CROSS REFERENCE

The present application claims the benefit of priorities of Japanese Patent Application No. 2019-020327 filed on Feb. 7, 2019 the entire contents of which are incorporated herein by reference. The entire contents of patents, patent applications, and literatures cited in the present application are also incorporated herein by reference.

TECHNICAL FIELD

The present invention relates to a heat dissipating structure and a battery provided with the same.

RELATED ART

A control system of automobiles, aircrafts, ships or electronic devices for home use or business use has become further complicated and highly accurate, and correspondingly the integration of small electronic components on a circuit board has been increasingly densified. As a result, it is strongly requested to solve malfunction or shortening of service life of the electronic components owing to heat generated in the periphery of the circuit board.

Conventionally, rapid heat dissipation from the circuit board has been implemented by using the material excellent in heat dissipation, mounting the heat sink, and driving a cooling fan either in an individual or complex manner. Above all, the method of forming the circuit board itself using the material excellent in heat dissipation, for example, diamond, aluminum nitride (AlN), cubic boron nitride (cBN) or the like extremely increases the cost of the circuit board. Additionally, placement of the cooling fan causes problems of malfunction of a fan as the rotator, need of maintenance for preventing the malfunction, and difficulty in securing a mount space. Meanwhile, a heat dissipating fin is a simple member capable of increasing a surface area by forming many columnar or flat plate-like projections made of high heat conduction metal (for example, aluminum) to further enhance heat dissipation. The heat dissipating fin has been generally used as the heat dissipating component (see Japanese Patent Laid-Open No. 2008-243999).

Recently, for the purpose of reducing a load to global environment, conversion of a conventional gasoline-powered vehicle or a diesel vehicle into an electric automobile has become a global upward trend. Particularly, in China as well as European countries such as France, Netherlands, and Germany, electric automobiles have been widely adopted. To encourage widespread adoption of electric automobiles, constructing charging stands is required in addition to development of high-performance batteries. Particularly, technological development for enhancing a charging-discharging function of a lithium automobile battery is an important issue. It is well known that automobile batteries cannot sufficiently exert charging-discharging functions under a high temperature of 60° C. or higher. Therefore, as with the aforementioned circuit board, heat dissipating enhancement is regarded as an important issue for the battery.

In order to implement the rapid heat dissipation from the battery, the structure to be described below has been employed. The structure is formed by disposing a water-cooling pipe in a housing formed of metal excellent in heat conductivity such as aluminum. Many battery cells are disposed in the housing, and a rubber sheet with adhesiveness is interposed between the battery cells and a bottom surface of the housing. The above-structured battery allows the battery cells to conduct heat to the housing via the rubber sheet, and to effectively remove heat through water cooling.

The heat conductivity of the rubber sheet used for the generally employed battery is lower than that of aluminum or graphite. Therefore it is difficult to effectively transfer heat from the battery cells to the housing. The use of a spacer of graphite or the like to be interposed in place of the rubber sheet may be considered.

However, as the battery cells are not flat because of stepped lower surfaces, gaps are formed between the battery cells and the spacer, resulting in deteriorated heat conduction efficiency. As described in the example, the battery cells can take various forms (including uneven or non-smooth surface state such as the stepped portion), and therefore the demand for adaptability to the various forms of the battery cells, and achievement of high heat conduction efficiency has been increasing. Preferably, in order to achieve high heat conduction efficiency, the heat dissipation from each battery cell is made uniform to allow each of the battery cells to have uniform temperature. Furthermore, the use of an elastically deformable material lighter in weight for the container of the battery cell has been demanded. A heat dissipating structure has been demanded to allow weight dissipation of the battery cell, and restoration of the shape nearly to the original state after removing the battery cells. This applies not only to the battery cell but also to other heat sources such as the circuit board, the electronic component, and the electronic device body.

The present invention provides a heat dissipating structure adaptable to various forms of heat source, light in weight, elastically deformable, excellent in heat dissipating efficiency, and capable of enhancing uniformity in heat dissipation from the respective heat sources, and a battery provided with the heat dissipating structure.

SUMMARY

(1) A heat dissipating structure has a plurality of heat dissipating members connected for enhancing heat dissipation from a heat source and a fixation member. Each of the heat dissipating members includes a heat conduction sheet in a spirally winding shape for conducting heat from the heat source, a cushion member that is provided on an annular back surface of the heat conduction sheet, and is deformable following a surface shape of the heat source more easily than the heat conduction sheet, and a through passage penetrating in a winding direction of the heat conduction sheet. The fixation member fixes the heat dissipating members orthogonally arranged to a longitudinal direction of the heat dissipating member. The fixation member fixes at least one end of each of the heat dissipating members in the longitudinal direction.

(2) In the heat dissipating structure, preferably, the fixation member fixes both ends of each of the heat dissipating members in the longitudinal direction.

(3) In the heat dissipating structure, preferably, the fixation member is formed to surround the heat dissipating members orthogonally arranged to the longitudinal direction of the heat dissipating member.

(4) In the heat dissipating structure, preferably, the fixation member is formed to have a thickness smaller than a thickness of the heat dissipating member deformed under pressure force applied from the heat source.

(5) In the heat dissipating structure, preferably, the cushion member is cylindrically shaped, and includes the through passage extending in the longitudinal direction. The heat conduction sheet is spirally wound around an outer surface of the cylindrically shaped cushion member.

(6) In the heat dissipating structure, preferably, the cushion member is spirally shaped, and spirally winding along the annular back surface of the heat conduction sheet.

(7) Preferably, the heat dissipating structure includes a connection member for connecting the heat dissipating members orthogonally arranged to the longitudinal direction. The connection member is formed of a thread.

(8) In the heat dissipating structure, preferably, the connection member includes a twisted portion interposed between the heat dissipating members.

(9) In the heat dissipating structure, preferably, a heat conduction oil is applied to a surface of the heat conduction sheet for enhancing heat conductivity to the surface from the heat source in contact with the surface.

(10) In the heat dissipating structure, preferably, the heat conduction oil contains a silicone oil and a heat conduction filler that exhibits higher heat conductivity than the silicone oil. The heat conduction filler is formed of at least one of metal, ceramics, and carbon.

(11) A battery includes one or more battery cells each as a heat source in a housing that allows flow of a cooling agent. The heat dissipating structure of any one of (1) to (10) is disposed between the battery cell and the housing.

ADVANTAGEOUS EFFECT OF INVENTION

The present invention provides a heat dissipating structure adaptable to various forms of heat source, light in weight, elastically deformable, excellent in heat dissipating efficiency, and capable of enhancing uniformity in heat dissipation from the respective heat sources, and a battery provided with the heat dissipating structure.

