WO2010134585A1 - 多層多孔膜 - Google Patents
多層多孔膜 Download PDFInfo
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- WO2010134585A1 WO2010134585A1 PCT/JP2010/058592 JP2010058592W WO2010134585A1 WO 2010134585 A1 WO2010134585 A1 WO 2010134585A1 JP 2010058592 W JP2010058592 W JP 2010058592W WO 2010134585 A1 WO2010134585 A1 WO 2010134585A1
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- porous membrane
- porous
- multilayer
- multilayer porous
- inorganic particles
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B32—LAYERED PRODUCTS
- B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
- B32B27/00—Layered products comprising a layer of synthetic resin
- B32B27/18—Layered products comprising a layer of synthetic resin characterised by the use of special additives
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B32—LAYERED PRODUCTS
- B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
- B32B27/00—Layered products comprising a layer of synthetic resin
- B32B27/32—Layered products comprising a layer of synthetic resin comprising polyolefins
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B32—LAYERED PRODUCTS
- B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
- B32B5/00—Layered products characterised by the non- homogeneity or physical structure, i.e. comprising a fibrous, filamentary, particulate or foam layer; Layered products characterised by having a layer differing constitutionally or physically in different parts
- B32B5/22—Layered products characterised by the non- homogeneity or physical structure, i.e. comprising a fibrous, filamentary, particulate or foam layer; Layered products characterised by having a layer differing constitutionally or physically in different parts characterised by the presence of two or more layers which are next to each other and are fibrous, filamentary, formed of particles or foamed
- B32B5/32—Layered products characterised by the non- homogeneity or physical structure, i.e. comprising a fibrous, filamentary, particulate or foam layer; Layered products characterised by having a layer differing constitutionally or physically in different parts characterised by the presence of two or more layers which are next to each other and are fibrous, filamentary, formed of particles or foamed at least two layers being foamed and next to each other
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M10/00—Secondary cells; Manufacture thereof
- H01M10/42—Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells
- H01M10/4235—Safety or regulating additives or arrangements in electrodes, separators or electrolyte
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
- H01M50/40—Separators; Membranes; Diaphragms; Spacing elements inside cells
- H01M50/409—Separators, membranes or diaphragms characterised by the material
- H01M50/446—Composite material consisting of a mixture of organic and inorganic materials
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
- H01M50/40—Separators; Membranes; Diaphragms; Spacing elements inside cells
- H01M50/409—Separators, membranes or diaphragms characterised by the material
- H01M50/449—Separators, membranes or diaphragms characterised by the material having a layered structure
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
- H01M50/40—Separators; Membranes; Diaphragms; Spacing elements inside cells
- H01M50/409—Separators, membranes or diaphragms characterised by the material
- H01M50/449—Separators, membranes or diaphragms characterised by the material having a layered structure
- H01M50/451—Separators, membranes or diaphragms characterised by the material having a layered structure comprising layers of only organic material and layers containing inorganic material
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
- H01M50/40—Separators; Membranes; Diaphragms; Spacing elements inside cells
- H01M50/409—Separators, membranes or diaphragms characterised by the material
- H01M50/449—Separators, membranes or diaphragms characterised by the material having a layered structure
- H01M50/457—Separators, membranes or diaphragms characterised by the material having a layered structure comprising three or more layers
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
- H01M50/40—Separators; Membranes; Diaphragms; Spacing elements inside cells
- H01M50/489—Separators, membranes, diaphragms or spacing elements inside the cells, characterised by their physical properties, e.g. swelling degree, hydrophilicity or shut down properties
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
- H01M50/40—Separators; Membranes; Diaphragms; Spacing elements inside cells
- H01M50/489—Separators, membranes, diaphragms or spacing elements inside the cells, characterised by their physical properties, e.g. swelling degree, hydrophilicity or shut down properties
- H01M50/491—Porosity
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/10—Energy storage using batteries
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T428/00—Stock material or miscellaneous articles
- Y10T428/249921—Web or sheet containing structurally defined element or component
- Y10T428/249953—Composite having voids in a component [e.g., porous, cellular, etc.]
- Y10T428/249987—With nonvoid component of specified composition
- Y10T428/249991—Synthetic resin or natural rubbers
Definitions
- the present invention relates to a multilayer porous membrane suitably used for separation and purification of various substances and for a membrane disposed between a positive electrode and a negative electrode in a battery. Furthermore, it is related with the separator for non-aqueous electrolyte batteries using the same, and a non-aqueous electrolyte battery.
- Polyolefin porous membranes are widely used as separators in batteries and capacitors because they exhibit excellent electrical insulation and ion permeability.
- lithium ion secondary batteries with high output density and high capacity density have been used as power sources.
- Polyolefin porous membranes are mainly used in such battery separators. Is used.
- Lithium ion secondary batteries have high output density and capacity density, but because the electrolyte uses an organic solvent, the electrolyte decomposes due to heat generated by abnormal situations such as short circuit and overcharge. May cause fire.
- some safety functions are incorporated in the lithium ion secondary battery, and one of them is a separator shutdown function.
- the shutdown function is a function that stops the progress of the electrochemical reaction by suppressing the ionic conduction in the electrolytic solution by blocking the micropores of the separator due to heat melting or the like when the battery generates abnormal heat.
- the lower the shutdown temperature the higher the safety.
- polyethylene is used as a component of the separator is that it has an appropriate shutdown temperature.
- Patent Document 1 describes a technique for forming a separator by laminating a heat-resistant layer on a first porous layer mainly composed of a thermoplastic resin. .
- Patent Document 1 the separator described in Patent Document 1 is considered to be improved in safety as compared with a normal separator having no heat-resistant layer, it suppresses the thermal contraction of the separator even in a high temperature environment, and the separator breaks the membrane. From the viewpoint of reducing the risk of short circuiting, there is still room for improvement. Further, depending on the inorganic particles used, an increase in the weight of the inorganic particle-containing layer itself cannot be ignored. In particular, since the amount of separators used in large-sized batteries for in-vehicle applications increases dramatically, the effect tends to increase.
- the inventors of the present invention have made heat-shrinkage at a high temperature by using inorganic particles mainly composed of an aluminum silicate compound in a polyolefin porous film in which an inorganic particle-containing layer is laminated. It has been found that a multilayer porous membrane with suppressed can be realized.
- the inorganic particle layer is composed of particles containing calcined kaolin as a main component, so that it is very lightweight and the heat shrinkage rate at high temperature is suppressed. It has been found that a multilayer porous membrane can be realized.
- the inorganic particle layer is composed of particles mainly composed of wax stone clay, making it extremely lightweight and heat resistant even with very thin inorganic particle layer thicknesses.
- the present inventors have found that the heat shrinkage rate at a high temperature is remarkably suppressed and a short-circuit does not occur even at a high temperature of 200 ° C. or higher while having a good shutdown function.
- a multilayer porous membrane comprising a porous layer containing inorganic particles and a resinous binder on at least one surface of a porous membrane containing a polyolefin resin as a main component, wherein the inorganic particles contain an aluminum silicate compound as a main component.
- the aluminum silicate compound is calcined kaolin.
- the resinous binder is polyvinyl alcohol.
- the multilayer porous membrane according to the above [11] wherein the ratio of polypropylene to the total polyolefin in the resin composition is 1 to 35% by mass.
- a separator for a non-aqueous electrolyte battery comprising the multilayer porous membrane according to any one of [1] to [12].
- a nonaqueous electrolyte battery comprising the separator for a nonaqueous electrolyte battery according to the above [13], a positive electrode, a negative electrode, and an electrolytic solution.
- the present invention it is possible to provide a multilayer porous membrane in which thermal shrinkage is suppressed even under a high temperature environment, a separator for a nonaqueous electrolyte battery and a nonaqueous electrolyte battery using the multilayer porous membrane.
- 3 is an X-ray diffraction pattern of calcined kaolin 1 used in Example 3-1.
- 3 is an X-ray diffraction pattern of calcined kaolin 1 used in Example 3-2.
- 3 is an X-ray diffraction pattern of kaolin 1 used in Example 3-3.
- 4 is an X-ray diffraction pattern of kaolin 2 used in Example 3-4. It is an X-ray diffraction pattern of the synthetic aluminum silicate used in Example 3-5.
- FIG. 4 is an X-ray diffraction pattern of a waxy clay used in Example 4-1. It is an X-ray diffraction pattern of Kaolin 1 used in Example 4-2.
- FIG. 4 is an X-ray diffraction pattern of kaolin 2 used in Example 4-3.
- FIG. It is an X-ray diffraction pattern of the synthetic aluminum silicate used in Example 4-4.
- the present embodiment a mode for carrying out the present invention (hereinafter abbreviated as “the present embodiment”) will be described in detail.
- this invention is not limited to the following embodiment, It can implement by changing variously within the range of the summary.
- the multilayer porous layer according to the first embodiment of the present invention comprises a porous layer containing inorganic particles and a resinous binder on at least one surface of a porous film mainly composed of a polyolefin resin, and the inorganic particles are made of aluminum silicate. Contains a compound as the main component.
- the multilayer porous layer according to the second embodiment of the present invention includes a porous film mainly composed of a polyolefin resin, inorganic particles mainly composed of calcined kaolin and a resinous binder laminated on at least one surface of the porous film. It has a porous layer containing.
- the multilayer porous layer according to the third embodiment of the present invention includes a porous film mainly composed of a polyolefin resin, inorganic particles mainly composed of a waxy clay and a resinous binder laminated on at least one surface of the porous film. And a porous layer.
- the inorganic particles containing an aluminum silicate compound as a main component are inorganic particles in which the aluminum silicate compound occupies 50% or more and 100% or less of the mass fraction of the entire inorganic particles.
- the proportion of the aluminum silicate compound is more preferably 70% or more and 100% or less, and further preferably 80% or more and 100% or less.
- the ratio of the particles having a particle size of 0.2 ⁇ m to 1.4 ⁇ m to the entire inorganic particles is preferably 2% by volume or more, more preferably 3% by volume or more, and further preferably 5% by volume. % Or more, preferably 90% by volume or less, more preferably 80% by volume or less.
- the porous layer may be laminated only on one side of the porous film or on both sides.
- the proportion of the particles having a particle size larger than 0.2 ⁇ m and not larger than 1.0 ⁇ m in the entire inorganic particles is preferably 1% by volume or more, more preferably 2% by volume or more, preferably 80%. Volume% or less, More preferably, it is 70 volume% or less.
- the proportion of the particles having a particle size larger than 0.5 ⁇ m and not larger than 2.0 ⁇ m in the entire inorganic particles is preferably 8% by volume or more, more preferably 10% or more, preferably It is 60 volume% or less, More preferably, it is 50 volume% or less.
- the proportion of the particles having a particle size larger than 0.6 ⁇ m and smaller than 1.4 ⁇ m in the whole inorganic particles is preferably 1% by volume or more, more preferably 3% by volume or more, preferably Is 40% by volume or less, more preferably 30% by volume or less.
- Such a ratio is preferable from the viewpoint of suppressing thermal contraction of the porous film at a high temperature even when the thickness of the porous layer is thinner and realizing better heat resistance.
- a method for adjusting the ratio of the particle size a method of pulverizing inorganic particles using a ball mill, a bead mill, a jet mill or the like to reduce the particle size can be exemplified.
- the average particle size of the inorganic particles is preferably 0.1 ⁇ m to 15 ⁇ m, more preferably 0.1 ⁇ m to 5 ⁇ m, still more preferably greater than 0.1 ⁇ m to 4.0 ⁇ m or less, and even more preferably greater than 0.14 ⁇ m. .9 ⁇ m or less, particularly preferably more than 0.14 ⁇ m and 3.0 ⁇ m or less.
- the porous layer may be laminated only on one side of the porous film or on both sides.
- Natural products include, for example, kaolinite, dickite, nacrite, halloysite, pyrophyllite, audinite, montmorillonite, beidellite, nontronite, bolcon scoreite, saponite, sauconite, swinholderite, vermiculite, verchelin, amesite , Keriaite, fraponite, brindriaite, biotite, phlogopite, iron mica, east knight, siderophyllite tetraferri iron mica, scale mica, polylithionite, muscovite, celadonite, iron ceradonite, iron alumino ceradon Stone, alumino seradone stone, tobe mica, soda mica, clintonite, kinoshita, bite mica agate, ananda stone, pearl mica, clinochlore, chamosite, penantite,
- Aluminosilicate minerals that do not have ion exchange capacity such as kaolinite, dickite, nacrite, halloysite, and pyrophyllite are preferred because they are less likely to inhibit lithium ion migration, and are also electrochemically stable.
- Kaolins mainly composed of kaolin minerals such as kaolinite and wax stones mainly composed of pyrophyllite can be preferably used because they are inexpensive and easily available.
- Kaolin includes wet kaolin and calcined kaolin obtained by calcining this, and any of them can be preferably used.
- the calcined kaolin is particularly preferable in terms of electrochemical stability because impurities are removed in addition to the release of crystal water during the calcining treatment.
- a very lightweight porous layer can be realized while maintaining high permeability.
- thermal contraction of the porous film at a high temperature is suppressed, and excellent heat resistance tends to be exhibited.
- calcined kaolin among the inorganic particles, it is possible to realize a separator that is excellent in light weight and has a suppressed rate of increase in air permeability.
- the porous layer may be laminated only on one side of the porous film or on both sides.
- Calcinated kaolin is obtained by calcining a kaolin mainly composed of kaolin minerals such as kaolinite or a pyroxene composed mainly of pyrophyllite. In addition to releasing crystal water during the firing treatment, impurities are removed, which is preferable in terms of chemical stability in the battery, particularly electrochemical stability, compared to kaolin and the like.
- the average particle size of the calcined kaolin is preferably greater than 0.1 ⁇ m and not greater than 4.0 ⁇ m, more preferably greater than 0.2 ⁇ m and not greater than 3.5 ⁇ m, and greater than 0.4 ⁇ m and not greater than 3.0 ⁇ m. It is particularly preferred. Such an average particle diameter is preferable from the viewpoint of suppressing thermal shrinkage at high temperatures even when the porous layer is thin (for example, 7 ⁇ m or less).
- a very lightweight porous layer can be realized while maintaining high permeability by adopting particles composed mainly of wax stone clay as inorganic particles constituting the porous layer. Furthermore, even at a thinner porous layer thickness, thermal contraction of the porous film at a high temperature is suppressed, and excellent heat resistance tends to be exhibited.
- the porous layer may be laminated only on one side of the porous film or on both sides.
- the average particle size of the particles mainly composed of waxy clay is preferably larger than 0.1 ⁇ m and not larger than 4.0 ⁇ m, and larger than 0.2 ⁇ m and not larger than 3.5 ⁇ m. More preferably, it is more preferably 0.4 ⁇ m to 3.0 ⁇ m. Such an average particle diameter is preferable from the viewpoint of suppressing thermal shrinkage at high temperatures even when the porous layer is thin (for example, 7 ⁇ m or less).
- the resin binder includes a resinous binder for binding the inorganic particles onto the porous film.
- a resinous binder for binding the inorganic particles onto the porous film.
- the type of resinous binder but when the multilayer porous membrane of the present embodiment is used as a separator for a lithium ion secondary battery, it is insoluble in the electrolyte solution of the lithium ion secondary battery, and It is preferable to use one that is electrochemically stable within the range of use of the lithium ion secondary battery.
- Such a resinous binder include, for example, polyolefins such as polyethylene and polypropylene; fluorine-containing resins such as polyvinylidene fluoride and polytetrafluoroethylene; vinylidene fluoride-hexafluoropropylene-tetrafluoroethylene copolymer; Fluorine-containing rubber such as ethylene-tetrafluoroethylene copolymer; styrene-butadiene copolymer and its hydride, acrylonitrile-butadiene copolymer and its hydride, acrylonitrile-butadiene-styrene copolymer and its hydride, methacryl Acid ester-acrylic acid ester copolymer, styrene-acrylic acid ester copolymer, acrylonitrile-acrylic acid ester copolymer, ethylene propylene rubber, polyvinyl alcohol, polyvinyl acetate, etc.
- Class Cellulose derivatives such as ethyl cellulose, methyl cellulose, hydroxyethyl cellulose, carboxymethyl cellulose; melting point and / or glass transition temperature of polyphenylene ether, polysulfone, polyether sulfone, polyphenylene sulfide, polyetherimide, polyamideimide, polyamide, polyester, etc.
- the above resin etc. are mentioned.
- the saponification degree is preferably 85% or more and 100% or less.
- the saponification degree is 85% or more, when the multilayer porous membrane is used as a battery separator, the temperature at which a short circuit (short temperature) is improved and good safety performance tends to be obtained, which is preferable.
- the saponification degree is more preferably 90% or more and 100% or less, further preferably 95% or more and 100% or less, and particularly preferably 99% or more and 100% or less.
- the polymerization degree of polyvinyl alcohol is preferably 200 or more and 5000 or less, more preferably 300 or more and 4000 or less, and particularly preferably 500 or more and 3500 or less.
- the degree of polymerization is 200 or more, particles containing an aluminum silicate compound as a main component can be firmly bound with a small amount of polyvinyl alcohol, and the multi-layer porous membrane can be formed by forming a porous layer while maintaining the mechanical strength of the porous layer. This is preferable because it tends to suppress an increase in the temper.
- it exists in the tendency which can prevent the gelatinization at the time of preparing a coating liquid as a polymerization degree is 5000 or less, it is preferable.
- the proportion (% by mass) of the inorganic particles in the porous layer is 50% or more and less than 100% from the viewpoint of the binding properties of the inorganic particles, the permeability and heat resistance of the multilayer porous membrane, and the like. Preferably, it is 70% or more and 99.99% or less, more preferably 90% or more and 99.9% or less, and particularly preferably 95% or more and 99% or less.
- the layer thickness of the porous layer is preferably 1 ⁇ m or more from the viewpoint of the heat resistance of the multilayer porous membrane, and preferably 50 ⁇ m or less from the viewpoint of increasing the capacity and permeability of the battery. More preferably, they are 1.5 micrometers or more and 10 micrometers or less, More preferably, they are 2 micrometers or more and 7 micrometers or less, Especially preferably, they are 3 micrometers or more and 7 micrometers or less.
- a porous layer using calcined kaolin as inorganic particles exhibits excellent heat resistance even when the density of the porous layer is small compared to a porous layer made of inorganic particles having the same specific gravity.
- a permeable multilayer porous membrane can be realized.
- the layer density of the formed porous layer is preferably 0.6 to 1.2 cm 3 , more preferably 0.6 to 1.1 cm 3 , and 0.7 to 1.1 cm 3. Particularly preferred.
- Porous layers using wax stone clay as inorganic particles are very lightweight because they exhibit excellent heat resistance even when the density of the porous layer is small compared to porous layers made of inorganic particles having the same specific gravity.
- a highly permeable multilayer porous membrane can be realized.
- the layer density of the formed porous layer is preferably 0.5 to 1.1 cm 3 , more preferably 0.6 to 1.0 cm 3 , and preferably 0.7 to 0.95 cm 3. Particularly preferred.
- Examples of the method for forming a porous layer include a method in which a porous layer is formed by applying a coating solution containing inorganic particles and a resinous binder to at least one surface of a porous film mainly composed of a polyolefin resin. .
- the solvent for the coating solution is preferably one that can uniformly and stably disperse or dissolve the inorganic particles and the resinous binder.
- N-methylpyrrolidone, N, N-dimethylformamide, N, N-dimethylacetamide, Water, ethanol, toluene, hot xylene, methylene chloride, hexane and the like can be mentioned.
