JP2017014493A - Ionic conductive film, ionic conductive composite film, and electrode complex - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ionic conductive film having high heat resistance and strength and also practical ionic conductivity and an electrode complex prepared therewith.SOLUTION: An ionic conductive film has a heat-resistant polymer and a nonaqueous electrolyte, a content of the nonaqueous electrolyte is 30-90 mass%, and the ionic conductive film is 0.3-3.0 N/μm in piercing strength.SELECTED DRAWING: None

Description

  The present invention relates to an ion conductive film, and particularly to an ion conductive film that can be suitably used as an electrolyte membrane for a battery.

  In general, in a non-aqueous electrolyte battery, in order to prevent ionic conduction between the positive and negative electrodes while preventing a short circuit due to contact between the positive and negative electrodes, a porous material having through-holes with a pore diameter of about several tens of nanometers to several micrometers A separator made of a membrane or a nonwoven fabric is used. However, when a separator having pores is used, there are problems such as dendrite (dendritic crystal) growth, short circuit due to mixed foreign matter, vulnerability to deformation such as bending and compression, and difficulty in achieving both thinning and strength maintenance. .

  As a solution to these problems, solid electrolytes can be mentioned, which are roughly classified into inorganic and organic. Further, the organic system is divided into a polymer gel electrolyte and a polymer solid electrolyte (intrinsic polymer electrolyte).

  Inorganic solid electrolytes are composed of anionic lattice points and metal ions, and many have been reported to have practical ionic conductivity (for example, Patent Document 1). They are also nonflammable, highly safe, and have a wide potential window. On the other hand, since it is an inorganic solid, brittle fracture is likely to occur and the volume change of the electrode cannot be followed, and a good interface with the electrode that is an aggregate of particles cannot be formed.

  Among organic systems, the application of a polymer gel electrolyte obtained by semi-solidifying an electrolytic solution with a polymer to a battery starts from a report of 1975 Feillelad et al. (Non-patent Document 1). Since then, various reports (for example, Patent Document 2) have been put to practical use as lithium polymer batteries for small portable devices. However, since these gel electrolytes have insufficient substantial strength in the battery, in most cases, a porous membrane is used as a reinforcing material in order to avoid contact between the positive and negative electrodes.

  On the other hand, research on polymer solid electrolytes (intrinsic polymer electrolytes) originated from Wright's paper (Non-Patent Document 2) published in 1973, and many results have been reported so far in polyether systems and the like. (For example, patent document 3). However, the ionic conductivity is still lower than that of the electrolyte system, and further improvement is required for practical use. In addition, many polymers exhibiting relatively high ionic conductivity have low elastic modulus and low heat resistance, which leads to the loss of the function of suppressing contact between the positive and negative electrodes, similar to the gel electrolyte.

  As described above, polymers having high elastic modulus, strength, and heat resistance generally have a rigid polymer structure, and thus it is considered that high ionic conductivity cannot be expected, and so far many have been studied. There wasn't.

  Films made of aromatic nitrogen-containing polymers such as aromatic polyamide (aramid) and aromatic polyimide are excellent in mechanical properties such as elastic modulus and strength and heat resistance. It is used for various purposes.

  An ion conductive film using an aromatic polyamide is disclosed in Patent Document 4, and includes a solvent-containing (or containing) in the film production process while using a rigid polymer that does not penetrate the electrolyte solution after film formation. The composite membrane of the electrolytic solution is obtained by a method of replacing the washing water) and the electrolytic solution. On the other hand, Patent Document 5 discloses a composite membrane formed by filling a polymer solid electrolyte in the voids of an aromatic polyamide porous membrane.

JP 2014-13772 A JP 2008-159596 A JP 2007-103145 A International publication WO95 / 31499 pamphlet JP-A-9-302115

G. Feillade, Ph. Perche, J. et al. Appl. Electrochem. 5, 63 (1975). P. V. Wright, Br. Polm. J. et al. , 7.319 (1975).

  However, since the heat treatment is not performed in the manufacturing method described in Patent Document 4, it is difficult to obtain a film having high dimensional stability at high temperatures. In addition, in non-aqueous electrolyte batteries such as lithium ion batteries, it is necessary to reduce the moisture content inside the battery by thorough moisture management in the components and in the assembly process. It is difficult to apply to batteries.

  Also in Patent Document 5, sufficient mechanical strength and practical ion conductivity are not obtained. Furthermore, since a porous film is used as a substrate, there is a limit to reducing the thickness.

  As described above, a film having high heat resistance and strength and practical ion conductivity has not been reported, and a separator made of a porous film or a nonwoven fabric is still used.

  In view of the above circumstances, an object of the present invention is to provide an ion conductive film and an electrode assembly that are excellent in heat resistance, strength, and ion conductivity.

  To achieve the above object, the present invention is characterized by the following configurations.

  An ion conductive film comprising a heat-resistant polymer and a non-aqueous electrolyte, wherein the content of the non-aqueous electrolyte is 30 to 90% by mass and the puncture strength is 0.3 to 3.0 N / μm.

  Since the ion conductive film of the present invention has high heat resistance and strength and practical ion conductivity, it can be suitably used as an electrolyte membrane for a battery. When the ion conductive film of the present invention is used as an electrolyte membrane for a battery, it is excellent in safety in terms of heat resistance, deformation resistance / impact, dendrite-induced short circuit, etc. Characteristics are obtained.

  The ion conductive film of the present invention is a film in which a polymer film as a base material is impregnated with a nonaqueous electrolytic solution, and the polymer film contains a heat-resistant polymer.

  Here, having ion conductivity in the present invention means that ions are passed through the membrane by having an ion permeation path in the membrane (in the case of the ion conductive film of the present invention, a free volume which is a gap between polymer molecular chains). It means that it can pass through in the thickness direction. An example of a measure of ionic conductivity is membrane resistance. The ion conductive film of the present invention preferably has a membrane resistance at 25 ° C. within the range described below. Examples of the ion species having conductivity include ions composed of metal elements belonging to Group 1 or Group 2. Specifically, lithium ions, sodium ions, potassium ions, beryllium ions, magnesium ions, calcium ions, etc. It is.

  In the present invention, the heat-resistant polymer means a polymer having a deflection temperature under load specified in JIS-K7191-2 (2007) of 100 ° C. or higher. Examples of the polymer include polyethylene terephthalate, polysulfone, polyethersulfone, polyphenylene sulfide, polyarylate, polyetherimide, polyetheretherketone, polyamide, polyimide, polyamideimide, and fluororesin. As a polymer constituting the base material of the ion conductive film of the present invention, polymers other than these heat-resistant polymers may be contained, but the ratio of these heat-resistant polymers is 40 to 100% by mass in the constituent polymers. It is preferable. Among them, it is excellent in heat resistance, and it is easy to maintain high strength when it is liquid-containing and thinned. Therefore, aromatic polyamide (including aromatic polyamic acid which is an aromatic polyimide precursor), aromatic polyimide or aromatic polyamide More preferably, imide is used as the heat resistant polymer.

