Patent Description:
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 <CIT>).

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 <NUM> 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.

<CIT>, which was published after the priority date of the present disclosure, relates to a heat dissipating structure adaptable to various forms of a heat source, and a battery provided with the heat dissipating structure. The heat dissipating structure enables heat dissipation from a heat source and comprises a heat conduction sheet in a spirally wound shape for conducting heat from the heat source, a cushion member provided on an annular back surface of the heat conduction sheet, and easily deformed corresponding to a surface shape of the heat source compared to the heat conduction sheet, and a through passage penetrating in a direction in which the heat conduction sheet in the wound shape runs, and a battery provided with the same.

<CIT> relates to a device for the temperature control of battery cells in a battery includes a contact surface for thermally contacting the battery cells with the device. The contact surface is configured such that the battery cells to be temperature-controlled are arranged on the contact surface. The device has elements below the contact surface that are elastically restoring such that, when a compressive load acting orthogonally to the contact surface is applied, the contact surface is lowered in the region of the applied compressive load. A restoring force acts against the compressive load.

<CIT> relates to a cooling plate, a battery module including the same, and a method for manufacturing the same. The cooling plate is interposed between a cooling unit that is in thermal contact with battery cells on at least one surface of a stack of battery cells and the battery cells, and includes a metal plating layer on the surface of a substrate made of a synthetic resin.

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.

The presently claimed invention relates to a heat dissipating structure according to claim <NUM>.

Embodiments of the present invention are described referring to the drawings. Each embodiment described herein does not limit the invention according to the scope of the claims, and all elements described in each embodiment, and all combinations thereof are not necessarily essential for implementing the present invention.

<FIG> is a plan view of a heat dissipating structure according to a first embodiment. <FIG> is a longitudinal sectional view taken along line A-A of <FIG> is an enlarged view of a region B as shown in <FIG>. <FIG> is a side view of the heat dissipating structure of <FIG> viewed from an arrow C direction. <FIG> is a side view of the heat dissipating structure of <FIG> viewed from an arrow D direction. <FIG> is an enlarged view of a region E of <FIG>. <FIG> is a longitudinal sectional view of the heat dissipating structure according to the first embodiment, and a battery provided with the heat dissipating structure. <FIG> is a sectional view illustrating change in the formation of the heat dissipating structure before and after it is compressed by battery cells as shown in <FIG>.

As illustrated in <FIG>, a battery <NUM> is structured to have a plurality of battery cells <NUM> in a housing <NUM> in contact with cooling agent <NUM>. Preferably, a heat dissipating structure <NUM> is provided between the battery cells <NUM> as heat sources at proximal ends (lower ends) closer to the cooling agent <NUM>, and a part (bottom <NUM>) of the housing <NUM> at a side closer to the cooling agent <NUM>. The word, "heat dissipating structure" may be called as "thermal conductor", "thermal conductive body" or "thermal conductive structure". As illustrated, the heat dissipating structure <NUM> accommodates <NUM> battery cells <NUM>. However, the number of the battery cells <NUM> to be placed on the heat dissipating structure <NUM> is not limited to <NUM>. The number of heat dissipating members <NUM> constituting the heat dissipating structure <NUM> disposed in the battery <NUM> is not specifically limited.

The heat dissipating structure <NUM> is formed with the heat dissipating members <NUM> connected for enhancing heat dissipation from the battery cells <NUM>. The heat dissipating member <NUM> includes a spirally winding heat conduction sheet <NUM> for conducting heat from the battery cell <NUM>, a cushion member <NUM> that is provided on an annular back surface of the heat conduction sheet <NUM>, and more deformable following the surface shape of the battery cell <NUM> than the heat conduction sheet <NUM>, and a through passage <NUM> penetrating in the spirally winding direction of the heat conduction sheet <NUM>. The heat dissipating structure <NUM> includes a fixation member <NUM> capable of fixing the heat dissipating members <NUM> (in X direction of <FIG>) orthogonally arranged to the longitudinal direction, specifically, at least one longitudinal ends of the heat dissipating members <NUM> (in Y direction of <FIG>). Preferably, the fixation member <NUM> fixes both longitudinal ends of the heat dissipating members <NUM>. The heat conduction sheet <NUM> is preferably formed of a material with superior heat conductivity to that of the cushion member <NUM>. The cushion member <NUM> is preferably formed in a cylindrical shape, having a through passage <NUM> in the longitudinal direction. The heat conduction sheet <NUM> is spirally wound around an outer surface of the cylindrical cushion member. Preferably, the heat dissipating structure <NUM> has a connection member <NUM> for connecting the heat dissipating members <NUM> (in X direction of <FIG>) orthogonally arranged to the longitudinal direction. Preferably, in the heat dissipating structure <NUM>, heat conduction oil is applied to the surface and/or inside of the heat conduction sheet <NUM> for enhancing heat conductivity to the surface from the battery cells <NUM> in contact therewith. Each of the heat dissipating members <NUM> constituting the heat dissipating structure <NUM> has a substantially cylindrical shape when the battery cells <NUM> are not mounted. Once the battery cells <NUM> are mounted, the heat dissipating members <NUM> will be compressed and flattened under the heavy load.

The heat conduction sheet <NUM> has a belt-like shape while spirally winding in the longitudinal direction of the substantially cylindrical shape around the outer surface of the heat dissipating member <NUM>. The heat conduction sheet <NUM> contains at least one of metal, carbon, and ceramics, and has a function of conducting heat from the battery cells <NUM> to the cooling agent <NUM>. The term "cross section" or "longitudinal cross section" to be used herein refers to a cross section in a vertically cutting direction from an upper opening surface of an inside <NUM> of the housing <NUM> of the battery <NUM> to the bottom <NUM>.

Schematic structures of the battery <NUM> and components of the heat dissipating structure <NUM> are described in more detail.

