JP6851289B2 - Heat dissipation structure and battery with it - Google Patents

Description

The present invention relates to a heat radiating structure and a battery including the heat radiating structure.

Control systems for automobiles, aircraft, ships, or household or commercial electronic devices are becoming more accurate and complex, and the density of small electronic components on circuit boards is increasing. .. As a result, it is strongly desired to solve the failure and shortening of the life of electronic components due to heat generation around the circuit board.

In order to realize quick heat dissipation from the circuit board, conventionally, the circuit board itself is made of a material having excellent heat dissipation, a heat sink is attached, or a means of driving a heat dissipation fan is used alone or in combination. It is done. Of these, a method in which the circuit board itself is made of a material having excellent heat dissipation, for example, diamond, aluminum nitride (AlN), cBN, or the like, makes the cost of the circuit board extremely high. Further, the arrangement of the heat radiating fan causes problems such as failure of the rotating device called the fan, maintenance necessity for preventing the failure, and difficulty in securing the installation space. On the other hand, the heat radiating fin is a simple one that can increase the surface area and further improve the heat radiating property by forming a large number of columnar or flat plate-shaped projecting portions using a metal having high thermal conductivity (for example, aluminum). Since it is a member, it is widely used as a heat-dissipating component (see Patent Document 1).

By the way, at present, there are active movements around the world to gradually convert conventional gasoline-powered vehicles or diesel-powered vehicles to electric vehicles for the purpose of reducing the burden on the global environment. In particular, in addition to European countries such as France, the Netherlands and Germany, China has also declared that it will completely switch from gasoline and diesel vehicles to electric vehicles by 2040. The spread of electric vehicles has issues such as the development of high-performance batteries and the installation of a large number of charging stations. In particular, technological development for enhancing the charging and power generation functions of lithium-based automobile batteries has become a major issue. It is well known that the above-mentioned automobile battery cannot fully exert its charging and power generation functions at a high temperature of 60 degrees Celsius or higher. For this reason, it is important to improve the heat dissipation of the battery as well as the circuit board described above.

In order to quickly dissipate heat from the battery, place the water-cooled pipe in a metal housing with excellent thermal conductivity such as aluminum, place a large number of battery cells in the housing, and place the battery cell and the bottom of the housing. A structure in which an adhesive rubber sheet is sandwiched between the two is adopted. Hereinafter, description will be made with reference to the drawings.

FIG. 8 shows a schematic cross-sectional view of a conventional battery. In the battery 100 of FIG. 8, a large number of battery cells 101 are arranged on an inner bottom surface 103 of a housing 102 made of aluminum or an aluminum-based alloy. The bottom 104 of the housing 102 is provided with a water cooling pipe 105 for flowing cooling water. The battery cell 101 is fixed in the housing 102 with a rubber sheet (for example, a sheet made of room temperature curable silicone rubber) 106 sandwiched between the battery cell 101 and the bottom portion 104. In the battery 100 having such a structure, the battery cell 101 transfers heat to the housing 102 through the rubber sheet 106, and the heat is effectively removed by water cooling.

Japanese Patent Application Laid-Open No. 2008-24399

However, the heat dissipation structure of the conventional battery 100 as shown in FIG. 8 has the following problems to be solved. Since the rubber sheet 106 has lower thermal conductivity than aluminum or graphite, it is difficult to efficiently transfer heat from the battery cell 101 to the housing 102. Further, a method of sandwiching a spacer such as graphite instead of the rubber sheet 106 is also conceivable. However, since the lower surfaces of the plurality of battery cells 101 are not flat and have steps, a gap is generated between the battery cells 101 and the spacer, and the heat transfer efficiency is lowered. This also applies when the spacer is brought into contact with the circuit board.

Further, it is known that the battery cell 101 has a reduced charging and power generation function not only in a high temperature region but also in a low temperature region of 0 degrees Celsius or less. Therefore, the conventional heat dissipation structure alone cannot cope with the deterioration of the function in the low temperature range. In addition, the electronic components on the circuit board may also deteriorate in function in a low temperature range.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a heat radiating structure having excellent heat radiating efficiency and also having a heat generating function, and a battery provided with the heat radiating structure.

(1) The heat radiating structure according to the embodiment for achieving the above object is a heat radiating structure for conducting heat from the heat source to the cooling member between the heat source and the cooling member, and is made of metal or carbon. Alternatively, the heat conductive sheet is made of at least one of ceramics and is curved or bent between the heat source and the cooling member, and at least in the inner space formed by the bending or bending of the heat conductive sheet. A rubber-like elastic body to be arranged, a rubber sheet for closely fixing the heat conductive sheet and the heat source, and an energizing electrode capable of supplying power to heat the heat conductive sheet, the rubber sheet or the rubber-like elastic body. Be prepared. "Curved" in the present application means drawing an arc. Further, the "bending" in the present application means that the bending is sharper than the bending.

