WO2021256093A1 - Insulating sheet and power supply device comprising same - Google Patents

Insulating sheet and power supply device comprising same Download PDF

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Publication number
WO2021256093A1
WO2021256093A1 PCT/JP2021/016675 JP2021016675W WO2021256093A1 WO 2021256093 A1 WO2021256093 A1 WO 2021256093A1 JP 2021016675 W JP2021016675 W JP 2021016675W WO 2021256093 A1 WO2021256093 A1 WO 2021256093A1
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WO
WIPO (PCT)
Prior art keywords
heat insulating
insulating sheet
intermediate layer
surface layer
layer
Prior art date
Application number
PCT/JP2021/016675
Other languages
French (fr)
Japanese (ja)
Inventor
裕也 西尾
洋史 千葉
Original Assignee
阿波製紙株式会社
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Application filed by 阿波製紙株式会社 filed Critical 阿波製紙株式会社
Priority to JP2022532357A priority Critical patent/JPWO2021256093A1/ja
Publication of WO2021256093A1 publication Critical patent/WO2021256093A1/en

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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B3/00—Layered products comprising a layer with external or internal discontinuities or unevennesses, or a layer of non-planar form; Layered products having particular features of form
    • B32B3/26—Layered products comprising a layer with external or internal discontinuities or unevennesses, or a layer of non-planar form; Layered products having particular features of form characterised by a particular shape of the outline of the cross-section of a continuous layer; characterised by a layer with cavities or internal voids ; characterised by an apertured layer
    • B32B3/266—Layered products comprising a layer with external or internal discontinuities or unevennesses, or a layer of non-planar form; Layered products having particular features of form characterised by a particular shape of the outline of the cross-section of a continuous layer; characterised by a layer with cavities or internal voids ; characterised by an apertured layer characterised by an apertured layer, the apertures going through the whole thickness of the layer, e.g. expanded metal, perforated layer, slit layer regular cells B32B3/12
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B7/00—Layered products characterised by the relation between layers; Layered products characterised by the relative orientation of features between layers, or by the relative values of a measurable parameter between layers, i.e. products comprising layers having different physical, chemical or physicochemical properties; Layered products characterised by the interconnection of layers
    • B32B7/02—Physical, chemical or physicochemical properties
    • B32B7/027—Thermal properties
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16L—PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
    • F16L59/00—Thermal insulation in general
    • F16L59/02—Shape or form of insulating materials, with or without coverings integral with the insulating materials
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/60—Heating or cooling; Temperature control
    • H01M10/61—Types of temperature control
    • H01M10/613—Cooling or keeping cold
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/60—Heating or cooling; Temperature control
    • H01M10/65—Means for temperature control structurally associated with the cells
    • H01M10/658—Means for temperature control structurally associated with the cells by thermal insulation or shielding
    • 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
    • H01M50/20—Mountings; Secondary casings or frames; Racks, modules or packs; Suspension devices; Shock absorbers; Transport or carrying devices; Holders
    • 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 invention relates to a heat insulating sheet and a power supply device including the heat insulating sheet.
  • Sheet materials with heat insulating properties are used in various applications such as spacers for heat insulation and insulation of secondary battery cells, explosion-proof sheets, and sheet materials for covering members with different temperatures such as refrigerators.
  • a spacer for heat insulation of a secondary battery cell will be described.
  • a power supply device in which multiple secondary battery cells are stacked is used as a power source for driving electric vehicles such as electric vehicles, hybrid vehicles, electric buses, and trains, as a backup power source for factories and base stations, and as a storage battery for home use. (For example, Patent Documents 1 and 2).
  • Patent Documents 1 and 2 In recent years, there has been a demand for weight reduction and high capacity of power supply devices, and high capacity types such as lithium ion secondary batteries are used for secondary battery cells.
  • the thermal conductivity is low. Therefore, as shown in the schematic cross-sectional view of FIG. 4, even if hot spot HS occurs in any of the secondary battery cells 1. This high heat cannot be thermally conducted and dissipated by the heat insulating sheet 10X, and as a result, the generation of high temperature cannot be suppressed and thermal runaway occurs. However, if the thermal conductivity is increased, the heat insulating performance cannot be exhibited and the high temperature propagates to the adjacent secondary battery cells, and the occurrence of burning cannot be suppressed. As described above, the suppression of the generation of hot spots and the prevention of burning are contradictory characteristics, and it is difficult to achieve both.
  • Patent Document 2 a configuration has been proposed in which a composite sheet including a heat insulating layer and heat conductive sheets arranged on both sides thereof is formed between the secondary battery cells. According to this, it is said that the heat dissipation from the battery cell to the housing is excellent and the heat insulation between adjacent battery cells is excellent.
  • PET polyethylene terephthalate
  • silica xerogel a PET non-woven fabric impregnated with silica xerogel
  • the present invention has been made in view of such a background, and one of the purposes thereof is to provide a heat insulating sheet having reduced processing costs while maintaining heat insulating performance and a power supply device provided with the heat insulating sheet.
  • the heat insulating sheet includes an intermediate layer and a surface layer laminated on the surface of the intermediate layer, and the thermal conductivity of the surface layer in the thickness direction is 0.
  • the thermal conductivity of the intermediate layer in the thickness direction is 1.00 W / m ⁇ K or more, and the pore diameter of the surface layer can be 50 ⁇ m or less.
  • an intermediate layer and a surface layer laminated on the surface of the intermediate layer are provided, and the surface layer is provided with the intermediate layer.
  • the thermal conductivity in the thickness direction is 0.50 W / m ⁇ K or less
  • the thermal conductivity in the thickness direction of the intermediate layer is 1.00 W / m ⁇ K or more
  • the surface layer is The air permeation resistance can be set to 3 to 5000 sec / 100 mL with a Garley standard type densometer conforming to the JIS P 8117 (2009) test.
  • the surface layer can be laminated on both sides of the intermediate layer.
  • the thermal conductivity of the intermediate layer in the plane direction may be 1000 W / m ⁇ K or less. can.
  • the thermal conductivity of the intermediate layer in the thickness direction is set to 3.00 W / m ⁇ K or less. can do.
  • the thermal conductivity in the plane direction of the intermediate layer is five times the thermal conductivity in the thickness direction. The above can be done. With the above configuration, even if a hot spot is partially generated in the surface direction, heat is conducted in the surface direction to suppress the generation of hot spots, and thus the generation of burning can be suppressed.
  • the intermediate layer can be composed of a papermaking sheet.
  • the intermediate layer can contain fibers or a heat conductive filler.
  • the intermediate layer can contain any of graphite, boron nitride, and aluminum.
  • the ash on the back surface when heated for 10 minutes according to the JIS L 1091 A-1 method (1999) test can be 500 mm 2 or less.
  • the volume resistivity of the surface layer can be set to 10 10 or more in addition to any of the above configurations. With the above configuration, the insulation after combustion can be maintained.
  • the surface layer can contain at least one of fibers, a filler, and a binder. With the above configuration, it is possible to prevent powder from falling from the surface layer.
  • the adhesive layer for adhering the intermediate layer and the surface layer is an acrylic adhesive or a vinyl chloride adhesive. , Vinyl acetate-based adhesive, or at least one of hot melt.
  • the thickness can be 0.2 mm to 6.0 mm in addition to any of the above configurations.
  • the compression rate when the surface layer is compressed at 100 kPa can be set to 10% or more.
  • the heat resistant temperature can be set to 300 to 600 ° C. in addition to any of the above configurations.
  • a heat insulating sheet used for a power supply device in which a plurality of secondary battery cells are laminated the heat insulating sheet and the intermediate layer.
  • a surface layer laminated on the surface of the intermediate layer is provided, and the thermal conductivity of the surface layer in the thickness direction is 0.50 W / m ⁇ K or less, and the heat conductivity of the surface layer is 0.50 W / m ⁇ K or less in the thickness direction.
  • the thermal conductivity of the surface layer is 1.00 W / m ⁇ K or more, and the pore diameter of the surface layer can be 50 ⁇ m or less.
  • any one of the above heat insulating sheets and a plurality of secondary battery cells laminated with the heat insulating sheet interposed therebetween can be provided.
  • FIG. 3 is a vertical sectional view taken along line II-II of the power supply device of FIG.
  • FIG. 3 is an enlarged schematic cross-sectional view showing a heat insulating sheet according to the first embodiment. It is a schematic cross-sectional view which shows the state which the hot spot occurred in the structure which insulated between the secondary battery cells with the conventional heat insulating sheet. It is a schematic cross-sectional view which shows the state which hot spot occurred in the structure which insulated between pouch type secondary battery cells by the heat insulating sheet which concerns on Embodiment 1.
  • FIG. 6A is a side view showing the mounting position of the ceramic heater and the thermocouple in the front and back temperature evaluation test
  • FIG. 6B is a plan view showing the mounting position of the thermocouple on the upper surface of the heater
  • FIG. 6C shows the mounting position of the thermocouple on the back side of the sample. It is a bottom view which shows.
  • FIG. 7A is a photograph of the sample of Example 1 taken from the heater surface
  • FIG. 7B is a photograph taken from the back surface side with a thermography camera
  • FIG. 8A is a photograph of the sample of Example 2 taken from the heater surface
  • FIG. 8B is a photograph taken from the back surface side with a thermography camera.
  • FIG. 9A is a photograph of the heater surface of the sample of Example 3, and FIG.
  • FIG. 9B is a photograph of the back surface side of the sample, respectively, taken by a thermography camera.
  • FIG. 10A is a photograph of the heater surface of the sample of Example 4, and FIG. 10B is a photograph of the back surface side of the sample, respectively, taken by a thermography camera.
  • FIG. 11A is a photograph of the heater surface of the sample of Comparative Example 1 and FIG. 11B is a photograph of the back surface side of the sample taken by a thermography camera. It is a schematic diagram which shows the combustion test of a sample.
  • FIG. 13A is a photograph showing how the incinerated area is measured by the image processing software
  • FIG. 13B is a photograph showing how the carbonized area is measured.
  • FIG. 13A is a photograph showing how the incinerated area is measured by the image processing software
  • FIG. 13B is a photograph showing how the carbonized area is measured.
  • FIG. 14A is a photograph of the combustion surface of the sample of Example 1 after the combustion test
  • FIG. 14B is a photograph of the back surface of the sample.
  • FIG. 15A is a photograph of the combustion surface of the sample of Example 2 after the combustion test
  • FIG. 15B is a photograph of the back surface of the sample.
  • FIG. 16A is a photograph of the combustion surface of the sample of Example 3 after the combustion test
  • FIG. 16B is a photograph of the back surface of the sample.
  • FIG. 17A is a photograph of the combustion surface of the sample of Example 4 after the combustion test
  • FIG. 17B is a photograph of the back surface of the sample.
  • FIG. 18A is a photograph of the combustion surface of the sample of Comparative Example 1 after the combustion test
  • FIG. 18B is a photograph of the back surface of the sample. It is a schematic cross-sectional view which shows the conventional composite sheet.
  • each element constituting the present invention may be configured such that a plurality of elements are composed of the same member and the plurality of elements are combined with one member, or conversely, the function of one member is performed by the plurality of members. It can also be shared and realized.
  • the heat insulating sheet according to the embodiment of the present invention can be appropriately used for applications requiring heat insulating properties.
  • it can be used as a heat insulating material for insulating refrigerators, freezers, etc., a heat insulating sheet for building materials, and the like.
  • a heat insulating sheet is used as a spacer interposed between adjacent secondary battery cells in a power supply device in which a large number of secondary battery cells are stacked and connected in series or in parallel will be described.
  • a power supply device is used as a power source for driving electric vehicles such as electric vehicles, hybrid vehicles, electric buses, trains, and electric carts, as a backup power source for factories and base stations, and as a storage battery for home use. ..
  • a power supply device using the heat insulating sheet according to the first embodiment is shown in a perspective view of FIG. 1 and a vertical sectional view of FIG.
  • the power supply device 100 shown in these figures includes a plurality of secondary battery cells 1 and a heat insulating sheet 10 interposed between the secondary battery cells 1. In this way, the secondary battery cell 1 and the heat insulating sheet 10 are alternately laminated to form a battery laminate. Further, a side plate 2 is arranged on the side surface of the battery laminate as needed. The side plate 2 is thermally coupled to the side surface of the secondary battery cell 1 and functions as a heat radiating plate that dissipates heat by heat conduction. (Insulation sheet 10)
  • a heat insulating sheet 10 is interposed between the adjacent secondary battery cells 1.
  • the heat insulating sheet 10 is called a spacer, a separator, or the like, and is a member for insulating between adjacent secondary battery cells 1 to prevent or suppress burning.
  • the heat insulating sheet 10 can be made to function as a heat radiating member by thermally coupling the upper end, the lower end, the side surface and the like with a heat radiating plate or the like.
  • heat dissipation fins can be arranged above and below the battery laminate, and the upper and lower ends of the heat insulating sheet can be thermally coupled to the heat dissipation fins, respectively. (Secondary battery cell 1)
  • a lithium ion secondary battery can be preferably used as the secondary battery cell 1.
  • the exterior material of the secondary battery cell 1 is made of a conductive member.
  • insulation is required in addition to heat insulation.
  • the heat insulating sheet 10 according to the present embodiment is suitably used for a power supply device using a secondary battery cell using such a conductive outer can by forming the surface layer 12 with a sheet having insulating properties. can.
  • the present invention can also be used for a secondary battery cell having an insulating outer material, for example, a pouch type or a laminated type having a plate-shaped outer shape. (Insulation sheet 10)
  • FIG. 1 An enlarged cross-sectional view of the heat insulating sheet 10 is shown in FIG.
  • the heat insulating sheet 10 shown in this figure is composed of an intermediate layer 11 and a surface layer 12 laminated on both sides so as to sandwich the intermediate layer 11.
  • the thermal conductivity is different between the intermediate layer 11 and the surface layer 12.
  • the thermal conductivity in the thickness direction of the surface layer 12 is 0.50 W / m ⁇ K or less
  • the thermal conductivity in the thickness direction of the intermediate layer 11 is 1.00 W / m ⁇ K or more. ..
  • the insulating sheet has a multi-layered structure in which each surface layer 12 is a heat insulating layer having suppressed thermal conductivity, and the intermediate layer 11 interposed between them is a heat radiating layer having improved thermal conductivity. Even if the layer 12 is thin, the heat insulating sheet 10 having excellent heat insulating performance can be realized.
  • the thermal conductivity of the intermediate layer 11 in the plane direction is 5 times or more in the thickness direction. As a result, it is possible to prevent burning while effectively eliminating the generation of hot spots while demonstrating the heat insulating performance of the heat insulating sheet 10 combined with the surface layer 12 having high heat insulating performance.
  • the conventional heat insulating sheet was made of a material with high heat insulating performance, in other words, low thermal conductivity, from the viewpoint of preventing burning.
  • this high heat is thermally conducted by the heat insulating sheet 10X to dissipate heat.
  • the hot spot HS which has no heat escape, becomes hotter and hot, and there is a possibility that it will eventually burn and run away from heat.
  • the surface layer 12 is opposed to the secondary battery cell 1 as a heat insulating layer having suppressed thermal conductivity.
  • the heat insulating sheet 10 interposed between the adjacent secondary battery cells 1 can insulate the left and right secondary battery cells with high heat insulating properties.
  • the surface layer 12 as an insulating layer, it is possible to avoid an unintended short circuit between the secondary battery cells.
  • a secondary battery cell whose outer can is made of metal it is possible to improve the insulation between the secondary battery cells and contribute to the improvement of safety and reliability.
  • the surface layer facing the secondary battery cell. 12 (on the right side in FIG. 5) exhibits heat insulating properties, but the heat that has reached the intermediate layer 11 is positively conducted in the plane direction, so that the heat is propagated and diffused over the entire surface of the surface layer 12.
  • the expansion of the hot spot can be suppressed by removing heat from the place where the high temperature is generated.
  • the thermal conductivity of the intermediate layer 11 in the surface direction is promoted, the heat conduction to the back surface side is suppressed, and the heat conduction to the back surface side is suppressed.
  • the end face of the heat insulating sheet 10 is thermally coupled to the side plate 2 or thermally coupled to the heat radiating member to further improve the heat radiating property, and heat is absorbed from the secondary battery cell to cause thermal runaway. Can be suppressed.
  • the heat insulating effect of the surface layer 12 on the back surface side can prevent or suppress the propagation of high heat to other secondary battery cells, and can reduce the risk of burning.
  • the heat insulating sheet 10 has a multi-layer structure, and a heat diffusion function is added to the intermediate layer 11 to suppress hot spot HS, while a heat insulating function is added to the surface layer 12 to the other secondary battery cells. By preventing burning, it enhances safety by achieving both the contradictory functions of heat dissipation performance and heat insulation performance, which were difficult to achieve in the past. (Surface layer 12)
  • the surface layer 12 has a thermal conductivity of 0.50 W / m ⁇ K or less in the thickness direction, more preferably 0.01 W / m ⁇ K to 0.30 W / m ⁇ K, still more preferably 0.02 W / m ⁇ K. It is set to K to 0.20 W / m ⁇ K.
  • Such a surface layer 12 preferably contains any of fibers, fillers, and binders in order to exhibit sufficient heat insulating performance.
  • the pore diameter of the surface layer 12 is preferably 50 ⁇ m or less, more preferably 30 ⁇ m or less, and even more preferably 20 ⁇ m or less. As a result, it is possible to suppress the powder falling of the heat insulating sheet and eliminate the need for a treatment for preventing the powder falling such as sealing the surface layer.
  • the air permeability resistance of the surface layer 12 is preferably 3 to 5000 sec / 100 ml, more preferably 5 to 1000 sec / 100 ml, using a Garley standard densometer conforming to the JIS P 8117 (2009) test. If the air permeation resistance is smaller than this range, when the fiber or powder falls off from the intermediate layer described later, its scattering cannot be prevented and a short circuit may occur. Further, when the air permeation resistance is larger than this range, the adhesive strength with the adhesive layer described later tends to decrease.
  • the smoothness of the surface layer 12 is a smoothness tester based on JIS P 8119 (1998), and the time until the pressure in the vacuum vessel changes from 50.7 kPa to 29.3 kPa is 15 to 150 sec. Is preferable.
  • the surface layer 12 has a compression rate of 10% or more when compressed at 100 kPa.
  • the surface layer 12 of the heat insulating sheet 10 includes a fiber base material, a filler, and a binder.
  • a fiber base material Preferably, natural pulp and inorganic fibers can be used as the fiber base material, silicate minerals can be used as the filler, and rubber compositions can be used as the binder.
  • the surface layer 12 according to the first embodiment contains hemp pulp and microglass as a fiber base material, talc and sepiolite as a filler, and NBR as a binder.
  • the fiber base material also called base fiber
  • inorganic fibers such as glass fibers, carbon fibers and ceramic fibers, or organic fibers such as aromatic polyamide fibers and polyethylene fibers
  • natural pulp of organic fiber is used as the fiber base material.
  • Hemp pulp can be preferably used as natural pulp.
  • the blending ratio of hemp pulp is, for example, 5% by weight to 20% by weight, preferably 10% by weight.
  • Inorganic fibers may also be included as the fiber base material.
  • the blending ratio of the inorganic fibers is 5% by weight to 20% by weight, preferably 8% by weight to 15% by weight.
  • 12% by weight of microglass is added as an inorganic fiber.