- additives such as surfactants, thickeners, wetting agents, antifoaming agents, PH preparations containing acids and alkalis are added to the coating solution in order to stabilize dispersion and improve coating properties. May be added.
- These additives are preferably those that can be removed when the solvent is removed, but are electrochemically stable in the range of use of the lithium ion secondary battery, do not inhibit the battery reaction, and are stable up to about 200 ° C. If present, it may remain in the porous layer.
- the method for dissolving or dispersing the inorganic particles and the resinous binder in the solvent of the coating solution is not particularly limited as long as it can achieve the dissolution or dispersion characteristics of the coating solution necessary for the coating step.
- examples thereof include a ball mill, a bead mill, a planetary ball mill, a vibrating ball mill, a sand mill, a colloid mill, an attritor, a roll mill, a high-speed impeller dispersion, a disperser, a homogenizer, a high-speed impact mill, ultrasonic dispersion, and mechanical stirring using a stirring blade.
- the method for applying the coating solution to the porous film is not particularly limited as long as it can achieve the required layer thickness and coating area.
- 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 doctor coater method, blade coater method, rod coater method, squeeze coater method, cast Examples include a coater method, a die coater method, a screen printing method, and a spray coating method.
- the surface treatment method is not particularly limited as long as it does not significantly impair the porous structure of the porous film.
- corona discharge treatment method mechanical surface roughening method, solvent treatment method, acid treatment method, ultraviolet oxidation method Etc.
- the method for removing the solvent from the coating film after coating is not particularly limited as long as it does not adversely affect the porous film.
- a method of drying at a temperature below the melting point while fixing the porous film a method of drying under reduced pressure at a low temperature, a method of immersing in a poor solvent for the resinous binder to solidify the resinous binder and extracting the solvent at the same time, etc. Is mentioned.
- a porous membrane mainly composed of a polyolefin resin is a polyolefin in which the polyolefin resin occupies 50% or more and 100% or less of the mass fraction of the resin component constituting the porous membrane from the viewpoint of shutdown performance when used as a battery separator.
- a porous film made of a resin composition is preferred.
- the proportion of the polyolefin resin is more preferably 60% or more and 100% or less, and still more preferably 70% or more and 100% or less.
- the polyolefin resin is a polyolefin resin used for normal extrusion, injection, inflation, blow molding, etc., such as ethylene, propylene, 1-butene, 4-methyl-1-pentene, 1-hexene, 1-octene, etc. Homopolymers and copolymers, multistage polymers, and the like can be used. In addition, polyolefins selected from the group consisting of these homopolymers, copolymers, and multistage polymers can be used alone or in combination.
- polystyrene resin examples include low density polyethylene, linear low density polyethylene, medium density polyethylene, high density polyethylene, ultrahigh molecular weight polyethylene, isotactic polypropylene, atactic polypropylene, ethylene-propylene random copolymer, polybutene. And ethylene propylene rubber.
- the multilayer porous membrane When the multilayer porous membrane is used as a battery separator, it is particularly preferable to use a resin mainly composed of high-density polyethylene because of its low melting point and high strength. From the viewpoint of improving the heat resistance of the porous film and the heat resistance of the multilayer porous film, it is more preferable to use a porous film made of polypropylene and a resin composition containing a polyolefin resin other than polypropylene.
- the three-dimensional structure of polypropylene is not limited, and any of isotactic polypropylene, syndiotactic polypropylene, and atactic polypropylene may be used.
- the ratio of polypropylene to the total polyolefin in the polyolefin resin composition is preferably 1 to 35% by mass, more preferably 3 to 20% by mass, and still more preferably from the viewpoint of achieving both heat resistance and a good shutdown function. 4 to 10% by mass.
- the polyolefin resin other than polypropylene is not limited, and examples thereof include homopolymers or copolymers of olefin hydrocarbons such as ethylene, 1-butene, 4-methyl-1-pentene, 1-hexene, and 1-octene. Can be mentioned. Specific examples include polyethylene, polybutene, and ethylene-propylene random copolymer.
- the polyolefin resin other than polypropylene is low density polyethylene, linear low density polyethylene, medium It is preferable to use polyethylene such as density polyethylene, high density polyethylene, and ultrahigh molecular weight polyethylene. Among these, from the viewpoint of strength, it is more preferable to use polyethylene having a density measured according to JIS K 7112 of 0.93 g / cm 3 or more.
- the viscosity average molecular weight of the polyolefin resin is preferably from 30,000 to 12 million, more preferably from 50,000 to less than 2 million, and even more preferably from 100,000 to less than 1 million.
- a viscosity average molecular weight of 30,000 or more is preferable because the melt tension during melt molding increases, moldability is improved, and the strength tends to increase due to entanglement between polymers.
- a viscosity average molecular weight of 12 million or less is preferable because uniform melt kneading is facilitated and the formability of the sheet, particularly thickness stability, tends to be excellent.
- the viscosity average molecular weight is less than 1,000,000 because it tends to close a hole when the temperature rises and a good shutdown function tends to be obtained.
- a polyolefin having a viscosity average molecular weight of less than 1 million instead of using a polyolefin having a viscosity average molecular weight of less than 1 million alone, a mixture of a polyolefin having a viscosity average molecular weight of 2 million and a polyolefin having a viscosity average molecular weight of 270,000, the viscosity average molecular weight being less than 1 million Mixtures may be used.
- Arbitrary additives can be contained in the polyolefin resin composition.
- additives include polymers other than polyolefins; inorganic particles; antioxidants such as phenolic, phosphorous, and sulfur; metal soaps such as calcium stearate and zinc stearate; ultraviolet absorbers; Stabilizers; antistatic agents; antifogging agents; colored pigments and the like.
- the total addition amount of these additives is preferably 20 parts by mass or less, more preferably 10 parts by mass or less, and still more preferably 5 parts by mass or less with respect to 100 parts by mass of the polyolefin resin composition.
- the average pore diameter of the porous membrane there is no limitation on the average pore diameter of the porous membrane, and it can be determined appropriately according to the application. However, when the multilayer porous membrane is used as a battery separator, the average pore size is preferably 0.001 ⁇ m to 10 ⁇ m, more preferably 0.01 ⁇ m to 1 ⁇ m.
- the method for producing the porous film is not limited, and a known production method can be employed.
- the polyolefin crystal interface is peeled off by heat treatment and stretching, the polyolefin resin composition and the inorganic filler are melt-kneaded and molded on a sheet, and then the polyolefin and inorganic filler are stretched And a method of making the structure porous by removing the solvent at the same time as solidifying the polyolefin by dissolving it in a poor solvent for the polyolefin after dissolving the polyolefin resin composition.
- a method for extracting a plasticizer after melting and kneading a polyolefin resin composition and a plasticizer to form a sheet will be described.
- a polyolefin resin composition and a plasticizer are melt-kneaded.
- a resin kneading apparatus such as an extruder, kneader, lab plast mill, kneading roll, Banbury mixer, etc.
- the polyolefin resin, other additives, and the plasticizer are pre-kneaded in advance at a predetermined ratio using a Henschel mixer or the like before being added to the resin kneading apparatus. More preferably, only a part of the plasticizer is added in the pre-kneading, and the remaining plasticizer is kneaded while side-feeding the resin kneading apparatus. By doing so, the dispersibility of the plasticizer is increased, and when stretching a sheet-like molded product of the melt-kneaded mixture of the resin composition and the plasticizer in the subsequent step, the film is stretched at a high magnification without breaking. can do.
- a non-volatile solvent capable of forming a uniform solution above the melting point of the polyolefin
- a non-volatile solvent include hydrocarbons such as liquid paraffin and paraffin wax; esters such as dioctyl phthalate and dibutyl phthalate; higher alcohols such as oleyl alcohol and stearyl alcohol.
- liquid paraffin has high compatibility with polyethylene and polypropylene, and even when the melt-kneaded product is stretched, the interface peeling between the resin and the plasticizer does not easily occur. Therefore, uniform stretching tends to be easily performed. Therefore, it is preferable.
- the ratio of the polyolefin resin composition and the plasticizer is not particularly limited as long as they can be uniformly melt-kneaded and formed into a sheet shape.
- the mass fraction of the plasticizer in the composition comprising the polyolefin resin composition and the plasticizer is preferably 30 to 80 mass%, more preferably 40 to 70 mass%.
- the mass fraction of the plasticizer is 80% by mass or less, the melt tension at the time of melt molding is hardly insufficient and the moldability tends to be improved.
- the mass fraction is 30% by mass or more, even if the mixture of the polyolefin resin composition and the plasticizer is stretched at a high magnification, the polyolefin chain is not broken, and a uniform and fine pore structure is formed and the strength is also improved. Easy to increase.
- melt-kneaded product is formed into a sheet.
- a melt-kneaded product is extruded into a sheet shape via a T-die or the like, and brought into contact with a heat conductor to cool to a temperature sufficiently lower than the crystallization temperature of the resin component. And then solidify.
- a heat conductor used for cooling and solidification metal, water, air, plasticizer itself, or the like can be used. However, a metal roll is preferable because of high heat conduction efficiency.
- the die lip interval when extruding into a sheet form from a T die is preferably 400 ⁇ m or more and 3000 ⁇ m or less, and more preferably 500 ⁇ m or more and 2500 ⁇ m or less.
- the die lip interval is 400 ⁇ m or more, the mess and the like are reduced, and there is little influence on the film quality such as streaks and defects, and there is a tendency that film breakage and the like can be prevented in the subsequent stretching step.
- the die lip interval is 3000 ⁇ m or less, the cooling rate is high and uneven cooling can be prevented and the thickness stability of the sheet tends to be maintained.
- the sheet-like molded body it is preferable to stretch the sheet-like molded body thus obtained.
- the stretching treatment either uniaxial stretching or biaxial stretching can be suitably used, but biaxial stretching is preferred from the viewpoint of the strength of the porous film to be obtained.
- the sheet-like molded body is stretched at a high magnification in the biaxial direction, the molecules are oriented in the plane direction, and the finally obtained porous film is difficult to tear and has high puncture strength.
- the stretching method include simultaneous biaxial stretching, sequential biaxial stretching, multi-stage stretching, multiple stretching, and the like, and simultaneous biaxial from the viewpoint of improvement of puncture strength, uniformity of stretching, and shutdown property Stretching is preferred.
- simultaneous biaxial stretching means stretching in which stretching in the MD direction (machine direction of the microporous membrane) and stretching in the TD direction (direction crossing the MD of the microporous membrane at an angle of 90 °) are performed simultaneously. It refers to a method, and the draw ratio in each direction may be different.
- Sequential biaxial stretching refers to a stretching method in which stretching in the MD direction or TD direction is performed independently. When stretching is performed in the MD direction or TD direction, the other direction is unconstrained or constant length. It is assumed that it is fixed to
- the draw ratio is preferably in the range of 20 times to 100 times in terms of surface magnification, and more preferably in the range of 25 times to 50 times.
- the stretching ratio in each axial direction is preferably in the range of 4 to 10 times in the MD direction, preferably in the range of 4 to 10 times in the TD direction, 5 to 8 times in the MD direction, and 5 times in the TD direction. More preferably, it is in the range of 8 times or less.
- the sheet-like molded body may be rolled.
- Rolling can be performed, for example, by a pressing method using a double belt press or the like.
- Rolling can particularly increase the orientation of the surface layer portion.
- the rolling surface magnification is preferably greater than 1 and 3 or less, more preferably greater than 1 and 2 or less.
- the rolling ratio is larger than 1, the plane orientation increases and the film strength of the finally obtained porous film tends to increase.
- a rolling ratio of 3 or less is preferable because the orientation difference between the surface layer portion and the center is small and a uniform porous structure tends to be formed in the thickness direction of the film.
- the plasticizer is removed from the sheet-like molded body to form a porous film.
- a method for removing the plasticizer for example, a method of extracting the plasticizer by immersing the sheet-like molded body in an extraction solvent and sufficiently drying it can be mentioned.
- the method for extracting the plasticizer may be either a batch type or a continuous type.
- the residual amount of plasticizer in the porous film is preferably less than 1% by mass.
- extraction solvent it is preferable to use a solvent that is a poor solvent for the polyolefin resin and a good solvent for the plasticizer and has a boiling point lower than the melting point of the polyolefin resin.
- extraction solvents include hydrocarbons such as n-hexane and cyclohexane; halogenated hydrocarbons such as methylene chloride and 1,1,1-trichloroethane; non-chlorine such as hydrofluoroether and hydrofluorocarbon Halogenated solvents; alcohols such as ethanol and isopropanol; ethers such as diethyl ether and tetrahydrofuran; ketones such as acetone and methyl ethyl ketone.
- These extraction solvents may be recovered and reused by an operation such as distillation.
- heat treatment such as heat fixation or heat relaxation can be performed after the stretching process or after the porous film is formed.
- the porous film may be subjected to a post-treatment such as a hydrophilic treatment with a surfactant or the like, or a cross-linking treatment with ionizing radiation.
- the multilayer porous membrane of this Embodiment is excellent in heat resistance and has a shutdown function, and is therefore suitable for a battery separator that separates a positive electrode and a negative electrode in a battery.
- the multilayer porous membrane of the present embodiment is not easily short-circuited even at high temperatures, and can be used safely as a separator for a high electromotive force battery.
- a non-aqueous electrolyte battery for example, a non-aqueous electrolyte battery can be cited, and the multilayer porous film of the present embodiment is disposed between the positive electrode and the negative electrode to hold the non-aqueous electrolyte, thereby A water electrolyte battery can be manufactured.
- a positive electrode there is no limitation in a positive electrode, a negative electrode, and a non-aqueous electrolyte
- the positive electrode material include lithium-containing composite oxides such as LiCoO 2 , LiNiO 2 , spinel type LiMnO 4 , and olivine type LiFePO 4
- examples of the negative electrode material include graphite, non-graphitizable carbonaceous, and easy graphite.
- Carbonaceous materials such as carbonaceous carbonaceous and composite carbon bodies; silicon, tin, metallic lithium, various alloy materials, and the like.
- an electrolyte in which an electrolyte is dissolved in an organic solvent can be used.
- the organic solvent include propylene carbonate, ethylene carbonate, dimethyl carbonate, diethyl carbonate, and ethyl methyl carbonate.
- lithium salts such as LiClO 4 , LiBF 4 , and LiPF 6 .
- the air permeability of the multilayer porous membrane is preferably 10 seconds / 100 cc or more and 650 seconds / 100 cc or less, more preferably 20 seconds / 100 cc or more and 500 seconds / 100 cc or less. More preferably, it is 30 seconds / 100 cc or more and 450 seconds / 100 cc or less, and particularly preferably 50 seconds / 100 cc or more and 400 seconds / 100 cc or less.
- the air permeability is 10 seconds / 100 cc or more, self-discharge tends to decrease when used as a battery separator, and when it is 650 seconds / 100 cc or less, good charge / discharge characteristics tend to be obtained.
- the rate of increase in the air permeability of the multilayer porous membrane due to the formation of the porous layer is preferably 0% or more and 200% or less, more preferably 0% or more and 100% or less, and more preferably 0% or more and 75%. More preferably, it is more preferably 0% or more and 50% or less.
- the increase in the air permeability of the multilayer porous film after forming the porous layer can be preferably used if it is 0% or more and 500% or less.
- the final film thickness of the multilayer porous membrane is preferably 2 ⁇ m or more and 200 ⁇ m or less, more preferably 5 ⁇ m or more and 100 ⁇ m or less, and further preferably 7 ⁇ m or more and 30 ⁇ m or less.
- the film thickness is 2 ⁇ m or more, the mechanical strength tends to be sufficient, and when the film thickness is 200 ⁇ m or less, the occupied volume of the separator is reduced, which tends to be advantageous in terms of increasing the battery capacity.
- the thermal shrinkage rate of the multilayer porous film at 150 ° C. is preferably 0% or more and 15% or less in both the MD direction and the TD direction, more preferably 0% or more and 10% or less, and further preferably 0% or more and 5% or less. It is. When the thermal shrinkage rate is 15% or less in both the MD direction and the TD direction, it is preferable because film breakage of the multilayer porous membrane during abnormal heat generation of the battery is suppressed and short circuit is less likely to occur.
- the shutdown temperature of the multilayer porous membrane is preferably 120 ° C. or higher and 160 ° C. or lower, more preferably 120 ° C. or higher and 150 ° C. or lower. It is preferable that the shutdown temperature is 160 ° C. or lower because even when the battery generates heat, current interruption is promptly promoted, and better safety performance tends to be obtained. On the other hand, it is preferable that the shutdown temperature is 120 ° C. or higher because the battery can be used at around 100 ° C.
- the short-circuit temperature of the multilayer porous membrane is preferably 180 ° C. or higher and 1000 ° C. or lower, more preferably 200 ° C. or higher and 1000 ° C. or lower. If the short-circuit temperature is 180 ° C. or higher, even if abnormal heat generation occurs in the battery, a short-circuit does not occur immediately.
- the short temperature can be controlled to a desired value by adjusting the content of polypropylene, the type of polyolefin other than polypropylene, the type of inorganic particles, the thickness of the inorganic particle-containing layer, and the like. In addition, about the various parameters mentioned above, unless otherwise indicated, it measures according to the measuring method in the Example mentioned later.
- Air permeability of porous membrane (second / 100cc), rate of increase (increase) in air permeability due to formation of porous layer (%)
- a Gurley type air permeability meter (Toyo Seiki G-B2 (trademark), inner cylinder mass: 567 g) according to JIS P-8117, a porous film having an area of 645 mm 2 (a circle with a diameter of 28.6 mm), multilayer porosity
- the time (seconds) required for 100 cc of air to pass through the membrane was measured and used as the air permeability of the porous membrane and the multilayer porous membrane.
- the rate of increase in air permeability due to the formation of the porous layer was calculated by the following formula.
- Air permeability increase rate (%) ⁇ (Air permeability of multilayer porous membrane ⁇ Air permeability of porous membrane) / Air permeability of porous membrane ⁇ ⁇ 100
- This laminate is set on a hot plate, heated at a rate of 15 ° C./min with a pressure of 4.1 MPa applied by a hydraulic press, and the impedance change between the positive and negative electrodes is 1 V AC and 1 kHz.
- the measurement was performed up to 200 ° C.
- the temperature at the time when the impedance reached 1000 ⁇ was taken as the shutdown temperature, and the temperature when the impedance again fell below 1000 ⁇ after the shutdown was taken as the short-circuit temperature.
- the negative electrode, the multilayer porous film, and the positive electrode were stacked in this order from the bottom so that the active material surfaces of the positive electrode and the negative electrode faced each other.
- the laminate was stored in a stainless steel container with a lid in which the container main body and the lid were insulated so that the copper foil of the negative electrode and the aluminum foil of the positive electrode were in contact with the container main body and the lid, respectively.
- a non-aqueous electrolyte was poured into the container and sealed.
- step 1 The simple battery assembled in step 1 is charged to a battery voltage of 4.2 V at a current value of 3 mA (about 0.5 C) at 25 ° C., and the current value starts to be reduced from 3 mA so as to hold 4.2 V.
- the first charge after battery preparation was performed for a total of about 6 hours, and then discharged to a battery voltage of 3.0 V at a current value of 3 mA.
- the battery is charged to a battery voltage of 4.2 V at a current value of 6 mA (about 1.0 C), and the current value starts to be reduced from 6 mA so as to hold 4.2 V.
- the battery was charged for a period of time and then discharged at a current value of 6 mA to a battery voltage of 3.0 V, and the discharge capacity at that time was set to 1 C discharge capacity (mAh).