(2) In the heat radiating structure according to another embodiment, it is preferable that the heat conductive sheet has one or more U-shaped curved portions or V-shaped bent portions.

(3) In the heat radiating structure according to another embodiment, the rubber-like elastic body is divided in the thickness direction of the inner space, and the heat conductive sheet is flattened by opening the curvature or bending. It is preferable that the case can be followed.

(4) In the heat radiating structure according to another embodiment, it is preferable that the heat conductive sheet is a carbon sheet and the current-carrying electrode is a silver thin film formed on the heat conductive sheet.

(5) In the heat radiating structure according to another embodiment, the carbon sheet is preferably a sheet containing carbon fibers and a resin.

(6) In the heat radiating structure according to another embodiment, the rubber sheet is preferably a sheet made of silicone rubber.

(7) In the battery according to one embodiment, the above-mentioned heat dissipation structure is arranged between a battery cell as a heat source and a housing as a cooling member in which the battery cell is arranged.

According to the present invention, it is possible to provide a heat dissipation structure having excellent heat dissipation efficiency and also having a heat generation function, and a battery provided with the heat dissipation structure.

FIG. 1 is a partially transmitted plan view (1A) of the heat radiation structure according to the first embodiment, a sectional view taken along line AA in the partially transmitted plan view, an enlarged view (1B) of a part P, and a part thereof. A sectional view taken along line BB in the transmission plan view and an enlarged view (1C) of a part of Q are shown. 2A and 2B are a schematic cross-sectional view (2A) of the battery according to the first embodiment including the heat dissipation structure of FIG. 1, a cross-sectional view (2B) of a part C of the schematic cross-sectional view before fixing the battery cell, and the schematic cross-sectional view. An enlarged view (2C) of a part C in the figure is shown. FIG. 3 shows a cross-sectional view of a part of an electronic device in which the heat radiating structure according to the first embodiment is arranged between the circuit board and the heat sink. FIG. 4 shows each cross-sectional view (4A) before and after the curved deformation of the heat radiating structure according to the third embodiment and each cross-sectional view (4B) of the same view of the modified example. FIG. 5 shows a cross-sectional view of the heat radiating structure according to the fourth embodiment, which is the same as (1C). FIG. 6 shows each cross-sectional view before and after the curved deformation of the modified example of the heat radiating structure according to the fourth embodiment. FIG. 7 shows a cross-sectional view (7A) of the heat radiating structure according to the fifth embodiment and the same as (1C), and each cross-sectional view (7B) before and after fixing the battery cell in the cross-sectional view. FIG. 8 shows a schematic cross-sectional view of a conventional battery.

Next, each embodiment of the present invention will be described with reference to the drawings. It should be noted that each of the embodiments described below does not limit the invention according to the claims, and all of the elements and combinations thereof described in each embodiment are the means for solving the present invention. Is not always required.

(First Embodiment)
FIG. 1 is a partially transmitted plan view (1A) of the heat radiation structure according to the first embodiment, a sectional view taken along line AA in the partially transmitted plan view, an enlarged view (1B) of a part P, and a part thereof. A sectional view taken along line BB in the transmission plan view and an enlarged view (1C) of a part of Q are shown.

The heat radiating structure 1 according to the first embodiment is a heat radiating structure located between the heat source and the cooling member for conducting heat from the heat source to the cooling member. The heat radiating structure 1 includes a heat conductive sheet 11, a rubber-like elastic body 12, rubber sheets 13 and 13, and current-carrying electrodes 14 and 14. The heat conductive sheet 11 is made of at least one of metal, carbon, or ceramics, and is a sheet that is curved or bent between the heat source and the cooling member. The rubber-like elastic body 12 is an elastic body that is at least arranged in the inner space formed by bending or bending the heat conductive sheet 11. The rubber sheets 13 and 13 are sheets for closely fixing the heat conductive sheet 11 and the heat source. The energizing electrodes 14 and 14 are a set of two electrodes formed apart from each other on the heat conductive sheet 11 in order to energize the heat conductive sheet 11 and heat the heat conductive sheet 11 itself. However, the energizing electrodes 14 and 14 may be electrodes capable of supplying power for heating the rubber sheets 13 and 13 or the rubber-like elastic body 12 instead of the heat conductive sheet 11, and in such a case, one of them. The current supplied from the energizing electrode 14 may flow into the other energizing electrode 14 via the rubber sheets 13, 13 or the rubber-like elastic body 12, or the heater connecting the energizing electrodes 14, 14 to each other. It may be formed on the rubber sheets 13, 13 or the rubber-like elastic body 12 so that the current flows through the heater. The term "carbon" as used in the present application includes various crystal structures made of carbon (element symbol: C) such as graphite, carbon black having lower crystallinity than graphite, diamond, and diamond-like carbon having a structure similar to diamond. Interpreted in a broad sense.

