JP2020113393A - Heat dissipation structure and battery with it - Google Patents

Abstract

To provide a lightweight heat dissipation structure adaptable to various types of heat source, excellent in heat dissipation efficiency and elastic deformability, and capable of restraining damage due to pressure from a heat source, and to provide the heat dissipation structure.SOLUTION: In heat dissipation structure 25 of a battery 1 coupled with multiple heat dissipation members 28 for improving heat dissipation from a heat source 20, the heat dissipation member 28 includes a heat conductive sheet of such a shape as progressing while winding spirally for conducting heat from the heat source 20, a cushion member provided on the annular reverse face of the heat conductive sheet, and deformable easily according to the surface shape of the heat source 20 compared with the heat conductive sheet, and a penetration passage penetrating in the direction of the heat conductive sheet progressing while winding. The cushion member has uneven thickness, and the multiple heat dissipation members 28 are coupled by coupling members while being arranged in a direction orthogonal to the direction of the heat conductive sheet progressing while winding.SELECTED DRAWING: Figure 2

Description

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

Control systems for automobiles, aircrafts, ships, or household or commercial electronic devices have become more precise and complicated, and along with this, the integration density of small electronic components on a circuit board has been 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.

To realize rapid heat dissipation from a circuit board, conventionally, the circuit board itself is made of a material having excellent heat dissipation, a heat sink is attached, or a means for driving a heat dissipation fan is used alone or in combination. Has been done. Among these, the method of forming the circuit board itself from a material having excellent heat dissipation, such as diamond, aluminum nitride (AlN), and cubic boron nitride (cBN), results in extremely high cost of the circuit board. Further, the arrangement of the heat radiation fan causes a problem that the fan, which is a rotating device, fails, needs maintenance for preventing the failure, and has difficulty in securing an installation space. On the other hand, the radiating fin has a large number of columnar or flat plate-shaped protruding portions made of a metal having high thermal conductivity (for example, aluminum), and thus has a large surface area and can further improve the heat radiating property. Since it is such a member, it is widely used as a heat dissipation component (see Patent Document 1).

By the way, nowadays, there is an increasing trend in the world to gradually convert conventional gasoline or diesel vehicles into electric vehicles in order to reduce the load on the global environment. In particular, European countries such as France, the Netherlands and Germany, as well as China, have declared that they will completely switch from gasoline and diesel vehicles to electric vehicles by 2040. The spread of electric vehicles requires the development of high-performance batteries and the installation of many charging stands. In particular, technological development for enhancing the charge/discharge function of lithium-based automobile batteries is important. It is well known that the above-mentioned automobile battery cannot fully exhibit the charge/discharge function at a high temperature of 60° C. or higher. For this reason, it is important to improve heat dissipation in the battery as in the circuit board described above.

To realize rapid heat dissipation from the battery, place a water-cooling 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 cells and the bottom surface of the housing. Adhesive rubber sheet is sandwiched between and. In the battery having such a structure, the battery cell transfers heat to the housing through the rubber sheet and is effectively removed by water cooling.

Japanese Patent Laid-Open No. 2008-243999

However, in the conventional battery as described above, since the rubber sheet has lower thermal conductivity than aluminum or graphite, it is difficult to efficiently transfer heat from the battery cell to the housing. A method of sandwiching a spacer such as graphite instead of the rubber sheet may be considered, but since the lower surfaces of the plurality of battery cells are not flat and have steps, a gap is created between the battery cells and the spacer, and heat transfer efficiency is improved. descend. As seen in such an example, since the battery cell can take various forms (including unevenness such as steps or surface state), it is possible to adapt to various forms of the battery cell and realize high heat transfer efficiency. Are increasing in demand. Furthermore, there is a demand for lighter weight and elastic deformation of the material of the battery cell container, and a heat dissipation structure that returns to a shape close to the original shape when the battery cell is lightened or the battery cell is removed is desired. ing. Therefore, a method of wrapping a highly heat-conductive sheet such as graphite around the outer surface of the tubular cushion member formed of rubber or the like can be considered, but when the heat dissipation structure is crushed by the pressure from the battery cells, The stress of the cushion member may cause cracks in the sheet, and it is also desired to suppress damage to the heat dissipation structure due to pressing from the battery cells. This goes not only to the battery cells, but also to other heat sources such as circuit boards, electronic components or the body of the electronic device.

The present invention has been made in view of the above problems, is adaptable to various forms of a heat source, is lightweight, has excellent heat dissipation efficiency, is highly elastically deformable, and suppresses damage due to pressing from the heat source. An object is to provide a possible heat dissipation structure and a battery including the heat dissipation structure.

(1) A heat dissipation structure according to an embodiment for achieving the above object is a heat dissipation structure in which a plurality of heat dissipation members that enhance heat dissipation from a heat source are connected, and the heat dissipation member is provided from the heat source. A heat-conducting sheet having a shape that advances in a spiral shape for transmitting heat, and a cushion that is provided on the annular back surface of the heat-conducting sheet and that is easier to deform in accordance with the surface shape of the heat source than the heat-conducting sheet. A member and a through-passage that penetrates in a direction in which the heat-conducting sheet advances while being wound, the cushion member has an uneven thickness, and the plurality of heat-dissipating members are the heat-conducting sheets. Are connected by a connecting member in a state of being lined up in a direction orthogonal to the direction of movement while winding.
(2) In the heat dissipation structure according to another embodiment, preferably, the cushion member has one or more recesses that are recessed toward the heat conductive sheet, on the surface opposite to the heat conductive sheet.
(3) In the heat dissipation structure according to another embodiment, preferably, the cushion member has concavities and convexities that are continuous at predetermined intervals on the surface opposite to the heat conductive sheet.
(4) In the heat dissipation structure according to another embodiment, preferably, the cushion member is a tubular cushion member having the through passage in its length direction, and the heat conductive sheet is the tubular cushion. The outer surface of the member is spirally wound.
(5) In the heat dissipation structure according to another embodiment, preferably, the cushion member is a spiral cushion member that is spirally wound along the annular back surface of the heat conductive sheet.
(6) In the heat dissipation structure according to another embodiment, preferably, the connecting member is made of a yarn, and a twisted portion in which a twist is added is provided between the plurality of heat dissipation members. The heat radiating member is connected by the thread in a direction orthogonal to the direction in which the heat conducting sheet advances while being wound.
(7) In the heat dissipation structure according to another embodiment, preferably, the plurality of heat dissipation members are arranged at a distance of 0.114 times or more the circle equivalent diameter of the heat dissipation members.
(8) In the heat dissipation structure according to another embodiment, preferably, the surface of the heat conductive sheet has a heat conductive oil for increasing heat conductivity from a heat source in contact with the surface to the surface.
(9) In the heat dissipation structure according to another embodiment, preferably, the heat conductive oil has heat conductivity higher than that of silicone oil and the silicone oil, and is made of one or more of metal, ceramics or carbon. With a hydrophilic filler.
(10) A battery according to an embodiment is a battery including one or more battery cells as a heat source in a casing having a structure for flowing a cooling member, and between the battery cell and the casing. And the heat dissipation structure according to any one of the above.

ADVANTAGE OF THE INVENTION According to this invention, it is adaptable to various forms of a heat source, is lightweight, is excellent in heat dissipation efficiency, is rich in elastic deformability, and can suppress damage due to pressure from the heat source, and the heat dissipation structure. A battery including the structure can be provided.

