JP2012104284A - Housing structure of power storage device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To ensure good heat dissipation of the housing structure for a power storage device (10) by a half-cut case (1) in which dimensional variation in the case (1) or the power storage device (10) causes no trouble in the sealing of the mating surface of the case.SOLUTION: The half-cut case (1) is configured by fitting a pair of resin case members (2) having thermal conductivity and electric insulation. An elastic sheet (11) having thermal conductivity and electric insulation is interposed between a power storage device (10) and the inner wall surface of each case member (2). A plurality of protrusions (12) which bite into the elastic sheet (11) and press the elastic sheet (11) against the power storage device (10) are provided on the inner wall surface of each case member (2).

Description

  The present invention relates to a housing structure for a power storage device such as a secondary battery or a capacitor (capacitor).

  This type of power storage device generates heat during charging and discharging, and causes deterioration of the power storage device when the high temperature state continues. In particular, since a power storage device for an automobile is used in such a way that a large current flows instantaneously, deterioration due to a temperature rise of the power storage device becomes a problem.

  With respect to this problem, Patent Document 1 relates to a battery pack used in a mode of performing high-rate discharge (rapid discharge), and a gel-like high heat conduction between the outer peripheral surface of the battery cell and the inner surface of the case that accommodates the battery cell. It is described that it is filled with a resin body. The heat generated in the battery cell is released from the outer peripheral surface of the battery cell to the case via the gel-like high thermal conductive resin. The case is of a half type that is configured by combining a pair of case members. Each half-case member is provided with a rib for holding the battery cell away from the inner surface of the case. Then, each half case member is filled with an appropriate amount of liquid high thermal conductive resin, heated and gelled, and in this state, the battery cell is sandwiched between both half case members, and the case members are joined together. It has become.

JP 2005-310449 A

  According to the battery pack, although heat dissipation of the power storage device such as a battery cell can be achieved by the gel-like high heat conductive resin, it is necessary to appropriately manage the filling amount of the liquid high heat conductive resin to be gelled.

  That is, if the filling amount of the liquid high thermal conductive resin is increased to some extent, the half case members cannot be firmly combined. In that case, moisture may enter the case from the gap between the half case members, and the moisture may cause corrosion of the power storage device or short circuit of the electrical terminals. In addition, if the power storage device uses an electrolytic solution, there is a possibility that harmful gas is generated by the reaction between the electrolytic solution and moisture. On the other hand, when the filling amount of the liquid high heat conductive resin is somewhat small, a gap is formed between the power storage device and the gel high heat conductive resin, and the heat dissipation is deteriorated.

  Accordingly, it is necessary to appropriately manage the filling amount of the liquid high thermal conductive resin. However, when the half case member is molded from a synthetic resin, it is necessary to avoid slight variations in the dimensions of the obtained case members. I can't. For example, when the resin pressure and the resin temperature in the mold are not uniform, the shrinkage amount of each part of the case member is different, so that the dimension between the case members varies. Or in the case of taking many, the dimension of a case member will vary a little due to the size variation of each cavity. Such dimensional variations are usually observed not only on the case side but also on the power storage device side. For this reason, there is a problem that it is difficult to control the filling amount of the liquid high thermal conductive resin and it is difficult to improve the quality.

  Therefore, the present invention relates to a housing structure for a power storage device in which a case is halved, and even when there is a dimensional variation in the case or the power storage device, good heat dissipation without causing trouble in sealing the case mating surface It is an issue to be able to ensure.

  In order to solve the above-described problems, the present invention aims to radiate heat from the power storage device by using an elastic sheet having heat conductivity and protrusions on the inner surface of the case.

That is, the storage structure for the power storage device presented here is a structure for storing the power storage device (10) in the case (1),
An elastic sheet (11) having heat conductivity and electrical insulation interposed between the power storage device (10) and the inner wall surface of the case (1),
The case (1) is a half type formed by combining a pair of shell-like resin case members (2) having heat conductivity and electrical insulation,
A plurality of protrusions (12) are provided on the inner wall surface of each of the case members (2) to bite into the elastic sheet (11) and press the elastic sheet (11) against the power storage device (10). Features.

