JP2018116821A - Battery module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a battery module in which heat dissipation of a battery can be easily improved.SOLUTION: A battery module 1 includes a heat exchanger 2, a thermal diffusion part 3, a heat conduction part 4, and a battery 5. The thermal diffusion part 3 is in thermal contact with the heat exchanger 2. The heat conduction part 4 is disposed on the top surface 31 of the thermal diffusion part 3. The battery 5 is in thermal contact with the top surface of the heat conduction part 4. The thermal diffusion part 3 has a higher thermal conductivity than the heat conduction part 4. The thermal diffusion part 3 has at least one hole 32 opening toward at least an upper side, at a position that overlaps the heat conduction part 4 in a vertical direction Z.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a battery module.

  An example of the battery module is disclosed in Patent Document 1. The battery module described in Patent Literature 1 includes a plurality of batteries arranged in one direction and a cooling plate arranged on the lower side in the vertical direction perpendicular to the arrangement direction of the plurality of batteries. The battery module described in Patent Document 1 has flexibility and thermal conductivity between the plurality of batteries and the cooling plate in order to improve thermal conductivity between the plurality of batteries and the cooling plate. A heat conductive sheet is interposed. In manufacturing the battery module, for example, the battery module can be manufactured by attaching a heat conductive sheet on the upper surface of the cooling plate and pressing a plurality of batteries on the upper surface of the heat conductive sheet.

JP 2013-84444 A

  However, in the battery module described in Patent Document 1, when the heat conductive sheet is attached to the upper surface of the cooling plate, there is a possibility that air, foreign matter, or the like may be trapped between the heat conductive sheet and the cooling plate. As a result, the thermal resistance from the battery to the cooling plate increases, and the heat dissipation of the battery may decrease.

  This invention is made | formed in view of this subject, and it aims at providing the battery module which is easy to improve the heat dissipation of a battery.

One aspect of the present invention is a heat exchanger (2),
A thermal diffusion section (3) in thermal contact with the heat exchanger;
A heat conducting part (4) disposed on an upper surface (31) of the heat diffusing part;
A battery (5) in thermal contact with the upper surface of the heat conducting part,
The thermal diffusion part has higher thermal conductivity than the thermal conduction part,
The said thermal diffusion part exists in a battery module (1) which has at least one hole (32) opened toward the upper side in the position which overlaps with the said heat conduction part and an up-down direction (Z).

  In the battery module, the heat diffusing unit has at least one hole that opens at least upward in a position overlapping the heat conducting unit in the vertical direction. Therefore, when the heat conducting part is disposed on the upper surface of the heat diffusing part, air, foreign matter, or the like between the heat diffusing part and the heat conducting part can be pushed out into the hole. Therefore, it is easy to suppress the entrapment of air or foreign matter between the heat diffusing part and the heat conducting part. This makes it easy to improve the heat dissipation of the battery.

As mentioned above, according to the said aspect, the battery module which is easy to improve the heat dissipation of a battery can be provided.
In addition, the code | symbol in the parenthesis described in the means to solve a claim and a subject shows the correspondence with the specific means as described in embodiment mentioned later, and limits the technical scope of this invention. It is not a thing.

Sectional drawing of the battery module in Embodiment 1. FIG. FIG. 3 is a top view of the battery module in the first embodiment. FIG. 3 is a cross-sectional view taken along line III-III in FIG. 2. FIG. 3 is a top view of a thermal diffusion unit in the first embodiment. The partially expanded view of FIG. Sectional drawing which shows the state which applied the heat conductive part to the lower surface of the battery in Embodiment 1. FIG. Sectional drawing which shows the state which the center part of the heat conduction part in Embodiment 1 contacted the center position of the thermal diffusion part. Sectional drawing for demonstrating a mode that the battery in which the heat conductive part was apply | coated in Embodiment 1 is pressed toward the thermal-diffusion part side. FIG. 3 is a cross-sectional view illustrating a state in which the thermal diffusion unit, the thermal diffusion unit, and a plurality of batteries are assembled in the first embodiment. FIG. 6 is a top view of a thermal diffusion unit in the second embodiment. FIG. 6 is a top view of a thermal diffusion unit in the third embodiment. The partially expanded side view of the battery module in Embodiment 4. FIG. FIG. 6 is a partially enlarged cross-sectional view of a battery module according to Embodiment 4. Sectional drawing of the battery module in Embodiment 5. FIG. The side view of the battery module in Embodiment 5. FIG. Sectional drawing of the battery module in Embodiment 6. FIG.