FIG. 1 is a plan view (1A) of the heat dissipation structure according to the first embodiment, a sectional view (1B) taken along the line AA in (1A), and an enlarged view (1C) of a region B in the sectional view. Shown respectively. FIG. 2 is a longitudinal cross-sectional view (2A) of the heat dissipation structure according to the first embodiment and a battery including the heat dissipation structure, and a heat dissipation structure before and after the heat dissipation structure is compressed by the battery cells in (2A). Sectional drawing (2B) of a form change is shown, respectively. FIG. 3 is a diagram for explaining a part of the method of manufacturing the heat dissipation structure of FIG. 1. FIG. 4 shows a partially enlarged view (4A) of the heat dissipation structure according to the second embodiment and a partially enlarged view (4B) of the heat dissipation structure according to the third embodiment. FIG. 5 is a plan view (5A) of the heat dissipation structure according to the fourth embodiment, a sectional view (5B) taken along the line C-C in (5A), and an enlarged view (5C) of a region D in the sectional view. Shown respectively. FIG. 6 is a vertical cross-sectional view (6A) of a heat dissipation structure according to the fourth embodiment and a battery including the heat dissipation structure, and a heat dissipation structure before and after the heat dissipation structure is compressed by the battery cells in (6A). Sectional drawing (6B) of a form change is shown, respectively. FIG. 7 is a vertical cross-sectional view of a heat dissipation structure according to the fifth embodiment and a battery including the heat dissipation structure. FIG. 8 shows a part (8A) of a manufacturing state of the heat dissipation structure of FIG. 7 and a plan view (8B) of the heat dissipation structure completed by the manufacturing method of (8A). FIG. 9 shows a cross-sectional view of a battery cell placed laterally on the heat dissipation structure so that the side surfaces of the battery cell are in contact with each other, a partially enlarged view of the battery cell, and a partial cross-sectional view of the battery cell when expanded during charging and discharging. Shown respectively.

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

(First embodiment)
FIG. 1 is a plan view (1A) of the heat dissipation structure according to the first embodiment, a sectional view (1B) taken along the line AA in (1A), and an enlarged view (1C) of a region B in the sectional view. Shown respectively. FIG. 2 is a longitudinal cross-sectional view (2A) of the heat dissipation structure according to the first embodiment and a battery including the heat dissipation structure, and a heat dissipation structure before and after the heat dissipation structure is compressed by the battery cells in (2A). Sectional drawing (2B) of a form change is shown, respectively.

As shown in FIG. 2, the battery 1 has a structure in which a plurality of battery cells 20 are provided in a housing 11 that contacts the cooling member 15. The heat dissipation structure 25 is preferably an end portion (lower end portion) of the battery cell 20, which is an example of a heat source, closer to the cooling member 15 and a part (bottom portion 12) of the housing 11 closer to the cooling member 15. It is equipped between. Here, 11 battery cells 20 are placed on the heat dissipation structure 25, but the number of battery cells 20 placed on the heat dissipation structure 25 is not limited to 11. In addition, the number of heat dissipation members 28 that form the heat dissipation structure 25 provided in the battery 1 is not particularly limited.

The heat dissipation structure 25 is a structure in which a plurality of heat dissipation members 28 that enhance heat dissipation from the battery cells 20 are connected. The heat radiating member 28 is provided on the heat conducting sheet 30 in a spiral shape for transmitting heat from the battery cells 20, and on the annular back surface of the heat conducting sheet 30. A cushion member 31 that is easily deformable according to the surface shape of the cell 20 and a through passage 32 that penetrates in the direction in which the heat conduction sheet 30 advances while being wound are provided. The cushion member 31 has a nonuniform thickness. Further, the plurality of heat dissipation members 28 are connected by the connecting member 35 in a state of being aligned in a direction orthogonal to the direction in which the heat conducting sheet 30 advances while being wound. Here, the heat conductive sheet 30 is preferably made of a material having higher heat conductivity than the cushion member 31. The cushion member 31 preferably has one or more recesses 40 recessed toward the heat conductive sheet 30 on the surface opposite to the heat conductive sheet 30, and more preferably has continuous irregularities at predetermined intervals. Further, the cushion member 31 is preferably a tubular cushion member having a through passage 32 in the length direction thereof. The heat conductive sheet 30 is formed by spirally winding the outer surface of the tubular cushion member. Further, the heat dissipation structure 25 preferably has a heat conductive oil on the surface and/or inside of the heat conductive sheet 30 for increasing the heat conductivity from the battery cells 20 in contact with the surface to the surface. .. The plurality of heat dissipating members 28 constituting the heat dissipating structure 25 have a substantially cylindrical shape when the battery cells 20 are not mounted, but when the battery cells 20 are mounted, they are compressed and flattened by their weight. Take the form.

The heat-conducting sheet 30 is a strip-shaped sheet that advances in the substantially cylindrical length direction while spirally winding the outer surface of the heat dissipation member 28. The heat conductive sheet 30 is a sheet containing at least one of metal, carbon, and ceramics, and has a function of conducting heat from the battery cells 20 to the cooling member 15. In the present application, the “cross section” or the “vertical cross section” means a cross section in the direction perpendicular to the upper opening surface in the inside 14 of the housing 11 of the battery 1 to the bottom portion 12.

Next, the schematic configuration of the battery 1 and the constituent members of the heat dissipation structure 25 will be described in more detail.

(1) Outline of Battery Configuration In this embodiment, the battery 1 is, for example, a battery for an electric vehicle and includes a large number of battery cells (may be simply referred to as cells) 20. The battery 1 preferably includes a bottomed housing 11 that is open to one side. The housing 11 is preferably made of aluminum or an aluminum-based alloy. The battery cell 20 is arranged in the inside 14 of the housing 11. An electrode (not shown) is provided so as to project above the battery cell 20. The plurality of battery cells 20 are preferably brought into close contact with each other in the housing 11 by being applied with a force from both sides in a direction of compression using screws or the like (not shown). The bottom portion 12 of the housing 11 is provided with one or a plurality of water cooling pipes 13 for flowing cooling water, which is an example of the cooling member 15. The cooling member may be referred to as a cooling medium or a coolant. The battery cell 20 is arranged in the housing 11 so that the heat dissipation structure 25 is sandwiched between the battery cell 20 and the bottom portion 12. In the battery 1 having such a structure, the battery cell 20 transfers heat to the housing 11 through the heat dissipation structure 25 and is effectively removed by water cooling. It should be noted that the cooling member 15 is not limited to cooling water, but is also interpreted to include liquid nitrogen, an organic solvent such as ethanol, or the like. The cooling member 15 is not limited to a liquid under the condition of being used for cooling, but may be a gas or a solid.

(2) Heat Conduction Sheet The heat conduction sheet 30 is preferably a sheet containing carbon, and more preferably a sheet containing carbon filler and resin. The resin may be synthetic fiber, and in that case, aramid fiber may be preferably used. The "carbon" in the present application includes any structure having carbon (elemental symbol: C) such as graphite, carbon black having a lower crystallinity than graphite, expanded graphite, diamond, and diamond-like carbon having a structure similar to diamond. Is interpreted broadly. In this embodiment, the heat conductive sheet 30 can be a thin sheet obtained by curing a material in which graphite fibers and carbon particles are mixed and dispersed in resin. The heat conductive sheet 30 may be a carbon fiber knitted in a mesh shape, and further may be mixed-spun or mixed-knitted. Note that various fillers such as graphite fibers, carbon particles, or carbon fibers are all included in the concept of carbon filler.

