Classifications

• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01G—CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES, LIGHT-SENSITIVE OR TEMPERATURE-SENSITIVE DEVICES OF THE ELECTROLYTIC TYPE
  • H01G11/00—Hybrid capacitors, i.e. capacitors having different positive and negative electrodes; Electric double-layer [EDL] capacitors; Processes for the manufacture thereof or of parts thereof
  • H01G11/78—Cases; Housings; Encapsulations; Mountings
  • H01G11/80—Gaskets; Sealings
• • 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
  • H01M50/10—Primary casings; Jackets or wrappings
  • H01M50/102—Primary casings; Jackets or wrappings characterised by their shape or physical structure
  • H01M50/105—Pouches or flexible bags
• • 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
  • H01M50/10—Primary casings; Jackets or wrappings
  • H01M50/116—Primary casings; Jackets or wrappings characterised by the material
  • H01M50/117—Inorganic material
  • H01M50/119—Metals
• • 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
  • H01M50/10—Primary casings; Jackets or wrappings
  • H01M50/116—Primary casings; Jackets or wrappings characterised by the material
  • H01M50/121—Organic material
• • 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
  • H01M50/10—Primary casings; Jackets or wrappings
  • H01M50/116—Primary casings; Jackets or wrappings characterised by the material
  • H01M50/124—Primary casings; Jackets or wrappings characterised by the material having a layered structure
  • H01M50/126—Primary casings; Jackets or wrappings characterised by the material having a layered structure comprising three or more layers
  • H01M50/129—Primary casings; Jackets or wrappings characterised by the material having a layered structure comprising three or more layers with two or more layers of only organic material
• • 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
  • H01M50/10—Primary casings; Jackets or wrappings
  • H01M50/172—Arrangements of electric connectors penetrating the casing
  • H01M50/174—Arrangements of electric connectors penetrating the casing adapted for the shape of the cells
  • H01M50/178—Arrangements of electric connectors penetrating the casing adapted for the shape of the cells for pouch or flexible bag cells
• • 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
  • H01M50/10—Primary casings; Jackets or wrappings
  • H01M50/183—Sealing members
  • H01M50/184—Sealing members characterised by their shape or structure
• • 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
  • H01M50/10—Primary casings; Jackets or wrappings
  • H01M50/183—Sealing members
  • H01M50/186—Sealing members characterised by the disposition of the sealing members
• • 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
  • H01M50/10—Primary casings; Jackets or wrappings
  • H01M50/183—Sealing members
  • H01M50/19—Sealing members characterised by the material
  • H01M50/193—Organic material
• • 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
  • H01M50/10—Primary casings; Jackets or wrappings
  • H01M50/183—Sealing members
  • H01M50/19—Sealing members characterised by the material
  • H01M50/197—Sealing members characterised by the material having a layered structure
• • 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
  • H01M50/10—Primary casings; Jackets or wrappings
  • H01M50/183—Sealing members
  • H01M50/19—Sealing members characterised by the material
  • H01M50/198—Sealing members characterised by the material characterised by physical properties, e.g. adhesiveness or hardness
• • 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

Definitions

• the present disclosure relates to an adhesive film for metal terminals and a manufacturing method thereof, a metal terminal with an adhesive film for metal terminals, an exterior material for an electricity storage device, a kit including an exterior material for an electricity storage device and an adhesive film for metal terminals, and an electricity storage device and a manufacturing method thereof.
• a laminate sheet in which a base layer, an adhesive layer, a barrier layer, and a heat-sealable resin layer are laminated in that order has been proposed as an exterior material for an electricity storage device that can be easily processed into a variety of shapes and can be made thinner and lighter.
• the heat-sealable resin layers located in the innermost layers of the exterior material for an electricity storage device are placed opposite each other, and the peripheral portion of the exterior material for an electricity storage device is heat-sealed to seal the electricity storage device element with the exterior material for an electricity storage device.
• Metal terminals protrude from the heat-sealed portion of the exterior material for electricity storage devices, and the electricity storage device element sealed with the exterior material for electricity storage devices is electrically connected to the outside via the metal terminals that are electrically connected to the electrodes of the electricity storage device element.
• the portion of the heat-sealed portion of the exterior material for electricity storage devices where the metal terminals are present is heat-sealed in a state where the metal terminals are sandwiched between the heat-sealable resin layer. Because the metal terminals and the heat-sealable resin layer are made of different materials, adhesion is likely to decrease at the interface between the metal terminals and the heat-sealable resin layer.
• an adhesive film may be placed between the metal terminal and the heat-sealable resin layer in order to improve adhesion between them.
• An example of such an adhesive film is that described in Patent Document 1.
• the heat-sealable resin layer and the metal terminal of the exterior material for an electricity storage device are made of different materials, so adhesion is likely to decrease at the interface between the metal terminal and the heat-sealable resin layer. For this reason, an adhesive film is sometimes placed between the metal terminal and the heat-sealable resin layer for the purpose of improving adhesion between them.
• the main object of the present disclosure is to provide an adhesive film for metal terminals that is interposed between a metal terminal electrically connected to an electrode of an electricity storage device element and an exterior material for an electricity storage device that seals the electricity storage device element, and that can exhibit high adhesive strength when the adhesive film is heat-sealed to the heat-sealable resin layer of the exterior material for an electricity storage device. Furthermore, the present disclosure also aims to provide a method for manufacturing the adhesive film for metal terminals, a metal terminal with an adhesive film for metal terminals, an exterior material for an electricity storage device, a kit including an exterior material for an electricity storage device and the adhesive film for metal terminals, an electricity storage device, and a method for manufacturing the electricity storage device.
• the inventors of the present disclosure have conducted intensive research to solve the above problems.
• the exterior material for an electricity storage device has a heat-sealable resin layer arranged on the outermost surface on the electricity storage device element side, one surface of the adhesive film for metal terminal is composed of resin layer A, and the adhesive film for metal terminal and the metal terminal are heat-sealed under conditions of a temperature of 200°C, a pressure of 0.25 MPa, and a time of 16 seconds to form a metal terminal arranged so that the resin layer A is located on the surface.
• An adhesive film for a metal terminal which is interposed between a metal terminal electrically connected to an electrode of an electricity storage device element and an exterior material for an electricity storage device that encapsulates the electricity storage device element, the electrical storage device exterior material includes a thermally adhesive resin layer disposed on an outermost surface on the electrical storage device element side,
• the adhesive film for metal terminal has one surface composed of a resin layer A,
• the adhesive film for metal terminal and the metal terminal are heat-sealed under conditions of a temperature of 200°C, a pressure of 0.25 MPa, and a time of 16 seconds to obtain a metal terminal with an adhesive film for metal terminal, in which the resin layer A is positioned on the surface; and when the adhesive film for metal terminal of the metal terminal with the adhesive film for metal terminal and the heat-sealable resin layer having a crystalline lamellar thickness of 5.0 to 9.0 nm are heat-sealed under conditions of a temperature of 200°C, a pressure of 1.0 MP
• an adhesive film for metal terminals that is interposed between a metal terminal electrically connected to an electrode of an electricity storage device element and an exterior material for an electricity storage device that seals the electricity storage device element, and that can exhibit high adhesive strength when the adhesive film and the heat-sealable resin layer of the exterior material for an electricity storage device are heat-sealed. Furthermore, it is an object of the present disclosure to provide a method for manufacturing the adhesive film for metal terminals, a metal terminal with an adhesive film for metal terminals, an exterior material for an electricity storage device, a kit including an exterior material for an electricity storage device and an adhesive film for metal terminals, and an electricity storage device and a method for manufacturing the same.
• FIG. 2 is a schematic plan view of the electricity storage device of the present disclosure.
• 2 is a schematic cross-sectional view taken along line A-A' in FIG. 1.
• 2 is a schematic cross-sectional view taken along line B-B' in FIG. 1.
• 1 is a schematic cross-sectional view of an adhesive film for metal terminals according to the present disclosure.
• 1 is a schematic cross-sectional view of an adhesive film for metal terminals according to the present disclosure.
• 1 is a schematic cross-sectional view of an adhesive film for metal terminals according to the present disclosure.
• 1 is a schematic cross-sectional view of an adhesive film for metal terminals according to the present disclosure.
• 1 is a schematic cross-sectional view of an exterior material for an electricity storage device according to the present disclosure.
• FIG. 2 is a schematic diagram for explaining a method for measuring the adhesive strength between an adhesive film and an exterior material.
• FIG. 2 is a schematic diagram for explaining a method for measuring the adhesive strength between an adhesive film and an exterior material.
• the adhesive film for metal terminals disclosed herein is an adhesive film for metal terminals that is interposed between a metal terminal electrically connected to an electrode of an electricity storage device element and an exterior material for an electricity storage device that encapsulates the electricity storage device element.
• the exterior material for an electricity storage device has a heat-sealable resin layer that is disposed on the outermost surface on the electricity storage device element side.
• the adhesive film for metal terminals has one surface made of resin layer A, and the adhesive film for metal terminals and the metal terminal are heat-sealed under conditions of a temperature of 200°C, a pressure of 0.25 MPa, and a time of 16 seconds to obtain a metal terminal with an adhesive film for metal terminals arranged so that the resin layer A is located on the surface, and when the adhesive film for metal terminals of the metal terminal with adhesive film for metal terminals and the heat-sealable resin layer having a crystalline lamellar thickness of 5.0 to 9.0 nm are heat-sealed under conditions of a temperature of 200°C, a pressure of 1.0 MPa, and a time of 3 seconds, the difference between the crystalline lamellar thickness A of the resin layer A of the adhesive film for metal terminals and the crystalline lamellar thickness B of the heat-sealable resin layer is 0.3 nm or less at the heat-sealed portion between the adhesive film for metal terminals and the heat-sealable resin layer
• the adhesive film for metal terminals disclosed herein has these characteristics, and therefore can exhibit high adhesive strength when the adhesive film is heat-sealed to the heat-sealable resin layer of the exterior material for the electricity storage device.
• the electricity storage device of the present disclosure is an electricity storage device that includes at least an electricity storage device element having a positive electrode, a negative electrode, and an electrolyte, an exterior material for an electricity storage device that seals the electricity storage device element, and metal terminals that are electrically connected to the positive electrode and the negative electrode, respectively, and protrude to the outside of the exterior material for an electricity storage device, and is characterized in that the adhesive film for metal terminals of the present disclosure is interposed between the metal terminals and the exterior material for an electricity storage device.
• the numerical ranges indicated with “ ⁇ ” mean “greater than or equal to” or “less than or equal to.”
• the expression 2 to 15 mm means 2 mm or greater and 15 mm or less.
• the upper or lower limit value described in a certain numerical range may be replaced with the upper or lower limit value of another numerical range described in stages.
• a numerical range may be formed by combining an upper limit value and an upper limit value, an upper limit value and a lower limit value, or a lower limit value and a lower limit value, each of which is described separately.
• the upper or lower limit value described in a certain numerical range may be replaced with a value shown in the examples.
• a method for confirming the MD of an adhesive film for metal terminals there is a method of observing a cross section of the adhesive film for metal terminals (e.g., a cross section of an acid-modified polyolefin layer or a polyolefin layer) with an electron microscope to confirm the sea-island structure.
• a cross section of the adhesive film for metal terminals e.g., a cross section of an acid-modified polyolefin layer or a polyolefin layer
• an electron microscope to confirm the sea-island structure.
• the cross section in the length direction of the adhesive film for metal terminals and each cross section (10 cross sections in total) at an angle of 10 degrees from the direction parallel to the cross section in the length direction to the direction perpendicular to the cross section in the length direction are observed with an electron microscope to confirm the sea-island structure.
• the shape of each individual island is observed in each cross section.
• the straight line distance connecting the leftmost end in the direction perpendicular to the thickness direction of the adhesive film for metal terminals and the rightmost end in the perpendicular direction is taken as the diameter y.
• the average of the diameters y of the top 20 island shapes in descending order of diameter y is calculated.
• the direction parallel to the cross section in which the average diameter y of the island shape is the largest is determined to be the MD.
• the adhesive film for metal terminals can be left in a 150°C environment for 2 minutes, and the thermal shrinkage rate measured, and the direction with the larger shrinkage rate can be determined to be the MD.
• Adhesive film for metal terminal The adhesive film for metal terminal of the present disclosure is interposed between a metal terminal electrically connected to an electrode of an electricity storage device element and an exterior material for an electricity storage device that seals the electricity storage device element.
• the adhesive film for metal terminal 1 of the present disclosure is interposed between a metal terminal 2 electrically connected to an electrode of an electricity storage device element 4 and an exterior material for an electricity storage device 3 that seals the electricity storage device element 4.
• the metal terminal 2 protrudes outside the exterior material for an electricity storage device 3, and is sandwiched by the exterior material for an electricity storage device 3 via the adhesive film for metal terminal 1 at the peripheral portion 3a of the heat-sealed exterior material for an electricity storage device 3.
• the temporary adhesion process of the adhesive film for metal terminals to the metal terminals is carried out, for example, under conditions of a temperature of about 140-160°C, a pressure of about 0.01-1.0 MPa, a time of about 3-15 seconds, and a number of times of about 3-6, while the main adhesion process is carried out, for example, under conditions of a temperature of about 160-240°C, a pressure of about 0.01-1.0 MPa, a time of about 3-15 seconds, and a number of times of about 1-3.
• the heating temperature when the metal terminal with the adhesive film for metal terminal is interposed between the exterior material for the electricity storage device and heat sealed is usually in the range of about 180-210°C, and the pressure is usually about 1.0-5.0 MPa, a time of about 1-5 seconds, and a number of times of about 1.
• the adhesive film 1 for metal terminals of the present disclosure is provided to improve the adhesion between the metal terminal 2 and the exterior material 3 for the electric storage device.