(Embodiment 1)
An embodiment of a battery module will be described with reference to FIGS.
As shown in FIG. 1, the battery module 1 of the present embodiment includes a heat exchanger 2, a heat diffusing unit 3, a heat conducting unit 4, and a battery 5. The heat diffusion unit 3 is in thermal contact with the heat exchanger 2. The heat conducting unit 4 is disposed on the upper surface 31 of the heat diffusing unit 3. The battery 5 is in thermal contact with the upper surface of the heat conducting unit 4. The thermal diffusion unit 3 has a higher thermal conductivity than the thermal conduction unit 4. The thermal diffusion unit 3 has at least one hole 32 that opens at least upward, at a position overlapping the thermal conduction unit 4 in the vertical direction Z.

The battery module 1 is used as a power source for the apparatus. For example, the battery module 1 can be used as a power source for driving a rotating electrical machine for an internal combustion engine.
Note that the direction in which the heat diffusing unit 3 and the heat conducting unit 4 are arranged is the vertical direction Z. Moreover, let the heat conduction part 4 side with respect to the heat-diffusion part 3 in the up-down direction Z be an upper side, and let the opposite side be a lower side.

  In the present embodiment, the battery 5 is a lithium ion secondary battery. The battery 5 is a so-called can-type battery whose exterior is made of a metal such as iron or aluminum. As shown in FIGS. 1 to 3, the battery 5 includes a battery main body 51 and a pair of terminals 52 protruding upward from the battery main body 51.

  As shown in FIGS. 1 and 2, the battery 5 has a flat plate shape having a thickness in one direction orthogonal to the vertical direction Z. In the present embodiment, the plurality of batteries 5 have substantially the same shape.

  The plurality of batteries 5 constitutes a battery structure 10 arranged in the arrangement direction X orthogonal to the vertical direction Z. Although not shown, the battery structure 10 is constrained in the alignment direction X. The plurality of batteries 5 are arranged side by side in the thickness direction of the battery 5 to constitute the battery structure 10. In the present embodiment, the lower surface 53 of the battery 5 has a rectangular shape having a short direction in the alignment direction X and a longitudinal direction in the vertical direction Y perpendicular to both the alignment direction X and the vertical direction Z. Yes. In the battery structure 10, an insulating material 11 is disposed between the adjacent batteries 5 to prevent the battery main bodies 51 from being in electrical contact. The plurality of batteries 5 are configured so that the positions of the terminals 52 of the batteries 5 are aligned with each other when the battery structure 10 is configured. That is, the plurality of batteries 5 are arranged so that the positions of the upper ends in the vertical direction Z coincide with each other. The plurality of batteries 5 are arranged on the upper surface of the heat conducting unit 4 arranged on the upper surface 31 of the heat diffusing unit 3.

  The heat conducting unit 4 is disposed between the lower surface 53 of each battery 5 and the upper surface 31 of the heat diffusing unit 3. The heat conducting unit 4 is in close contact with the upper surface 31 of the heat diffusing unit 3 and the lower surface 53 of each battery 5. Further, the heat conducting unit 4 is in thermal contact with the heat diffusing unit 3 and the plurality of batteries 5. The substantially entire lower surface of the heat conducting unit 4 is in surface contact with the substantially entire upper surface 31 of the heat diffusing unit 3. Further, the lower surface of the heat conducting unit 4 is in direct contact with the upper surface 31 of the heat diffusing unit 3. The heat conduction part 4 has heat conductivity. The heat conduction part 4 is preferably elastically deformable. Moreover, it is preferable that the heat conductive part 4 has electrical insulation. The heat conduction part 4 can be comprised, for example with silicone. When viewed from the vertical direction Z, a plurality of batteries 5 are arranged inside the outer peripheral contour of the heat conducting unit 4.