When the heat-conducting sheet 30 contains a resin, the amount of the resin may be more than 50 mass% or less than 50 mass% with respect to the total mass of the heat-conducting sheet 30. That is, the heat conductive sheet 30 may or may not be made of resin as a main material as long as it does not significantly affect heat conduction. As the resin, for example, a thermoplastic resin can be preferably used. The thermoplastic resin is preferably a resin having a high melting point such that it does not melt when conducting heat from the battery cell 20, which is an example of a heat source, and examples thereof include polyphenylene sulfide (PPS) and polyether ether ketone (PEEK). Preferable examples include polyamide imide (PAI) and aromatic polyamide (aramid fiber). The resin is dispersed, for example, in the form of particles or fibers in the gaps between the carbon fillers before the heat conductive sheet 30 is molded. The heat conductive sheet 30 may have AlN or diamond dispersed therein as a filler for enhancing heat conduction, in addition to the carbon filler and the resin. Further, instead of the resin, an elastomer softer than the resin may be used. The heat conductive sheet 30 can also be a sheet containing metal and/or ceramics instead of or together with carbon as described above. As the metal, one having relatively high thermal conductivity such as aluminum, copper, or an alloy containing at least one of them can be selected. Further, as the ceramics, AlN, cBN, hBN or the like having relatively high thermal conductivity can be selected.

It does not matter whether the heat conductive sheet 30 has excellent conductivity. The thermal conductivity of the thermal conductive sheet 30 is preferably 10 W/mK or more. In this embodiment, the heat-conducting sheet 30 is preferably a graphite strip-shaped plate, and is made of a material having excellent thermal conductivity and electrical conductivity. The heat conductive sheet 30 is preferably a sheet having excellent bendability (or flexibility), and the thickness thereof is not limited, but 0.02 to 3 mm is preferable, and 0.03 to 0.5 mm is more preferable. However, since the thermal conductivity of the thermal conductive sheet 30 decreases as the thickness thereof increases, it is necessary to determine the thickness by comprehensively considering the strength, flexibility and thermal conductivity of the sheet. preferable.

(3) Cushion member The important functions of the cushion member 31 are easiness of deformation and resilience. The resilience is due to elastic deformability. Deformability is a characteristic required to follow the shape of the battery cell 20, and in particular, a semi-solid material such as a lithium-ion battery or a content having a liquid property is contained in a package that is easily deformed. In the case of the battery cell 20, it is often the case that the amorphous shape or the dimensional accuracy cannot be improved in terms of design dimensions. For this reason, it is important to retain the resilience for retaining the deformability and the follow-up force of the cushion member 31.

The cushion member 31 is a tubular cushion member having a through passage 32 in this embodiment. The cushion member 31 has a non-uniform thickness, and preferably has one or more recesses 40 recessed toward the heat conductive sheet 30 on the surface opposite to the heat conductive sheet 30. Further, more preferably, the cushion member 31 has concavities and convexities that are continuous at a predetermined interval on the surface opposite to the heat conductive sheet 30. As for the unevenness of the cushion member 31, preferably, the concave portion 40 and the convex portion 41 each have a substantially V shape in a cross-sectional view taken along the line AA of FIG. 1, and the concave portion 40 and the convex portion 41 are continuous. It has a saw blade shape. The recess 40 is a groove that is long in the length direction of the cushion member 31. Further, the through passage 32 has the unevenness on the outer peripheral surface thereof according to the unevenness of the cushion member 31. The cushion member 31 makes good contact between the heat conduction sheet 30 and the lower end portions even when the lower end portions of the plurality of battery cells 20 are not flat. Further, the through passage 32 has a function of facilitating the deformation of the cushion member 31, contributing to the weight reduction of the heat dissipation structure 25, and enhancing the contact between the heat conduction sheet 30 and the lower end portion of the battery cell 20. .. The cushion member 31 has a function between the battery cell 20 and the bottom portion 12 to exert cushioning properties, and also has a function as a protection member for preventing the heat conducting sheet 30 from being damaged by a load applied to the heat conducting sheet 30. Have. The cushion member 31 is elastically deformed more easily than the heat conductive sheet 30, and is less likely to be cracked or cracked due to the pressure applied from the battery cell 20 and the deformation caused by the opening. In particular, the cushion member 31 is provided with the concave portion 40 on the surface opposite to the heat conductive sheet 30, so that the stress of the cushion member 31 generated when the heat dissipation structure 25 is crushed due to the pressure from the battery cell 20 is reduced. Therefore, it is possible to prevent the heat conductive sheet 30 from being cracked. Therefore, damage to the heat dissipation structure 25 due to the pressure from the battery cells 20 can be suppressed. In addition, in this embodiment, the cushion member 31 is a member having a lower thermal conductivity than the thermal conductive sheet 30. Further, the number and position of the irregularities formed on the surface of the cushion member 31 opposite to the heat conductive sheet 3 (the surface on the side of the through passage 32) are not particularly limited. The recess 40 may be a dot-shaped hole instead of the groove.

The cushion member 31 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); urethane type , An ester-based, a styrene-based, an olefin-based, a butadiene-based, a fluorine-based thermoplastic elastomer, a composite thereof, or the like. The cushion member 31 is preferably made of a material having high heat resistance such that the cushion member 31 can maintain its shape without being melted or decomposed by heat transmitted through the heat conductive sheet 30. In this embodiment, the cushion member 31 is more preferably made of a urethane-based elastomer impregnated with silicone or a silicone rubber. The cushion member 31 may be configured by dispersing fillers represented by AlN, cBN, hBN, diamond particles, or the like in rubber in order to enhance the thermal conductivity of the cushion member 31. The cushion member 31 may not contain bubbles in addition to the one containing bubbles therein. Further, the “cushion member” means a member that is highly flexible and elastically deformable so as to be in close contact with the surface of the heat source, and can be read as “rubber-like elastic body” in this sense. Further, as a modified example of the cushion member 31, a metal may be used instead of the rubber-like elastic body. The cushion member 31 may be made of sponge or solid (having a non-porous structure such as sponge) formed of resin, rubber, or the like.

(4) Connecting Member The connecting member 35 is a member made of a material such as a thread or a rubber that is located between at least a plurality of heat dissipating members 28 and is deformable. In the present embodiment, the connecting member 35 is preferably made of a thread, and more preferably a thread that can withstand a temperature rise due to heat radiation from the battery cells 20. More specifically, the connecting member 35 is a yarn that can withstand a high temperature of about 120° C., and is preferably configured by a twisted yarn made of fibers such as natural fibers, synthetic fibers, carbon fibers, and metal fibers. In addition, the connecting member 35 preferably includes a twisted portion 37 in which a twist is added between the plurality of heat dissipation members 28 (see FIG. 1C). In the heat dissipation structure 25, even if the heat dissipation member 28 is compressed and flattened by the battery cell 20, the connecting member 35 bends following the deformation of the heat dissipation member 28, so that the heat dissipation member 28 follows and adheres to the surface of the battery cell 20. can do. Further, the heat dissipation structure 25 is provided with the twisted portion 37 between the plurality of heat dissipation members 28, so that it is possible to further improve the followability and adhesion to the surface of the battery cell 20. The connecting member 35 does not necessarily have to have the twisted portion 37.