• the sealing property of the electric storage device element 4 is improved. As described above, when the electric storage device element 4 is heat-sealed, the electric storage device element is sealed so that the metal terminal 2 electrically connected to the electrode of the electric storage device element 4 protrudes outside the exterior material 3 for the electric storage device.
• the metal terminal 2 made of metal and the heat-sealable resin layer 35 (a layer made of a heat-sealable resin such as polyolefin) located in the innermost layer of the exterior material 3 for the electric storage device are made of different materials, if such an adhesive film is not used, the sealing property of the electric storage device element is likely to be reduced at the interface between the metal terminal 2 and the heat-sealable resin layer 35.
• the adhesive film 1 for metal terminal of the present disclosure includes at least a resin layer A.
• the resin layer A forms at least one surface of the adhesive film 1 for metal terminal and is the outermost layer. That is, the adhesive film 1 for metal terminal of the present disclosure includes at least one resin layer A, and at least one surface of the adhesive film 1 for metal terminal is formed by the resin layer A.
• the adhesive film 1 for metal terminal of the present disclosure may be a single layer as shown in FIG. 4, or may have a multilayer structure (multiple layers) as shown in FIGS. 5 to 7.
• the adhesive film 1 for metal terminals of the present disclosure is a single layer
• the adhesive film 1 for metal terminals is composed of a resin layer A
• the surface on the metal terminal side and the surface of the exterior material for a storage battery device are formed by the resin layer A.
• the resin forming the surface on the exterior material for a storage battery device side of the adhesive film 1 for metal terminals and the resin forming the surface on the metal terminal side are a common resin (i.e., the resin constituting the resin layer A).
• the resin forming the surface on the exterior material for a storage battery device side of the adhesive film 1 for metal terminals and the resin forming the surface on the metal terminal side being common means that, for example, 80% by mass or more of the components in these resins are preferably the same, more preferably 90% by mass or more are the same, even more preferably 95% by mass or more are the same, and even more preferably 100% by mass are the same.
• the adhesive film 1 for metal terminals of the present disclosure has a multi-layer structure (multi-layer)
• at least one layer may be composed of the resin layer A.
• the adhesive film 1 for metal terminals of the present disclosure has a two-layer structure
• the adhesive film 1 for metal terminals is a laminate of a first resin layer 12a and a second resin layer 12b.
• the second resin layer 12b is composed of the resin layer A.
• the second resin layer 12b (resin layer A) faces the heat-sealable resin layer of the outer layer material for the electric storage device and can be heat-sealed.
• the adhesive film 1 for metal terminals of the present disclosure has a multi-layer structure (multi-layer)
• the resin forming the surface of the outer layer material for the electric storage device and the resin forming the surface of the metal terminal may be the same resin.
• the adhesive film 1 for metal terminals of the present disclosure when the adhesive film 1 for metal terminals of the present disclosure has a three-layer structure, the adhesive film 1 for metal terminals is a laminate in which a first resin layer 12a, an intermediate layer 11, and a second resin layer 12b are laminated in this order.
• the first resin layer 12a forms the surface on the metal terminal side
• the second resin layer 12b forms the surface on the exterior material side for the electricity storage device.
• the surface of the adhesive film 1 for metal terminals of the present disclosure that faces the exterior material for an electrical storage device i.e., the surface of the second resin layer 12b (resin layer A)
• the first resin layer 12a and the second resin layer 12b at least the second resin layer 12b is formed by the resin layer A.
• the first resin layer 12a constituting the surface on the metal terminal side of the adhesive film 1 for metal terminals of the present disclosure has thermal adhesion to metal (the metal constituting the metal terminal). Therefore, when using the adhesive film 1 for metal terminals of the present disclosure, it is preferable to use the first resin layer 12a by placing it on the metal terminal side.
• the resin layer A is preferably a layer containing a polyolefin skeleton such as polyolefin, and more preferably a layer containing polyolefin. From the viewpoint of more suitably exerting the effects of the present disclosure, the resin layer A is preferably formed from polyolefin. In other words, the resin layer A can be suitably constituted from a polyolefin film.
• polyolefins include polyethylenes such as low-density polyethylene, medium-density polyethylene, high-density polyethylene, and linear low-density polyethylene; crystalline or amorphous polypropylenes such as homopolypropylene, block copolymers of polypropylene (e.g., block copolymers of propylene and ethylene), and random copolymers of polypropylene (e.g., random copolymers of propylene and ethylene); and ethylene-butene-propylene terpolymers.
• polyethylene and polypropylene are preferred, and polypropylene is particularly preferred.
• the polyolefin may be a cyclic polyolefin.
• Cyclic polyolefins are copolymers of olefins and cyclic monomers.
• olefins that are constituent monomers of the cyclic polyolefin include ethylene, propylene, 4-methyl-1-pentene, butadiene, and isoprene.
• cyclic monomers that are constituent monomers of the cyclic polyolefin include cyclic alkenes such as norbornene; specifically, cyclic dienes such as cyclopentadiene, dicyclopentadiene, cyclohexadiene, and norbornadiene.
• cyclic alkenes are preferred, and norbornene is more preferred.
• Styrene is also an example of a constituent monomer.
• the polyolefin may be an acid-modified polyolefin (i.e., an acid-modified polyolefin).
• an acid-modified polyolefin there are no particular limitations on the acid-modified polyolefin, so long as it is an acid-modified polyolefin, but preferred examples include polyolefins graft-modified with an unsaturated carboxylic acid or anhydride thereof.
• polyolefins to be acid-modified include polyethylenes such as low-density polyethylene, medium-density polyethylene, high-density polyethylene, and linear low-density polyethylene; crystalline or amorphous polypropylenes such as homopolypropylene, block copolymers of polypropylene (e.g., block copolymers of propylene and ethylene), and random copolymers of polypropylene (e.g., random copolymers of propylene and ethylene); and ethylene-butene-propylene terpolymers.
• polyethylene and polypropylene are preferred, and polypropylene is particularly preferred.
• the polyolefin to be acid-modified may also be a cyclic polyolefin.
• a carboxylic acid-modified cyclic polyolefin is a polymer obtained by copolymerizing a portion of the monomers constituting the cyclic polyolefin with an ⁇ , ⁇ -unsaturated carboxylic acid or its anhydride, or by block polymerizing or graft polymerizing an ⁇ , ⁇ -unsaturated carboxylic acid or its anhydride onto a cyclic polyolefin.
• the acid-modified cyclic polyolefin is a copolymer of an olefin and a cyclic monomer
• examples of the olefins that are constituent monomers of the cyclic polyolefin include ethylene, propylene, 4-methyl-1-pentene, butadiene, and isoprene.
• examples of the cyclic monomers that are constituent monomers of the cyclic polyolefin include cyclic alkenes such as norbornene; specifically, cyclic dienes such as cyclopentadiene, dicyclopentadiene, cyclohexadiene, and norbornadiene.
• cyclic alkenes are preferred, and norbornene is more preferred.
• Styrene is also an example of a constituent monomer.
• Examples of the carboxylic acid or its anhydride used for the acid modification include maleic acid, acrylic acid, itaconic acid, crotonic acid, maleic anhydride, and itaconic anhydride.
• the resin layer A is analyzed by infrared spectroscopy, it is preferable that a peak derived from maleic anhydride is detected.
• peaks derived from maleic anhydride are detected at wave numbers of about 1760 cm -1 and about 1780 cm -1 .
• the resin layer A is a layer composed of maleic anhydride-modified polyolefin
• a peak derived from maleic anhydride is detected by infrared spectroscopy.
• the peak may be small and not detected. In that case, it can be analyzed by nuclear magnetic resonance spectroscopy.
• the adhesive film 1 for metal terminals has a multilayer structure (multiple layers) as shown in Figures 5 to 7, it is sufficient that the surface on the metal terminal side is provided with a resin layer that has thermal adhesion to the metal, while the surface of the exterior material for an electricity storage device is provided with a resin layer A that has thermal adhesion only to the thermally adhesive resin layer of the exterior material for an electricity storage device.
• the resin used in the thermally adhesive resin layer of the exterior material for an electricity storage device is an acid-unmodified polyolefin, particularly an acid-unmodified polypropylene, and that resins of the same type have excellent thermal adhesion
• the resin layer A can be suitably constituted by an acid-unmodified polyolefin film, particularly an acid-unmodified polypropylene film.
• the adhesive film for metal terminals has one surface composed of resin layer A, and the adhesive film for metal terminals and the metal terminal are heat-sealed under conditions of a temperature of 200°C, a pressure of 0.25 MPa, and a time of 16 seconds (one time) to obtain a metal terminal with an adhesive film arranged so that resin layer A is located on the surface, and when the adhesive film of the metal terminal with adhesive film is heat-sealed to a heat-sealable resin layer having a crystalline lamellar thickness of 5.0 to 9.0 nm under conditions of a temperature of 200°C, a pressure of 1.0 MPa, and a time of 3 seconds, the difference between the crystalline lamellar thickness A of the resin layer A of the adhesive film and the crystalline lamellar thickness B of the heat-sealable resin layer is 0.3 nm or less at the heat-sealed portion between the adhesive film and the heat-sealable resin layer.
• the difference is preferably 0.29 nm or less, more preferably 0.25 nm or less, and even more preferably 0.20 nm or less.
• the lower limit of the difference can be, for example, 0.00 nm or 0.01 nm, and preferred ranges include about 0.00 to 0.30 nm, about 0.00 to 0.29 nm, about 0.00 to 0.25 nm, about 0.00 to 0.20 nm, about 0.1 to 0.30 nm, about 0.10 to 0.29 nm, about 0.10 to 0.25 nm, and about 0.10 to 0.20 nm.
• the crystalline lamellar thickness A of the resin layer A of the adhesive film is preferably 4.0 nm or more, more preferably 4.5 nm or more, and even more preferably 5.0 nm or more, and is preferably 10.0 nm or less, more preferably 9.5 nm or less, and even more preferably 9.0 nm or less.
• Preferred ranges include about 4.0 to 10.0 nm, about 4.0 to 9.5 nm, about 4.0 to 9.0 nm, about 4.5 to 10.0 nm, about 4.5 to 9.5 nm, about 4.5 to 9.0 nm, about 5.0 to 10.0 nm, about 5.0 to 9.5 nm, and about 5.0 to 9.0 nm.
• the crystal lamella thickness B of the heat-sealable resin layer of the exterior material for an electrical storage device is preferably 5.1 nm or more, more preferably 5.5 nm or more, and even more preferably 6.0 nm or more, and is preferably 9.0 nm or less, more preferably 8.5 nm or less, and even more preferably 8.0 nm or less.
• Preferred ranges include about 5.0 to 9.0 nm, about 5.0 to 8.5 nm, about 5.0 to 8.0 nm, about 5.1 to 9.0 nm, about 5.1 to 8.5 nm, about 5.1 to 8.0 nm, about 5.5 to 9.0 nm, about 5.5 to 8.5 nm, about 5.5 to 8.0 nm, about 6.0 to 9.0 nm, about 6.0 to 8.5 nm, and about 6.0 to 8.0 nm.
• the resin layer A is arranged on the outermost surface.
• the adhesive film of the metal terminal with the adhesive film and a heat-sealable resin layer (heat-sealable resin layer made of random polypropylene resin (MD 120 mm, TD 30 mm, thickness 80 ⁇ m)) having a crystal lamellar thickness of 5.0 to 9.0 nm of the exterior material for a storage battery device are heat-sealed under the conditions of a temperature of 200° C., a pressure of 1.0 MPa, and a time of 3 seconds to obtain a sample for measurement.
• the MD of the adhesive film and the TD of the heat-sealable resin layer of the electrical storage device packaging material are made to coincide with each other.
• STEM observation is performed from the cross-sectional direction of the heat-sealed portion between the adhesive film and the heat-sealable resin layer under the following measurement conditions, and the crystalline lamellar thickness A of the resin layer A of the adhesive film and the crystalline lamellar thickness B of the heat-sealable resin layer of the electrical storage device packaging material are measured under the following measurement conditions using the following image processing conditions for the obtained image data.
• Methods for adjusting the crystalline lamellar thickness A of the resin layer A of the adhesive film include, for example, the molding method when forming the resin layer A (for example, the type of molding method such as extrusion method or inflation method, cooling temperature, cooling time, line speed, clearance), resin blend, and selection of resin type.
• the molding method when forming the resin layer A for example, the type of molding method such as extrusion method or inflation method, cooling temperature, cooling time, line speed, clearance
• resin blend for example, if the cooling rate after film formation is slowed, the crystalline lamellar thickness A tends to increase, and, for example, if the cooling rate after film formation is fast, the crystalline lamellar thickness A tends to decrease.
• the film formation temperature, film formation speed, and cooling conditions are conditions that have a large effect on the cooling rate of the resin layer A.
• the extruded resin will be rapidly cooled. This will result in a small crystalline lamellar thickness.
• the film formation temperature and film formation speed are low and the chill roll temperature is high, the extruded resin will be slowly cooled, and the crystalline lamellar thickness will increase.
• the thickness of the resin layer A also affects the crystalline lamellar thickness.
• a heat-sealable resin layer with a crystalline lamellar thickness of 5.0 to 9.0 nm is prepared, and a measurement sample is prepared as described above to measure the crystalline lamellar thicknesses A and B.
• a resin film for forming the resin layer A is selected (for example, it may be selected from commercially available products, etc.), and the resin film with a difference between the crystalline lamellar thicknesses A and B of 0.3 nm or less is used as the resin layer A of the present disclosure.
• the difference between the crystalline lamellar thicknesses A and B is 0.3 nm or less, so that high adhesive strength can be exhibited when the adhesive film and the heat-sealable resin layer of the exterior material for the electric storage device are heat-sealed.
• the reason for this can be considered as follows.