  It is preferable to provide a plurality of radiating fins (7) on the outer wall surface of the case (1). In that case, a plurality of protrusions (12) protruding inwardly in the case (1) as the protrusions are provided on the inner wall surface of the case (1), and each of the plurality of protrusions (12) on the inner wall surface of the case (1) Preferably, the case (1) and the plurality of radiating fins (7) on the outer wall surface are arranged so as to correspond to each other inside and outside.

  Furthermore, it is preferable that the case (1) is formed of a synthetic resin containing a highly heat conductive needle filler (15). In that case, it is preferable that at least a part of the needle-like filler (15) is oriented in the protruding direction of the fin (7) in at least the portion of the heat radiating fin (7) of the case (1).

  According to the present invention, the heat generated in the power storage device (10) is transferred to the protrusion (12) of the case (1) via the elastic sheet (11) having heat conductivity, and escaped from the outer wall surface of the case (1). It is. Since the protrusion (12) of the case (1) bites into the elastic sheet (11), the contact area (heat transfer area) between the elastic sheet (11) and the case (1) can be increased. This is advantageous for heat dissipation of the power storage device (10). Moreover, since the protrusion (12) is in a state where the elastic sheet (11) is pressed against the power storage device (10), the power storage device (10) is securely held in the case (1) without being displaced, and is resistant to vibration. Durability is also increased.

  Thus, even if the case (1) has a dimensional variation, the variation is absorbed by the elastic deformation of the elastic sheet (11), so that the assembly of the case members (2) is not hindered. That is, even if there is a variation in the dimensions described above, the amount of protrusion (12) biting into the elastic sheet (11) is slightly changed, and there is little effect on heat dissipation, and the mating surface between the case members (2) Can be reliably sealed.

  Providing heat radiating fins (7) on the outer wall surface of the case (1) is advantageous for improving the heat dissipation from the power storage device (10). In particular, a plurality of protrusions (12) are provided as protrusions on the inner wall surface of the case (1), and each of the protrusions (12) and the plurality of heat dissipating fins (7) on the outer wall surface of the case (1) are connected to each other. If the ridges (12) and the radiating fins (7) are closer to each other and the heat transfer distance is shortened, the heat transferred from the power storage device (10) to the ridges (12) It becomes easy to be transmitted to the radiating fin (7), and the heat is efficiently radiated. Further, the case (1) is formed of a synthetic resin containing the highly heat-conductive needle-like filler (15), and at least a part of the needle-like filler (15) protrudes from the fin (7) in the radiating fin (7). When oriented in the direction, the needle-like filler (15) efficiently conducts heat from the ridges (12) to the radiating fins (7), and the heat dissipation is further enhanced.

It is a perspective view which shows the case which accommodated the electrical storage apparatus which concerns on this invention. It is a disassembled perspective view which shows the storage structure of the electrical storage apparatus which concerns on this invention. It is a longitudinal cross-sectional view of the storage structure. It is the longitudinal cross-sectional view which expanded a part of the storage structure.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. The following description of the preferred embodiments is merely exemplary in nature and is not intended to limit the invention, its application, or its use.

  In FIG. 1, reference numeral 1 denotes a power storage device accommodation case. The housing case 1 is a half type, and includes a pair of shell-like case members 2 that form a tubular housing portion that is aligned with each other and closed at both ends. Both case members 2 are formed of a synthetic resin having heat conductivity (thermal conductivity) and electrical insulation, and are fastened via a seal packing 5. That is, both case members 2 are provided with flanges 4 projecting outward on the periphery of the semicylindrical housing portion 3, and the flanges 4 are fastened together by the screw members 6 with the packing 5 interposed therebetween. A plurality of radiating fins 7 extending in the cylinder circumferential direction are provided on the outer wall surface of the semicylindrical housing 3 at intervals in the cylinder axis direction. In FIG. 1, reference numeral 8 denotes a cable extending from the power storage device housed in the housing case 1.

  In FIG. 2, 10 is a cylindrical power storage device. The power storage device 10 is housed in the housing case 1 together with a pair of heat conductive and electrically insulating elastic sheets 11. As described above, the case member 2 is not only provided with the heat radiating fins 7 on the outer wall surface of the semicylindrical housing portion 3, but also has a plurality of protrusions 12 projecting inward from the case on the inner wall surface of the housing portion 3. Is provided. The protrusions 12 of this example are chevron-shaped, extend in the cylinder circumferential direction like the radiation fins 7, and are arranged in parallel in the cylinder axis direction.