The gap L1 between the heat dissipating members 28 becomes narrower when the heat dissipating member 28 receives pressure from the battery cells 20 and collapses. When the heat dissipation member 28 is hardly crushed, the adhesion between the heat conductive sheet 30 and the battery cell 20 and the bottom 12 may be low. The thickness of the heat dissipation member 28 suitable for reducing such a risk is at least the pipe diameter of the heat dissipation member 28 (= the thickness when compressed in the vertical direction from the bottom of the battery cell 20 to the surface of the bottom portion 12). It is 80% of the circle equivalent diameter: D). Here, the “circle-converted diameter” means the diameter of a perfect circle having the same area as the area of the cross section of the pipe when the heat dissipation member 28 is cut perpendicularly to its length direction. When the heat radiating member 28 is a cylinder having a perfect circular cross section, its diameter is the same as the circle equivalent diameter. When the heat dissipation member 28 receives the above compression, it can be regarded that it deforms so that the surface in contact with the battery cell 20 and the bottom portion 12 is a flat surface and the direction of the gap L1 between the heat dissipation members 28 is a substantially arc cross section (FIG. 1 (see 1C)). When the heat dissipation member 28 is crushed to a thickness of 0.8D corresponding to 80% of the circle-converted diameter D, how much the heat dissipation member 28 expands in the direction of the gap L1 is calculated. As shown in FIG. 1(1C), in the crushed heat dissipation member 28, the total length of the semi-circular arcs existing in the left-right direction is 0.8πD. Further, the length of the plane in contact with the bottom portion 12 is half the length obtained by subtracting the total length of the above semicircular arcs from the tube circumference of the heat dissipation member 28, so (πD−0.8πD)/2. = 0.314D. The length of the arc portion expanded in the horizontal direction of the plane is 0.4D×2=0.8D. Therefore, the distance that the crushed heat dissipation member 28 spreads from the original heat dissipation member 28 in the direction of the gap L1 is 0.314D+0.8D−D=0.114D. If the gap L1 is made sufficiently large, the heat dissipation member 28 does not contact the adjacent heat dissipation member 28. On the contrary, if the gap L1 is too small, even if the heat radiating member 28 is compressed in the vertical direction, it may come into contact with the adjacent heat radiating member 28 and may not be further crushed. If the gap L1 is set to 11.4% or more of the circle-converted diameter D of the heat-dissipating member 28, the heat-dissipating members 28 come into contact with each other when the heat-dissipating member 28 is compressed and deformed to a thickness of 80% of the circle-converted diameter D. As a result, it is possible to prevent the deformation from becoming an obstacle. In this embodiment, the gap L1 is 0.6D.

(5) Thermally Conductive Oil The thermally conductive oil preferably contains silicone oil and a thermally conductive filler having higher thermal conductivity than silicone oil and made of one or more of metal, ceramics or carbon. Microscopically, the heat conductive sheet 30 has a gap (hole or recess). Air is usually present in the gap, which may adversely affect the thermal conductivity. The heat conductive oil fills the gap and exists instead of air, and has a function of improving the heat conductivity of the heat conductive sheet 30.

The heat conductive oil is provided on the surface of the heat conductive sheet 30, at least the surface where the battery cells 2 and the heat conductive sheet 30 are in contact with each other. In the present application, the “oil” of the heat conductive oil refers to a non-water-soluble liquid or semi-solid flammable substance at room temperature (any temperature in the range of 20 to 25° C.). Instead of the word "oil", "grease" or "wax" can be used. The heat-conducting oil is an oil that does not obstruct heat conduction when transferring heat from the battery cells 20 to the heat-conducting sheet 30. Hydrocarbon-based oil or silicone oil can be used as the heat conductive oil. The thermally conductive oil preferably contains silicone oil and a thermally conductive filler having higher thermal conductivity than silicone oil and made of one or more of metal, ceramics or carbon.

The silicone oil preferably consists of a molecule having a linear structure with 2000 or less siloxane bonds. Silicone oils are roughly classified into straight silicone oils and modified silicone oils. Examples of the straight silicone oil include dimethyl silicone oil, methylphenyl silicone oil and methylhydrogen silicone oil. Examples of the modified silicone oil include reactive silicone oil and non-reactive silicone oil. The reactive silicone oil includes various silicone oils such as amino-modified type, epoxy-modified type, carboxy-modified type, carbinol-modified type, methacryl-modified type, mercapto-modified type and phenol-modified type. The non-reactive silicone oil includes various silicone oils such as polyether modified type, methylstyryl modified type, alkyl modified type, higher fatty acid ester modified type, hydrophilic special modified type, higher fatty acid containing type and fluorine modified type. Since silicone oil is an oil having excellent heat resistance, cold resistance, viscosity stability, and thermal conductivity, it is applied on the surface of the thermal conductive sheet 30 and is interposed between the battery cell 20 and the thermal conductive sheet 30. It is particularly suitable as a heat conductive oil.

The thermally conductive oil preferably contains, in addition to the oil component, a thermally conductive filler made of one or more of metal, ceramics or carbon. Examples of the metal include gold, silver, copper, aluminum, beryllium, and tungsten. Examples of ceramics include alumina, aluminum nitride, cubic boron nitride, and hexagonal boron nitride. Examples of carbon include diamond, graphite, diamond-like carbon, amorphous carbon, and carbon nanotube.

The heat conductive oil is preferably interposed between the battery cell 2 and the heat conductive sheet 30 and also between the heat conductive sheet 30 and the housing 11. The heat conductive oil may be applied to the entire surface of the heat conductive sheet 30 or may be applied to a part of the heat conductive sheet 30. The method for allowing the heat conductive oil to be present in the heat conductive sheet 30 is not particularly limited, and spraying using a spray, application using a brush or the like, immersion of the heat conductive sheet 30 in the heat conductive oil, etc. Any method may be used. The heat conductive oil is not an essential component for the heat dissipation structure 25 or the battery 1, but is an additional component that can be suitably provided. This is the same in the second and subsequent embodiments.

FIG. 3 is a diagram for explaining a part of the method of manufacturing the heat dissipation structure of FIG. 1.

First, the cushion member 31 is formed. Next, the band-shaped heat conduction sheet 30 is spirally wound around the outer surface of the cushion member 31. At this time, in a non-hardened state where the cushion member 31 is not completely hardened, the heat conductive sheet 30 is wound around the outer surface of the cushion member 31, and then the cushion member 31 is completely hardened by heating. Then, if there is a portion protruding from both ends of the cushion member 31 of the band-shaped heat conductive sheet 30, it is cut. Finally, heat conductive oil is applied to the surface of the heat conductive sheet 30. By manufacturing the heat dissipation member 28 in this manner, the uncured cushion member 31 enters the microscopic gaps of the heat conductive sheet 30 and is cured. Therefore, the cushion member 31 does not require an adhesive agent or the like. 31 and the heat conductive sheet 30 can be firmly fixed.