The aromatic polyamide used in the present invention has a repeating unit represented by the following chemical formula (I), the aromatic polyimide has the following chemical formula (II), and the aromatic polyamideimide has a repeating unit represented by the following chemical formula (III). Preferably there is.
Chemical formula (I):

Chemical formula (II):

Chemical formula (III)

Here, Ar ₁ and Ar ₂ in the chemical formulas (I) to (III) are aromatic groups, each of which may be a single group, or a plurality of groups and a multi-component copolymer. May be. Further, the bond constituting the main chain on the aromatic ring may be either meta-orientation or para-orientation. Furthermore, a part of hydrogen atoms on the aromatic ring may be substituted with an arbitrary group.

The aromatic polyamide, aromatic polyimide, and aromatic polyamideimide used in the present invention have the chemical formula (in order to make the content of the non-aqueous electrolyte and the piercing strength in the ion conductive film of the present invention within the scope of the present invention. 25 to 100 mol% of the total of all groups of Ar ₁ and Ar ₂ in I) to (III) is from the group consisting of fluorine group, halogenated alkyl group, nitro group, cyano group, cyanate group and fluorene group An aromatic group having at least one selected group (substituent) is preferable. By having a highly electron-attracting substituent such as a fluorine group, a halogenated alkyl group, a nitro group, a cyano group, or a cyanate group, a free volume is formed between the polymer chains due to Coulomb repulsion, and a non-aqueous electrolyte solution It becomes easy to enter. It is also effective to increase the distance between polymer chains by having a bulky group such as a fluorene group. This makes it possible to contain non-aqueous electrolyte while maintaining the excellent strength and heat resistance unique to aromatic polyamides, aromatic polyimides, and aromatic polyamideimides. To do.

More preferably, 25 to 100 mol% of the total of all groups of Ar ₁ and Ar _{2 in} the chemical formulas (I) to (III) is selected from the groups represented by the following chemical formulas (IV) to (VIII): It is more preferable that the ratio is 50 to 100 mol%.
Chemical formulas (IV) to (VIII):

  Here, some of the hydrogen atoms on the aromatic rings of the chemical formulas (IV) to (VIII) are further halogen groups such as fluorine, bromine and chlorine; nitro groups; cyano groups; alkyl groups such as methyl, ethyl and propyl; It may be substituted with an arbitrary group such as an alkoxy group such as methoxy, ethoxy and propoxy, and a carboxylic acid group.

As the non-aqueous electrolyte used in the present invention, a solution obtained by dissolving an electrolyte salt in a non-aqueous solvent can be used. Examples of the electrolyte salt include a quaternary ammonium salt, a lithium salt, a sodium salt, a potassium salt, a calcium salt, and a magnesium salt. Examples of the lithium salt include LiPF ₆ , LiBF ₄ , LiClO ₄ , LiSO ₃ CF ₃ , and LiN ( _{SO 2 CF 3) 2, LiN} (SO 2 C 2 F 5) 2 and the like. Non-aqueous solvents include carbonates such as ethylene carbonate, propylene carbonate, butylene carbonate, dimethyl carbonate, diethyl carbonate, and ethyl methyl carbonate; lactones such as γ-butyrolactone and valerolactone; and acetates such as methyl acetate and ethyl acetate. , Ethers such as 1,3-dioxolane, 1,4-dioxane, tetrahydrofuran, 2-methyltetrahydrofuran, diethyl ether, 1,2-dimethoxyethane, sulfolane, acetonitrile, 1,3-dimethyl-2-imidazolidinone Usually, what mixed 2 or more types of these with various additives, such as vinylene carbonate, is used. In addition to this, an ionic liquid (room temperature molten salt) such as EMIFSA system composed of 1-ethyl-3-methylimidazolium cation and bis (fluorosulfonyl) amidoamide anion is also used. The concentration of the electrolyte salt to be dissolved is generally in the range of 0.2 to 3.0 M (mol / l). The amount of water in the non-aqueous electrolyte is preferably 0 to 300 ppm (mass basis, the same shall apply hereinafter), and more preferably 0 to 100 ppm.

  In the ion conductive film of the present invention, the content of the nonaqueous electrolytic solution in the film is 30 to 90% by mass, and preferably 40 to 80% by mass. When the content of the non-aqueous electrolyte is less than 30% by mass, the ion conductivity is low when used as an electrolyte membrane for a battery, the output characteristics of the battery are lowered, or the capacity is deteriorated when repeatedly used. May grow. When the content of the non-aqueous electrolyte exceeds 90% by mass, strength, short circuit resistance, and the like may decrease. In order to keep the content of the non-aqueous electrolyte in the ion conductive film of the present invention within the above range, a polymer having the molecular structure described above is used, and an annealing treatment described later is performed to obtain an ion conductive film. preferable.

  The thickness of the ion conductive film of the present invention is preferably 0.1 to 10 μm, and more preferably 0.1 to 5 μm. More preferably, it is 2-5 micrometers. When the thickness is less than 0.1 μm, strength, short circuit resistance, and the like may be lowered. If the thickness exceeds 10 μm, the ion conductivity is low, and when used as an electrolyte membrane for a battery, the output characteristics of the battery may decrease due to an increase in resistance, or the capacity deterioration may increase when used repeatedly. . The thickness of the ion conductive film can be controlled by the thickness of the polymer film as the base material and the content of the non-aqueous electrolyte. It can be controlled by various conditions such as material, casting thickness, heat treatment temperature and stretching conditions.

  The puncture strength of the ion conductive film of the present invention is 0.3 to 3.0 N / μm. When the puncture strength is less than 0.3 N / μm, the positive and negative electrodes may be short-circuited due to irregularities on the electrode surface, foreign matter mixed in, or deposited metal dendrites. The piercing strength is more preferably 0.8 to 3.0 N / μm, and further preferably 1.2 to 3.0 N / μm. In order to set the puncture strength within the above range, it is preferable to obtain a polymer film as a base material by using the polymer having the molecular structure described above and setting the film manufacturing method and manufacturing conditions within the ranges described below. In particular, as described later, it is preferable that the polymer film serving as a base material is a film having substantially no pores.

  The Gurley air permeability of the ion conductive film of the present invention is preferably 10,000 seconds / 100 ml or more. When the Gurley air permeability is less than 10,000 seconds / 100 ml, there are many physical through holes, and the effect of blocking penetration of metal dendrites or the like may not be obtained. Also, the strength may not fall within the scope of the present invention. In order to make the Gurley air permeability within the above range, the film production method and conditions are preferably within the range described below. In particular, it is preferable that the polymer film serving as a base material is a film having substantially no pores by setting the film production method and production conditions within the ranges described below.