• the difference between the crystalline lamellar thickness A of the resin layer A of the adhesive film and the crystalline lamellar thickness B of the heat-sealable resin layer of the exterior material for the electric storage device is a very small value of 0.3 nm or less, so that it can be evaluated that these layers are easily mixed at the interface between the resin layer A and the heat-sealable resin layer, and integration is promoted, and as a result, it can be considered that these layers are firmly bonded to each other, and high adhesive strength is exhibited.
• the adhesive film of the present disclosure has a temperature at 90% volume melting (the melting temperature (°C) when the adhesive film of the present disclosure is heated by the method described below and the melting ratio is 90% by volume) of preferably 100°C or higher, more preferably 105°C or higher, even more preferably 107°C or higher, and preferably 120°C or lower, more preferably 117°C or lower, even more preferably 115°C or lower, with preferred ranges being approximately 100-120°C, approximately 100-117°C, approximately 100-115°C, approximately 105-120°C, approximately 105-117°C, approximately 105-115°C, approximately 107-120°C, approximately 107-117°C, and approximately 107-115°C.
• the temperature of resin layer A at 75% by volume melting is preferably 100°C or higher, more preferably 103°C or higher, and even more preferably 105°C or higher, and is preferably 120°C or lower, more preferably 118°C or lower, and even more preferably 116°C or lower, with preferred ranges being about 100 to 120°C, about 100 to 118°C, about 100 to 116°C, about 103 to 120°C, about 103 to 118°C, about 103 to 116°C, about 105 to 120°C, about 105 to 118°C, and about 105 to 116°C.
• the temperature of resin layer A at 50% by volume melting is preferably 95°C or higher, more preferably 98°C or higher, and even more preferably 100°C or higher, and is preferably 115°C or lower, more preferably 112°C or lower, and even more preferably 110°C or lower, with preferred ranges being about 95 to 115°C, about 95 to 112°C, about 95 to 110°C, about 98 to 115°C, about 98 to 112°C, about 98 to 110°C, about 100 to 115°C, about 100 to 112°C, and about 100 to 110°C.
• the temperature of resin layer A at 25% by volume melting is preferably 90°C or higher, more preferably 92°C or higher, and even more preferably 94°C or higher, and is preferably 108°C or lower, more preferably 106°C or lower, and even more preferably 104°C or lower, with preferred ranges being about 90 to 108°C, about 90 to 106°C, about 90 to 104°C, about 92 to 108°C, about 92 to 106°C, about 92 to 104°C, about 94 to 108°C, about 94 to 106°C, and about 94 to 104°C.
• the temperature of the resin layer A at 10% volume melting is preferably 84°C or higher, more preferably 86°C or higher, and even more preferably 88°C or higher, and is preferably 102°C or lower, more preferably 100°C or lower, and even more preferably 98°C or lower, with preferred ranges being about 84-102°C, about 84-100°C, about 84-98°C, about 86-102°C, about 86-100°C, about 86-98°C, about 88-102°C, about 88-100°C, and about 88-98°C.
• the temperature at 25% volume melting is low, it is advantageous when the heat-sealable resin layer of the exterior material and the adhesive film are heat-sealed in a low-temperature environment.
• ⁇ Melting ratio (volume %) and melting temperature (°C) of adhesive film> According to the following procedure, an adhesive film is heated to 210°C to melt it, and then cooled from 210°C at a temperature drop rate of 10°C/min, and the temperatures when the adhesive film is 90% melted by volume, 75% melted by volume, 50% melted by volume, 25% melted by volume, and 10% melted by volume are measured.
• the heat of fusion of each measurement sample is measured in accordance with the provisions of JIS K 7122:2012.
• the measurement is performed using a differential scanning calorimeter.
• the measurement sample is held at -50°C for 15 minutes, then heated from -50°C to 210°C at a heating rate of 10°C/min, the first heat of fusion ⁇ H (J/g) is measured, and then held at 210°C for 10 minutes.
• the temperature is lowered from 210°C to -50°C at a heating rate of 10°C/min and held for 15 minutes.
• the temperature is raised from -50°C to 210°C at a heating rate of 10°C/min to measure the second heat of fusion ⁇ H (J/g).
• the flow rate of nitrogen gas is 50 ml/min.
• the value of the heat of fusion ⁇ H (J/g) measured in the first time by the above procedure is adopted.
• the heat of fusion is defined as the melting peak area surrounded by the baseline (a straight line connecting 80°C to 170°C on the DSC curve) and the peak in the DSC curve.
• the heat of fusion of crystals in a temperature range below X°C is calculated from the area of the melting peak area in the temperature range below X°C when calculating the total heat of fusion of crystals.
• the "melting rate at temperature X°C" is a value calculated from the following formula.
• the resin layer A may be formed from one type of resin component alone, or from a blended polymer combining two or more types of resin components. From the viewpoint of film formability, it is preferable that the resin layer A is formed from a blended polymer combining two or more types of resin components. When using a blended polymer, it is preferable that the resin layer A contains, for example, polypropylene as the main component (a component of 50% by mass or more) and 50% by mass or less of another resin (preferably polyethylene from the viewpoint of improving flexibility). On the other hand, from the viewpoint of the electrolyte resistance of the resin layer A, it is preferable that the resin layer A contains polypropylene alone as the resin.
• Resin layer A may contain known additives as necessary, to the extent that they do not impair the effects of the present disclosure.
• the resin layer A may contain a filler as necessary.
• the filler functions as a spacer, making it possible to effectively suppress short circuits between the metal terminal 2 and the barrier layer 33 of the exterior material 3 for an electrical storage device.
• the particle size of the filler is about 0.1 to 35 ⁇ m, preferably about 5.0 to 30 ⁇ m, and more preferably about 10 to 25 ⁇ m.
• the content of the filler is about 5 to 30 parts by mass, and more preferably about 10 to 20 parts by mass, relative to 100 parts by mass of the resin component that forms the resin layer A.
• inorganic fillers include carbon (carbon, graphite), silica, aluminum oxide, barium titanate, iron oxide, silicon carbide, zirconium oxide, zirconium silicate, magnesium oxide, titanium oxide, calcium aluminate, calcium hydroxide, aluminum hydroxide, magnesium hydroxide, calcium carbonate, etc.
• organic fillers include fluororesin, phenolic resin, urea resin, epoxy resin, acrylic resin, benzoguanamine-formaldehyde condensate, melamine-formaldehyde condensate, polymethyl methacrylate crosslinked product, polyethylene crosslinked product, etc.
• the filler can be mixed into the resin component that forms the resin layer A by melt-blending the two in advance using a Banbury mixer or the like to create a master batch and mixing it in a specified ratio, or by directly mixing it with the resin component.
• the resin layer A may also contain a pigment if necessary.
• a pigment various inorganic pigments can be used.
• a specific example of the pigment is preferably carbon (carbon, graphite) as exemplified in the filler above.
• Carbon (carbon, graphite) is a material that is generally used inside an electricity storage device and is not likely to dissolve in the electrolyte.
• it has a large coloring effect and can obtain a sufficient coloring effect with an amount added that does not inhibit adhesion, and it does not melt due to heat, and can increase the apparent melt viscosity of the added resin.
• it can prevent the pressurized part from becoming thin during heat adhesion (heat sealing), and can provide excellent sealing between the exterior material for electricity storage devices and the metal terminal.
• the amount of the pigment added is, for example, about 0.05 to 0.3 parts by mass, preferably about 0.1 to 0.2 parts by mass, per 100 parts by mass of the resin components forming the resin layer A when carbon black with a particle size of about 0.03 ⁇ m is used.
• the presence or absence of the adhesive film 1 for metal terminals can be detected by a sensor or visually inspected.
• the filler and the pigment may be added to the same resin layer A, but from the viewpoint of not impairing the thermal fusion properties of the adhesive film 1 for metal terminals, it is preferable to add the filler and the pigment separately to different layers (for example, the first resin layer 12a, the second resin layer 12b, the intermediate layer 11, etc. described below).
• the melting peak temperature of resin layer A is preferably 125°C or higher, more preferably about 130°C or higher, and even more preferably about 135°C or higher. From the same viewpoint, the melting peak temperature is, for example, 180°C or lower, preferably 175°C or lower, more preferably 170°C or lower, even more preferably about 165°C or lower, and even more preferably about 160°C or lower.
• Preferred ranges of the melting peak temperature include about 125 to 180°C, about 125 to 175°C, about 125 to 170°C, about 125 to 165°C, about 125 to 160°C, about 130 to 180°C, about 130 to 175°C, about 130 to 170°C, about 130 to 165°C, about 130 to 160°C, about 135 to 180°C, about 135 to 175°C, about 135 to 170°C, about 135 to 165°C, and about 135 to 160°C.
• the method for measuring the melting peak temperature is as follows.
• the melting peak temperature of each measurement sample is measured in accordance with the provisions of JIS K7121:2012 (Method of measuring transition temperature of plastics (JIS K7121:1987 Supplement 1)). The measurement is performed using a differential scanning calorimeter (DSC). The measurement sample is held at -50°C for 15 minutes, then heated from -50°C to 210°C at a heating rate of 10°C/min, the first melting peak temperature P (°C) is measured, and then held at 210°C for 10 minutes. Next, the temperature is lowered from 210°C to -50°C at a heating rate of 10°C/min and held for 15 minutes.
• DSC differential scanning calorimeter
• the temperature is raised from -50°C to 210°C at a heating rate of 10°C/min to measure the second melting peak temperature Q (°C).
• the flow rate of nitrogen gas is 50 ml/min.
• the total thickness of the adhesive film 1 for metal terminals corresponds to the thickness of resin layer A.
• the thickness of the resin layer A is preferably about 10 ⁇ m or more, more preferably about 15 ⁇ m or more, even more preferably about 20 ⁇ m or more, even more preferably about 30 ⁇ m or more, even more preferably about 40 ⁇ m or more, even more preferably about 50 ⁇ m or more, and is preferably about 120 ⁇ m or less, more preferably about 100 ⁇ m or less, even more preferably 80 ⁇ m or less.
• Preferred ranges of the thickness of the resin layer A include about 10 to 120 ⁇ m, about 10 to 100 ⁇ m, about 10 to 80 ⁇ m, about 15 to 120 ⁇ m, about 15 to 100 ⁇ m, about 15 to 80 ⁇ m, about 20 to 120 ⁇ m, about 20 to 100 ⁇ m, about 20 to 80 ⁇ m, about 30 to 120 ⁇ m, about 30 to 100 ⁇ m, about 30 to 80 ⁇ m, about 40 to 120 ⁇ m, about 40 to 100 ⁇ m, about 40 to 80 ⁇ m, about 50 to 120 ⁇ m, about 50 to 100 ⁇ m, and about 50 to 80 ⁇ m.
• the thickness of the resin layer A is preferably about 55 ⁇ m or more, more preferably about 60 ⁇ m or more, and is also preferably about 100 ⁇ m or less, more preferably about 90 ⁇ m or less, with preferred ranges including about 55 to 100 ⁇ m, about 55 to 90 ⁇ m, about 60 to 100 ⁇ m, and about 60 to 90 ⁇ m.
• the thickness of each resin layer A is the above-mentioned thickness.
• the adhesive film 1 for metal terminals of the present disclosure can be configured, for example as shown in FIG. 6, to have at least a first resin layer 12a, an intermediate layer 11, and a second resin layer 12b laminated in this order.
• the first resin layer 12a is disposed on the metal terminal 2 side.
• the first resin layer 12a and the second resin layer 12b are located on the surfaces of both sides, respectively.
• the second resin layer 12b constitutes the surface on the side of the exterior material 3 for an electricity storage device, at least the second resin layer 12b is referred to as resin layer A.
• the first resin layer 12a is a layer made of resin.
• the first resin layer 12a may be formed of resin layer A, or may be formed of resin layer B different from resin layer A. Since the first resin layer 12a is disposed on the metal terminal 2 side, it preferably contains the acid-modified polyolefin described above, and is preferably formed of acid-modified polyolefin. In other words, the first resin layer 12a can be suitably formed of an acid-modified polyolefin film.
• the acid-modified polyolefin is as described for resin layer A.
• the intermediate layer 11 may be formed from a resin layer A, or may be formed from a resin layer B that is different from the resin layer A.
• resin layer B examples of the resin constituting the resin layer B include polyolefin resins, polyamide resins, polyester resins, epoxy resins, acrylic resins, fluororesins, silicone resins, phenol resins, polyetherimides, polyimides, polycarbonates, and mixtures or copolymers thereof, among which polyolefin resins are particularly preferred.
• polyolefin resins include polyolefins and acid-modified polyolefins.
• the first resin layer 12a preferably contains a polyolefin resin (i.e., has a polyolefin skeleton), preferably contains a polyolefin, and is more preferably a layer formed from a polyolefin.
• the first resin layer 12a preferably contains, among the polyolefin resins, a polyolefin or an acid-modified polyolefin, more preferably contains an acid-modified polyolefin, and is even more preferably a layer formed from an acid-modified polyolefin.
• the intermediate layer 11 preferably contains a polyolefin resin (i.e., has a polyolefin skeleton), preferably contains a polyolefin, and more preferably is a layer formed from a polyolefin.
• the polyolefin resin is preferably a polypropylene resin.
• the polyolefin is preferably polypropylene, and the acid-modified polyolefin is preferably acid-modified polypropylene.
• the resin layer B may be formed of one type of resin component alone, or may be formed of a blend polymer combining two or more types of resin components. From the viewpoint of film formability, it is preferable that the resin layer B is formed of a blend polymer combining two or more types of resin components. When using a blend polymer, it is preferable that the resin layer B has acid-modified polypropylene as the main component (a component of 50 mass% or more) and 50 mass% or less of other resins (preferably polyethylene from the viewpoint of improving flexibility).