  • Inorganic filler can be used as the filler.
  • Inorganic fillers include silicate minerals such as sepiolite, talc, kaolin, mica, and sericite, magnesium carbonate, calcium carbonate, hard clay, calcined clay, barium sulfate, calcium silicate, wollastonite, sodium bicarbonate, and white carbon.
  • -Synthetic silica such as molten silica, natural silica such as silicate soil, aluminum hydroxide, magnesium hydroxide, glass beads and the like can be mentioned, and these may be used alone or in combination of two or more.
  • the addition of these inorganic fillers has the effects of maintaining the shape and improving the heat insulating property in a high temperature atmosphere.
  • talc having high flexibility was used.
  • the blending amount of the filler is preferably 5% by weight to 65% by weight in the heat insulating sheet.
  • magnesium silicate is used as a filler, and 58% by weight of talc and 14% by weight of sepiolite are added.
  • the binder includes vinyl chloride resin, vinylidene chloride resin, acrylic acid resin, urethane resin, vinyl acetate resin, polyethylene resin, polystyrene resin, acrylobutadiene styrene resin, acrylonitrile styrene resin, fluororesin, silicone resin, epoxy resin, and phenol.
  • acrylic nitrile butadiene rubber hydride acrylic nitrile butadiene rubber, acrylic rubber, acrylic nitrile rubber, ethylene propylene rubber, styrene butadiene rubber, chloroplane rubber, butadiene rubber, butyl rubber, fluororubber, silicone rubber , Fluorosilicone rubber, chlorosulphonized rubber, ethylene vinegar rubber, polyethylene chloride, butyl chloride rubber, epichlorohydrin rubber, nitrile isoprene rubber, natural rubber, isoprene rubber and the like can be used.
  • acrylic nitrile butadiene rubber NBR
  • NBR acrylic nitrile butadiene rubber
  • rubbers can be used alone or in combination of two or more. Further, for the purpose of higher water resistance and oil resistance, a sizing agent such as an alkyl ketene dimer and a fluorine-based or silicone-based water repellent can be used in combination.
  • a rubber composition is used as the binder, the amount of rubber to be blended is preferably 5.0 to 40% by weight in the heat insulating sheet. Here, 6.0% by weight of NBR Nipol 1562 is added.
  • chemicals such as paper strength agents, fixing agents, and antifoaming agents are added.
  • 0.5% by weight of WS4030 was added as a paper strength agent
  • 0.3% by weight of cogham 15H was added as a paper strength agent
  • 1.9% by weight of a sulfate band was added as a fixing agent
  • an appropriate amount of KM-70 was added as an antifoaming agent. ing.
  • the surface layer 12 has a thickness of 1 mm to 5.5 mm, preferably 0.15 mm to 2 mm, and more preferably 0.2 mm to 1 mm.
  • the surface layer 12 may be composed of a plurality of layers of inorganic fiber layers such as a layered glass fiber layer and a ceramic fiber layer.
  • the inorganic fiber a fiber having a fiber length of 13 mm or more can be preferably used from the viewpoint of compressive stability. It is more preferably 40 mm or more, and even more preferably uncut long fiber. (Middle layer 11)
  • the intermediate layer 11 has a thermal conductivity of 1.00 W / m ⁇ K or more in the thickness direction, preferably 2.00 W / m ⁇ K to 20.00 W / m ⁇ K, and more preferably 2.50 W / m ⁇ K. It is set to ⁇ 15.00 W / m ⁇ K.
  • the thermal conductivity of the intermediate layer 11 in the thickness direction may be 3.00 W / m ⁇ K or less.
  • the thermal conductivity of the intermediate layer 11 in the plane direction is preferably 1000 W / m ⁇ K or less.
  • such an intermediate layer 11 contains an organic fiber or a heat conductive filler in order to exhibit sufficient heat conductivity.
  • the organic fiber any one or more of para-aramid fiber, para-aramid pulp, meta-aramid pulp, polyphenylene sulfide fiber, PET fiber, flame-retardant PET fiber, and flame-retardant rayon fiber can be used.
  • the heat conductive filler magnesium oxide, aluminum oxide, boron nitride, aluminum nitride, aluminum, copper, graphite, carbon nanotubes and the like can be used.
  • the intermediate layer 11 may contain inorganic fibers.
  • the inorganic fiber carbon fiber, glass fiber, ceramic fiber and the like can be used.
  • the intermediate sheet composed of the papermaking sheet may be pressure-processed by a thermal calender roll or the like. As a result, the inside can be densified and the thermal conductivity can be increased.
  • a film-like metal such as iron, aluminum, copper, silver, and gold can be used as the intermediate layer 11.
  • the thickness of the intermediate layer 11 is 0.02 mm to 0.5 mm, preferably 0.03 mm to 0.4 mm, and more preferably 0.03 mm to 0.3 mm.
  • the air permeability resistance of the intermediate layer 11 is 3000 sec / ml or more with a Garley standard type densometer conforming to the JIS P 8117 (2009) test.
  • the intermediate layer 11 having heat diffusivity with less powder falling is realized, and there is an advantage that the production can be easily and inexpensively performed without the need for sealing the layer having heat diffusivity.
  • the intermediate layer 11 and the surface layer 12 are adhered with an adhesive.
  • An adhesive layer obtained by curing the adhesive is interposed between the intermediate layer 11 and the surface layer 12.
  • the adhesive material is preferably a material having excellent heat resistance.
  • an acrylic adhesive, a vinyl chloride adhesive, a vinyl acetate adhesive, a hot melt, or the like can be used.
  • the form of the adhesive can be liquid, slurry, or a heat-sealed sheet obtained by molding a hot melt adhesive into a non-woven fabric or a net.
  • the overall thickness of the heat insulating sheet 10 is 0.2 mm to 6.0 mm, preferably 0.2 mm to 4.0 mm, and more preferably 0.3 mm to 2.0 mm.
  • the heat insulating sheet 10 has flexibility and flexibility. As a result, when the secondary battery cell 1 expands as shown in the cross-sectional view of FIG. 5, it follows the deformation of the secondary battery cell 1 and maintains a close contact state, and is thermally conductive due to the formation of voids. Can be avoided.
  • many of the conventional heat insulating sheets are hard and have low followability to deformation. Therefore, voids are formed on the contact surface and the heat insulating effect of the air layer may reduce the thermal conductivity.
  • a hard heat insulating sheet is rather convenient because the heat insulating performance is further improved by the air layer.
  • the surface layer 12 should be a heat insulating sheet 10 having flexibility and flexibility rather than such a hard material in order to exhibit heat dissipation performance. Therefore, it is possible to maintain a high thermal conductivity and exhibit heat dissipation performance.
  • the heat insulating sheet 10 flexibility and flexibility, it becomes possible to wind it on a winding material such as a roll material, it becomes possible to store and transport it in a roll shape, and the handling property is improved.
  • a winding material such as a roll material
  • the handling property is improved.
  • in order to exhibit flexibility for example, when a cylinder having an outer diameter of 110 mm is applied to one side of the heat insulating sheet 10 and bent by 90 °, wrinkles or cracks can be prevented.
  • the heat insulating sheet 10 has heat resistance and flame retardancy. Even if the secondary battery cell 1 becomes hot, the heat insulating performance can be maintained by using a material that is not easily deformed or melted.
  • the heat resistant temperature of the heat insulating sheet 10 is 300 to 600 ° C.
  • the heat insulating sheet according to the present embodiment by forming the surface layer with fibers, a filler, and a binder, a high heat resistant temperature can be exhibited, and the insulating property can be maintained even in a high temperature environment. Further, it is preferable to suppress the ashed area on the back surface to 500 mm 2 or less when heated for 10 minutes according to the JIS L 1091 A-1 method (1999) test.
  • the smoothness of the entire heat insulating sheet is 15 to 150 sec. This has the advantage that the heat insulating sheet does not need to be sealed and can be manufactured easily and inexpensively.
  • the heat insulating sheet according to the present embodiment can be provided with deformable flexibility.
  • it has a flexibility that does not break even when wound around a paper tube having a radius of curvature of 55 mm.
  • the object with which the heat insulating sheet is in contact is deformed, such as by expanding, it is possible to maintain the close contact state by following the deformation, and it is possible to avoid the situation where voids are formed and the thermal conductivity is lowered.
  • the heat insulating sheet 10 is a roll-to-roll by sandwiching a heat-sealing sheet between, for example, a roll-shaped intermediate layer 11 and a surface layer 12, passing between two thermocompression bonding rolls, and adhering them. It can be manufactured. Further, a liquid adhesive may be applied to one or both sides of the intermediate layer 11 to the surface layer 12 and bonded to each other.
  • a polyethylene heat-sealing sheet is sandwiched between the intermediate layer 11 and the surface layer 12, and is pressed and bonded at 50 kPa for 20 seconds with a hot press at 150 ° C. rice field.
  • the present invention is not limited to such a three-layer structure, and may be a multi-layer structure having four or more layers, for example, a surface layer having a plurality of layers or an intermediate layer having a plurality of layers.
  • a two-layer structure in which a surface layer is provided on only one side of the intermediate layer may be used.
  • the secondary battery cell 1 is placed in a vertical position, but it goes without saying that the heat insulating sheet can be similarly applied to a power supply device in which the secondary battery cell is placed in a horizontal position.
  • the heat insulating sheet 10 can be used not only for heat insulation between secondary battery cells but also for heat insulation between battery modules composed of a plurality of secondary battery cells. [Examples 1 to 4; Comparative Example 1]
  • Example 1 the same sheet made of natural pulp, microglass, silicate mineral powder and a rubber-based resin as a binder was used as the surface layer.
  • the papermaking slurry obtained by adding a rubber-based resin to this was made by a wet papermaking method to obtain a surface layer base material sheet having a thickness of about 0.70 mm.
  • the thermal conductivity (thickness direction) of this surface layer base material sheet is 0.18 W / m ⁇ K
  • the thermal conductivity (plane direction) is 0.18 W / m ⁇ K
  • the smoothness is 46.8 sec
  • the air permeability resistance The degree was 30 sec / 100 ml.
  • a papermaking sheet containing 90% graphite powder was used as the intermediate layer of Example 1. Specifically, a papermaking slurry in which graphite powder and organic fibers are dispersed in water so as to have a weight ratio of 90:10 is prepared, and the sheet obtained by the wet papermaking method is subjected to thermal pressure processing to obtain an intermediate layer base material. I got a sheet. Its thickness was 0.23 mm.
  • Example 2 A surface layer is laminated on both sides of the obtained intermediate layer base material sheet, a polyethylene heat-sealing sheet is sandwiched between the surface layer and the intermediate layer, and a pressure is applied at 50 kPa for 20 seconds by a hot press at 150 ° C.
  • the heat insulating sheet according to Example 1 was obtained. (Example 2)
  • Example 3 As the intermediate layer of Example 2, a papermaking slurry in which graphite powder and organic fibers were dispersed in water so as to have a weight ratio of 75:25 was prepared, and the sheet obtained by the wet papermaking method was subjected to thermal pressure processing. A surface layer base material sheet 2 was obtained. Its thickness was 0.07 mm. A surface layer was laminated on both sides of the obtained intermediate layer base material sheet in the same manner as in Example 1 to obtain a heat insulating sheet according to Example 2. (Example 3)
  • the intermediate layer of Example 3 was an aluminum film.
  • a shim plate aluminum TA200-300-02 manufactured by Iwata Seisakusho with a thickness of 0.2 mm was used as an intermediate layer base material sheet.
  • the surface layer of this intermediate layer base material sheet was bonded to each surface in the same manner as in Example 1 and the like to obtain a heat insulating sheet according to Example 3. (Example 4)
  • Example 4 A thin aluminum film was used as the intermediate layer of Example 4.
  • a shim plate aluminum TA200-300-01 manufactured by Iwata Seisakusho with a thickness of 0.1 mm was used as an intermediate layer base material sheet.
  • the surface layer of this intermediate layer base material sheet was bonded to each surface in the same manner as in Example 1 and the like to obtain a heat insulating sheet according to Example 4. (Comparative Example 1)
  • a heat-insulating papermaking sheet was used as in the surface layer.
  • the papermaking slurry obtained by mixing the raw materials in the same weight ratio as in Example 1 was made by a wet papermaking method to obtain an intermediate layer base material sheet having a thickness of about 0.3 mm.
  • the obtained intermediate layer base material sheet was laminated with surface layers on both sides in the same manner as in Example 1 and the like to obtain a heat insulating sheet according to Comparative Example 1.
  • Table 1 shows the thickness of the intermediate layer, the thickness of the entire heat insulating sheet, and the thermal conductivity (thickness direction and surface direction) of the heat insulating sheets according to Examples 1 to 4 and Comparative Example 1.
  • the front and back temperature evaluation test of the samples was first performed. Specifically, as shown in the side view of FIG. 6A, a ceramic heater HT (MS-1000 manufactured by Sakaguchi Electric Heat Co., Ltd.) is fixed to one side of the sample of the heat insulating sheet 10 with aluminum tape, and the upper surface of the heater HT and the heater HT are fixed. Thermocouples T0, T1, T2, and T3 were attached to the opposite surface of the heat insulating sheet 10 in contact with the heat as shown in FIGS. 6B and 6C. In this state, the temperature difference between the front and back of the heat insulating sheet was measured from the difference between the heater temperature and the back surface temperature of the sheet when the heater HT was raised to 200 ° C. with an output of 9.5 W to 20 W. (Flexibility test)
  • the heat insulating sheets according to Examples 1 to 4 and Comparative Example 1 were tested for flexibility. Specifically, a heat insulating sheet cut into 120 mm ⁇ 65 mm was pressed against the outer periphery of a paper tube having an outer diameter of 110 mm, and it was confirmed whether damage such as wrinkles or cracks occurred and evaluated. The evaluation was described in three stages as follows. ⁇ : Does not occur, ⁇ : Minor damage, ⁇ : Serious damage that makes it unusable. These results are shown in Table 2.
  • Example 3 in which aluminum is used for the intermediate layer has a larger temperature difference between the front and back surfaces than Examples 1 and 2 in which graphite powder is used, in other words, the heat insulating effect is higher.
  • Example 4 also exhibits a high heat insulating effect, although it is inferior to Example 3.
  • the aluminum of Examples 3 and 4 has the same thermal conductivity in the thickness direction and the surface direction and has no anisotropy, while the heat diffusion layer using the graphite powder of Examples 1 and 2 is shown in Table 1. As such, the thermal conductivity in the plane direction is 40 to 60 times higher than that in the thickness direction.
  • FIGS. 7A to 11B The photographs taken by the thermography camera are shown in FIGS. 7A to 11B.
  • FIG. 7A is a photograph of the sample of Example 1 taken from the heater surface
  • FIG. 7B is a photograph taken from the back surface side by a thermography camera.
  • FIG. 8A is a photograph of the sample of Example 2 taken from the heater surface
  • FIG. 8A is a photograph of the sample of Example 2 taken from the heater surface
  • FIG. 8B is a photograph taken from the back surface side with a thermography camera.
  • FIG. 9A is the heater surface of the sample of Example 3
  • FIG. 9B is the back surface side
  • FIG. 10A is the heater surface of the sample of Example 4
  • FIG. 10B is the back surface side
  • FIG. 11A is the heater surface of the sample of Comparative Example 1.
  • 11B is a photograph of the back surface side, respectively. From these figures, in Comparative Example 1 composed of only the heat insulating layer, the back surface side is hot as shown in FIG. 11B, whereas in Examples 1 to 4 in which both sides of the heat diffusion layer are covered with the heat insulating layer. It was confirmed that the temperature rise on the back surface side was suppressed in both cases.
  • Example 1 in which the thickness is relatively large, as compared with Example 2 in which the thickness is relatively large, the temperature rise is suppressed, the local temperature change is also suppressed, and uniform heat dissipation in the surface direction is achieved. It was confirmed that. (600 ° C combustion test)
  • each sample is attached to the jig at an angle of 45 ° as shown in Fig. 12, and the thermocouple is attached to the flame contact part of the gas burner GB and its back surface.
  • TC1 and TC2 were attached respectively, the flame of the gas burner GB was applied, the temperature of the thermocouple TC2 on the back surface at the time when the thermocouple TC1 of the flame contact portion reached 600 ° C. was measured, and the temperature difference was calculated.
  • each sample attached to the jig without a thermocouple was exposed to the flame of the gas burner GB for 10 minutes, the presence or absence of combustion was observed, the state of both sides of the sample after the test was photographed, and the organic component was burned.
  • the area was measured using the image processing software "leafareacounter_plus3_3".
  • the image processing software as for the ashed area, as shown by the red line in FIG. 13A, the area where the organic component disappeared by combustion and only the inorganic component was ashed white was measured.
  • the area burnt black including the ashed area was measured so as to be surrounded by the red line in FIG. 13B.
  • FIGS. 14A to 18B The photographs of the samples of Examples 1 to 4 and Comparative Example 1 after the combustion test are shown in FIGS. 14A to 18B, respectively.
  • FIG. 14A is a photograph of the combustion surface of the sample of Example 1
  • FIG. 14B is a photograph of the back surface
  • FIG. 15A is a photograph of the combustion surface of the sample of Example 2
  • FIG. 15B is a photograph of the back surface
  • FIG. 16A is a photograph of Example 3.
  • the combustion surface of the sample FIG. 16B is a photograph of the back surface
  • FIG. 17A is a photograph of the combustion surface of the sample of Example 4
  • FIG. 17B is a photograph of the back surface
  • FIG. 18A is a photograph of the combustion surface of the sample of Comparative Example 1
  • FIG. 18B is a photograph of the back surface.
  • Comparative Example 1 composed of only the heat insulating layer, as shown in FIG. 18A, it is confirmed that the portion of the combustion surface that seems to have been exposed to the flame is ashed white. It is presumed that this is because the organic component burned and only the inorganic component remained in the spot shape. Also on the back surface side, as shown in FIG. 18B, a similarly whitish ashed state was confirmed at the corresponding portion. Similarly, it is considered that the organic component is burned and only the inorganic component remains in the spot shape.
  • Example 1 and 2 coated with the heat diffusion layer of graphite powder the state of combustion was not confirmed on the combustion surface, and black soot like slightly burnt was confirmed as shown in FIGS. 14A and 15A. rice field. Further, on the back surface side as well, in Example 1, only the occurrence of some wrinkles is confirmed as shown in FIG. 14B. It is considered that this is because the resin of the adhesive material was softened by heat and wrinkles were generated.
  • Example 2 as shown in FIG. 15B, although the occurrence of wrinkles was confirmed, the state of combustion was not confirmed. As described above, in Examples 1 and 2, it was confirmed that the heat conduction to the back surface side was suppressed even if the front surface side was exposed to the flame.
  • Table 4 shows a summary of these test results. As described above, it was confirmed that Examples 1 to 4 are superior in flame retardancy as compared with Comparative Example 1.