The ion conductive film of the present invention preferably has a membrane resistance at 25 ° C. of 3.0 to 100.0 Ω · cm ² . More preferably, it is 3.0-50.0 ohm * cm < ² >, More preferably, it is 3.0-20.0 ohm * cm < ² >. When the membrane resistance exceeds 100.0 Ω · cm ² , when used as an electrolyte membrane for a battery, the ionic conductivity is low, the output characteristics may be lowered, or the capacity deterioration may be increased when repeatedly used. . In order to make membrane resistance into the said range, it is preferable to make content of the non-aqueous electrolyte in a film into the range of this invention.

  In the ion conductive film of the present invention, the water content in the film is preferably 0 to 1,000 ppm on a mass basis (hereinafter the same). More preferably, it is 0-500 ppm, More preferably, it is 0-300 ppm. If the moisture content in the film exceeds 1,000 ppm, characteristic deterioration may occur due to side reactions between moisture and electrolyte salts when used as an electrolyte membrane for batteries. In order to keep the water content in the film within the above range, the operation of impregnating the polymer film as a base material with a non-aqueous electrolyte is performed in a dry room or dry chamber having a dew point of −30 ° C. or lower, or an inert gas (argon It is preferable to carry out in a low humidity environment such as in a glove box filled with nitrogen.

  The ion conductive film of the present invention preferably has a 5% elongation stress (F5 value) of 50 to 1,000 MPa in the longitudinal direction (MD) and the width direction (TD). Here, MD is a film forming direction of the film (film), and TD is a direction orthogonal to the film forming direction on the film surface. When the stress at 5% elongation is less than 50 MPa, the film is not stiff when the film is thinned, and the handleability may deteriorate. Further, when used as an electrolyte membrane for a battery, the insulation between the positive and negative electrodes may not be maintained when a compressive force, bending stress, impact, or the like is applied to the battery. The 5% elongation stress is more preferably 100 to 1,000 MPa, and more preferably 200 to 1,000 MPa. In order to set the stress at 5% elongation within the above range, it is preferable to use the polymer having the above-described molecular structure and set the film production method and production conditions within the range described below. In particular, as described later, it is preferable that the polymer film serving as a base material is a film having substantially no pores.

  In the ion conductive film of the present invention, the elongation at break in the longitudinal direction (MD) and the width direction (TD) is preferably 5 to 200%. If the elongation at break is less than 5%, when used as a battery electrolyte membrane, the insulation between the positive and negative electrodes may not be maintained when compressive force, bending stress, impact, etc. are applied to the battery. . As for elongation at break, it is more preferable that all are 10-200%, and it is still more preferable that all are 20-200%. In order to make the elongation at break within the above range, it is preferable to use the polymer having the above-described molecular structure and make the film production method and production conditions within the ranges described below. In particular, as described later, it is preferable that the polymer film serving as a base material is a film having substantially no pores.

  The ion conductive film of the present invention preferably has a mechanical heat resistant temperature of 100 to 500 ° C. More preferably, it is 200-500 degreeC, More preferably, it is 300-500 degreeC. When the mechanical heat resistant temperature is less than 100 ° C., when used as an electrolyte membrane for a battery and the battery abnormally generates heat for some reason, the insulation between the positive and negative electrodes cannot be maintained and a short circuit may occur. In order to make the mechanical heat resistant temperature within the above range, it is preferable to use the polymer having the above-described molecular structure and make the film production method and production conditions within the ranges described below.

  Next, the manufacturing method of the polymer film used as the base material of the ion conductive film of this invention is demonstrated below.

  First, a method for obtaining a polymer that can be used for a polymer film serving as a base material of the ion conductive film of the present invention will be described using aromatic polyamide and aromatic polyimide as examples. Of course, the polymer that can be used in the present invention and the polymerization method thereof are not limited thereto.

  Various methods can be used to obtain the aromatic polyamide. For example, when using a low temperature solution polymerization method using acid dichloride and diamine as raw materials, N-methylpyrrolidone, N, N-dimethylacetamide, dimethylformamide And synthesized in an aprotic organic polar solvent such as dimethyl sulfoxide. In the case of solution polymerization, in order to obtain a polymer having a high molecular weight, the water content of the solvent used for the polymerization is preferably 500 ppm or less (mass basis, the same applies hereinafter), more preferably 200 ppm or less. Furthermore, a metal salt may be added for the purpose of promoting dissolution of the polymer. The metal salt is preferably an alkali metal or alkaline earth metal halide dissolved in an aprotic organic polar solvent, such as lithium chloride, lithium bromide, sodium chloride, sodium bromide, potassium chloride, potassium bromide. Etc. If both the acid dichloride and diamine used are used in equal amounts, an ultra-high molecular weight polymer may be formed. Therefore, the molar ratio should be adjusted so that one is 95.0-99.5 mol% of the other. Is preferred. In addition, the polymerization reaction of the aromatic polyamide is exothermic, but if the temperature of the polymerization system rises, side reaction may occur and the degree of polymerization may not be sufficiently increased. It is preferable to cool. Furthermore, when acid dichloride and diamine are used as raw materials, hydrogen chloride is produced as a by-product in the polymerization reaction, but when neutralizing this, an inorganic neutralizing agent such as lithium carbonate, calcium carbonate, calcium hydroxide, Alternatively, an organic neutralizer such as ethylene oxide, propylene oxide, ammonia, triethylamine, triethanolamine, diethanolamine may be used.

  On the other hand, in the case of polymerizing an aromatic polyimide that can be used in the present invention or a polyamic acid that is a precursor thereof, for example, using tetracarboxylic acid anhydride and aromatic diamine as raw materials, N-methyl-2-pyrrolidone, A method of synthesizing by solution polymerization in an aprotic organic polar solvent such as N, N-dimethylacetamide, dimethylformamide, or dimethyl sulfoxide can be employed. When equal amounts of both raw material tetracarboxylic acid anhydride and aromatic diamine are used, an ultra-high molecular weight polymer may be formed, so that the molar ratio is 90.0 to 99.5 mol% of the other. It is preferable to adjust so that. Although the polymerization reaction is accompanied by heat generation, if the temperature of the polymerization system rises, precipitation may occur due to the imidization reaction. Therefore, the temperature of the solution during polymerization is preferably 70 ° C. or less. As a method for imidizing the aromatic polyamic acid synthesized in this way to obtain an aromatic polyimide, heat treatment, chemical treatment, and a combination thereof are used. The heat treatment method is generally a method of imidizing a polyamic acid by heat treatment at about 100 to 500 ° C. On the other hand, the chemical treatment includes a method using a dehydrating agent such as an aliphatic acid anhydride and an aromatic acid anhydride using a tertiary amine such as triethylamine as a catalyst, and a method using an imidizing agent such as pyridine.

  The logarithmic viscosity (ηinh) of the aromatic polyamide and the aromatic polyimide or the polyamic acid which is a precursor thereof is preferably 1.0 to 7.0 dl / g. When the logarithmic viscosity is less than 1.0 dl / g, the bond strength between the chains due to the entanglement of the polymer molecular chains decreases, so mechanical properties such as toughness and strength may decrease, and the thermal contraction rate may increase. . When the logarithmic viscosity exceeds 7.0 dl / g, the ionic conductivity may be lowered.