The heat dissipation member 28 thus formed has a form protruding from the outer surface of the cushion member 31 by the thickness of the heat conductive sheet 30. However, the heat conduction sheet 30 and the cushion member 31 may be flush with each other. Further, the heat conductive oil may be applied to at least the surface of the heat conductive sheet 30 that is in contact with the battery cells 20. The step of cutting the portion of the heat conductive sheet 30 that protrudes from both ends of the cushion member 31 and the step of applying the heat conductive oil are not limited to being performed at the above-described timing, and at least the heat conductive sheet 30 should be provided on the cushion member 31. You can go anytime after winding. Further, the heat conductive sheet 30 may be wound around the outer surface of the cushion member 31 in a completely cured state. In this case, if the outer surface of the cushion member 31 is not tacky, the heat conductive sheet 30 may be fixed to the cushion member 31 using an adhesive or the like.

The heat dissipation structure 25 is formed by connecting the plurality of heat dissipation members 28 manufactured by the manufacturing method described above in a direction orthogonal to the direction in which the heat conduction sheet 30 advances while being wound, and connecting the heat dissipation sheets 28 with the connecting member 35. Manufactured. More specifically, the heat dissipation structure 25 is connected by sewn a thread by hand sewing with a plurality of heat dissipation members 28 arranged. At this time, the plurality of heat dissipation members 28 are preferably arranged with the gap L1 being 0.114D or more (see FIG. 1C). In addition, it is preferable to sew so that the twisted portion 37 is formed between the plurality of heat dissipation members 28. As described above, in the heat dissipation structure 25, since the plurality of heat dissipation members 28 are connected in a blind shape, the heat dissipation members 28 follow the surface of the battery cells 20 in the vertical and horizontal directions when compressed by the battery cells 20. When the battery cell 20 is removed, the elastic force of the heat dissipation member 28 allows the heat dissipation member 28 to return to its original shape. Further, in the heat dissipation structure 25, since the plurality of heat dissipation members 28 are connected in a blind shape, it is possible to suppress the situation where the heat dissipation members 28 are unevenly distributed due to, for example, vibration of an automobile, and the workability is improved. Further, the heat dissipation structure 25 has a structure in which each heat dissipation member 28 has the heat conduction sheet 30 wound in a spiral shape on the outer surface of the cushion member 31, and therefore does not restrain excessively against deformation of the cushion member 31. .. Further, since the cushion member 31 of the heat dissipation structure 25 has the recess 40 on the surface opposite to the heat conductive sheet 30, the heat dissipation structure 25 receives the pressure from the battery cells 20 and the heat dissipation structure 25 collapses. The stress can be reduced, and damage to the heat conductive sheet 30 can be suppressed.

(Second embodiment)
Next, a heat dissipation structure according to the second embodiment and a battery including the heat dissipation structure will be described. The same parts as those in the first embodiment are designated by the same reference numerals, and the duplicated description will be omitted.

FIG. 4 (4A) is a partially enlarged view of a cross-sectional view of the heat dissipation structure according to the second embodiment.

Unlike the heat dissipation structure 25 according to the first embodiment, the heat dissipation structure 25a according to the second embodiment has corrugated unevenness on the surface of the heat dissipation member 28a opposite to the heat conductive sheet 30 of the cushion member 31a. Has been formed. In addition, the through-passage 32a has corrugated irregularities on its outer peripheral surface according to the irregularities of the cushion member 31a. The configuration other than the cushion member 31a and the through passage 32a is the same as that of the first embodiment, and thus the description thereof is omitted.

The cushion member 31a has corrugated concavities and convexities continuous at predetermined intervals on the surface opposite to the heat conductive sheet 30, that is, the surface on the side of the through passage 32a. More specifically, in the cushion member 31a, a concave portion 40a that is depressed toward the heat conductive sheet 30 and a convex portion 41a that protrudes toward the through passage 32a are each formed in a U shape, and the concave portion 40a and the convex portion 41a are continuous. The corrugated irregularities are formed. The recess 41a is a groove that is long in the length direction of the cushion member 31a. However, the recess 41a may be a dot-shaped hole, as in the first embodiment. The through-passage 32a has a corrugated concavo-convex formed on the outer peripheral surface thereof in accordance with the concavo-convex shape of the cushion member 31a. The heat dissipation structure 25a having such a configuration also exhibits the same effects as the heat dissipation structure 25 described above. In addition, in this embodiment, the cushion member 31a is a member having a lower thermal conductivity than the thermal conductive sheet 30. Further, the number and position of the unevenness of the cushion member 31a are not particularly limited.

(Third Embodiment)
Next, a heat dissipation structure according to the third embodiment and a battery including the heat dissipation structure will be described. The same parts as those in the above-described respective embodiments are designated by the same reference numerals, and duplicate description will be omitted.

FIG. 4 (4B) shows a partially enlarged view of the cross-sectional view of the heat dissipation structure according to the third embodiment.

Unlike the heat dissipation structure 25 according to the first embodiment, the heat dissipation structure 25b according to the third embodiment has a rectangular recess 40b and a rectangular protrusion on the surface of the cushion member 31b opposite to the heat conductive sheet 30. Concavities and convexities in which the portion 41b is continuous are formed. In addition, the through passage 32b is formed with unevenness on the outer peripheral surface thereof according to the uneven shape of the cushion member 31b. The configuration other than the cushion member 31b and the through passage 32b is the same as that of the first embodiment, and thus the description thereof is omitted.

The cushion member 31b of the heat dissipation member 28b projects toward the heat conductive sheet 30 side and the rectangular recess 40b recessed toward the heat conductive sheet 30 on the surface opposite to the heat conductive sheet 30, that is, the surface on the side of the through passage 32b. The rectangular convex portion 41b has a concavo-convex pattern. The recess 40b is a groove that is long in the length direction of the cushion member 31b. However, the recess 40b may be a dot-shaped hole, as in the first embodiment. The through-passage 32b has an uneven shape in which a rectangular concave portion and a rectangular convex portion are continuously formed on the outer peripheral surface according to the uneven shape of the cushion member 31b. The heat dissipation structure 25b having such a configuration also exhibits the same effects as the heat dissipation structure 25 described above. In addition, in this embodiment, the cushion member 31b is a member having a lower thermal conductivity than the thermal conductive sheet 30. Further, the number and position of the unevenness of the cushion member 31b are not particularly limited.

(Fourth Embodiment)
Next, a heat dissipation structure according to the fourth embodiment and a battery including the heat dissipation structure will be described. The same parts as those in the above-described respective embodiments are designated by the same reference numerals, and duplicate description will be omitted.

FIG. 5 is a plan view (5A) of the heat dissipation structure according to the fourth embodiment, a sectional view (5B) taken along the line C-C in (5A), and an enlarged view (5C) of a region D in the sectional view. Shown respectively. FIG. 6 is a vertical cross-sectional view (6A) of the heat dissipation structure according to the second embodiment and a battery including the heat dissipation structure, and a heat dissipation structure before and after the heat dissipation structure is compressed by the battery cells in (6A). Sectional drawing (6B) of a form change is shown, respectively.

Unlike the battery 1 according to the first embodiment, the battery 1a according to the fourth embodiment includes a heat dissipation structure 25c in which a plurality of heat dissipation members 28 are connected by a connecting member 35a. Since the configuration other than the connecting member 35a is common to the first embodiment, the description thereof will be omitted.

