apparatus 100 according to the first embodiment.

In the non-aqueous electrolyte battery manufacturing apparatus 600, the separator, the positive electrode plate, and the negative electrode plate are directed toward the core material C from their respective supply units (separator supply unit 130, positive electrode plate supply unit 300, and negative electrode plate supply unit 400). While being supplied, the core material C is rotated to wind up the separator, the positive electrode plate, and the negative electrode plate, so that the wound electrode body 500 is manufactured. The separator is wound between the electrodes so as to prevent direct contact between the positive electrode plate and the negative electrode plate. For each of the separator supply unit 130, the positive electrode plate supply unit 300, and the negative electrode plate supply unit 400, for example, a roll formed by winding a separator, a positive electrode plate, and a negative electrode plate can be used.

The separator, the positive electrode plate, the separator, and the negative electrode plate are arranged and wound in this order so that the separator 10 is located in the innermost part of the wound electrode body. Then, the low friction region is formed on the separator forming the innermost part of the wound electrode body 500. A forming part 120 (roll, plate, or the like) for applying a pressing force to the separator is arranged between the separator forming the innermost part of the wound electrode body 500 and the core material C, and the forming part 120 is formed. The operation of is controlled by the control unit 200, and a desired low friction region is formed in the separator.

In FIG. 6, an embossing roll 121 and an elastic backup roll 122 are shown as the forming portion 120, as in the example of FIG. An embossing roll 121 and an elastic backup roll 122 are arranged in a line in which the separator forming the innermost part of the wound electrode body 500 flows. Specifically, in the separator, the embossing roll 121 is arranged on the side contacting the core material C, and the elastic backup roll 122 is arranged on the side opposite to the side contacting the core material C. A low friction region is formed on the surface of the separator facing the core material C (the surface not facing the electrode), and the low friction area is in contact with the outer periphery of the core material C so that the separator, the electrode (for example, the positive electrode), The separator and the electrode (for example, the negative electrode) are wound around the core material C in this order.

As the separator supply unit 130 for forming the innermost part of the wound electrode body 500, a separator wound body (for example, the above-described separator wound body 1) in which a low friction region is formed in advance may be used. In this case, it is possible to save the labor of providing the low friction area when the wound electrode body 500 is manufactured.
On the other hand, when the wound electrode body 500 is manufactured, a low friction region may be formed with respect to the innermost separator. In this case, it becomes easy to secure straightness when pulling out the separator forming the innermost part of the wound electrode body 500.

[Other Embodiments]
Although one aspect of the present invention has been described above, the present invention is not limited to the above-described first to fourth embodiments, and addition, omission, replacement, and others of the configuration are within the scope of the gist of the present invention. Can be changed.

For example, the present invention is applicable to various power storage devices including a non-aqueous electrolyte battery typified by a lithium ion secondary battery. Further, the present invention is applicable not only to a relatively small power storage device such as a power supply for a portable electronic device, but also to a relatively large power storage device such as a power supply in a power storage field such as a residential power storage system and an electric vehicle field. Applicable. Furthermore, the separator according to the present invention can be applied to a lithium ion capacitor.

7A and 7B are views for explaining another embodiment according to the present invention.
FIG. 7A shows a long separator 10A in which the separator 10 described in FIG. 1 is used as a repeating unit (in the figure, the separator 10 is shown as a repeating unit by a dotted line). Each of the separators 10 has the low-friction region 12 formed in the above proportion, and the high-friction region 13 is arranged around the low-friction region 12. Similar to the first embodiment, the low-friction region 12 is configured as a concavo-convex region (pattern region) where concave patterns 13 are gathered. The separation wound body according to the present invention can also be obtained by winding such a long separator 10A.

As described above, the pattern may be formed only on the one surface 11, or may be formed on the surface opposite to the one surface 11. FIG. 7B shows a separator 10B in which a convex pattern 18 is formed on the surface opposite to the one surface 11 on which the low friction region 12 is formed. As described in the first embodiment, not only the separator 10 having a flat surface on the side opposite to the one surface 11 on which the concave pattern (low friction area 12) is formed, but also as shown in FIG. 7B. It should be noted that a separator having a predetermined pattern formed on the surface opposite to the one surface 11 on which the low friction region 12 is formed is also included in the scope of the present invention.

DESCRIPTION OF SYMBOLS 1 Separator winding body 10, 10A, 10B Separator 11 One side 11a One area 11b The other area 12 Low friction area 13 Pattern (concave pattern)
14 High Friction Area 15a One End 15b Other End 16 End Area 17 Innermost Area 100 Separator Manufacturing Device 110 Low Friction Area Forming Part 120 Forming Part 121 Embossing Roll 122 Elastic Backup Roll 130 Separator Supplying Part 140 Spindle Part 200 Control part 300 Positive electrode plate supply part 400 Negative electrode plate supply part 500 Winding type electrode body 600 Non-aqueous electrolyte battery manufacturing device MD Flow direction VL virtual line

Claims (12)

A separator that is used in a non-aqueous electrolyte battery and that can be wound with one side facing inward,
It has at least one low friction area where the friction force is 900 gf or less,
The ratio of the area of the low-friction region to the area of the one surface is 0.01% or more and 10% or less.
The separator according to claim 1, wherein the frictional force in the low friction region is 300 gf or more.
The separator has a high friction area around the low friction area, the friction force of which exceeds 900 gf.
The separator according to claim 1 or 2, wherein the difference between the frictional force in the low frictional region and the frictional force in the high frictional region is 10 gf or more and 600 gf or less.
The low friction region includes an end region within 10% from an end in the flow direction (MD) of the separator, based on a length in the flow direction (MD) of the separator. Item 5. The separator according to any one of items 3.
The separator according to any one of claims 1 to 4, wherein the low-friction region includes an innermost region located at the innermost side when the separator is wound with the one surface facing inward.
The separator according to any one of claims 1 to 5, wherein the low-friction region is composed of an uneven region.
A wound body obtained by winding the separator according to any one of claims 1 to 6 as a repeating unit.
A non-aqueous electrolyte containing a positive electrode, a separator according to any one of claims 1 to 6, and a laminate in which a negative electrode is laminated or a wound product obtained by winding the laminate, and a non-aqueous electrolyte. battery.
Used in a non-aqueous electrolyte battery, and a method for producing a windable separator with one side inside,
A step of preparing a raw fabric; and
At least one low-friction region having a friction force of 900 gf or less is physically formed so that the ratio of the area of the low-friction region to the area of one side of the original fabric is 0.01% or more and 10% or less. A method for manufacturing a separator, including the step of manufacturing the separator.
A method for producing a non-aqueous electrolyte battery, comprising the step of producing a non-aqueous electrolyte battery using the separator produced by the method according to claim 9.
Used in a non-aqueous electrolyte battery, and a manufacturing apparatus for manufacturing a separator that can be wound with one side inside,
At least one low-friction region having a friction force of 900 gf or less is physically formed so that the ratio of the area of the low-friction region to the area of one side of the raw fabric is 0.01% or more and 10% or less, A separator manufacturing apparatus for manufacturing the separator.
A non-aqueous electrolyte battery manufacturing apparatus, comprising the apparatus according to claim 11, and manufacturing a non-aqueous electrolyte battery using the separator.

Images