• the resin layer B containing acid-modified polypropylene has acid-modified polypropylene as the main component (a component of 50 mass% or more) and 50 mass% or less of other resins (preferably polyethylene from the viewpoint of improving flexibility).
• the resin layer B contains acid-modified polypropylene alone as a resin.
• the polyester resin constituting the resin layer B is, for example, one that contains a polyester structure such as polyethylene terephthalate or polybutylene terephthalate.
• the polyester structure may further contain a polyether structure, and the polyether structure may have a polycondensation structure of at least one of polytetramethylene ether glycol and neopentyl glycol and terephthalic acid of a polybutylene terephthalate structure.
• the polyester structure may further contain another polyester structure, and the polyester structure may have a polycondensation structure of at least one selected from the group consisting of isophthalic acid, dodecanedioic acid, and sebacic acid and 1,4-butanediol of a polybutylene terephthalate structure.
• the melting peak temperature of resin layer B is preferably 125°C or higher, more preferably about 130°C or higher, and even more preferably about 135°C or higher.
• the melting peak temperature is, for example, 180°C or lower, preferably 175°C or lower, more preferably 170°C or lower, even more preferably about 165°C or lower, and even more preferably about 160°C or lower.
• Preferred ranges for the melting peak temperature include about 125 to 180°C, about 125 to 175°C, about 125 to 170°C, about 125 to 165°C, about 125 to 160°C, about 130 to 180°C, about 130 to 175°C, about 130 to 170°C, about 130 to 165°C, about 130 to 160°C, about 135 to 180°C, about 135 to 175°C, about 135 to 170°C, about 135 to 165°C, and about 135 to 160°C.
• the thickness of resin layer B is preferably about 10 ⁇ m or more, more preferably about 15 ⁇ m or more, even more preferably about 20 ⁇ m or more, even more preferably about 30 ⁇ m or more, even more preferably about 40 ⁇ m or more, even more preferably about 50 ⁇ m or more, even more preferably more than about 50 ⁇ m, even more preferably about 60 ⁇ m or more, and is preferably about 120 ⁇ m or less, more preferably about 100 ⁇ m or less, even more preferably 80 ⁇ m or less, even more preferably 50 ⁇ m or less.
• Preferred ranges of the thickness of the resin layer B are about 10 to 120 ⁇ m, about 10 to 100 ⁇ m, about 10 to 80 ⁇ m, about 10 to 50 ⁇ m, about 15 to 120 ⁇ m, about 15 to 100 ⁇ m, about 15 to 80 ⁇ m, about 15 to 50 ⁇ m, about 20 to 120 ⁇ m, about 20 to 100 ⁇ m, about 20 to 80 ⁇ m, about 20 to 50 ⁇ m, and about 30 to 120 ⁇ m.
• the thickness of the resin layer B is preferably about 10 ⁇ m or more, more preferably about 20 ⁇ m or more, and even more preferably about 30 ⁇ m or more.
• the thickness of the resin layer B is preferably about 50 ⁇ m or more, more preferably more than about 50 ⁇ m.
• the thickness of the resin layer B is preferably about 120 ⁇ m or less, more preferably about 110 ⁇ m or less, and even more preferably 100 ⁇ m or less.
• the thickness of the resin layer B is preferably about 50 ⁇ m or less, or about 30 ⁇ m or less.
• Preferred ranges for the thickness of the resin layer B include about 10 to 120 ⁇ m, about 10 to 110 ⁇ m, about 10 to 100 ⁇ m, about 10 to 50 ⁇ m, about 10 to 30 ⁇ m, about 20 to 120 ⁇ m, about 20 to 110 ⁇ m, about 20 to 100 ⁇ m, about 20 to 50 ⁇ m, about 20 to 30 ⁇ m, about 30 to 120 ⁇ m, about 30 to 110 ⁇ m, about 30 to 100 ⁇ m, about 30 to 50 ⁇ m, about 50 to 120 ⁇ m, about 50 to 110 ⁇ m, about 50 to 100 ⁇ m, more than 50 ⁇ m and up to about 120 ⁇ m, more than 50 ⁇ m and up to about 110 ⁇ m, and more than 50 ⁇ m and up to about 100 ⁇ m.
• resin layer B may contain known additives (such as the above-mentioned fillers and pigments) just like resin layer A.
• the types and amounts of fillers and pigments to be added are the same as those for resin layer A.
• the total thickness of the adhesive film 1 for metal terminals is, for example, about 50 ⁇ m or more, preferably about 80 ⁇ m or more, more preferably about 90 ⁇ m or more, and even more preferably about 100 ⁇ m or more.
• the total thickness of the adhesive film 1 for metal terminals of the present disclosure is about 500 ⁇ m or less, preferably about 300 ⁇ m or less, more preferably about 250 ⁇ m or less, even more preferably 200 ⁇ m or less, and even more preferably 180 ⁇ m or less.
• Preferred ranges of the total thickness of the adhesive film 1 for metal terminals of the present disclosure include about 50 to 500 ⁇ m, about 50 to 300 ⁇ m, about 50 to 250 ⁇ m, about 50 to 200 ⁇ m, about 50 to 180 ⁇ m, about 80 to 500 ⁇ m, about 80 to 300 ⁇ m, about 80 to 250 ⁇ m, about 80 to 200 ⁇ m, about 80 to 180 ⁇ m, about 90 to 500 ⁇ m, about 90 to 300 ⁇ m, about 90 to 250 ⁇ m, about 90 to 200 ⁇ m, about 90 to 180 ⁇ m, about 100 to 500 ⁇ m, about 100 to 300 ⁇ m, about 100 to 250 ⁇ m, about 100 to 200 ⁇ m, and about 100 to 180 ⁇ m.
• the total thickness is preferably about 60 to 100 ⁇ m, and when it is used in a relatively large power storage device for a power storage system or vehicle, the total thickness is preferably about 100 to 200 ⁇ m.
• the adhesive film 1 for metal terminals of the present disclosure has an adhesive strength (peel strength in a 25°C environment) with the heat-sealable resin layer of the exterior material, measured by the following method, of preferably about 80 N/15 mm or more, more preferably about 90 N/15 mm or more, and even more preferably about 100 N/15 mm or more, and the upper limit of the adhesive strength (in a 25°C environment) is usually about 140 N/15 mm or less, with preferred ranges being about 80 to 140 N/15 mm, about 90 to 140 N/15 mm, and about 100 to 140 N/15 mm.
• the adhesive film 1 for metal terminals of the present disclosure has an adhesive strength (peel strength in a 60°C environment) with the heat-sealable resin layer of the exterior material, measured by the following method, of preferably about 60 N/15 mm or more, more preferably about 70 N/15 mm or more, and even more preferably about 80 N/15 mm or more, and the upper limit of the adhesive strength (in a 60°C environment) is usually about 120 N/15 mm or less, with preferred ranges being about 60 to 120 N/15 mm, about 70 to 120 N/15 mm, and about 80 to 120 N/15 mm.
• peel strength in a 60°C environment measured by the following method, of preferably about 60 N/15 mm or more, more preferably about 70 N/15 mm or more, and even more preferably about 80 N/15 mm or more
• the upper limit of the adhesive strength (in a 60°C environment) is usually about 120 N/15 mm or less, with preferred ranges being about 60 to 120 N/15 mm, about 70 to 120 N/15 mm
• an exterior material for a power storage device (hereinafter, sometimes simply referred to as "exterior material") is prepared by the following procedure.
• a two-liquid urethane adhesive a polyol compound and an aromatic isocyanate compound
• the adhesive layer and a polyethylene terephthalate film are laminated on the nylon film to prepare a base layer.
• a two-liquid urethane adhesive (a polyol compound and an aromatic isocyanate compound) is applied on one surface of a barrier layer consisting of an aluminum alloy foil, and an adhesive layer (thickness 3 ⁇ m) is formed on the aluminum alloy foil.
• the adhesive layer and the substrate layer with the nylon film side as the adhesive surface are laminated on the aluminum alloy foil, and then aging treatment is performed to produce a substrate layer/adhesive layer/barrier layer laminate.
• an adhesive layer (40 ⁇ m thick, arranged on the metal layer side) made of maleic anhydride-modified polypropylene resin and a heat-sealable resin layer (40 ⁇ m crystalline lamella thickness, innermost layer) made of random polypropylene resin are co-extruded on the barrier layer of the laminate to laminate the adhesive layer/heat-sealable resin layer on the barrier layer, thereby obtaining an exterior material for a storage battery device in which the substrate layer, adhesive layer, barrier layer, adhesive layer, and heat-sealable resin layer are laminated in this order.
• the crystalline lamella thickness of the heat-sealable resin layer of the obtained exterior material for a storage battery device is 5.0 to 9.0 nm.
• a piece of aluminum foil (JIS H4160:1994 A8079H-O) with an MD of 40 mm, TD of 22.5 mm and thickness of 400 ⁇ m is prepared as the metal terminal 2.
• the adhesive film 1 is cut to a length of 45 mm and a width of 20 mm.
• the metal terminal is sandwiched between two adhesive films to obtain an adhesive film/metal terminal/adhesive film laminate.
• the MD and TD of the metal terminal are aligned with the length and width directions of the adhesive film, respectively, and the metal terminal and adhesive film are laminated so that their centers are aligned (see Figure 9(a)).
• the first resin layer of the adhesive film is also arranged on the metal terminal side.
• the laminate is sandwiched between two polytetrafluoroethylene films (PTFE films, thickness 100 ⁇ m), and heated under conditions of a temperature of 200 ° C., a surface pressure of 0.25 MPa, and 16 seconds (once), to heat-seal the first resin layer of the adhesive film to the metal terminal to produce a metal terminal with an adhesive film (see FIG. 9 (b)).
• PTFE films polytetrafluoroethylene films
• FIG. 9 (b) the metal terminal is sandwiched between the adhesive films, so that the periphery of the metal terminal is covered with the adhesive film, and a portion in which the two adhesive films are heat-sealed to each other is formed.
• the exterior material is cut to a size of TD 60 mm and MD 200 mm, and as shown in the schematic diagram of FIG. 10, the exterior material is placed facing each other with the heat-sealable resin layer of the exterior material facing inside, and the obtained laminate is sandwiched between the opposing heat-sealable resin layers (see FIG. 10 (a)).
• the exterior material is laminated so that the MD and TD correspond to the width direction and length direction of the laminate, respectively.
• a heat seal tester is used to perform heat sealing (see the shaded area S in FIG. 10(b)) at a width of 7 mm (7 mm in the y-axis direction in FIG.
• the adhesive film for metal terminals of the present disclosure preferably has fine irregularities on at least one surface of the outermost layer. This can further improve adhesion to the heat-sealable resin layer 35 of the exterior material for the power storage device or to the metal terminal.
• Methods for forming fine irregularities on the surface of the outermost layer of the adhesive film for metal terminals include a method of adding additives such as fine particles to the outermost layer, and a method of applying a cooling roll having an irregular surface to the outermost layer to form the surface.
• the ten-point average roughness of the surface of the outermost layer is preferably about 0.1 ⁇ m or more, more preferably about 0.2 ⁇ m or more, and is also preferably about 35 ⁇ m or less, more preferably about 10 ⁇ m or less, and preferred ranges include about 0.1 to 35 ⁇ m, about 0.1 to 10 ⁇ m, about 0.2 to 35 ⁇ m, and about 0.2 to 10 ⁇ m.
• the ten-point average roughness is a value measured by a method conforming to the provisions of JIS B0601:1994.
• the adhesive film 1 for metal terminals of the present disclosure is preferably formed from a polyolefin resin.
• the resin components contained in the adhesive film 1 for metal terminals of the present disclosure are preferably only acid-modified polyolefins, or only acid-modified polyolefins and polyolefins.
• the preferred acid-modified polyolefins and polyolefins are as described for resin layer A and resin layer B.
• the adhesive film 1 for metal terminals of the present disclosure is preferably composed of a laminate having a first resin layer 12a, an intermediate layer 11, and a second resin layer 12b in this order.
• a preferred embodiment of the adhesive film 1 for metal terminals of the present disclosure will be described in detail using an example in which the adhesive film 1 for metal terminals of the present disclosure is composed of a laminate having at least a first resin layer 12a, an intermediate layer 11, and a second resin layer 12b in this order, and the second resin layer 12b is resin layer A.
• the adhesive film 1 for metal terminals of the present disclosure When the adhesive film 1 for metal terminals of the present disclosure is placed between the metal terminal 2 of the electricity storage device 10 and the exterior material 3 for the electricity storage device, the surface of the metal terminal 2 made of metal and the heat-sealable resin layer 35 (a layer formed of a heat-sealable resin such as polyolefin) of the exterior material 3 for the electricity storage device are bonded via the adhesive film 1 for metal terminals.
• the first resin layer 12a of the adhesive film 1 for metal terminals is placed on the metal terminal 2 side, and the second resin layer 12b is placed on the exterior material 3 for the electricity storage device, with the first resin layer 12a in close contact with the metal terminal 2 and the second resin layer 12b in close contact with the heat-sealable resin layer 35 of the exterior material 3 for the electricity storage device.
• the first resin layer 12a may be a single layer or a multi-layer structure (multi-layer).
• the second resin layer 12b may be a single layer or a multi-layer structure (multi-layer).
• the adhesive film 1 for metal terminal comprises a first resin layer 12a on one side of an intermediate layer 11, and a second resin layer 12b on the other side.
• the first resin layer 12a is disposed on the metal terminal 2 side.
• the second resin layer 12b is disposed on the exterior material 3 for an electrical storage device.
• the first resin layer 12a and the second resin layer 12b are located on the surfaces of both sides, respectively.
• the second resin layer 12b is formed from the aforementioned resin layer A.