(1) Heat Conductive Sheet The heat conductive sheet 11 includes one U-shaped curved portion in this embodiment. However, the heat conductive sheet 11 may include one V-shaped bent portion instead of the U-shaped curved portion. The heat conductive sheet 11 is preferably a sheet made of carbon, and more preferably a sheet containing carbon fibers and a resin. In each embodiment of the present application, the heat conductive sheet 11 is a thin sheet obtained by curing a material in which graphite fibers and carbon particles are mixed and dispersed in a resin. The resin may exceed 50% by mass with respect to the total mass of the heat conductive sheet 11, or the graphite fibers and carbon particles may exceed 50% by mass with respect to the total mass of the resin. That is, the heat conductive sheet 11 may use resin as the main material, or graphite fibers or carbon particles as the main material, as long as the heat conduction is not significantly hindered. As the resin, for example, a thermoplastic resin can be preferably used. As the thermoplastic resin, a resin having a high melting point that does not melt when conducting heat from a heat source is preferable, and for example, polyphenylene sulfide (PPS), polyetheretherketone (PEEK), polyamideimide (PAI) and the like are used. It can be preferably mentioned. The resin is dispersed in the gaps between the graphite fibers, for example, in the form of particles in the state before molding of the heat conductive sheet 11. In addition to graphite fibers and resins, the heat conductive sheet 11 may be dispersed with aluminum nitride or diamond as a filler for further enhancing heat conduction.

The heat conductive sheet 11 is preferably more excellent in heat conductivity than the rubber-like elastic body 12 described later, and it does not matter whether or not the heat conductive sheet 11 is excellent in conductivity. The thermal conductivity of the heat conductive sheet 11 is preferably 10 W / mK or more. In this embodiment, the current-carrying electrodes 14 and 14 are used to allow an electric current to flow through the heat conductive sheet 11 itself so that the heat conductive sheet 11 generates heat. Therefore, carbon fibers (preferably graphite fibers) and carbon particles are impregnated in the heat conductive sheet 11 to form a network in which current easily flows in the heat conductive sheet 11. When the current flowing between the energizing electrodes 14 and 14 flows through the rubber sheets 13, 13, the rubber-like elastic body 12 or another electric circuit (the circuit functions as a heater), the heat conductive sheet 11 becomes conductive. It does not have to be excellent, it may just have thermal conductivity. In that case, the heat conductive sheet 11 may be a sheet containing aluminum nitride, diamond, diamond carbon (which has lower conductivity than graphite) and the like. The thickness of the heat conductive sheet 11 is not limited as long as it is a bendable (or flexible) sheet, but the thickness is preferably 0.3 to 5 mm, more preferably 0.3 to 1 mm. However, since the thermal conductivity of the heat conductive sheet 11 decreases as the thickness increases, it is necessary to determine the thickness by comprehensively considering the strength, flexibility and heat conductivity of the sheet. preferable.

(2) Rubber-like elastic body The rubber-like elastic body 12 is an elastic body arranged in the space inside the curved or bent heat conductive sheet 11, and is located between the heat source and the cooling member to exhibit cushioning properties. It has a function and a function as a protective member for preventing the heat conductive sheet 11 from being damaged by a load applied to the heat conductive sheet 11. The rubber-like elastic body 12 is a member having a lower thermal conductivity than the heat conductive sheet 11. Therefore, the heat from the heat source is mainly transmitted through the curved or bent heat conductive sheet 11 after passing through the rubber sheet 13, and is transferred to the cooling member via the rubber sheet 13.

The rubber-like elastic body 12 is preferably a thermosetting elastomer such as silicone rubber, urethane rubber, isoprene rubber, ethylene propylene rubber, natural rubber, ethylene propylene diene rubber, nitrile rubber (NBR) or styrene butadiene rubber (SBR); It is configured to contain a thermoplastic elastomer such as urethane-based, ester-based, styrene-based, olefin-based, butadiene-based, and fluorine-based, or a composite thereof. The rubber-like elastic body 12 is preferably made of a material having high heat resistance that can maintain its shape without being melted or decomposed by the heat transmitted through the heat conductive sheet 11. In this embodiment, the rubber-like elastic body 12 is more preferably composed of a urethane-based elastomer impregnated with silicone or a silicone rubber. The rubber-like elastic body 12 may be configured by dispersing a filler typified by aluminum nitride, cBN, diamond particles, etc. in the rubber in order to enhance its thermal conductivity as much as possible.

