WO2014050109A1

WO2014050109A1 - Power source system

Info

Publication number: WO2014050109A1
Application number: PCT/JP2013/005714
Authority: WO
Inventors: 大樹内山; 康広浅井; 洋彰藤原
Original assignee: 三洋電機株式会社
Priority date: 2012-09-27
Filing date: 2013-09-26
Publication date: 2014-04-03
Also published as: JP2015232922A

Abstract

Provided is a power source system wherein effects of cooling a battery module are improved with a simple structure. A power source system (1) is provided with: a battery module (6) that includes a plurality of batteries (30); a cooling apparatus (100) that cools the battery module (6); and at least one fixing member (10) that fixes the battery module (6) to the cooling apparatus (100). The battery module (6) is formed in a rectangular parallelepiped shape, and includes locking sections (18) that are formed at the both ends of the battery module (6) in the lateral direction of the battery module in a planar view of a surface fixed to the cooling apparatus (100). The cooling apparatus (100) is fixed to the battery module (6), has a cooling surface having different longitudinal and lateral lengths, and is disposed such that the longitudinal direction of the cooling surface is substantially equal to the longitudinal direction of the battery module (6). At least the one fixing member (10) includes sections to be locked (96), which are formed at both the ends of the fixing member, and which are locked to the locking sections (18), and in a state where the locking sections (18) are locking the section to be locked (96), the cooling apparatus (100) is pressed to the battery module (6).

Description

Power system

The present invention relates to a power supply system including a cooling device.

Generally, in a power supply system having a battery module configured by connecting a plurality of batteries, the battery module generates heat due to charging / discharging of the power supply system. Therefore, a cooling plate (hereinafter also referred to as a cooling device) may be provided in the power supply system. For example, Patent Document 1 discloses a technique for stacking unit battery cells and a cooling plate.

JP-A-2005-116323

However, in the conventional power supply system, the battery module and the cooling plate are fixed with a bolt or the like. Therefore, both were not fully fixed and adhesiveness was inadequate. For example, in the cooling structure of Patent Document 1, fixing both has not been sufficiently studied. Therefore, there was a problem that the cooling effect by the cooling plate could not be sufficiently exhibited. In addition, there was a difference in the thermal conductivity from the battery to the cooling plate depending on the location. Therefore, there has been a problem that the cooling effect varies depending on the location in the battery module.

The present invention has been made in view of these problems, and an object thereof is to provide a technique for enhancing the cooling effect of the battery module with a simple structure.

One aspect of the present invention is a power supply system. The power supply system includes a battery module including a plurality of batteries, a cooling device that cools the battery module, and at least one fixing member that fixes the battery module to the cooling device. The battery module is formed in a rectangular parallelepiped shape, and includes locking portions formed at both ends in the short direction of the battery module when the surface fixed to the cooling device is viewed in plan. The cooling device is fixed to the battery module, has a cooling surface with different vertical and horizontal lengths, and is arranged so that the longitudinal direction of the cooling surface is substantially the same as the longitudinal direction of the battery module. At least one fixing member is formed at both ends of the fixing member and includes a locked portion that is locked with the locking portion. When the locking portion is locked to the locked portion, the cooling device faces the battery module. It is characterized by energizing.

According to this power supply system, a sufficient urging force can be applied to the battery module 6 from the cooling device 100 by locking the battery module in the short direction using the fixing member. Thereby, with a simple structure, the thermal conductivity from a battery module to a cooling device can be improved, and the cooling effect by a cooling device can be improved. Further, the locking between the locking portion and the locked portion can be strengthened, and the installation state of the power supply system can be further stabilized.

According to the present invention, the cooling effect of the battery module can be enhanced with a simple structure.

It is a perspective view which shows the state before the assembly of the power supply system which concerns on embodiment. It is sectional drawing which shows schematic structure of a battery. 3A and 3B are a perspective view and a front view, respectively, of a fixing member used in the power supply system according to the embodiment. 4A, 4B, and 4C are a perspective view, a front view, and a bottom view, respectively, of the power supply system according to the embodiment. FIG. 5A and FIG. 5B are a front view of a fixing member and a front view of a power supply system according to modifications, respectively.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In all the drawings, the same reference numerals are given to the same components, and the description will be omitted as appropriate.

FIG. 1A is a perspective view showing a state before assembly of the power supply system 1 according to the embodiment. FIG. 2 is a cross-sectional view showing a schematic structure of the battery 30. FIGS. 3A and 3B are a perspective view and a front view of the fixing member 10 used in the power supply system 1 according to the embodiment, respectively. 4A, 4B, and 4C are a perspective view, a front view, and a bottom view, respectively, of the power supply system 1 according to the embodiment. Hereinafter, a power supply system 1 according to an embodiment will be described with reference to FIGS.

As shown in FIG. 1, the power supply system 1 includes a battery module 6 including a plurality of batteries 30, a cooling device 100 that cools the battery module 6, and at least one fixing member 10 that fixes the battery module 6 to the cooling device 100. With. Hereinafter, these configurations will be described in order.

The battery module 6 is formed in a substantially rectangular parallelepiped shape as a whole. Specifically, the battery module 6 has a long side and a short side substantially orthogonal to the long side when the surface on which the cooling device 100 described later is urged in the installed state of the power supply system 1 is viewed in plan view, A plurality of batteries 30 are stacked. The battery module 6 includes a separator 70, an end plate 80 and a side plate 90 in addition to the plurality of batteries 30. In the present embodiment, a total of 12 batteries 30 are electrically connected in series to form an assembled battery. Note that the number of the batteries 30 is not particularly limited. In the present embodiment, all the twelve batteries 30 are electrically connected in series, but some of them may be connected in parallel. A separator 70 made of an insulating resin such as plastic is provided between the adjacent batteries 30. By the separator 70, the insulation between the adjacent batteries 30 is enhanced.