• the first resin layer 12a may be formed from the aforementioned resin layer A or may be formed from the aforementioned resin layer B.
• the first resin layer 12a and the second resin layer 12b can each be formed, for example, from a resin film.
• a preformed resin film may be used as the first resin layer 12a and the second resin layer 12b, respectively.
• the resins forming the first resin layer 12a and the second resin layer 12b may each be formed into a film on the surface of the intermediate layer 11 or the like by extrusion molding or coating, and used as the first resin layer 12a and the second resin layer 12b formed from the resin film.
• the first resin layer 12a arranged on the metal terminal 2 side preferably contains an acid-modified polyolefin as a main component, and even more preferably contains an acid-modified polypropylene as a main component.
• the main component means that the content of the resin components contained in the first resin layer 12a is, for example, 50% by mass or more, preferably 60% by mass or more, more preferably 70% by mass or more, even more preferably 80% by mass or more, even more preferably 90% by mass or more, even more preferably 95% by mass or more, even more preferably 98% by mass or more, and even more preferably 99% by mass or more.
• the first resin layer 12a containing acid-modified polypropylene as a main component means that the content of acid-modified polypropylene among the resin components contained in the first resin layer 12a is, for example, 50% by mass or more, preferably 60% by mass or more, more preferably 70% by mass or more, even more preferably 80% by mass or more, even more preferably 90% by mass or more, even more preferably 95% by mass or more, even more preferably 98% by mass or more, and even more preferably 99% by mass or more.
• the second resin layer 12b preferably contains a polyolefin-based resin (i.e., has a polyolefin skeleton), preferably contains a polyolefin, and is more preferably a layer formed of a polyolefin.
• the second resin layer 12b preferably contains, among the polyolefin-based resins, a polyolefin or an acid-modified polyolefin, more preferably contains a polyolefin (polyolefin that is not acid-modified), and is even more preferably a layer formed of a polyolefin (polyolefin that is not acid-modified).
• the polyolefin-based resin is preferably a polypropylene-based resin.
• the polyolefin is preferably polypropylene, and the acid-modified polyolefin is preferably polypropylene.
• the second resin layer 12b (resin layer A) arranged on the side of the exterior material 3 for the electric storage device more preferably contains polyolefin as a main component, and even more preferably contains polypropylene as a main component.
• the main component means that the content of the resin components contained in the second resin layer 12b is, for example, 50% by mass or more, preferably 60% by mass or more, more preferably 70% by mass or more, even more preferably 80% by mass or more, even more preferably 90% by mass or more, even more preferably 95% by mass or more, even more preferably 98% by mass or more, even more preferably 99% by mass or more.
• the second resin layer 12b containing polypropylene as a main component means that the content of polypropylene among the resin components contained in the second resin layer 12b is, for example, 50% by mass or more, preferably 60% by mass or more, more preferably 70% by mass or more, even more preferably 80% by mass or more, even more preferably 90% by mass or more, even more preferably 95% by mass or more, even more preferably 98% by mass or more, even more preferably 99% by mass or more.
• the melting peak temperature of the second resin layer 12b is preferably 110°C or higher, more preferably about 120°C or higher, and even more preferably about 130°C or higher. From a similar perspective, the melting peak temperature is, for example, 200°C or lower, preferably 190°C or lower, more preferably 180°C or lower, even more preferably about 170°C or lower, and even more preferably about 160°C or lower.
• Preferred ranges for the melting peak temperature include about 110 to 200°C, about 110 to 190°C, about 110 to 180°C, about 110 to 170°C, about 110 to 160°C, about 120 to 200°C, about 120 to 190°C, about 120 to 180°C, about 120 to 170°C, about 120 to 160°C, about 130 to 200°C, about 130 to 190°C, about 130 to 180°C, about 130 to 170°C, and about 130 to 160°C.
• the thickness of the first resin layer 12a is preferably at least about 10 ⁇ m, more preferably at least about 15 ⁇ m, even more preferably at least about 20 ⁇ m, and is preferably no more than about 120 ⁇ m, more preferably no more than about 100 ⁇ m, even more preferably no more than 80 ⁇ m.
• Preferred ranges for the thickness of the first resin layer 12a include about 10 to 120 ⁇ m, about 10 to 100 ⁇ m, about 10 to 80 ⁇ m, about 15 to 120 ⁇ m, about 15 to 100 ⁇ m, about 15 to 80 ⁇ m, about 20 to 120 ⁇ m, about 20 to 100 ⁇ m, and about 20 to 80 ⁇ m.
• the thickness of the second resin layer 12b is preferably at least about 10 ⁇ m, more preferably at least about 15 ⁇ m, and even more preferably at least about 20 ⁇ m, and is preferably no more than about 120 ⁇ m, more preferably no more than about 100 ⁇ m, and even more preferably no more than 80 ⁇ m.
• Preferred ranges for the thickness of the second resin layer 12b include about 10 to 120 ⁇ m, about 10 to 100 ⁇ m, about 10 to 80 ⁇ m, about 15 to 120 ⁇ m, about 15 to 100 ⁇ m, about 15 to 80 ⁇ m, about 20 to 120 ⁇ m, about 20 to 100 ⁇ m, and about 20 to 80 ⁇ m.
• a colorant may be blended into at least one of the first resin layer 12a and the second resin layer 12b.
• Specific examples of colorants include those exemplified for the intermediate layer 11 described below.
• the intermediate layer 11 is a layer that functions as a support for the adhesive film for metal terminal 1 .
• the intermediate layer 11 may be formed from the aforementioned resin layer A, or may be formed from the aforementioned resin layer B.
• the intermediate layer 11 can be formed, for example, from a resin film.
• a pre-formed resin film may be used as the intermediate layer 11 when the intermediate layer 11 is laminated with the first resin layer 12a or the like to manufacture the adhesive film for metal terminal 1 of the present disclosure.
• the resin forming the intermediate layer 11 may be formed into a film on the surface of the first resin layer 12a or the like by extrusion molding, coating, or the like, to form the intermediate layer 11 from a resin film.
• the material forming the intermediate layer 11 is not particularly limited.
• materials forming the intermediate layer 11 include polyolefin resins, polyamide resins, polyester resins, epoxy resins, acrylic resins, fluororesins, silicone resins, phenolic resins, polyetherimides, polyimides, polycarbonates, and mixtures and copolymers thereof.
• polyolefin resins are particularly preferred.
• the material forming the intermediate layer 11 is preferably a resin containing a polyolefin skeleton, such as polyolefin or acid-modified polyolefin. Whether the resin constituting the intermediate layer 11 contains a polyolefin skeleton can be analyzed, for example, by infrared spectroscopy, gas chromatography mass spectrometry, or the like.
• the intermediate layer 11 preferably contains a polyolefin resin, more preferably contains a polyolefin, and more preferably is a layer formed of a polyolefin.
• the layer formed of a polyolefin may be a stretched polyolefin film or an unstretched polyolefin film, but is preferably an unstretched polyolefin film.
• polyolefin examples include polyethylene such as low-density polyethylene, medium-density polyethylene, high-density polyethylene, and linear low-density polyethylene; crystalline or amorphous polypropylene such as homopolypropylene, block copolymers of polypropylene (e.g., block copolymers of propylene and ethylene), and random copolymers of polypropylene (e.g., random copolymers of propylene and ethylene); and ethylene-butene-propylene terpolymers.
• polyethylene and polypropylene are preferred, and polypropylene is more preferred.
• the intermediate layer 11 preferably contains homopolypropylene, more preferably is formed of homopolypropylene, and even more preferably is an unstretched homopolypropylene film.
• polyamides include aliphatic polyamides such as nylon 6, nylon 66, nylon 610, nylon 12, nylon 46, and copolymers of nylon 6 and nylon 66; hexamethylenediamine-isophthalic acid-terephthalic acid copolymer polyamides such as nylon 6I, nylon 6T, nylon 6IT, and nylon 6I6T (I represents isophthalic acid and T represents terephthalic acid) which contain structural units derived from terephthalic acid and/or isophthalic acid, and aromatic polyamides such as polymetaxylylene adipamide (MXD6); alicyclic polyamides such as polyaminomethylcyclohexyl adipamide (PACM6); polyamides copolymerized with lactam components or isocyanate components such as 4,4'-diphenylmethane diisocyanate; polyesteramide copolymers and polyetheresteramide copolymers which are copolymers of copolymerized polyamides with polyesters
• polyesters include polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polybutylene naphthalate, polyethylene isophthalate, copolymer polyesters whose repeating units are mainly ethylene terephthalate, and copolymer polyesters whose repeating units are mainly butylene terephthalate.
• copolymer polyesters whose repeating units are mainly ethylene terephthalate include copolymer polyesters in which ethylene terephthalate is the main repeating unit and is polymerized with ethylene isophthalate (hereinafter abbreviated as polyethylene (terephthalate/isophthalate)), polyethylene (terephthalate/isophthalate), polyethylene (terephthalate/adipate), polyethylene (terephthalate/sodium sulfoisophthalate), polyethylene (terephthalate/sodium isophthalate), polyethylene (terephthalate/phenyl-dicarboxylate), and polyethylene (terephthalate/decanedicarboxylate).
• polyethylene (terephthalate/isophthalate) polyethylene (terephthalate/isophthalate)
• polyethylene (terephthalate/isophthalate) polyethylene (terephthalate/isophthalate)
• polyethylene (terephthalate/adipate) polyethylene (terephthalate/
• copolymer polyesters containing butylene terephthalate as the main repeating unit include copolymer polyesters in which butylene terephthalate is the main repeating unit and is polymerized with butylene isophthalate (hereinafter abbreviated as polybutylene (terephthalate/isophthalate)), polybutylene (terephthalate/adipate), polybutylene (terephthalate/sebacate), polybutylene (terephthalate/decanedicarboxylate), polybutylene naphthalate, etc. These polyesters may be used alone or in combination of two or more.
• the intermediate layer 11 may also be formed of a nonwoven fabric made of the above-mentioned resin.
• the intermediate layer 11 is a nonwoven fabric, it is preferable that the intermediate layer 11 is composed of the above-mentioned polyolefin resin, polyamide resin, polyester resin, etc.
• the melting peak temperature of the intermediate layer 11 is preferably 120°C or higher, more preferably about 130°C or higher, and even more preferably about 140°C or higher. From a similar perspective, the melting peak temperature is, for example, 210°C or lower, preferably 200°C or lower, more preferably 190°C or lower, even more preferably about 180°C or lower, and even more preferably about 170°C or lower.
• Preferred ranges for the melting peak temperature include about 120 to 210°C, about 120 to 200°C, about 120 to 190°C, about 120 to 180°C, about 120 to 170°C, about 130 to 210°C, about 130 to 200°C, about 130 to 190°C, about 130 to 180°C, about 130 to 170°C, about 140 to 210°C, about 140 to 200°C, about 140 to 190°C, about 140 to 180°C, and about 140 to 170°C.
• the intermediate layer 11 may be a single layer or a multi-layer structure (multi-layer).
• the intermediate layer 11 can be a layer containing the colorant.
• the light transmittance can be adjusted by selecting a resin with low transparency. If the intermediate layer 11 is a film, a colored film or a film with low transparency can be used. If the intermediate layer 11 is a nonwoven fabric, a nonwoven fabric using fibers or a binder containing a colorant, or a nonwoven fabric with low transparency can be used.
• the colorant is not particularly limited, and a colorant capable of coloring the intermediate layer 11 can be suitably used.
• colorants include pigments.
• Various inorganic or organic pigments can be used as the pigment.
• pigments include the carbon (carbon, graphite), silica, titanium oxide, iron oxide, zinc oxide, magnesium oxide, and calcium oxide exemplified as the filler described above, as well as inorganic oxides such as titanium nitride, zirconia black, copper oxide, cobalt oxide, and barium sulfate, and organic pigments such as quinacridone pigments, polyazo pigments, and isoindolinone pigments.
• Carbon (carbon, graphite) is a material that is generally used inside an electricity storage device, and there is no risk of it dissolving in the electrolyte. In addition, it has a large coloring effect, and a sufficient coloring effect can be obtained with an amount added that does not inhibit adhesion, and it does not melt with heat, and the apparent melt viscosity of the added resin can be increased. Furthermore, it is possible to prevent the pressurized portion from becoming thin during heat fusion (heat sealing), thereby providing excellent sealing between the exterior material for the electricity storage device and the metal terminal.
• the color of the colorant is preferably black, gray, or white.
• the surface of the intermediate layer 11 may be subjected to a known adhesion enhancing method such as corona discharge treatment, ozone treatment, or plasma treatment, if necessary.
• the thickness of the intermediate layer 11 is preferably at least about 20 ⁇ m, more preferably at least about 30 ⁇ m, and even more preferably at least about 40 ⁇ m, and is preferably at most about 120 ⁇ m, more preferably at most about 110 ⁇ m, and even more preferably at most 100 ⁇ m.
• Preferred ranges for the thickness of the intermediate layer 11 include about 20 to 120 ⁇ m, about 20 to 110 ⁇ m, about 20 to 100 ⁇ m, about 30 to 120 ⁇ m, about 30 to 110 ⁇ m, about 30 to 100 ⁇ m, about 40 to 120 ⁇ m, about 40 to 110 ⁇ m, and about 40 to 100 ⁇ m.
• the ratio of the thickness of the intermediate layer 11 to the total thickness of the first resin layer 12a and the second resin layer 12b is preferably about 0.3 or more, more preferably about 0.4 or more, and also preferably about 1.0 or less, more preferably about 0.8 or less, with preferred ranges being about 0.3 to 1.0, about 0.3 to 0.8, about 0.4 to 1.0, and about 0.4 to 0.8.
• the ratio is preferably about 0.55 or more, more preferably about 0.60 or more, and also preferably about 1.0 or less, more preferably about 0.9 or less, with preferred ranges being about 0.55 to 1.0, about 0.55 to 0.9, about 0.60 to 1.0, and about 0.60 to 0.9.