(3) Rubber Sheets The rubber sheets 13 and 13 are sheets arranged between the heat source and the heat conductive sheet 11 and between the cooling member and the heat conductive sheet 11 in this embodiment. The rubber sheets 13 and 13 are separated and fixed from both ends of the U-shaped curved heat conductive sheet 11 to a region that is held substantially horizontal. However, as shown in the embodiment described later, the heat conductive sheet 11 curved in a U shape may be provided with one rubber sheet 13 that covers the outside of the heat conductive sheet 11 in a U shape.

The rubber sheet 13 can be formed of various types of elastic bodies similar to the rubber-like elastic body 12 described above, but is excellent in thermal conductivity because it is necessary to quickly transfer heat from a heat source to the heat conductive sheet 11. It is preferable that the sheet contains a silicone rubber. When the rubber sheet 13 is mainly composed of silicone rubber, it is preferable to disperse a highly thermally conductive filler such as alnium nitride or aluminum in the silicone rubber. Further, as the rubber sheet 13 made of silicone rubber, a silicone rubber in which a silicone resin is combined with a bifunctional silicone raw rubber can be exemplified in order to enhance the adhesiveness. The silicone resin is preferably an MQ resin. MQ resin is a four-way branched Q unit with a structure in which oxygen atoms are bonded to four Si bonds, and in order to stop the reactivity at the end, one Si bond is used. It is a resin to which a one-branched M unit having a structure in which oxygen atoms are bonded is added. Further, as the silicone resin, it is preferable to use a resin having many hydroxyl groups bonded because the adhesiveness of the silicone rubber can be enhanced.

The rubber sheet 13 has a function of improving the adhesion between the uneven heat source and the heat conductive sheet 11. The rubber sheet 13 is not particularly limited in hardness as long as it has heat resistance and adhesiveness, but in particular, if it is a sheet mainly made of silicone rubber, it is 60 degrees or less, preferably 40 degrees or less, more preferably 40 degrees or less based on Shore 00. Is 10 degrees or less. This is because the lower the hardness of the rubber sheet 13, the easier it is to absorb the unevenness of the heat source. The thickness of the rubber sheet 13 is preferably 0.3 to 5 mm, more preferably 0.7 to 3 mm, and even more preferably 1 to 2.5 mm. However, the thickness of the rubber sheet 13 is preferably determined according to conditions such as unevenness of the heat source and rubber hardness.

(4) Energizing electrodes The energizing electrodes 14 and 14 are electrodes that connect one to the feeding line and the other to the ground line. In this embodiment, the energizing electrodes 14 and 14 are thin films formed by applying a paste containing a metal filler to the surface of the heat conductive sheet 11. As the paste containing a metal filler, a paste containing a silver filler (silver paste) can be preferably exemplified. In that case, the thin film becomes a silver thin film. However, other than silver, the current-carrying electrodes 14 and 14 may be produced by applying a paste containing a metal material having a relatively excellent conductivity. Further, the method of forming the energizing electrodes 14 and 14 is not particularly limited, and for example, brush coating or printing can be adopted. In this embodiment, the energizing electrodes 14 and 14 are formed between the heat conductive sheet 11 and the rubber sheet 13 as shown in FIG. 1 (1B). However, the energizing electrodes 14 and 14 may be formed so as to penetrate the rubber sheet 13. Further, the current-carrying electrodes 14 and 14 may be formed in addition to the portion where the rubber sheet 13 is formed. The power feeding lead wire connected to the current-carrying electrodes 14 and 14 may or may not be included in the heat dissipation structure 1. Further, the power feeding means connected to the lead wire may or may not be included in the heat radiating structure 1. This also applies to the embodiments described later.

(5) Suitable production method (a) A felt-like sheet is produced by stirring resin fibers, graphite fibers (or particles) and carbon particles typified by PPS or the like in water in the manner of papermaking.
(B) Subsequently, the felt-like sheet is set in the mold, and the uncured rubber-like elastic body composition typified by the curable silicone rubber composition is provided on the felt-like sheet in the mold. , Perform molding under heating and pressurization. As a result, a bendable or bendable sheet in which the heat conductive sheet 11 and the rubber-like elastic body 12 are laminated is completed.
(C) Next, a silver paste is printed on the edge of the heat conductive sheet 11 side, and after drying, the current-carrying electrodes 14 and 14 are formed.
(D) A heat conductive silicone tape is attached to a surface in contact with the heat source and the cooling member (a region that does not overlap with the positions of the energizing electrodes 14 and 14), and rubber sheets 13 and 13 are formed on the heat conductive sheet 11.
(E) Finally, the lead wire is connected to the energizing electrodes 14 and 14.