  Next, a film-forming stock solution (hereinafter simply referred to as a film-forming stock solution) used in the process of producing a polymer film that is a base material of the ion conductive film of the present invention will be described.

  The polymer solution after polymerization may be used as it is for the film-forming stock solution, or it may be used after being isolated and then redissolved in an inorganic solvent such as the above-mentioned aprotic organic polar solvent or sulfuric acid. . The method for isolating the polymer is not particularly limited, but the solvent and neutralized salt are extracted into water by introducing the polymer solution after polymerization into a large amount of water, and only the precipitated polymer is separated and dried. The method etc. are mentioned. Further, a metal salt may be added as a dissolution aid during re-dissolution. The metal salt is preferably an alkali metal or alkaline earth metal halide dissolved in an aprotic organic polar solvent, such as lithium chloride, lithium bromide, sodium chloride, sodium bromide, potassium chloride, potassium bromide. Etc.

  The concentration of the polymer in the film-forming stock solution is preferably 3 to 30% by mass, more preferably 5 to 20% by mass. In order to improve the strength, heat resistance, ion conductivity, and reduction of the coefficient of static friction of the obtained ion conductive film, inorganic particles or organic particles may be added to the film forming stock solution. Examples of inorganic particles include wet and dry silica, colloidal silica, aluminum silicate, titanium oxide, calcium carbonate, calcium phosphate, barium sulfate, alumina, aluminum hydroxide, magnesium hydroxide, magnesium carbonate, zinc carbonate, titanium oxide, and zinc oxide. (Zinc flower), antimony oxide, cerium oxide, zirconium oxide, tin oxide, lanthanum oxide, magnesium oxide, barium carbonate, zinc carbonate, basic lead carbonate (lead white), barium sulfate, calcium sulfate, lead sulfate, zinc sulfide, Examples include mica, mica titanium, talc, clay, kaolin, lithium fluoride and calcium fluoride. Examples of the organic particles include particles obtained by crosslinking a polymer compound using a crosslinking agent. As such crosslinked particles, crosslinked particles of polymethoxysilane compounds, crosslinked particles of polystyrene compounds, crosslinked particles of acrylic compounds, crosslinked particles of polyurethane compounds, crosslinked particles of polyester compounds, crosslinked particles of fluorine compounds Or a mixture thereof.

  Next, a method for forming a polymer film as a base material of the ion conductive film of the present invention will be described. The film-forming stock solution prepared as described above can be formed by a so-called solution film-forming method. The solution casting method includes a dry-wet method, a dry method, a wet method, etc., and any method can be used to form a film. Here, the dry-wet method will be described as an example. In addition, the polymer film used as the base material of the ion conductive film of the present invention is formed into a laminated composite (an ion conductive composite film or an electrode composite) by directly forming a film on a substrate having holes or an electrode. Although it may form, the method of forming into a film as a single film is demonstrated here.

  In the case of forming a film by a dry-wet method, the film-forming stock solution is extruded from a die onto a support such as a drum, an endless belt, or a film to form a film-like material, and then dried until the film-like material has self-holding properties. Drying conditions can be performed, for example, in a range of 60 to 220 ° C. and within 60 minutes. However, when a polyamic acid polymer is used and it is desired to obtain a film made of polyamic acid without imidization, the drying temperature is preferably 60 to 150 ° C. More preferably, it is 60-120 degreeC. The film after the dry process is peeled off from the support and introduced into the wet process, followed by desalting and solvent removal, and further stretching, drying and heat treatment.

  Stretching is preferably within a range of 1.1 to 8.0 as a draw ratio (surface ratio is defined by a value obtained by dividing the film area after stretching by the area of the film before stretching) as a draw ratio. More preferably, it is 1.2-5.0. When the surface magnification is less than 1.1, the orientation of the polymer chain does not advance, and the strength of the ion conductive film is reduced when the non-aqueous electrolyte is contained, so that the piercing strength does not fall within the scope of the present invention. There is. If the surface magnification exceeds 8.0, the free volume inside the membrane becomes small, so the content of the nonaqueous electrolyte in the ion conductive film may not fall within the scope of the present invention.

  Moreover, as heat processing, heat processing is implemented for several seconds to several tens of minutes at the temperature of 80 to 500 degreeC, Preferably 150 to 400 degreeC. However, when using a polyamic acid polymer and obtaining a film made of polyamic acid without imidization, the heat treatment temperature is preferably 80 to 150 ° C. More preferably, it is set to 80 to 120 ° C. under reduced pressure. Generally, the higher the heat treatment temperature, the higher the heat resistance temperature of the ion conductive film, but the content of the non-aqueous electrolyte in the film decreases.

The polymer film used as the base material of the ion conductive film of the present invention obtained by the above production method has substantially no pores. Here, “having substantially no pores” means that the porosity calculated from the true specific gravity d ₀ of the constituent polymer and the bulk density d _{1 of the} membrane by (1−d ₁ / d ₀ ) × 100 is 0 to 100. It means 10%. More preferably, it is 0-5%, More preferably, it is 0-2%. Because it has virtually no pores, it has strength that is difficult to achieve with porous membranes and blocks penetration of metal dendrites, etc., so when used in battery electrolyte membranes, it is resistant to deformation even when thinned.・ Effects such as impact and short circuit caused by dendrite can be obtained. When the porosity defined above exceeds 10%, strength, short circuit resistance, and the like may deteriorate.

  The operation of impregnating the above-mentioned non-aqueous electrolyte into the polymer film, which is the base material of the ion conductive film of the present invention obtained by the above-described production method, is performed in a dry room or dry chamber having a dew point of −30 ° C. or lower, or It is preferable to carry out in a low humidity environment such as in a glove box filled with an active gas (argon, nitrogen, etc.). At this time, before the impregnation with the non-aqueous electrolyte, the polymer film serving as the base material may be subjected to surface lyophilic treatment by a known method such as corona treatment or plasma treatment.

  When the ion conductive film of the present invention is used as an electrolyte membrane for a battery, a non-aqueous electrolyte solution is injected from the injection port of the battery after the polymer film as a base material of the ion conductive film is incorporated into the battery. Alternatively, it may be impregnated with a nonaqueous electrolyte solution, or may be incorporated into a battery after impregnation with a nonaqueous electrolyte solution. In order to make the amount of water in the film within the range of the present invention, it is more preferable to impregnate by injecting a non-aqueous electrolyte after being incorporated in the battery.

  Furthermore, at this time, in order to make the content of the non-aqueous electrolyte in the ion conductive film within the scope of the present invention, in the coexistence of the polymer film serving as a base material of the non-aqueous electrolyte and the ion conductive film, 40 It is preferable to perform an annealing process at about 100 ° C. for about 10 minutes to 24 hours. By performing the annealing treatment, the non-aqueous electrolyte molecules are coordinated to the free volume portion in the polymer film as the base material, and the content of the non-aqueous electrolyte can be within the scope of the present invention. The annealing conditions are more preferably 4 to 24 hours at 50 to 80 ° C.

