JP7111237B1 - Energy storage device module using heat dissipation sheet, electric mobility - Google Patents

Abstract

A heat dissipation sheet that can prevent deterioration of heat dissipation, an electricity storage device module using the same, and an electric vehicle are provided. A heat dissipation sheet (20) disposed between a heat generating element such as an electricity storage device module (10) and a metal member such as a chassis (5), comprising a base layer (21), a metal foil (22), and a first thermoadhesive resin. Layer 23 is laminated in order, and the first thermoadhesive resin layer 23 is made of acid-modified polyolefin. [Selection drawing] Fig. 4

Description

TECHNICAL FIELD The present invention relates to a heat dissipation sheet arranged between a heating element and a metal member, an electricity storage device module using the same, and an electric mobility. Electric mobility is a device that can be moved using a power storage device such as a battery as a drive source, and examples thereof include cars, ships, railroad vehicles, aircraft, robots, drones, and the like.

A conventional heat-dissipating sheet is disclosed in Patent Document 1. This heat dissipation sheet is used in a battery pack mounted on a vehicle. A battery pack is formed by housing a plurality of battery cells in a housing and is connected to an electronic control unit (ECU). The housing has a resin cover that closes the top opening of the main body made of electrogalvanized steel. A plurality of battery cells are placed on the bottom wall of the main body via heat radiation sheets, and the gaps between the battery cells and the housing are filled with the heat radiation sheets. The heat generated by the battery cells is transferred to the metal housing and the metal heat dissipating member in contact with the housing via the heat dissipation sheet, and is dissipated.

A heat-dissipating sheet is generally formed by highly filling a silicone resin with a heat-conductive filler (see, for example, Patent Document 2).

Japanese Patent Application Laid-Open No. 2020-149931 (pages 4 to 13, FIG. 1) Japanese Patent Application Laid-Open No. 2002-299533 (pages 2 to 4)

However, according to the conventional heat-dissipating sheet, the position of the heat-dissipating sheet is shifted due to vibrations when the battery pack is mounted on a vehicle or the like, and wrinkles or the like are generated. There is a problem that a gap is generated between them and the heat radiation performance to the heating element is lowered.

An object of the present invention is to provide a heat dissipation sheet that can prevent deterioration of heat dissipation, an electricity storage device module using the same, and an electric mobility.

In order to achieve the above object, the present invention provides a heat dissipation sheet disposed between a heating element and a metal member, comprising a substrate layer, a metal foil, and a first thermoadhesive resin layer laminated in this order. and the first thermoadhesive resin layer is made of acid-modified polyolefin.

Further, according to the present invention, in the heat dissipation sheet having the structure described above, the base material layer has a sheet resistance of 2000 MΩ or more and a dielectric breakdown voltage of 5000 V or more.

Further, according to the present invention, in the heat-dissipating sheet having the structure described above, the base material layer is made of polyethylene terephthalate, polybutylene terephthalate, polypropylene, or polyethylene.

Further, according to the present invention, in the heat dissipation sheet having the above structure, the metal foil contains aluminum or copper.

Further, according to the present invention, in the heat dissipation sheet having the above structure, the thickness of the base material layer is smaller than the thickness of the metal foil.

Further, in the heat-dissipating sheet having the above structure, the second heat-adhesive resin layer is laminated on the opposite side of the base material layer to the metal foil, and the second heat-adhesive resin layer is made of acid-modified polyolefin. is characterized by

Further, according to the present invention, in the heat-dissipating sheet having the structure described above, the base material layer is made of an acid-modified polyolefin.

The present invention also provides an electric mobility comprising a heat dissipation sheet having each of the configurations described above, an electricity storage device module in which a plurality of electricity storage devices are housed in a housing, and a metal structure, wherein the electricity storage device module and the structure are provided. It is characterized in that the heat radiation sheet is arranged between the body and the body.

The present invention also provides an electricity storage device module including a heat dissipation sheet having each of the above configurations, a plurality of electricity storage devices, and a metal housing for housing the electricity storage device, wherein the electricity storage device and the housing are separated from each other. It is characterized in that the heat radiation sheet is arranged between them.