FIG. 2 is a schematic cross-sectional view (2A) of the battery according to the first embodiment including the heat dissipation structure of FIG. 1, a cross-sectional view (2B) of a part C of the schematic cross-sectional view before fixing the battery cell, and the schematic cross-sectional view. An enlarged view (2C) of a part C in the figure is shown.

The battery 20 shown in FIG. 2 (2A) is, for example, a battery for an electric vehicle and includes a large number of battery cells 21. The battery cell 21 is arranged on the inner bottom surface 23 of the housing 22 made of aluminum or an aluminum-based alloy. The bottom 24 of the housing 22 is provided with a water cooling pipe 25 for flowing cooling water. The battery cell 21 is fixed in the housing 22 with the heat radiating structure 1 of FIG. 1 sandwiched between the battery cell 21 and the bottom portion 24. In the battery 20 having such a structure, the battery cell 21 transfers heat to the housing 22 through the heat radiating structure 1 and is effectively removed by water cooling. The battery cell 21 in the battery 20 is an example of a heat source. The bottom 24 of the battery 20 (where the water cooling pipe 25 is installed) is an example of a cooling member.

As shown in FIGS. 2B and 2C, when the heat radiating structure 1 is arranged on the inner bottom surface 23 and a large number of battery cells 21 are arranged from above, the heat radiating structure 1 is in the thickness direction thereof. It is compressed under load. Many battery cells 21 have irregularities on their bottom surfaces rather than a perfect flat surface. In this embodiment, as shown in FIG. 2B, the rubber sheet 13 on the battery cell 21 side of the heat dissipation structure 1 needs to have a thickness of d or more because of the unevenness of the longest step d. Generally, d is considered to be 1 mm or less. Therefore, the thickness of the rubber sheet 13 is preferably 1 mm or more. Not only the rubber sheet 13 is compressed, but also the rubber-like elastic body 12 is compressed from the thickness t0 to the thickness t1 (<t0) under the load from many battery cells 21. The direction in which the plurality of battery cells 21 are arranged in parallel may be a direction from the U-shaped open side of the heat conductive sheet 11 of the heat radiation structure 1 toward the curved convex portion side, or a direction orthogonal to the U-shaped convex portion side. This also applies to the third and subsequent embodiments.

(Second Embodiment)
Next, the second embodiment of the present invention will be described. In the second embodiment, the parts common to the first embodiment are designated by the same reference numerals, and duplicate description will be omitted. The second embodiment shows a mode in which the same heat dissipation structure as that of the first embodiment is mounted on a circuit board of an electronic device.

FIG. 3 shows a cross-sectional view of a part of an electronic device in which the heat radiating structure according to the first embodiment is arranged between the circuit board and the heat sink.

The electronic device 30 includes a printed circuit board (hereinafter, referred to as “PCB” or simply “circuit board”) 33 in the housing 31, and also includes a heat sink 32 at a predetermined distance from the PCB 33. In this embodiment, the heat sink 32 is preferably made of a metal material having high thermal conductivity represented by aluminum or an aluminum alloy, and includes a large number of fins for enhancing heat dissipation. The heat sink 32 may include pins in place of or with the fins.

It is equipped with many electronic components that are electrically connected or disconnected from the wiring drawn on the front surface (upper surface in FIG. 3) and the back surface (lower surface in FIG. 3) of the PCB 33. ing. The electronic component is not limited to a specific component, and in this embodiment, the electronic component includes a capacitor 34 and an IC chip 35. In this embodiment, the capacitor 34 and the IC chip 35 are connected to both the front and back surfaces of the PCB 10. When the capacitor 34 and the IC chip 35 are mounted on the back surface of the PCB 33, it is difficult to directly connect the PCB 33 to the front surface of the heat sink 32. Therefore, the heat radiating structure 1 is arranged in the gap between the PCB 33 and the heat sink 32, and heat is transferred from the circuit board 33 to the heat sink 32 via the heat conductive sheet 11 to realize efficient heat radiating. In this embodiment, the circuit board 33 is an example of a heat source. The heat sink 32 is an example of a cooling member. As shown in this embodiment, the heat radiating structure 1 can be mounted not only on the battery 20 as in the first embodiment but also on the electronic device 30 as in the second embodiment.

(Third Embodiment)
Next, a third embodiment of the present invention will be described. In the third embodiment, the parts common to the first embodiment are designated by the same reference numerals, and duplicate description will be omitted. The third embodiment shows a modified example of the heat radiating structure of the first embodiment.