  • Example 5 papermaking was carried out in the same manner as in Example 1 except that the thickness was 0.30 mm, and a surface layer base material sheet was obtained. Using the obtained surface layer base material sheet, it was laminated on both sides of the intermediate layer base material sheet similar to that of Example 1 and bonded in the same manner as in Example 1 to obtain a heat insulating sheet according to Example 5. (Example 6)
  • Example 6 In order to prepare the surface layer of Example 6, first, the dissociated natural pulp was prepared, and microglass, chopped glass, synthetic silica and diatomaceous earth were uniformly dispersed. A rubber-based resin was added thereto, and paper was made by a wet papermaking method to obtain a surface layer base material sheet having a thickness of about 0.80 mm. The thermal conductivity (thickness direction) of this sheet was 0.08 W / m ⁇ K, and the thermal conductivity (plane direction) was 0.08 W / m ⁇ K. Using the obtained surface layer base material sheet, it was laminated on both sides of the intermediate layer base material sheet similar to that of Example 1 and bonded in the same manner as in Example 1 to obtain a heat insulating sheet according to Example 6. (Comparative Example 2)
  • the smoothness was measured for each sample of Examples 1, 5, 6 and Comparative Example 2.
  • a decibel smoothness tester (DB-2 type manufactured by Toyo Seiki Seisakusho) conforming to JIS P 8119 (1998) was used.
  • the volume of the vacuum container is 380 mL, which is the JIS standard 8.
  • the test start pressure was 50.7 KPa and the test end pressure was 29.3 KPa.
  • the standard test start pressure is 50.7 KPa and the test end pressure is 48.0 KPa, but since the measurement time was shorter than 15 seconds under this condition, the test end pressure was changed to a lower value. And are testing.
  • Table 4 Since Comparative Example 2 had extremely high smoothness, the measurement was stopped when the measured value was 3000 sec. (Bubble point test and pore diameter)
  • Example 1 the bubble point value of the surface layer base material sheet before being bonded to the intermediate layer was measured according to JIS K 3832 (1990), and the pore diameter was calculated. Specifically, a sample of the surface layer cut into 4 cm ⁇ 4 cm is immersed in a test solution made of Fluorinert FC-40 having a surface tension of 16 mN / m, and the sample completely filled with the test solution is a palm poromometer. The measurement was performed by attaching to CFP-1100AE (manufactured by Polouse Materials Inc.). From the obtained bubble point value, the pore diameter d [ ⁇ m] was calculated by the following formula. The results are shown in Table 4.
  • Example 1 a Garley standard type densometer compliant with the JIS P 8117 (2009) test was used to determine the air permeability resistance of the surface layer base material sheet before being bonded to the intermediate layer. was measured. The results are shown in Table 4.
  • Comparative Example 2 the air permeability resistance was extremely high, and the measurement was stopped when the measured value was 6000 sec / ml. (Compression / recovery rate)
  • the compressibility was measured when the pressure of the surface layer base material sheet before bonding with the intermediate layer was 100 kPa.
  • Instron's universal material testing machine type 5985 was used.
  • thermocouple TC1 was removed by allowing the sample to cool while attached to the jig, and the electrodes of the digital tester TST-KJ830 (manufactured by Ohm Electric) were applied to the flame contact part and the back surface to confirm whether the sample was conducting.
  • the results are shown in Table 5. ( ⁇ : no continuity, ⁇ : with continuity)
  • the heat insulating sheet of the present invention is used as a heat insulating spacer interposed between secondary battery cells, a cushioning sheet interposed between an explosion-proof valve and a gas duct, or a heat insulating material for protecting a drive circuit such as an ECU. It can be suitably used.
  • Power supply devices using heat insulating sheets include mobile electronic devices, power devices driven by battery-powered motors, electric vehicles such as electric vehicles and hybrid vehicles, electric two-wheeled vehicles such as assisted bicycles and electric scooters, electric golf carts and drones. , Can be suitably used for power storage systems and the like.

Abstract

Provided is an insulating sheet for which insulation performance is maintained while manufacturing costs are lowered. An insulating sheet (10) comprises a middle layer (11) and surface layers (12) layered on surfaces of the middle layer (11). The surface layers (12) have a heat conductivity of 0.50 W/m∙K or less in the direction of thickness, and the middle layer (11) has a heat conductivity of 1.00 W/m∙K or more in the direction of thickness. The pore diameter of the surface layers (12) may be 50 µm or less. This configuration imparts insulating properties to the surface layers (12) and consequently prevents fire from spreading, and eliminates the need to seal the surface layers (12), thus making it possible to provide the advantageous feature of being able to carry out production with ease and at a low cost.

Description

断熱シート及びこれを備える電源装置Insulation sheet and power supply equipped with it
　本発明は、断熱シート及びこれを備える電源装置に関する。 The present invention relates to a heat insulating sheet and a power supply device including the heat insulating sheet.
　断熱性を有するシート材が、二次電池セルの断熱や絶縁を図るスペーサ、防爆シート、あるいは冷蔵庫等の温度差のある部材を被覆するシート材など、様々な用途で用いられている。一例として、二次電池セルの断熱用スペーサについて説明する。二次電池セルを複数積層した電源装置が、電気自動車やハイブリッド自動車、電動バス、電車等の電動車両の駆動用電源として、あるいは工場や基地局のバックアップ電源用、さらには家庭用の蓄電池として用いられている（例えば特許文献１、２）。近年は電源装置の軽量化、及び高容量化が求められており、二次電池セルにはリチウムイオン二次電池等の高容量のタイプが用いられている。 Sheet materials with heat insulating properties are used in various applications such as spacers for heat insulation and insulation of secondary battery cells, explosion-proof sheets, and sheet materials for covering members with different temperatures such as refrigerators. As an example, a spacer for heat insulation of a secondary battery cell will be described. A power supply device in which multiple secondary battery cells are stacked is used as a power source for driving electric vehicles such as electric vehicles, hybrid vehicles, electric buses, and trains, as a backup power source for factories and base stations, and as a storage battery for home use. (For example, Patent Documents 1 and 2). In recent years, there has been a demand for weight reduction and high capacity of power supply devices, and high capacity types such as lithium ion secondary batteries are used for secondary battery cells.
　一方で、二次電池セルを多数用いた場合、何らかの異常により一の二次電池セルが高温になって熱暴走し、隣接する他の二次電池セルに高温が伝搬して熱暴走が連鎖的に発生する類焼と呼ばれる現象が発生することがある。特にリチウムイオン二次電池のような高容量の電池の場合は、エネルギー容量が大きい分だけ、発熱量も大きくなる。このため、安全性確保の観点から、このような類焼の発生を抑制することが希求されている。 On the other hand, when a large number of secondary battery cells are used, one secondary battery cell becomes hot due to some abnormality and causes thermal runaway, and the high temperature propagates to other adjacent secondary battery cells, resulting in a chain of thermal runaway. A phenomenon called smoldering that occurs in the battery may occur. In particular, in the case of a high-capacity battery such as a lithium-ion secondary battery, the amount of heat generated increases as the energy capacity increases. Therefore, from the viewpoint of ensuring safety, it is desired to suppress the occurrence of such burning.
　熱暴走の抑制には、断熱性能の向上が効果的と思われる。断熱性能の向上とは、熱伝導率を低くすることである。したがって、二次電池セルを積層した電源装置において類焼の発生を阻止するには、二次電池セル同士の間に、絶縁シートを介在させることが考えられる。 It seems that improving the heat insulation performance is effective in suppressing thermal runaway. Improving the heat insulation performance means lowering the thermal conductivity. Therefore, in order to prevent the occurrence of burning in the power supply device in which the secondary battery cells are stacked, it is conceivable to interpose an insulating sheet between the secondary battery cells.
　一方で、本発明者が熱暴走の発生プロセスを検討していくと、複数の二次電池セルのいずれかで、当該二次電池セルの一部が局所的に高温になるホットスポットが発生し、この部分から高熱が隣接する二次電池セルに伝搬して類焼が広がっていくとの知見を得た。 On the other hand, when the present inventor examined the process of generating thermal runaway, a hot spot in which a part of the secondary battery cell became locally hot was generated in any of the plurality of secondary battery cells. It was found that high heat propagates from this part to the adjacent secondary battery cell and the burning spreads.
　しかしながら、類焼防止の観点から断熱性能を向上させると、熱伝導率が低いことから、図４の模式断面図に示すように、いずれかの二次電池セル１にホットスポットＨＳが発生しても、この高熱を断熱シート１０Ｘで熱伝導して放熱することができず、結果的に高温の発生を抑制できずに熱暴走が発生してしまう。かといって、熱伝導率を上げると、断熱性能を発揮できなくなって隣接する二次電池セルに高温が伝搬してしまい、類焼の発生を抑制できない。このように、ホットスポットの発生の抑制と類焼の防止とは、相反する特性であって両立させることが困難であった。 However, if the heat insulating performance is improved from the viewpoint of preventing burning, the thermal conductivity is low. Therefore, as shown in the schematic cross-sectional view of FIG. 4, even if hot spot HS occurs in any of the secondary battery cells 1. This high heat cannot be thermally conducted and dissipated by the heat insulating sheet 10X, and as a result, the generation of high temperature cannot be suppressed and thermal runaway occurs. However, if the thermal conductivity is increased, the heat insulating performance cannot be exhibited and the high temperature propagates to the adjacent secondary battery cells, and the occurrence of burning cannot be suppressed. As described above, the suppression of the generation of hot spots and the prevention of burning are contradictory characteristics, and it is difficult to achieve both.
　これに対して、二次電池セル同士の間に、断熱層とその両側に配置した熱伝導シートを含む複合シートとする構成が提案されている（特許文献２）。これによれば、電池セルから筐体への放熱性に優れると共に、隣接する電池セル間の断熱性に優れるとされている。 On the other hand, a configuration has been proposed in which a composite sheet including a heat insulating layer and heat conductive sheets arranged on both sides thereof is formed between the secondary battery cells (Patent Document 2). According to this, it is said that the heat dissipation from the battery cell to the housing is excellent and the heat insulation between adjacent battery cells is excellent.
　しかしながら、この構成では熱伝導シートにグラファイトを用いているところ、グラファイトシートからは、導電性を有するグラファイト粉末が発生する可能性がある。このようなグラファイト粉末は、電子回路に付着してショートなどの不具合を引き起こす可能性があった。このため、図１９に示すように、断熱層９５を備える複合シートにおいて、熱伝導シート９２を構成するグラファイトシートよりも寸法の大きい第１の絶縁シート９３と第２の絶縁シート９４を用いてグラファイトシートを挟み込み、グラファイトシートの外周縁の外側で封止する必要があった。このような封止のための加工は手間がかかり、コストも増す。また部品点数を増やす上、複合シートの厚膜化にもつながる。特に車載用の電源装置においては、高出力化と共に小型化が強く求められているところ、高出力化のために二次電池セルの積層数が増えると、これに応じて二次電池セル同士の間に介在させる複合シートの枚数も増え、電源装置全体が厚くなる上、重量の増大や加工コストも含めた製造コストの高騰にもつながるという問題があった。 However, in this configuration, when graphite is used for the heat conductive sheet, there is a possibility that graphite powder having conductivity will be generated from the graphite sheet. Such graphite powder may adhere to electronic circuits and cause problems such as short circuits. Therefore, as shown in FIG. 19, in the composite sheet provided with the heat insulating layer 95, graphite is used by using the first insulating sheet 93 and the second insulating sheet 94 having larger dimensions than the graphite sheet constituting the heat conductive sheet 92. It was necessary to sandwich the sheet and seal it on the outside of the outer periphery of the graphite sheet. Processing for such sealing is laborious and costly. In addition to increasing the number of parts, it also leads to a thicker composite sheet. In particular, in an in-vehicle power supply device, there is a strong demand for miniaturization as well as high output. However, when the number of stacked secondary battery cells increases due to high output, the secondary battery cells become compatible with each other. There is a problem that the number of composite sheets intervening between them increases, the entire power supply device becomes thicker, the weight increases, and the manufacturing cost including the processing cost rises.
　また、この構成では絶縁シートにポリエチレンテレフタレート(以下ＰＥＴと記す)フィルムを、断熱層に、シリカキセロゲルを含浸したＰＥＴ不織布を用いているところ、ホットスポットの熱で収縮、穿孔が生じ、いずれは隣接するセル間の絶縁を保持できなくなるという問題もあった。 Further, in this configuration, when a polyethylene terephthalate (hereinafter referred to as PET) film is used for the insulating sheet and a PET non-woven fabric impregnated with silica xerogel is used for the heat insulating layer, shrinkage and perforation occur due to the heat of the hot spot, and eventually they are adjacent to each other. There was also a problem that the insulation between the cells could not be maintained.
特許５７４０１０３号公報Japanese Patent No. 5740103 ＷＯ２０１７／１５９５２７号WO2017 / 159527
　本発明は、このような背景に鑑みてなされたものであり、その目的の一は、断熱性能を維持しつつも加工コストを削減した断熱シート及びこれを備える電源装置を提供することにある。 The present invention has been made in view of such a background, and one of the purposes thereof is to provide a heat insulating sheet having reduced processing costs while maintaining heat insulating performance and a power supply device provided with the heat insulating sheet.
課題を解決するための手段及び発明の効果Means for Solving Problems and Effects of Invention
　本発明の第１の形態に係る断熱シートによれば、中間層と、前記中間層の表面に積層された表面層と、を備え、前記表面層の、厚さ方向の熱伝導率が、０．５０Ｗ／ｍ・Ｋ以下であり、前記中間層の、厚さ方向の熱伝導率が、１．００Ｗ／ｍ・Ｋ以上であり、前記表面層の細孔径を５０μｍ以下とすることができる。上記構成により、表面層に断熱性を持たせて類焼を防止しつつ、表面層の封止を不要として製造を容易にかつ安価に行える利点が得られる。 According to the heat insulating sheet according to the first aspect of the present invention, the heat insulating sheet includes an intermediate layer and a surface layer laminated on the surface of the intermediate layer, and the thermal conductivity of the surface layer in the thickness direction is 0. The thermal conductivity of the intermediate layer in the thickness direction is 1.00 W / m · K or more, and the pore diameter of the surface layer can be 50 μm or less. With the above configuration, it is possible to obtain an advantage that the surface layer can be easily and inexpensively manufactured without the need for sealing the surface layer while providing heat insulating properties to prevent burning.
　また、本発明の第２の形態に係る断熱シートによれば、上記いずれかの構成に加えて、中間層と、前記中間層の表面に積層された表面層と、を備え、前記表面層の、厚さ方向の熱伝導率が、０．５０Ｗ／ｍ・Ｋ以下であり、前記中間層の、厚さ方向の熱伝導率が、１．００Ｗ／ｍ・Ｋ以上であり、前記表面層の透気抵抗度が、ＪＩＳ　Ｐ　８１１７（２００９）試験に準拠したガーレー標準形デンソメータで３～５０００ｓｅｃ／１００ｍＬとすることができる。上記構成により、表面層に断熱性を持たせて類焼を防止しつつ、表面層の封止を不要として製造を容易にかつ安価に行える利点が得られる。 Further, according to the heat insulating sheet according to the second aspect of the present invention, in addition to any of the above configurations, an intermediate layer and a surface layer laminated on the surface of the intermediate layer are provided, and the surface layer is provided with the intermediate layer. The thermal conductivity in the thickness direction is 0.50 W / m · K or less, the thermal conductivity in the thickness direction of the intermediate layer is 1.00 W / m · K or more, and the surface layer is The air permeation resistance can be set to 3 to 5000 sec / 100 mL with a Garley standard type densometer conforming to the JIS P 8117 (2009) test. With the above configuration, it is possible to obtain an advantage that the surface layer can be easily and inexpensively manufactured without the need for sealing the surface layer while providing heat insulating properties to prevent burning.
　さらに、本発明の第３の形態に係る断熱シートによれば、上記いずれかの構成に加えて、前記表面層を、前記中間層の両面にそれぞれ積層することができる。 Further, according to the heat insulating sheet according to the third aspect of the present invention, in addition to any of the above configurations, the surface layer can be laminated on both sides of the intermediate layer.
　さらにまた、本発明の第４の形態に係る断熱シートによれば、上記いずれかの構成に加えて、前記中間層の、面方向の熱伝導率を、１０００Ｗ／ｍ・Ｋ以下とすることができる。 Furthermore, according to the heat insulating sheet according to the fourth aspect of the present invention, in addition to any of the above configurations, the thermal conductivity of the intermediate layer in the plane direction may be 1000 W / m · K or less. can.
　さらにまた、本発明の第５の形態に係る断熱シートによれば、上記いずれかの構成に加えて、前記中間層の、厚さ方向の熱伝導率を、３．００Ｗ／ｍ・Ｋ以下とすることができる。 Furthermore, according to the heat insulating sheet according to the fifth aspect of the present invention, in addition to any of the above configurations, the thermal conductivity of the intermediate layer in the thickness direction is set to 3.00 W / m · K or less. can do.
　さらにまた、本発明の第６の形態に係る断熱シートによれば、上記いずれかの構成に加えて、前記中間層の、面方向の熱伝導率を、厚さ方向の熱伝導率の５倍以上とすることができる。上記構成により、面方向において部分的に高温の部位が発生しても、面方向に熱伝導させてホットスポットの発生を抑制し、もって類焼の発生を抑制できる。 Furthermore, according to the heat insulating sheet according to the sixth aspect of the present invention, in addition to any of the above configurations, the thermal conductivity in the plane direction of the intermediate layer is five times the thermal conductivity in the thickness direction. The above can be done. With the above configuration, even if a hot spot is partially generated in the surface direction, heat is conducted in the surface direction to suppress the generation of hot spots, and thus the generation of burning can be suppressed.
　さらにまた、本発明の第７の形態に係る断熱シートによれば、上記いずれかの構成に加えて、前記中間層を、抄紙シートで構成することができる。 Furthermore, according to the heat insulating sheet according to the seventh aspect of the present invention, in addition to any of the above configurations, the intermediate layer can be composed of a papermaking sheet.
　さらにまた、本発明の第８の形態に係る断熱シートによれば、上記いずれかの構成に加えて、前記中間層が、繊維又は熱伝導フィラーを含むことができる。 Furthermore, according to the heat insulating sheet according to the eighth aspect of the present invention, in addition to any of the above configurations, the intermediate layer can contain fibers or a heat conductive filler.
　さらにまた、本発明の第９の形態に係る断熱シートによれば、上記いずれかの構成に加えて、前記中間層が、グラファイト、窒化硼素、アルミニウムのいずれかを含むことができる。 Furthermore, according to the heat insulating sheet according to the ninth aspect of the present invention, in addition to any of the above configurations, the intermediate layer can contain any of graphite, boron nitride, and aluminum.
　さらにまた、本発明の第１０の形態に係る断熱シートによれば、上記いずれかの構成に加えて、ＪＩＳ　Ｌ　１０９１　Ａ－１法（１９９９）試験に準じて１０分間加熱した際における裏面の灰化面積を５００ｍｍ2以下とすることができる。 Furthermore, according to the heat insulating sheet according to the tenth aspect of the present invention, in addition to any of the above configurations, the ash on the back surface when heated for 10 minutes according to the JIS L 1091 A-1 method (1999) test. The conversion area can be 500 mm 2 or less.
　さらにまた、本発明の第１１の形態に係る断熱シートによれば、上記いずれかの構成に加えて、前記表面層の体積抵抗率を１０10以上とすることができる。上記構成により、燃焼後の絶縁性を保持することができる。 Furthermore, according to the heat insulating sheet according to the eleventh embodiment of the present invention, the volume resistivity of the surface layer can be set to 10 10 or more in addition to any of the above configurations. With the above configuration, the insulation after combustion can be maintained.