  Then, as shown in FIG. 3, the plurality of heat radiation fins 7 and the plurality of protrusions 12 are arranged so as to correspond to each other inside and outside. In addition, each elastic sheet 11 is bent into a semi-cylindrical shape and is fitted in the accommodating portion 3 of each case member 2. In the housing case 1, both elastic sheets 11 wrap the power storage device 10 over the entire circumferential surface. Further, the ridge 12 of each case member 2 bites into the elastic sheet 11 leaving a space 16 between at least a portion between the adjacent ridges 12 (valley) of the case member 2 and the elastic sheet 11, The elastic sheet 11 is pressed against the power storage device 10. Positioning ribs 13 projecting inward from the case are provided on the walls at both ends in the cylinder axis direction of the housing portion 3 of each case member 2 to prevent the displacement of the power storage device 10 in the cylinder axis direction. The cable 8 of the power storage device 10 is extended to the outside through a through hole formed in the end face plate of one case member 2, and a seal 14 is provided in the through hole. In addition, a pair of case member 2 is comprised symmetrically except for the through-hole and the seal 14.

  As shown in FIG. 4, the case member 2 is formed of a synthetic resin containing a highly heat-conductive needle-like filler 15. In the portion of the ridge 12, a part of the needle-like filler 15 is oriented toward the base end portion of the radiating fin 7, and in the portion of the radiating fin 7, at least a part of the needle-like filler 15 is from the ridge 12. The radiating fins 7 are oriented in the protruding direction. Such orientation of the needle-like filler 15 can be obtained by adjusting the resin flow direction when the synthetic resin containing the needle-like filler 15 is poured into the case member molding die.

  For example, a gas venting part is provided over the entire length of the fin in the mold cavity where the heat dissipating fins 7 are molded, and the needle-like filler-containing resin molds the semi-cylindrical wall of the accommodating part 3 in the cavity. What is necessary is just to comprise a runner and a gate so that it may flow toward the other end side from the one end side of the part to perform (in the direction of the arrow A of FIG. 4). As a result, a part of the resin flows from a portion where each protrusion 12 is formed to a portion where the radiating fin 7 is formed, and the needle filler 15 is oriented as shown in FIG.

  As the synthetic resin having heat conductivity and electrical insulation that forms the case member 2 of the housing case 1, for example, ABS (acrylonitrile butadiene styrene resin), polyester, polypropylene, or the like can be employed. Polypropylene mixed with talc or glass fiber can also be preferably used. The needle-like filler 15 is formed of a high heat transfer material having better heat transfer than the synthetic resin, such as a metal oxide (for example, aluminum oxide, magnesium oxide) or a nitride (for example, boron nitride, aluminum nitride). To do.

  The elastic sheet 11 is preferably formed of, for example, silicone rubber having heat conductivity and electrical insulation, and in particular, like the housing case 1, a metal oxide (for example, aluminum oxide, magnesium oxide), a nitride (for example, nitriding) A material in which a highly heat conductive filler such as boron or aluminum nitride is mixed can be preferably used. The material of the elastic sheet 11 is not limited to silicone rubber, and may be, for example, an ethylene propylene-based polymer mixed with the heat conductive filler.

  According to the housing structure of the power storage device 10, the heat generated in the power storage device 10 is transmitted to the protrusions 12 of the housing case 1 via the elastic sheet 11, further transmitted to the heat radiating fins 7 and radiated to the outside.

  In the case of the present embodiment, since the two elastic sheets 11 are in a state of wrapping the entire circumferential surface of the power storage device 10, the heat transfer from the power storage device 10 to the elastic sheet 11 is good. And since the protrusion 12 bites into the elastic sheet 11, and the contact area of the storage case 1 and the elastic sheet 11 becomes large, the heat transfer property from the elastic sheet 11 to the protrusion 12 is good. Further, since the ridges 12 and the radiating fins 7 are arranged so as to correspond to the inside and outside, the ridges 12 and the radiating fins 7 are close to each other and the heat transfer distance is shortened. Heat transfer is performed efficiently. In addition, since the highly heat-conductive needle-like filler 15 is mixed in the housing case 1 and a part of the needle-like filler 15 is oriented from the ridge 12 side toward the tip of the radiating fin 7, the ridge. The heat transfer efficiency from 12 to the radiation fin 7 is improved.