Similar to the first embodiment, the connecting member 35a is a member such as a thread or a rubber made of a deformable material at least at a portion located between the plurality of heat dissipation members 28. In the present embodiment, the connecting member 35a is preferably made of a thread, and more preferably a thread that can withstand a temperature rise due to heat dissipation from the battery cells 20. The connecting member 35a is a member for sewing the plurality of heat dissipation members 28 using a sewing machine or the like. The sewing method of the connecting member 35a is not particularly limited, and any sewing method such as hand sewing, lock stitch, zigzag stitch, single chain stitch, double chain stitch, overlock stitch, flat stitch, safety stitch, and overlock may be used. Further, according to the display symbols defined by JIS L 0120, suitable sewing methods are “101”, “209”, “301”, “304”, “401”, “406”, “407”, “410”. , "501", "502", "503", "504", "505", "509", "512", "514", "602" and "605" It can be illustrated. Note that the connecting member 35a does not include the twisted portion 37 between the plurality of heat dissipation members 28, unlike the connecting member 35 according to the first embodiment.

The heat dissipation structure 25c has a plurality of heat dissipation members 28 manufactured by the same manufacturing method as in the first embodiment arranged in a direction orthogonal to the direction in which the heat conduction sheet 30 advances while being wound, and the connecting member 35a. It is manufactured by connecting with. More specifically, the heat dissipation structure 25c is connected by sewing a plurality of heat dissipation members 28 side by side with a thread using a sewing machine or the like. At this time, the heat dissipating members 28 are arranged so as to be spaced apart from each other so that the distance L2 between the plurality of heat dissipating members 28 is smaller than L1 (see FIG. 5C). Specifically, L2 is set to a distance (=0.114D) of 11.4% of the circle-converted diameter D of the heat dissipation member 28. Under this condition, the heat dissipation member 28 can be crushed in the vertical direction up to a thickness of about 80% of the circle equivalent diameter D. If the gap L2 is set to 0.114D or more, when the heat dissipation member 28 is compressed and deformed to a thickness of 80% or less of the circle-converted diameter D, the adjacent heat dissipation member 28 does not hinder the deformation. Note that the narrower the distance L2 between the plurality of heat radiating members 28, the more stably the plurality of heat radiating members 28 can be connected when sewing with a sewing machine or the like. The heat dissipation member 28 has a room to be crushed in the vertical and horizontal directions up to the position where the adjacent heat dissipation members 28 contact each other, so that the heat dissipation member 28 can follow the surface of the battery cell 20 and be in close contact therewith. The heat dissipation structure 25c can return to its original shape by the elastic force of the heat dissipation member 28 when the battery cells 20 are removed. Further, in the heat dissipation structure 25c, since the cushion member 31 includes the recess 40 on the surface opposite to the heat conductive sheet 30, the cushion member 31 generated when the heat dissipation structure 25 is crushed by being pressed by the battery cells 20. The stress can be reduced, and damage to the heat conductive sheet 30 can be suppressed. Further, in the heat dissipation structure 25c, since the plurality of heat dissipation members 28 are connected in a blind shape, it is possible to suppress a situation in which the heat dissipation members 28 are unevenly distributed due to, for example, vibration of an automobile, and the workability is improved. In particular, since the heat dissipation structure 25c connects the plurality of heat dissipation members 28 with the connecting member 35a using a sewing machine or the like, the workability becomes higher when the number of the heat dissipation members 28 configuring the heat dissipation structure 25c is large. ..

(Fifth Embodiment)
Next, a heat dissipation structure according to the fifth embodiment and a battery including the heat dissipation structure will be described. The same parts as those in the above-described respective embodiments are designated by the same reference numerals, and duplicate description will be omitted.

FIG. 7 is a vertical cross-sectional view of a heat dissipation structure according to the fifth embodiment and a battery including the heat dissipation structure. FIG. 8 shows a part (8A) of a manufacturing state of the heat dissipation structure of FIG. 7 and a plan view (8B) of the heat dissipation structure completed by the manufacturing method of (8A).

The battery 1b according to the fifth embodiment includes a heat dissipation structure 25d that is different from the heat dissipation structure 25 arranged in the battery 1 according to the first embodiment, and otherwise has the same structure as the battery 1. In the heat dissipation structure 25d used in this embodiment, a plurality of heat dissipation members 28c different from the heat dissipation member 28 according to the first embodiment are connected by a connecting member 35. Unlike the cylindrical cushion member 31 according to the first embodiment, the heat dissipation member 28c is a strip-shaped cushion member provided on the back side of the heat conductive sheet 30 and is spirally wound with the heat conductive sheet 30 in a spiral shape. Of the cushion member 31c.

An example of a method of manufacturing the heat dissipation structure 25d including the above-mentioned spiral cushion member 31c (hereinafter also referred to as "spiral cushion member 31c" or simply "cushion member 31c") is as follows.

First, the laminated body 50 including two layers of the heat conductive sheet 30 and the cushion member 31c having substantially the same width is manufactured. The cushion member 31c is provided with a plurality of recesses 40c recessed toward the heat conductive sheet 30 on the surface opposite to the heat conductive sheet 30. Next, heat conductive oil is applied to the surface of the heat conductive sheet 30. Then, the laminated body 50 coated with the heat conductive oil is wound in a spiral shape (may be referred to as a coil shape) so as to advance in one direction. Thus, the elongated heat dissipation member 28c in which the laminated body 50 is spirally wound is completed. The heat dissipation member 28c is provided with the recess 40c so that the cushion member 31c has a non-uniform thickness. The cushion member 31c is not particularly limited in the method of forming the recess 40c as long as the cushion member 31c has one or more recesses 40c recessed toward the heat transfer sheet 30 on the surface opposite to the heat transfer sheet 30. For example, the recess 40c may be formed by embossing or blasting. Further, the size, shape, and number of the recesses 40c are not particularly limited. The recess 40c is a dot-shaped hole, but may be a groove provided on the surface of the cushion member 31c and extending in a regular or irregular direction. Further, the heat conductive oil may be applied on the heat conductive sheet 30 before manufacturing the laminated body 50, or may be finally applied on the heat conductive sheet 30. In the laminated body 50, preferably, the cushion member 31c is not completely cured, and the heat conductive sheet 30 is laminated on the cushion member 31c, and then the cushion member 31c is completely cured by heating. Formed.

The heat dissipation structure 25d is manufactured by connecting a plurality of heat dissipation members 28c with a connecting member 35 in a state where they are arranged in a direction orthogonal to the direction in which the heat conduction sheet 30 advances while being wound. Since the method of connecting the plurality of heat dissipation members 28c with the connecting member 35 is the same as that of the first embodiment, detailed description thereof will be omitted.

The heat dissipation member 28c has a through passage 33 that penetrates in the length direction thereof, but unlike the heat dissipation member 28 according to the first embodiment, the heat dissipation member 28c also penetrates in the outer surface direction of the heat dissipation member 28c. Since the heat dissipation member 28c has a spiral shape, it is easier to expand and contract in the length direction of the heat dissipation member 28c (the direction of the white arrow in FIG. 8B) than the heat dissipation member 28 described above.

The heat dissipation structure 25d can be arranged not only between the battery cells 20 and the bottom portion 12 of the housing 11, but also in the clearance between the battery cells 20 and the inner surface of the housing 11 and/or the clearance between the battery cells 20. Is.