　さらにまた、本発明の第１２の形態に係る断熱シートによれば、上記いずれかの構成に加えて、前記表面層が、繊維、充填材、バインダの少なくともいずれかを含むことができる。上記構成により、表面層からの粉落ちを避けることが可能となる。 Furthermore, according to the heat insulating sheet according to the twelfth aspect of the present invention, in addition to any of the above configurations, the surface layer can contain at least one of fibers, a filler, and a binder. With the above configuration, it is possible to prevent powder from falling from the surface layer.
　さらにまた、本発明の第１３の形態に係る断熱シートによれば、上記いずれかの構成に加えて、前記中間層と表面層を接着する接着層が、アクリル系接着材、塩化ビニル系接着材、酢酸ビニル系接着材、ホットメルトの少なくともいずれかとすることができる。 Furthermore, according to the heat insulating sheet according to the thirteenth aspect of the present invention, in addition to any of the above configurations, the adhesive layer for adhering the intermediate layer and the surface layer is an acrylic adhesive or a vinyl chloride adhesive. , Vinyl acetate-based adhesive, or at least one of hot melt.
　さらにまた、本発明の第１４の形態に係る断熱シートによれば、上記いずれかの構成に加えて、厚さを０．２ｍｍ～６．０ｍｍとすることができる。 Furthermore, according to the heat insulating sheet according to the fourteenth aspect of the present invention, the thickness can be 0.2 mm to 6.0 mm in addition to any of the above configurations.
　さらにまた、本発明の第１５の形態に係る断熱シートによれば、上記いずれかの構成に加えて、前記表面層を、１００ｋＰａで圧縮した時の圧縮率を１０％以上とすることができる。 Furthermore, according to the heat insulating sheet according to the fifteenth aspect of the present invention, in addition to any of the above configurations, the compression rate when the surface layer is compressed at 100 kPa can be set to 10% or more.
　さらにまた、本発明の第１６の形態に係る断熱シートによれば、上記いずれかの構成に加えて、耐熱温度を３００～６００℃とすることができる。 Furthermore, according to the heat insulating sheet according to the sixteenth aspect of the present invention, the heat resistant temperature can be set to 300 to 600 ° C. in addition to any of the above configurations.
　さらにまた、本発明の第１７の形態に係る断熱シートによれば、上記いずれかの構成に加えて、複数の二次電池セルを積層した電源装置に用いる断熱シートであって、中間層と、前記中間層の表面にそれぞれ積層された表面層と、を備え、前記表面層の、厚さ方向の熱伝導率が、０．５０Ｗ／ｍ・Ｋ以下であり、前記中間層の、厚さ方向の熱伝導率が、１．００Ｗ／ｍ・Ｋ以上であり、前記表面層の細孔径を５０μｍ以下とすることができる。 Furthermore, according to the heat insulating sheet according to the seventeenth aspect of the present invention, in addition to any of the above configurations, a heat insulating sheet used for a power supply device in which a plurality of secondary battery cells are laminated, the heat insulating sheet and the intermediate layer. A surface layer laminated on the surface of the intermediate layer is provided, and the thermal conductivity of the surface layer in the thickness direction is 0.50 W / m · K or less, and the heat conductivity of the surface layer is 0.50 W / m · K or less in the thickness direction. The thermal conductivity of the surface layer is 1.00 W / m · K or more, and the pore diameter of the surface layer can be 50 μm or less.
　さらにまた、本発明の第１８の形態に係る電源装置によれば、上記いずれかの断熱シートと、前記断熱シートを介在させて積層した複数の二次電池セルとを備えることができる。 Furthermore, according to the power supply device according to the eighteenth aspect of the present invention, any one of the above heat insulating sheets and a plurality of secondary battery cells laminated with the heat insulating sheet interposed therebetween can be provided.
実施形態１に係る断熱シートを用いた電源装置を示す斜視図である。It is a perspective view which shows the power supply apparatus which used the heat insulating sheet which concerns on Embodiment 1. FIG. 図１の電源装置のＩＩ－ＩＩ線における垂直断面図である。FIG. 3 is a vertical sectional view taken along line II-II of the power supply device of FIG. 実施形態１に係る断熱シートを示す拡大模式断面図である。FIG. 3 is an enlarged schematic cross-sectional view showing a heat insulating sheet according to the first embodiment. 二次電池セル同士の間を従来の断熱シートで断熱した構成において、ホットスポットが発生した状態を示す模式断面図である。It is a schematic cross-sectional view which shows the state which the hot spot occurred in the structure which insulated between the secondary battery cells with the conventional heat insulating sheet. パウチ型二次電池セル同士の間を実施形態１に係る断熱シートで断熱した構成において、ホットスポットが発生した状態を示す模式断面図である。It is a schematic cross-sectional view which shows the state which hot spot occurred in the structure which insulated between pouch type secondary battery cells by the heat insulating sheet which concerns on Embodiment 1. FIG. 図６Ａは表裏温度評価試験においてセラミックヒーターと熱電対の取付位置を示す側面図、図６Ｂはヒーター上面における熱電対の取付位置を示す平面図、図６Ｃはサンプル裏面側の熱電対の取付位置を示す底面図である。FIG. 6A is a side view showing the mounting position of the ceramic heater and the thermocouple in the front and back temperature evaluation test, FIG. 6B is a plan view showing the mounting position of the thermocouple on the upper surface of the heater, and FIG. 6C shows the mounting position of the thermocouple on the back side of the sample. It is a bottom view which shows. 図７Ａは実施例１のサンプルをヒーター面から、図７Ｂは裏面側から、それぞれサーモグラフィカメラで撮像した写真である。FIG. 7A is a photograph of the sample of Example 1 taken from the heater surface, and FIG. 7B is a photograph taken from the back surface side with a thermography camera. 図８Ａは実施例２のサンプルをヒーター面から、図８Ｂは裏面側から、それぞれサーモグラフィカメラで撮像した写真である。FIG. 8A is a photograph of the sample of Example 2 taken from the heater surface, and FIG. 8B is a photograph taken from the back surface side with a thermography camera. 図９Ａは実施例３のサンプルのヒーター面を、図９Ｂは裏面側を、それぞれサーモグラフィカメラで撮像した写真である。FIG. 9A is a photograph of the heater surface of the sample of Example 3, and FIG. 9B is a photograph of the back surface side of the sample, respectively, taken by a thermography camera. 図１０Ａは実施例４のサンプルのヒーター面を、図１０Ｂは裏面側を、それぞれサーモグラフィカメラで撮像した写真である。FIG. 10A is a photograph of the heater surface of the sample of Example 4, and FIG. 10B is a photograph of the back surface side of the sample, respectively, taken by a thermography camera. 図１１Ａは比較例１のサンプルのヒーター面を、図１１Ｂは裏面側を、それぞれサーモグラフィカメラで撮像した写真である。FIG. 11A is a photograph of the heater surface of the sample of Comparative Example 1 and FIG. 11B is a photograph of the back surface side of the sample taken by a thermography camera. サンプルの燃焼試験を示す模式図である。It is a schematic diagram which shows the combustion test of a sample. 図１３Ａは画像処理ソフトで灰化面積を測定する様子を示す写真、図１３Ｂは炭化面積を測定する様子を示す写真である。FIG. 13A is a photograph showing how the incinerated area is measured by the image processing software, and FIG. 13B is a photograph showing how the carbonized area is measured. 図１４Ａは燃焼試験後の実施例１のサンプルの燃焼面を、図１４Ｂは裏面を、それぞれ撮像した写真である。FIG. 14A is a photograph of the combustion surface of the sample of Example 1 after the combustion test, and FIG. 14B is a photograph of the back surface of the sample. 図１５Ａは燃焼試験後の実施例２のサンプルの燃焼面を、図１５Ｂは裏面の写真を、それぞれ撮像した写真である。FIG. 15A is a photograph of the combustion surface of the sample of Example 2 after the combustion test, and FIG. 15B is a photograph of the back surface of the sample. 図１６Ａは燃焼試験後の実施例３のサンプルの燃焼面を、図１６Ｂは裏面の写真を、それぞれ撮像した写真である。FIG. 16A is a photograph of the combustion surface of the sample of Example 3 after the combustion test, and FIG. 16B is a photograph of the back surface of the sample. 図１７Ａは燃焼試験後の実施例４のサンプルの燃焼面を、図１７Ｂは裏面の写真を、それぞれ撮像した写真である。FIG. 17A is a photograph of the combustion surface of the sample of Example 4 after the combustion test, and FIG. 17B is a photograph of the back surface of the sample. 図１８Ａは燃焼試験後の比較例１のサンプルの燃焼面を、図１８Ｂは裏面の写真を、それぞれ撮像した写真である。FIG. 18A is a photograph of the combustion surface of the sample of Comparative Example 1 after the combustion test, and FIG. 18B is a photograph of the back surface of the sample. 従来の複合シートを示す模式断面図である。It is a schematic cross-sectional view which shows the conventional composite sheet.
　以下、本発明の実施の形態を図面に基づいて説明する。ただし、以下に示す実施の形態は、本発明の技術思想を具体化するための例示であって、本発明は以下のものに限定されない。また、本明細書は特許請求の範囲に示される部材を、実施の形態の部材に特定するものでは決してない。特に実施の形態に記載されている構成部品の寸法、材質、形状、その相対的配置等は特定的な記載がない限りは、本発明の範囲をそれのみに限定する趣旨ではなく、単なる説明例にすぎない。なお、各図面が示す部材の大きさや位置関係等は、説明を明確にするため誇張していることがある。さらに以下の説明において、同一の名称、符号については同一もしくは同質の部材を示しており、詳細説明を適宜省略する。さらに、本発明を構成する各要素は、複数の要素を同一の部材で構成して一の部材で複数の要素を兼用する態様としてもよいし、逆に一の部材の機能を複数の部材で分担して実現することもできる。
［実施形態１］ Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, the embodiments shown below are examples for embodying the technical idea of the present invention, and the present invention is not limited to the following. Further, the present specification does not specify the members shown in the claims as the members of the embodiment. In particular, the dimensions, materials, shapes, relative arrangements, etc. of the components described in the embodiments are not intended to limit the scope of the present invention to the specific description, and are merely explanatory examples. It's just that. The size and positional relationship of the members shown in each drawing may be exaggerated for the sake of clarity. Further, in the following description, members of the same or the same quality are shown with the same name and reference numeral, and detailed description thereof will be omitted as appropriate. Further, each element constituting the present invention may be configured such that a plurality of elements are composed of the same member and the plurality of elements are combined with one member, or conversely, the function of one member is performed by the plurality of members. It can also be shared and realized.
[Embodiment 1]
　本発明の実施形態に係る断熱シートは、断熱性が求められる用途に適宜利用できる。例えば冷蔵庫や冷凍庫等を断熱する断熱材、建材用の断熱シート等に用いることができる。ここでは、二次電池セルを多数積層して直列や並列に接続した電源装置において、隣接する二次電池セル同士の間に介在されるスペーサとして、断熱シートを用いる例を説明する。このような電源装置は、電気自動車やハイブリッド自動車、電動バス、電車、電動カート等の電動車両の駆動用電源として、あるいは工場や基地局のバックアップ電源用、さらには家庭用の蓄電池として利用される。 The heat insulating sheet according to the embodiment of the present invention can be appropriately used for applications requiring heat insulating properties. For example, it can be used as a heat insulating material for insulating refrigerators, freezers, etc., a heat insulating sheet for building materials, and the like. Here, an example in which a heat insulating sheet is used as a spacer interposed between adjacent secondary battery cells in a power supply device in which a large number of secondary battery cells are stacked and connected in series or in parallel will be described. Such a power supply device is used as a power source for driving electric vehicles such as electric vehicles, hybrid vehicles, electric buses, trains, and electric carts, as a backup power source for factories and base stations, and as a storage battery for home use. ..
　実施形態１に係る断熱シートを用いた電源装置を、図１の斜視図及び図２の垂直断面図に示す。これらの図に示す電源装置１００は、複数の二次電池セル１と、二次電池セル１同士の間に介在される断熱シート１０とを備える。このように二次電池セル１と断熱シート１０とを交互に積層して、電池積層体を構成している。また電池積層体の側面には、必要に応じて側板２が配置される。側板２は、二次電池セル１の側面と熱的に結合されて、熱伝導により放熱する放熱板として機能する。
（断熱シート１０） A power supply device using the heat insulating sheet according to the first embodiment is shown in a perspective view of FIG. 1 and a vertical sectional view of FIG. The power supply device 100 shown in these figures includes a plurality of secondary battery cells 1 and a heat insulating sheet 10 interposed between the secondary battery cells 1. In this way, the secondary battery cell 1 and the heat insulating sheet 10 are alternately laminated to form a battery laminate. Further, a side plate 2 is arranged on the side surface of the battery laminate as needed. The side plate 2 is thermally coupled to the side surface of the secondary battery cell 1 and functions as a heat radiating plate that dissipates heat by heat conduction.
(Insulation sheet 10)
　隣接する二次電池セル１同士の間には、断熱シート１０が介在される。断熱シート１０は、スペーサやセパレータ等と呼ばれ、隣接する二次電池セル１間を断熱して類焼を防止または抑制するための部材である。また断熱シート１０は、その上端や下端、側面などを放熱板などと熱的に結合して、放熱部材として機能させることもできる。例えば電池積層体の上下に放熱フィンを配置し、断熱シートの上下端をそれぞれ放熱フィンと熱結合することができる。
（二次電池セル１） A heat insulating sheet 10 is interposed between the adjacent secondary battery cells 1. The heat insulating sheet 10 is called a spacer, a separator, or the like, and is a member for insulating between adjacent secondary battery cells 1 to prevent or suppress burning. Further, the heat insulating sheet 10 can be made to function as a heat radiating member by thermally coupling the upper end, the lower end, the side surface and the like with a heat radiating plate or the like. For example, heat dissipation fins can be arranged above and below the battery laminate, and the upper and lower ends of the heat insulating sheet can be thermally coupled to the heat dissipation fins, respectively.
(Secondary battery cell 1)
　二次電池セル１は、リチウムイオン二次電池が好適に利用できる。二次電池セル１は、外装材を導電性部材で構成している。このような二次電池セル１を複数枚積層して電池積層体を構成するには、断熱性に加えて絶縁性も求められる。本実施形態に係る断熱シート１０は、表面層１２を絶縁性を備えるシートで構成することで、このような導電性の外装缶を用いた二次電池セルを用いた電源装置に、好適に利用できる。なお本発明は、外装材を絶縁性とした二次電池セル、例えば外形を板状としたパウチ型やラミネート型と呼ばれるタイプに対しても利用できることはいうまでもない。
（断熱シート１０） As the secondary battery cell 1, a lithium ion secondary battery can be preferably used. The exterior material of the secondary battery cell 1 is made of a conductive member. In order to form a battery laminate by stacking a plurality of such secondary battery cells 1 together, insulation is required in addition to heat insulation. The heat insulating sheet 10 according to the present embodiment is suitably used for a power supply device using a secondary battery cell using such a conductive outer can by forming the surface layer 12 with a sheet having insulating properties. can. Needless to say, the present invention can also be used for a secondary battery cell having an insulating outer material, for example, a pouch type or a laminated type having a plate-shaped outer shape.
(Insulation sheet 10)
　断熱シート１０の拡大断面図を、図３に示す。この図に示す断熱シート１０は、中間層１１と、この中間層１１を挟むように、両面に積層された表面層１２で構成される。 An enlarged cross-sectional view of the heat insulating sheet 10 is shown in FIG. The heat insulating sheet 10 shown in this figure is composed of an intermediate layer 11 and a surface layer 12 laminated on both sides so as to sandwich the intermediate layer 11.
　これら中間層１１と表面層１２とで、熱伝導率を異ならせている。具体的には、表面層１２の厚さ方向の熱伝導率を、０．５０Ｗ／ｍ・Ｋ以下とし、中間層１１の厚さ方向の熱伝導率を１．００Ｗ／ｍ・Ｋ以上としている。このように絶縁シートを、各表面層１２を熱伝導率を抑えた断熱層としつつ、間に介在される中間層１１を熱伝導性を高めた放熱層とした多層構造とすることで、表面層１２が薄くとも断熱性能に優れた断熱シート１０を実現できる。 The thermal conductivity is different between the intermediate layer 11 and the surface layer 12. Specifically, the thermal conductivity in the thickness direction of the surface layer 12 is 0.50 W / m · K or less, and the thermal conductivity in the thickness direction of the intermediate layer 11 is 1.00 W / m · K or more. .. In this way, the insulating sheet has a multi-layered structure in which each surface layer 12 is a heat insulating layer having suppressed thermal conductivity, and the intermediate layer 11 interposed between them is a heat radiating layer having improved thermal conductivity. Even if the layer 12 is thin, the heat insulating sheet 10 having excellent heat insulating performance can be realized.
　また中間層１１の面方向の熱伝導率は、厚さ方向の５倍以上としている。これにより、断熱性能の高い表面層１２と組み合わせた断熱シート１０の断熱性能を発揮させながら、ホットスポットの発生を効果的に解消しつつ、類焼防止を図ることが可能となる。 The thermal conductivity of the intermediate layer 11 in the plane direction is 5 times or more in the thickness direction. As a result, it is possible to prevent burning while effectively eliminating the generation of hot spots while demonstrating the heat insulating performance of the heat insulating sheet 10 combined with the surface layer 12 having high heat insulating performance.
　従来の断熱シートでは、類焼防止の観点から断熱性能の高い、換言すると熱伝導率の低い材質で構成されていた。この結果、図４の模式断面図に示すように、二次電池セル１の一部が局所的に高温になるホットスポットＨＳが発生しても、この高熱を断熱シート１０Ｘで熱伝導して放熱することができなかった。この結果、熱の逃げ場のないホットスポットＨＳが益々高温となって、ついには燃焼して熱暴走する可能性があった。しかしながら断熱シートの熱伝導率を上げると、断熱性能を発揮できなくなって隣接する二次電池セルに高温が伝搬してしまい、類焼の発生を抑制できず、断熱シートの本来の機能を発揮できないという矛盾があった。 The conventional heat insulating sheet was made of a material with high heat insulating performance, in other words, low thermal conductivity, from the viewpoint of preventing burning. As a result, as shown in the schematic cross-sectional view of FIG. 4, even if a hot spot HS in which a part of the secondary battery cell 1 becomes locally hot is generated, this high heat is thermally conducted by the heat insulating sheet 10X to dissipate heat. Couldn't. As a result, the hot spot HS, which has no heat escape, becomes hotter and hot, and there is a possibility that it will eventually burn and run away from heat. However, if the thermal conductivity of the heat insulating sheet is increased, the heat insulating performance cannot be exhibited and the high temperature propagates to the adjacent secondary battery cells, the occurrence of burning cannot be suppressed, and the original function of the heat insulating sheet cannot be exhibited. There was a contradiction.