  The ion conductive film of the present invention may be used alone as an electrolyte membrane for a battery, or may be formed on a porous substrate and used as an ion conductive composite film. Examples of the porous substrate include polymer porous membranes and nonwoven fabrics that are generally used as battery separators. As a method of forming on the porous substrate, the porous substrate and the ion conductive film of the present invention (or the polymer film as the base material) may be laminated in order when assembling the battery. You may use what integrated the polymer film used as the base material of the ion conductive film of invention on a porous base material. Moreover, the ion conductive film of this invention is good also as an integrated electrode composite_body | complex by forming into a film by directly apply | coating on the electrode for batteries.

  Since the ion conductive film of the present invention has high heat resistance and strength and practical ion conductivity, it can be suitably used as an electrolyte membrane for a battery. When the ion conductive film of the present invention is used as an electrolyte membrane for a battery, it is excellent in safety in terms of heat resistance, deformation resistance / impact, dendrite-induced short circuit, etc. Characteristics are obtained.

  Examples of batteries to which the ion conductive film of the present invention is applied include, but are not limited to, lithium ion secondary batteries, sodium ion secondary batteries, and polyvalent ion secondary batteries such as magnesium and calcium.

  Batteries using the ion conductive film of the present invention as an electrolyte membrane include small electronic devices, transportation vehicles such as electric vehicles (EV), hybrid vehicles (HEV), plug-in hybrid vehicles (PHEV), and industrial cranes. It can be suitably used as a power source for large-scale industrial equipment. Further, it can be suitably used as a power storage device for leveling power or a smart grid in a solar cell, a wind power generator, or the like. Furthermore, it can be suitably used for a battery used in a special environment such as space.

[Methods for measuring physical properties and methods for evaluating effects]
The physical properties were measured in the examples according to the following method.

(1) Membrane resistance As a measurement electrode 1, an aluminum sheet having a thickness of 20 μm was cut into a long side of 50 mm and a short side of 40 mm. Among these, the short side 40 mm × the long side end 10 mm is a margin for connecting the tab, and the effective measurement area is 40 mm × 40 mm (1,600 mm ² = 16 cm ² ). By ultrasonically welding an aluminum tab having a width of 5 mm, a length of 30 mm, and a thickness of 100 μm at an arbitrary position on the margin of the cut aluminum sheet, the entire margin including the weld is covered with Kapton (registered trademark) tape. Insulation treatment was performed.

  As the measurement electrode 2, the same aluminum sheet as above was cut into a long side of 55 mm and a short side of 45 mm. Among these, the short side 45 mm × the long side 10 mm is a margin for connecting the tabs. By ultrasonically welding an aluminum tab having a width of 5 mm, a length of 30 mm, and a thickness of 100 μm at an arbitrary position on the margin of the cut aluminum sheet, the entire margin including the weld is covered with Kapton (registered trademark) tape. Insulation treatment was performed.

  A polymer film serving as a base material of the sample was cut out to 55 mm × 55 mm.

  The subsequent work was carried out in a dry room having a dew point of -30 ° C or lower.

  The cut measurement electrode 1, measurement electrode 2, and polymer film to be a base material were dried under reduced pressure for 12 hours in a dryer (decompression degree 0.09 MPa, 120 ° C.), and then measurement electrode 1 / polymer film / The measurement electrodes 2 were stacked in this order. At this time, all of the effective measurement area of 40 mm × 40 mm of the measurement electrode 1 was disposed so as to face the measurement electrode 2 across the sample film. Next, the above (electrode / polymer film / electrode) laminate was sandwiched between aluminum laminate films and heat-sealed leaving one side of the aluminum laminate film to form a bag.

  A laminated cell was prepared by injecting 1.5 g of a predetermined non-aqueous electrolyte into a bag-shaped aluminum laminate film and heat-sealing the short side of the aluminum laminate film while impregnating under reduced pressure. In the case of performing the annealing treatment, the produced cell was allowed to stand for 12 hours under an atmosphere of 50 ° C. as a standard condition. Two types of such cells were prepared with two or four sample films between the electrodes.

About each cell produced by the above, alternating current impedance was measured on 25 degreeC atmosphere on the conditions of voltage amplitude 10mV, frequency 10Hz-5,000kHz, and Cole-Cole plot, and calculated | required alternating current resistance ((omega | ohm)). The obtained AC resistance was plotted against the number of sample films, and the AC resistance per sample film was calculated from the slope when this plot was connected by a straight line. By multiplying the effective measurement area 16cm ² to AC resistance obtained was calculated film resistance normalized (Ω · cm ^2). The AC resistance values used for the plots described above were prepared for each of two types of evaluation cells having different numbers of sample films, and three measured values excluding the maximum and minimum AC resistance values. The average value was used.

(2) Non-aqueous electrolyte content A cell was prepared by the method described in Measurement Method (1). One sample film was taken out by cutting four sides of the aluminum laminate film of the prepared cell in a glove box under an atmosphere of argon at 23 ° C. The natural liquid was cut for 1 minute while holding one corner of the sample, and the mass (W) of the sample from which excess liquid was removed was measured.

Next, the sample was washed with an excessive amount of dimethyl carbonate to replace the non-aqueous solvent contained therein, and the electrolyte salt and additives were removed. Thereafter, the dimethyl carbonate was replaced with pure water, and dried under reduced pressure for 12 hours in a drier (decompression degree 0.09 MPa, 80 ° C.). After cooling to 23 ° C. in a dryer while reducing the pressure, the polymer film that was the base material of the sample was taken out and the mass (W ₀ ) was measured.

From the obtained W ₀ and W, the non-aqueous electrolyte content was calculated by the following formula.

Nonaqueous electrolyte content (% by mass) = ((W−W ₀ ) / W) × 100
(3) Thickness A cell was prepared by the method described in the measuring method (1). One sample film was taken out by cutting four sides of the aluminum laminate film of the prepared cell in a glove box under an atmosphere of argon at 23 ° C. A sample was obtained by removing natural liquid for 1 minute while holding one corner of the sample to remove excess liquid.

  The thickness (μm) of the sample was measured using a constant pressure thickness measuring device FFA-2 (manufactured by Ozaki Seisakusho). The probe diameter is 5 mm and the measurement load is 0.8 N or less.

(4) Puncture strength A cell was prepared by the method described in Measurement Method (1). One sample film was taken out by cutting four sides of the aluminum laminate film of the prepared cell in a glove box under an atmosphere of argon at 23 ° C. A sample was obtained by removing natural liquid for 1 minute while holding one corner of the sample to remove excess liquid.