In this embodiment, the battery <NUM> is, for example, employed for an electric automobile, and includes many battery cells <NUM> (simply referred to as cells). The battery <NUM> includes a bottomed housing <NUM> having an opening on one side. The housing <NUM> is preferably formed of aluminum or aluminum base alloy. The cells <NUM> are disposed in the inside <NUM> of the housing <NUM>. Electrodes (not illustrated) project from the upper sides of the cells <NUM>, respectively. The cells <NUM> preferably in the housing <NUM> are in tight contact with each other (not illustrated) by application of force in the compressing direction from both sides by utilizing screws or the like. The bottom <NUM> of the housing <NUM> is provided with one or more water-cooling pipes <NUM> to allow flow of cooling water as the cooling agent <NUM>. The cooling agent may be referred to as a cooling medium or a cooling member. The cells <NUM> are disposed inside the housing <NUM> to interpose the heat dissipating structure <NUM> with the bottom <NUM>. In the above-structured battery <NUM>, heat of the cells <NUM> is conducted to the housing <NUM> through the heat dissipating structure <NUM> and effectively removed by water cooling. The cooling agent <NUM> is not limited to the cooling water, but may be interpreted to include an organic solvent such as liquid nitrogen and ethanol. The cooling agent <NUM> is not limited to liquid when used for cooling, but may be in gaseous or solid form.

The heat conduction sheet <NUM> preferably contains carbon, and more preferably contains carbon filler and resin. The resin may be replaced with a synthetic fiber. In this case, preferably, aramid fiber is usable. The "carbon" described herein may be widely interpreted to contain an arbitrary structure composed of carbon (C) such as graphite, carbon black with lower crystallinity than graphite, expanded graphite, diamond, diamond-like carbon having a similar structure to diamond. In this embodiment, the heat conduction sheet <NUM> may be a thin sheet obtained by curing a material having graphite fiber or carbon particles compounded and dispersed in resin. The heat conduction sheet <NUM> may be the carbon fiber formed through meshed weaving, mixed spinning, or mixed knitting. Various types of fillers such as graphite fiber, carbon particles, and carbon fiber may be considered to fall under the concept of the carbon filler.

The resin contained in the heat conduction sheet <NUM> may or may not exceed <NUM> mass% to the total mass of the heat conduction sheet <NUM>. That is, the resin may or may not be used as a main material for forming the heat conduction sheet <NUM> so long as the resultant heat conduction is not seriously affected. The thermoplastic resin may be suitably used as the resin, for example. It is preferable to use the resin with high melting point at which it may be kept unmelted in heat conduction from the cell <NUM> as the heat source, for example, polyphenylene sulfide (PPS), polyetheretherketone (PEEK), polyamide imide (PAI), and aromatic polyamide (aramid fiber). Before formation of the heat conduction sheet <NUM>, the resin is dispersed in gaps in the carbon filler in the form of particle or fiber. The heat conduction sheet <NUM> may be formed to have AIN or diamond dispersed as the filler for enhancing heat conduction besides the carbon filler, resin and the like. In place of the resin, elastomer more flexible than the resin may be used. The heat conduction sheet <NUM> may be formed as the sheet that contains metal and/or ceramics in place of or together with carbon. It is possible to selectively use metal with relatively high heat conductivity such as aluminum, copper, and an alloy containing at least one of those metals. It is possible to selectively use ceramics with relatively high heat conductivity such as AIN, cBN, and hBN.

The heat conduction sheet <NUM> may or may not be excellent in electrical conductivity. Preferably, the heat conductivity of the heat conduction sheet <NUM> is equal to or higher than <NUM> W/mK. In the embodiment, the heat conduction sheet <NUM> is preferably the belt-shaped plate formed of the material excellent in heat conductivity and electrical conductivity, for example, graphite, aluminum, aluminum alloy, copper, or stainless steel. Preferably, the heat conduction sheet <NUM> exhibits sufficient curving property (or bending property). Although the thickness of the sheet is not limited to the specific value, it is preferable to use a sheet with a thickness ranging from <NUM> to <NUM>, and more preferably, ranging from <NUM> to <NUM>. As the thickness increases, the heat conductivity of the heat conduction sheet <NUM> is lowered. It is preferable to determine the thickness by considering the balance among properties of the sheet such as strength, flexibility, and heat conductivity.

The cushion member <NUM> has essential functions of deformability and restorability. The restorability is determined by elastic deformation capability. The deformability is a necessary property for following the shape of the cell <NUM>. Particularly, the cell <NUM> in an easily deformable package that houses semisolid product such as lithium ion battery, a content having a liquid property and the like is likely to have its design dimension indeterminable, or its dimensional accuracy hardly improved. Therefore, it is important to secure the restorability to retain the deformability and the follow-up property of the cushion member <NUM>.

In this embodiment, the cushion member <NUM> is cylindrical, and includes the through passage <NUM>. Although the lower ends of the cells <NUM> are not flat, the cushion member <NUM> improves the contact between the heat conduction sheet <NUM> and the lower ends. The through passage <NUM> makes the cushion member <NUM> easily deformable, contributes to weight reduction in the heat dissipating structure <NUM>, and has a function of enhancing the contact between the heat conduction sheet <NUM> and the lower ends of the cells <NUM>. The cushion member <NUM> has a function as a protective member that prevents the heat conduction sheet <NUM> from being damaged due to the load applied thereto, in addition to a function of imparting a cushioning function between the cells <NUM> and the bottom <NUM>. In this embodiment, the cushion member <NUM> exhibits the heat conductivity lower than that of the heat conduction sheet <NUM>. In this embodiment, the through passage <NUM> has a circular cross section. However, the cross section of the through passage <NUM> is not limited to the circular shape, but may be polygonal, elliptical, semi-circular, and substantially polygonal with rounded vertex, for example. The cross section of the through passage <NUM> may be constituted by a plurality of through passages, for example, two semicircular cross sections either upper and lower sections, or left and right sections by dividing the circular cross section into two parts.

The cushion member <NUM> is preferably formed to contain thermosetting elastomer such as silicone rubber, urethane rubber, isoprene rubber, ethylene-propylene rubber, natural rubber, ethylene-propylene-diene rubber, nitrile rubber (NBR), styrene-butadiene rubber (SBR), and the like; urethane-based, ester-based, styrene-based, olefin-based, butadiene-based, or fluorine-based thermoplastic elastomer; or composite thereof. Preferably, the cushion member <NUM> is formed of a material with high heat resistance that allows retention of formation of the heat conduction sheet <NUM> without being molten or decomposed by the conducted heat. In this embodiment, more preferably, the cushion member <NUM> is formed of a material obtained by impregnating silicone into urethane-based elastomer, or silicone rubber. The cushion member <NUM> may be formed by dispersing the filler represented by, for example, particles of AlN, cBN, hBN, or diamond into rubber to enhance heat conductivity as high as possible. The cushion member <NUM> may or may not be formed as the material containing bubbles. The "cushion member" represents an elastically deformable member with high flexibility, and capable of being in tight contact with a surface of the heat source, and can be replaced with a term "rubber elastic structure" in the context herein. Furthermore, as a modification of the cushion member <NUM>, metal may be used in place of the rubber elastic structure. For example, the cushion member can be constituted by spring steel. Furthermore, as the cushion member <NUM>, a coil spring can be disposed. Additionally, spirally wound metal may be used as the spring steel, and disposed on the annular back surface of the heat conduction sheet <NUM> as the cushion member. The cushion member <NUM> can be constituted by a sponge made of resin and rubber, or a solid material (non-porous structure unlike the sponge).