　これに対し本実施形態に係る断熱シート１０では、表面層１２を熱伝導率を抑えた断熱層として、二次電池セル１に対向させている。これによって隣接する二次電池セル１間に介在された断熱シート１０は、左右の二次電池セルを高い断熱性によって断熱できる。また、表面層１２を絶縁層とすることで、二次電池セル同士の意図しない短絡を回避できる。特に外装缶を金属製とする二次電池セルを用いる場合に、二次電池セル間の絶縁性を高めて安全性、信頼性の向上に寄与できる。 On the other hand, in the heat insulating sheet 10 according to the present embodiment, the surface layer 12 is opposed to the secondary battery cell 1 as a heat insulating layer having suppressed thermal conductivity. As a result, the heat insulating sheet 10 interposed between the adjacent secondary battery cells 1 can insulate the left and right secondary battery cells with high heat insulating properties. Further, by using the surface layer 12 as an insulating layer, it is possible to avoid an unintended short circuit between the secondary battery cells. In particular, when a secondary battery cell whose outer can is made of metal is used, it is possible to improve the insulation between the secondary battery cells and contribute to the improvement of safety and reliability.
　一方で、図５の模式断面図に示すように、いずれかの二次電池セルで万一、局所的に高温になるホットスポットＨＳが発生しても、この二次電池セルと面した表面層１２（図５において右側）で断熱性を発揮させつつも、中間層１１に達した熱については、面方向に積極的に熱伝導させることで、熱が表面層１２の全面に伝搬されて拡散される結果、高温の発生箇所から熱を奪うことでホットスポットの拡大を抑制できる。特に、中間層１１の面方向の熱伝導率を、厚さ方向の５倍以上とすることで、面方向への熱伝導が促進され、背面側への熱伝導を抑制して、背面側に位置する二次電池セルに高熱が伝わる事態を防ぎつつも、面方向に積極的に熱伝搬させて、類焼を抑える効果を発揮できる。さらに図１に示すように断熱シート１０の端面を側板２と熱結合したり、あるいは放熱部材に熱結合することで、さらに放熱性を高めることができ、二次電池セルから吸熱して熱暴走を抑制できる。 On the other hand, as shown in the schematic cross-sectional view of FIG. 5, even if a hot spot HS that becomes locally hot occurs in any of the secondary battery cells, the surface layer facing the secondary battery cell. 12 (on the right side in FIG. 5) exhibits heat insulating properties, but the heat that has reached the intermediate layer 11 is positively conducted in the plane direction, so that the heat is propagated and diffused over the entire surface of the surface layer 12. As a result, the expansion of the hot spot can be suppressed by removing heat from the place where the high temperature is generated. In particular, by setting the thermal conductivity of the intermediate layer 11 in the surface direction to 5 times or more the thickness direction, the heat conduction in the surface direction is promoted, the heat conduction to the back surface side is suppressed, and the heat conduction to the back surface side is suppressed. While preventing the situation where high heat is transferred to the located secondary battery cell, it can exert the effect of suppressing burning by positively propagating heat in the plane direction. Further, as shown in FIG. 1, the end face of the heat insulating sheet 10 is thermally coupled to the side plate 2 or thermally coupled to the heat radiating member to further improve the heat radiating property, and heat is absorbed from the secondary battery cell to cause thermal runaway. Can be suppressed.
　その一方で、裏面側の表面層１２（図５において左側）の断熱効果によって、他の二次電池セルに高熱が伝搬することを阻止乃至抑制して、類焼のリスクを低減できる。このように、断熱シート１０を多層構造として、中間層１１に熱拡散機能を付加してホットスポットＨＳを抑制する一方、表面層１２には断熱機能を付加して他の二次電池セルへの類焼を防止することで、従来実現困難であった、放熱性能と断熱性能という相反する機能を両立させて、安全性を高めている。
（表面層１２） On the other hand, the heat insulating effect of the surface layer 12 on the back surface side (left side in FIG. 5) can prevent or suppress the propagation of high heat to other secondary battery cells, and can reduce the risk of burning. In this way, the heat insulating sheet 10 has a multi-layer structure, and a heat diffusion function is added to the intermediate layer 11 to suppress hot spot HS, while a heat insulating function is added to the surface layer 12 to the other secondary battery cells. By preventing burning, it enhances safety by achieving both the contradictory functions of heat dissipation performance and heat insulation performance, which were difficult to achieve in the past.
(Surface layer 12)
　表面層１２は、厚さ方向の熱伝導率を０．５０Ｗ／ｍ・Ｋ以下、より好ましくは０．０１Ｗ／ｍ・Ｋ～０．３０Ｗ／ｍ・Ｋ、さらに好ましくは０．０２Ｗ／ｍ・Ｋ～０．２０Ｗ／ｍ・Ｋとする。このような表面層１２は、十分な断熱性能を発揮させるため、繊維、充填材、バインダのいずれかを含むことが好ましい。 The surface layer 12 has a thermal conductivity of 0.50 W / m · K or less in the thickness direction, more preferably 0.01 W / m · K to 0.30 W / m · K, still more preferably 0.02 W / m · K. It is set to K to 0.20 W / m · K. Such a surface layer 12 preferably contains any of fibers, fillers, and binders in order to exhibit sufficient heat insulating performance.
　また表面層１２の細孔径は、５０μｍ以下とすることが好ましく、３０μｍ以下がより好ましく、２０μｍ以下がさらに好ましい。これにより、断熱シートの粉落ちを抑制して、表面層を封止する等の粉落ち防止のための処理を不要とできる。 The pore diameter of the surface layer 12 is preferably 50 μm or less, more preferably 30 μm or less, and even more preferably 20 μm or less. As a result, it is possible to suppress the powder falling of the heat insulating sheet and eliminate the need for a treatment for preventing the powder falling such as sealing the surface layer.
　また表面層１２の透気抵抗度は、ＪＩＳ　Ｐ　８１１７（２００９）試験に準拠したガーレー標準形デンソメータで３～５０００ｓｅｃ／１００ｍｌとすることが好ましく、５～１０００ｓｅｃ／１００ｍｌとすることがさらに好ましい。透気抵抗度がこの範囲より小さいと、後述する中間層から繊維又は粉末が脱落した際、その散乱を防止できず、短絡を引き起こす可能性がある。また透気抵抗度がこの範囲より大きいと、後述する接着層との接着強度が低下し易くなる。 The air permeability resistance of the surface layer 12 is preferably 3 to 5000 sec / 100 ml, more preferably 5 to 1000 sec / 100 ml, using a Garley standard densometer conforming to the JIS P 8117 (2009) test. If the air permeation resistance is smaller than this range, when the fiber or powder falls off from the intermediate layer described later, its scattering cannot be prevented and a short circuit may occur. Further, when the air permeation resistance is larger than this range, the adhesive strength with the adhesive layer described later tends to decrease.
　また表面層１２の平滑度は、ＪＩＳ　Ｐ　８１１９（１９９８）に準拠した平滑度試験機で、真空容器内の圧力が５０．７ｋＰａから２９．３ｋＰａに変化するまでの時間が１５～１５０ｓｅｃとすることが好ましい。 The smoothness of the surface layer 12 is a smoothness tester based on JIS P 8119 (1998), and the time until the pressure in the vacuum vessel changes from 50.7 kPa to 29.3 kPa is 15 to 150 sec. Is preferable.
　さらに表面層１２は、１００ｋＰａで圧縮した時の圧縮率が１０%以上としている。これにより、二次電池セルの膨張時又は振動が与えられた時、中間層１１への応力を緩和して、絶縁を阻害する繊維又は粉末の脱落を抑制できる。 Further, the surface layer 12 has a compression rate of 10% or more when compressed at 100 kPa. As a result, when the secondary battery cell expands or is subjected to vibration, the stress on the intermediate layer 11 can be relaxed and the fiber or powder that inhibits insulation can be suppressed from falling off.
　ここでは、断熱シート１０の表面層１２は、繊維基材と、充填材と、結合材を含む。好適には、繊維基材として天然パルプと無機繊維、充填材として珪酸塩鉱物、結合材としてゴム組成物を利用できる。具体的には、実施形態１に係る表面層１２は、繊維基材として麻パルプとマイクロガラス、充填材としてタルクとセピオライト、結合材としてＮＢＲを含んでいる。 Here, the surface layer 12 of the heat insulating sheet 10 includes a fiber base material, a filler, and a binder. Preferably, natural pulp and inorganic fibers can be used as the fiber base material, silicate minerals can be used as the filler, and rubber compositions can be used as the binder. Specifically, the surface layer 12 according to the first embodiment contains hemp pulp and microglass as a fiber base material, talc and sepiolite as a filler, and NBR as a binder.
　繊維基材（基材繊維とも呼ぶ。）は、ガラス繊維、カーボン繊維、セラミック繊維などの無機繊維や、あるいは芳香族ポリアミド繊維、ポリエチレン繊維などの有機繊維が利用できる。ここでは、繊維基材として有機繊維の天然パルプを用いている。天然パルプには麻パルプが好適に利用できる。麻パルプの配合比率は、例えば５重量％～２０重量％、好ましくは１０重量％とする。 As the fiber base material (also called base fiber), inorganic fibers such as glass fibers, carbon fibers and ceramic fibers, or organic fibers such as aromatic polyamide fibers and polyethylene fibers can be used. Here, natural pulp of organic fiber is used as the fiber base material. Hemp pulp can be preferably used as natural pulp. The blending ratio of hemp pulp is, for example, 5% by weight to 20% by weight, preferably 10% by weight.
　また繊維基材として、無機繊維を含めてもよい。無機繊維の配合比率は、５重量％～２０重量％、好ましくは８重量％～１５重量％とする。実施形態１においては、無機繊維としてマイクロガラスを１２重量％添加している。 Inorganic fibers may also be included as the fiber base material. The blending ratio of the inorganic fibers is 5% by weight to 20% by weight, preferably 8% by weight to 15% by weight. In the first embodiment, 12% by weight of microglass is added as an inorganic fiber.
　充填材は、無機の充填材が利用できる。無機充填材としては、セピオライト、タルク、カオリン、マイカ、セリサイト等の珪酸塩鉱物、炭酸マグネシウム、炭酸カルシウム、ハードクレー、焼成クレー、硫酸バリウム、珪酸カルシウム、ウォラストナイト、重炭酸ナトリウム、ホワイトカーボン・溶融シリカ等の合成シリカ、珪藻土等の天然シリカ、水酸化アルミニウム、水酸化マグネシウム、ガラスビーズ等が挙げられ、これらは単独又は複数を組み合わせて用いられる。これらの無機充填材の添加は、高温雰囲気下の形状維持と断熱性向上といった効果を示す。実施形態１においては、可撓性が高いタルクを用いた。充填材の配合量は断熱シート中、５重量％～６５重量％が好ましい。実施形態１においては、充填材として珪酸マグネシウムを用い、タルクを５８重量％、セピオライトを１４重量％添加している。 Inorganic filler can be used as the filler. Inorganic fillers include silicate minerals such as sepiolite, talc, kaolin, mica, and sericite, magnesium carbonate, calcium carbonate, hard clay, calcined clay, barium sulfate, calcium silicate, wollastonite, sodium bicarbonate, and white carbon. -Synthetic silica such as molten silica, natural silica such as silicate soil, aluminum hydroxide, magnesium hydroxide, glass beads and the like can be mentioned, and these may be used alone or in combination of two or more. The addition of these inorganic fillers has the effects of maintaining the shape and improving the heat insulating property in a high temperature atmosphere. In the first embodiment, talc having high flexibility was used. The blending amount of the filler is preferably 5% by weight to 65% by weight in the heat insulating sheet. In the first embodiment, magnesium silicate is used as a filler, and 58% by weight of talc and 14% by weight of sepiolite are added.
　結合材には、塩化ビニル樹脂、塩化ビニリデン樹脂、アクリル酸樹脂、ウレタン樹脂、酢酸ビニル樹脂、ポリエチレン樹脂、ポリスチレン樹脂、アクリロブタジエンスチレン樹脂、アクリロニトリルスチレン樹脂、フッ素樹脂、シリコーン樹脂、エポキシ樹脂、フェノール樹脂等の合成樹脂の他に、アクリルニトリルブタジエンゴム、水素化アクリルニトリルブタジエンゴム、アクリルゴム、アクリルニトリルゴム、エチレンプロピレンゴム、スチレンブタジエンゴム、クロロプレーンゴム、ブタジエンゴム、ブチルゴム、フッ素ゴム、シリコーンゴム、フッ化シリコーンゴム、クロロスルフォン化ゴム、エチレン酢ビゴム、塩化ポリエチレン、塩化ブチルゴム、エピクロルヒドリンゴム、ニトリルイソプレンゴム、天然ゴム、イソプレンゴム等が利用できる。中でも、アクリルニトリルブタジエンゴム（ＮＢＲ）が、耐水性、耐油性が高い点で好ましい。これらのゴムは１種又は２種以上を組み合わせて使用することができる。また、より高い耐水性、耐油性を目的にアルキルケテンダイマー等のサイズ剤やフッ素系、シリコーン系の撥水剤を組合わせて使用することもできる。結合材にゴム組成物を用いる場合、ゴムの配合量は断熱シート中、５．０～４０重量％が好ましい。ここではＮＢＲであるニポール１５６２を６．０重量％添加している。 The binder includes vinyl chloride resin, vinylidene chloride resin, acrylic acid resin, urethane resin, vinyl acetate resin, polyethylene resin, polystyrene resin, acrylobutadiene styrene resin, acrylonitrile styrene resin, fluororesin, silicone resin, epoxy resin, and phenol. In addition to synthetic resins such as resins, acrylic nitrile butadiene rubber, hydride acrylic nitrile butadiene rubber, acrylic rubber, acrylic nitrile rubber, ethylene propylene rubber, styrene butadiene rubber, chloroplane rubber, butadiene rubber, butyl rubber, fluororubber, silicone rubber , Fluorosilicone rubber, chlorosulphonized rubber, ethylene vinegar rubber, polyethylene chloride, butyl chloride rubber, epichlorohydrin rubber, nitrile isoprene rubber, natural rubber, isoprene rubber and the like can be used. Of these, acrylic nitrile butadiene rubber (NBR) is preferable because it has high water resistance and oil resistance. These rubbers can be used alone or in combination of two or more. Further, for the purpose of higher water resistance and oil resistance, a sizing agent such as an alkyl ketene dimer and a fluorine-based or silicone-based water repellent can be used in combination. When a rubber composition is used as the binder, the amount of rubber to be blended is preferably 5.0 to 40% by weight in the heat insulating sheet. Here, 6.0% by weight of NBR Nipol 1562 is added.
　さらに添加剤として、紙力剤や定着剤、消泡剤等の薬品類を加えている。ここでは紙力剤としてＷＳ４０３０を０．５重量％、紙力剤としてコーガム１５Ｈを０．３重量％、定着剤として硫酸バンドを１．９重量％、消泡剤としてＫＭ－７０を適量添加している。 Furthermore, as additives, chemicals such as paper strength agents, fixing agents, and antifoaming agents are added. Here, 0.5% by weight of WS4030 was added as a paper strength agent, 0.3% by weight of cogham 15H was added as a paper strength agent, 1.9% by weight of a sulfate band was added as a fixing agent, and an appropriate amount of KM-70 was added as an antifoaming agent. ing.
　表面層１２は、厚さを１ｍｍ～５．５ｍｍ、好ましくは０．１５ｍｍ～２ｍｍ、より好ましくは０．２ｍｍ～１ｍｍとする。この表面層１２は、一層で構成する他、層状に構成したガラス繊維層やセラミック繊維層等の無機繊維層を複数層積層して構成してもよい。また無機繊維は、繊維長１３ｍｍ以上のものが圧縮復元性の観点から好適に使用できる。より好ましくは４０ｍｍ以上、さらに好ましくは、切断されていない長繊維のものである。
（中間層１１） The surface layer 12 has a thickness of 1 mm to 5.5 mm, preferably 0.15 mm to 2 mm, and more preferably 0.2 mm to 1 mm. In addition to being composed of one layer, the surface layer 12 may be composed of a plurality of layers of inorganic fiber layers such as a layered glass fiber layer and a ceramic fiber layer. Further, as the inorganic fiber, a fiber having a fiber length of 13 mm or more can be preferably used from the viewpoint of compressive stability. It is more preferably 40 mm or more, and even more preferably uncut long fiber.
(Middle layer 11)
　中間層１１は、厚さ方向の熱伝導率を１．００Ｗ／ｍ・Ｋ以上、好ましくは２．００Ｗ／ｍ・Ｋ～２０．００Ｗ／ｍ・Ｋ、より好ましくは２．５０Ｗ／ｍ・Ｋ～１５．００Ｗ／ｍ・Ｋとする。あるいは中間層１１の厚さ方向の熱伝導率を、３．００Ｗ／ｍ・Ｋ以下としてもよい。また中間層１１の面方向の熱伝導率は、１０００Ｗ／ｍ・Ｋ以下とすることが好ましい。この構成により、電源装置１００に防爆弁等のガス排出装置が設けられている場合、いずれかの二次電池セル１が熱暴走する過程で、外装缶を通じて別の二次電池セルへ高熱が伝播する前に、電解液の熱分解ガスが排出されて電源装置１００が冷却される時間的な猶予を確保することができる。 The intermediate layer 11 has a thermal conductivity of 1.00 W / m · K or more in the thickness direction, preferably 2.00 W / m · K to 20.00 W / m · K, and more preferably 2.50 W / m · K. It is set to ~ 15.00 W / m · K. Alternatively, the thermal conductivity of the intermediate layer 11 in the thickness direction may be 3.00 W / m · K or less. The thermal conductivity of the intermediate layer 11 in the plane direction is preferably 1000 W / m · K or less. With this configuration, when the power supply device 100 is provided with a gas discharge device such as an explosion-proof valve, high heat propagates to another secondary battery cell through the outer can in the process of thermal runaway of any of the secondary battery cells 1. It is possible to secure a time grace period for the thermal decomposition gas of the electrolytic solution to be discharged and the power supply device 100 to be cooled before the operation.
　このような中間層１１は、十分な熱伝導性を発揮させるため、有機繊維や熱伝導フィラーを含むことが好ましい。有機繊維は、パラアラミド繊維、パラアラミドパルプ、メタアラミドパルプ、ポリフェニレンサルファイド繊維、ＰＥＴ繊維、、難燃ＰＥＴ繊維、難燃レーヨン繊維のいずれか一以上を利用できる。また熱伝導フィラーには、酸化マグネシウム、酸化アルミニウム、窒化硼素、、窒化アルミニウム、アルミニウム、銅、黒鉛、カーボンナノチューブ等が利用できる。また中間層１１に、無機繊維を含めてもよい。無機繊維には、カーボン繊維、ガラス繊維、セラミック繊維等が利用できる。また抄紙シートで構成した中間シートは、熱カレンダーロール等による、加圧加工を行ってもよい。これにより内部を緻密化して、熱伝導率を高めることができる。 It is preferable that such an intermediate layer 11 contains an organic fiber or a heat conductive filler in order to exhibit sufficient heat conductivity. As the organic fiber, any one or more of para-aramid fiber, para-aramid pulp, meta-aramid pulp, polyphenylene sulfide fiber, PET fiber, flame-retardant PET fiber, and flame-retardant rayon fiber can be used. Further, as the heat conductive filler, magnesium oxide, aluminum oxide, boron nitride, aluminum nitride, aluminum, copper, graphite, carbon nanotubes and the like can be used. Further, the intermediate layer 11 may contain inorganic fibers. As the inorganic fiber, carbon fiber, glass fiber, ceramic fiber and the like can be used. Further, the intermediate sheet composed of the papermaking sheet may be pressure-processed by a thermal calender roll or the like. As a result, the inside can be densified and the thermal conductivity can be increased.