  Using a compression tester KES-G5 (manufactured by Kato Tech Co., Ltd.), the needle entry speed was 2 mm / second, and the others were measured at 23 ° C. according to JIS-Z1707 (1997). The maximum load when the sample broke was read, and the value divided by the thickness of the sample before the test was defined as the puncture strength (N / μm).

(5) Gurley air permeability A cell was prepared by the method described in the measuring method (1). One sample film was taken out by cutting four sides of the aluminum laminate film of the prepared cell in a glove box under an atmosphere of argon at 23 ° C. A sample was obtained by removing natural liquid for 1 minute while holding one corner of the sample to remove excess liquid.

Using a B-type gale densometer (manufactured by Yasuda Seiki Seisakusho Co., Ltd.), the Gurley permeability (second / 100 ml) of the sample was measured according to the method defined in JIS-P8117 (1998). The sample is clamped in a circular hole with a diameter of 28.6 mm and an area of 642 mm ² , and the inner cylinder (inner cylinder mass 567 g) is used to pass the air in the cylinder from the test hole to the outside of the cylinder, and the time for 100 ml of air to pass is measured. By doing so, the Gurley air permeability was obtained.

  In the present invention, when the Gurley air permeability is 10,000 seconds / 100 ml or more, it is determined that there is substantially no air permeability.

(6) Water content A cell was prepared by the method described in the measuring method (1). One sample film was taken out by cutting four sides of the aluminum laminate film of the prepared cell in a glove box under an atmosphere of argon at 23 ° C. A sample was obtained by removing natural liquid for 1 minute while holding one corner of the sample to remove excess liquid.

  The amount of water in the sample was quantitatively analyzed by the water vaporization Karl Fischer method. The analysis conditions are as follows.

Apparatus: Water vaporizer VA-100 (Mitsubishi Chemical Corporation)
Moisture analyzer CA-100 (Mitsubishi Chemical Corporation)
Electrolyte: Anolyte: Coulomat AG-Oven, Catholyte: Coulomat CG
Carrier gas: Nitrogen (phosphorus pentoxide dehydration)
Sample heating temperature: 250 ± 4 ° C
Carrier gas flow rate: 200 ± 20 ml / min (7) Mechanical heat resistant temperature A cell was prepared by the method described in the measuring method (1). One sample film was taken out by cutting four sides of the aluminum laminate film of the prepared cell in a glove box under an atmosphere of argon at 23 ° C. A sample was obtained by removing natural liquid for 1 minute while holding one corner of the sample to remove excess liquid.

  Using a thermal / stress / strain measuring apparatus TMA / SS6000 and a thermal analysis rheology system EXSTAR6000 (both manufactured by Seiko Instruments Inc.), the temperature at which the film breaks or stretches by 10% is determined as the mechanical heat resistant temperature. did.

Sample size: width 4mm, length 15mm
Measurement temperature range: 25-350 ° C
Temperature increase rate: 5 ° C / min Load: 2.5Pa
Example 1
Dissolve 2,2'-ditrifluoromethyl-4,4'-diaminobiphenyl (manufactured by Toray Fine Chemical Co., Ltd.) as a diamine in dehydrated N-methyl-2-pyrrolidone (NMP, manufactured by Mitsubishi Chemical Corporation) under a nitrogen stream. And cooled to 30 ° C. or lower. Thereto, 2-chloroterephthaloyl chloride (made by Nippon Light Metal Co., Ltd.) corresponding to 99 mol% with respect to the total amount of diamine was added over 30 minutes with the system kept under 30 ° C. under a nitrogen stream. After the total amount was added, the aromatic polyamide (A) was polymerized by stirring for about 2 hours. The obtained polymerization solution was neutralized with 97 mol% of lithium carbonate (Honjo Chemical Co., Ltd.) and 6 mol% of diethanolamine (Tokyo Kasei Co., Ltd.) with respect to the total amount of the acid chloride, whereby the aromatic polyamide (A) was neutralized. A solution was obtained. The logarithmic viscosity η _inh of the obtained aromatic polyamide was 4.0 dl / g.

  The obtained aromatic polyamide solution was applied in a film form on a stainless steel (SUS316) belt as a support, dried at a hot air temperature of 120 ° C. until the film had self-supporting properties, and then the film was peeled off from the support. . Next, extraction into a water bath at 60 ° C. performed extraction of the solvent and neutralized salt. The stretching from peeling to after water bath is 1.1 times the MD of the film, and TD is not gripped. Subsequently, the obtained water-containing film is subjected to a heat treatment for 2 minutes in a tenter chamber at a temperature of 280 ° C. while being stretched at a constant length of 1.15 times to TD, and continuously wound on an MD. Thus, a polymer film serving as a base material of the ion conductive film was obtained.

A cell was produced by the method described in Measurement Method (1) using the obtained polymer film. As a non-aqueous electrolyte at this time, LiPF ₆ as an electrolyte salt dissolved in a mixed solvent of ethylene carbonate (EC) / diethyl carbonate (DEC) = 3/7 (volume ratio) to a concentration of 1 mol / L (Mitsui Chemicals) was used. The fabricated cell was annealed in an atmosphere at 50 ° C. for 12 hours, and then the membrane resistance of the ion conductive film sample was measured. Further, with respect to the cell after measuring the membrane resistance, one ion conductive film sample was taken out by cutting four sides of the aluminum laminate film in a glove box under an argon atmosphere, and each physical property was measured. The obtained evaluation results are shown in Table 1.

(Example 2)
The same as in Example 1 except that the acid chloride for obtaining the aromatic polyamide (B) is 2-fluoroterephthaloyl chloride (Ihara Nikkei Chemical Co., Ltd.) corresponding to 99 mol% with respect to the total amount of diamine. A sample was obtained. The evaluation results of the obtained samples are shown in Table 1.

(Example 3)
The diamine for obtaining the aromatic polyamide (C) is 9,9′-bis (3-methyl-4-aminophenyl) fluorene (manufactured by Wakayama Seika Kogyo Co., Ltd.), and the acid chloride is 100 mol based on the total amount of the diamine. A sample was obtained in the same manner as in Example 1 except that isophthaloyl chloride corresponding to% (Tokyo Chemical Industry Co., Ltd.) was used. The evaluation results of the obtained samples are shown in Table 1.

Example 4
4,4′-Diaminodiphenyl ether (manufactured by Tokyo Chemical Industry Co., Ltd.) as a diamine was dissolved in dehydrated NMP at room temperature. Thereto, 4,4 ′-(hexafluoroisopropylidene) diphthalic anhydride (manufactured by Tokyo Chemical Industry Co., Ltd.) corresponding to 100 mol% with respect to the total amount of diamine was added over 30 minutes. The aromatic polyamic acid (A) was polymerized by stirring for a period of time. The obtained aromatic polyamic acid had a logarithmic viscosity ηinh of 2.0 dl / g.