- the battery is charged to a battery voltage of 4.2 V at a current value of 6 mA (about 1.0 C), and the current value starts to be reduced from 6 mA so as to hold 4.2 V.
- the battery was charged for a period of time and then discharged at a current value of 12 mA (about 2.0 C) to a battery voltage of 3.0 V, and the discharge capacity at that time was set to 2 C discharge capacity (mAh).
- the ratio of the 2C discharge capacity to the 1C discharge capacity was calculated, and this value was used as the rate characteristic.
- Rate characteristic (%) (2C discharge capacity / 1C discharge capacity) ⁇ 100
- Cycle characteristics A simple battery that has been evaluated for rate characteristics is charged to a battery voltage of 4.2 V at a current value of 6 mA (about 1.0 C) at 60 ° C., and then the current value starts to be reduced from 6 mA so as to maintain 4.2 V.
- a cycle of charging for about 3 hours in total and discharging to a battery voltage of 3.0 V at a current value of 6 mA was repeated 100 times, and the discharge capacities (mAh) of the first cycle and the 100th cycle were measured. The ratio of the discharge capacity at the 100th cycle to the discharge capacity at the first time was calculated, and this value was used as the cycle characteristics.
- Cycle characteristics (%) (100th discharge capacity / first discharge capacity) ⁇ 100
- Porosity (1 ⁇ mass / volume / 0.95) ⁇ 100
- DSC210 suggestion thermal analysis measuring apparatus
- the particles mainly composed of an aluminum silicate compound used in Examples 1-1 to 1-19 and Comparative Examples 1-1 to 1-4 are as follows.
- Kaolin 1, 2, 3, 5 An aluminosilicate mineral mainly composed of kaolinite (Al 2 Si 2 O 5 (OH) 4 ).
- Kaolin 4 An aluminosilicate mineral containing pyrophyllite (Al 2 Si 4 O 10 (OH) 2 ) as a main component.
- Kaolin 6 and 7 Kaolin 4 is wet-ground by a bead mill.
- Firing kaolin 1 A kaolin containing kaolinite as a main component and calcined at high temperature.
- Firing kaolin 2 A powder obtained by wet-grinding calcining kaolin 1 with a bead mill.
- Synthetic aluminum silicate 1 chemically synthesized aluminum silicate.
- Synthetic aluminum silicate 2, 3 A synthetic aluminum silicate 1 wet-ground in a bead mill. The particle size distribution and average particle size of each particle are shown in Table 1.
- Example 1-1 47 parts by mass of polyethylene having an Mv of 700,000, 46 parts by mass of polyethylene having an Mv of 250,000 and 7 parts by mass of polypropylene having an Mv of 400,000 were homogenized using a tumbler blender. 1% by mass of pentaerythrityl-tetrakis- [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] as an antioxidant was added to 99% by mass of the obtained pure polymer mixture, and again A mixture such as a polymer was obtained by dry blending using a tumbler blender. The obtained mixture of polymers and the like was substituted with nitrogen and then fed to the twin-screw extruder with a feeder under a nitrogen atmosphere.
- liquid paraffin (kinematic viscosity at 37.78 ° C .: 7.59 ⁇ 10 ⁇ 5 m 2 / s) was injected as a plasticizer into the extruder cylinder by a plunger pump.
- the feeder and pump were adjusted so that the liquid paraffin content ratio in the total mixture melt-kneaded and extruded was 65% by mass.
- the melt-kneading conditions were set at a preset temperature of 200 ° C., a screw rotation speed of 240 rpm, and a discharge rate of 12 kg / h.
- the melt-kneaded product was extruded and cast on a cooling roll controlled at a surface temperature of 25 ° C. through a T die to obtain a sheet-like polyolefin composition having a thickness of 2000 ⁇ m.
- the simultaneous biaxial tenter stretching machine led to the simultaneous biaxial tenter stretching machine, and simultaneous biaxial stretching was performed 7 times in the MD direction and 7 times in the TD direction.
- the setting temperature of the simultaneous biaxial tenter was 125 ° C.
- the solution was introduced into a methyl ethyl ketone tank, and liquid paraffin was extracted and removed, and then methyl ethyl ketone was removed by drying. Further, it was guided to a TD tenter heat fixing machine and heat fixed.
- the heat setting temperature was 133 ° C. and the TD relaxation rate was 0.80.
- a polyolefin resin porous film having a film thickness of 16 ⁇ m, a porosity of 40%, and an air permeability of 160 seconds / 100 cc was obtained.
- kaolin 1 in Table 1 150 parts by weight of polyvinyl alcohol (hereinafter sometimes abbreviated as “PVA”. Average polymerization degree 1700, saponification degree 99% or more) 150 parts by weight.
- a coating solution was prepared by uniformly dispersing in part by mass of water, and applied to the surface of the polyolefin resin porous film using a gravure coater. Water was removed by drying at 60 ° C. to obtain a multilayer porous membrane in which a porous layer having a thickness of 4 ⁇ m was formed on the polyolefin resin porous membrane.
- Example 1-2 A multilayer porous membrane was obtained in the same manner as in Example 1-1 except that the kaolin 2 in Table 1 was used and the thickness of the porous layer was 3 ⁇ m.
- Example 1-3 A multilayer porous membrane was obtained in the same manner as in Example 1-1 except that kaolin 3 in Table 1 was used.
- Example 1-4 A coating solution was prepared by uniformly dispersing 97.5 parts by weight of kaolin 7 in Table 1 and 2.5 parts by weight of polyvinyl alcohol (average polymerization degree 1700, saponification degree 99% or more) in 150 parts by weight of water.
- a multilayer porous membrane was obtained in the same manner as in Example 1-1 except that a porous layer having a thickness of 5 ⁇ m was formed on the polyolefin resin porous membrane.
- Example 1-5 A coating solution is prepared by uniformly dispersing 97.0 parts by weight of calcined kaolin 1 in Table 1 and 3.0 parts by weight of polyvinyl alcohol (average polymerization degree 1700, saponification degree 99% or more) in 150 parts by weight of water.
- a multilayer porous membrane was obtained in the same manner as in Example 1-1 except that.
- Example 1-6 A multilayer porous membrane was obtained in the same manner as in Example 1-1 except that the calcined kaolin 2 shown in Table 1 was used.
- Example 1-7 95.0 parts by mass of the calcined kaolin 2 in Table 1 and 5.0 parts by mass of acrylic latex (Acl LTX, solid concentration 40%, average particle size 90 nm, minimum film forming temperature 0 ° C.
- ammonium polycarboxylate aqueous solution (San Nopco) SN Dispersant 5468) 1 part by weight and 1 part by weight of polyoxyalkylene surfactant (Sannopco SN Wet 980) are uniformly dispersed in 150 parts by weight of water to prepare a coating solution, on the polyolefin resin porous membrane
- a multilayer porous membrane was obtained in the same manner as in Example 1-1 except that a porous layer having a thickness of 6 ⁇ m was formed.
- Example 1-8 47.5 parts by mass of Mv 700,000 homopolymer polyethylene, 47.5 parts by mass of Mv 250,000 homopolymer polyethylene, and 5 parts by mass of Mv 400,000 homopolymer polypropylene were dry blended using a tumbler blender. 1% by mass of pentaerythrityl-tetrakis- [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] as an antioxidant was added to 99% by mass of the obtained pure polymer mixture, and again A mixture such as a polymer was obtained by dry blending using a tumbler blender.
- the obtained mixture of polymers and the like was substituted with nitrogen and then fed to the twin-screw extruder with a feeder under a nitrogen atmosphere. Further, liquid paraffin (kinematic viscosity at 37.78 ° C .: 7.59 ⁇ 10 ⁇ 5 m 2 / s) was injected as a plasticizer into the extruder cylinder by a plunger pump. The feeder and pump were adjusted so that the liquid paraffin content ratio in the total mixture melt-kneaded and extruded was 65% by mass. The melt-kneading conditions were set at a preset temperature of 200 ° C., a screw rotation speed of 240 rpm, and a discharge rate of 12 kg / h.
- melt-kneaded material was extruded and cast on a cooling roll controlled at a surface temperature of 25 ° C. through a T-die to obtain a sheet-like polyolefin composition having a thickness of 1300 ⁇ m.
- the simultaneous biaxial tenter stretching machine led to the simultaneous biaxial tenter stretching machine, and simultaneous biaxial stretching was performed 7 times in the MD direction and 6.4 times in the TD direction.
- the set temperature of the simultaneous biaxial tenter was 118 ° C.
- the solution was introduced into a methyl ethyl ketone tank, and liquid paraffin was extracted and removed, and then methyl ethyl ketone was removed by drying. Further, it was guided to a TD tenter heat fixing machine and heat fixed.
- the heat setting temperature was 122 ° C. and the TD relaxation rate was 0.80.
- a coating solution is prepared by uniformly dispersing 98.2 parts by mass of calcined kaolin 2 in Table 1 and 1.8 parts by mass of polyvinyl alcohol (average polymerization degree 1700, saponification degree 99% or more) in 150 parts by mass of water. And it apply
- Example 1-9 A multilayer porous membrane was obtained in the same manner as in Example 1-6 except that the thickness of the porous membrane was 12 ⁇ m, the porosity was 40%, and the air permeability was 120 seconds / 100 cc.
- Example 1-10 A coating solution is prepared by uniformly dispersing 97.0 parts by weight of calcined kaolin 2 in Table 1 and 3.0 parts by weight of polyvinyl alcohol (average polymerization degree 1700, saponification degree 99% or more) in 150 parts by weight of water.
- a multilayer porous membrane was obtained in the same manner as in Example 1-9 except that.
- Example 1-11 A multi-layer porous film was formed in the same manner as in Example 1-10 except that the porous film thickness was 20 ⁇ m, the porosity was 40%, the air permeability was 280 sec / 100 cc, and the porous layer thickness was 7 ⁇ m. A membrane was obtained.
- Example 1-12 A coating solution in which 97.5 parts by weight of synthetic aluminum silicate 2 in Table 1 and 2.5 parts by weight of polyvinyl alcohol (average polymerization degree 1700, saponification degree 99% or more) are uniformly dispersed in 150 parts by weight of water.
- a multilayer porous membrane was obtained in the same manner as in Example 1-1 except that a porous layer having a thickness of 6 ⁇ m was formed on the polyolefin resin porous membrane.
- Example 1-13 A multilayer porous membrane was obtained in the same manner as in Example 1-12 except that the synthetic aluminum silicate 3 shown in Table 1 was used.
- Example 1-14 A coating solution was prepared by uniformly dispersing 95.0 parts by weight of kaolin 7 in Table 1 and 5.0 parts by weight of polyvinyl alcohol (average polymerization degree 1700, saponification degree 99% or more) in 150 parts by weight of water.
- a multilayer porous membrane was obtained in the same manner as in Example 1-9 except that a porous layer having a thickness of 5 ⁇ m was formed on the polyolefin resin porous membrane.
- Example 1-15 A coating solution was prepared by uniformly dispersing 97.5 parts by weight of kaolin 4 in Table 1 and 2.5 parts by weight of polyvinyl alcohol (average polymerization degree 1700, saponification degree 99% or more) in 150 parts by weight of water.
- a multilayer porous membrane was obtained in the same manner as in Example 1-1 except that a porous layer having a thickness of 7 ⁇ m was formed on the polyolefin resin porous membrane.
- Example 1-16 A multilayer porous membrane was obtained in the same manner as in Example 1-1 except that a kaolin 5 of Table 1 was used to form a porous layer having a thickness of 7 ⁇ m on the polyolefin resin porous membrane.
- Example 1-17 A multilayer porous membrane was obtained in the same manner as in Example 1-15 except that kaolin 6 in Table 1 was used.
- Example 1-18 A multilayer porous membrane was obtained in the same manner as in Example 1-15 except that the synthetic aluminum silicate 1 shown in Table 1 was used to form a porous layer having a thickness of 10 ⁇ m on the polyolefin resin porous membrane.
- Example 1-19 By forming a porous layer with a thickness of 3 ⁇ m on one side of the polyolefin resin porous membrane and then forming a porous layer with a thickness of 3 ⁇ m on the other side of the same porous polyolefin resin membrane, A multilayer porous membrane was obtained in the same manner as in Example 1-7, except that a porous layer having a total thickness of 3 ⁇ m and a total thickness of 6 ⁇ m was formed.
- Example 1-1 A porous membrane was obtained in the same manner as in Example 1-1 except that the porous layer was not formed.
- Example 1-2 A porous membrane was obtained in the same manner as in Example 1-8, except that the porous layer was not formed.
- Example 1-3 A porous membrane was obtained in the same manner as in Example 1-9, except that no porous layer was formed.
- Example 1-4 A porous membrane was obtained in the same manner as in Example 1-11 except that the porous layer was not formed.
- Table 2 shows the air permeability and air permeability increase rate, 150 ° C. heat shrinkage rate, shutdown temperature and short-circuit temperature of the multilayer porous membranes prepared in Examples 1-1 to 1-19 and Comparative Examples 1-1 to 1-4. Shown in The porous films of Comparative Examples 1-1 to 1-4 in which no porous layer was formed exhibited a very large value with a thermal shrinkage rate at 150 ° C. exceeding 50%.
- Examples 1-15 to 1- in which a porous layer using particles mainly composed of an aluminum silicate compound in which particles having a particle size of 0.2 ⁇ m to 1.4 ⁇ m were less than 2% of the total particles were formed.
- the thermal shrinkage at 150 ° C. was suppressed as compared with the porous membranes of Comparative Examples 1-1 to 1-4 in which no porous layer was formed, but the thickness of the porous layer was 7 ⁇ m or more. Even in this case, the value was 15% or more in the MD direction and 15% or more in the TD direction.
- Examples 1-1 to 1-1 in which porous layers using particles mainly composed of an aluminum silicate compound in which 2% or more of the particles are larger than 0.2 ⁇ m and 1.4 ⁇ m or less in diameter are formed. 14.
- the multilayer porous membrane of Example 1-19 has a thin alumina porous layer thickness of 3 to 7 ⁇ m, the thermal shrinkage rate at 150 ° C. is 5% or less in both the MD and TD directions. It was very small and showed good heat shrinkage characteristics.
- the shutdown temperatures of the multilayer porous membranes or porous membranes of Examples 1-1 to 1-19 and Comparative Examples 1-1 to 1-4 were 145 to 148 ° C. and had a good shutdown function.
- the porous films of Comparative Examples 1-1 to 1-4 in which the porous layer was not formed were short-circuited only by heating to the shutdown temperature + several degrees Celsius, but the porous layer composed of particles mainly composed of an aluminum silicate compound All of the formed multilayer porous films of Examples 1-1 to 1-19 were not short-circuited even when heated to 200 ° C. or higher, and were excellent in heat resistance.
- the air permeability of each of the multilayer porous membranes of Examples 1-1 to 1-14 and 1-19 was as small as 300 seconds / 100 CC or less. In particular, even when compared with the porous films of Comparative Examples 1-1 to 1-4 in which no porous layer was formed, the rate of increase in air permeability could be suppressed to 100% or less.
- the particles mainly composed of an aluminum silicate compound used in Examples 2-1 to 2-20 and Comparative Examples 2-1 to 2-4 are as follows.
- Kaolin 1, 2, 3, 5, 8 An aluminosilicate mineral mainly composed of kaolinite (Al 2 Si 2 O 5 (OH) 4 ).
- Kaolin 4, 6, 7 Aluminosilicate mineral containing pyrophyllite (Al 2 Si 4 O 10 (OH) 2 ) as a main component.
- Kaolins 4 and 6 are obtained by wet pulverizing kaolin 7 with a bead mill.
- Firing kaolin 1, 2 A kaolin containing kaolinite as a main component and calcined at high temperature.
- the calcined kaolin 1 is obtained by wet-grinding the calcined kaolin 2 with a bead mill.
- Synthetic aluminum silicate 1, 2, 3 chemically synthesized aluminum silicate.
- the synthetic aluminum silicates 1 and 2 are obtained by wet-pulverizing the synthetic aluminum silicate 3 with a bead mill.
- the average particle size of each particle is shown in Table 3.
- Example 2-1 47 parts by mass of polyethylene having an Mv of 700,000, 46 parts by mass of polyethylene having an Mv of 250,000 and 7 parts by mass of polypropylene having an Mv of 400,000 were homogenized using a tumbler blender. 1% by mass of pentaerythrityl-tetrakis- [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] as an antioxidant was added to 99% by mass of the obtained pure polymer mixture, and again A mixture such as a polymer was obtained by dry blending using a tumbler blender. The obtained mixture of polymers and the like was substituted with nitrogen and then fed to the twin-screw extruder with a feeder under a nitrogen atmosphere.
- liquid paraffin (kinematic viscosity at 37.78 ° C .: 7.59 ⁇ 10 ⁇ 5 m 2 / s) was injected as a plasticizer into the extruder cylinder by a plunger pump.
- the feeder and pump were adjusted so that the liquid paraffin content ratio in the total mixture melt-kneaded and extruded was 65% by mass.
- the melt-kneading conditions were set at a preset temperature of 200 ° C., a screw rotation speed of 240 rpm, and a discharge rate of 12 kg / h.
- the melt-kneaded product was extruded and cast on a cooling roll controlled at a surface temperature of 25 ° C. through a T die to obtain a sheet-like polyolefin composition having a thickness of 2000 ⁇ m.
- the simultaneous biaxial tenter stretching machine and simultaneous biaxial stretching was performed 7 times in the MD direction and 7 times in the TD direction.
- the setting temperature of the simultaneous biaxial tenter was 125 ° C.
- the solution was introduced into a methyl ethyl ketone tank, and liquid paraffin was extracted and removed, and then methyl ethyl ketone was removed by drying. Further, it was guided to a TD tenter heat fixing machine and heat fixed.
- the heat setting temperature was 133 ° C. and the TD relaxation rate was 0.80.
- a polyolefin resin porous film having a film thickness of 16 ⁇ m, a porosity of 40%, and an air permeability of 160 seconds / 100 cc was obtained.
- a coating solution was prepared by uniformly dispersing in water, and coated on the surface of the polyolefin resin porous film using a gravure coater. Water was removed by drying at 60 ° C. to obtain a multilayer porous membrane in which a porous layer having a thickness of 3 ⁇ m was formed on the polyolefin resin porous membrane.
- Example 2-2 A multilayer porous membrane was obtained in the same manner as in Example 2-1, except that kaolin 2 was used and the thickness of the porous layer was 4 ⁇ m.
- Example 2-3 A coating solution was prepared by uniformly dispersing 97.0 parts by weight of synthetic aluminum silicate 1 and 3.0 parts by weight of polyvinyl alcohol (average polymerization degree 1700, saponification degree 99% or more) in 150 parts by weight of water.
- a multilayer porous membrane was obtained in the same manner as in Example 2-1, except that a porous layer having a thickness of 6 ⁇ m was formed on the polyolefin resin porous membrane.
- Example 2-4 Except for preparing a coating solution by uniformly dispersing 97.5 parts by weight of calcined kaolin 1 and 2.5 parts by weight of polyvinyl alcohol (average polymerization degree 1700, saponification degree 99% or more) in 150 parts by weight of water. A multilayer porous membrane was obtained in the same manner as in Example 2-2.
- Example 2-5 A multilayer porous membrane was obtained in the same manner as in Example 2-2 except that kaolin 3 was used.
- Example 2-6 A multilayer porous membrane was obtained in the same manner as in Example 2-3 except that calcined kaolin 2 was used and the thickness of the porous layer was changed to 5 ⁇ m.