　また中間層１１は、鉄、アルミニウム、銅、銀、金等の膜状の金属が利用できる。 Further, as the intermediate layer 11, a film-like metal such as iron, aluminum, copper, silver, and gold can be used.
　中間層１１は、厚さを０．０２ｍｍ～０．５ｍｍ、好ましくは０．０３ｍｍ～０．４ｍｍ、より好ましくは０．０３ｍｍ～０．３ｍｍとする。 The thickness of the intermediate layer 11 is 0.02 mm to 0.5 mm, preferably 0.03 mm to 0.4 mm, and more preferably 0.03 mm to 0.3 mm.
　また中間層１１も、透気抵抗度をＪＩＳ　Ｐ　８１１７（２００９）試験に準拠したガーレー標準型デンソメータで３０００ｓｅｃ／ｍｌ以上とすることが好ましい。これにより、粉落ちの少ない熱拡散性を有する中間層１１を実現しており、熱拡散性を有する層の封止を不要として製造を容易にかつ安価に行える利点が得られている。
（接着層） Further, it is preferable that the air permeability resistance of the intermediate layer 11 is 3000 sec / ml or more with a Garley standard type densometer conforming to the JIS P 8117 (2009) test. As a result, the intermediate layer 11 having heat diffusivity with less powder falling is realized, and there is an advantage that the production can be easily and inexpensively performed without the need for sealing the layer having heat diffusivity.
(Adhesive layer)
　中間層１１と表面層１２とは、接着材で接着される。接着材を硬化させた接着層が、中間層１１と表面層１２との間に介在される。接着材は、耐熱性に優れた材質が好ましい。このような接着材としては、アクリル系接着材、塩化ビニル系接着材、酢酸ビニル系接着材、ホットメルト等が利用できる。接着剤の形態は液状、スラリー状のほか、ホットメルト接着剤を不織布又は網状に成型した熱融着シート等が利用できる。 The intermediate layer 11 and the surface layer 12 are adhered with an adhesive. An adhesive layer obtained by curing the adhesive is interposed between the intermediate layer 11 and the surface layer 12. The adhesive material is preferably a material having excellent heat resistance. As such an adhesive, an acrylic adhesive, a vinyl chloride adhesive, a vinyl acetate adhesive, a hot melt, or the like can be used. The form of the adhesive can be liquid, slurry, or a heat-sealed sheet obtained by molding a hot melt adhesive into a non-woven fabric or a net.
　また断熱シート１０の全体の厚さは、０．２ｍｍ～６．０ｍｍ、好ましくは０．２ｍｍ～４．０ｍｍ、より好ましくは０．３ｍｍ～２．０ｍｍとする。 The overall thickness of the heat insulating sheet 10 is 0.2 mm to 6.0 mm, preferably 0.2 mm to 4.0 mm, and more preferably 0.3 mm to 2.0 mm.
　さらに断熱シート１０は、柔軟性、可撓性を備えている。これによって、図５の断面図に示すように二次電池セル１が膨張した際、このような二次電池セル１の変形に追従して、密着状態を維持し、空隙の形成によって熱伝導性が低下する事態を回避できる。特に従来の断熱シートは、硬質のものが多く、変形に対する追従性が低いため、接触面に空隙が形成されて空気層による断熱効果のため、熱伝導性が低下することがあった。断熱シートが類焼防止のため断熱性能を発揮させることを目的としている場合は、空気層によって断熱性能が一層向上するため、硬質の断熱シートは却って好都合であった。これに対し本実施形態に係る断熱シート１０のように、表面層１２は放熱性能を発揮させるためには、このような硬質材よりも、可撓性や柔軟性を有する断熱シート１０とすることで、熱伝導率の高い状態を維持して放熱性能を発揮させることができる。 Further, the heat insulating sheet 10 has flexibility and flexibility. As a result, when the secondary battery cell 1 expands as shown in the cross-sectional view of FIG. 5, it follows the deformation of the secondary battery cell 1 and maintains a close contact state, and is thermally conductive due to the formation of voids. Can be avoided. In particular, many of the conventional heat insulating sheets are hard and have low followability to deformation. Therefore, voids are formed on the contact surface and the heat insulating effect of the air layer may reduce the thermal conductivity. When the heat insulating sheet is intended to exhibit heat insulating performance in order to prevent burning, a hard heat insulating sheet is rather convenient because the heat insulating performance is further improved by the air layer. On the other hand, like the heat insulating sheet 10 according to the present embodiment, the surface layer 12 should be a heat insulating sheet 10 having flexibility and flexibility rather than such a hard material in order to exhibit heat dissipation performance. Therefore, it is possible to maintain a high thermal conductivity and exhibit heat dissipation performance.
　また断熱シート１０に柔軟性、可撓性を持たせることで、ロール材などの巻取材に巻取可能となり、ロール状での保管、運搬が可能となって、ハンドリング性も向上される。ここでは可撓性を発揮させるため、例えば断熱シート１０の片面に外径１１０ｍｍの円筒を当てて９０°折り曲げた際、皺又は割れが生じないこととすることができる。 Further, by giving the heat insulating sheet 10 flexibility and flexibility, it becomes possible to wind it on a winding material such as a roll material, it becomes possible to store and transport it in a roll shape, and the handling property is improved. Here, in order to exhibit flexibility, for example, when a cylinder having an outer diameter of 110 mm is applied to one side of the heat insulating sheet 10 and bent by 90 °, wrinkles or cracks can be prevented.
　さらに断熱シート１０は、耐熱性や難燃性を備えることが望ましい。二次電池セル１が高温になっても、変形や溶融し難い材質とすることで、断熱性能を維持することが可能となる。好ましくは、断熱シート１０の耐熱温度を３００～６００℃とする。本実施形態に係る断熱シートでは、表面層を、繊維と充填材と結合材（バインダ）で構成することにより高い耐熱温度を発揮でき、高温環境下でも絶縁性を維持できる。さらに、ＪＩＳ　Ｌ　１０９１　Ａ－１法（１９９９）試験に準じて１０分間加熱した際における裏面の灰化面積を、５００ｍｍ2以下に抑えることが好ましい。 Further, it is desirable that the heat insulating sheet 10 has heat resistance and flame retardancy. Even if the secondary battery cell 1 becomes hot, the heat insulating performance can be maintained by using a material that is not easily deformed or melted. Preferably, the heat resistant temperature of the heat insulating sheet 10 is 300 to 600 ° C. In the heat insulating sheet according to the present embodiment, by forming the surface layer with fibers, a filler, and a binder, a high heat resistant temperature can be exhibited, and the insulating property can be maintained even in a high temperature environment. Further, it is preferable to suppress the ashed area on the back surface to 500 mm 2 or less when heated for 10 minutes according to the JIS L 1091 A-1 method (1999) test.
　加えて、本実施形態に係る断熱シート１０においては、断熱シート全体での平滑度を、１５～１５０ｓｅｃとすることが好ましい。これにより、断熱シートの封止を不要として製造を容易にかつ安価に行える利点が得られる。 In addition, in the heat insulating sheet 10 according to the present embodiment, it is preferable that the smoothness of the entire heat insulating sheet is 15 to 150 sec. This has the advantage that the heat insulating sheet does not need to be sealed and can be manufactured easily and inexpensively.
　また本実施形態に係る断熱シートは、変形可能な柔軟性を備えることができる。好適には、曲率半径５５ｍｍの紙管に巻き付けても破断しない柔軟性を備える。これにより、断熱シートを接触させる対象物が膨張する等変形しても、その変形に追従して密着状態を維持でき、空隙が形成されて熱伝導性が低下する事態を回避できる。
（断熱シート１０の製造法） Further, the heat insulating sheet according to the present embodiment can be provided with deformable flexibility. Preferably, it has a flexibility that does not break even when wound around a paper tube having a radius of curvature of 55 mm. As a result, even if the object with which the heat insulating sheet is in contact is deformed, such as by expanding, it is possible to maintain the close contact state by following the deformation, and it is possible to avoid the situation where voids are formed and the thermal conductivity is lowered.
(Manufacturing method of heat insulating sheet 10)
　ここで断熱シート１０は、例えばロール状とした中間層１１及び表面層１２の間に、熱融着シートを挟み込み、２本の熱圧着ロールの間を通過させ接着することで、ロールｔｏロールの製造が可能である。また、中間層１１ないし表面層１２の片面あるいは両面に液状の接着剤を塗工し、貼り合わせてもよい。後述する実施例１～４及び比較例１～２では、中間層１１と表面層１２の間にポリエチレン製熱融着シートを挟み、１５０℃のホットプレスで、５０ｋＰａにて２０秒間加圧し接着させた。 Here, the heat insulating sheet 10 is a roll-to-roll by sandwiching a heat-sealing sheet between, for example, a roll-shaped intermediate layer 11 and a surface layer 12, passing between two thermocompression bonding rolls, and adhering them. It can be manufactured. Further, a liquid adhesive may be applied to one or both sides of the intermediate layer 11 to the surface layer 12 and bonded to each other. In Examples 1 to 4 and Comparative Examples 1 and 2, which will be described later, a polyethylene heat-sealing sheet is sandwiched between the intermediate layer 11 and the surface layer 12, and is pressed and bonded at 50 kPa for 20 seconds with a hot press at 150 ° C. rice field.
　以上の例では、断熱シート１０を、中間層１１の両面をそれぞれ単層の表面層１２で被覆した三層構造とする構成を説明した。ただ本発明は、このような三層構造に限定するものでなく、例えば表面層を複数層としたり、中間層を複数層とするなど、四層以上の多層構造とすることもできる。あるいは、用途によっては中間層の片面のみに表面層を設けた二層構造としても良い。 In the above example, the configuration in which the heat insulating sheet 10 has a three-layer structure in which both sides of the intermediate layer 11 are covered with a single surface layer 12 has been described. However, the present invention is not limited to such a three-layer structure, and may be a multi-layer structure having four or more layers, for example, a surface layer having a plurality of layers or an intermediate layer having a plurality of layers. Alternatively, depending on the application, a two-layer structure in which a surface layer is provided on only one side of the intermediate layer may be used.
　また図１の例では、二次電池セル１を縦置きの姿勢としているが、二次電池セルを横置きの姿勢とする電源装置においても、断熱シートを同様に適用できることはいうまでもない。 Further, in the example of FIG. 1, the secondary battery cell 1 is placed in a vertical position, but it goes without saying that the heat insulating sheet can be similarly applied to a power supply device in which the secondary battery cell is placed in a horizontal position.
　さらに断熱シート１０は、二次電池セル間の断熱のみならず、複数の二次電池セルで構成された電池モジュール同士の間の断熱に利用することもできる。
［実施例１～４；比較例１］ Further, the heat insulating sheet 10 can be used not only for heat insulation between secondary battery cells but also for heat insulation between battery modules composed of a plurality of secondary battery cells.
[Examples 1 to 4; Comparative Example 1]
　ここで、実施例に係る断熱シートの難燃性を確認すべく、実施例１～４に係る断熱シートのサンプルを作製し、比較例１に係る断熱シートのサンプルと比較した。各サンプルに用いた中間層と表面層の厚さと熱伝導率を表１に示す。 Here, in order to confirm the flame retardancy of the heat insulating sheet according to the example, a sample of the heat insulating sheet according to Examples 1 to 4 was prepared and compared with the sample of the heat insulating sheet according to Comparative Example 1. Table 1 shows the thickness and thermal conductivity of the intermediate layer and surface layer used for each sample.
　実施例１～４及び比較例１において、表面層は天然パルプ、マイクロガラス、珪酸塩鉱物粉体と、結合剤としてゴム系樹脂を抄紙した同一のシートを使用した。その作成には、まず離解させた天然パルプを準備し、マイクロガラスと珪酸塩鉱物粉体とを均一に分散させた。これにゴム系樹脂を加えて得られた抄紙スラリーを、湿式抄紙法で抄紙して、厚さ約０．７０ｍｍの表面層基材シートを得た。この表面層基材シートの熱伝導率（厚さ方向）は０．１８Ｗ／ｍ・Ｋ、熱伝導率（面方向）は０．１８Ｗ／ｍ・Ｋ、平滑度は４６．８ｓｅｃ、透気抵抗度は３０ｓｅｃ／１００ｍｌであった。この表面層基材シートを用いて、異なる中間層の両面を被覆して、実施例１～４及び比較例１を作製した。
（実施例１） In Examples 1 to 4 and Comparative Example 1, the same sheet made of natural pulp, microglass, silicate mineral powder and a rubber-based resin as a binder was used as the surface layer. To prepare the pulp, first, the dissociated natural pulp was prepared, and the microglass and the silicate mineral powder were uniformly dispersed. The papermaking slurry obtained by adding a rubber-based resin to this was made by a wet papermaking method to obtain a surface layer base material sheet having a thickness of about 0.70 mm. The thermal conductivity (thickness direction) of this surface layer base material sheet is 0.18 W / m · K, the thermal conductivity (plane direction) is 0.18 W / m · K, the smoothness is 46.8 sec, and the air permeability resistance. The degree was 30 sec / 100 ml. Using this surface layer base material sheet, both sides of different intermediate layers were covered to prepare Examples 1 to 4 and Comparative Example 1.
(Example 1)
　実施例１の中間層として、黒鉛紛９０％の抄紙シートを使用した。具体的には黒鉛紛及び有機繊維を、重量比９０対１０となるよう水中に分散させた抄紙用スラリーを準備し、湿式抄紙法により得られたシートに熱圧加工を行い、中間層基材シートを得た。その厚さは０．２３ｍｍであった。 A papermaking sheet containing 90% graphite powder was used as the intermediate layer of Example 1. Specifically, a papermaking slurry in which graphite powder and organic fibers are dispersed in water so as to have a weight ratio of 90:10 is prepared, and the sheet obtained by the wet papermaking method is subjected to thermal pressure processing to obtain an intermediate layer base material. I got a sheet. Its thickness was 0.23 mm.
　得られた中間層基材シートの両面に表面層をそれぞれ積層し、さらに表面層と中間層の間にポリエチレン製熱融着シートを挟み、１５０℃のホットプレスにて、２０秒間５０ｋＰａで加圧を行い貼り合せ、実施例１に係る断熱シートを得た。
（実施例２） A surface layer is laminated on both sides of the obtained intermediate layer base material sheet, a polyethylene heat-sealing sheet is sandwiched between the surface layer and the intermediate layer, and a pressure is applied at 50 kPa for 20 seconds by a hot press at 150 ° C. The heat insulating sheet according to Example 1 was obtained.
(Example 2)
　実施例２の中間層として、黒鉛紛及び有機繊維を、重量比７５対２５となるよう水中に分散させた抄紙用スラリーを準備し、湿式抄紙法により得られたシートに熱圧加工を行い、表面層基材シート２を得た。その厚さは０．０７ｍｍであった。得られた中間層基材シートに対し、実施例１と同様に両面にそれぞれ表面層を貼り合せて、実施例２に係る断熱シートを得た。
（実施例３） As the intermediate layer of Example 2, a papermaking slurry in which graphite powder and organic fibers were dispersed in water so as to have a weight ratio of 75:25 was prepared, and the sheet obtained by the wet papermaking method was subjected to thermal pressure processing. A surface layer base material sheet 2 was obtained. Its thickness was 0.07 mm. A surface layer was laminated on both sides of the obtained intermediate layer base material sheet in the same manner as in Example 1 to obtain a heat insulating sheet according to Example 2.
(Example 3)
　実施例３の中間層は、アルミニウム膜とした。ここでは、厚さ０．２ｍｍの、岩田製作所製シムプレートアルミＴＡ２００－３００－０２を用いて中間層基材シートとした。この中間層基材シートを、実施例１等と同様に表面層を各面に貼り合せて、実施例３に係る断熱シートを得た。
（実施例４） The intermediate layer of Example 3 was an aluminum film. Here, a shim plate aluminum TA200-300-02 manufactured by Iwata Seisakusho with a thickness of 0.2 mm was used as an intermediate layer base material sheet. The surface layer of this intermediate layer base material sheet was bonded to each surface in the same manner as in Example 1 and the like to obtain a heat insulating sheet according to Example 3.
(Example 4)
　実施例４の中間層として、薄手のアルミニウム膜を用いた。ここでは、厚さ０．１ｍｍの、岩田製作所製シムプレートアルミＴＡ２００－３００－０１を用いて中間層基材シートとした。この中間層基材シートを、実施例１等と同様に表面層を各面に貼り合せて、実施例４に係る断熱シートを得た。
（比較例１） A thin aluminum film was used as the intermediate layer of Example 4. Here, a shim plate aluminum TA200-300-01 manufactured by Iwata Seisakusho with a thickness of 0.1 mm was used as an intermediate layer base material sheet. The surface layer of this intermediate layer base material sheet was bonded to each surface in the same manner as in Example 1 and the like to obtain a heat insulating sheet according to Example 4.
(Comparative Example 1)
　比較例１の中間層として、表面層と同じく断熱性の抄紙シートを使用した。具体的には、実施例１と同じ重量比率で原料を混合して得た抄紙スラリーを、湿式抄紙法により抄紙して、厚さ約０．３ｍｍの中間層基材シートを得た。得られた中間層基材シートを、実施例１等と同様に両面に表面層をそれぞれ貼り合せて、比較例１に係る断熱シートを得た。これら実施例１～４、比較例１に係る断熱シートの、中間層の厚さ、断熱シート全体の厚さ、熱伝導率（厚さ方向及び面方向）を、表１に示す。 As the intermediate layer of Comparative Example 1, a heat-insulating papermaking sheet was used as in the surface layer. Specifically, the papermaking slurry obtained by mixing the raw materials in the same weight ratio as in Example 1 was made by a wet papermaking method to obtain an intermediate layer base material sheet having a thickness of about 0.3 mm. The obtained intermediate layer base material sheet was laminated with surface layers on both sides in the same manner as in Example 1 and the like to obtain a heat insulating sheet according to Comparative Example 1. Table 1 shows the thickness of the intermediate layer, the thickness of the entire heat insulating sheet, and the thermal conductivity (thickness direction and surface direction) of the heat insulating sheets according to Examples 1 to 4 and Comparative Example 1.
Figure JPOXMLDOC01-appb-T000001
 （２００℃表裏温度評価試験）
Figure JPOXMLDOC01-appb-T000001
 (200 ° C front and back temperature evaluation test)
　これらのサンプルを用いて、まずサンプルの表裏温度評価試験を行った。具体的には、図６Ａの側面図に示すように、断熱シート１０のサンプルの片面にセラミックヒーターＨＴ（坂口電熱社製ＭＳ－１０００）をアルミテープで固定して、ヒーターＨＴ上面と、ヒーターＨＴに接している断熱シート１０の反対面に熱電対Ｔ０、Ｔ１、Ｔ２、Ｔ３を、図６Ｂ、図６Ｃに示すように取り付けた。この状態で、９．５Ｗ～２０Ｗの出力でヒーターＨＴを２００℃まで昇温した際の、ヒーター温度とシート裏面温度の差より、断熱シート表裏の温度差を測定した。
（可撓性試験） Using these samples, the front and back temperature evaluation test of the samples was first performed. Specifically, as shown in the side view of FIG. 6A, a ceramic heater HT (MS-1000 manufactured by Sakaguchi Electric Heat Co., Ltd.) is fixed to one side of the sample of the heat insulating sheet 10 with aluminum tape, and the upper surface of the heater HT and the heater HT are fixed. Thermocouples T0, T1, T2, and T3 were attached to the opposite surface of the heat insulating sheet 10 in contact with the heat as shown in FIGS. 6B and 6C. In this state, the temperature difference between the front and back of the heat insulating sheet was measured from the difference between the heater temperature and the back surface temperature of the sheet when the heater HT was raised to 200 ° C. with an output of 9.5 W to 20 W.