The connection member <NUM> is formed of a material, for example, thread and rubber, which is partially deformable at least between the heat dissipating members <NUM>. In this embodiment, the connection member <NUM> is preferably formed of the thread. More preferably, the thread is resistant to temperature rise owing to heat dissipation from the cell <NUM>. Specifically, the connection member <NUM> is preferably formed of the thread that is resistant to high temperature of approximately <NUM>, and composed of a twisted yarn such fibers as natural fibers, synthetic fibers, carbon fibers, and metal fibers. Preferably, the connection member <NUM> includes twisted portions <NUM> each between the heat dissipating members <NUM> (see <FIG>). In the heat dissipating structure <NUM>, although the heat dissipating member <NUM> is flattened under the pressure force applied by the cell <NUM>, the connection member <NUM> flexibly deflects while following the deforming heat dissipating member <NUM>. This allows the heat dissipating structure <NUM> to follow and come into tight contact with the surface of the cell <NUM>. The heat dissipating structure <NUM> including the twisted portions <NUM> each interposed between the heat dissipating members <NUM> further enhances the follow-up property and adhesiveness with the surface of the cell <NUM>. However, the connection member <NUM> does not necessarily include the twisted portion <NUM>.

The fixation member <NUM> is capable of fixing the heat dissipating members <NUM> which are orthogonally arranged (in direction X of <FIG>) to the longitudinal direction of the heat dissipating member <NUM>. The fixation member <NUM> fixes at least one longitudinal ends of the respective heat dissipating members <NUM> (in direction Y of <FIG>). Preferably, the fixation member <NUM> surrounds orthogonally arranged heat dissipating members <NUM> to the longitudinal direction by fixing both longitudinal ends of each of the heat dissipating members <NUM>. In other words, the fixation member <NUM> includes a frame <NUM> that surrounds the heat dissipating members <NUM> both in the longitudinal direction and the direction (width direction) in which the heat dissipating members <NUM> are arranged. Two opposite sides (two sides in the longitudinal direction of the heat dissipating member <NUM>) of the frame <NUM> serve to fix the respective heat dissipating members <NUM>. Preferably, both ends of each of the heat dissipating member <NUM> are placed on the two opposite sides of the frame <NUM>, respectively, and sewn with a thread <NUM> for fixation. An opening <NUM> surrounded by the frame <NUM> is a region in which the heat dissipating members <NUM> may be compressed by the cells <NUM> toward the bottom <NUM>. Preferably, the opening <NUM> has a size sufficiently large to allow insertion of the cells <NUM>. However, the opening <NUM> may have the size that does not allow insertion of the cells <NUM>. Preferably, the fixation member <NUM> is formed of resin or rubber, and more preferably, PET film. The material for forming the thread <NUM> is not specifically limited. Preferably, however, the thread <NUM> is resistant to the temperature rise owing to heat dissipation from the cell <NUM>. The thread <NUM> is preferably used for sewing the heat dissipating members <NUM> on the two opposite sides using a sewing machine or the like. Stitching for sewing with the thread <NUM> is not specifically limited. An arbitrary stitching may be selectively used from hand stitching, final stitching, zigzag stitching, single chain stitching, double chain stitching, hem stitching, flat stitching, safety stitching, overlock stitching and the like. The stitching may also be selected from those prescribed by JIS L <NUM> as codes of "<NUM>", "<NUM>", "<NUM>", "<NUM>", "<NUM>", "<NUM>", "<NUM>", "<NUM>", "<NUM>", "<NUM>", "<NUM>", "<NUM>", "<NUM>", "<NUM>", "<NUM>", "<NUM>", "<NUM>", and "<NUM>".

In the heat dissipating structure <NUM>, the heat dissipating members <NUM> are fixed to the fixation member <NUM> while being allowed to be positioned and connected. In order to achieve high heat conduction efficiency, each of the cells <NUM> is required to dissipate heat uniformly for making each temperature of the cells <NUM> uniform. Preferably, the plurality of heat dissipating members <NUM> are arranged so that the number of the heat dissipating members <NUM> in contact with the cells <NUM> is made uniform. As the heat dissipating members <NUM> are positioned with the fixation member <NUM>, the heat dissipating structure <NUM> ensures that the heat dissipating members <NUM> contact the cells <NUM>. As a result, the heat dissipating structure <NUM> may enhance uniformity in heat dissipation from the cells <NUM>, resulting in high thermal conduction efficiency. The material for forming the fixation member <NUM> is not limited to the resin or the rubber so long as it is not deformed owing to heat dissipation from the cell <NUM>. For example, the fixation member <NUM> may be formed of such material as metal, plastic, wood, and ceramics. It is possible to fix only one longitudinal end of each of the heat dissipating member <NUM> to one side of the frame <NUM>.