FIG. 4 shows each cross-sectional view (4A) before and after the curved deformation of the heat radiating structure according to the third embodiment and each cross-sectional view (4B) of the same view of the modified example.

The heat radiating structure 1a according to the third embodiment includes a rubber-like elastic body 12a in the inner space when the heat conductive sheet 11 is curved and deformed. The rubber-like elastic body 12a includes a notch 40 from the U-shaped open side of the heat conductive sheet 11 toward the curved portion. The length of the notch 40 is a length that does not completely divide the rubber-like elastic body 12a. The configuration other than this point is common to the heat radiating structure 1 according to the first embodiment.

As shown in the lower part of FIG. 4A, the heat radiating structure 1a has a heat conductive sheet 11 as a flat plate, a rubber-like elastic body 12a is laminated on one surface thereof, and a rubber sheet 13 is laminated on the opposite surface. , 13 are separated and laminated. When the heat radiating structure 1a is curved and deformed so as to be bent from a substantially central portion in the length direction (horizontal direction in the drawing) toward the rubber-like elastic body 12a, the shape shown above in FIG. 4 (4A) is obtained.

The heat radiating structure 1b shown in FIG. 4 (4B) includes a notch 41 in which the notch 40 of the heat radiating structure 1a is further lengthened. The notch 41 divides the rubber-like elastic body 12 into a first rubber-like elastic body 12a and a second rubber-like elastic body 12b. By forming such a notch 41 in the rubber-like elastic body 12, the heat radiating structure 1b is substantially centered in the length direction (left-right direction in the drawing) of the heat radiating structure 1b, similarly to the heat radiating structure 1a. By bending and deforming the portion toward the rubber-like elastic body 12 side, the heat-dissipating structure 1b is obtained by deforming the heat conductive sheet 11 into a U shape.

As described above, in the heat radiating structures 1a and 1b, the rubber-like elastic bodies 12a and 12 are divided in the thickness direction in the inner space formed by bending or bending the heat conductive sheet 11, and the heat is conducted. It is possible to follow when the bending or bending of the sheet 11 is opened and flattened.

(Fourth Embodiment)
Next, a fourth embodiment of the present invention will be described. In the fourth embodiment, the parts common to each of the above embodiments including the first embodiment are designated by the same reference numerals, and duplicate description will be omitted. The fourth embodiment shows a modified example of the heat radiating structure of the first embodiment.

FIG. 5 shows a cross-sectional view of the heat radiating structure according to the fourth embodiment, which is the same as (1C). FIG. 6 shows each cross-sectional view before and after the curved deformation of the modified example of the heat radiating structure according to the fourth embodiment.

The heat radiating structure 1c according to the fourth embodiment includes one rubber sheet 13c over both ends of the heat conductive sheet 11 on the outer surface when the heat conductive sheet 11 is curved and deformed. This structure is different from the structure in which the rubber sheets 13 and 13 are divided and provided as in the heat radiating structure 1 according to the first embodiment. Except for the configuration of the rubber sheet 13c in the heat radiating structure 1c, it is common to the heat radiating structure 1.

Further, in addition to forming the rubber sheet 13c on the outer surface from one end to the other end of the heat conductive sheet 11, as in the heat radiating structure 1d according to the modified example shown in FIG. 6, rubber By forming a notch 40 that divides the thickness direction of the elastic body 12a, a flat plate-shaped heat radiating structure 1d in which the rubber elastic body 12a, the heat conductive sheet 11, and the rubber sheet 13c are laminated in this order can be manufactured. The heat radiating structure 1d is formed by deforming the heat conductive sheet 11 into a U shape by bending and deforming the heat conductive structure 1d so as to bend from a substantially central portion in the length direction (horizontal direction in the drawing) toward the rubber-like elastic body 12a. It becomes the heat dissipation structure 1d of.

(Fifth Embodiment)
Next, a fifth embodiment of the present invention will be described. In the fifth embodiment, the parts common to each of the above embodiments including the first embodiment are designated by the same reference numerals, and duplicate description will be omitted. The fifth embodiment shows a modified example of the heat radiating structure of the first embodiment.

FIG. 7 shows a cross-sectional view (7A) of the heat radiating structure according to the fifth embodiment and the same as (1C), and each cross-sectional view (7B) before and after fixing the battery cell in the cross-sectional view.