(Operation and effect of each embodiment)
As described above, the heat dissipation structures 25, 25a, 25b, 25c, 25d (when the heat dissipation structures are collectively referred to as “heat dissipation structure 25 etc.”), the heat dissipation from the battery cells 20 is enhanced. A heat dissipating structure in which a plurality of heat dissipating members 28, 28a, 28b, 28c (when the heat dissipating members are collectively referred to as "heat dissipating member 28 or the like") are connected, the heat dissipating member 28 or the like is a battery cell. The heat conductive sheet 30 having a shape that advances in a spiral shape for transmitting heat from the heat conductive sheet 20, and an annular back surface of the heat conductive sheet 30 are provided so as to match the surface shape of the battery cell 20 as compared with the heat conductive sheet 30. And easily deformable cushion members 31, 31a, 31b, 31c (when the cushion members are collectively referred to as "cushion member 31 and the like"), the heat conduction sheet 30 penetrates in a direction in which the heat conduction sheet 30 advances while being wound. And the cushion members 31 and the like are made nonuniform in thickness, and the plurality of heat radiating members 28 and the like are orthogonal to the direction in which the heat conducting sheet 30 advances while being wound. They are connected by the connecting members 35 and 35a in a state in which they are aligned in the direction.

By configuring the heat dissipation structure 25 and the like in this manner, it is possible to adapt to various forms of the battery cell 20, has excellent heat dissipation efficiency, is highly elastically deformable, and suppresses damage due to pressing from the battery cell 20. It becomes a possible structure. Further, the heat dissipation structure 25 and the like become lighter due to the through passages 32, 32a, 32b, and 33.

Further, the cushion member 31 or the like constituting the heat dissipation structure 25 or the like has one or more recesses 40, 40a, 40b, 40c (recesses) recessed toward the heat conductive sheet 30 on the surface opposite to the heat conductive sheet 30. Are collectively referred to as "recess 40 and the like"). Therefore, the heat dissipation structure 25 and the like can reduce the stress of the cushion member 31 and the like that occurs when the heat dissipation structure 25 is pressed and crushed by the battery cells 20, and the damage of the heat conductive sheet 30 can be suppressed.

Further, since the cushion member 31 and the like that configure the heat dissipation structure 25 and the like have continuous irregularities on the surface opposite to the heat conductive sheet 30 at predetermined intervals, they are generated when they are crushed by being pressed by the battery cell 20. The stress of the cushion member 31 and the like can be further reduced, and damage to the heat conductive sheet 30 can be suppressed.

Further, the cushion members 31, 31a, 31b forming the heat dissipation structures 25, 25a, 25b, 25c are tubular cushion members having through passages 32, 32a, 32b in the length direction thereof, and the heat conduction sheet 30. Wraps the outer surfaces of the tubular cushion members 31, 31a, 31b in a spiral shape. The batteries 1 and 1 a are provided in the housing 11 by bringing the heat dissipation structure 25 and the like into contact with the battery cells 20. The heat conduction sheet 30 partially covers the outer surfaces of the tubular cushion members 31, 31a, 31b, and is spirally wound in the longitudinal direction of the tubular cushion members 31, 31a, 31b. In the batteries 1 and 1 a, the heat dissipation structures 25 and 25 a are arranged at least between the battery 20 and the cooling member 15. For this reason, the heat dissipation structures 25 and 25a are less likely to be constrained by the heat conductive sheet 30, and can be deformed by following irregularities on the surface of the battery cell 20.

Further, in the heat dissipation structure 25d, the cushion member 31c is a spiral cushion member that is spirally wound along the annular back surface of the heat conductive sheet 30. In the battery 1b, the heat dissipation structure 25d is arranged at least between the battery 20 and the cooling member 15. The heat dissipation structure 25d may be arranged between the inner surface of the housing 11 and the battery cells 20 and/or between the battery cells 20. Since the entire heat dissipation structure 25d has a spiral shape, it is easier to adapt to various sizes of the battery cell 20. More specifically, it is as follows. Even when the heat conductive sheet 30 having high rigidity is provided, the heat conductive sheet 30 can be deformed with a low load so as to follow and adhere to the surface of the battery cell 20. Further, even if the deformation amount is partially different, the adhesion followability is improved. Further, since the cushion member 31c is also cut in a spiral shape, it is possible to cause deformation as if the spirals for each rotation were substantially independent. Therefore, the heat dissipation structure 25d can increase the degree of freedom of local deformation. In addition, since the heat dissipation structure 25d includes not only the through passage 33 but also a spiral through groove that extends from the through passage 33 to the side surface, the heat dissipation structure 25d becomes lighter in weight.

The connecting member 35 is made of yarn, and includes a twisted portion 37 in which twist is added between the plurality of heat dissipation members 28 and the like. The plurality of heat dissipating members 28 and the like are connected by threads in a direction orthogonal to the direction in which the heat conducting sheet 30 advances while being wound. Therefore, in the heat dissipation structure 25 and the like, since the plurality of heat dissipation members 28 and the like are connected in a blind shape, it is possible to suppress the situation where the heat dissipation members 28 and the like are unevenly distributed due to, for example, vibration of an automobile, and the workability is improved.

In addition, the plurality of heat dissipation members 28 and the like are arranged at a distance of 0.114 times or more the circle-converted diameter D of the heat dissipation members 28 and the like. The connecting member 35 is preferably contractable or deformable between the plurality of heat dissipation members 28 and the like. Therefore, even when the heat dissipation member 28 or the like is compressed to 80% of the original height in the battery cell 20, the adjacent heat dissipation member 28 or the like is in a flat state without overlapping, so that the battery cell 20 It is possible to further improve the followability and adhesion to the surface of. By sufficiently compressing and deforming the heat dissipating members 28 and the like, when the weight from the battery cells 20 is added, the battery cells 20 and the heat dissipating members 28 and the like are sufficiently brought into close contact with each other, whereby the battery cells 20 and the heat dissipating are dissipated. The thermal conductivity with the member 28 and the like can be further enhanced.

In addition, the surface of the heat conductive sheet 30 has a heat conductive oil for increasing the heat conductivity from the battery cells 20 contacting the surface to the surface. Microscopically, the heat conductive sheet 30 has a gap (hole or recess). Air is usually present in the gap, which may adversely affect the thermal conductivity. The heat conductive oil fills the gap and exists instead of air, and has a function of improving the heat conductivity of the heat conductive sheet 30.

The heat conductive oil includes silicone oil and a heat conductive filler having higher heat conductivity than silicone oil and made of one or more of metal, ceramics or carbon. Since silicone oil is an oil having excellent heat resistance, cold resistance, viscosity stability, and thermal conductivity, it is applied on the surface of the thermal conductive sheet 30 and is interposed between the battery cell 20 and the thermal conductive sheet 30. It is particularly suitable as a heat conductive oil. In addition, since the heat conductive oil contains the heat conductive filler, the heat conductivity of the heat conductive sheet 30 can be enhanced.