  The obtained aromatic polyamic acid solution was applied in a film form on a stainless steel (SUS316) plate as a support, dried in a 120 ° C. hot air oven until the film had self-supporting properties, and then the film was removed from the support. It peeled. Next, the peeled film was fixed to a metal frame, and the solvent was extracted by introducing it into a 60 ° C. water bath. Subsequently, the water-containing film taken out of the water bath is imidized by subjecting it to heat treatment for 2 minutes in a hot air oven at a temperature of 350 ° C., and becomes a base material for the ion conductive film made of the aromatic polyimide (A). A film was obtained.

  Thereafter, a sample was obtained in the same manner as in Example 1. The evaluation results of the obtained samples are shown in Table 1.

(Example 5)
In the same manner as in Example 1, a solution containing the aromatic polyamide (A) was obtained.

  Next, polyvinyl pyrrolidone (PVP) K120 (manufactured by BASF) and NMP for dilution are added to the obtained aromatic polyamide solution, and the content of the aromatic polyamide and PVP in the film forming stock solution is 8% by mass, respectively. A film-forming stock solution was prepared so as to be 8% by mass. The film-forming stock solution was stirred at 60 ° C. for 2 hours to obtain a uniform transparent solution.

  Thereafter, a sample was obtained by performing film formation and cell production in the same manner as in Example 1. The evaluation results of the obtained samples are shown in Table 1.

(Example 6)
As non-aqueous electrolyte, LiPF ₆ dissolved as an electrolyte salt in a mixed solvent of ethylene carbonate (EC) / ethyl methyl carbonate (EMC) = 1/3 (volume ratio) to a concentration of 1 mol / L (Mitsui A sample was obtained in the same manner as in Example 1 except that Chemicals) was used. The evaluation results of the obtained samples are shown in Table 1.

(Example 7)
The same procedure as in Example 1 was performed except that a non-aqueous electrolyte solution using a solution of LiPF ₆ as an electrolyte salt in a propylene carbonate (PC) solvent to a concentration of 1 mol / L (made by Mitsui Chemicals) was used. A sample was obtained. The evaluation results of the obtained samples are shown in Table 1.

(Example 8)
In the same manner as in Example 1, a solution containing the aromatic polyamide (A) was obtained. Next, alumina particles Alu C (manufactured by Nippon Aerosil Co., Ltd.) and NMP for dilution are added to the obtained aromatic polyamide solution, and the content of the aromatic polyamide and alumina particles in the film forming stock solution is 5% by mass, respectively. A film-forming stock solution was prepared so as to be 5% by mass.

  The obtained film-forming stock solution was applied in a film shape on cellulose paper MW-25 (manufactured by Miki Special Paper Co., Ltd.) having a thickness of 25 μm, and dried in a hot air oven at 120 ° C. to obtain a composite film. Next, the composite membrane was fixed to a metal frame, and the solvent was extracted by introducing it into a 60 ° C. water bath. Then, the composite film used as the base material of an ion conductive composite film was obtained by performing heat processing for 2 minutes in the hot-air oven with a temperature of 230 degreeC to the composite film of the water-containing state taken out from the water bath.

  Thereafter, in the same manner as in Example 1, a sample of an ion conductive composite film obtained by forming an ion conductive film on a porous substrate was obtained. The evaluation results of the obtained samples are shown in Table 1. The nonaqueous electrolyte content, moisture content, thickness, and piercing strength shown in Table 1 were measured by measuring a liquid-containing cellulose paper alone and an ion conductive composite film sample under the same conditions. The value of the ion conductive film layer is calculated. The Gurley air permeability and membrane resistance are reference values measured for the ion conductive composite film.

Example 9
In the same manner as in Example 1, a solution containing the aromatic polyamide (A) was obtained.

  The obtained aromatic polyamide solution was applied in the form of a film on the active material surface of a negative electrode sheet (manufactured by Hosen Co., Ltd.) using graphite having a thickness of 50 μm as an active material, and dried in a hot air oven at 80 ° C. Next, the whole of the negative electrode sheet is introduced into a 60 ° C. water bath to extract the solvent, and then subjected to a heat treatment for 15 minutes in a vacuum oven at a temperature of 80 ° C. to form a polymer serving as a base material for the ion conductive film on the negative electrode An electrode composite formed by forming a film was obtained.

  The obtained electrode composite was cut out to 55 mm × 45 mm. Among these, the short side 45 mm × 10 mm is an uncoated part for connecting the tab, and the active material application part is 45 mm × 45 mm. A copper tab having a width of 5 mm, a length of 30 mm, and a thickness of 0.1 mm was ultrasonically welded to the uncoated portion.

As a positive electrode, a positive electrode sheet (manufactured by Hosen Co., Ltd.) using lithium cobaltate (LiCoO ₂ ) having a thickness of 40 μm as an active material was cut into 50 mm × 40 mm. Among these, a short side of 40 mm × a part of the long side of 10 mm is an uncoated portion for connecting a tab, and an active material coated portion is 40 mm × 40 mm. An aluminum tab having the same size as the negative electrode tab was ultrasonically welded to the uncoated portion.

  The subsequent work was carried out in a dry room having a dew point of -30 ° C or lower.

  The cut electrode assembly and the positive electrode sheet are dried under reduced pressure for 12 hours in a dryer (decompression degree 0.09 MPa, 120 ° C.), and then the polymer film side of the electrode composite is opposed to the active material surface of the positive electrode sheet. Arranged to obtain a laminate. Next, the above laminate was sandwiched between aluminum laminate films and heat-sealed leaving one side of the aluminum laminate film to form a bag.

1.5 g of non-aqueous electrolyte solution in which LiPF ₆ as an electrolyte salt is dissolved in a mixed solvent of EC / DEC = 3/7 (volume ratio) to a concentration of 1 mol / L is injected into the bag-shaped aluminum laminate film Then, a short side portion of the aluminum laminate film was heat-sealed while being impregnated under reduced pressure to produce a laminate cell.

  The produced laminate cell was left to stand for 12 hours in an atmosphere at 50 ° C. and annealed, and then the following battery test was performed in an atmosphere at 25 ° C.

  First, constant current charging was performed at a current value of 0.5 C until 4.2 V was achieved, and constant voltage charging was performed at a voltage of 4.2 V until the current value reached 50 μA. Subsequently, constant current discharge was performed to a voltage of 2.7 V with a current value of 0.5 C. Finishing charging / discharging was implemented by performing the said charging / discharging 4 times in total so that charge and discharge may become alternate.

  About the cell which finished finish charging / discharging, constant current charge was performed until it became 4.2V with the electric current value of 0.5C. Subsequently, constant current discharge was performed up to a voltage of 2.7 V at a current value of 0.5 C to obtain a discharge capacity at 0.5 C. In 1C and 3C as well, charging was performed at a constant current of 0.5 C, and discharge capacities at respective C rates were obtained by performing constant current discharge of 1 C and 3 C. The rate of occurrence of discharge capacity at each C rate relative to the design capacity was 94% at 0.5C, 91% at 1C, and 75% at 3C, respectively.