• the ratio of the total thickness of the first resin layer 12a and the second resin layer 12b is preferably about 30 to 80%, and more preferably about 50 to 70%.
• the adhesive film 1 for metal terminals of the present disclosure can be manufactured, for example, by laminating a first resin layer 12a and a second resin layer 12b on both surfaces of an intermediate layer 11.
• the intermediate layer 11 can be laminated with the first resin layer 12a and the second resin layer 12b by a known method such as an extrusion lamination method, a T-die method, an inflation method, or a thermal lamination method.
• the method of interposing the adhesive film 1 for metal terminals between the metal terminal 2 and the exterior material 3 for the electricity storage device is not particularly limited, and for example, as shown in Figures 1 to 3, the adhesive film 1 for metal terminals may be wrapped around the metal terminal 2 in the portion where the metal terminal 2 is sandwiched by the exterior material 3 for the electricity storage device.
• the adhesive film 1 for metal terminals may be arranged on both sides of the metal terminal 2 so as to cross the two metal terminals 2 in the portion where the metal terminal 2 is sandwiched by the exterior material 3 for the electricity storage device.
• the adhesion promoter layer 13 is a layer that is provided as necessary for the purpose of firmly adhering the intermediate layer 11 to the first resin layer 12a, and between the intermediate layer 11 and the second resin layer 12b (see FIG. 7).
• the adhesion promoter layer 13 may be provided on only one side between the intermediate layer 11 and the first resin layer 12a and between the intermediate layer 11 and the second resin layer 12b, or on both sides.
• the adhesion promoter layer 13 can be formed using known adhesion promoters such as isocyanate-based, polyethyleneimine-based, polyester-based, polyurethane-based, polybutadiene-based, etc. From the viewpoint of obtaining strong adhesion strength, it is preferable that it is formed using an isocyanate-based adhesion promoter.
• an isocyanate-based adhesion promoter one consisting of an isocyanate component selected from triisocyanate monomer and polymeric MDI has excellent laminate strength and suffers little deterioration in laminate strength at high temperatures.
• an adhesion promoter made of triphenylmethane-4,4',4"-triisocyanate, which is a triisocyanate monomer, or polymethylene polyphenyl polyisocyanate, which is a polymeric MDI (NCO content of about 30%, viscosity of 200 to 700 mPa ⁇ s). It is also preferable to form the adhesive using triisocyanate monomer tris(p-isocyanatephenyl)thiophosphate, or a two-component curing adhesion promoter that uses a polyethyleneimine system as the main agent and polycarbodiimide as the crosslinking agent.
• the adhesion promoter layer 13 can be formed by coating and drying using a known coating method such as bar coating, roll coating, gravure coating, etc.
• the amount of the adhesion promoter to be applied is about 20 to 100 mg/m 2 , preferably about 40 to 60 mg/m 2 , in the case of an adhesion promoter made of triisocyanate, about 40 to 150 mg/m 2 , preferably about 60 to 100 mg/m 2 , in the case of an adhesion promoter made of polymeric MDI, and about 5 to 50 mg/m 2 , preferably about 10 to 30 mg/m 2 , in the case of a two-liquid curing type adhesion promoter with a polyethyleneimine system as the main agent and a polycarbodiimide as the crosslinking agent.
• the triisocyanate monomer is a monomer having three isocyanate groups in one molecule
• the polymeric MDI is a mixture of MDI and MDI oligomers polymerized from MDI, and is represented
• first resin layer 12a and the intermediate layer 11 are in contact with each other, and that the second resin layer 12b and the intermediate layer 11 are in contact with each other.
• preferred laminated structures of the adhesive film 1 for metal terminals of the present disclosure include a three-layer structure in which a first resin layer formed from acid-modified polypropylene/a substrate formed from polypropylene/a second resin layer formed from acid-modified polypropylene are laminated in this order; and a three-layer structure in which a first resin layer formed from acid-modified polypropylene/a substrate formed from polypropylene/a second resin layer formed from polypropylene are laminated in this order.
• the latter three-layer structure is particularly preferred in terms of adhesion between the heat-sealable resin layer 35 and the second resin layer 12b of the exterior material 3 for electrical storage devices.
• the adhesive film 1 for metal terminals of the present disclosure is used by being interposed between a metal terminal 2 and an exterior material 3 for an electricity storage device.
• the metal terminal 2 (tab) is a conductive member electrically connected to an electrode (positive electrode or negative electrode) of an electricity storage device element 4, and is made of a metal material.
• the metal material constituting the metal terminal 2 is not particularly limited, and examples thereof include aluminum, nickel, copper, and the like.
• the metal terminal 2 connected to the positive electrode of a lithium ion electricity storage device is usually made of aluminum, etc.
• the metal terminal 2 connected to the negative electrode of a lithium ion electricity storage device is usually made of copper, nickel, etc.
• the surface of the metal terminal 2 is preferably subjected to a chemical conversion treatment in order to enhance resistance to electrolyte.
• a chemical conversion treatment include known methods for forming a corrosion-resistant film using phosphates, chromates, fluorides, triazine thiol compounds, etc.
• a phosphate chromate treatment using a compound consisting of three components: phenolic resin, chromium (III) fluoride compound, and phosphoric acid is preferable.
• the size of the metal terminal 2 may be set appropriately depending on the size of the electricity storage device to be used.
• the thickness of the metal terminal 2 is preferably about 50 to 1000 ⁇ m, more preferably about 70 to 800 ⁇ m.
• the length of the metal terminal 2 is preferably about 1 to 200 mm, more preferably about 3 to 150 mm.
• the width of the metal terminal 2 is preferably about 1 to 200 mm, more preferably about 3 to 150 mm.
• the exterior material 3 for an electric storage device may have a laminated structure including at least a base material layer 31, a barrier layer 33, and a heat-sealable resin layer 35 in this order.
• FIG. 8 shows an example of a cross-sectional structure of the exterior material 3 for an electric storage device, in which the base material layer 31, an adhesive layer 32 provided as needed, a barrier layer 33, an adhesive layer 34 provided as needed, and a heat-sealable resin layer 35 are laminated in this order.
• the base material layer 31 is the outer layer
• the heat-sealable resin layer 35 is the innermost layer.
• FIGS. 1 to 3 show the electric storage device 10 in the case where an embossed type exterior material 3 for an electric storage device formed by embossing or the like is used, but the exterior material 3 for an electric storage device may be an unformed pouch type.
• the pouch type includes three-sided seal, four-sided seal, pillow type, etc., and any type may be used.
• the thickness of the laminate constituting the exterior material 3 for the electric storage device is not particularly limited, but from the viewpoint of cost reduction, energy density improvement, etc., the upper limit is, for example, about 190 ⁇ m or less, preferably about 180 ⁇ m or less, about 160 ⁇ m or less, about 155 ⁇ m or less, about 140 ⁇ m or less, about 130 ⁇ m or less, and about 120 ⁇ m or less. From the viewpoint of maintaining the function of the exterior material 3 for the electric storage device to protect the electric storage device element 4, the lower limit is preferably about 35 ⁇ m or more, about 45 ⁇ m or more, about 60 ⁇ m or more, and about 80 ⁇ m or more.
• Preferred ranges are, for example, about 35 to 190 ⁇ m, about 35 to 180 ⁇ m, and about 35 to 160 ⁇ m. degree, about 35 to 155 ⁇ m, about 35 to 140 ⁇ m, about 35 to 130 ⁇ m, about 35 to 120 ⁇ m, about 45 to 190 ⁇ m, about 45 to 180 ⁇ m, 45 ⁇ 160 ⁇ m, 45-155 ⁇ m, 45-140 ⁇ m, 45-130 ⁇ m, 45-120 ⁇ m, 60-190 ⁇ m, 60-180 ⁇ m
• Examples include about 60 to 160 ⁇ m, about 60 to 155 ⁇ m, about 60 to 140 ⁇ m, about 60 to 130 ⁇ m, about 60 to 120 ⁇ m, about 80 to 190 ⁇ m, about 80 to 180 ⁇ m, about 80 to 160 ⁇ m, about 80 to 155 ⁇ m, about 80 to 140 ⁇ m, about 80 to 130 ⁇ m, and about 80 to 120 ⁇ m.
• the base material layer 31 is a layer that functions as a base material of the electrical storage device packaging material, and is a layer that forms the outermost layer side.
• the material forming the base layer 31 is not particularly limited, as long as it has insulating properties.
• materials forming the base layer 31 include polyester, polyamide, epoxy, acrylic resin, fluororesin, polyurethane, silicone resin, phenol, polyetherimide, polyimide, and mixtures and copolymers thereof.
• Polyesters such as polyethylene terephthalate and polybutylene terephthalate have the advantage of being highly resistant to electrolyte and being less susceptible to whitening due to adhesion of electrolyte, and are therefore preferably used as materials for forming the base layer 31.
• polyamide film has excellent stretchability and can prevent whitening due to resin cracking of the base layer 31 during molding, and is therefore preferably used as materials for forming the base layer 31.
• the substrate layer 31 may be formed of a uniaxially or biaxially stretched resin film, or may be formed of an unstretched resin film. Among them, uniaxially or biaxially stretched resin films, especially biaxially stretched resin films, are preferably used as the substrate layer 31 because their heat resistance is improved by oriented crystallization.
• the resin film forming the base layer 31 is preferably nylon or polyester, and more preferably biaxially oriented nylon or biaxially oriented polyester.
• the base layer 31 can be made by laminating resin films of different materials in order to improve pinhole resistance and insulation when used as a package for an electricity storage device.
• resin films of different materials include a multi-layer structure in which a polyester film is laminated with a nylon film, or a multi-layer structure in which biaxially oriented polyester is laminated with a biaxially oriented nylon.
• the resin films may be bonded via an adhesive, or may be laminated directly without an adhesive.
• bonding without an adhesive examples include a method of bonding in a hot melt state, such as co-extrusion, sand lamination, or thermal lamination.
• the base layer 31 may be made low-friction to improve formability.
• the base layer 31 low-friction there are no particular limitations on the coefficient of friction of its surface, but an example of this is 1.0 or less.
• Examples of ways to make the base layer 31 low-friction include matte treatment, forming a thin layer of a slip agent, and combinations of these.
• the thickness of the base layer 31 is, for example, about 10 to 50 ⁇ m, and preferably about 15 to 30 ⁇ m.
• the adhesive layer 32 is a layer that is disposed on the base material layer 31 as necessary in order to impart adhesion to the base material layer 31. That is, the adhesive layer 32 is provided between the base material layer 31 and the barrier layer 33.
• the adhesive layer 32 is formed from an adhesive capable of bonding the base layer 31 and the barrier layer 33.
• the adhesive used to form the adhesive layer 32 may be a two-component curing adhesive or a one-component curing adhesive.
• the resin component of the adhesive that can be used to form the adhesive layer 32 is preferably a polyurethane-based two-component curing adhesive; polyamide, polyester, or a blend resin of these with modified polyolefin, from the viewpoint of excellent ductility, durability under high humidity conditions, yellowing prevention, and thermal degradation prevention during heat sealing, and effectively suppressing the decrease in laminate strength between the base layer 31 and the barrier layer 33 and preventing the occurrence of delamination.
• the adhesive layer 32 may be multi-layered with different adhesive components.
• the adhesive layer 32 is multi-layered with different adhesive components, it is preferable to select a resin with excellent adhesion to the base layer 31 as the adhesive component arranged on the base layer 31 side, and an adhesive component with excellent adhesion to the barrier layer 33 as the adhesive component arranged on the barrier layer 33 side, from the viewpoint of improving the laminate strength between the base layer 31 and the barrier layer 33.
• the adhesive component arranged on the barrier layer 33 side is preferably an acid-modified polyolefin, a metal-modified polyolefin, a mixed resin of polyester and acid-modified polyolefin, a resin containing a copolymerized polyester, etc.
• the thickness of the adhesive layer 32 is, for example, about 2 to 50 ⁇ m, and preferably about 3 to 25 ⁇ m.
• the barrier layer 33 is a layer that has a function of preventing water vapor, oxygen, light, and the like from penetrating into the electrical storage device in addition to improving the strength of the electrical storage device exterior material.
• the barrier layer 33 is preferably a metal layer, that is, a layer formed of a metal. Specific examples of the metal constituting the barrier layer 33 include aluminum, stainless steel, and titanium, and preferably aluminum.
• the barrier layer 33 can be formed, for example, of a metal foil, a metal vapor deposition film, an inorganic oxide vapor deposition film, a carbon-containing inorganic oxide vapor deposition film, or a film provided with these vapor deposition films, and is preferably formed of a metal foil, and more preferably formed of an aluminum foil.
• the barrier layer is more preferably formed from a soft aluminum foil such as annealed aluminum (JIS H4160:1994 A8021H-O, JIS H4160:1994 A8079H-O, JIS H4000:2014 A8021P-O, JIS H4000:2014 A8079P-O).
• a soft aluminum foil such as annealed aluminum
• the thickness of the barrier layer 33 is preferably about 10 to 200 ⁇ m, more preferably about 20 to 100 ⁇ m, about 20 to 45 ⁇ m, about 45 to 65 ⁇ m, or about 65 to 85 ⁇ m, from the viewpoint of making the exterior material for the power storage device thinner while making it difficult for pinholes to occur during molding.
• barrier layer 33 it is preferable that at least one surface, and preferably both surfaces, of the barrier layer 33 are chemically treated to stabilize adhesion and prevent dissolution and corrosion.
• chemical treatment refers to a process for forming a corrosion-resistant film on the surface of the barrier layer.