- Example 2-7 A multilayer porous membrane was obtained in the same manner as in Example 2-4 except that kaolin 4 was used and the thickness of the porous layer was changed to 6 ⁇ m.
- Example 2-8 A multilayer porous membrane was obtained in the same manner as in Example 2-1, except that kaolin 5 was used.
- Example 2-9 95.0 parts by mass of calcined kaolin 1 and 5.0 parts by mass of acrylic latex (hereinafter sometimes abbreviated as “Acl”; solid content concentration 40%, average particle size 90 nm, minimum film forming temperature 0 ° C. or less)
- a coating solution is prepared by uniformly dispersing 1 part by weight of an aqueous polycarboxylate aqueous solution (San Nopco SN Dispersant 5468) and 1 part by weight of a polyoxyalkylene surfactant (San Nopco SN Wet 980) in 150 parts by weight of water.
- a multilayer porous membrane was obtained in the same manner as in Example 2-1, except that a porous layer having a thickness of 7 ⁇ m was formed on the polyolefin resin porous membrane.
- Example 2-10 47.5 parts by mass of Mv 700,000 homopolymer polyethylene, 47.5 parts by mass of Mv 250,000 homopolymer polyethylene, and 5 parts by mass of Mv 400,000 homopolymer polypropylene were dry blended using a tumbler blender. 1% by mass of pentaerythrityl-tetrakis- [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] as an antioxidant was added to 99% by mass of the obtained pure polymer mixture, and again A mixture such as a polymer was obtained by dry blending using a tumbler blender.
- the obtained mixture of polymers and the like was substituted with nitrogen and then fed to the twin-screw extruder with a feeder under a nitrogen atmosphere. Further, liquid paraffin (kinematic viscosity at 37.78 ° C .: 7.59 ⁇ 10 ⁇ 5 m 2 / s) was injected as a plasticizer into the extruder cylinder by a plunger pump. The feeder and pump were adjusted so that the liquid paraffin content ratio in the total mixture melt-kneaded and extruded was 65% by mass. The melt-kneading conditions were set at a preset temperature of 200 ° C., a screw rotation speed of 240 rpm, and a discharge rate of 12 kg / h.
- the melt-kneaded material was extruded and cast on a cooling roll controlled at a surface temperature of 25 ° C. through a T-die to obtain a sheet-like polyolefin composition having a thickness of 1300 ⁇ m.
- the simultaneous biaxial tenter stretching machine and simultaneous biaxial stretching was performed 7 times in the MD direction and 6.4 times in the TD direction.
- the set temperature of the simultaneous biaxial tenter was 118 ° C.
- the solution was introduced into a methyl ethyl ketone tank, and liquid paraffin was extracted and removed, and then methyl ethyl ketone was removed by drying. Further, it was guided to a TD tenter heat fixing machine and heat fixed.
- the heat setting temperature was 122 ° C. and the TD relaxation rate was 0.80.
- a polyolefin resin porous film having a film thickness of 16 ⁇ m, a porosity of 49%, and an air permeability of 155 seconds / 100 cc was obtained.
- Example 2-11 A multilayer porous membrane was obtained in the same manner as in Example 2-1, except that the thickness of the porous membrane was 12 ⁇ m, the porosity was 40%, and the air permeability was 120 seconds / 100 cc.
- Example 2-12 Except for preparing a coating solution by uniformly dispersing 97.0 parts by weight of calcined kaolin 1 and 3.0 parts by weight of polyvinyl alcohol (average polymerization degree 1700, saponification degree 99% or more) in 150 parts by weight of water. A multilayer porous membrane was obtained in the same manner as in Example 2-11.
- Example 2-13 The film thickness of the porous film was 20 ⁇ m, the porosity was 40%, the air permeability was 280 seconds / 100 cc, 96.5 parts by weight of calcined kaolin 1 and polyvinyl alcohol (average polymerization degree 1700, saponification degree 99%)
- Example 2-1 except that a coating solution was prepared by uniformly dispersing 3.5 parts by weight in 150 parts by weight of water and forming a porous layer having a thickness of 6 ⁇ m on the polyolefin resin porous film.
- a multilayer porous membrane was obtained in the same manner.
- Example 2-14 A coating solution is prepared by uniformly dispersing 96.0 parts by weight of kaolin 4 and 4.0 parts by weight of polyvinyl alcohol (average polymerization degree 1700, saponification degree 99% or more) in 150 parts by weight of water, and polyolefin resin.
- a multilayer porous membrane was obtained in the same manner as in Example 2-11 except that a porous layer having a thickness of 4 ⁇ m was formed on the porous membrane.
- Example 2-15 A multilayer porous membrane was obtained in the same manner as in Example 2-4, except that kaolin 6 was used to form a porous layer having a thickness of 7 ⁇ m on the polyolefin resin porous membrane.
- Example 2-16 A multilayer porous membrane was obtained in the same manner as in Example 2-15 except that kaolin 7 was used.
- Example 2-17 A multilayer porous membrane was obtained in the same manner as in Example 2-1, except that kaolin 8 was used to form a porous layer having a thickness of 7 ⁇ m on the polyolefin resin porous membrane.
- Example 2-18 A multilayer porous membrane was obtained in the same manner as in Example 2-3, except that a synthetic aluminum silicate 2 was used to form a porous layer having a thickness of 7 ⁇ m on the polyolefin resin porous membrane.
- Example 2-19 A multilayer porous membrane was obtained in the same manner as in Example 2-4, except that a synthetic aluminum silicate 3 was used to form a porous layer having a thickness of 10 ⁇ m on the polyolefin resin porous membrane.
- Example 2-20 By forming a porous layer with a thickness of 3 ⁇ m on one side of the polyolefin resin porous membrane and then forming a porous layer with a thickness of 4 ⁇ m on the other side of the same porous polyolefin resin membrane, A multilayer porous membrane was obtained in the same manner as in Example 2-9 except that a porous layer having a total thickness of 7 ⁇ m was formed.
- Example 2-1 A porous membrane was obtained in the same manner as in Example 2-1, except that the porous layer was not formed.
- Example 2-2 A porous membrane was obtained in the same manner as in Example 2-10 except that the porous layer was not formed.
- Table 3 shows the air permeability and the air permeability increase rate, 150 ° C. heat shrinkage rate, shutdown temperature and short circuit temperature of the multilayer porous membranes prepared in Examples 2-1 to 2-20 and Comparative Examples 2-1 to 2-4. Shown in The porous films of Comparative Examples 2-1 to 2-4 in which the porous layer was not formed showed a very large value with a thermal shrinkage rate at 150 ° C. exceeding 50%.
- the multilayer porous membranes of Examples 2-15 to 2-19 in which a porous layer using particles mainly composed of an aluminum silicate compound having an average particle size of less than 0.1 ⁇ m or greater than 4.0 ⁇ m was formed Compared with the porous membranes of Comparative Examples 2-1 to 2-4 that did not form a film, the thermal shrinkage rate at 150 ° C. was suppressed, but even when the thickness of the porous layer was 7 ⁇ m or more, 10% in the MD direction. As described above, the value was 10% or more in the TD direction.
- Examples 2-1 to 2-14 and Examples 2-20 in which porous layers using particles mainly composed of an aluminum silicate compound having an average particle size of 0.1 ⁇ m to 4.0 ⁇ m were used.
- the multi-layer porous membrane has a heat shrinkage rate at 150 ° C. of 5% or less in both MD and TD directions, despite the fact that the alumina porous layer is as thin as 3 to 7 ⁇ m. The shrinkage characteristics were shown.
- the shutdown temperatures of the multilayer porous membranes or porous membranes of Examples 2-1 to 2-20 and Comparative Examples 2-1 to 2-4 were 145 to 148 ° C. and had a good shutdown function.
- porous films of Comparative Examples 2-1 to 2-4 in which no porous layer was formed, were short-circuited only by heating to the shutdown temperature + several degrees Celsius, but the porous layer composed of particles mainly composed of an aluminum silicate compound All of the formed multilayer porous membranes of Examples 2-1 to 2-20 were not short-circuited even when heated to 200 ° C. or higher, and were extremely excellent in heat resistance.
- the air permeability of each of the multilayer porous membranes of Examples 2-1 to 2-14 and Example 2-20 was as small as 300 seconds / 100 CC or less.
- the rate of increase in air permeability could be suppressed to 60% or less.
- the simple batteries using the multilayer porous membranes or porous membranes of Examples 2-1 to 2-20 and Comparative Examples 2-1 to 2-4 as separators exhibited rate characteristics and cycle characteristics of 90% or more. . From this, it was confirmed that the multilayer porous membrane or porous membrane produced in Examples 2-1 to 2-20 and Comparative Examples 2-1 to 2-4 can be used as a battery separator.
- Examples 3-1 to 3-5, Comparative examples 3-1 to 3-2 are particles mainly composed of the following aluminum silicate compounds, silica, and alumina.
- Baked kaolin 1, 2 A kaolin containing kaolinite (Al 2 Si 2 O 5 (OH) 4 ) as a main component and calcined at high temperature.
- Kaolin 1 and 2 Aluminosilicate minerals mainly composed of kaolinite (Al 2 Si 2 O 5 (OH) 4 ).
- Synthetic aluminum silicate Chemically synthesized aluminum silicate.
- Table 4 shows the presence / absence of heat of reaction with the electrolyte, together with the average particle diameter, composition, and X-ray diffraction pattern of the inorganic particles used this time.
- the calcined kaolin did not show a peak due to the heat of reaction with the electrolyte solution, and the same result as alumina, which is known to be chemically very stable, was obtained.
- Example 3-6 47 parts by mass of polyethylene having an Mv of 700,000, 46 parts by mass of polyethylene having an Mv of 250,000 and 7 parts by mass of polypropylene having an Mv of 400,000 were homogenized using a tumbler blender. 1% by mass of pentaerythrityl-tetrakis- [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] as an antioxidant was added to 99% by mass of the obtained pure polymer mixture, and again A mixture such as a polymer was obtained by dry blending using a tumbler blender. The obtained mixture of polymers and the like was substituted with nitrogen and then fed to the twin-screw extruder with a feeder under a nitrogen atmosphere.
- liquid paraffin (kinematic viscosity at 37.78 ° C .: 7.59 ⁇ 10 ⁇ 5 m 2 / s) was injected as a plasticizer into the extruder cylinder by a plunger pump.
- the feeder and pump were adjusted so that the liquid paraffin content ratio in the total mixture melt-kneaded and extruded was 65% by mass.
- the melt-kneading conditions were set at a preset temperature of 200 ° C., a screw rotation speed of 240 rpm, and a discharge rate of 12 kg / h.
- the melt-kneaded product was extruded and cast on a cooling roll controlled at a surface temperature of 25 ° C. through a T die to obtain a sheet-like polyolefin composition having a thickness of 2000 ⁇ m.
- the simultaneous biaxial tenter stretching machine and simultaneous biaxial stretching was performed 7 times in the MD direction and 7 times in the TD direction.
- the setting temperature of the simultaneous biaxial tenter was 125 ° C.
- the solution was introduced into a methyl ethyl ketone tank, and liquid paraffin was extracted and removed, and then methyl ethyl ketone was removed by drying. Further, it was guided to a TD tenter heat fixing machine and heat fixed.
- the heat setting temperature was 133 ° C. and the TD relaxation rate was 0.80.
- a polyolefin resin porous film having a film thickness of 16 ⁇ m, a porosity of 40%, and an air permeability of 160 seconds / 100 cc was obtained.
- Example 3-7 A coating solution was prepared by uniformly dispersing 96.5 parts by weight of calcined kaolin 1 and 3.5 parts by weight of polyvinyl alcohol (average polymerization degree 1700, saponification degree 99% or more) in 150 parts by weight of water, and polyolefin.
- a multilayer porous membrane was obtained in the same manner as in Example 3-6, except that a porous layer having a thickness of 5 ⁇ m was formed on the resin porous membrane.
- Example 3-8 A multilayer porous membrane was obtained in the same manner as in Example 3-6, except that calcined kaolin 1 obtained by wet pulverizing calcined kaolin 1 with a bead mill was used.
- Example 3-9 A coating solution was prepared by uniformly dispersing 97.0 parts by weight of calcined kaolin 3 and 3.0 parts by weight of polyvinyl alcohol (average polymerization degree 1700, saponification degree 99% or more) in 150 parts by weight of water, and polyolefin.
- a multilayer porous membrane was obtained in the same manner as in Example 3-6, except that a porous layer having a thickness of 5 ⁇ m was formed on the resin porous membrane.
- Example 3-10 94.0 parts by mass of calcined kaolin 3 and acrylic latex (solid content concentration 40%, average particle size 90 nm, minimum film forming temperature 0 ° C. or less) 6.0 parts by mass, aqueous ammonium polycarboxylate (San Nopco SN Dispersant 5468) ) 1 part by weight, 1 part by weight of a polyoxyalkylene surfactant (San Nopco SN wet 980) was uniformly dispersed in 150 parts by weight of water to prepare a coating solution, and the thickness of the microporous polyolefin resin film was 6 ⁇ m.
- a multilayer porous membrane was obtained in the same manner as in Example 3-6 except that the porous layer was formed.
- Example 3-11 A coating solution is prepared by uniformly dispersing 98.2 parts by weight of calcined kaolin 3 and 1.8 parts by weight of polyvinyl alcohol (average polymerization degree 1700, saponification degree 99% or more) in 150 parts by weight of water, and polyolefin.
- a multilayer porous membrane was obtained in the same manner as in Example 3-6 except that a porous layer having a thickness of 7 ⁇ m was formed on the resin porous membrane.
- Example 3-12 A multilayer porous membrane was obtained in the same manner as in Example 3-9 except that a porous layer having a thickness of 8 ⁇ m was formed on the polyolefin resin porous membrane.
- Example 3-13 A multilayer porous membrane was obtained in the same manner as in Example 3-8 except that a porous layer having a thickness of 10 ⁇ m was formed on the polyolefin resin porous membrane.
- Example 3-14 Manufacture of porous membrane 47.5 parts by mass of Mv 700,000 homopolymer polyethylene, 47.5 parts by mass of Mv 250,000 homopolymer polyethylene, and 5 parts by mass of Mv 400,000 homopolymer polypropylene were dry blended using a tumbler blender. 1% by mass of pentaerythrityl-tetrakis- [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] as an antioxidant was added to 99% by mass of the obtained pure polymer mixture, and again A mixture such as a polymer was obtained by dry blending using a tumbler blender.
- the obtained mixture of polymers and the like was substituted with nitrogen and then fed to the twin-screw extruder with a feeder under a nitrogen atmosphere. Further, liquid paraffin (kinematic viscosity at 37.78 ° C .: 7.59 ⁇ 10 ⁇ 5 m 2 / s) was injected as a plasticizer into the extruder cylinder by a plunger pump. The feeder and pump were adjusted so that the liquid paraffin content ratio in the total mixture melt-kneaded and extruded was 65% by mass. The melt-kneading conditions were set at a preset temperature of 200 ° C., a screw rotation speed of 240 rpm, and a discharge rate of 12 kg / h.
- the melt-kneaded material was extruded and cast on a cooling roll controlled at a surface temperature of 25 ° C. through a T-die to obtain a sheet-like polyolefin composition having a thickness of 1300 ⁇ m.
- the set temperature of the simultaneous biaxial tenter was 118 ° C.
- the solution was introduced into a methyl ethyl ketone tank, and liquid paraffin was extracted and removed, and then methyl ethyl ketone was removed by drying.
- Example 3-15 The film thickness of the porous film was 12 ⁇ m, the porosity was 40%, the air permeability was 120 seconds / 100 cc, 97.5 parts by weight of calcined kaolin 3 and polyvinyl alcohol (average polymerization degree 1700, saponification degree 99% Example 3-6 except that 2.5 parts by weight were uniformly dispersed in 150 parts by weight of water to prepare a coating solution, and a porous layer having a thickness of 3 ⁇ m was formed on the polyolefin resin porous film. A multilayer porous membrane was obtained in the same manner.
- Example 3-16 A multilayer porous membrane was obtained in the same manner as in Example 3-9 except that the thickness of the porous membrane was 12 ⁇ m, the porosity was 40%, and the air permeability was 120 seconds / 100 cc.
- Example 3-17 The film thickness of the porous film was 20 ⁇ m, the porosity was 40%, the air permeability was 280 sec / 100 cc, 96.0 parts by weight of calcined kaolin 3 and polyvinyl alcohol (average polymerization degree 1700, saponification degree 99%)
- Example 3-6 except that 4.0 parts by weight was uniformly dispersed in 150 parts by weight of water to prepare a coating solution, and a porous layer having a thickness of 7 ⁇ m was formed on the polyolefin resin porous film.
- a multilayer porous membrane was obtained in the same manner.
- Example 3-18 A multilayer porous membrane was obtained in the same manner as in Example 3-11 except that kaolin 1 was used to form a porous layer having a thickness of 4 ⁇ m on the polyolefin resin porous membrane.
- Example 3-19 A multilayer porous membrane was obtained in the same manner as in Example 3-18 except that a porous layer having a thickness of 7 ⁇ m was formed on the polyolefin resin porous membrane.
- Example 3-20 A multilayer porous membrane was obtained in the same manner as in Example 3-18, except that kaolin 2 was used to form a porous layer having a thickness of 6 ⁇ m on the polyolefin resin porous membrane.
- Example 3-21 By forming a porous layer having a thickness of 4 ⁇ m on one surface of the polyolefin resin porous membrane and further forming a porous layer having a thickness of 4 ⁇ m on the other surface of the same polyolefin resin porous membrane, A multilayer porous membrane was obtained in the same manner as in Example 3-10 except that a porous layer having a total thickness of 4 ⁇ m and a total thickness of 8 ⁇ m was formed.
- Example 3-3 A multilayer porous membrane was obtained in the same manner as in Example 3-18 except that alumina was used.
- Comparative Example 3-4 A multilayer porous membrane was obtained in the same manner as in Comparative Example 3-3, except that a porous layer having a thickness of 7 ⁇ m was formed on the polyolefin resin porous membrane.
- Example 3-5 A porous membrane was obtained in the same manner as in Example 3-6 except that the porous layer was not formed.
- the temperature is shown in Table 5.
- the porous films of Comparative Examples 3-5 to 3-8 in which no porous layer was formed showed a very large value with a thermal shrinkage rate at 150 ° C. exceeding 50%.
- the density of the porous layer is 1.3 to 1.5 g / cm 3 when using particles containing kaolin as a main component, and 1.7 g / cm when using particles containing alumina having a large specific gravity as a main component. and cm 3, showed 1.6-2 times the value of the density (0.8g / cm 3) of the porous membrane.
- the multilayer porous membranes of Examples 3-6 to 3-17 and Example 3-21 in which the porous layer using particles containing calcined kaolin as a main component was formed were used in Examples 3-18 to 3-20.
- the heat shrinkage rate at 150 ° C. is very small at 5% or less in both the MD direction and the TD direction even if the porous layer is as thin as 3 to 7 ⁇ m. It showed good heat shrinkage characteristics.
- the density of the porous layer is 0.8 to 1.1 cm 3 , which is significantly smaller than the multilayer porous film using particles containing kaolin having the same specific gravity as the main component, and the density of the porous film (0.8 g / cm 3 ) And a very small value of about 1.4 times. This value did not change even when the thickness of the porous layer was increased to about 10 ⁇ m.
- the air permeability of each of the multilayer porous membranes of Examples 3-6 to 3-17 and Example 3-21 was as small as 300 seconds / 100 CC or less.