Each of the batteries 1, 1a, 1b is a battery including one or more battery cells 20 as a heat source in a housing 11 having a structure for flowing the cooling member 15, and includes the above-described heat dissipation structure 25 and the like. .. The heat dissipation structure 25 and the like are connected with a plurality of heat dissipation members 28 and the like that enhance heat dissipation from the battery cells 20. The heat dissipation structures 25 and the like are wound around the heat dissipation members 28 and the like in a spiral shape for transferring heat from the battery cells 20 to proceed. Of the heat conduction sheet 30, and the cushion member 31 and the like provided on the annular back surface of the heat conduction sheet 30 and more easily deformed according to the surface shape of the battery cell 20 than the heat conduction sheet 30, and the heat conduction sheet 30. The through passages 32, 32a, 32b, 33 are formed so as to penetrate in the traveling direction while being wound. The cushion member 31 and the like are made to have an uneven thickness, and the plurality of heat radiating members 28 and the like are arranged by the connecting members 35 and 35a in a state of being aligned in a direction orthogonal to the direction in which the heat conducting sheet 30 advances while being wound. Be connected. By configuring the batteries 1, 1a, 1b in this way, it is possible to adapt to various forms of the battery cell 20, the heat dissipation efficiency is excellent, the elastic deformation is rich, and the damage caused by the pressure from the battery cell 20 is prevented. The battery includes the heat dissipation structure 25 that can be suppressed. Further, the batteries 1, 1a, 1b are lighter due to the through passages 32, 32a, 32b, 33.

(Other embodiments)
Although the preferred embodiments of the present invention have been described above, the present invention is not limited to these and can be modified in various ways.

FIG. 9 shows a cross-sectional view of a battery cell placed laterally on the heat dissipation structure so that the side surfaces of the battery cell are in contact with each other, a partially enlarged view of the battery cell, and a partial cross-sectional view of the battery cell when expanded during charging and discharging. Shown respectively.

In the first embodiment, the situation in which the battery cell 20 is vertically arranged and the heat dissipation structure 25 is in contact with the lower end of the battery cell 20 has been described, but the arrangement form of the battery cell 20 is not limited to this. As shown in FIG. 9, the battery cell 20 may be arranged so that the side surface of the battery cell 20 is in contact with each heat dissipation member 28 of the heat dissipation structure 25. The temperature of the battery cell 20 rises during charging and discharging. If the container itself of the battery cell 20 is formed of a highly flexible material, there is a possibility that the side surface of the battery cell 20 particularly swells. Even in such a case, as shown in FIG. 9, since each heat dissipation member 28 included in the heat dissipation structure 25 can be deformed according to the shape of the outer surface of the battery cell 20, the heat dissipation is maintained high even during charging and discharging. it can. The arrangement form of the battery cells 20 is not limited to the first embodiment, and similarly in each of the above-described embodiments, the side surface of the battery cell 20 is brought into contact with each heat dissipation member 28 such as the heat dissipation structure 25. Alternatively, the battery cell 20 may be arranged.

Further, the heat source includes not only the battery cells 20 but also all objects that generate heat, such as the circuit board and the main body of the electronic device. For example, the heat source may be an electronic component such as a capacitor and an IC chip. Similarly, the cooling member 15 may be not only water for cooling but also an organic solvent, liquid nitrogen, or a gas for cooling. Further, the heat dissipation structure 25 and the like may be arranged in structures other than the battery 1 and the like, for example, electronic devices, home appliances, power generators, and the like.

Further, the recess 40 or the like of the cushion member 31 or the like is not particularly limited in shape as long as it is recessed toward the heat conductive sheet 30 on the surface opposite to the heat conductive sheet 30, and for example, a trapezoidal shape, a polygonal shape, or the like. You can have it. Further, the size of the recess 40 and the like of the cushion member 31 and the like is not particularly limited.

Further, if the cushion member 31 and the like have at least one recess 40 or the like recessed toward the heat conductive sheet 30 on the surface opposite to the heat conductive sheet 30, there is no restriction on the arrangement of the recess 40 or the like, For example, the plurality of recesses 40 and the like may be arranged unevenly.

Further, the cushion member 31 and the like may not be provided with the recess 40 and the like on the surface opposite to the heat conductive sheet 30 as long as the cushion member 31 and the like are formed so as to have a nonuniform thickness.

Further, the spiral cushion member 31c of the heat dissipation member 28d is not limited to the same width as the heat conduction sheet 30, and may be larger or smaller than the width of the heat conduction sheet 30.

Further, the plurality of constituent elements of each of the above-described embodiments can be freely combined, except when they cannot be combined with each other. For example, the heat dissipation member 28a according to the second embodiment may be arranged instead of the heat dissipation member 28 according to the fourth embodiment.

INDUSTRIAL APPLICABILITY The heat dissipation structure according to the present invention can be used in various electronic devices such as automobiles, industrial robots, power generators, PCs, household appliances, as well as automobile batteries. Further, the battery according to the present invention can be used not only as a battery for an automobile but also as a household chargeable/dischargeable battery and a battery for electronic equipment such as a PC.

1, 1a, 1b... Battery, 11... Housing, 15... Cooling member, 20... Battery cell (an example of heat source), 25, 25a, 25b, 25c, 25d... Heat dissipation structure , 28, 28a, 28b, 28c... Heat dissipation member, 30... Heat conductive sheet, 31, 31a, 31b, 31c... Cushion member, 32, 32a, 32b, 33... Through passage, 35, 35a... Connection member, 37... Twisted portion, 40, 40a, 40b, 40c... Recessed portion.

Claims (10)

A heat dissipation structure in which a plurality of heat dissipation members that enhance heat dissipation from a heat source are connected,
The heat dissipation member is
A heat conductive sheet having a shape that advances while being wound in a spiral for transmitting heat from the heat source,
A cushion member provided on the annular back surface of the heat conductive sheet, which is easily deformable in accordance with the surface shape of the heat source compared to the heat conductive sheet,
A through path that penetrates in the direction in which the heat conductive sheet advances while being wound,
Equipped with
The cushion member has a non-uniform thickness,
A heat dissipation structure in which the plurality of heat dissipation members are connected by a connection member in a state of being aligned in a direction orthogonal to a direction in which the heat conduction sheet advances while being wound. The heat dissipation structure according to claim 1, wherein the cushion member is provided with one or two or more recesses that are recessed toward the heat conductive sheet, on a surface opposite to the heat conductive sheet. The heat dissipation structure according to claim 2, wherein the cushion member has concavities and convexities that are continuous at a predetermined interval on a surface opposite to the heat conductive sheet. The cushion member is a tubular cushion member having the through passage in its length direction,
The heat dissipation structure according to any one of claims 1 to 3, wherein the heat conduction sheet spirally winds an outer surface of the tubular cushion member. The heat dissipation structure according to claim 1, wherein the cushion member is a spiral cushion member that is spirally wound along the annular back surface of the heat conductive sheet. The connecting member is formed of a yarn, and includes a twisted portion to which twist is added between the plurality of heat dissipation members,
The heat dissipation structure according to any one of claims 1 to 5, wherein the plurality of heat dissipation members are connected by the thread in a direction orthogonal to a direction in which the heat conduction sheet advances while being wound. The heat dissipation structure according to any one of claims 1 to 6, wherein the plurality of heat dissipation members are arranged at a distance of 0.114 times or more of a circle equivalent diameter of the heat dissipation member. The heat dissipation structure according to claim 1, further comprising a heat conductive oil for increasing heat conductivity from a heat source in contact with the surface to the surface, on the surface of the heat conductive sheet. The heat dissipation structure according to claim 8, wherein the heat conductive oil includes a silicone oil and a heat conductive filler having higher heat conductivity than the silicone oil and made of one or more of metal, ceramics or carbon. A battery having one or more battery cells as a heat source in a housing having a structure for flowing a cooling member, wherein the battery cell is between the battery cell and the housing. A battery comprising the heat dissipation structure according to item.