  As shown in FIGS. 1 and 3, the heat diffusing portion 3 is arranged on the lower surface of the heat conducting portion 4. The thermal diffusion unit 3 is made of aluminum, for example. The heat diffusing unit 3 is not limited to this, and other materials can be adopted as long as the thermal conductivity is higher than that of the heat conducting unit 4. The thermal diffusion part 3 is formed in a plate shape having a thickness in the vertical direction Z. When viewed from the vertical direction Z, a plurality of batteries 5 are arranged inside the outer peripheral contour of the thermal diffusion unit 3.

  As shown in FIG. 1, the heat diffusing unit 3 has a plurality of holes 32 at positions overlapping the heat conducting unit 4 in the vertical direction Z. As shown in FIG. 4, the hole 32 has a circular shape when viewed from the vertical direction Z. As shown in FIG. 1, the hole 32 is open toward both the upper side and the lower side in the thermal diffusion unit 3. In the present embodiment, the hole 32 is formed so as to penetrate the heat diffusing portion 3 in the vertical direction Z. However, the present invention is not limited to this, and the hole portion 32 may be formed so as to penetrate the heat diffusing portion 3 in a direction inclined in the vertical direction Z.

  In the present embodiment, as shown in FIGS. 1 and 4, at least one hole 32 is formed at a position overlapping the lower surface 53 of the battery 5 in the vertical direction Z. That is, the lower surface 53 of the battery 5 is disposed above the at least one hole 32 in the thermal diffusion unit 3. Hereinafter, a region overlapping the lower surface 53 of the battery 5 in the vertical direction Z in the heat diffusion unit 3 may be referred to as an overlapping region 33. In FIG. 4, the outline of the overlapping region 33 is indicated by a broken line. Of the thermal diffusion part 3, the part overlapping the battery 5 in the vertical direction Z is the total area of the hole part 32 when viewed from the vertical direction Z, and the area of the part other than the hole part 32 when viewed from the vertical direction Z Smaller than. When viewed from the up-down direction Z, the hole 32 is accommodated inside the contour of the lower surface 53 of the battery 5.

  As shown in FIG. 5, the center position of the lower surface 53 of the battery 5 in the short direction of the lower surface 53 of the battery 5 (that is, the arrangement direction X) is defined as a center position xc. In the arrangement direction X, the positions of both ends of the batteries 5 are defined as a first end position x1 and a second end position x2, respectively. Furthermore, in the arrangement direction X, the center position between the center position xc and the first end position x1 is defined as the first intermediate position x1c, and the center position between the center position xc and the second end position x2 is defined as the second position. It is defined as an intermediate position x2c. At this time, at least a part of the hole 32 is present at least between the first intermediate position x1c and the first end position x1 and between the second intermediate position x2c and the second end position x2. . For example, when the lower surface 53 of the battery 5 is circular, the short direction of the lower surface 53 of the battery 5 refers to at least one direction among the directions orthogonal to the vertical direction Z. The two holes 32 only have to exist between the first intermediate position x1c and the first end position x1 and between the second intermediate position x2c and the second end position x2. There may be a hole 32 in a region (for example, between the center position xc and the first intermediate position x1c, between the intermediate position xc and the second intermediate position x2c, etc.).

  As shown in FIG. 4, in the overlapping region 33, holes 32 are arranged at equal intervals in five places in the vertical direction Y.

  As shown in FIG. 1, the heat exchanger 2 is disposed on the lower surface of the heat diffusion unit 3. The heat exchanger 2 is not specifically limited, For example, what has a refrigerant flow path inside can be employ | adopted. Further, the heat exchanger 2 is not limited to the one disposed on the lower surface of the heat diffusion unit 3 as long as it is in thermal contact with the heat diffusion unit 3.

Next, an example of a method for assembling the plurality of batteries 5, the heat conduction unit 4, and the heat diffusion unit 3 will be described with reference to FIGS. 6 to 9.
First, as shown in FIG. 6, the heat conducting portion 4 is applied to each of the lower surfaces 53 of the plurality of batteries 5. At this time, in the heat conducting portion 4, the central portion 41 in the short side direction (that is, the arrangement direction X) of the lower surface 53 of the battery 5 swells downward. This is due to the surface tension of the heat conducting portion 4.