Upon reception of pressure force from the cell <NUM>, the heat dissipating members <NUM> are crushed to reduce a distance L1 therebetween. If the heat dissipating members <NUM> are hardly crushed, there may cause the risk of deteriorating adhesiveness between the heat conduction sheet <NUM> and the cells <NUM>, and the heat conduction sheet <NUM> and the bottom <NUM>. The above-described risk may be reduced by setting the thickness of the heat dissipating member <NUM> in the height direction to be under the vertical pressure force from the bottom of the cell <NUM> to the surface of the bottom <NUM> to at least <NUM>% of the cross section diameter of the heat dissipating member <NUM> (= circular conversion diameter : D). The term "circular conversion diameter" refers to a diameter of a perfect circle with the same area as that of the cross section of the heat dissipating member <NUM> to be cut perpendicularly to the longitudinal direction. If the heat dissipating member <NUM> is formed into a cylindrical structure having the cross section formed into the perfect circle, the diameter is equal to the circular conversion diameter. Upon reception of the pressure force, the heat dissipating member <NUM> can be assumed to deform to have flat surfaces in contact with the cell <NUM> and the bottom <NUM>, and an arc-like section along the distance L1 between the heat dissipating members <NUM> (see <FIG>). When the heat dissipating member <NUM> is crushed to have a thickness of <NUM>. 8D corresponding to <NUM>% of the circular conversion diameter D, the resultant extension amount of the heat dissipating member <NUM> in the direction of the distance L1 is calculated. Referring to <FIG>, the total extension length of the arc-like sections of the crushed heat dissipating member <NUM> at left and right sides is <NUM>. The length of the flat surface in contact with the bottom <NUM> is half the length derived from subtracting the total extension length of the arc-like sections from the circumference of cross section of the heat dissipating member <NUM> as follows: (πD - <NUM>. 8πD)/<NUM> =<NUM>. The length of the arc-like sections extending leftward and rightward along the flat surface is calculated as follows: <NUM>. 4D x <NUM> = <NUM>. The length of the crushed heat dissipating member <NUM> extending from the original state in the direction of the distance L1 is calculated as follows: <NUM>. 314D + <NUM>. 8D - D = <NUM>. The sufficiently long distance L1 prevents the contact between the adjacent heat dissipating members <NUM>. Conversely, excessively short distance L1 may bring the adjacent heat dissipating members <NUM> into contact with each other, and prevent them from being further crushed even under the vertically compressed state. The distance L1 set to <NUM>% of the circular conversion diameter D of the heat dissipating member <NUM> or longer prevents the contact between the adjacent heat dissipating members <NUM> when they are deformed under pressure force to have the thickness <NUM>% of the circular conversion diameter D. This makes it possible to prevent the contact state from being obstacle to further deformation of the heat dissipating members <NUM>. In this embodiment, the distance L is set to <NUM>.

Preferably, the fixation member <NUM> is formed to have a thickness T smaller than the thickness (<NUM>. 8D) of the heat dissipating member <NUM> that has been deformed under pressure force from the cell <NUM> (see <FIG>). The above-formed heat dissipating structure <NUM> reduces the risk that the contact between the cell <NUM> and the fixation member <NUM> prevents further crushing of the heat dissipating member <NUM> vertically compressed by the cell <NUM>. This makes it possible to prevent the contact state from being obstacle to further deformation of the heat dissipating member <NUM> compressed and deformed to have a thickness corresponding to <NUM>% of the circular conversion diameter D. As both longitudinal ends of the heat dissipating member <NUM> are fixed onto the fixation member <NUM>, those ends never come in contact with the bottom <NUM> of the housing <NUM>. As the other region of the heat dissipating member <NUM> between both ends comes in contact with the bottom <NUM>, sufficient heat dissipating effect may be obtained. Preferably, the surface of the heat dissipating member <NUM> closer to the bottom <NUM> is at the same level as the surface of the fixation member <NUM> closer to the bottom <NUM>, or slightly protruding toward the bottom <NUM> so that the fixation member <NUM> easily comes in contact with the bottom <NUM>.

In the heat dissipating structure <NUM>, the both longitudinal ends (in direction Y of <FIG>) of each of the heat dissipating members <NUM> are sewn and fixed onto the fixation member <NUM> with the thread <NUM>. The both ends of the heat dissipating member <NUM> fixed to the fixation member <NUM> are compressed by the cell <NUM>, and crushed. The heat conduction sheet <NUM> may come in well contact with the non-flat lower ends of the cells <NUM> appropriately. In the heat dissipating structure <NUM>, the region of the heat dissipating member <NUM> other than the both ends fixed to the fixation member <NUM> is compressed by the cell <NUM>, and crushed. The heat dissipating structure <NUM> is preferably formed to allow the cells <NUM> to come in contact with the region of the heat dissipating member <NUM> other than the both ends fixed to the fixation member <NUM>. Even when the heat dissipating members <NUM> positioned with the fixation member <NUM> are compressed and crushed by the cells <NUM>, variation in values of the distance L1 between the heat dissipating members <NUM> is reduced. This makes it possible to enhance uniformity in heat dissipation from the cells <NUM>. Arrangement of the heat dissipating members <NUM> is not limited to the one at an equal interval of the distance L1. Preferably, the heat dissipating structure <NUM> is formed to change the distance L1 between the heat dissipating members <NUM> so that the heat dissipating members <NUM> are disposed concentratedly at the position corresponding to the cell <NUM> at higher temperature among them. Preferably, the heat dissipating structure <NUM> is formed to reduce the distance L1 between the heat dissipating members <NUM> to be in contact with the high temperature cells <NUM> so that more heat dissipating members <NUM> come in contact with the high temperature cells <NUM> than those in contact with other cells <NUM>. This allows the battery <NUM> to further enhance uniformity in heat dissipating property among the cells <NUM>.

Preferably, the heat conduction oil contains silicone oil, and a heat conduction filler that exhibits higher heat conductivity than the silicone oil, and is composed of at least one of metal, ceramics, and carbon. The heat conduction sheet <NUM> includes a gap (hole or recess portion) on a microscopic level. Normally, air existing in the gap may exert adverse influence on the heat conductivity. The heat conduction oil is filled in the gap to remove air to enhance heat conductivity of the heat conduction sheet <NUM>.

The heat conduction oil is applied to the surface of the heat conduction sheet <NUM>, specifically, at least the surface on which the cells <NUM> come in contact with the heat conduction sheet <NUM>. In the present invention, the "oil" of the heat conduction oil refers to a water-insoluble combustible substance in either liquid or semi-solid form at normal temperature (arbitrary temperature in the range from <NUM> to <NUM>). It is possible to use the term "grease" or "wax" in place of the term "oil". The heat conduction oil hardly becomes the obstacle to heat conduction upon heat transfer from the cell <NUM> to the heat conduction sheet <NUM>. A hydrocarbon based oil and the silicone oil may be used for forming the heat conduction oil. Preferably, the heat conduction oil contains the silicone oil, and the heat conduction filler that exhibits higher heat conductivity than the silicone oil, and is composed of at least one of metal, ceramics, and carbon.