- the rate of increase in air permeability was very small, and when the thickness of the porous layer was 7 ⁇ m or less, 30% or less, 10 ⁇ m Even when the thickness was increased to about 40%, it could be suppressed to 40% or less. This is greatly suppressed as compared with the case where the multilayer porous film of Examples 3-18 to 3-21 in which a porous layer using particles containing kaolin as a main component is formed shows a value of around 50%. I understand that.
- the shutdown temperatures of the multilayer porous membranes or porous membranes of Examples 3-6 to 3-21 and Comparative Examples 3-3 to 3-8 were 145 to 148 ° C. and had a good shutdown function.
- the porous films of Comparative Examples 3-5 to 3-8 that did not form a porous layer were short-circuited only by heating to the shutdown temperature + several degrees Celsius, but formed a porous layer composed of particles containing calcined kaolin as a main component.
- the simple batteries using the multilayer porous membranes or porous membranes of Examples 3-6 to 3-21 and Comparative Examples 3-3 to 3-8 as separators exhibited rate characteristics and cycle characteristics of 90% or more. . From this, it was confirmed that the multilayer porous membrane or the porous membrane produced in Examples 3-6 to 3-21 and Comparative Examples 3-3 to 3-8 can be used as a battery separator.
- Example 4-1 to Example 4-4, Comparative Example 4-1 to 4-2 The inorganic particles used in Examples 4-5 to 4-18 and Comparative Examples 4-3 to 4-6 are particles mainly composed of the following aluminum silicate compounds, silica, and alumina.
- Loose clay An aluminosilicate mineral mainly composed of pyrophyllite (Al 2 Si 4 O 10 (OH) 2 ). This time we used a pharmacopoeia grade product.
- Kaolin 1 and 2 Aluminosilicate minerals mainly composed of kaolinite (Al 2 Si 2 O 5 (OH) 4 ).
- Synthetic aluminum silicate Chemically synthesized aluminum silicate.
- Table 6 shows the presence or absence of heat of reaction with the electrolyte, together with the average particle size, composition, and X-ray diffraction pattern of the inorganic particles used this time.
- the content of Si and O in the rhodolite clay is high, it was confirmed from the X-ray diffraction pattern that quartz was contained as an impurity.
- the wax stone clay did not show a peak due to the heat of reaction with the electrolytic solution, and the same result as alumina, which is known to be chemically very stable, was obtained.
- Example 4-5 Manufacture of porous membrane 47 parts by mass of polyethylene having an Mv of 700,000, 46 parts by mass of polyethylene having an Mv of 250,000 and 7 parts by mass of polypropylene having an Mv of 400,000 were homogenized using a tumbler blender. 1% by mass of pentaerythrityl-tetrakis- [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] as an antioxidant was added to 99% by mass of the obtained pure polymer mixture, and again A mixture such as a polymer was obtained by dry blending using a tumbler blender.
- the obtained mixture of polymers and the like was substituted with nitrogen and then fed to the twin-screw extruder with a feeder under a nitrogen atmosphere. Further, liquid paraffin (kinematic viscosity at 37.78 ° C .: 7.59 ⁇ 10 ⁇ 5 m 2 / s) was injected as a plasticizer into the extruder cylinder by a plunger pump. The feeder and pump were adjusted so that the liquid paraffin content ratio in the total mixture melt-kneaded and extruded was 65% by mass. The melt-kneading conditions were set at a preset temperature of 200 ° C., a screw rotation speed of 240 rpm, and a discharge rate of 12 kg / h.
- the melt-kneaded product was extruded and cast on a cooling roll controlled at a surface temperature of 25 ° C. through a T die to obtain a sheet-like polyolefin composition having a thickness of 2000 ⁇ m.
- the simultaneous biaxial tenter stretching machine and simultaneous biaxial stretching was performed 7 times in the MD direction and 7 times in the TD direction.
- the setting temperature of the simultaneous biaxial tenter was 125 ° C.
- the solution was introduced into a methyl ethyl ketone tank, and liquid paraffin was extracted and removed, and then methyl ethyl ketone was removed by drying. Further, it was guided to a TD tenter heat fixing machine and heat fixed.
- the heat setting temperature was 133 ° C. and the TD relaxation rate was 0.80.
- a polyolefin resin porous film having a film thickness of 16 ⁇ m, a porosity of 40%, and an air permeability of 160 seconds / 100 cc was obtained.
- Example 4-6 A coating solution is prepared by uniformly dispersing 95.0 parts by weight of a waxy clay and 5.0 parts by weight of polyvinyl alcohol (average degree of polymerization 1700, saponification degree 99% or more) in 150 parts by weight of water, and polyolefin.
- a multilayer porous membrane was obtained in the same manner as in Example 4-5 except that a porous layer having a thickness of 5 ⁇ m was formed on the resin porous membrane.
- Example 4-7 A multilayer porous membrane was obtained in the same manner as in Example 4-5 except that a porous layer having a thickness of 6 ⁇ m was formed on the polyolefin resin porous membrane.
- Example 4-8 A coating solution is prepared by uniformly dispersing 97.5 parts by weight of a waxy clay and 2.5 parts by weight of polyvinyl alcohol (average polymerization degree 1700, saponification degree 99% or more) in 150 parts by weight of water, and polyolefin.
- a multilayer porous membrane was obtained in the same manner as in Example 4-5 except that a porous layer having a thickness of 7 ⁇ m was formed on the resin porous membrane.
- Example 4-9 A multilayer porous membrane was obtained in the same manner as in Example 4-8 except that a porous layer having a thickness of 8 ⁇ m was formed on the polyolefin resin porous membrane.
- Example 4-10 94.0 parts by mass of waxy clay, acrylic latex (solid content concentration 40%, average particle size 90 nm, minimum film forming temperature 0 ° C. or less) 6.0 parts by mass, ammonium polycarboxylate aqueous solution (San Nopco SN Dispersant 5468) ) 1 part by weight, 1 part by weight of a polyoxyalkylene surfactant (San Nopco SN wet 980) was uniformly dispersed in 150 parts by weight of water to prepare a coating solution, and a 7 ⁇ m-thickness was formed on the polyolefin resin porous film.
- a multilayer porous membrane was obtained in the same manner as in Example 4-5 except that the porous layer was formed.
- Example 4-11 A multilayer porous membrane was obtained in the same manner as in Example 4-7, except that a porous layer having a thickness of 10 ⁇ m was formed on the polyolefin resin porous membrane.
- Example 4-12 Manufacture of porous membrane 47.5 parts by mass of Mv 700,000 homopolymer polyethylene, 47.5 parts by mass of Mv 250,000 homopolymer polyethylene, and 5 parts by mass of Mv 400,000 homopolymer polypropylene were dry blended using a tumbler blender. 1% by mass of pentaerythrityl-tetrakis- [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] as an antioxidant was added to 99% by mass of the obtained pure polymer mixture, and again A mixture such as a polymer was obtained by dry blending using a tumbler blender.
- the obtained mixture of polymers and the like was substituted with nitrogen and then fed to the twin-screw extruder with a feeder under a nitrogen atmosphere. Further, liquid paraffin (kinematic viscosity at 37.78 ° C .: 7.59 ⁇ 10 ⁇ 5 m 2 / s) was injected as a plasticizer into the extruder cylinder by a plunger pump. The feeder and pump were adjusted so that the liquid paraffin content ratio in the total mixture melt-kneaded and extruded was 65% by mass. The melt-kneading conditions were set at a preset temperature of 200 ° C., a screw rotation speed of 240 rpm, and a discharge rate of 12 kg / h.
- the melt-kneaded material was extruded and cast on a cooling roll controlled at a surface temperature of 25 ° C. through a T-die to obtain a sheet-like polyolefin composition having a thickness of 1300 ⁇ m.
- the simultaneous biaxial tenter stretching machine and simultaneous biaxial stretching was performed 7 times in the MD direction and 6.4 times in the TD direction.
- the set temperature of the simultaneous biaxial tenter was 118 ° C.
- the solution was introduced into a methyl ethyl ketone tank, and liquid paraffin was extracted and removed, and then methyl ethyl ketone was removed by drying. Further, it was guided to a TD tenter heat fixing machine and heat fixed.
- the heat setting temperature was 122 ° C. and the TD relaxation rate was 0.80.
- a polyolefin resin porous film having a film thickness of 16 ⁇ m, a porosity of 49%, and an air permeability of 155 seconds / 100 cc was obtained.
- 97.0 parts by mass of waxy clay and 3.0 parts by mass of polyvinyl alcohol are uniformly dispersed in 150 parts by mass of water to prepare a coating solution. And it apply
- Example 4-13 A multilayer porous membrane was obtained in the same manner as in Example 4-6 except that the thickness of the porous membrane was 12 ⁇ m, the porosity was 40%, and the air permeability was 120 seconds / 100 cc.
- Example 4-14 Example 4-6 except that the thickness of the porous membrane was 20 ⁇ m, the porosity was 40%, the air permeability was 280 sec / 100 cc, and a porous layer having a thickness of 7 ⁇ m was formed on the polyolefin resin porous membrane. In the same manner, a multilayer porous membrane was obtained.
- Example 4-15 Except for preparing a coating solution by uniformly dispersing 98.2 parts by weight of kaolin 1 and 1.8 parts by weight of polyvinyl alcohol (average polymerization degree 1700, saponification degree 99% or more) in 150 parts by weight of water. A multilayer porous membrane was obtained in the same manner as in Example 4-5.
- Example 4-16 A multilayer porous membrane was obtained in the same manner as in Example 4-15 except that a porous layer having a thickness of 7 ⁇ m was formed on the polyolefin resin porous membrane.
- Example 4-17 A multilayer porous membrane was obtained in the same manner as in Example 4-15, except that kaolin 2 was used and a porous layer having a thickness of 6 ⁇ m was formed on the polyolefin resin porous membrane.
- Example 4-18 By forming a porous layer having a thickness of 4 ⁇ m on one surface of the polyolefin resin porous membrane and further forming a porous layer having a thickness of 4 ⁇ m on the other surface of the same polyolefin resin porous membrane, A multilayer porous membrane was obtained in the same manner as in Example 4-10 except that a porous layer having a total thickness of 4 ⁇ m was formed.
- the temperature is shown in Table 7.