(Flexibility test)
　さらに各実施例１～４及び比較例１に係る断熱シートについて、可撓性について試験を行った。具体的には、１２０ｍｍ×６５ｍｍに切断した断熱シートを、外径１１０ｍｍの紙管の外周に押し当てて、皺又は割れ等の損傷が発生するかを確認し、評価した。評価は以下のとおり３段階で記述した。〇：発生しない、△：軽微な損傷、×：使用不可となる重大な損傷。これらの結果を、表２に示す。 Further, the heat insulating sheets according to Examples 1 to 4 and Comparative Example 1 were tested for flexibility. Specifically, a heat insulating sheet cut into 120 mm × 65 mm was pressed against the outer periphery of a paper tube having an outer diameter of 110 mm, and it was confirmed whether damage such as wrinkles or cracks occurred and evaluated. The evaluation was described in three stages as follows. 〇: Does not occur, △: Minor damage, ×: Serious damage that makes it unusable. These results are shown in Table 2.
Figure JPOXMLDOC01-appb-T000002
Figure JPOXMLDOC01-appb-T000002
　表２に示すように、断熱層のみで構成した比較例１と比べ、実施例１～４に示すように熱拡散層を挟むことで断熱性能が向上することが判明した。この理由は、熱拡散層の両面に断熱層を設けたことで、断熱層の一部に熱が集中することを避け、面方向に均一に分散されることで、断熱層の全体で断熱性能が発揮され易くなったものと推察される。 As shown in Table 2, it was found that the heat insulating performance was improved by sandwiching the heat diffusion layer as shown in Examples 1 to 4, as compared with Comparative Example 1 composed of only the heat insulating layer. The reason for this is that by providing heat insulating layers on both sides of the heat diffusion layer, heat is prevented from concentrating on a part of the heat insulating layer, and heat is uniformly dispersed in the surface direction, so that the heat insulating performance of the entire heat insulating layer is achieved. It is presumed that it became easier to demonstrate.
　また中間層にアルミニウムを用いた実施例３は、黒鉛紛を用いた実施例１、２に比べて表裏温度差が大きい、いいかえると断熱効果が高くなっていることが判る。さらに実施例４も、実施例３には劣るものの、高い断熱効果を発揮している。実施例３、４のアルミニウムは、厚さ方向と面方向の熱伝導率が同じで、異方性がない一方、実施例１、２の黒鉛紛を用いた熱拡散層は、表１に示したように面方向の熱伝導率が厚さ方向よりも４０～６０倍高い。熱伝導率の異方性が、一見すると断熱性能に貢献しない結果に思われるが、高温度域においては黒鉛の熱伝導率は低下していくため、実際には表１の数値以上に実施例３、４との性能差があり、熱の面方向への拡散速度も低下していたと考えられる。
（絶縁性試験） Further, it can be seen that Example 3 in which aluminum is used for the intermediate layer has a larger temperature difference between the front and back surfaces than Examples 1 and 2 in which graphite powder is used, in other words, the heat insulating effect is higher. Further, Example 4 also exhibits a high heat insulating effect, although it is inferior to Example 3. The aluminum of Examples 3 and 4 has the same thermal conductivity in the thickness direction and the surface direction and has no anisotropy, while the heat diffusion layer using the graphite powder of Examples 1 and 2 is shown in Table 1. As such, the thermal conductivity in the plane direction is 40 to 60 times higher than that in the thickness direction. At first glance, it seems that the anisotropy of thermal conductivity does not contribute to the heat insulation performance, but since the thermal conductivity of graphite decreases in the high temperature range, the examples are actually more than the values in Table 1. It is probable that there was a difference in performance from 3 and 4, and the diffusion rate of heat in the plane direction was also reduced.
(Insulation test)
　次に、絶縁性について試験を行った。ここでは、比較例１と実施例１、２のサンプルを用いて、体積抵抗率はＪＩＳ Ｋ６９１１（１９９５）「熱硬化性プラスチック一般試験方法」に準拠し試験を行った（室温、印加電圧５００Ｖ）。耐電圧ＡＣはＪＩＳ Ｃ２１１０－１「固体電気絶縁材料ー絶縁破壊の強さの試験方法ー第1部：商用周波数交流電圧印加による試験」、耐電圧ＤＣはＪＩＳ Ｃ２１１０－２「固体電気絶縁材料ー絶縁破壊の強さの試験方法ー第２部：直流電圧印可による試験」に準拠し試験を行った（室温、各電圧の印加時間１００／６０［Ｖ／ｓｅｃ］）。この結果を表３に示す。 Next, a test was conducted for insulation. Here, using the samples of Comparative Example 1 and Examples 1 and 2, the volume resistivity was tested in accordance with JIS K6911 (1995) "General test method for thermosetting plastics" (room temperature, applied voltage 500 V). .. Withstand voltage AC is JIS C2110-1 "Solid electrical insulation material-Test method for dielectric breakdown strength-Part 1: Test by applying commercial frequency AC voltage", withstand voltage DC is JIS C2110-2 "Solid electrical insulation material-" The test was carried out in accordance with "Test method for dielectric breakdown strength-Part 2: Test by applying DC voltage" (room temperature, application time of each voltage 100/60 [V / sec]). The results are shown in Table 3.
Figure JPOXMLDOC01-appb-T000003
Figure JPOXMLDOC01-appb-T000003
　表３に示す通り、実施例１、２は導電体である炭素紛を含む中間層を積層しているにも拘らず、体積低効率、絶縁破壊電圧ともに、絶縁体である比較例１と遜色ない結果が得られた。
（温度分布測定） As shown in Table 3, although Examples 1 and 2 are laminated with an intermediate layer containing carbon powder which is a conductor, both low volume efficiency and dielectric breakdown voltage are inferior to Comparative Example 1 which is an insulator. No results were obtained.
(Temperature distribution measurement)
　次に、温度分布測定を行った。ここでは、比較例１と実施例１～４のサンプルを用いて、断熱シート１０の片面に同じくセラミックヒーター（坂口電熱社製ＭＳ－１０００）を取り付け、９．５Ｗ（一定）の出力で加熱開始し、１０分間サーモグラフィカメラにより、シート全体の温度分布を測定した。サーモグラフィカメラで撮像した写真を、図７Ａ～図１１Ｂに示す。これらの図において、図７Ａは実施例１のサンプルをヒーター面から、図７Ｂは裏面側から、それぞれサーモグラフィカメラで撮像した写真である。また図８Ａは実施例２のサンプルをヒーター面から、図８Ｂは裏面側から、それぞれサーモグラフィカメラで撮像した写真である。さらに図９Ａは実施例３のサンプルのヒーター面、図９Ｂは裏面側を、図１０Ａは実施例４のサンプルのヒーター面、図１０Ｂは裏面側を、図１１Ａは比較例１のサンプルのヒーター面、図１１Ｂは裏面側を、それぞれ撮像した写真である。これらの図から、断熱層のみで構成した比較例１では、図１１Ｂに示すように裏面側が高温になっているのに対し、熱拡散層の両面を断熱層で被覆した実施例１～４ではいずれも裏面側の温度上昇を抑えられていることが確認された。特に、厚さが相対的に大きい実施例１では、薄い実施例２に比べて、温度上昇が抑制されると共に、局所的な温度変化も抑制され、面方向に均一な放熱が図られていることが確認された。
（６００℃燃焼試験） Next, the temperature distribution was measured. Here, using the samples of Comparative Example 1 and Examples 1 to 4, a ceramic heater (MS-1000 manufactured by Sakaguchi Electric Heat Co., Ltd.) is also attached to one side of the heat insulating sheet 10, and heating is started at an output of 9.5 W (constant). Then, the temperature distribution of the entire sheet was measured with a thermography camera for 10 minutes. The photographs taken by the thermography camera are shown in FIGS. 7A to 11B. In these figures, FIG. 7A is a photograph of the sample of Example 1 taken from the heater surface, and FIG. 7B is a photograph taken from the back surface side by a thermography camera. Further, FIG. 8A is a photograph of the sample of Example 2 taken from the heater surface, and FIG. 8B is a photograph taken from the back surface side with a thermography camera. Further, FIG. 9A is the heater surface of the sample of Example 3, FIG. 9B is the back surface side, FIG. 10A is the heater surface of the sample of Example 4, FIG. 10B is the back surface side, and FIG. 11A is the heater surface of the sample of Comparative Example 1. 11B is a photograph of the back surface side, respectively. From these figures, in Comparative Example 1 composed of only the heat insulating layer, the back surface side is hot as shown in FIG. 11B, whereas in Examples 1 to 4 in which both sides of the heat diffusion layer are covered with the heat insulating layer. It was confirmed that the temperature rise on the back surface side was suppressed in both cases. In particular, in Example 1 in which the thickness is relatively large, as compared with Example 2 in which the thickness is relatively large, the temperature rise is suppressed, the local temperature change is also suppressed, and uniform heat dissipation in the surface direction is achieved. It was confirmed that.
(600 ° C combustion test)
　さらに実施例に係る断熱シートの難燃性を確認すべく、燃焼試験を行った。ここでは比較例１と実施例１～４のサンプルに対して、ＪＩＳ　Ｌ　１０９１　Ａ－１法（１９９９）試験（４５°ミクロバーナー法）に準じた燃焼試験を行った。ただし加熱時間は、１０分間、加熱温度は６００℃とした。 Furthermore, a combustion test was conducted to confirm the flame retardancy of the heat insulating sheet according to the example. Here, the samples of Comparative Example 1 and Examples 1 to 4 were subjected to a combustion test according to the JIS L 1091 A-1 method (1999) test (45 ° microburner method). However, the heating time was 10 minutes and the heating temperature was 600 ° C.
　治具への取り付けは４５°ミクロバーナ―法と同様に、図１２に示すように各サンプルを斜め４５°の状態で治具に取り付け、またガスバーナーＧＢの接炎部とその裏面に熱電対ＴＣ１、ＴＣ２をそれぞれ取り付けて、ガスバーナーＧＢの炎を当て、接炎部の熱電対ＴＣ１で６００℃となった時点での裏面の熱電対ＴＣ２の温度を測定し、その温度差を計算した。 Similar to the 45 ° micro burner method, each sample is attached to the jig at an angle of 45 ° as shown in Fig. 12, and the thermocouple is attached to the flame contact part of the gas burner GB and its back surface. TC1 and TC2 were attached respectively, the flame of the gas burner GB was applied, the temperature of the thermocouple TC2 on the back surface at the time when the thermocouple TC1 of the flame contact portion reached 600 ° C. was measured, and the temperature difference was calculated.
　さらに、熱電対を取り付けずに治具に取り付けた各サンプルに、１０分間ガスバーナーＧＢの炎を当て、燃焼の有無を観察し、試験後のサンプル両面の状態を撮影し、有機成分が燃焼して白く灰化した部分が見られる場合は、画像処理ソフト「ｌｅａｆａｒｅａｃｏｕｎｔｅｒ＿ｐｌｕｓ３＿３」を使用して面積を測定した。この画像処理ソフトを用いて、灰化面積については、図１３Ａにおいて赤線で囲むように、燃焼で有機分がなくなり、無機分だけとなって白く灰化している面積を測定した。同様に炭化面積については、図１３Ｂにおいて赤線で囲むように、灰化面積を含めて黒く焦げた面積を測定した。 Furthermore, each sample attached to the jig without a thermocouple was exposed to the flame of the gas burner GB for 10 minutes, the presence or absence of combustion was observed, the state of both sides of the sample after the test was photographed, and the organic component was burned. When a white ashed portion was observed, the area was measured using the image processing software "leafareacounter_plus3_3". Using this image processing software, as for the ashed area, as shown by the red line in FIG. 13A, the area where the organic component disappeared by combustion and only the inorganic component was ashed white was measured. Similarly, for the carbonized area, the area burnt black including the ashed area was measured so as to be surrounded by the red line in FIG. 13B.
　実施例１～４と比較例１との各サンプルの燃焼試験後の写真を、図１４Ａ～図１８Ｂにそれぞれ示す。これらの図において、図１４Ａは実施例１のサンプルの燃焼面、図１４Ｂは裏面の写真、図１５Ａは実施例２のサンプルの燃焼面、図１５Ｂは裏面の写真、図１６Ａは実施例３のサンプルの燃焼面、図１６Ｂは裏面の写真、図１７Ａは実施例４のサンプルの燃焼面、図１７Ｂは裏面の写真、図１８Ａは比較例１のサンプルの燃焼面、図１８Ｂは裏面の写真を、それぞれ示している。 The photographs of the samples of Examples 1 to 4 and Comparative Example 1 after the combustion test are shown in FIGS. 14A to 18B, respectively. In these figures, FIG. 14A is a photograph of the combustion surface of the sample of Example 1, FIG. 14B is a photograph of the back surface, FIG. 15A is a photograph of the combustion surface of the sample of Example 2, FIG. 15B is a photograph of the back surface, and FIG. 16A is a photograph of Example 3. The combustion surface of the sample, FIG. 16B is a photograph of the back surface, FIG. 17A is a photograph of the combustion surface of the sample of Example 4, FIG. 17B is a photograph of the back surface, FIG. 18A is a photograph of the combustion surface of the sample of Comparative Example 1, and FIG. 18B is a photograph of the back surface. , Each is shown.
　断熱層のみで構成した比較例１では、図１８Ａに示すように燃焼面の炎に晒されたと思われる部位が、白く灰化した状態が確認される。これは、有機成分が燃焼して無機成分のみがスポット状に残った状態となったものと推察される。また裏面側においても、図１８Ｂに示すように対応する部位で同様に白っぽく灰化した状態が確認された。同じく有機成分が燃焼して無機成分のみがスポット状に残った状態となっているものと考えられる。 In Comparative Example 1 composed of only the heat insulating layer, as shown in FIG. 18A, it is confirmed that the portion of the combustion surface that seems to have been exposed to the flame is ashed white. It is presumed that this is because the organic component burned and only the inorganic component remained in the spot shape. Also on the back surface side, as shown in FIG. 18B, a similarly whitish ashed state was confirmed at the corresponding portion. Similarly, it is considered that the organic component is burned and only the inorganic component remains in the spot shape.
　一方で黒鉛紛の熱拡散層で被覆した実施例１、２ではいずれも燃焼面では燃焼した様子が確認されず、図１４Ａ、図１５Ａに示すように若干焦げたような黒い煤状が確認された。また裏面側においても、実施例１では図１４Ｂに示すように若干のしわの発生が確認されるに留まっている。これは、接着材の樹脂が熱で軟化してしわが発生したためと思われる。 On the other hand, in Examples 1 and 2 coated with the heat diffusion layer of graphite powder, the state of combustion was not confirmed on the combustion surface, and black soot like slightly burnt was confirmed as shown in FIGS. 14A and 15A. rice field. Further, on the back surface side as well, in Example 1, only the occurrence of some wrinkles is confirmed as shown in FIG. 14B. It is considered that this is because the resin of the adhesive material was softened by heat and wrinkles were generated.
　また実施例２でも図１５Ｂに示すように、しわの発生が確認されるものの、燃焼の様子は確認されなかった。このように、実施例１、２においては、表面側を炎に晒しても、裏面側への熱伝導が抑制されていることが確認された。 Also in Example 2, as shown in FIG. 15B, although the occurrence of wrinkles was confirmed, the state of combustion was not confirmed. As described above, in Examples 1 and 2, it was confirmed that the heat conduction to the back surface side was suppressed even if the front surface side was exposed to the flame.
　実施例３、４においては、燃焼面の炎に晒されたと思われる部位に、わずかながら灰化した部分が確認されたが、裏面には灰化が確認されず、裏面側への熱伝導が抑制されていることが確認された。 In Examples 3 and 4, a slightly ashed portion was confirmed in the portion of the combustion surface that was thought to have been exposed to the flame, but ashing was not confirmed on the back surface, and heat conduction to the back surface side was observed. It was confirmed that it was suppressed.
　これらの試験結果をまとめたものを表４に示す。このように、実施例１～４においては、比較例１に比べて難燃性に優れることが確認された。 Table 4 shows a summary of these test results. As described above, it was confirmed that Examples 1 to 4 are superior in flame retardancy as compared with Comparative Example 1.
Figure JPOXMLDOC01-appb-T000004
 （実施例５）
Figure JPOXMLDOC01-appb-T000004
 (Example 5)
　実施例５の表面層として、厚さを０．３０ｍｍとした以外は実施例１と同様に抄紙を行い、表面層基材シートを得た。得られた表面層基材シートを用いて、実施例１と同様の中間層基材シートの両面に積層し、実施例１と同様に貼り合せて、実施例５に係る断熱シートを得た。
（実施例６） As the surface layer of Example 5, papermaking was carried out in the same manner as in Example 1 except that the thickness was 0.30 mm, and a surface layer base material sheet was obtained. Using the obtained surface layer base material sheet, it was laminated on both sides of the intermediate layer base material sheet similar to that of Example 1 and bonded in the same manner as in Example 1 to obtain a heat insulating sheet according to Example 5.
(Example 6)
　実施例６の表面層を作成するため、まず離解させた天然パルプを準備し、マイクロガラス、チョップドガラス、合成シリカ及び珪藻土を均一に分散させた。これにゴム系樹脂を加え、湿式抄紙法で抄紙して、厚さ約０．８０ｍｍの表面層基材シートを得た。このシートの熱伝導率（厚さ方向）は０．０８Ｗ／ｍ・Ｋ、熱伝導率（面方向）は０．０８Ｗ／ｍ・Ｋであった。得られた表面層基材シートを用いて、実施例１と同様の中間層基材シートの両面に積層し、実施例１と同様に貼り合せて、実施例６に係る断熱シートを得た。
（比較例２） In order to prepare the surface layer of Example 6, first, the dissociated natural pulp was prepared, and microglass, chopped glass, synthetic silica and diatomaceous earth were uniformly dispersed. A rubber-based resin was added thereto, and paper was made by a wet papermaking method to obtain a surface layer base material sheet having a thickness of about 0.80 mm. The thermal conductivity (thickness direction) of this sheet was 0.08 W / m · K, and the thermal conductivity (plane direction) was 0.08 W / m · K. Using the obtained surface layer base material sheet, it was laminated on both sides of the intermediate layer base material sheet similar to that of Example 1 and bonded in the same manner as in Example 1 to obtain a heat insulating sheet according to Example 6.
(Comparative Example 2)
　比較例２の表面層として、厚さ０．０３ｍｍのＰＥＴフィルムを用いて、実施例１と同様の中間層基材シートの両面に積層し、実施例１と同様に貼り合せて、比較例２に係る断熱シートを得た。
（平滑度） As the surface layer of Comparative Example 2, a PET film having a thickness of 0.03 mm was used, laminated on both sides of the intermediate layer base material sheet similar to that of Example 1, and bonded in the same manner as in Example 1 to be laminated in the same manner as in Example 1. A heat insulating sheet was obtained.