The heat radiating structure 1e according to the fifth embodiment has a heat conductive sheet 11e having two U-shaped curved portions. The heat conductive sheet 11e has a substantially S-shaped shape in a cross section in the same view as (1C). In this way, by using the heat conductive sheet 11e having a substantially S-shaped cross section when cut in the direction from the end of the heat conductive sheet toward the first curved portion, the cushion material between the heat source and the cooling member can also be used. Can demonstrate the function as. In this embodiment, one rubber-like elastic body 12 is arranged for each inner space formed by bending or bending the heat conductive sheet 11e. However, the rubber-like elastic body 12 may be arranged only in one inner space of the heat conductive sheet 11e. The rubber sheets 13 and 13 are formed on one surface at both ends of the heat conductive sheet 11e and on a surface different from the arrangement surface of the rubber-like elastic body 12. This point is the same as that of the first embodiment.

As shown in FIG. 7B, in the heat radiating structure 1e, one rubber sheet 13 is attached to the bottom 24 of the battery 20 which is an example of a cooling member, and the other rubber sheet 13 is an example of a heat source battery cell 21. It can be installed in the battery 20 so as to come into contact with each other. The heat radiating structure 1e is compressed by receiving the load of the battery cell 21. Further, the rubber sheet 13 on the battery cell 21 side embeds the battery cell 21. In this embodiment, a large number of battery cells 21 are lined up in the front and back directions of the paper surface of FIG. 7 (7B). The rubber sheet 13 on the battery cell 21 side is in close contact with both the battery cell 21 and the heat conductive sheet 11e so as not to reduce the heat transfer efficiency to the heat conductive sheet 11e even if there are steps in a large number of battery cells 21.

(Action / effect of each embodiment)
As described above, the heat radiating structures 1, 1a, 1b, 1c, 1d, 1e (hereinafter referred to as "heat radiating structure 1 and the like") are the heat sources such as the battery cell 21 and the circuit board 33, and the battery 20. A heat-dissipating structure between the bottom portion 24 (a part of the housing 22) and a cooling member such as a heat sink 32 for conducting heat from the heat source to the cooling member, and is at least metal, carbon, or ceramics. The heat conductive sheets 11 and 11e, which are composed of one and are arranged by being curved or bent between the heat source and the cooling member, and the inner side formed by the bending or bending of the heat conductive sheets 11, 11e. Rubber sheets 12, 12a arranged at least in the space, rubber sheets 13, 13c for closely fixing the heat conductive sheets 11, 11e and the heat source, heat conductive sheets 11, 11e, rubber sheets 13, It is provided with energizing electrodes 14, 14 capable of supplying power to heat the 13c or the rubber-like elastic bodies 12, 12a.

When the heat radiating structure 1 and the like are configured as described above, it is possible to realize the heat radiating structure 1 and the like having excellent heat radiating efficiency and a heat generating function, and the battery 20 and the electronic device 30 provided with the heat radiating structure 1 and the like. Even when the ambient temperature drops and the electronic components of each battery cell 21 of the battery 20 and the electronic device 30 do not function normally, a current is passed between the energizing electrodes 14 and 14 to pass the heat conductive sheets 11 and 11e. By heating the rubber sheets 13, 13c or the rubber-like elastic bodies 12, 12a, the functions of the battery cells 21 and the electronic components can be normally exhibited.

Since the heat conductive sheets 11 and 11e have one or more U-shaped curved portions or V-shaped bent portions, avoiding the thickness direction of the heat radiating structure 1 and the like, and along the heat conductive sheets 11 and 11e. Easy to transfer heat. The heat conductive sheets 11 and 11e are arranged in the heat radiating structure 1 and the like in a U-shaped or V-shaped winding shape in the gap between the heat source and the cooling member. Therefore, the heat conductive sheets 11 and 11e are less likely to be damaged by the load from the heat source. Further, the rubber-like elastic bodies 12 and 12a contribute to enhancing the cushioning property of the heat radiating structure 1 and the like.

The rubber-like elastic bodies 12 and 12a in the third embodiment and the fourth embodiment are divided in the thickness direction of the inner space, and when the heat conductive sheet 11 is flattened by opening the curvature or bending. Can be followed. Therefore, by manufacturing the heat radiating structure 1 or the like into a flat plate shape and bending it from substantially the center in the length direction, the heat conductive sheet 11 having one or more U-shaped curved portions or V-shaped bent portions can be obtained. It can be easily formed.

By using the heat conductive sheets 11 and 11e as carbon sheets, it becomes easy to manufacture the heat conductive sheets 11 and 11e having one or more curved portions or bent portions. In particular, by using a carbon sheet as a sheet containing carbon fibers and a resin, it is possible to easily form a sheet that is highly flexible and easily curved or bent. Further, by forming the energizing electrodes 14 and 14 into a silver thin film formed on the heat conductive sheets 11 and 11e, the electric resistance of the energizing electrodes 14 and 14 can be reduced, and the electrodes can be easily formed.