  Next, as shown in FIG. 7, the plurality of batteries 5 coated with the heat conducting unit 4 are brought close to the heat diffusing unit 3, and the lower end of the heat conducting unit 4 is brought into contact with the upper surface 31 of the heat diffusing unit 3. At this time, the central part 41 of the heat conducting part 4 in the arrangement direction X is swelled to the lowermost side, and the central part 41 of the heat conducting part 4 first comes into contact with the central position xc of the heat diffusing part 3.

  Next, as shown in FIG. 8, a plurality of batteries 5 are further pushed into the heat diffusing unit 3 side. As the plurality of batteries 5 are pushed in, the part of the surface of the heat conducting unit 4 that is away from the central part 41 sequentially contacts the heat diffusing unit 3. Accordingly, the heat conducting unit 4 pushes the air between the heat diffusing unit 3 toward the side opposite to the center position xc in the arrangement direction X. The extruded air is a hole formed between the first intermediate position x1c and the first end position x1 in the arrangement direction X and between the second intermediate position x2c and the second end position x2. Extruded to part 32. Then, as shown in FIG. 9, the plurality of batteries 5 are pushed into the heat diffusing section 3 until the heat conducting sections 4 applied to the lower surface 53 of the adjacent batteries 5 are connected and integrated. As a result, it is possible to obtain a state in which the upper surface of the integrated heat conducting unit 4 is in close contact with the lower surfaces 53 of the plurality of batteries 5 and the lower surface of the heat conducting unit 4 is in close contact with the upper surface 31 of the heat diffusing unit 3.

Next, the effect of this embodiment is demonstrated.
In the present embodiment, the heat diffusing unit 3 has at least one hole 32 that opens at least upward in a position overlapping the heat conducting unit 4 in the vertical direction Z. Therefore, when the heat conducting unit 4 is disposed on the upper surface 31 of the heat diffusing unit 3, air, foreign matter, or the like between the heat diffusing unit 3 and the heat conducting unit 4 can be pushed out into the hole 32. Therefore, it is easy to suppress the entrapment of air or foreign matter between the thermal diffusion unit 3 and the thermal conduction unit 4. Thereby, it is easy to improve the heat dissipation of the battery 5.

  Further, at least one hole 32 is formed at a position overlapping the lower surface 53 of the battery 5 in the vertical direction Z. Therefore, it is possible to prevent air or foreign matter from being caught between the heat conducting unit 4 and the heat diffusing unit 3 just below the lower surface 53 of the battery 5. Thereby, it is easy to reduce the thermal resistance in the heat transfer path from the battery 5 to the heat exchanger 2.

  Further, in the heat diffusion part 3, the part overlapping the battery 5 in the vertical direction Z is a part other than the hole part 32 when the total area of the hole part 32 when viewed from the vertical direction Z is viewed from the vertical direction Z. Is smaller than the area. Therefore, it is easy to secure the volume of the overlapping region 33 of the thermal diffusion unit 3. Thereby, it is easy to reduce the thermal resistance in the heat transfer path from the battery 5 to the heat exchanger 2.

  In addition, at least a part of the hole 32 is present at least between the first intermediate position x1c and the first end position x1 and between the second intermediate position x2c and the second end position x2. Therefore, as described above, when the battery module 1 is assembled, air, foreign matter, and the like pushed out by the heat conducting unit 4 and the heat diffusing unit 3 are easily guided to the hole 32. Thereby, it is easier to prevent air, foreign matter, and the like from being caught between the heat diffusing unit 3 and the heat conducting unit 4.

  Further, the hole 32 has a circular shape when viewed in the vertical direction Z. Therefore, it is easy to form the hole 32 in the thermal diffusion part 3. Therefore, it can suppress that the productivity of the battery module 1 falls.

  Moreover, the hole part 32 is opened toward both the upper side and the lower side in the thermal diffusion part 3. Therefore, air or foreign matter pushed out by the heat conducting unit 4 and the heat diffusing unit 3 can pass through the hole 32 to the lower side of the heat conducting unit 4. Therefore, it is easier to prevent air, foreign matter, etc. from being trapped between the heat diffusing unit 3 and the heat conducting unit 4.

  As described above, according to the present embodiment, it is possible to provide a battery module that can easily improve the heat dissipation of the battery.