Preferably, the silicone oil is composed of particles having siloxane bond of <NUM> or less with linear chain structure. The silicone oil has two types of straight silicone oil and modified silicone oil. The straight silicone oil includes dimethyl silicone oil, methylphenyl silicone oil, and methyl hydrogen silicone oil. The modified silicone oil includes reactive silicon oil and non-reactive silicone oil. The reactive silicone oil includes various types 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 types such as polyether modified type, methylstyryl modified type, alkyl modified type, higher fatty acid ester modified type, hydrophilic specific modified type, higher fatty acid contained type, and fluorine modified type. Because of properties excellent in heat resistance, cold resistance, viscosity stability, and heat conductivity, the silicone oil is applied to the surface of the heat conduction sheet <NUM> to serve as the heat conduction oil especially suitable for intervening between the cell <NUM> and the heat conduction sheet <NUM>.

Preferably, the heat conduction oil contains the heat conduction filler composed of at least one of metal, ceramics, and carbon besides the oil content. Gold, silver, copper, aluminum, beryllium, tungsten and the like are exemplified as metal. Alumina, aluminum nitride, cubic boron nitride, hexagonal boron nitride, and the like are exemplified as ceramics. Diamond, graphite, diamond-like carbon, amorphous carbon, carbon nanotube are exemplified as carbon.

Preferably, the heat conduction oil intervenes between the heat conduction sheet <NUM> and the housing <NUM> besides the intervention between the cell <NUM> and the heat conduction sheet <NUM>. The heat conduction oil may be applied to the surface of the heat conduction sheet <NUM> entirely or partially. Application of the heat conduction oil to the heat conduction sheet <NUM> is not necessarily limited to the specific method. The heat conduction oil may be applied arbitrarily by, for example, atomization using the spray, application using the brush or the like, immersion of the heat conduction sheet <NUM> in the heat conduction oil, and the like. Preferably, the heat conduction oil is used as an element to be suitably added to the heat dissipating structure <NUM> or the battery <NUM> rather than as the requisite element therefor. This applies to a second and subsequent embodiments.

<FIG> are explanatory views of a part of a process of forming the heat dissipating structure of <FIG>.

First, the cushion member <NUM> is formed. While the cushion member <NUM> is in the uncured state before it is completely cured, the belt-like heat conduction sheet <NUM> is spirally wound around an outer surface of the cushion member <NUM>. The cushion member <NUM> is then completely cured in heating. Portions of the belt-like heat conduction sheet <NUM>, protruding from both ends of the cushion member <NUM> are cut. Finally, the heat conduction oil is applied to the surface of the heat conduction sheet <NUM>. In forming the heat dissipating member <NUM> as described above, the uncured cushion member <NUM> enters into the gap on the microscopic level generated in the heat conduction sheet <NUM>, and then cured therein. This makes it possible to firmly fix the heat conduction sheet <NUM> to the cushion member <NUM> without using the adhesive agent.

The formed heat dissipating member <NUM> protrudes from the outer surface of the cushion member <NUM> by the amount corresponding to the thickness of the heat conduction sheet <NUM>. The heat conduction sheet <NUM> may be flush with the cushion member <NUM>. The heat conduction oil may be applied to the surface of the heat conduction sheet <NUM>, at least on the region in contact with the cell <NUM>. Each timing for executing the process of cutting the heat conduction sheet <NUM> protruding from both sides of the cushion member <NUM>, and the process of applying the heat conduction oil is arbitrarily set without being limited to the timing as described above. Those processes may be executed at arbitrary timings so long as they are executed after winding the heat conduction sheet <NUM> around the cushion member <NUM>. The heat conduction sheet <NUM> may be wound around the outer surface of the cushion member <NUM> in the completely cured state. If the outer surface of the cushion member <NUM> is not adhesive, the heat conduction sheet <NUM> may be fixed to the cushion member <NUM> using the adhesive agent.

The heat dissipating structure <NUM> is formed in the following process. The formed heat dissipating members <NUM> are orthogonally arranged to the winding direction of the heat conduction sheet <NUM> (longitudinal direction of the heat dissipating member <NUM>), and connected by the connection member <NUM> while being sewn on the fixation member <NUM> with the thread <NUM>. More specifically, the heat dissipating structure <NUM> is formed by connecting the arranged heat dissipating members <NUM> with the thread as the connection member <NUM> through manual sewing. Preferably, the heat dissipating members <NUM> are arranged at each distance L1 therebetween set to <NUM>. 114D or longer (see <FIG>). Preferably, the sewing is performed to form the twisted portion <NUM> between the heat dissipating members <NUM>. In the heat dissipating structure <NUM>, both longitudinal ends of each of the heat dissipating members <NUM> are preferably sewn on the frame <NUM> with the thread <NUM> using the sewing machine. The heat dissipating structure <NUM> allows positioning of the heat dissipating members <NUM> while being fixed to the fixation member <NUM>.

In the heat dissipating structure <NUM> having the blind-like connected heat dissipating members <NUM>, under the pressure force from the cell <NUM>, the heat dissipating member <NUM> is crushed to be vertically and horizontally expanded following the surface of the cell <NUM>. When the cells <NUM> are removed, elastic force of the heat dissipating member <NUM> restores its original shape. The heat dissipating structure <NUM> allows the blind-like connected heat dissipating members <NUM> to be positioned by the fixation member <NUM>. This reliably brings the heat dissipating members <NUM> into contact with the cells <NUM>. The heat dissipating structure <NUM> may prevent the heat dissipating members <NUM> from being unevenly distributed owing to vibration of the automobile, and enhance uniformity in heat dissipating among the cells <NUM>. In the heat dissipating structure <NUM>, as each of the heat dissipating members <NUM> has the heat conduction sheet <NUM> spirally wound around the outer surface of the cushion member <NUM>, the cushion member <NUM> will not excessively restrain deformation of the cushion member <NUM>. The frame <NUM> of the fixation member <NUM> allows the operator to mount the heat dissipating structure <NUM> in the battery <NUM> while manually holding the frame <NUM>, thus improving operability.

A heat dissipating structure according to a second embodiment, and a battery provided with the heat dissipating structure are described. Portions common with those of the first embodiment are denoted by the same reference numerals, and redundant description is omitted.

<FIG> is a plan view of the heat dissipating structure according to the second embodiment. <FIG> is a sectional view taken along line F-F of <FIG> is an enlarged view of a region G of <FIG>.