According to the present invention, the heat dissipation sheet disposed between the heating element and the metal member is formed by sequentially laminating the base material layer, the metal foil, and the first thermoadhesive resin layer made of acid-modified polyolefin. be. As a result, since the heat-dissipating sheet is thermally adhered to the metal member by the first heat-adhesive resin layer, it is possible to prevent displacement of the heat-dissipating sheet due to vibration or the like. Therefore, it is possible to prevent deterioration of the heat radiation performance of the heating element.

BRIEF DESCRIPTION OF THE DRAWINGS The side view which shows the electric mobility of 1st Embodiment of this invention. 1 is a perspective view showing a power storage device module mounted on an electric mobility device according to a first embodiment of the present invention; FIG. FIG. 1 is a cross-sectional side view showing a state in which an electric storage device module is mounted on the electric mobility according to the first embodiment of the present invention; Detailed view of H part in FIG. BRIEF DESCRIPTION OF THE DRAWINGS A schematic cross-sectional view showing a layer structure of a heat dissipation sheet used for electric mobility according to a first embodiment of the present invention. FIG. 11 is an enlarged cross-sectional side view showing a state in which an electric storage device module is mounted on an electric mobility device according to a second embodiment of the present invention;

<First embodiment>
Embodiments of the present invention will be described below with reference to the drawings. In this embodiment, an electric vehicle will be described as an example of electric mobility. FIG. 1 shows a side view of an electric vehicle 1 that is electric mobility according to the first embodiment. The electric vehicle 1 includes a drive motor 3 as a power source for driving wheels 2 . Under the floor of the vehicle body of the electric vehicle 1, a power storage device module 10 is installed as a drive source for supplying electric power to the drive motor 3. As shown in FIG.

The electric vehicle 1 includes an electric vehicle (EV), a hybrid vehicle (HEV), a plug-in hybrid vehicle (PHEV), and the like. An electric vehicle uses only a motor as a power source, and a hybrid vehicle and a plug-in hybrid vehicle use a motor and an engine as power sources.

FIG. 2 shows a perspective view of the electricity storage device module 10. As shown in FIG. A power storage device module 10 has a plurality of power storage devices 11 arranged side by side and is covered with a housing 13 . The power storage device module 10 may be configured by arranging a plurality of power storage device modules in which a plurality of power storage devices 11 are packaged.

The power storage device 11 is a lithium ion battery, a lithium ion polymer battery, a lithium ion all-solid battery, a lead storage battery, a nickel hydrogen storage battery, a nickel cadmium storage battery, a nickel iron storage battery, a nickel zinc storage battery, a silver zinc oxide storage battery, a metal air battery, and a polyvalent cation. It consists of a secondary battery such as a battery. The electric storage device 11 may be a capacitor (electrolytic capacitor, electric double layer capacitor, lithium ion capacitor, etc.).

Each power storage device 11 is provided with a pair of positive and negative electrode terminals 12 made of metal. The electrode terminals 12 of each power storage device 11 are electrically connected in a predetermined order, and a pair of connection terminals (not shown) protrude from the housing 13 .

The housing 13 is formed of a resin molded product obtained by sheet-molding a laminate including a resin film. The housing 13 may be an injection-molded hard resin product.

FIG. 3 is a side cross-sectional view showing a state in which the power storage device module 10 is mounted on the electric vehicle 1. As shown in FIG. Further, FIG. 4 shows a detailed view of the H portion of FIG. The power storage device module 10 is installed on a chassis 5 that is a metal vehicle structure of the electric vehicle 1 . A heat dissipation sheet 20 is arranged between the power storage device module 10 and the chassis 5 .

FIG. 5 is a schematic cross-sectional view showing the layer structure of the heat dissipation sheet 20. As shown in FIG. The heat-dissipating sheet 20 is formed of a laminate in which a substrate layer 21, a metal foil 22, and a thermoadhesive resin layer 23 (first thermoadhesive resin layer) are laminated in this order. As will be described later, the heat-dissipating sheet 20 is thermally adhered to the chassis 5 (see FIG. 4) by the heat-adhesive resin layer 23, and the power storage device module 10 (see FIG. 4) is installed on the base material layer 21. FIG.