• the adhesive layer 34 is a layer that is provided, if necessary, between the barrier layer 33 and the heat-sealable resin layer 35 in order to firmly bond the heat-sealable resin layer 35 .
• the adhesive layer 34 is formed from an adhesive capable of bonding the barrier layer 33 and the heat-sealable resin layer 35.
• the composition of the adhesive used to form the adhesive layer is not particularly limited, but examples include a resin composition containing an acid-modified polyolefin. Examples of acid-modified polyolefins include the same ones exemplified for the first resin layer 12a and the second resin layer 12b.
• the thickness of the adhesive layer 34 is, for example, about 1 to 40 ⁇ m, and preferably about 2 to 30 ⁇ m.
• the heat-sealable resin layer 35 corresponds to the innermost layer, and is a layer in which the heat-sealable resin layers are heat-sealed to each other to seal the electricity storage device elements when the electricity storage device is assembled.
• the heat-sealable resin layer 35 is disposed on the outermost surface on the electricity storage device element side.
• the resin components used in the heat-sealable resin layer 35 are not particularly limited, as long as they are heat-sealable, but examples include polyolefins and cyclic polyolefins.
• polystyrene resin examples include polyethylenes such as low-density polyethylene, medium-density polyethylene, high-density polyethylene, and linear low-density polyethylene; crystalline or amorphous polypropylenes such as homopolypropylene, block copolymers of polypropylene (e.g., block copolymers of propylene and ethylene), and random copolymers of polypropylene (e.g., random copolymers of propylene and ethylene); and ethylene-butene-propylene terpolymers.
• polyethylene and polypropylene are preferred.
• the cyclic polyolefin is a copolymer of an olefin and a cyclic monomer
• examples of the olefins constituting the cyclic polyolefin include ethylene, propylene, 4-methyl-1-pentene, butadiene, and isoprene.
• examples of the cyclic monomers constituting the cyclic polyolefin include cyclic alkenes such as norbornene; specifically, cyclic dienes such as cyclopentadiene, dicyclopentadiene, cyclohexadiene, and norbornadiene.
• cyclic alkenes are preferred, and norbornene is more preferred.
• Styrene is also an example of a constituting monomer.
• crystalline or amorphous polyolefins preferred are crystalline or amorphous polyolefins, cyclic polyolefins, and blended polymers thereof; more preferred are polyethylene, polypropylene, copolymers of ethylene and norbornene, and blended polymers of two or more of these.
• the heat-sealable resin layer 35 may be formed from one type of resin component alone, or may be formed from a blend polymer of two or more types of resin components. Furthermore, the heat-sealable resin layer 35 may be formed from only one layer, or may be formed from two or more layers of the same or different resin components. It is particularly preferable that the second resin layer 12b and the heat-sealable resin layer 35 are made of the same resin, as this improves the adhesion between these layers.
• the crystalline lamellar thickness of the heat-sealable resin layer 35 is preferably in the range of 5.0 to 9.0 nm.
• the crystalline lamellar thickness is measured in the same manner as the measurement of the crystalline lamellar thickness B described above, using the heat-sealable resin layer 35 as the measurement sample.
• the thickness of the heat-sealable resin layer 35 is not particularly limited, but may be about 2 to 2000 ⁇ m, preferably about 5 to 1000 ⁇ m, and more preferably about 10 to 500 ⁇ m.
• the thickness of the heat-sealable resin layer 35 may be, for example, about 100 ⁇ m or less, preferably about 85 ⁇ m or less, and more preferably about 15 to 85 ⁇ m.
• the thickness of the heat-sealable resin layer 35 is preferably about 85 ⁇ m or less, and more preferably about 15 to 45 ⁇ m.
• the thickness of the heat-sealable resin layer 35 is preferably about 20 ⁇ m or more, and more preferably about 35 to 85 ⁇ m.
• the exterior material for an electricity storage device of the present disclosure can also be in the form of a kit including the exterior material for an electricity storage device for use in an electricity storage device and the adhesive film for metal terminals of the present disclosure.
• the electricity storage device to which the present disclosure is applied includes at least an electricity storage device element having a positive electrode, a negative electrode, and an electrolyte, the exterior material for an electricity storage device that seals the electricity storage device element, and metal terminals that are electrically connected to the positive electrode and the negative electrode, respectively, and protrude outside the exterior material for an electricity storage device.
• the kit of the present disclosure is used such that the adhesive film for metal terminals of the present disclosure is interposed between the metal terminals and the exterior material for an electricity storage device.
• the electricity storage device 10 of the present disclosure comprises at least an electricity storage device element 4 having a positive electrode, a negative electrode, and an electrolyte, an exterior material for an electricity storage device 3 that seals the electricity storage device element 4, and a metal terminal 2 that is electrically connected to each of the positive electrode and the negative electrode and protrudes to the outside of the exterior material for an electricity storage device 3.
• the electricity storage device 10 of the present disclosure is characterized in that the adhesive film for a metal terminal 1 of the present disclosure is interposed between the metal terminal 2 and the exterior material for an electricity storage device 3. That is, the electricity storage device 10 of the present disclosure can be manufactured by a method including a step of interposing the adhesive film for a metal terminal 1 of the present disclosure between the metal terminal 2 and the exterior material for an electricity storage device 3.
• an electric storage device element 4 having at least a positive electrode, a negative electrode, and an electrolyte is covered with an exterior material 3 for an electric storage device by interposing an adhesive film 1 for metal terminals of the present disclosure between the metal terminals 2 and a heat-sealable resin layer 35 in a state in which the metal terminals 2 connected to the positive and negative electrodes are protruding outward, and the electric storage device element 4 is covered so that a flange portion (a region where the heat-sealable resin layers 35 contact each other, the peripheral portion 3a of the exterior material 3 for an electric storage device) of the exterior material 3 for an electric storage device is formed, and the heat-sealable resin layers 35 of the flange portion are heat-sealed to seal them, thereby providing an electric storage device 10 using the exterior material 3 for an electric storage device.
• the exterior material 3 for an electric storage device When the exterior material 3 for an electric storage device is used to house the electric storage device element 4, the exterior material 3 for an electric storage device is used so that the heat-sealable resin layer 35 of the exterior material 3 for an electric storage device is on the inside (the surface in contact with the electric storage device element 4).
• the power storage device element may be sealed by a lid in addition to the exterior material for the power storage device. That is, the exterior material for the power storage device and the lid constitute an exterior body (exterior body for the power storage device) that seals the power storage device element.
• the power storage device element may be housed inside the exterior material for the power storage device that is configured in a cylindrical shape, and the opening may be closed by the lid.
• the power storage device element connected to the lid may be housed inside the exterior material for the power storage device that is configured in a cylindrical shape so that an opening is formed, and the opening may be closed by the lid.
• the lid and the exterior material for the power storage device are preferably joined by any means. From the viewpoint of reducing the dead space between the power storage device element and the exterior material for the power storage device in order to improve the volumetric energy density of the power storage device, the exterior material for the power storage device is preferably wrapped around the power storage device element and the lid.
• the lid body can be formed, for example, from a resin molded product, a metal molded product, an exterior material for an electricity storage device, or a combination of these.
• the lid body when the lid body is expressed as a resin molded product, this does not include an embodiment in which the lid body is composed only of a film as defined by JIS K6900-1994 [Plastics terminology].
• the lid body when the lid body is a metal molded product, the lid body also functions as a metal terminal, so the metal terminal can be omitted.
• the lid body may be composed of a resin material and a conductive material.
• the exterior material for an electric storage device of the present disclosure can be suitably used for an electric storage device such as a battery (including a condenser, a capacitor, etc.).
• the exterior material for an electric storage device of the present disclosure may be used for either a primary battery or a secondary battery, but is preferably used for a secondary battery.
• the type of secondary battery to which the exterior material for an electric storage device of the present disclosure is applied is not particularly limited, and examples thereof include lithium ion batteries, lithium ion polymer batteries, all-solid batteries, semi-solid batteries, quasi-solid batteries, polymer batteries, all-resin batteries, lead-acid batteries, nickel-hydrogen batteries, nickel-cadmium batteries, nickel-iron batteries, nickel-zinc batteries, silver oxide-zinc batteries, metal-air batteries, polyvalent cation batteries, condensers, capacitors, etc.
• the exterior material for an electric storage device of the present disclosure is suitably applied to lithium ion batteries and lithium ion polymer batteries.
• Example 1 ⁇ Production of Adhesive Film> Example 1, Comparative Examples 1 and 2 Using an extruder, polypropylene (PP layer, homopolypropylene, melting peak temperature 163 ° C., thickness 80 ⁇ m) as an intermediate layer was extruded on one side as a second resin layer (resin layer A) on the exterior material side (PP layer, melting peak temperature 140 ° C.), and carbon black-containing maleic anhydride-modified polypropylene (PPa layer, melting peak temperature 140 ° C.) was extruded on the other side as a first resin layer on the metal terminal side with a thickness of 60 ⁇ m, respectively, to obtain an adhesive film (total thickness 200 ⁇ m) in which the first resin layer (PP layer, melting peak temperature 140 ° C., thickness 60 ⁇ m) / substrate (PP layer, melting peak temperature 163 ° C., thickness 80 ⁇ m) / second resin layer (resin layer A, PP layer, melting peak temperature 140 ° C., thickness 60
• the second resin layer which was the resin layer A, was manufactured under the film-forming temperature standard conditions, film-forming speed standard conditions, and cooling standard conditions to adjust the crystal lamellar thickness.
• the temperature standard conditions, film-forming rate standard conditions, and cooling conditions (chill roll temperature) of Example 1 were used as references, and the temperature, film-forming rate, and chill roll temperature were all lowered in Comparative Example 1. Meanwhile, in Comparative Example 2, the temperature and film-forming rate were increased, and the chill roll temperature was lowered.
• Example 2 Using an extruder and a T-die casting device, polypropylene (resin layer A, PP layer, melting peak temperature 140°C) was extruded as the second resin layer (resin layer A) on the exterior material side on one side of the polypropylene (PP layer, homopolypropylene, melting peak temperature 163°C, thickness 50 ⁇ m) as the intermediate layer, and carbon black-containing maleic anhydride-modified polypropylene (PPa layer, melting peak temperature 140°C) was extruded as the first resin layer on the metal terminal side on the other side, each with a thickness of 50 ⁇ m, to obtain an adhesive film (total thickness 150 ⁇ m) in which the first resin layer (PP layer, melting peak temperature 140°C, thickness 50 ⁇ m) / substrate (PP layer, melting peak temperature 163°C, thickness 50 ⁇ m) / second resin layer (resin layer A, PP layer, melting peak temperature 140°C, thickness 50 ⁇ m) were laminated in this order.
• polypropylene (PP layer, melting peak temperature 140°C) was extruded to a thickness of 40 ⁇ m as the second resin layer (resin layer A) on the exterior material side on one side of the carbon black-containing polypropylene (PP layer, homopolypropylene, melting peak temperature 160°C, thickness 60 ⁇ m) as the intermediate layer, and maleic anhydride-modified polypropylene (PPa layer, melting peak temperature 140°C) was extruded to a thickness of 50 ⁇ m as the first resin layer on the metal terminal side on the other side, and an adhesive film (total thickness 150 ⁇ m) in which the first resin layer (PP layer, melting peak temperature 140°C, thickness 50 ⁇ m) / substrate (PP layer, melting peak temperature 160°C, thickness 60 ⁇ m) / second resin layer (resin layer A, PP layer, melting peak temperature 140°C, thickness 40 ⁇ m) was obtained.
• the second resin layer which the first resin layer (PP layer, melting peak temperature 140°C, thickness 50
• a maleic anhydride-modified polypropylene (PP layer, random polypropylene, melting peak temperature 143 ° C., thickness 100 ⁇ m) was extruded on one side of the polypropylene (PP layer, random polypropylene, melting peak temperature 143 ° C., thickness 100 ⁇ m) as the intermediate layer, as the second resin layer (resin layer A) on the exterior material side, and a maleic anhydride-modified polypropylene (PPa layer, melting peak temperature 140 ° C.) was extruded on the other side as the first resin layer on the metal terminal side, each with a thickness of 25 ⁇ m, to obtain an adhesive film (total thickness 150 ⁇ m) in which the first resin layer (PP layer, melting peak temperature 140 ° C., thickness 25 ⁇ m) / substrate (PP layer, melting peak temperature 143 ° C., thickness 100 ⁇ m) / second resin layer (resin layer A
• the second resin layer which was used as resin layer A, was produced under conditions of a film-forming temperature significantly lower than the standard film-forming speed, a film-forming rate significantly slower than the standard film-forming speed, and a cooling rate faster than the standard cooling rate, thereby adjusting the crystal lamella thickness.
• a maleic anhydride-modified polypropylene (resin layer A, PPa layer, melting peak temperature 140°C) was extruded as the second resin layer (resin layer A) on the exterior material side on one side of a polypropylene (PP layer, homopolypropylene, melting peak temperature 160°C, thickness 80 ⁇ m) as an intermediate layer, and a maleic anhydride-modified polypropylene (PPa layer, melting peak temperature 140°C) was extruded as the first resin layer on the metal terminal side on the other side, each with a thickness of 35 ⁇ m, to obtain an adhesive film (total thickness 150 ⁇ m) in which the first resin layer (PP layer, melting peak temperature 140°C, thickness 35 ⁇ m)/base material (PP layer, melting peak temperature 160°C, thickness 80 ⁇ m)/second resin layer (resin layer A, PPa layer, melting peak temperature 140°C, thickness 35 ⁇ m) were laminated in this order.