Unlike the heat dissipating structure <NUM> of the first embodiment, a heat dissipating structure 25a of the second embodiment has the plurality of heat dissipating members <NUM> connected by connection members 35a. Other configuration except the connection member 35a is common with that of the first embodiment, and an explanation thereof, thus is omitted.

Likewise the connection member of the first embodiment, the connection member 35a is formed of the thread or the rubber as the material partially deformable at a region at least between the heat dissipating members <NUM>. In this embodiment, the connection member 35a is preferably formed of the thread, and more preferably formed of the thread sufficient to resist the temperature rise owing to heat dissipation from the cell <NUM>. The connection member 35a is used for sewing the heat dissipating members <NUM> using the sewing machine or the like. An arbitrary stitching for forming the connection member 35a may be selectively used from hand stitching, final stitching, zigzag stitching, single chain stitching, double chain stitching, hem stitching, flat stitching, safety stitching, overlock stitching, and the like. The stitching may also be selected from those prescribed by JIS L <NUM> as codes of "<NUM>", "<NUM>", "<NUM>", "<NUM>", "<NUM>", "<NUM>", "<NUM>", "<NUM>", "<NUM>", "<NUM>", "<NUM>", "<NUM>", "<NUM>", "<NUM>", "<NUM>", "<NUM>", "<NUM>", and "<NUM>". Unlike the connection member <NUM> of the first embodiment, the connection member 35a does not have the twisted portions <NUM> each interposed between the heat dissipating members <NUM>.

The heat dissipating structure 25a is formed in the following process. The formed heat dissipating members <NUM> likewise the first embodiment are orthogonally arranged to the winding direction of the heat conduction sheet <NUM>, and connected by the connection members 35a while being sewn on the fixation member <NUM> with the thread <NUM>. More specifically, the heat dissipating structure 25a is formed by connecting the arranged heat dissipating members <NUM> by the connection member 35a through sewing with the thread using the sewing machine or the like. The heat dissipating members <NUM> are arranged at each distance L2 smaller than the distance L1 (see <FIG>). Specifically, the distance L2 is set to the value <NUM>% (= <NUM>. 114D) of the circular conversion diameter D of the heat dissipating member <NUM>. Under the condition, the heat dissipating member <NUM> may be vertically crushed to have the thickness up to approximately <NUM>% of the circular conversion diameter D. By setting the distance L2 to <NUM>. 114D or longer, the heat dissipating member <NUM> never becomes the obstacle to deformation of the adjacent heat dissipating member <NUM> when they are crushed under pressure force to have each thickness equal to or smaller than <NUM>% of the circular conversion diameter. The shorter the distance L2 between the heat dissipating members <NUM> becomes, the more stable the connection between the heat dissipating members <NUM> becomes upon sewing using the sewing machine. The heat dissipating members <NUM> can be crushed to be vertically and horizontally expanded in a non-restricted manner while following and coming in tight contact with the surface of the cell <NUM> until they come in contact with each other. When the cells <NUM> are removed, the elastic force of the heat dissipating member <NUM> allows the heat dissipating structure 25a to have its original shape restored. The heat dissipating structure 25a having the heat dissipating members <NUM> blind-like connected restrains uneven distribution of the heat dissipating members <NUM> owing to vibration of the automobile, thus improving workability. Especially in the heat dissipating structure 25a, the heat dissipating members <NUM> are connected by the connection members 35a using the sewing machine. This improves workability when the number of the heat dissipating members <NUM> constituting the heat dissipating structure 25a becomes large.

A heat dissipating structure according to a third embodiment and a battery provided with the heat dissipating structure are described. Portions common with those of the embodiments are denoted by the same reference numerals, and redundant description is omitted.

<FIG> is a longitudinal sectional view of the heat dissipating structure according to the third embodiment, and a battery provided with the heat dissipating structure. <FIG> shows a part of a process of forming the heat dissipating structure of the third embodiment. <FIG> is a plan view of the heat dissipating structure formed by the process as shown in <FIG>.

A battery 1a according to the third embodiment includes a heat dissipating structure 25b different from the heat dissipating structure <NUM> disposed in the battery <NUM> according to the first embodiment, and has the other structure common with the battery <NUM>. The heat dissipating structure 25b used in this embodiment is formed by connecting a plurality of heat dissipating members 28a different from the heat dissipating members <NUM> of the first embodiment by the connection member <NUM>. The cushion member <NUM> of the heat dissipating member 28a is not cylindrically shaped, but is belt-like shaped to be applied to the back side of the heat conduction sheet <NUM>. The cushion member <NUM> is spirally wound together with the heat conduction sheet <NUM>.

A method of forming the heat dissipating structure 25b including the spiral cushion member <NUM> (referred to as "spiral cushion member <NUM>" or simply "cushion member <NUM>") is described below.

A laminated body <NUM> is formed to have two layers of the heat conduction sheet <NUM> and the cushion member <NUM> each having substantially the same width. The heat conduction oil is applied to the surface of the heat conduction sheet <NUM>. The laminated body <NUM> having the surface applied with the heat conduction oil is spirally (coil-like) wound in one direction. The long heat dissipating member 28a may be formed by spirally winding the laminated body <NUM>. The heat conduction oil may be applied to the heat conduction sheet <NUM> before forming the laminated body <NUM>, or in the final step. Preferably, the heat conduction sheet <NUM> is laminated onto the cushion member <NUM> in the uncured state before it is completely cured. The cushion member <NUM> is then heated to be completely cured so that the laminated body <NUM> is formed.

The heat dissipating members 28a are orthogonally arranged to the winding direction (longitudinal direction of the heat dissipating member 28a) of the heat conduction sheet <NUM>, and connected by the connection member <NUM>. They are further sewn on the fixation member <NUM> with the thread <NUM> to form the heat dissipating structure 25b.

The heat dissipating member 28a including a through passage <NUM> penetrating in the longitudinal direction is different from the heat dissipating member <NUM> of the first embodiment in that the through passage <NUM> further extends toward the outer surface of the heat dissipating member 28a. The spirally shaped heat dissipating member 28a is more flexible in the longitudinal direction (in white arrow directions of <FIG>) than the heat dissipating member <NUM>.

The heat dissipating structure 25b can be disposed not only between the cells <NUM> and the bottom <NUM> of the housing <NUM>, but also in gaps between the cells <NUM> and an inner side surface of the housing <NUM>, and/or in gaps between the cells <NUM>.