The base material layer 21 is formed of a resin film having high sheet resistance and dielectric breakdown voltage. For example, it is desirable that the sheet resistance of the base layer 21 is 2000 MΩ or more at a predetermined voltage (eg, 100 V, 500 V). Moreover, it is desirable that the dielectric breakdown voltage of the base material layer 21 is 5000 V or higher. As a result, when the connection terminals of the electricity storage device module 10 come into contact with the heat dissipation sheet 20 due to vibration or the like, the electricity storage device module 10 can be prevented from being short-circuited via the metal foil 22 .

As the resin film forming the base material layer 21, polyethylene terephthalate, polypropylene, acid-modified polypropylene, polybutylene terephthalate, polyethylene, acid-modified polyethylene, or the like can be used. The thickness of the base material layer 21 is, for example, 5 to 50 μm. When the thickness of the base material layer 21 is 5 μm or more, dielectric breakdown is less likely to occur. When the thickness of the base material layer 21 is 50 μm or less, a decrease in thermal conductivity of the heat dissipation sheet 20 can be suppressed.

The metal foil 22 is made of metal with high thermal conductivity, and is adhered onto the base layer 21 with an adhesive such as polyurethane or acrylic, or an adhesive resin such as acid-modified polyolefin (none of which is shown). Aluminum, an aluminum alloy, copper, a copper alloy, or the like can be used as the metal foil 22 . The thickness of the metal foil 22 is, for example, 10 to 100 μm. When the thickness of the metal foil 22 is 10 μm or more, a decrease in thermal conductivity of the heat dissipation sheet 20 can be suppressed. If the thickness of the metal foil 22 is 100 μm or less, an increase in the cost of the heat dissipation sheet 20 can be suppressed.

It is more desirable that the thickness of the base material layer 21 is smaller than the thickness of the metal foil 22 . This facilitates heat conduction from the electricity storage device module 10 to the metal foil 22 , and improves the heat conductivity of the heat dissipation sheet 20 .

The thermoadhesive resin layer 23 is formed of a resin having thermoadhesiveness with metal, and is extruded and directly laminated on the metal foil 22 . The heat-adhesive resin layer 23 may be formed by adhering a resin film having heat-adhesiveness to metal onto the metal foil 22 . For this adhesion, an adhesive such as polyurethane or acrylic, or an adhesive resin such as acid-modified polyolefin can be used. Acid-modified polyolefin such as acid-modified polyethylene and acid-modified polypropylene is used as the heat-adhesive resin layer 23 . The thickness of the thermoadhesive resin layer 23 is, for example, 30 to 100 μm.

As an example of the heat dissipation sheet 20, a substrate layer 21 made of polyethylene terephthalate with a thickness of 12 μm, a metal foil 22 made of aluminum with a thickness of 35 μm, and a heat adhesive resin layer 23 made of acid-modified polypropylene with a thickness of 20 μm were laminated. As a result, the following properties were obtained as thermal conductivity and thermal resistance of the heat dissipation sheet 20 . As a result, the heat generated by the power storage device module 10 can be transferred through the heat dissipation sheet 20 and dissipated, as will be described later.

Planar thermal conductivity: 38W/m・K
Thermal conductivity in thickness direction: 0.45 W/m K
Thermal resistance in thickness direction: 1.7×10 ⁻⁴ m ²・K/W

In FIG. 4 , the heat dissipation sheet 20 is thermally adhered to the chassis 5 by the heat-adhesive resin layer 23 , and the power storage device module 10 is placed and fixed on the heat dissipation sheet 20 . The heat generated by the power storage device module 10 is transferred in the thickness direction of the heat dissipation sheet 20 as indicated by an arrow A1 and radiated through the chassis 5 . Further, the heat generated by the electric storage device module 10 is radiated by conducting heat in the plane direction of the metal foil 22 of the heat radiation sheet 20 as indicated by the arrow B1.