(Embodiment 2)
As shown in FIG. 10, the present embodiment is an embodiment in which the shape of the hole 32 is modified with respect to the first embodiment. Specifically, when viewed from the vertical direction Z, the hole portion 32 has an elliptical shape that is long in the vertical direction Y. Two holes 32 are arranged in the vertical direction Y in the overlapping region 33. They are formed on both sides of the overlapping region 33, respectively.

Others are the same as in the first embodiment.
Of the reference numerals used in the second and subsequent embodiments, the same reference numerals as those used in the above-described embodiments represent the same components as those in the above-described embodiments unless otherwise indicated.

  This embodiment also has the same effects as those of the first embodiment.

(Embodiment 3)
As shown in FIG. 11, the present embodiment is also an embodiment in which the shape of the hole portion 32 is modified with respect to the first embodiment. Specifically, the hole 32 has a long slit shape in the arrangement direction X. The holes 32 are formed long in the alignment direction X so as to be positioned below all the batteries 5. In the arrangement direction X, the holes 32 are continuously formed from the vicinity of one end of the battery structure 10 in the arrangement direction X to the vicinity of the other end. Among the plurality of batteries 5, the overlapping region 33 on the lower side of the batteries 5 other than the batteries 5 at both ends has a hole 32 formed over the entire alignment direction X. It should be noted that the holes 32 may be formed over the entire alignment direction X in the lower overlapping region 33 of all the batteries 5. Five holes 32 are formed in the thermal diffusion part 3. The five holes 32 are formed at equal intervals in the vertical direction Y.
Others are the same as in the first embodiment.

In the present embodiment, at least a part of the hole 32 is positioned between the first intermediate position x1c and the first end position x1 and between the second intermediate position x2c and the second end position x2. Easy to make. That is, by forming the hole 32 into a slit shape that is long in the vertical direction Y, the first intermediate position x1c and the first position can be obtained without precisely designing the positional relationship in the alignment direction X between the hole 32 and the battery 5. At least a portion of the hole 32 can be positioned between the one end position x1 and between the second intermediate position x2c and the second end position x2. The first intermediate position x1c, the first end position x1, the second intermediate position x2c, the second end position x2, and the like are the same as those shown in Embodiment 1, FIG.
In addition, the same effects as those of the first embodiment are obtained.

(Embodiment 4)
As shown in FIGS. 12 and 13, the present embodiment is an embodiment in which the exterior 50 of the battery 5 has a laminate structure. As shown in FIG. 13, the outer package 50 of the battery 5 is laminated in the order of the heat sealing layer 501, the metal layer 502, and the protective layer 503 from the inner side to the outer side of the outer package 50. The heat-sealing layer 501 is a layer that is heat-sealed to the sealing resin filled inside the exterior 50 of the battery 5. The metal layer 502 is a layer made of aluminum. The protective layer 503 is a layer formed on the outer surface of the exterior 50 and is a layer that protects the exterior 50.

  As shown in FIGS. 1 and 2, a heat transfer plate 12 is interposed between the batteries 5 adjacent to each other in the arrangement direction X. The battery 5 is in thermal contact with the upper surface of the heat conducting unit 4 via the heat transfer plate 12. The heat transfer plate 12 has a shape obtained by bending a long plate into an L shape in the thickness direction. The heat transfer plate 12 includes a first part 121 having a thickness in the arrangement direction X and a second part 122 having a thickness in the vertical direction Z. Between the batteries 5 adjacent to each other in the arrangement direction X, the first portion 121 of the heat transfer plate 12 is disposed. As for the 1st site | part 121 distribute | arranged between the batteries 5 adjacent in the row direction X, one main surface is in surface contact with the main surface of one battery 5 of the said adjacent battery 5, and the other main surface is the said. The adjacent battery 5 is in surface contact with the main surface of the other battery 5. The lower surface of the second portion 122 is in surface contact with the upper surface of the heat conducting unit 4.

The hole 32 of the heat conducting unit 4 is formed below the lower surface 53 of the battery 5 and below the lower surface of the second portion 122.
Others are the same as in the first embodiment.