• the second resin layer (total thickness 150 ⁇ m) in
• Example 5 Using an extruder, polypropylene (PP layer, homopolypropylene, melting peak temperature 163 ° C., thickness 50 ⁇ m) as an intermediate layer was extruded on one side as a second resin layer (resin layer A) on the exterior material side (PP layer, melting peak temperature 140 ° C.), and carbon black-containing maleic anhydride-modified polypropylene (PPa layer, melting peak temperature 140 ° C.) was extruded on the other side as a first resin layer on the metal terminal side with a thickness of 75 ⁇ m, respectively, to obtain an adhesive film (total thickness 200 ⁇ m) in which the first resin layer (PP layer, melting peak temperature 140 ° C., thickness 75 ⁇ m) / substrate (PP layer, melting peak temperature 163 ° C., thickness 50 ⁇ m) / second resin layer (resin layer A, PP layer, melting peak temperature 140 ° C., thickness 75 ⁇ m) was laminated in order.
• the second resin layer which was the
• the adhesive film of the metal terminal with the adhesive film and a heat-sealable resin layer (heat-sealable resin layer made of random polypropylene resin (MD 120 mm, TD 30 mm, thickness 80 ⁇ m)) of the crystalline lamellar thickness of the exterior material for a storage device described later were heat-sealed under the conditions of a temperature of 200 ° C., a pressure of 1.0 MPa, and 3 seconds to obtain a sample for measurement.
• the MD of the adhesive film and the TD of the heat-sealable resin layer of the exterior material for a storage device were made to coincide.
• the resin layer A is disposed on the outermost surface.
• Example 4 a heat-sealable resin layer having a crystalline lamellar thickness of 7.09 nm was used, in Example 4, a heat-sealable resin layer having a crystalline lamellar thickness of 5.89 nm was used, in Comparative Example 1, a heat-sealable resin layer having a crystalline lamellar thickness of 5.73 nm was used, and in Comparative Example 2, a heat-sealable resin layer having a crystalline lamellar thickness of 6.28 nm was used.
• STEM Hitachi High-Technologies Corporation S-4800 TYPE II Acceleration voltage: 30.0 kV Emission current: 10 ⁇ A ⁇ W.D: 8mm Detector: TE ⁇ Number of captured pixels: 5120 x 3840 Scan speed: 80 sec
• the heat of fusion of each measurement sample is measured in accordance with the provisions of JIS K 7122:2012.
• the measurement is performed using a differential scanning calorimeter (DSC, differential scanning calorimeter Q200 manufactured by TA Instruments).
• DSC differential scanning calorimeter
• the measurement sample is held at -50°C for 15 minutes, then heated from -50°C to 210°C at a heating rate of 10°C/min, the first heat of fusion ⁇ H (J/g) is measured, and then held at 210°C for 10 minutes. Next, the temperature is lowered from 210°C to -50°C at a heating rate of 10°C/min and held for 15 minutes.
• the temperature is raised from -50°C to 210°C at a heating rate of 10°C/min to measure the second heat of fusion ⁇ H (J/g).
• the flow rate of nitrogen gas is 50 ml/min.
• the value of the heat of fusion ⁇ H (J/g) measured in the first measurement by the above procedure is adopted.
• the heat of fusion is defined as the melting peak area surrounded by the baseline (a straight line connecting 80°C to 170°C on the DSC curve) and the peak in the DSC curve. Meanwhile, the heat of fusion of crystals in a temperature range below X°C is calculated from the area of the melting peak area in the temperature range below X°C when calculating the total heat of fusion of crystals.
• a two-liquid urethane adhesive a polyol compound and an aromatic isocyanate compound
• the adhesive layer and a polyethylene terephthalate film were laminated on the nylon film to prepare a base layer.
• a two-liquid urethane adhesive (a polyol compound and an aromatic isocyanate compound) was applied on one surface of a barrier layer consisting of an aluminum alloy foil, and an adhesive layer (thickness 3 ⁇ m) was formed on the aluminum alloy foil.
• the adhesive layer and the substrate layer with the nylon film side as the adhesive surface were laminated on the aluminum alloy foil, and then aging treatment was performed to produce a substrate layer/adhesive layer/barrier layer laminate.
• an adhesive layer (40 ⁇ m thick, arranged on the metal layer side) made of maleic anhydride-modified polypropylene resin and a heat-sealable resin layer (80 ⁇ m thick, innermost layer) made of random polypropylene resin were co-extruded on the barrier layer of the laminate to laminate the adhesive layer/heat-sealable resin layer on the barrier layer, thereby obtaining an exterior material for a power storage device in which the substrate layer, adhesive layer, barrier layer, adhesive layer, and heat-sealable resin layer were laminated in this order.
• Example 4 a heat-sealable resin layer having a crystalline lamella thickness of 7.09 nm was used, in Example 4, a heat-sealable resin layer having a crystalline lamella thickness of 5.89 nm was used, in Comparative Example 1, a heat-sealable resin layer having a crystalline lamella thickness of 5.73 nm was used, and in Comparative Example 2, a heat-sealable resin layer having a crystalline lamella thickness of 6.28 nm was used.
• each adhesive film 1 obtained in the examples and comparative examples was cut to a length of 45 mm and a width of 20 mm.
• a metal terminal was sandwiched between two adhesive films to obtain an adhesive film/metal terminal/adhesive film laminate.
• the MD and TD of the metal terminal were aligned with the length direction and width direction of the adhesive film, respectively, and the metal terminal and adhesive film were laminated so that their centers were aligned (see Figure 9(a)).
• the first resin layer of the adhesive film for the metal terminal was arranged on the metal terminal side.
• the laminate was sandwiched between two polytetrafluoroethylene films (PTFE films, thickness 100 ⁇ m), and heated at a temperature of 200 ° C., a surface pressure of 0.25 MPa, and a time of 16 seconds (once), to heat-seal the first resin layer of the adhesive film to the metal terminal, thereby producing a metal terminal with an adhesive film (see FIG. 9 (b)).
• PTFE films polytetrafluoroethylene films
• the metal terminal was sandwiched between the adhesive films, so that the periphery of the metal terminal was covered with the adhesive film, and a portion in which the two adhesive films were heat-sealed to each other was formed.
• the exterior material was cut to a size of TD 60 mm and MD 200 mm, and as shown in the schematic diagram of FIG. 10, the exterior material was placed facing each other with the heat-sealable resin layer of the exterior material facing inside, and the obtained laminate was sandwiched between the opposing heat-sealable resin layers (see FIG. 10 (a)). At this time, the exterior material was laminated so that the MD and TD of the exterior material were aligned with the width direction and length direction of the laminate, respectively.
• a heat seal tester was used to perform heat sealing (see the shaded area S in FIG. 10(b)) under conditions of a width of 7 mm (7 mm in the y-axis direction in FIG. 10(b)), 200°C, surface pressure of 1.0 MPa, and 3.0 seconds, and the laminate was naturally cooled to 25°C to obtain a laminate in which the exterior material and the adhesive film were heat-sealed (see FIG. 10(b)).
• the central part in the short side direction of the obtained laminate was cut to a width of 15 mm (see the two-dot dashed line in FIG. 10(b) for the cutting position).
• the adhesive film and the heat-sealable resin layer of the exterior material were peeled off using a Tensilon universal material testing machine (RTG-1210 manufactured by A&D Co., Ltd.).
• the maximum strength at the time of peeling was taken as the peel strength (N/15 mm) against the exterior material.
• the peel speed was 20 mm/min
• the peel angle was 180°
• the chuck distance was 30 mm
• the average value was calculated from three measurements.
• the evaluation criteria for adhesive strength in a 25° C. environment and a 60° C. environment are as follows. (Evaluation criteria for adhesive strength in a 25°C environment) A: Peel strength is 100 N/15 mm or more B: Peel strength is less than 100 N/15 mm (evaluation criteria for adhesive strength in a 60° C. environment) A: Peel strength is 80N/15mm or more B: Peel strength is less than 80N/15mm
• An adhesive film for a metal terminal which is interposed between a metal terminal electrically connected to an electrode of an electricity storage device element and an exterior material for an electricity storage device that encapsulates the electricity storage device element, the electrical storage device exterior material includes a thermally adhesive resin layer disposed on an outermost surface on the electrical storage device element side,
• the adhesive film for metal terminal has one surface composed of a resin layer A,
• the adhesive film for metal terminal and the metal terminal are heat-sealed under conditions of a temperature of 200°C, a pressure of 0.25 MPa, and a time of 16 seconds to obtain a metal terminal with an adhesive film for metal terminal, in which the resin layer A is positioned on the surface; and when the adhesive film for metal terminal of the metal terminal with the adhesive film for metal terminal and the heat-sealable resin layer having a crystalline lamellar thickness of 5.0 to 9.0 nm are heat-sealed under conditions of a temperature of 200°C, a pressure
• Item 2. The adhesive film for metal terminal according to item 1, which contains a polyolefin skeleton.
• Item 3. The adhesive film for a metal terminal according to item 1 or 2, which has a multilayer structure.
• Item 4. The adhesive film for metal terminal according to any one of Items 1 to 3, wherein the adhesive film for metal terminal is composed of a laminate including, in this order, a first resin layer disposed on the metal terminal side, an intermediate layer, and a second resin layer disposed on the exterior material side for the electric storage device.
• Item 5. The adhesive film for a metal terminal according to Item 4, wherein the second resin layer disposed on the exterior material side for an electricity storage device is the resin layer A.
• the adhesive film for metal terminal according to any one of items 1 to 5, having a thickness of 100 ⁇ m or more.
• Item 7 A method for producing an adhesive film for a metal terminal, which is interposed between a metal terminal electrically connected to an electrode of an electricity storage device element and an exterior material for an electricity storage device that encapsulates the electricity storage device element, comprising: the electrical storage device exterior material includes a thermally adhesive resin layer disposed on an outermost surface on the electrical storage device element side, The adhesive film for metal terminal has one surface composed of a resin layer A, The adhesive film for metal terminal and the metal terminal are heat-sealed under conditions of a temperature of 200°C, a pressure of 0.25 MPa, and a time of 16 seconds to obtain a metal terminal with an adhesive film for metal terminal, in which the resin layer A is positioned on the surface; and when the adhesive film for metal terminal of the metal terminal with the adhesive film for metal terminal and the heat-sealable resin layer having a crystalline lamellar thickness of 5.0 to 9.0 nm
• a metal terminal with an adhesive film for a metal terminal comprising a metal terminal and an adhesive film for a metal terminal attached thereto, The metal terminal is used so as to be electrically connected to an electrode of an electricity storage device element,
• the adhesive film for a metal terminal is used by being interposed between the metal terminal and an exterior material for an electricity storage device that encapsulates the electricity storage device element, the electrical storage device exterior material includes a thermally adhesive resin layer disposed on an outermost surface on the electrical storage device element side,
• a metal terminal with an adhesive film for a metal terminal wherein when a resin layer A constituting the surface of the adhesive film for a metal terminal of the metal terminal with the adhesive film for a metal terminal and the heat-fusible resin layer having a crystalline lamellar thickness of 5.0 to 9.0 nm are heat-fused under conditions of a temperature of 200°C, a pressure of 1.0 MPa, and a time of 3 seconds, at the heat-fused portion between the adhesive film for a metal terminal and the heat-fusible
• An electricity storage device including at least an electricity storage device element having a positive electrode, a negative electrode, and an electrolyte, an exterior material for an electricity storage device that seals the electricity storage device element, and metal terminals that are electrically connected to the positive electrode and the negative electrode, respectively, and protrude to the outside of the exterior material for an electricity storage device
• the electrical storage device packaging material is composed of a laminate having at least a base layer, a barrier layer, and a thermally adhesive resin layer in this order, an adhesive film for a metal terminal is interposed between the metal terminal and the heat-sealable resin layer of the exterior material for an electricity storage device,
• the crystalline lamellar thickness B of the heat-fusible resin layer is 5.0 to 9.0 nm
• An electricity storage device wherein the difference between a crystalline lamellar thickness A measured for a resin layer A constituting one surface of the adhesive film for metal terminals and a crystalline lamellar thickness B of the heat-sealable resin layer is 0.3 nm or
• the electricity storage device includes at least an electricity storage device element having a positive electrode, a negative electrode, and an electrolyte, the electricity storage device exterior material sealing the electricity storage device element, and the metal terminals electrically connected to the positive electrode and the negative electrode, respectively, and protruding to the outside of the electricity storage device exterior material, and an adhesive film for metal terminals is interposed between the metal terminals and the electricity storage device exterior material,
• the adhesive film for metal terminal is the adhesive film for metal terminal according to any one of items 1 to 6,
• the electrical storage device packaging material is composed of a laminate including at least a base layer, a barrier layer, and a heat-sealable resin layer in this order.
• a kit comprising an exterior material for an electricity storage device for use in an electricity storage device and the adhesive film for a metal terminal according to any one of Items 1 to 6,
• the electricity storage device includes at least an electricity storage device element having a positive electrode, a negative electrode, and an electrolyte, the electricity storage device exterior material sealing the electricity storage device element, and the metal terminals electrically connected to the positive electrode and the negative electrode, respectively, and protruding to the outside of the electricity storage device exterior material,
• the kit is used such that, when in use, the adhesive film for a metal terminal is interposed between the metal terminal and the exterior material for an electricity storage device.
• a kit comprising an exterior material for an electricity storage device for use in an electricity storage device and the metal terminal with an adhesive film for a metal terminal according to Item 8
• the electricity storage device includes at least an electricity storage device element having a positive electrode, a negative electrode, and an electrolyte, the electricity storage device exterior material sealing the electricity storage device element, and a metal terminal with the adhesive film for metal terminal electrically connected to each of the positive electrode and the negative electrode and protruding outside the electricity storage device exterior material
• the electrical storage device packaging material is composed of a laminate having at least a base layer, a barrier layer, and a thermally adhesive resin layer in this order,
• the kit is used such that, when used, the metal terminal with the adhesive film for a metal terminal is interposed between the heat-sealable resin layers of the exterior material for an electricity storage device.

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