- the porous films of Comparative Examples 4-3 to 4-6 in which no porous layer was formed exhibited a very large value with a thermal shrinkage rate at 150 ° C. exceeding 50%.
- the multilayer porous membranes of Examples 4-15 to 4-17 in which the porous layer using particles containing kaolin as a main component was formed although the thickness of the porous layer was as thin as 4 to 7 ⁇ m, it was 150 ° C.
- the thermal shrinkage rate in the MD direction and the TD direction was as small as 5% or less, indicating good heat shrinkage characteristics.
- the density of the porous layer is 1.3 to 1.5 g / cm 3 , which is much larger than the density of the porous film (0.8 g / cm 3 ) when particles containing kaolin as a main component are used. showed that.
- the multilayer porous membranes of Examples 4-5 to 4-14 and Example 4-18 in which the porous layer using particles mainly composed of wax stone clay were formed were used in Examples 4-15 to 4-
- the heat shrinkage rate at 150 ° C. was as small as 5% or less in both the MD direction and the TD direction, indicating good heat shrinkage characteristics.
- the density of the porous layer is 0.7 to 0.95 cm 3 , which is significantly smaller than the multilayer porous film using particles containing kaolin having the same specific gravity as the main component, and the density of the porous film (0.8 g / cm 3 ) And a very small value of about 1.2 times. This value did not change even when the thickness of the porous layer was increased to about 10 ⁇ m.
- the air permeability of each of the multilayer porous membranes of Examples 4-5 to 4-14 and Example 4-18 was as small as 300 seconds / 100 CC or less.
- the rate of increase in air permeability was very small and could be suppressed to about 40% even when the thickness was about 10 ⁇ m. It was.
- the shutdown temperatures of the multilayer porous membranes or porous membranes of Examples 4-5 to 4-18 and Comparative Examples 4-3 to 4-6 were 145 to 148 ° C. and had a good shutdown function.
- the porous films of Comparative Examples 4-3 to 4-6 which did not form a porous layer, were short-circuited only by heating to the shutdown temperature + several degrees Celsius, but formed a porous layer composed of particles mainly composed of a waxy clay.
- the multilayer porous films of Examples 4-5 to 4-14, Examples 4-18, and Examples 4-15 to 4-17 in which the porous layer using particles containing kaolin as a main component were formed were all 200 ° C. or higher. Even if heated up to, it did not short-circuit and was very excellent in heat resistance.
- the simple batteries using the multilayer porous membranes or porous membranes of Examples 4-5 to 4-18 and Comparative Examples 4-3 to 4-6 as separators showed rate characteristics and cycle characteristics of 90% or more. . From this, it was confirmed that the multilayer porous membrane or the porous membrane produced in Examples 4-5 to 4-18 and Comparative Examples 4-3 to 4-6 can be used as a battery separator.
- the multilayer porous membrane of this embodiment is excellent in heat resistance, it can be suitably used for separation and purification of various substances at high temperatures. Moreover, since the multilayer porous film of this Embodiment has a shutdown function, it can be used especially suitably for a battery separator. In particular, it is suitable for a battery separator for a lithium ion secondary battery.
Abstract
Description
安全性の高い電池を製造することを目的として、特許文献1には、熱可塑性樹脂を主成分とする第一の多孔層に、耐熱層を積層してセパレータを形成する技術が記載されている。
また、使用する無機粒子によっては、無機粒子含有層自体の重量増加が無視できなくなる。特に、車載用途などの大型電池ではセパレータ使用量が格段に増加するため、その影響は大きくなる傾向にある。
本発明は、高温環境下においても熱収縮の抑制された多層多孔膜を提供することを目的とする。
また、本発明は、高温環境下においても熱収縮が抑制され、且つ軽量である多層多孔膜を提供することを目的とする。
また、無機粒子含有層を積層したポリオレフィン多孔膜においては、焼成カオリンを主成分とする粒子で無機粒子層を構成することにより、非常に軽量であり、しかも高温での熱収縮率が抑制された多層多孔膜を実現し得ることを見出した。
さらに、無機粒子含有層を積層したポリオレフィン多孔膜においては、ロウ石クレイを主成分とする粒子で無機粒子層を構成することにより、非常に軽量であり、しかも非常に薄い無機粒子層厚でも耐熱性が格段に向上し、高温での熱収縮率が著しく抑制されて、良好なシャットダウン機能を有しながらも200℃以上の高温においても短絡しないことを見出し、本発明に到達した。
[1]
ポリオレフィン樹脂を主成分とする多孔膜の少なくとも片面に、無機粒子と樹脂性バインダとを含む多孔層を備え、前記無機粒子がケイ酸アルミニウム化合物を主成分として含む多層多孔膜。
[2]
前記ケイ酸アルミニウム化合物が焼成カオリンである上記[1]記載の多層多孔膜。
[3]
前記ケイ酸アルミニウム化合物がロウ石クレイである上記[1]記載の多層多孔膜。
[4]
前記無機粒子の平均粒径が0.1μmを超え4.0μm以下である上記[1]~[3]のいずれか記載の多層多孔膜。
[5]
前記無機粒子において、0.2μmより大きく1.4μm以下の粒径を有する粒子が無機粒子全体に占める割合が2体積%以上である上記[1]~[4]のいずれか記載の多層多孔膜。
[6]
前記無機粒子において、0.2μmより大きく1.0μm以下の粒径を有する粒子が無機粒子全体に占める割合が1体積%以上である上記[5]記載の多層多孔膜。
[7]
前記無機粒子において、0.5μmより大きく2.0μm以下の粒径を有する粒子が無機粒子全体に占める割合が8体積%以上である上記[5]又は[6]記載の多層多孔膜。
[8]
前記無機粒子において、0.6μmより大きく1.4μm以下の粒径を有する粒子が無機粒子全体に占める割合が1体積%以上である上記[5]~[7]のいずれか記載の多層多孔膜。
[9]
前記無機粒子の前記多孔層中に占める割合(質量%)が、90%以上99%以下である上記[1]~[8]のいずれか記載の多層多孔膜。
[10]
前記樹脂性バインダがポリビニルアルコールである上記[1]~[9]のいずれか記載の多層多孔膜。
[11]
前記多孔膜が、ポリプロピレンと、ポリプロピレン以外のポリオレフィンを含む樹脂組成物からなる上記[1]~[10]のいずれか記載の多層多孔膜。
[12]
前記樹脂組成物中の総ポリオレフィンに対するポリプロピレンの割合が、1~35質量%である上記[11]記載の多層多孔膜。
[13]
上記[1]~[12]のいずれか記載の多層多孔膜からなる非水電解液電池用セパレータ。
[14]
上記[13]記載の非水電解液電池用セパレータと、正極と、負極と、電解液とを有する非水電解液電池。
前記無機粒子において、0.2μmより大きく1.0μm以下の粒径を有する粒子が無機粒子全体に占める割合としては、好ましくは1体積%以上、より好ましくは2体積%以上であり、好ましくは80体積%以下、より好ましくは70体積%以下である。
更に、前記無機粒子において、0.6μmより大きく1.4μm以下の粒径を有する粒子が無機粒子全体に占める割合としては、好ましくは1体積%以上、より好ましくは3体積%以上であり、好ましくは40体積%以下、より好ましくは30体積%以下である。
このような割合とすることは、より薄い多孔層厚の場合でも多孔膜の高温での熱収縮を抑制し、より優れた耐熱性を実現させる観点から好ましい。
ポリオレフィン樹脂を主成分とする多孔膜は、電池用セパレータとして用いた場合のシャットダウン性能などの点から、多孔膜を構成する樹脂成分の質量分率の50%以上100%以下をポリオレフィン樹脂が占めるポリオレフィン樹脂組成物からなる多孔膜であることが好ましい。ポリオレフィン樹脂が占める割合は60%以上100%以下がより好ましく、70%以上100%以下であることが更に好ましい。
また、多孔膜の耐熱性向上、多層多孔膜の耐熱性向上の観点からは、ポリプロピレンと、ポリプロピレン以外のポリオレフィン樹脂を含む樹脂組成物からなる多孔膜を用いることがより好ましい。
ポリオレフィン樹脂組成物中の総ポリオレフィンに対するポリプロピレンの割合は、耐熱性と良好なシャットダウン機能の両立の観点から、1~35質量%であることが好ましく、より好ましくは3~20質量%、さらに好ましくは4~10質量%である。
この場合、ポリプロピレン以外のポリオレフィン樹脂に限定はなく、例えば、エチレン、1-ブテン、4-メチル-1-ペンテン、1-ヘキセン、1-オクテン等のオレフィン炭化水素の単独重合体又は共重合体が挙げられる。具体的には、ポリエチレン、ポリブテン、エチレン-プロピレンランダム共重合体等が挙げられる。
これらの添加剤の総添加量は、ポリオレフィン樹脂組成物100質量部に対して、20質量部以下であることが好ましく、より好ましくは10質量部以下、さらに好ましくは5質量部以下である。
まず、ポリオレフィン樹脂組成物と可塑剤を溶融混練する。溶融混練方法としては、例えば、ポリオレフィン樹脂および必要によりその他の添加剤を、押出機、ニーダー、ラボプラストミル、混練ロール、バンバリーミキサー等の樹脂混練装置に投入し、樹脂成分を加熱溶融させながら任意の比率で可塑剤を導入して混練する方法が挙げられる。この際、ポリオレフィン樹脂、その他の添加剤及び可塑剤を樹脂混練装置に投入する前に、予めヘンシェルミキサー等を用い所定の割合で事前混練しておくことが好ましい。より好ましくは、事前混練において可塑剤の一部のみを投入し、残りの可塑剤を樹脂混練装置サイドフィードしながら混練することである。このようにすることにより、可塑剤の分散性を高め、後の工程で樹脂組成物と可塑剤の溶融混練合物のシート状成形体を延伸する際に、破膜することなく高倍率で延伸することができる。
なお、ここで、同時二軸延伸とは、MD方向(微多孔膜の機械方向)の延伸とTD方向(微多孔膜のMDを90°の角度で横切る方向)の延伸が同時に施される延伸方法をいい、各方向の延伸倍率は異なってもよい。逐次二軸延伸とは、MD方向、又はTD方向の延伸が独立して施される延伸方法をいい、MD方向又はTD方向に延伸がなされている際は、他方向は非拘束状態又は定長に固定されている状態とする。
本実施の形態の多層多孔膜は、耐熱性に優れ、シャットダウン機能を有しているので電池の中で正極と負極を隔離する電池用セパレータに適している。
特に、本実施の形態の多層多孔膜は高温においても短絡し難く、高起電力電池用のセパレータとしても安全に使用できる。
このような高起電力電池としては、例えば、非水電解液電池が挙げられ、本実施の形態の多層多孔膜を正極と負極の間に配置し、非水電解液を保持させることにより、非水電解液電池を製造することができる。
正極材料としては、例えば、LiCoO2、LiNiO2、スピネル型LiMnO4、オリビン型LiFePO4等のリチウム含有複合酸化物等が、負極材料としては、例えば、黒鉛質、難黒鉛化炭素質、易黒鉛化炭素質、複合炭素体等の炭素材料;シリコン、スズ、金属リチウム、各種合金材料等が挙げられる。
ショート温度は、ポリプロピレンの含有量や、ポリプロピレン以外のポリオレフィンの種類、無機粒子の種類、無機粒子含有層の厚さ等を調整することにより所望の値に制御することができる。
なお、上述した各種パラメータについては、特に断りのない限り、後述する実施例における測定法に準じて測定される。
(1)ポリオレフィンの粘度平均分子量(Mv)
ASTM-D4020に基づき、デカリン溶媒における135℃での極限粘度[η](dl/g)を求めた。
ポリエチレンについては、次式により算出した。
[η]=6.77×10-4Mv0.67
ポリプロピレンについては、次式によりMvを算出した。
[η]=1.10×10-4Mv0.80
多孔膜、多層多孔膜からMD10mm×TD10mmのサンプルを切り出し、格子状に9箇所(3点×3点)を選んで、膜厚をダイヤルゲージ(尾崎製作所製PEACOCK No.25(登録商標))を用いて測定し、9箇所の測定値の平均値を多孔膜、多層多孔膜の膜厚(μm)とした。また、このように測定された多層多孔膜と多孔膜の膜厚の差を多孔層の多孔層の層厚(μm)とした。
無機粒子を蒸留水に加え、ヘキサメタリン酸ナトリウム水溶液を少量添加してから超音波ホモジナイザで1分間分散させた後、レーザー式粒度分布測定装置(日機装(株)製マイクロトラックMT3300EX)を用いて粒径分布を測定した。累積頻度が50%となる粒径を平均粒径とした。
JIS P-8117準拠のガーレー式透気度計(東洋精機製G-B2(商標)、内筒質量:567g)を用い、645mm2の面積(直径28.6mmの円)の多孔膜、多層多孔膜を空気100ccが通過する時間(秒)を測定し、これを多孔膜、多層多孔膜の透気度とした。
多孔層の形成による透気度増加率は、以下の式にて算出した。
透気度増加率(%)={(多層多孔膜の透気度-多孔膜の透気度)/多孔膜の透気度}×100
セパレータをMD方向に100mm、TD方向に100mmに切り取り、150℃のオーブン中に1時間静置する。このとき、温風が直接サンプルにあたらないよう、サンプルを2枚の紙にはさむ。サンプルをオーブンから取り出し冷却した後、長さ(mm)を測定し、以下の式にてMDおよびTDの熱収縮率を算出した。
MD熱収縮率(%)=(100―加熱後のMDの長さ)/100×100
TD熱収縮率(%)=(100―加熱後のTDの長さ)/100×100
a.正極の作製
正極活物質としてリチウムコバルト複合酸化物(LiCoO2)を92.2質量部、導電材としてリン片状グラファイトとアセチレンブラックをそれぞれ2.3質量部、樹脂性バインダとしてポリフッ化ビニリデン(PVDF)を3.2質量部用意し、これらをN-メチルピロリドン(NMP)中に分散させてスラリーを調製した。このスラリーを正極集電体となる厚さ20μmのアルミニウム箔の片面にダイコーターを用いて、正極活物質塗布量が250g/m2となるように塗布した。130℃で3分間乾燥後、ロールプレス機を用いて、正極活物質かさ密度が3.00g/cm3となるように圧縮成形し、正極とした。
負極活物質として人造グラファイトを96.6質量部、樹脂性バインダとしてカルボキシメチルセルロースのアンモニウム塩1.4質量部とスチレン-ブタジエン共重合体ラテックス1.7質量部を用意し、これらを精製水中に分散させてスラリーを調製した。このスラリーを負極集電体となる厚さ12μmの銅箔の片面にダイコーターを用いて負極活物質塗布量が106g/m2となるように塗布した。120℃で3分間乾燥後、ロールプレス機を用いて、負極活物質かさ密度が1.35g/cm3となるように圧縮成形し、負極とした。
プロピレンカーボネート:エチレンカーボネート:γ-ブチルラクトン=1:1:2(体積比)の混合溶媒に、溶質としてLiBF4を濃度1.0mol/Lとなるように溶解させ、非水電解液を調製した。
65mm×20mmに切り出して非水電解液に1分以上浸漬した負極、中央部に直径16mmの穴をあけた9μm(厚さ)×50mm×50mmのアラミドフィルム、65mm×20mmに切り出して非水電解液に1時間以上浸漬した多層多孔膜または多孔膜、65mm×20mmに切り出して非水電解液に1分以上浸漬した正極、カプトンフィルム、厚さ約4mmのシリコンゴムを用意し、熱電対を接続したセラミックプレート上に、この順で積層した。この積層体をホットプレート上にセットし、油圧プレス機にて4.1MPaの圧力をかけた状態で15℃/minの速度で昇温し、正負極間のインピーダンス変化を交流1V、1kHzの条件下で200℃まで測定した。
インピーダンスが1000Ωに達した時点の温度をシャットダウン温度とし、シャットダウン後、再びインピーダンスが1000Ωを下回った時点の温度をショート温度とした。
a.正極の作製
(6)のaと同様にして作製した正極を面積2.00cm2の円形に打ち抜いた。
b.負極の作製
(6)のbと同様にして作製した負極を面積2.05cm2の円形に打ち抜いた。
c.非水電解液
エチレンカーボネート:エチルメチルカーボネート=1:2(体積比)の混合溶媒に、溶質としてLiPF6を濃度1.0ml/Lとなるように溶解させて調製した。
d.電池組立
正極と負極の活物質面が対向するように、下から負極、多層多孔膜、正極の順に重ねた。この積層体を、容器本体と蓋が絶縁されている蓋付きステンレス金属製容器に、負極の銅箔、正極のアルミ箔が、それぞれ、容器本体、蓋と接するように収納した。この容器内に、非水電解液を注入して密閉した。
(レート特性)
d.で組み立てた簡易電池を、25℃において、電流値3mA(約0.5C)で電池電圧4.2Vまで充電し、さらに4.2Vを保持するようにして電流値を3mAから絞り始めるという方法で、合計約6時間、電池作成後の最初の充電を行い、その後電流値3mAで電池電圧3.0Vまで放電した。
次に、25℃において、電流値6mA(約1.0C)で電池電圧4.2Vまで充電し、さらに4.2Vを保持するようにして電流値を6mAから絞り始めるという方法で、合計約3時間充電を行い、その後電流値6mAで電池電圧3.0Vまで放電して、その時の放電容量を1C放電容量(mAh)とした。
次に、25℃において、電流値6mA(約1.0C)で電池電圧4.2Vまで充電し、さらに4.2Vを保持するようにして電流値を6mAから絞り始めるという方法で、合計約3時間充電を行い、その後電流値12mA(約2.0C)で電池電圧3.0Vまで放電して、その時の放電容量を2C放電容量(mAh)とした。
1C放電容量に対する2C放電容量の割合を算出し、この値をレート特性とした。
レート特性(%)=(2C放電容量/1C放電容量)×100
レート特性を評価した簡易電池を、60℃において、電流値6mA(約1.0C)で電池電圧4.2Vまで充電し、さらに4.2Vを保持するようにして電流値を6mAから絞り始めるという方法で、合計約3時間充電を行い、そして電流値6mAで電池電圧3.0Vまで放電するというサイクルを100回繰り返し、1サイクル目と100サイクル目の放電容量(mAh)を測定した。
1回目の放電容量に対する100サイクル目の放電容量の割合を算出し、この値をサイクル特性とした。
サイクル特性(%)=(100回目の放電容量/1回目の放電容量)×100
10cm×10cm角の試料を微多孔膜から切り取り、その体積(cm3)と質量(g)を求め、膜密度を0.95(g/cm3)として次式を用いて計算した。
気孔率=(1-質量/体積/0.95)×100
多孔膜、多層多孔膜からMD100mm×TD100mmのサンプルを各3箇所ずつ切り出し、電子天秤を用いてそれぞれの重量を測定し、各々3枚の平均値を多孔膜、多層多孔膜の目付(g/100cm2)とした。また、このように測定された多層多孔膜と多孔膜の目付の差を多孔層の目付(g/100cm2)とした。多孔層の層密度は、以下の式にて算出した。
多孔層の層密度(g/cm3)=多孔層の目付(g/100cm2)/多孔層の層厚(μm)×100
測定用アルミパンに、無機粒子5mgとエチレンカーボネート:エチルメチルカーボネート=1:2(体積比)の混合溶媒に、溶質としてLiPF6を濃度1.0ml/Lとなるように溶解させて調製した非水電解液5mgを加え、ふたをしてから、かしめ機にて密閉する。これを示唆熱分析測定装置(SIIナノテクノロジー社製DSC210)に設置し、10℃/分で室温から200℃まで昇温し、反応熱ピークの有無を測定した。
無機粒子を20mmφアルミリングに詰めて錠剤成型した後、蛍光X線測定装置(リガク製ZSX-100e(Rh管球))を用いて、全元素定性分析を行い、ピーク強度から各元素の含有率を半定量的に算出し、組成を求めた。
無機粒子を深さ2mmのアルミ製ホルダに充填後、X線回折測定装置(リガク製Rint-2500(Cu管球))を用いて、測定範囲5~80度、スキャンスピード4度/分でX線回折パターンを測定した。
カオリン1、2、3、5:カオリナイト(Al2Si2O5(OH)4)を主成分とするアルミノケイ酸塩鉱物。