In the present embodiment, even when the exterior 50 of the battery 5 has a laminated structure, the heat of the battery 5 is easily transmitted to the heat exchanger 2 via the heat transfer plate 12.
In addition, the same effects as those of the first embodiment are obtained.

(Embodiment 5)
As shown in FIGS. 14 and 15, the present embodiment is an embodiment in which the arrangement posture of the battery 5 is changed with respect to the first embodiment. In the present embodiment as well, as in the first embodiment, the direction in which the thermal diffusion unit 3 and the thermal conduction unit 4 are arranged is referred to as the vertical direction Z, and the thermal conduction unit 4 side with respect to the thermal diffusion unit 3 in the vertical direction Z The opposite side is called the lower side.

  In the present embodiment, the battery 5 has a terminal 52 protruding in one of a vertical direction Y orthogonal to the vertical direction Z and the arrangement direction X. The plurality of batteries 5 all have terminals 52 protruding on the same side in the vertical direction Y. In the present embodiment, the lower surface 53 of the battery 5 is a surface adjacent to the surface from which the terminal 52 of the battery body 51 protrudes. Also in this embodiment, the lower surface 53 of the battery 5 is in thermal contact with the upper surface of the heat conducting unit 4.

The heat diffusion part 3 has holes 32 arranged at equal intervals in four places in the longitudinal direction Y.
Others are the same as in the first embodiment.

  This embodiment also has the same effects as those of the first embodiment.

(Embodiment 6)
In the present embodiment, as shown in FIG. 16, the lower side of the hole 32 in the thermal diffusion unit 3 is closed. That is, the hole 32 of the present embodiment is a bottomed hole that is open on the upper side and closed on the lower side.
Others are the same as in the first embodiment.

In the present embodiment, it is easy to ensure the heat capacity of the thermal diffusion unit 3.
In addition, the same effects as those of the first embodiment are obtained.

  The present invention is not limited to the embodiments described above, and can be applied to various embodiments without departing from the scope of the invention. For example, in each of the embodiments described above, the battery 5 is a lithium ion secondary battery, but is not limited thereto, and various batteries can be employed. For example, the battery can be a nickel metal hydride battery. The battery may be a battery pack in which a plurality of single cells are accommodated in a pack case.

DESCRIPTION OF SYMBOLS 1 Battery module 2 Heat exchanger 3 Thermal diffusion part 31 Upper surface of thermal diffusion part 32 Hole part 4 Thermal conduction part 5 Battery Z Vertical direction

Claims (8)

A heat exchanger (2);
A thermal diffusion section (3) in thermal contact with the heat exchanger;
A heat conducting part (4) disposed on an upper surface (31) of the heat diffusing part;
A battery (5) in thermal contact with the upper surface of the heat conducting part,
The thermal diffusion part has higher thermal conductivity than the thermal conduction part,
The battery module (1), wherein the heat diffusing part has at least one hole (32) opening at least upward in a position overlapping with the heat conducting part in a vertical direction (Z).   The battery module according to claim 1, wherein at least one of the hole portions is formed at a position overlapping with a lower surface of the battery in a vertical direction.   Of the thermal diffusion part, the part overlapping the battery in the vertical direction has a smaller total area of the hole part when viewed from the vertical direction than the area of the part other than the hole part when viewed from the vertical direction. The battery module according to claim 2.   In the short direction of the lower surface of the battery, the center position of the lower surface of the battery is defined as a center position (xc), and the positions of both ends of the battery are the first end position (x1) and the second end, respectively. A central position between the central position and the first end position is defined as a first intermediate position (x1c), and a central position between the central position and the second end position. When the position is defined as the second intermediate position (x2c), at least between the first intermediate position and the first end position, and between the second intermediate position and the second end position. The battery module according to claim 2, wherein at least a part of the hole is present.   The battery module according to any one of claims 1 to 4, wherein the hole portion has a circular shape when viewed from the vertical direction.   The said hole part is a battery module as described in any one of Claims 1-4 which is exhibiting the slit shape long in one direction orthogonal to an up-down direction.   The said hole part is a battery module as described in any one of Claims 1-6 opened toward both the upper side and lower side in the said thermal-diffusion part.   The battery module according to any one of claims 1 to 6, wherein a lower side of the hole portion in the heat diffusion portion is closed.

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