(Smoothness)
　実施例１、５、６及び比較例２の各サンプルに対して、平滑度を測定した。ここでは、ＪＩＳ　Ｐ　８１１９（１９９８）準拠のデジベック平滑度試験機（東洋精機製作所製ＤＢ－２型）を使用した。真空容器容積は３８０ｍＬであり、上記ＪＩＳ規格の８．ｅ）に従って、試験開始圧力は５０．７ＫＰａ、試験終了圧力は２９．３ＫＰａとした。なお上記ＪＩＳ規格によれば、標準の試験開始圧力は５０．７ＫＰａ、試験終了圧力は４８．０ＫＰａであるが、この条件では測定時間が１５秒より短かったため、試験終了圧力をより低い値に変更して試験を行っている。この結果を表４に示す。なお、比較例２は極めて平滑性が高かったため、測定値が３０００ｓｅｃの時点で測定を中止した。
（バブルポイント試験及び細孔径） The smoothness was measured for each sample of Examples 1, 5, 6 and Comparative Example 2. Here, a decibel smoothness tester (DB-2 type manufactured by Toyo Seiki Seisakusho) conforming to JIS P 8119 (1998) was used. The volume of the vacuum container is 380 mL, which is the JIS standard 8. According to e), the test start pressure was 50.7 KPa and the test end pressure was 29.3 KPa. According to the above JIS standard, the standard test start pressure is 50.7 KPa and the test end pressure is 48.0 KPa, but since the measurement time was shorter than 15 seconds under this condition, the test end pressure was changed to a lower value. And are testing. The results are shown in Table 4. Since Comparative Example 2 had extremely high smoothness, the measurement was stopped when the measured value was 3000 sec.
(Bubble point test and pore diameter)
　実施例１、５、６及び比較例２において、中間層と貼り合せる前の表面層基材シートのバブルポイント値をＪＩＳ　Ｋ　３８３２（１９９０）に準じて測定し、細孔径を計算した。具体的には、４ｃｍ×４ｃｍに切断した表面層のサンプルを、表面張力が１６ｍＮ／ｍのフロリナートＦＣ－４０からなる試験液に浸漬して、完全に試験液が充填されたサンプルをパームポロメーターＣＦＰ－１１００ＡＥ（Ｐｏｒｏｕｓｅ　Ｍａｔｅｒｉａｌｓ　Ｉｎｃ．製）に取り付けて測定を行った。得られたバブルポイント値から下記の式によって細孔径ｄ［μｍ］を算出した。この結果を表４に示す。なお、比較例２は極めて細孔径が小さく、測定下限値を下回り測定不可能であった。
ｄ＝（２．８６×γ）／Ｐ（γ：試験液の表面張力、Ｐ：バブルポイント値［ｋＰａ］）
（透気抵抗度試験） In Examples 1, 5, 6 and Comparative Example 2, the bubble point value of the surface layer base material sheet before being bonded to the intermediate layer was measured according to JIS K 3832 (1990), and the pore diameter was calculated. Specifically, a sample of the surface layer cut into 4 cm × 4 cm is immersed in a test solution made of Fluorinert FC-40 having a surface tension of 16 mN / m, and the sample completely filled with the test solution is a palm poromometer. The measurement was performed by attaching to CFP-1100AE (manufactured by Polouse Materials Inc.). From the obtained bubble point value, the pore diameter d [μm] was calculated by the following formula. The results are shown in Table 4. In Comparative Example 2, the pore diameter was extremely small, and it was below the lower limit of measurement and measurement was impossible.
d = (2.86 × γ) / P (γ: surface tension of test solution, P: bubble point value [kPa])
(Air permeability resistance test)
　同じく、実施例１、５、６及び比較例２において、中間層と貼り合せる前の表面層基材シートの透気抵抗度を、ＪＩＳ　Ｐ　８１１７（２００９）試験に準拠したガーレー標準形デンソメータを用いて測定した。この結果を表４に示す。なお、比較例２は極めて透気抵抗度が高く、測定値が６０００ｓｅｃ／ｍｌの時点で測定を中止した。
（圧縮復元率）
同じく、実施例１、５、６及び比較例２について、中間層と貼り合せる前の表面層基材シートの圧力が１００ｋＰａ時の圧縮率を測定した。測定器にはインストロン社の万能材料試験機５９８５型を用いた。荷重面積を５０ｍｍφとして、速度０．１ｍｍ／ｍｉｎで圧縮し、圧力が１００ｋＰａに達した時点での変位を測定し、シートの初期厚みに対する百分率を計算した。この結果を表４に示す。
（６００℃絶縁保持試験）
４５°ミクロバーナ―法に準じて実施例１、５、６及び比較例２のサンプルを固定し、接炎部に熱電対ＴＣ１を取り付けて、ガスバーナーＧＢの炎を当て、接炎部の熱電対ＴＣ１で６００℃となるよう１０分間加熱した後バーナーを消火した。サンプルを治具に付けたまま放冷して熱電対ＴＣ１を取り外し、接炎部と裏面にデジタルテスターＴＳＴ－ＫＪ８３０（オーム電機製）の電極を当て、導通するか確認した。この結果を表５に示す。（○：導通なし、×：導通あり） Similarly, in Examples 1, 5, 6 and Comparative Example 2, a Garley standard type densometer compliant with the JIS P 8117 (2009) test was used to determine the air permeability resistance of the surface layer base material sheet before being bonded to the intermediate layer. Was measured. The results are shown in Table 4. In Comparative Example 2, the air permeability resistance was extremely high, and the measurement was stopped when the measured value was 6000 sec / ml.
(Compression / recovery rate)
Similarly, in Examples 1, 5, 6 and Comparative Example 2, the compressibility was measured when the pressure of the surface layer base material sheet before bonding with the intermediate layer was 100 kPa. As the measuring instrument, Instron's universal material testing machine type 5985 was used. With a load area of 50 mmφ, compression was performed at a speed of 0.1 mm / min, displacement was measured when the pressure reached 100 kPa, and a percentage of the initial thickness of the sheet was calculated. The results are shown in Table 4.
(600 ° C insulation retention test)
The samples of Examples 1, 5, 6 and Comparative Example 2 were fixed according to the 45 ° microburner method, the thermocouple TC1 was attached to the flame contact portion, the flame of the gas burner GB was applied, and the thermocouple of the flame contact portion was heated. The burner was extinguished after heating at a temperature of 600 ° C. against TC1 for 10 minutes. The thermocouple TC1 was removed by allowing the sample to cool while attached to the jig, and the electrodes of the digital tester TST-KJ830 (manufactured by Ohm Electric) were applied to the flame contact part and the back surface to confirm whether the sample was conducting. The results are shown in Table 5. (○: no continuity, ×: with continuity)
Figure JPOXMLDOC01-appb-T000005
Figure JPOXMLDOC01-appb-T000005
　この結果に示す通り、実施例１、５、６いずれも６００℃加熱後も絶縁性を維持しており、耐熱性が確認された。また実施例の細孔径が小さく、、粉落ちしない層状であるといえる。特に、電源装置のような振動に晒される環境下では、粉落ちしない特性は重要であり、各実施例に係る断熱層を表面層として用いることでより安定して信頼性高く断熱シートを使用できることが確認された。 As shown in this result, all of Examples 1, 5 and 6 maintained the insulating property even after heating at 600 ° C., and the heat resistance was confirmed. Further, it can be said that the pore diameter of the example is small and the powder does not fall off. In particular, in an environment exposed to vibration such as a power supply device, the property of not falling off is important, and by using the heat insulating layer according to each embodiment as a surface layer, a more stable and highly reliable heat insulating sheet can be used. Was confirmed.
　本発明の断熱シートは、二次電池セル同士の間に介在される断熱用のスペーサや、防爆弁とガスダクトの間に介在される緩衝シート、あるいはＥＣＵ等の駆動回路を保護する断熱材等に好適に利用できる。また断熱シートを用いた電源装置は、モバイル電子機器、電池駆動のモータで駆動される動力機器、電気自動車やハイブリッド車等の電動車両、アシスト自転車や電動スクータ等の電動二輪車、電動ゴルフカートやドローン、電力貯蔵用システム等に好適に利用できる。 The heat insulating sheet of the present invention is used as a heat insulating spacer interposed between secondary battery cells, a cushioning sheet interposed between an explosion-proof valve and a gas duct, or a heat insulating material for protecting a drive circuit such as an ECU. It can be suitably used. Power supply devices using heat insulating sheets include mobile electronic devices, power devices driven by battery-powered motors, electric vehicles such as electric vehicles and hybrid vehicles, electric two-wheeled vehicles such as assisted bicycles and electric scooters, electric golf carts and drones. , Can be suitably used for power storage systems and the like.
１００…電源装置
１…二次電池セル
２…側板
１０、１０Ｘ…断熱シート
１１…中間層
１２…表面層
９２…熱伝導シート
９３…第１の絶縁シート
９４…第２の絶縁シート
９５…断熱層
ＨＳ…ホットスポット
ＨＴ…ヒーター
Ｔ０、Ｔ１、Ｔ２、Ｔ３、ＴＣ１、ＴＣ２…熱電対
ＧＢ…ガスバーナー 100 ... Power supply device 1 ... Secondary battery cell 2 ... Side plate 10, 10X ... Insulation sheet 11 ... Intermediate layer 12 ... Surface layer 92 ... Heat conduction sheet 93 ... First insulation sheet 94 ... Second insulation sheet 95 ... Insulation layer HS ... Hotspot HT ... Heaters T0, T1, T2, T3, TC1, TC2 ... Thermocouple GB ... Gas burner

Claims (18)

  1. 　中間層と、
    　前記中間層の表面に積層された表面層と、
    を備え、
    　前記表面層の、厚さ方向の熱伝導率が、０．５０Ｗ／ｍ・Ｋ以下であり、
    　前記中間層の、厚さ方向の熱伝導率が、１．００Ｗ／ｍ・Ｋ以上であり、
    　前記表面層の細孔径が５０μｍ以下である断熱シート。     With the middle class,
    The surface layer laminated on the surface of the intermediate layer and
    Equipped with
    The thermal conductivity of the surface layer in the thickness direction is 0.50 W / m · K or less.
    The thermal conductivity of the intermediate layer in the thickness direction is 1.00 W / m · K or more.
    A heat insulating sheet having a pore diameter of 50 μm or less in the surface layer.
  2. 　中間層と、
    　前記中間層の表面に積層された表面層と、
    を備え、
    　前記表面層の、厚さ方向の熱伝導率が、０．５０Ｗ／ｍ・Ｋ以下であり、
    　前記中間層の、厚さ方向の熱伝導率が、１．００Ｗ／ｍ・Ｋ以上であり、
    　前記表面層の透気抵抗度が、ＪＩＳ　Ｐ　８１１７（２００９）試験に準拠したガーレー標準形デンソメータで３～５０００ｓｅｃ／１００ｍＬである断熱シート。     With the middle class,
    The surface layer laminated on the surface of the intermediate layer and
    Equipped with
    The thermal conductivity of the surface layer in the thickness direction is 0.50 W / m · K or less.
    The thermal conductivity of the intermediate layer in the thickness direction is 1.00 W / m · K or more.
    A heat insulating sheet having an air permeation resistance of the surface layer of 3 to 5000 sec / 100 mL in a Garley standard type densometer conforming to the JIS P 8117 (2009) test.
  3. 　請求項１又は２に記載の断熱シートであって、
    　前記表面層が、前記中間層の両面にそれぞれ積層されてなる断熱シート。     The heat insulating sheet according to claim 1 or 2.
    A heat insulating sheet in which the surface layer is laminated on both sides of the intermediate layer.
  4. 　請求項１～３のいずれか一項に記載の断熱シートであって、
    　前記中間層の、面方向の熱伝導率が、１０００Ｗ／ｍ・Ｋ以下である断熱シート。     The heat insulating sheet according to any one of claims 1 to 3.
    A heat insulating sheet having a thermal conductivity of 1000 W / m · K or less in the plane direction of the intermediate layer.
  5. 　請求項１～４のいずれか一項に記載の断熱シートであって、
    　前記中間層の、厚さ方向の熱伝導率が、３．００Ｗ／ｍ・Ｋ以下である断熱シート。     The heat insulating sheet according to any one of claims 1 to 4.
    A heat insulating sheet having a thermal conductivity of 3.00 W / m · K or less in the thickness direction of the intermediate layer.
  6. 　請求項１～５のいずれか一項に記載の断熱シートであって、
    　前記中間層の、面方向の熱伝導率が、厚さ方向の熱伝導率の５倍以上である断熱シート。     The heat insulating sheet according to any one of claims 1 to 5.
    A heat insulating sheet in which the thermal conductivity in the surface direction of the intermediate layer is 5 times or more the thermal conductivity in the thickness direction.
  7. 　請求項１～６のいずれか一項に記載の断熱シートであって、
    　前記中間層が、抄紙シートで構成されてなる断熱シート。     The heat insulating sheet according to any one of claims 1 to 6.
    A heat insulating sheet in which the intermediate layer is made of a papermaking sheet.
  8. 　請求項１～７のいずれか一項に記載の断熱シートであって、
    　前記中間層が、繊維又は熱伝導フィラーを含んでなる断熱シート。     The heat insulating sheet according to any one of claims 1 to 7.
    A heat insulating sheet in which the intermediate layer contains fibers or a heat conductive filler.
  9. 　請求項１～６のいずれか一項に記載の断熱シートであって、
    　前記中間層が、グラファイト、窒化硼素、アルミニウムのいずれかを含んでなる断熱シート。     The heat insulating sheet according to any one of claims 1 to 6.
    A heat insulating sheet in which the intermediate layer contains any of graphite, boron nitride, and aluminum.
  10. 　請求項１～９のいずれか一項に記載の断熱シートであって、
    　ＪＩＳ　Ｌ　１０９１　Ａ－１法（１９９９）試験に準じて１０分間加熱した際における裏面の灰化面積が５００ｍｍ2以下である断熱シート。     The heat insulating sheet according to any one of claims 1 to 9.
    A heat insulating sheet having an incinerated area of 500 mm 2 or less on the back surface when heated for 10 minutes according to the JIS L 1091 A-1 method (1999) test.
  11. 　請求項１～１０のいずれか一項に記載の断熱シートであって、
    　前記表面層の体積抵抗率が１０10以上である断熱シート。     The heat insulating sheet according to any one of claims 1 to 10.
    A heat insulating sheet having a volume resistivity of 10 10 or more in the surface layer.
  12. 　請求項１～１１のいずれか一項に記載の断熱シートであって、
    　前記表面層が、繊維、充填材、バインダの少なくともいずれかを含んでなる断熱シート。     The heat insulating sheet according to any one of claims 1 to 11.
    A heat insulating sheet in which the surface layer contains at least one of a fiber, a filler, and a binder.
  13. 　請求項１～１２のいずれか一項に記載の断熱シートであって、
    　前記中間層と表面層を接着する接着層が、アクリル系接着材、塩化ビニル系接着材、酢酸ビニル系接着材、ホットメルトの少なくともいずれかである断熱シート。     The heat insulating sheet according to any one of claims 1 to 12.
    A heat insulating sheet in which the adhesive layer for adhering the intermediate layer and the surface layer is at least one of an acrylic adhesive, a vinyl chloride adhesive, a vinyl acetate adhesive, and a hot melt.
  14. 　請求項１～１３のいずれか一項に記載の断熱シートであって、
    　厚さを０．２ｍｍ～６．０ｍｍとしてなる断熱シート。     The heat insulating sheet according to any one of claims 1 to 13.
    A heat insulating sheet with a thickness of 0.2 mm to 6.0 mm.
  15. 　請求項１～１４のいずれか一項に記載の断熱シートであって、
    　前記表面層を、１００ｋＰａで圧縮した時の圧縮率を１０％以上としてなる断熱シート。     The heat insulating sheet according to any one of claims 1 to 14.
    A heat insulating sheet having a compression ratio of 10% or more when the surface layer is compressed at 100 kPa.
  16. 　請求項１～１５のいずれか一項に記載の断熱シートであって、
    　耐熱温度が３００～６００℃である断熱シート。     The heat insulating sheet according to any one of claims 1 to 15.
    A heat insulating sheet with a heat resistant temperature of 300 to 600 ° C.
  17. 　複数の二次電池セルを積層した電源装置に用いる断熱シートであって、
    　中間層と、
    　前記中間層の表面にそれぞれ積層された表面層と、
    を備え、
    　前記表面層の、厚さ方向の熱伝導率が、０．５０Ｗ／ｍ・Ｋ以下であり、
    　前記中間層の、厚さ方向の熱伝導率が、１．００Ｗ／ｍ・Ｋ以上であり、
    　前記表面層の細孔径が、５０μｍ以下である断熱シート。     A heat insulating sheet used for a power supply device in which multiple secondary battery cells are stacked.
    With the middle class,
    The surface layer laminated on the surface of the intermediate layer and
    Equipped with
    The thermal conductivity of the surface layer in the thickness direction is 0.50 W / m · K or less.
    The thermal conductivity of the intermediate layer in the thickness direction is 1.00 W / m · K or more.
    A heat insulating sheet having a pore diameter of 50 μm or less in the surface layer.
  18. 　請求項１７に記載の断熱シートと、
    　前記断熱シートを介在させて積層した複数の二次電池セルと、
    を備える電源装置。     The heat insulating sheet according to claim 17, and the heat insulating sheet.
    A plurality of secondary battery cells laminated with the heat insulating sheet interposed therebetween
    Power supply unit equipped with.
PCT/JP2021/016675 2020-06-18 2021-04-26 Insulating sheet and power supply device comprising same WO2021256093A1 (en)

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2023120436A1 (en) * 2021-12-24 2023-06-29 パナソニックホールディングス株式会社 Battery pack
WO2023120435A1 (en) * 2021-12-24 2023-06-29 パナソニックホールディングス株式会社 Battery pack

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2011108617A (en) * 2009-10-19 2011-06-02 Nitto Denko Corp Heat conduction member and battery pack device using the same
JP2015532778A (en) * 2013-06-19 2015-11-12 アモグリーンテック カンパニー リミテッド Hybrid heat insulating sheet and electronic device equipped with the same
WO2016017670A1 (en) * 2014-07-29 2016-02-04 日東シンコー株式会社 Insulation sheet
US20170034959A1 (en) * 2013-12-31 2017-02-02 Amogreentech Co., Ltd. Composite sheet and portable terminal having same
JP2019147357A (en) * 2018-02-28 2019-09-05 リンテック株式会社 Flame retardant heat insulation sheet and electricity storage module

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2011108617A (en) * 2009-10-19 2011-06-02 Nitto Denko Corp Heat conduction member and battery pack device using the same
JP2015532778A (en) * 2013-06-19 2015-11-12 アモグリーンテック カンパニー リミテッド Hybrid heat insulating sheet and electronic device equipped with the same
US20170034959A1 (en) * 2013-12-31 2017-02-02 Amogreentech Co., Ltd. Composite sheet and portable terminal having same
WO2016017670A1 (en) * 2014-07-29 2016-02-04 日東シンコー株式会社 Insulation sheet
JP2019147357A (en) * 2018-02-28 2019-09-05 リンテック株式会社 Flame retardant heat insulation sheet and electricity storage module

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2023120436A1 (en) * 2021-12-24 2023-06-29 パナソニックホールディングス株式会社 Battery pack
WO2023120435A1 (en) * 2021-12-24 2023-06-29 パナソニックホールディングス株式会社 Battery pack

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