In addition, since the heat dissipation sheet 20 is thermally bonded to the chassis 5, it is possible to prevent the positional deviation of the heat dissipation sheet 20 when the electric vehicle 1 vibrates. Therefore, it is possible to prevent deterioration of the heat dissipation performance of the power storage device module 10, which is a heat generating body.

According to this embodiment, the heat dissipation sheet 20 arranged between the power storage device module 10, which is a heating element, and the chassis 5, which is a metal member, is composed of a base layer 21, a metal foil 22, and an acid-modified polyolefin. It is formed by sequentially laminating the adhesive resin layer 23 (first thermoadhesive resin layer). As a result, the heat-dissipating sheet 20 is thermally adhered to the chassis 5 made of the metal member by the heat-adhesive resin layer 23, so that the positional displacement of the heat-dissipating sheet 20 due to vibration or the like can be prevented. Therefore, it is possible to prevent deterioration of the heat radiation performance of the heat generating element to the electricity storage device module 10 .

Further, the base material layer 21 has a sheet resistance of 2000 MΩ or more and a dielectric breakdown voltage of 5000 V or more. Therefore, when electrical components such as the power storage device module 10 are arranged on the heat dissipation sheet 20, short circuits of the electrical components can be prevented.

Moreover, since the base material layer 21 is polyethylene terephthalate, polybutylene terephthalate, polypropylene, or polyethylene, the base material layer 21 having high sheet resistance and dielectric breakdown voltage can be easily realized.

Moreover, since the metal foil 22 contains aluminum or copper, the heat dissipation sheet 20 with high thermal conductivity can be easily realized.

Moreover, when the thickness of the base material layer 21 is smaller than the thickness of the metal foil 22, heat is easily conducted from the heating element to the metal foil 22, and the heat conductivity of the heat dissipation sheet 20 can be improved.

Moreover, a heat dissipation sheet 20 is arranged between the power storage device module 10 housing a plurality of power storage devices 11 in the housing 13 and the chassis 5 which is the metal structure of the electric vehicle 1 . Therefore, the heat dissipation sheet 20 can be prevented from being displaced due to the vibration of the electric vehicle 1 , and the heat generated by the power storage device module 10 can be reliably dissipated through the heat dissipation sheet 20 and the chassis 5 .

<Second embodiment>
Next, FIG. 6 is an enlarged cross-sectional side view showing a state in which an electric storage device module is mounted on an electric vehicle, which is electric mobility according to the second embodiment. For convenience of explanation, the same parts as those of the first embodiment shown in FIGS. 1 to 5 are given the same reference numerals. In this embodiment, an electricity storage device module 10 has a metal housing 13, and a heat dissipation sheet 20 similar to that of the first embodiment is arranged between the electricity storage device 11 and the housing 13. FIG. Other parts are the same as in the first embodiment.

The power storage device module 10 is installed on the chassis 5 . A housing 13 of the power storage device module 10 is made of metal such as an electrogalvanized steel plate. A heat-dissipating sheet 20 is thermally adhered to the inner surface of the housing 13 by a heat-adhesive resin layer 23 , and the power storage device 11 is placed on the heat-dissipating sheet 20 .

The heat generated by the power storage device 11 as a heat generator is transferred through the heat dissipation sheet 20 in the thickness direction as indicated by an arrow A2, and radiated through the housing 13 and the chassis 5. FIG.

Since the heat dissipation sheet 20 is thermally bonded to the metal casing 13, it is possible to prevent the heat dissipation sheet 20 from being displaced when the electric vehicle 1 vibrates. Therefore, it is possible to prevent deterioration of the heat dissipation performance of the electricity storage device 11, which is a heating element.

In this embodiment, as in the first embodiment, the heat dissipation sheet 20 arranged between the electricity storage device 11 which is a heating element and the housing 13 which is a metal member is composed of a base layer 21 and a metal foil 22. , and a heat-adhesive resin layer 23 (first heat-adhesive resin layer) made of acid-modified polyolefin are laminated in order. As a result, the heat-dissipating sheet 20 is thermally adhered onto the housing 13 made of the metal member by the heat-adhesive resin layer 23, so that the positional displacement of the heat-dissipating sheet 20 due to vibration or the like can be prevented. Therefore, it is possible to prevent the deterioration of the heat radiation performance of the heat generating element with respect to the electricity storage device 11 .