  Further, since the protrusions 12 are in a state in which the elastic sheet 11 is pressed against the power storage device 10, the power storage device 10 is securely held in the housing case 1 without being displaced and the durability against vibration is increased. Thus, even if there are variations in the dimensions of the housing case 1 and the power storage device 10, the variations are absorbed by the elastic deformation of the elastic sheet. That is, the space 16 between the adjacent ridges 12 of the case member 2 becomes an escape portion that enters when the elastic sheet 11 is elastically deformed. Therefore, even if there is a variation in the dimensions, only the volume of the space 16 changes (only the amount of biting of the ridge (12) with respect to the elastic sheet (11) slightly changes), so that the case members 2 can be assembled together. Will not interfere. Therefore, it can be avoided that the mating surfaces of the case members 2 are poorly sealed. Therefore, the ingress of moisture into the housing case 1 can be surely stopped by the packing 5, preventing corrosion of the power storage device 10, preventing electrical terminals from being short-circuited, or preventing reaction between the electrolytic solution of the power storage device 10 and moisture (harmful) Gas generation prevention).

  In addition, although the electrical storage apparatus 10 of the said embodiment is cylindrical shape, square tube shape and another shape may be sufficient. The storage case 1 can also have a rectangular tube shape corresponding to the shape of the power storage device 10 or other shapes.

  Moreover, in the said embodiment, although the elastic sheet 11 covers only the surrounding surface of the electrical storage apparatus 10, you may further arrange | position the elastic sheet which covers the both end surfaces of the electrical storage apparatus 10. FIG.

  In the above embodiment, the power storage device 10 is wrapped around the entire circumferential surface by the pair of elastic sheets 11, but may be wrapped by a single elastic sheet.

  In the said embodiment, although the protrusion 12 is extended in the cylinder circumferential direction of the cylindrical storage case 1, the vertical protrusion extended in a cylinder axial direction may be sufficient. In that case, the heat radiating fins 7 can also extend in the cylinder axis direction so as to correspond to the vertical ridges. Moreover, it may replace with a protrusion and may provide many protrusions in the shape of a dot.

  In the above embodiment, both case members 2 are coupled by fastening with the screw member 6, but may be coupled with an adhesive, a molten resin, or the like.

DESCRIPTION OF SYMBOLS 1 Storage case 2 Case member 3 Storage part 4 Flange 5 Packing 6 Screw member 7 Radiation fin 8 Cable 10 Power storage device 11 Elastic sheet 12 Projection 13 Rib 14 Seal 15 Filler

Claims (4)

A structure for housing the power storage device (10) in the case (1),
An elastic sheet (11) having heat conductivity and electrical insulation interposed between the power storage device (10) and the inner wall surface of the case (1),
The case (1) is a half type formed by combining a pair of shell-like resin case members (2) having heat conductivity and electrical insulation,
A plurality of protrusions (12) are provided on the inner wall surface of each of the case members (2) to bite into the elastic sheet (11) and press the elastic sheet (11) against the power storage device (10). A storage structure for a power storage device, which is characterized. In claim 1,
A storage structure for a power storage device, wherein a plurality of heat radiation fins (7) are provided on an outer wall surface of the case (1). In claim 2,
The inner wall surface of the case (1) is provided with a plurality of protrusions (12) protruding inward of the case (1) as the protrusions, and the plurality of protrusions (12 on the inner wall surface of the case (1) ) A storage structure for a power storage device, wherein each case and each of the plurality of heat dissipating fins (7) on the outer wall surface of the case (1) correspond to each other inside and outside. In claim 3,
The case (1) is formed of a synthetic resin containing a highly heat conductive needle filler (15),
At least a part of the needle-like filler (15) is oriented in the protruding direction of the fin (7) in at least the portion of the heat radiating fin (7) of the case (1). Containment structure.

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