The heat dissipating structures <NUM>, 25a, 25b (to be collectively and representatively referred to as the "heat dissipating structure <NUM>") are formed by connecting the plurality of heat dissipating members <NUM> or 28a, respectively for enhancing heat dissipation from the cells <NUM>, as described above. The heat dissipating members <NUM>, 28a include the heat conduction sheets <NUM>, the cushion members <NUM>, and the through passages <NUM>, <NUM>, respectively. The heat conduction sheet <NUM> is spirally winding to conduct heat from the cell <NUM>. The cushion member <NUM> is provided on the annular back surface of the heat conduction sheet <NUM>, and deformable following the surface shape of the cell <NUM> more easily than the heat conduction sheet <NUM>. The through passages <NUM>, <NUM> penetrate in the winding direction of the heat conduction sheet <NUM>. The heat dissipating structure <NUM> includes the fixation member <NUM> on which the heat dissipating members <NUM> or 28a are orthogonally arranged to the longitudinal direction for fixing at least each one longitudinal end of the heat dissipating members <NUM> or 28a.

The heat dissipating structure <NUM> is adaptable to various forms of the cell <NUM>, excellent in elastic deformability and heat dissipating efficiency, and capable of enhancing uniformity in heat dissipation among the cells <NUM>. The through passage <NUM> or <NUM> contributes to weight reduction in the heat dissipating structure <NUM>.

The fixation member <NUM> that constitutes the heat dissipating structure <NUM> is formed to surround the heat dissipating members <NUM> or 28a orthogonally arranged to the longitudinal direction thereof. This allows the operator to mount the heat dissipating structure <NUM> in the battery <NUM> or 1a while holding the fixation member <NUM>, thus improving operability.

The fixation member <NUM> constituting the heat dissipating structure <NUM> is formed to have a thickness T smaller than the thickness of the heat dissipating member <NUM> or 28a deformed under the pressure force from the cell <NUM>. The heat dissipating structure <NUM> prevents the contact between the cell <NUM> and the fixation member <NUM> from being the obstacle to further crushing of the heat dissipating members <NUM> vertically compressed by the cell <NUM>.

The cushion member <NUM> constituting the heat dissipating structure <NUM> is cylindrically shaped to have the through passage <NUM> penetrating in the longitudinal direction. The heat conduction sheet <NUM> is spirally wound around the outer surface of the cylindrical cushion member. The batteries <NUM>, 1a include the heat dissipating structures <NUM> in contact with the cells <NUM> inside the housings <NUM>, respectively. The heat conduction sheet <NUM> partially covers the outer surface of the cylindrical cushion member, and is spirally winding around the cylindrical cushion member in the longitudinal direction. In the batteries <NUM>, 1a, the heat dissipating structures <NUM> are respectively disposed at least between the cells <NUM> and the cooling agent <NUM>. Therefore, the heat dissipating structure <NUM> is unlikely to be constrained by the heat conduction sheet <NUM>, and is deformable following recess and protruding portions on the surface of the cell <NUM>.

In the heat dissipating structure 25b, the cushion member <NUM> is spirally wound along the annular back surface of the heat conduction sheet <NUM>. In the battery 1a, the heat dissipating structure 25b is disposed at least between the cells <NUM> and the cooling agent <NUM>. The heat dissipating structure 25b may be disposed between the inner side surface of the housing <NUM> and the cells <NUM>, and/or between the cells <NUM>. The heat dissipating structure 25b is spirally shaped entirely, and therefore is more adaptable to various sizes of the cell <NUM>. Specifically, the highly rigid heat conduction sheet <NUM> is deformable under low load to follow and comes in close contact with the surface of the cell <NUM>. Furthermore, even if the deformation amount partially differs, the adhesiveness and follow-up property may be improved. As the cushion member <NUM> is spirally cut, the single spiral portion may be deformed separately. Therefore, the heat dissipating structure 25b may enhance flexibility in local deformation. In addition, the heat dissipating structure 25b includes not only the through passage <NUM>, but also a spiral through groove extending from the through passage <NUM> to the side surface, resulting in weight reduction.

The connection members <NUM>, 35a connect the heat dissipating members <NUM>, 28a orthogonally arranged to the longitudinal direction thereof, respectively. The connection members <NUM>, 35a are formed of threads. The heat dissipating structure <NUM> is formed by connecting the heat dissipating members <NUM> or 28a in the blind-like manner. This makes it possible to restrain uneven distribution of the heat dissipating members <NUM> or 28a owing to vibration of the automobile or the like, thus improving workability.

The connection members <NUM>, 35a include the twisted portions <NUM> interposed between the heat dissipating members <NUM>, 28a, respectively to further enhance the follow-up property and adhesiveness with the surface of the cell <NUM>.

The heat conduction oil is applied to the surface of the heat conduction sheet <NUM> for enhancing heat conduction to the surface from the cell <NUM> in contact therewith. The heat conduction sheet <NUM> includes gaps (holes or recess portions) on the microscopic level. Normally, air existing in the gap may exert adverse influence on heat conductivity. The heat conduction oil is filled in the gap to remove air, and further enhance heat conductivity of the heat conduction sheet <NUM>.

The heat conduction oil contains the silicone oil and the heat conduction filler that exhibits higher heat conductivity than the silicon oil, and is composed of at least one of metal, ceramics and carbon. The silicone oil is excellent in heat resistance, cold resistance, viscosity stability, and heat conductivity. Especially, the heat conduction oil is suitably applied to the surface of the heat conduction sheet <NUM> to intervene between the cell <NUM> and the heat conduction sheet <NUM>. The heat conduction filler contained in the heat conduction oil serves to enhance heat conductivity of the heat conduction sheet <NUM>.

Each of the batteries <NUM>, 1a includes one or more cells <NUM> as heat sources in the housing <NUM> that allows flow of the cooling agent <NUM>, and further includes the heat dissipating structure <NUM>. In the heat dissipating structure <NUM>, each of the connectedly arranged heat dissipating members <NUM>, 28a includes the heat conduction sheet <NUM> spirally winding for conducting heat from the cell <NUM>, the cushion member <NUM> that is provided on the annular back surface of the heat conduction sheet <NUM>, and deformable following the surface shape of the cell <NUM> more easily than the heat conduction sheet <NUM>, and the through passage <NUM> or <NUM> penetrating in the winding direction of the sheet conduction sheet <NUM>. The heat dissipating structure <NUM> includes the fixation member <NUM> capable of fixing at least one longitudinal end of each of the heat dissipating members <NUM>, 28a orthogonally arranged to the longitudinal direction thereof. The above-structured batteries <NUM>, 1a are adaptable to various forms of the cells <NUM>, excellent in elastic deformability and heat dissipating efficiency, and capable of enhancing uniformity in heat dissipation among the cells <NUM>. The through passage <NUM> or <NUM> contributes to weight reduction in the heat dissipating structure <NUM>.