カオリン4:パイロフィライト(Al2Si4O10(OH)2)を主成分とするアルミノケイ酸塩鉱物。
カオリン6、7:カオリン4をビーズミルにて湿式粉砕したもの。
焼成カオリン1:カオリナイトを主成分とするカオリンを高温焼成処理したもの。
焼成カオリン2:焼成カオリン1をビーズミルにて湿式粉砕したもの。
合成ケイ酸アルミニウム1:化学合成したケイ酸アルミニウム。
合成ケイ酸アルミニウム2、3:合成ケイ酸アルミニウム1をビーズミルにて湿式粉砕したもの。
なお、各粒子の粒径分布および平均粒径を表1に示す。
Mv70万のホモポリマーのポリエチレン47質量部とMv25万のホモポリマーのポリエチレン46質量部とMv40万のホモポリマーのポリプロピレン7質量部とを、タンブラーブレンダーを用いてドライブレンドした。得られた純ポリマー混合物99質量%に、酸化防止剤としてペンタエリスリチル-テトラキス-[3-(3,5-ジ-t-ブチル-4-ヒドロキシフェニル)プロピオネート]を1質量%添加し、再度タンブラーブレンダーを用いてドライブレンドすることにより、ポリマー等混合物を得た。得られたポリマー等混合物は窒素で置換を行った後に、二軸押出機へ窒素雰囲気下でフィーダーにより供給した。また、可塑剤として流動パラフィン(37.78℃における動粘度7.59×10-5m2/s)を押出機シリンダーにプランジャーポンプにより注入した。溶融混練し、押し出される全混合物中に占める流動パラフィン量比が65質量%となるように、フィーダーおよびポンプを調整した。溶融混練条件は、設定温度200℃、スクリュー回転数240rpm、吐出量12kg/hで行った。
続いて、溶融混練物を、Tダイを経て表面温度25℃に制御された冷却ロール上に押出しキャストすることにより、厚さ2000μmのシート状のポリオレフィン組成物を得た。
さらにTDテンター熱固定機に導き、熱固定を行った。熱固定温度は133℃、TD緩和率0.80とした。その結果、膜厚16μm、気孔率40%、透気度160秒/100ccのポリオレフィン樹脂多孔膜を得た。
表1のカオリン2を用い、多孔層の厚さを3μmとした以外は、実施例1-1と同様にして多層多孔膜を得た。
表1のカオリン3を用いた以外は、実施例1-1と同様にして多層多孔膜を得た。
表1のカオリン7を97.5重量部とポリビニルアルコール(平均重合度1700、ケン化度99%以上)2.5重量部とを150重量部の水に均一に分散させて塗布液を調製し、ポリオレフィン樹脂多孔膜上に厚さ5μmの多孔層を形成した以外は、実施例1-1と同様にして多層多孔膜を得た。
表1の焼成カオリン1を97.0重量部とポリビニルアルコール(平均重合度1700、ケン化度99%以上)3.0重量部とを150重量部の水に均一に分散させて塗布液を調製した以外は、実施例1-1と同様にして多層多孔膜を得た。
表1の焼成カオリン2を用いた以外は、実施例1-1と同様にして多層多孔膜を得た。
表1の焼成カオリン2を95.0質量部とアクリルラテックス(AclLTX,固形分濃度40%、平均粒径90nm、最低成膜温度0℃以下)5.0質量部、ポリカルボン酸アンモニウム水溶液(サンノプコ製SNディスパーサント5468)1重量部、ポリオキシアルキレン系界面活性剤(サンノプコ製SNウェット980)1重量部を150質量部の水に均一に分散させて塗布液を調製し、ポリオレフィン樹脂多孔膜上に厚さ6μmの多孔層を形成した以外は、実施例1-1と同様にして多層多孔膜を得た。
Mv70万のホモポリマーのポリエチレン47.5質量部とMv25万のホモポリマーのポリエチレン47.5質量部とMv40万のホモポリマーのポリプロピレン5質量部とを、タンブラーブレンダーを用いてドライブレンドした。得られた純ポリマー混合物99質量%に、酸化防止剤としてペンタエリスリチル-テトラキス-[3-(3,5-ジ-t-ブチル-4-ヒドロキシフェニル)プロピオネート]を1質量%添加し、再度タンブラーブレンダーを用いてドライブレンドすることにより、ポリマー等混合物を得た。得られたポリマー等混合物は窒素で置換を行った後に、二軸押出機へ窒素雰囲気下でフィーダーにより供給した。また、可塑剤として流動パラフィン(37.78℃における動粘度7.59×10-5m2/s)を押出機シリンダーにプランジャーポンプにより注入した。溶融混練し、押し出される全混合物中に占める流動パラフィン量比が65質量%となるように、フィーダーおよびポンプを調整した。溶融混練条件は、設定温度200℃、スクリュー回転数240rpm、吐出量12kg/hで行った。
続いて、溶融混練物を、Tダイを経て表面温度25℃に制御された冷却ロール上に押出しキャストすることにより、厚さ1300μmのシート状のポリオレフィン組成物を得た。
さらにTDテンター熱固定機に導き、熱固定を行った。熱固定温度は122℃、TD緩和率0.80とした。その結果、膜厚16μm、気孔率49%、透気度155秒/100ccのポリオレフィン樹脂多孔膜を得た。
表1の焼成カオリン2を98.2質量部とポリビニルアルコール(平均重合度1700、ケン化度99%以上)1.8質量部とを150質量部の水に均一に分散させて塗布液を調製し、上記ポリオレフィン樹脂多孔膜の表面にグラビアコーターを用いて塗布した。60℃にて乾燥して水を除去し、ポリオレフィン樹脂多孔膜上に厚さ5μmの多孔層を形成した多層多孔膜を得た。
多孔膜の膜厚を12μm、気孔率を40%、透気度を120秒/100ccとしたこと以外は、実施例1-6と同様にして多層多孔膜を得た。
表1の焼成カオリン2を97.0重量部とポリビニルアルコール(平均重合度1700、ケン化度99%以上)3.0重量部とを150重量部の水に均一に分散させて塗布液を調製した以外は、実施例1-9と同様にして多層多孔膜を得た。
多孔膜の膜厚を20μm、気孔率を40%、透気度を280秒/100ccとしたことと、多孔層の厚さを7μmとした以外は、実施例1-10と同様にして多層多孔膜を得た。
表1の合成ケイ酸アルミニウム2を97.5重量部とポリビニルアルコール(平均重合度1700、ケン化度99%以上)2.5重量部とを150重量部の水に均一に分散させて塗布液を調製し、ポリオレフィン樹脂多孔膜上に厚さ6μmの多孔層を形成した以外は、実施例1-1と同様にして多層多孔膜を得た。
表1の合成ケイ酸アルミニウム3を用いた以外は、実施例1-12と同様にして多層多孔膜を得た。
表1のカオリン7を95.0重量部とポリビニルアルコール(平均重合度1700、ケン化度99%以上)5.0重量部とを150重量部の水に均一に分散させて塗布液を調製し、ポリオレフィン樹脂多孔膜上に厚さ5μmの多孔層を形成した以外は、実施例1-9と同様にして多層多孔膜を得た。
表1のカオリン4を97.5重量部とポリビニルアルコール(平均重合度1700、ケン化度99%以上)2.5重量部とを150重量部の水に均一に分散させて塗布液を調製し、ポリオレフィン樹脂多孔膜上に厚さ7μmの多孔層を形成した以外は、実施例1-1と同様にして多層多孔膜を得た。
表1のカオリン5を用いて、ポリオレフィン樹脂多孔膜上に厚さ7μmの多孔層を形成した以外は、実施例1-1と同様にして多層多孔膜を得た。
表1のカオリン6を用いた以外は、実施例1-15と同様にして多層多孔膜を得た。
表1の合成ケイ酸アルミニウム1を用いて、ポリオレフィン樹脂多孔膜上に厚さ10μmの多孔層を形成した以外は、実施例1-15と同様にして多層多孔膜を得た。
ポリオレフィン樹脂多孔膜上の片面に厚さ3μmの多孔層を形成してから、さらに同じポリオレフィン樹脂多孔膜上の他方の面に厚さ3μmの多孔層を形成することで、ポリオレフィン樹脂多孔膜の両面に各3μm、合計6μmの多孔層を形成した以外は、実施例1-7と同様にして多層多孔膜を得た。
多孔層を形成しなかった以外は実施例1-1と同様にして多孔膜を得た。
多孔層を形成しなかった以外は実施例1-8と同様にして多孔膜を得た。
多孔層を形成しなかった以外は実施例1-9と同様にして多孔膜を得た。
多孔層を形成しなかった以外は実施例1-11と同様にして多孔膜を得た。
多孔層を形成しなかった比較例1-1~1-4の多孔膜は、150℃での熱収縮率が50%を超える非常に大きな値を示した。
これに対し、粒子全体の2%以上が粒径0.2μmより大きく1.4μm以下であるケイ酸アルミニウム化合物を主成分とする粒子を使用した多孔層を形成した実施例1-1~1-14、実施例1-19の多層多孔膜は、アルミナ多孔層の厚さが3~7μmと薄いにもかかわらず、150℃での熱収縮率がMD方向、TD方向のいずれも5%以下と非常に小さく、良好な耐熱収縮特性を示した。
実施例1-1~1-14、1-19の多層多孔膜の透気度はいずれも300秒/100CC以下と小さかった。特に、多孔層を形成しなかった比較例1-1~1-4の多孔膜と比較しても、透気度上昇率を100%以下に抑えることができた。
カオリン1、2、3、5、8:カオリナイト(Al2Si2O5(OH)4)を主成分とするアルミノケイ酸塩鉱物。
カオリン4、6、7:パイロフィライト(Al2Si4O10(OH)2)を主成分とするアルミノケイ酸塩鉱物。なお、カオリン4、6はカオリン7をビーズミルにて湿式粉砕したものである。
焼成カオリン1、2:カオリナイトを主成分とするカオリンを高温焼成処理したもの。なお、焼成カオリン1は焼成カオリン2をビーズミルにて湿式粉砕したものである。
合成ケイ酸アルミニウム1、2、3:化学合成したケイ酸アルミニウム。なお、合成ケイ酸アルミニウム1、2は合成ケイ酸アルミニウム3をビーズミルにて湿式粉砕したものである。
なお、各粒子の平均粒径を表3に示す。
Mv70万のホモポリマーのポリエチレン47質量部とMv25万のホモポリマーのポリエチレン46質量部とMv40万のホモポリマーのポリプロピレン7質量部とを、タンブラーブレンダーを用いてドライブレンドした。得られた純ポリマー混合物99質量%に、酸化防止剤としてペンタエリスリチル-テトラキス-[3-(3,5-ジ-t-ブチル-4-ヒドロキシフェニル)プロピオネート]を1質量%添加し、再度タンブラーブレンダーを用いてドライブレンドすることにより、ポリマー等混合物を得た。得られたポリマー等混合物は窒素で置換を行った後に、二軸押出機へ窒素雰囲気下でフィーダーにより供給した。また、可塑剤として流動パラフィン(37.78℃における動粘度7.59×10-5m2/s)を押出機シリンダーにプランジャーポンプにより注入した。溶融混練し、押し出される全混合物中に占める流動パラフィン量比が65質量%となるように、フィーダーおよびポンプを調整した。溶融混練条件は、設定温度200℃、スクリュー回転数240rpm、吐出量12kg/hで行った。
次に同時二軸テンター延伸機へ導き、MD方向に7倍、TD方向に7倍に同時二軸延伸を行った。この時、同時二軸テンターの設定温度は125℃であった。次にメチルエチルケトン槽に導き、流動パラフィンを抽出除去した後、メチルエチルケトンを乾燥除去した。
さらにTDテンター熱固定機に導き、熱固定を行った。熱固定温度は133℃、TD緩和率0.80とした。その結果、膜厚16μm、気孔率40%、透気度160秒/100ccのポリオレフィン樹脂多孔膜を得た。
カオリン2を用い、多孔層の厚さを4μmとした以外は、実施例2-1と同様にして多層多孔膜を得た。
合成ケイ酸アルミニウム1を97.0重量部とポリビニルアルコール(平均重合度1700、ケン化度99%以上)3.0重量部とを150重量部の水に均一に分散させて塗布液を調製し、ポリオレフィン樹脂多孔膜上に厚さ6μmの多孔層を形成した以外は、実施例2-1と同様にして多層多孔膜を得た。
焼成カオリン1を97.5重量部とポリビニルアルコール(平均重合度1700、ケン化度99%以上)2.5重量部とを150重量部の水に均一に分散させて塗布液を調製した以外は、実施例2-2と同様にして多層多孔膜を得た。
カオリン3を用いた以外は、実施例2-2と同様にして多層多孔膜を得た。
焼成カオリン2を用い、多孔層の厚さを5μmとした以外は、実施例2-3と同様にして多層多孔膜を得た。
カオリン4を用い、多孔層の厚さを6μmとした以外は、実施例2-4と同様にして多層多孔膜を得た。
カオリン5を用いた以外は、実施例2-1と同様にして多層多孔膜を得た。
焼成カオリン1を95.0質量部とアクリルラテックス(以下、「Acl」と略記することがある。固形分濃度40%、平均粒径90nm、最低成膜温度0℃以下)5.0質量部、ポリカルボン酸アンモニウム水溶液(サンノプコ製SNディスパーサント5468)1重量部、ポリオキシアルキレン系界面活性剤(サンノプコ製SNウェット980)1重量部を150質量部の水に均一に分散させて塗布液を調製し、ポリオレフィン樹脂多孔膜上に厚さ7μmの多孔層を形成した以外は、実施例2-1と同様にして多層多孔膜を得た。
Mv70万のホモポリマーのポリエチレン47.5質量部とMv25万のホモポリマーのポリエチレン47.5質量部とMv40万のホモポリマーのポリプロピレン5質量部とを、タンブラーブレンダーを用いてドライブレンドした。得られた純ポリマー混合物99質量%に、酸化防止剤としてペンタエリスリチル-テトラキス-[3-(3,5-ジ-t-ブチル-4-ヒドロキシフェニル)プロピオネート]を1質量%添加し、再度タンブラーブレンダーを用いてドライブレンドすることにより、ポリマー等混合物を得た。得られたポリマー等混合物は窒素で置換を行った後に、二軸押出機へ窒素雰囲気下でフィーダーにより供給した。また、可塑剤として流動パラフィン(37.78℃における動粘度7.59×10-5m2/s)を押出機シリンダーにプランジャーポンプにより注入した。溶融混練し、押し出される全混合物中に占める流動パラフィン量比が65質量%となるように、フィーダーおよびポンプを調整した。溶融混練条件は、設定温度200℃、スクリュー回転数240rpm、吐出量12kg/hで行った。
次に同時二軸テンター延伸機へ導き、MD方向に7倍、TD方向に6.4倍に同時二軸延伸を行った。この時、同時二軸テンターの設定温度は118℃であった。次にメチルエチルケトン槽に導き、流動パラフィンを抽出除去した後、メチルエチルケトンを乾燥除去した。
さらにTDテンター熱固定機に導き、熱固定を行った。熱固定温度は122℃、TD緩和率0.80とした。その結果、膜厚16μm、気孔率49%、透気度155秒/100ccのポリオレフィン樹脂多孔膜を得た。
多孔膜の膜厚を12μm、気孔率を40%、透気度を120秒/100ccとしたこと以外は、実施例2-1と同様にして多層多孔膜を得た。
焼成カオリン1を97.0重量部とポリビニルアルコール(平均重合度1700、ケン化度99%以上)3.0重量部とを150重量部の水に均一に分散させて塗布液を調製した以外は、実施例2-11と同様にして多層多孔膜を得た。
多孔膜の膜厚を20μm、気孔率を40%、透気度を280秒/100ccとしたことと、焼成カオリン1を96.5重量部とポリビニルアルコール(平均重合度1700、ケン化度99%以上)3.5重量部とを150重量部の水に均一に分散させて塗布液を調製し、ポリオレフィン樹脂多孔膜上に厚さ6μmの多孔層を形成した以外は、実施例2-1と同様にして多層多孔膜を得た。
カオリン4を96.0重量部とポリビニルアルコール(平均重合度1700、ケン化度99%以上)4.0重量部とを150重量部の水に均一に分散させて塗布液を調製し、ポリオレフィン樹脂多孔膜上に厚さ4μmの多孔層を形成した以外は、実施例2-11と同様にして多層多孔膜を得た。
カオリン6を用いて、ポリオレフィン樹脂多孔膜上に厚さ7μmの多孔層を形成した以外は、実施例2-4と同様にして多層多孔膜を得た。
カオリン7を用いた以外は、実施例2-15と同様にして多層多孔膜を得た。
カオリン8を用いて、ポリオレフィン樹脂多孔膜上に厚さ7μmの多孔層を形成した以外は、実施例2-1と同様にして多層多孔膜を得た。
合成ケイ酸アルミニウム2を用いて、ポリオレフィン樹脂多孔膜上に厚さ7μmの多孔層を形成した以外は、実施例2-3と同様にして多層多孔膜を得た。
合成ケイ酸アルミニウム3を用いて、ポリオレフィン樹脂多孔膜上に厚さ10μmの多孔層を形成した以外は、実施例2-4と同様にして多層多孔膜を得た。
ポリオレフィン樹脂多孔膜上の片面に厚さ3μmの多孔層を形成してから、さらに同じポリオレフィン樹脂多孔膜上の他方の面に厚さ4μmの多孔層を形成することで、ポリオレフィン樹脂多孔膜の両面に合計7μmの多孔層を形成した以外は、実施例2-9と同様にして多層多孔膜を得た。
多孔層を形成しなかった以外は実施例2-1と同様にして多孔膜を得た。
多孔層を形成しなかった以外は実施例2-10と同様にして多孔膜を得た。
多孔層を形成しなかった以外は実施例2-11と同様にして多孔膜を得た。
多孔層を形成しなかった以外は実施例2-13と同様にして多孔膜を得た。
多孔層を形成しなかった比較例2-1~2-4の多孔膜は、150℃での熱収縮率が50%を超える非常に大きな値を示した。
一方、平均粒径0.1μm未満または4.0μmより大きいケイ酸アルミニウム化合物を主成分とする粒子を使用した多孔層を形成した実施例2-15~2-19の多層多孔膜は、多孔層を形成しなかった比較例2-1~2-4の多孔膜と比較すると150℃での熱収縮率は抑制されたが、多孔層の厚さが7μm以上あっても、MD方向で10%以上、TD方向でも10%以上の値であった。
実施例2-1~2-20、比較例2-1~2-4の多層多孔膜又は多孔膜のシャットダウン温度は145~148℃であり、良好なシャットダウン機能を有するものであった。多孔層を形成しなかった比較例2-1~2-4の多孔膜は、シャットダウン温度+数℃まで加熱しただけで短絡したが、ケイ酸アルミニウム化合物を主成分とする粒子からなる多孔層を形成した実施例2-1~2-20の多層多孔膜は全て200℃以上まで加熱しても短絡せず、耐熱性に非常に優れていた。
実施例2-1~2-20、比較例2-1~2-4の多層多孔膜又は多孔膜をセパレータとして用いた簡易電池は、いずれも、90%以上のレート特性、サイクル特性を示した。このことから、実施例2-1~2-20、比較例2-1~2-4で製造した多層多孔膜又は多孔膜は、電池用セパレータとして使用可能なものであることが確認できた。
実施例3-6~3-21、比較例3-3~3-8において使用した無機粒子は、下記のケイ酸アルミニウム化合物を主成分とする粒子とシリカ、アルミナである。
焼成カオリン1、2:カオリナイト(Al2Si2O5(OH)4)を主成分とするカオリンを高温焼成処理したもの。
カオリン1、2:カオリナイト(Al2Si2O5(OH)4)を主成分とするアルミノケイ酸塩鉱物。
合成ケイ酸アルミニウム:化学合成したケイ酸アルミニウム。
ケイ酸アルミニウム化合物の中で、焼成カオリンは電解液との反応熱によるピークが確認されず、化学的に非常に安定であることが知られている、アルミナと同等の結果が得られた。
Mv70万のホモポリマーのポリエチレン47質量部とMv25万のホモポリマーのポリエチレン46質量部とMv40万のホモポリマーのポリプロピレン7質量部とを、タンブラーブレンダーを用いてドライブレンドした。得られた純ポリマー混合物99質量%に、酸化防止剤としてペンタエリスリチル-テトラキス-[3-(3,5-ジ-t-ブチル-4-ヒドロキシフェニル)プロピオネート]を1質量%添加し、再度タンブラーブレンダーを用いてドライブレンドすることにより、ポリマー等混合物を得た。得られたポリマー等混合物は窒素で置換を行った後に、二軸押出機へ窒素雰囲気下でフィーダーにより供給した。また、可塑剤として流動パラフィン(37.78℃における動粘度7.59×10-5m2/s)を押出機シリンダーにプランジャーポンプにより注入した。溶融混練し、押し出される全混合物中に占める流動パラフィン量比が65質量%となるように、フィーダーおよびポンプを調整した。溶融混練条件は、設定温度200℃、スクリュー回転数240rpm、吐出量12kg/hで行った。
次に同時二軸テンター延伸機へ導き、MD方向に7倍、TD方向に7倍に同時二軸延伸を行った。この時、同時二軸テンターの設定温度は125℃であった。次にメチルエチルケトン槽に導き、流動パラフィンを抽出除去した後、メチルエチルケトンを乾燥除去した。
さらにTDテンター熱固定機に導き、熱固定を行った。熱固定温度は133℃、TD緩和率0.80とした。その結果、膜厚16μm、気孔率40%、透気度160秒/100ccのポリオレフィン樹脂多孔膜を得た。
焼成カオリン1を96.5重量部とポリビニルアルコール(平均重合度1700、ケン化度99%以上)3.5重量部とを150重量部の水に均一に分散させて塗布液を調製し、ポリオレフィン樹脂多孔膜上に厚さ5μmの多孔層を形成した以外は、実施例3-6と同様にして多層多孔膜を得た。
焼成カオリン1をビーズミルにて湿式粉砕した焼成カオリン3を用いた以外は、実施例3-6と同様にして多層多孔膜を得た。
焼成カオリン3を97.0重量部とポリビニルアルコール(平均重合度1700、ケン化度99%以上)3.0重量部とを150重量部の水に均一に分散させて塗布液を調製し、ポリオレフィン樹脂多孔膜上に厚さ5μmの多孔層を形成した以外は、実施例3-6と同様にして多層多孔膜を得た。
焼成カオリン3を94.0質量部とアクリルラテックス(固形分濃度40%、平均粒径90nm、最低成膜温度0℃以下)6.0質量部、ポリカルボン酸アンモニウム水溶液(サンノプコ製SNディスパーサント5468)1重量部、ポリオキシアルキレン系界面活性剤(サンノプコ製SNウェット980)1重量部を150質量部の水に均一に分散させて塗布液を調製し、ポリオレフィン樹脂多孔膜上に厚さ6μmの多孔層を形成した以外は、実施例3-6と同様にして多層多孔膜を得た。
焼成カオリン3を98.2重量部とポリビニルアルコール(平均重合度1700、ケン化度99%以上)1.8重量部とを150重量部の水に均一に分散させて塗布液を調製し、ポリオレフィン樹脂多孔膜上に厚さ7μmの多孔層を形成した以外は、実施例3-6と同様にして多層多孔膜を得た。
ポリオレフィン樹脂多孔膜上に厚さ8μmの多孔層を形成した以外は、実施例3-9と同様にして多層多孔膜を得た。
ポリオレフィン樹脂多孔膜上に厚さ10μmの多孔層を形成した以外は、実施例3-8と同様にして多層多孔膜を得た。
(多孔膜の製造)
Mv70万のホモポリマーのポリエチレン47.5質量部とMv25万のホモポリマーのポリエチレン47.5質量部とMv40万のホモポリマーのポリプロピレン5質量部とを、タンブラーブレンダーを用いてドライブレンドした。得られた純ポリマー混合物99質量%に、酸化防止剤としてペンタエリスリチル-テトラキス-[3-(3,5-ジ-t-ブチル-4-ヒドロキシフェニル)プロピオネート]を1質量%添加し、再度タンブラーブレンダーを用いてドライブレンドすることにより、ポリマー等混合物を得た。得られたポリマー等混合物は窒素で置換を行った後に、二軸押出機へ窒素雰囲気下でフィーダーにより供給した。また、可塑剤として流動パラフィン(37.78℃における動粘度7.59×10-5m2/s)を押出機シリンダーにプランジャーポンプにより注入した。溶融混練し、押し出される全混合物中に占める流動パラフィン量比が65質量%となるように、フィーダーおよびポンプを調整した。溶融混練条件は、設定温度200℃、スクリュー回転数240rpm、吐出量12kg/hで行った。
次に同時二軸テンター延伸機へ導き、MD方向に7倍、TD方向に6.4倍に同時二軸延伸を行った。この時、同時二軸テンターの設定温度は118℃であった。次にメチルエチルケトン槽に導き、流動パラフィンを抽出除去した後、メチルエチルケトンを乾燥除去した。
次に、焼成カオリン3を98.0質量部とポリビニルアルコール(平均重合度1700、ケン化度99%以上)2.0質量部とを150質量部の水に均一に分散させて塗布液を調製し、上記ポリオレフィン樹脂多孔膜の表面にグラビアコーターを用いて塗布した。60℃にて乾燥して水を除去し、ポリオレフィン樹脂多孔膜上に厚さ5μmの多孔層を形成した多層多孔膜を得た。
多孔膜の膜厚を12μm、気孔率を40%、透気度を120秒/100ccとしたことと、焼成カオリン3を97.5重量部とポリビニルアルコール(平均重合度1700、ケン化度99%以上)2.5重量部とを150重量部の水に均一に分散させて塗布液を調製し、ポリオレフィン樹脂多孔膜上に厚さ3μmの多孔層を形成した以外は、実施例3-6と同様にして多層多孔膜を得た。
多孔膜の膜厚を12μm、気孔率を40%、透気度を120秒/100ccとした以外は、実施例3-9と同様にして多層多孔膜を得た。