  In addition, for the cell after the battery test, in the glove box under an argon atmosphere, the electrode composite sample was taken out by cutting four sides of the aluminum laminate film, and the non-aqueous electrolyte content of the ion conductive film layer, The moisture content, thickness, and piercing strength were measured. The evaluation results are shown in Table 1. In addition, the value shown in Table 1 is a value obtained by calculating the value of the ion conductive film layer by measuring a sample of the negative electrode sheet alone and the electrode composite under the same conditions.

(Example 10)
In the same manner as in Example 1, a solution containing the aromatic polyamide (A) was obtained. Next, alumina particles Alu C (manufactured by Nippon Aerosil Co., Ltd.) and NMP for dilution were added to the obtained aromatic polyamide solution, and the contents of the aromatic polyamide and alumina particles in the film forming stock solution were 2.5 respectively. The film-forming stock solution was prepared so that it might become mass% and 7.5 mass%.

  The obtained film-forming stock solution was applied in a film shape on a polyethylene separator F20BHE (manufactured by Toray Battery Separator Film Co., Ltd.) having a thickness of 20 μm and dried in a hot air oven at 60 ° C. to obtain a composite film. Next, the composite membrane was fixed to a metal frame, and the solvent was extracted by introducing it into a 60 ° C. water bath. Subsequently, the water-containing composite membrane taken out of the water bath was subjected to a heat treatment for 15 minutes in a vacuum oven at a temperature of 80 ° C. to obtain a composite film serving as a base material for the ion conductive composite film.

  Thereafter, in the same manner as in Example 1, a sample of an ion conductive composite film obtained by forming an ion conductive film on a porous substrate was obtained. The evaluation results of the obtained samples are shown in Table 1. The non-aqueous electrolyte content, moisture content, thickness, and puncture strength shown in Table 1 were obtained by measuring samples of a polyethylene separator alone and an ion conductive composite film in a liquid-containing state under the same conditions. The value of the ion conductive film layer is calculated. The Gurley air permeability and membrane resistance are reference values measured for the ion conductive composite film.

(Example 11)
For the fabricated cell, a sample was obtained in the same manner as in Example 1 except that the annealing treatment condition was 50 ° C./2 hours. The evaluation results of the obtained samples are shown in Table 1.

(Comparative Example 1)
Except that the diamine for obtaining the aromatic polyamide (D) is 1,3-phenylenediamine and the acid chloride is isophthaloyl chloride corresponding to 100 mol% with respect to the total amount of the diamine, the same as in Example 1. A sample was obtained. The evaluation results of the obtained samples are shown in Table 1.

(Comparative Example 2)
The diamine for obtaining the aromatic polyamide (E) is 2,2′-ditrifluoromethyl-4,4′-diaminobiphenyl corresponding to 40 mol% and 1,3 corresponding to 60 mol% with respect to the total amount of the diamine. A sample was obtained in the same manner as in Example 1 except that -phenylenediamine was used and the acid chloride was terephthaloyl chloride corresponding to 99 mol% with respect to the total amount of diamine. The evaluation results of the obtained samples are shown in Table 1.

(Comparative Example 3)
A sample was obtained in the same manner as in Example 1 except that the acid chloride for obtaining the aromatic polyamide (F) was isophthaloyl chloride corresponding to 90 mol% with respect to the total amount of the diamine. The obtained aromatic polyamide had a logarithmic viscosity η _inh of 0.9 dl / g. The evaluation results of the obtained samples are shown in Table 1.

(Comparative Example 4)
A solution containing the aromatic polyamide (G) was obtained in the same manner as in Example 1 except that 2-diamine-1,4-phenylenediamine (manufactured by Nippon Kayaku Co., Ltd.) was used as the diamine.

The obtained aromatic polyamide solution was applied in a film form on a stainless steel (SUS316) plate as a support, dried at a hot air temperature of 120 ° C. until the film had self-supporting properties, and then the film was peeled off from the support. . Next, the peeled film was fixed to a metal frame and introduced into a 60 ° C. water bath to extract the solvent and neutralized salt. Subsequently, the water-containing film taken out of the water bath was immersed in an excessive amount of non-aqueous electrolyte solution to replace the water in the film with the non-aqueous electrolyte solution, thereby obtaining a sample. Here, as the nonaqueous electrolytic solution, a solution obtained by dissolving LiPF ₆ as an electrolyte salt in a mixed solvent of EC / DEC = 3/7 (volume ratio) to a concentration of 1 mol / L was used. The evaluation results of the obtained samples are shown in Table 1.

(Comparative Example 5)
Polyvinylidene fluoride W # 7300 (manufactured by Kureha Battery Materials Japan) was dissolved in dehydrated NMP at a concentration of 10% by mass.

  The obtained PVDF solution was applied in a film shape on a stainless steel (SUS316) plate as a support, dried in a hot air oven at 120 ° C. until the film had self-supporting properties, and then the film was peeled off from the support. Next, the peeled film was fixed to a metal frame, and the solvent was extracted by introducing it into a 60 ° C. water bath. Then, the polymer film which consists of PVDF was obtained by drying the film of the moisture state taken out from the water bath for 10 minutes in 120 degreeC hot-air oven.

  Thereafter, a sample was obtained in the same manner as in Example 1. The evaluation results of the obtained samples are shown in Table 1. However, the self-supporting property of the sample taken out was low, and the piercing strength, the Gurley air permeability, and the mechanical heat resistant temperature could not be measured.

(Comparative Example 6)
A sample was obtained in the same manner as in Example 1 except that the manufactured cell was not subjected to annealing treatment at 50 ° C./12 hours (standing at 25 ° C./12 hours). The evaluation results of the obtained samples are shown in Table 1.

  Since the ion conductive film of the present invention has high heat resistance and strength and practical ion conductivity, it can be suitably used as an electrolyte membrane for a battery. When the ion conductive film of the present invention is used as an electrolyte membrane for a battery, it is excellent in safety in terms of heat resistance, deformation resistance / impact, dendrite-induced short circuit, etc. Characteristics are obtained.

Claims (6)

An ion conductive film comprising a heat-resistant polymer and a non-aqueous electrolyte, wherein the content of the non-aqueous electrolyte is 30 to 90% by mass and the puncture strength is 0.3 to 3.0 N / μm. The ion conductive film of Claim 1 whose film | membrane resistance in 25 degreeC is 3.0-100.0 ohm * cm < ² >. The ion conductive film according to claim 1, comprising an aromatic polyamide, an aromatic polyimide, or an aromatic polyamideimide as the heat resistant polymer. The ion conductive film according to any one of claims 1 to 3, wherein a moisture content in the film is 0 to 1,000 ppm on a mass basis. The ion conductive composite film formed by forming the ion conductive film in any one of Claims 1-4 on a porous base material. The electrode composite_body | complex formed by forming the ion conductive film in any one of Claims 1-4 on the electrode for batteries.