By using the rubber sheets 13 and 13 as sheets made of silicone rubber, it becomes easy to produce sheets having high thermal conductivity and low hardness and capable of absorbing the unevenness of the heat source. Further, the rubber sheets 13 and 13 are not melted by the heat from the heat source and are not easily damaged.

One of the above-mentioned heat dissipation structures 1 and the like is arranged between the battery cell 21 as a heat source and the housing 22 (bottom 24 in the above embodiment) as a cooling member in which the battery cell 21 is arranged. When the battery 20 is configured, it is possible to realize the battery 20 in which the battery cell 21 does not easily deteriorate the functions of power generation and charging due to high temperature (60 ° C. or higher) or low temperature (0 ° C. or lower).

(Other embodiments)
As described above, the preferred embodiments of the present invention have been described, but the present invention is not limited to these, and can be implemented in various modifications.

For example, the heat source includes not only the battery cell 21 and the circuit board 33 but also all the objects that generate heat. As the heat source, for example, electronic components such as a capacitor 34 and an IC chip 35 may be targeted. Similarly, the cooling member includes not only the bottom portion 24 and the heat sink 32, but also all the members that release heat from the heat source.

In each of the above-described embodiments, the rubber-like elastic bodies 12 and 12a are arranged only in the inner space formed by bending or bending the heat conductive sheets 11 and 11e, but not only in the inner space but also in the inner space. It may be formed so as to extend beyond the inner space. For example, the rubber-like elastic bodies 12 and 12a may wrap around to the rubber sheets 13 and 13c and come into close contact with the heat conductive sheets 11 and 11e.

The rubber sheets 13 and 13c do not have to exist between the heat conductive sheets 11 and 11e and the cooling member as long as they exist between the heat conductive sheets 11 and 11e and the heat source. Further, the rubber sheets 13 and 13c may be in contact with or in close contact with each other without being adhered to the heat source or the cooling member, and may be easily attached to or detached from the heat source or the cooling member. The heat conductive sheet may have a V-shaped cross section or a U-shaped cross section instead of the embodiment described in each of the above embodiments.

Further, the plurality of components of each of the above-described embodiments can be freely combined except when they cannot be combined with each other. For example, in the second embodiment, the electronic device 20 is equipped with the heat radiating structures 1a, 1b, 1c. Either 1d or 1e may be provided. Further, the cuts 40 and 41 may be adopted in the heat radiating structure 1e according to the fifth embodiment.

The heat radiating structure according to the present invention can be used not only for automobile batteries but also for various electronic devices such as automobiles, industrial robots, power generation devices, PCs, and household electric appliances.

1,1a, 1b, 1c, 1d, 1e ... Heat dissipation structure, 11,11e ... Heat conductive sheet (carbon sheet, sheet containing carbon fiber and resin), 12, 12a ... Rubber Elastic body, 12b ... 1st rubber elastic body, 12c ... 2nd rubber elastic body, 13, 13c ... rubber sheet (silicone rubber sheet), 14 ... energizing electrode ( (Silver thin film), 20 ... Battery, 21 ... Battery cell (an example of heat source), 22 ... Housing (including cooling member), 23 ... Inner bottom surface, 24 ... Bottom (cooling member) (Example), 30 ... Electronic equipment, 31 ... Housing, 32 ... Heat sink (example of cooling member), 33 ... Circuit board (example of heat source).

Claims (6)

A heat radiating structure between a heat source and a cooling member for conducting heat from the heat source to the cooling member.
A heat conductive sheet made of at least one of metal, carbon or ceramic and arranged to be curved or bent between the heat source and the cooling member.
A rubber-like elastic body that is at least arranged in the inner space formed by bending or bending the heat conductive sheet, and
A rubber sheet for closely fixing the heat conductive sheet and the heat source,
The heat conductive sheet, the rubber sheet, or the energizing electrode capable of supplying power for heating the rubber-like elastic body,
Equipped with a,
The rubber-like elastic body is divided in the thickness direction of the inner space, and is a heat radiating structure that can follow when the heat conductive sheet is flattened by opening the curvature or bending. The heat radiating structure according to claim 1, wherein the heat conductive sheet has one or more U-shaped curved portions or V-shaped bent portions. The heat conductive sheet is made of carbon and is used as a carbon sheet.
The heat radiating structure according to claim 1 or 2 , wherein the current-carrying electrode is a silver thin film formed on the heat conductive sheet. The heat radiating structure according to claim 3 , wherein the carbon sheet is a sheet containing carbon fibers and a resin. The heat radiating structure according to any one of claims 1 to 4 , wherein the rubber sheet is a sheet made of silicone rubber. A battery in which the heat radiating structure according to any one of claims 1 to 5 is arranged between a battery cell as a heat source and a housing as a cooling member in which the battery cell is arranged.

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