多孔膜の膜厚を20μm、気孔率を40%、透気度を280秒/100ccとしたことと、焼成カオリン3を96.0重量部とポリビニルアルコール(平均重合度1700、ケン化度99%以上)4.0重量部とを150重量部の水に均一に分散させて塗布液を調製し、ポリオレフィン樹脂多孔膜上に厚さ7μmの多孔層を形成した以外は、実施例3-6と同様にして多層多孔膜を得た。
カオリン1を用いて、ポリオレフィン樹脂多孔膜上に厚さ4μmの多孔層を形成した以外は、実施例3-11と同様にして多層多孔膜を得た。
ポリオレフィン樹脂多孔膜上に厚さ7μmの多孔層を形成した以外は、実施例3-18と同様にして多層多孔膜を得た。
カオリン2を用いて、ポリオレフィン樹脂多孔膜上に厚さ6μmの多孔層を形成した以外は、実施例3-18と同様にして多層多孔膜を得た。
ポリオレフィン樹脂多孔膜上の片面に厚さ4μmの多孔層を形成してから、さらに同じポリオレフィン樹脂多孔膜上の他方の面に厚さ4μmの多孔層を形成することで、ポリオレフィン樹脂多孔膜の両面に各4μm、合計8μmの多孔層を形成した以外は、実施例3-10と同様にして多層多孔膜を得た。
アルミナを用いた以外は、実施例3-18と同様にして多層多孔膜を得た。
ポリオレフィン樹脂多孔膜上に厚さ7μmの多孔層を形成した以外は、比較例3-3と同様にして多層多孔膜を得た。
多孔層を形成しなかった以外は実施例3-6と同様にして多孔膜を得た。
多孔層を形成しなかった以外は実施例3-14と同様にして多孔膜を得た。
多孔層を形成しなかった以外は実施例3-15と同様にして多孔膜を得た。
多孔層を形成しなかった以外は実施例3-17と同様にして多孔膜を得た。
多孔層を形成しなかった比較例3-5~3-8の多孔膜は、150℃での熱収縮率が50%を超える非常に大きな値を示した。
一方、カオリンあるいはアルミナを主成分とする粒子を使用した多孔層を形成した比較例3-3~3-4の多層多孔膜は、多孔層の厚さが4~7μmと薄いにもかかわらず、150℃での熱収縮率がMD方向、TD方向のいずれも5%以下と非常に小さく、良好な耐熱収縮特性を示した。しかし、多孔層の密度は、カオリンを主成分とする粒子を使用した場合、1.3~1.5g/cm3、比重が大きいアルミナを主成分とする粒子を使用した場合は1.7g/cm3と、多孔膜の密度(0.8g/cm3)の1.6~2倍の値を示した。
実施例4-5~4-18、比較例4-3~4-6において使用した無機粒子は、下記のケイ酸アルミニウム化合物を主成分とする粒子とシリカ、アルミナである。
ロウ石クレイ:パイロフィライト(Al2Si4O10(OH)2)を主成分とするアルミノケイ酸塩鉱物。今回は局方グレード品を用いた。
カオリン1、2:カオリナイト(Al2Si2O5(OH)4)を主成分とするアルミノケイ酸塩鉱物。
合成ケイ酸アルミニウム:化学合成したケイ酸アルミニウム。
今回使用した無機粒子の平均粒径、組成、X線回折パターンと共に、電解液との反応熱の有無を表6に示す。ロウ石クレイのSi、Oの含有率が多いが、X線回折パターンからは石英を不純物として含んでいることが確認された。
ケイ酸アルミニウム化合物の中で、ロウ石クレイは電解液との反応熱によるピークが確認されず、化学的に非常に安定であることが知られている、アルミナと同等の結果が得られた。
(多孔膜の製造)
Mv70万のホモポリマーのポリエチレン47質量部とMv25万のホモポリマーのポリエチレン46質量部とMv40万のホモポリマーのポリプロピレン7質量部とを、タンブラーブレンダーを用いてドライブレンドした。得られた純ポリマー混合物99質量%に、酸化防止剤としてペンタエリスリチル-テトラキス-[3-(3,5-ジ-t-ブチル-4-ヒドロキシフェニル)プロピオネート]を1質量%添加し、再度タンブラーブレンダーを用いてドライブレンドすることにより、ポリマー等混合物を得た。得られたポリマー等混合物は窒素で置換を行った後に、二軸押出機へ窒素雰囲気下でフィーダーにより供給した。また、可塑剤として流動パラフィン(37.78℃における動粘度7.59×10-5m2/s)を押出機シリンダーにプランジャーポンプにより注入した。溶融混練し、押し出される全混合物中に占める流動パラフィン量比が65質量%となるように、フィーダーおよびポンプを調整した。溶融混練条件は、設定温度200℃、スクリュー回転数240rpm、吐出量12kg/hで行った。
次に同時二軸テンター延伸機へ導き、MD方向に7倍、TD方向に7倍に同時二軸延伸を行った。この時、同時二軸テンターの設定温度は125℃であった。次にメチルエチルケトン槽に導き、流動パラフィンを抽出除去した後、メチルエチルケトンを乾燥除去した。
さらにTDテンター熱固定機に導き、熱固定を行った。熱固定温度は133℃、TD緩和率0.80とした。その結果、膜厚16μm、気孔率40%、透気度160秒/100ccのポリオレフィン樹脂多孔膜を得た。
ロウ石クレイを95.0重量部とポリビニルアルコール(平均重合度1700、ケン化度99%以上)5.0重量部とを150重量部の水に均一に分散させて塗布液を調製し、ポリオレフィン樹脂多孔膜上に厚さ5μmの多孔層を形成した以外は、実施例4-5と同様にして多層多孔膜を得た。
ポリオレフィン樹脂多孔膜上に厚さ6μmの多孔層を形成した以外は、実施例4-5と同様にして多層多孔膜を得た。
ロウ石クレイを97.5重量部とポリビニルアルコール(平均重合度1700、ケン化度99%以上)2.5重量部とを150重量部の水に均一に分散させて塗布液を調製し、ポリオレフィン樹脂多孔膜上に厚さ7μmの多孔層を形成した以外は、実施例4-5と同様にして多層多孔膜を得た。
ポリオレフィン樹脂多孔膜上に厚さ8μmの多孔層を形成した以外は、実施例4-8と同様にして多層多孔膜を得た。
ロウ石クレイを94.0質量部とアクリルラテックス(固形分濃度40%、平均粒径90nm、最低成膜温度0℃以下)6.0質量部、ポリカルボン酸アンモニウム水溶液(サンノプコ製SNディスパーサント5468)1重量部、ポリオキシアルキレン系界面活性剤(サンノプコ製SNウェット980)1重量部を150質量部の水に均一に分散させて塗布液を調製し、ポリオレフィン樹脂多孔膜上に厚さ7μmの多孔層を形成した以外は、実施例4-5と同様にして多層多孔膜を得た。
ポリオレフィン樹脂多孔膜上に厚さ10μmの多孔層を形成した以外は、実施例4-7と同様にして多層多孔膜を得た。
(多孔膜の製造)
Mv70万のホモポリマーのポリエチレン47.5質量部とMv25万のホモポリマーのポリエチレン47.5質量部とMv40万のホモポリマーのポリプロピレン5質量部とを、タンブラーブレンダーを用いてドライブレンドした。得られた純ポリマー混合物99質量%に、酸化防止剤としてペンタエリスリチル-テトラキス-[3-(3,5-ジ-t-ブチル-4-ヒドロキシフェニル)プロピオネート]を1質量%添加し、再度タンブラーブレンダーを用いてドライブレンドすることにより、ポリマー等混合物を得た。得られたポリマー等混合物は窒素で置換を行った後に、二軸押出機へ窒素雰囲気下でフィーダーにより供給した。また、可塑剤として流動パラフィン(37.78℃における動粘度7.59×10-5m2/s)を押出機シリンダーにプランジャーポンプにより注入した。溶融混練し、押し出される全混合物中に占める流動パラフィン量比が65質量%となるように、フィーダーおよびポンプを調整した。溶融混練条件は、設定温度200℃、スクリュー回転数240rpm、吐出量12kg/hで行った。
次に同時二軸テンター延伸機へ導き、MD方向に7倍、TD方向に6.4倍に同時二軸延伸を行った。この時、同時二軸テンターの設定温度は118℃であった。次にメチルエチルケトン槽に導き、流動パラフィンを抽出除去した後、メチルエチルケトンを乾燥除去した。
さらにTDテンター熱固定機に導き、熱固定を行った。熱固定温度は122℃、TD緩和率0.80とした。その結果、膜厚16μm、気孔率49%、透気度155秒/100ccのポリオレフィン樹脂多孔膜を得た。
次に、ロウ石クレイを97.0質量部とポリビニルアルコール(平均重合度1700、ケン化度99%以上)3.0質量部とを150質量部の水に均一に分散させて塗布液を調製し、上記ポリオレフィン樹脂多孔膜の表面にグラビアコーターを用いて塗布した。60℃にて乾燥して水を除去し、ポリオレフィン樹脂多孔膜上に厚さ6μmの多孔層を形成した多層多孔膜を得た。
多孔膜の膜厚を12μm、気孔率を40%、透気度を120秒/100ccとしたこと以外は、実施例4-6と同様にして多層多孔膜を得た。
多孔膜の膜厚を20μm、気孔率を40%、透気度を280秒/100ccとしたことと、ポリオレフィン樹脂多孔膜上に厚さ7μmの多孔層を形成した以外は、実施例4-6と同様にして多層多孔膜を得た。
カオリン1を98.2重量部とポリビニルアルコール(平均重合度1700、ケン化度99%以上)1.8重量部とを150重量部の水に均一に分散させて塗布液を調製した以外は、実施例4-5と同様にして多層多孔膜を得た。
ポリオレフィン樹脂多孔膜上に厚さ7μmの多孔層を形成した以外は、実施例4-15と同様にして多層多孔膜を得た。
カオリン2を用いたことと、ポリオレフィン樹脂多孔膜上に厚さ6μmの多孔層を形成した以外は、実施例4-15と同様にして多層多孔膜を得た。
ポリオレフィン樹脂多孔膜上の片面に厚さ4μmの多孔層を形成してから、さらに同じポリオレフィン樹脂多孔膜上の他方の面に厚さ4μmの多孔層を形成することで、ポリオレフィン樹脂多孔膜の両面に各4μm、合計8μmの多孔層を形成した以外は、実施例4-10と同様にして多層多孔膜を得た。
多孔層を形成しなかった以外は実施例4-5と同様にして多孔膜を得た。
多孔層を形成しなかった以外は実施例4-12と同様にして多孔膜を得た。
多孔層を形成しなかった以外は実施例4-13と同様にして多孔膜を得た。
多孔層を形成しなかった以外は実施例4-14と同様にして多孔膜を得た。
多孔層を形成しなかった比較例4-3~4-6の多孔膜は、150℃での熱収縮率が50%を超える非常に大きな値を示した。
一方、カオリンを主成分とする粒子を使用した多孔層を形成した実施例4-15~4-17の多層多孔膜は、多孔層の厚さが4~7μmと薄いにもかかわらず、150℃での熱収縮率がMD方向、TD方向のいずれも5%以下と非常に小さく、良好な耐熱収縮特性を示した。しかし、多孔層の密度は、カオリンを主成分とする粒子を使用した場合、1.3~1.5g/cm3と、多孔膜の密度(0.8g/cm3)よりも非常に大きな値を示した。
実施例4-5~4-18、比較例4-3~4-6の多層多孔膜又は多孔膜のシャットダウン温度は145~148℃であり、良好なシャットダウン機能を有するものであった。多孔層を形成しなかった比較例4-3~4-6の多孔膜は、シャットダウン温度+数℃まで加熱しただけで短絡したが、ロウ石クレイを主成分とする粒子からなる多孔層を形成した実施例4-5~4-14、実施例4-18、カオリンを主成分とする粒子を使用した多孔層を形成した実施例4-15~4-17の多層多孔膜は全て200℃以上まで加熱しても短絡せず、耐熱性に非常に優れていた。
実施例4-5~4-18、比較例4-3~4-6の多層多孔膜または多孔膜をセパレータとして用いた簡易電池は、いずれも、90%以上のレート特性、サイクル特性を示した。このことから、実施例4-5~4-18、比較例4-3~4-6で製造した多層多孔膜又は多孔膜は、電池用セパレータとして使用可能なものであることが確認できた。
また、本実施の形態の多層多孔膜は、シャットダウン機能を有するので、特に、電池用セパレータに好適に用いることができる。とりわけ、リチウムイオン二次電池用の電池用セパレータに適している。
Claims (14)
- ポリオレフィン樹脂を主成分とする多孔膜の少なくとも片面に、無機粒子と樹脂性バインダとを含む多孔層を備え、前記無機粒子がケイ酸アルミニウム化合物を主成分として含む多層多孔膜。
- 前記ケイ酸アルミニウム化合物が焼成カオリンである請求項1記載の多層多孔膜。
- 前記ケイ酸アルミニウム化合物がロウ石クレイである請求項1記載の多層多孔膜。
- 前記無機粒子の平均粒径が0.1μmを超え4.0μm以下である請求項1~3のいずれか1項記載の多層多孔膜。
- 前記無機粒子において、0.2μmより大きく1.4μm以下の粒径を有する粒子が無機粒子全体に占める割合が2体積%以上である請求項1~4のいずれか1項記載の多層多孔膜。
- 前記無機粒子において、0.2μmより大きく1.0μm以下の粒径を有する粒子が無機粒子全体に占める割合が1体積%以上である請求項5記載の多層多孔膜。
- 前記無機粒子において、0.5μmより大きく2.0μm以下の粒径を有する粒子が無機粒子全体に占める割合が8体積%以上である請求項5又は6記載の多層多孔膜。
- 前記無機粒子において、0.6μmより大きく1.4μm以下の粒径を有する粒子が無機粒子全体に占める割合が1体積%以上である請求項5~7のいずれか1項記載の多層多孔膜。
- 前記無機粒子の前記多孔層中に占める割合(質量%)が、90%以上99%以下である請求項1~8のいずれか1項記載の多層多孔膜。
- 前記樹脂性バインダがポリビニルアルコールである請求項1~9のいずれか1項記載の多層多孔膜。
- 前記多孔膜が、ポリプロピレンと、ポリプロピレン以外のポリオレフィンを含む樹脂組成物からなる請求項1~10のいずれか1項記載の多層多孔膜。
- 前記樹脂組成物中の総ポリオレフィンに対するポリプロピレンの割合が、1~35質量%である請求項11記載の多層多孔膜。
- 請求項1~12のいずれか1項記載の多層多孔膜からなる非水電解液電池用セパレータ。
- 請求項13記載の非水電解液電池用セパレータと、正極と、負極と、電解液とを有する非水電解液電池。
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JP2013097912A (ja) * | 2011-10-28 | 2013-05-20 | Kyocera Corp | 二次電池 |
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JP7042338B2 (ja) * | 2018-06-08 | 2022-03-25 | 旭化成株式会社 | 多層セパレータ |
CN109411679A (zh) * | 2018-10-22 | 2019-03-01 | 乐凯胶片股份有限公司 | 陶瓷浆料、陶瓷隔膜和锂离子电池 |
EP4008837A1 (en) | 2020-12-03 | 2022-06-08 | Robert Murray-Smith | Paper based materials for the storage of electrical energy |
Citations (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP3756815B2 (ja) | 1999-06-22 | 2006-03-15 | 三菱電機株式会社 | 電池用セパレータ及び電池 |
JP2007083537A (ja) * | 2005-09-22 | 2007-04-05 | Mitsubishi Plastics Ind Ltd | 多孔積層体の製造方法および多孔積層体 |
JP2007083549A (ja) * | 2005-09-22 | 2007-04-05 | Mitsubishi Plastics Ind Ltd | 多孔積層体の製造方法および多孔積層体 |
JP2008186721A (ja) * | 2007-01-30 | 2008-08-14 | Asahi Kasei Chemicals Corp | 高耐熱性と高透過性を兼ね備えた多孔膜およびその製法 |
WO2008149986A1 (ja) * | 2007-06-06 | 2008-12-11 | Asahi Kasei E-Materials Corporation | 多層多孔膜 |
JP2009123626A (ja) | 2007-11-16 | 2009-06-04 | Japan Aviation Electronics Industry Ltd | コネクタ |
JP2009123625A (ja) | 2007-11-16 | 2009-06-04 | Towa Tsusho Kk | 面状発熱体及び該面状発熱体を用いた給湯装置 |
JP2009124117A (ja) | 2007-10-10 | 2009-06-04 | Semiconductor Energy Lab Co Ltd | 半導体基板の作製方法および半導体装置の作製方法 |
JP2009124118A (ja) | 2007-11-14 | 2009-06-04 | Nikon Corp | 露光方法及び装置、並びにデバイス製造方法 |
JP2010036355A (ja) * | 2008-07-31 | 2010-02-18 | Asahi Kasei E-Materials Corp | 多層微多孔膜の製造方法および非水電解液二次電池用セパレータ |
Family Cites Families (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5514494A (en) * | 1995-06-19 | 1996-05-07 | Corning Incorporated | Battery separator |
WO1998032184A1 (en) | 1997-01-16 | 1998-07-23 | Mitsubishi Paper Mills Limited | Separator for nonaqueous electrolyte batteries, nonaqueous electrolyte battery using it, and method for manufacturing separator for nonaqueous electrolyte batteries |
TWI315591B (en) | 2000-06-14 | 2009-10-01 | Sumitomo Chemical Co | Porous film and separator for battery using the same |
DE102005045167B4 (de) | 2005-09-21 | 2012-07-05 | Carl Freudenberg Kg | Verwendung eines vernetzten Kautschukcompounds als Material für eine Brennstoffzelle |
KR101067628B1 (ko) | 2006-08-21 | 2011-09-26 | 주식회사 엘지화학 | 점토 광물이 코팅되어 있는 시트형 분리막 및 이를 사용한전기화학 셀 |
WO2008093575A1 (ja) | 2007-01-30 | 2008-08-07 | Asahi Kasei E-Materials Corporation | 多層多孔膜及びその製造方法 |
US8304113B2 (en) * | 2007-03-05 | 2012-11-06 | Advanced Membrane Systems, Inc. | Polyolefin and ceramic battery separator for non-aqueous battery applications |
CN101276895B (zh) * | 2007-03-27 | 2013-05-29 | 比亚迪股份有限公司 | 锂离子二次电池多孔隔膜层用组合物及锂离子二次电池 |
-
2010
- 2010-05-21 EP EP20100777817 patent/EP2433795B1/en active Active
- 2010-05-21 JP JP2011514452A patent/JP4836297B2/ja active Active
- 2010-05-21 US US13/321,353 patent/US8900740B2/en active Active
- 2010-05-21 WO PCT/JP2010/058592 patent/WO2010134585A1/ja active Application Filing
- 2010-05-21 CN CN201080010198.1A patent/CN102341238B/zh active Active
- 2010-05-21 KR KR1020117020904A patent/KR101361400B1/ko active IP Right Grant
Patent Citations (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP3756815B2 (ja) | 1999-06-22 | 2006-03-15 | 三菱電機株式会社 | 電池用セパレータ及び電池 |
JP2007083537A (ja) * | 2005-09-22 | 2007-04-05 | Mitsubishi Plastics Ind Ltd | 多孔積層体の製造方法および多孔積層体 |
JP2007083549A (ja) * | 2005-09-22 | 2007-04-05 | Mitsubishi Plastics Ind Ltd | 多孔積層体の製造方法および多孔積層体 |
JP2008186721A (ja) * | 2007-01-30 | 2008-08-14 | Asahi Kasei Chemicals Corp | 高耐熱性と高透過性を兼ね備えた多孔膜およびその製法 |
WO2008149986A1 (ja) * | 2007-06-06 | 2008-12-11 | Asahi Kasei E-Materials Corporation | 多層多孔膜 |
JP2009124117A (ja) | 2007-10-10 | 2009-06-04 | Semiconductor Energy Lab Co Ltd | 半導体基板の作製方法および半導体装置の作製方法 |
JP2009124118A (ja) | 2007-11-14 | 2009-06-04 | Nikon Corp | 露光方法及び装置、並びにデバイス製造方法 |
JP2009123626A (ja) | 2007-11-16 | 2009-06-04 | Japan Aviation Electronics Industry Ltd | コネクタ |
JP2009123625A (ja) | 2007-11-16 | 2009-06-04 | Towa Tsusho Kk | 面状発熱体及び該面状発熱体を用いた給湯装置 |
JP2010036355A (ja) * | 2008-07-31 | 2010-02-18 | Asahi Kasei E-Materials Corp | 多層微多孔膜の製造方法および非水電解液二次電池用セパレータ |
Non-Patent Citations (1)
Title |
---|
See also references of EP2433795A4 |
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Also Published As
Publication number | Publication date |
---|---|
EP2433795A1 (en) | 2012-03-28 |
CN102341238B (zh) | 2015-09-16 |
CN102341238A (zh) | 2012-02-01 |
EP2433795A4 (en) | 2013-04-24 |
KR20110114713A (ko) | 2011-10-19 |
US8900740B2 (en) | 2014-12-02 |
KR101361400B1 (ko) | 2014-02-10 |
US20120141859A1 (en) | 2012-06-07 |
JPWO2010134585A1 (ja) | 2012-11-12 |
JP4836297B2 (ja) | 2011-12-14 |
EP2433795B1 (en) | 2014-02-26 |
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