When the electric storage device 11 is covered with a metal case, it is more preferable to use acid-modified polyolefin (acid-modified polypropylene, acid-modified polyethylene, etc.) having metal adhesiveness as the base material layer 21 . As a result, the heat dissipation sheet 20 can be thermally bonded and fixed to the surface of the electricity storage device 11 by the base layer 21 , and the positional deviation of the heat dissipation sheet 20 with respect to the electricity storage device 11 and the housing 13 can be prevented. . Therefore, it is possible to further prevent deterioration of the heat dissipation performance of the electricity storage device 11, which is a heating element.

In this embodiment, a heat dissipation sheet 20 may be arranged between the power storage device module 10 and the chassis 5, which is a metal structure, as in the first embodiment. At this time, a heat-adhesive resin layer (second heat-adhesive resin layer) made of acid-modified polyolefin similar to the heat-adhesive resin layer 23 may be provided on the upper surface of the base material layer 21, and the base material layer 21 may be acid-modified. It may be formed from modified polyolefin. As a result, the metallic housing 13 and the heat radiation sheet 20 are thermally bonded to each other, and the positional deviation of the heat radiation sheet 20 can be prevented more reliably.

In addition, in the first and second embodiments, the heat dissipation sheet 20 is mounted on the electric vehicle 1, but the heat dissipation sheet 20 may be arranged between the heating element and the metal member in other equipment. For example, the heat dissipation sheet 20 can be arranged between the electronic component of the heat generating body of the electronic device and the heat sink made of metal.

INDUSTRIAL APPLICABILITY According to the present invention, it can be used for electric mobility, electronic equipment, etc. in which a heat dissipation sheet is arranged between a heating element and a metal member.

REFERENCE SIGNS LIST 1 electric vehicle 2 wheel 3 drive motor 5 chassis 10 power storage device module 11 power storage device 12 electrode terminal 13 housing 20 heat dissipation sheet 21 base layer 22 metal foil 23 thermoadhesive resin layer

Claims (6)

An electric mobility comprising: a heat dissipation sheet; an electricity storage device module housing a plurality of electricity storage devices in a housing; and a metallic structure, wherein the heat dissipation sheet includes a base layer, a metal foil, The first thermoadhesive resin layer is made of an acid-modified polyolefin, and is thermally adhered to the structure by the first thermoadhesive resin layer. The electric mobility , wherein the heat dissipation sheet is arranged between the power storage device module and the structure . A second thermoadhesive resin layer is laminated on the opposite side of the base material layer to the metal foil, the second thermoadhesive resin layer is made of acid-modified polyolefin, and the second thermoadhesive resin layer causes the The electric mobility according to claim 1, wherein a heat dissipation sheet is thermally adhered to the power storage device module . 2. The electric mobility according to claim 1, wherein the base material layer is made of acid-modified polyolefin, and the heat dissipation sheet is thermally adhered to the power storage device module by the base material layer . An electricity storage device module comprising : a heat dissipation sheet; a plurality of electricity storage devices; the first heat-adhesive resin layer is made of an acid-modified polyolefin, and the first heat-adhesive resin layer is heat-bonded to the housing. An electricity storage device module , wherein a sheet is arranged between the electricity storage device and the housing . A second thermoadhesive resin layer is laminated on the opposite side of the base material layer to the metal foil, the second thermoadhesive resin layer is made of acid-modified polyolefin, and the second thermoadhesive resin layer causes the 5. The electricity storage device module according to claim 4, wherein a heat radiation sheet is thermally bonded to the electricity storage device. 5. The electricity storage device module according to claim 4, wherein the base material layer is made of acid-modified polyolefin, and the heat dissipation sheet is thermally adhered to the electricity storage device by the base material layer .

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