The preferred embodiments of the present invention have been described. However, the present invention is not limited to those embodiments, and may be variously modified for implementation.

<FIG> is a sectional view of the heat dissipating structure on which cells are placed transversely having each one side surface in contact with the heat dissipating structure. <FIG> is a partially enlarged view of <FIG> is a sectional view of <FIG> partially showing the cell expanded in charging-discharging.

In the aforementioned embodiments, the cells <NUM> are vertically placed, having each lower end in contact with the heat dissipating structure <NUM>. The cells may be arbitrarily placed without being limited to the arrangement as described above. As <FIG> shows, the cells <NUM> may be placed to allow the respective one side surfaces to come in contact with the respective heat dissipating members <NUM> or 28a of the heat dissipating structure <NUM>. The cell <NUM> has its temperature increased in charging and discharging. The use of the highly flexible material for forming the container of the cell <NUM> may expand especially the side surface of the cell <NUM>. However, as shown in <FIG>, the heat dissipating members <NUM> or 28a constituting the heat dissipating structure <NUM> are deformable following the outer surface of the cell <NUM>. This maintains high heat dissipating property even in charging and discharging.

For example, the heat source includes not only the cells <NUM> but also all heat generating elements such as a circuit board and an electronic device body. For example, the heat source may be an electronic component such as a capacitor and an IC chip. Similarly, the cooling agent <NUM> may be not only cooling water but also organic solvent, liquid nitrogen, and cooling gas. The heat dissipating structure <NUM> may be disposed in structures other than the battery <NUM> and the like, for example, electronic devices, home electric appliances, and power generators.

The heat dissipating members <NUM> or 28a constituting the heat dissipating structure <NUM> may have only longitudinal one ends fixed to the fixation member <NUM>. The heat dissipating structure <NUM> may have four sides constituting the inner periphery of the frame <NUM> of the fixation member <NUM> connected to the heat dissipating members <NUM> or 28a with the thread <NUM>. In the heat dissipating structure <NUM>, both longitudinal ends of each of the heat dissipating members <NUM> or 28a are fixed to the fixation member <NUM> as described in the embodiments. Additionally, it is also possible to further fix the heat dissipating members <NUM> or 28a positioned at both sides in the direction (width direction) orthogonal to the longitudinal direction of those arranged in the heat dissipating structure <NUM> to two parallel opposite sides of the four sides constituting the inner periphery of the frame <NUM>.

The fixation member <NUM> may be formed into an arbitrary shape with no limitation so long as at least each one longitudinal end of the heat dissipating members <NUM> or 28a has a fixable shape. For example, the fixation member <NUM> may be formed as one or more long members rather than the shape of the frame <NUM>. Instead of the rectangular frame-like member, the frame <NUM> may be formed to have an outer shape of ellipse, circle, triangle, or polygon equal to or more than pentagon in a planar view while having the opening <NUM> therein. In the respective embodiments, the frame <NUM> is fixed to the heat dissipating members <NUM> so that the surface of the frame <NUM> closer to the bottom <NUM> is positioned at the same level as the surface of the heat dissipating member <NUM> closer to the bottom <NUM>. The heat dissipating member <NUM> may be fixed to the frame <NUM> so that the surface of the frame <NUM> closer to the cell <NUM> is positioned at the same level as the surface of the heat dissipating member <NUM> closer to the cell <NUM>. The frame <NUM> may be fixed to an intermediate position of the heat dissipating member <NUM> in the height direction (direction from the cell <NUM> toward the bottom <NUM>).

The heat dissipating structure <NUM> does not have to include the connection members <NUM> or 35a. Preferably, both longitudinal ends of each of the heat dissipating members <NUM> or 28a constituting the heat dissipating structure <NUM> are fixed to the fixation member <NUM> by adhesion, fitting, or the like. In this case, the fixation member <NUM> serves to position and connect the heat dissipating members <NUM> or 28a of the heat dissipating structure <NUM>.

The width of the spirally shaped cushion member <NUM> of the heat dissipating member 28a does not have to be the same as the width of the heat conduction sheet <NUM>, but may be either larger or smaller. In the embodiments, the through passage <NUM> is formed in the cushion member <NUM>. However, the through passage <NUM> does not have to be formed in the cushion member <NUM>. In this case, the heat dissipating member <NUM> is structured to have the through passage of the spiral heat conduction sheet <NUM> filled with the cushion member <NUM>. The through passage <NUM> does not have to be formed in the cushion member <NUM> so long as it is formed in any one of the heat conduction sheet <NUM> and the cushion member <NUM>, at least in the winding structure of the heat conduction sheet <NUM>.

A plurality of components of each of the embodiments can be freely combined except those regarded as impossible. For example, the heat dissipating structure 25b according to the third embodiment may be disposed in place of the heat dissipating structure <NUM> according to the first embodiment.

Claim 1:
A heat dissipating structure (<NUM>) comprising a plurality of heat dissipating members (<NUM>) connected for enhancing heat dissipation from a heat source and a fixation member (<NUM>), characterized in that each of the heat dissipating members (<NUM>) comprises
a heat conduction sheet (<NUM>) in a spirally winding shape for conducting heat from the heat source,
a cushion member (<NUM>) provided on an annular back surface of the heat conduction sheet (<NUM>), the cushion member (<NUM>) being deformable following a surface shape of the heat source more easily than the heat conduction sheet (<NUM>), and
a through passage (<NUM>) penetrating in a winding direction of the heat conduction sheet (<NUM>),
wherein the fixation member (<NUM>) fixes the heat dissipating members (<NUM>), is orthogonally arranged to a longitudinal direction of the heat dissipating member (<NUM>) and fixes at least one longitudinal end of each of the heat dissipating members (<NUM>), and includes a frame (<NUM>) that surrounds the heat dissipating members (<NUM>) both in the longitudinal direction and a direction in which the heat dissipating members (<NUM>) are arranged.