The battery module 6 includes a plurality of submodules 4 each including a plurality of batteries 30. The submodule 4 is fixed to one surface (cooling surface 110) of the cooling device 100, and a plurality of submodules 4 are arranged in the longitudinal direction of the cooling device 100. The battery 30 included in the submodule 4 is a flat rectangular parallelepiped battery, and a plurality of batteries 30 are stacked in the submodule 4 so that the main surfaces thereof are opposed and substantially parallel. In the installed state of the power supply system 1, the submodule 4 is arranged so that the longitudinal direction of the plurality of batteries 30 included in the submodule 4 is substantially the same as the longitudinal direction of the battery module 6 (that is, the main surface is short of the battery module 6). Arranged so that it faces the hand).

In the three submodules 4 of the present embodiment, four batteries 30 are stacked in one direction (here, a direction perpendicular to the longitudinal direction of the battery module 6). The sub-module 4 has two side surfaces facing each other by a pair of end plates 80 arranged at both ends in the stacking direction, which are left by two U-shaped metal side plates 90 fixed to the pair of end plates 80. Each side is covered. The pair of end plates 80 includes a locking portion 96 and is disposed along the longitudinal direction of the battery module 6, that is, so that the surface of each end plate 80 is substantially perpendicular to the short direction of the cooling device 100. . The sub-module 4 is formed by engaging the end plate 80 and the side plate 90 with screws 94. Each of the three submodules 4 is covered with an end plate 80 and a side plate 90 on the side surfaces. Therefore, in the whole battery module 6 shown in FIGS. 1 and 4A, six end plates 80 and six side plates 90 are used.

The submodule 4 is arranged so that the end plate 80 forms a side surface in the long side direction of the battery module 6 (FIG. 4A). When the number of batteries 30 used in the submodule 4 is increased, in the submodule 4, the side plate 90 may be longer in the horizontal direction when installed than the end plate 80. In this case, the end plate 80 forms the long side of the battery module 6 by increasing the number of submodules 4 used in the battery module 6 and arranging the end plates 80 in a straight line.

The battery module 6 has locking portions 96 provided at both ends in the short direction, that is, at end plate extending portions 92 formed in the vicinity of the surface in contact with the cooling device 100 in the installed state (FIGS. 1 and 2). (4) End plate extending portion 92 and locking portion 96 on the back side of the drawing are not shown). The locking part 96 is locked to a locked part 18 provided on the fixing member 10 described later. In the present embodiment, the locking portion 96 is a hole formed by cutting out the end plate extending portion 92. When the plurality of submodules 4 are arranged along the longitudinal direction of the cooling device 100, the locking portion 96 is preferably provided in each submodule 4.

On the upper surface of the casing of the battery 30, a negative terminal 50 is provided near one end in the longitudinal direction, and a positive terminal 60 is provided near the other end. Hereinafter, the negative electrode terminal 50 and the positive electrode terminal 60 are collectively referred to as external terminals as appropriate. In the submodule 4, the negative electrode terminal 50 and the positive electrode terminal 60 of the adjacent battery 30 are arranged so as to be opposite to each other. Twelve batteries 30 are connected in series by electrically connecting one positive terminal 60 and the other negative terminal 50 of two adjacent batteries 30 by a bus bar (not shown). The positive terminal 60 ′ serving as one terminal of the series connection of the batteries 30 and the negative terminal 50 ′ serving as the other terminal can be connected to an external load (both not shown) via wiring routed outside the housing. It has become.

Next, the structure of the battery 30 will be described. The battery 30 is a flat rectangular parallelepiped battery. In the battery 30, an electrode body 32 in which positive and negative electrodes are wound in a spiral shape is housed in a flat rectangular parallelepiped outer can (housing) 31 so as to be transverse to the can axis direction of the outer can 31. The opening of the outer can 31 is sealed by a sealing plate 33 that constitutes a part of the housing. The sealing plate 33 is provided with a negative electrode terminal 50 and a positive electrode terminal 60. The sealing plate 33 is formed with a gas discharge valve (not shown).

The negative electrode terminal 50 has a base 50a, a first flange 50b, and a second flange 50c. The base 50a has a substantially cylindrical shape, and a plate-like first flange 50b is formed at one end of one end disposed on the outside of the housing, and a slope is formed at the other end of the one end. The second flanges 50c are connected to each other. A bolt portion 52 is integrally formed on the slope of the second flange portion 50c. The base portion 50 a of the negative electrode terminal 50 is fitted into the negative electrode opening 33 a of the sealing plate 33 with the gasket 34 in contact with the side surface. The gasket 34 is also in contact with the surfaces of the first flange portion 50b and the second flange portion 50c facing the sealing plate 33. Further, the base portion 50 a is connected to the negative electrode tab member 54 on the battery inner side of the sealing plate 33.

A recess 51 is formed at the tip of the base 50a located inside the battery so that a side wall is formed along the negative electrode opening 33a. By caulking the edge portion of the recess 51 so as to expand, the negative electrode terminal 50 is fixed to the negative electrode tab member 54 and the inside of the battery 30 is sealed.

An insulating plate 35 is provided between the negative electrode tab member 54 and the battery inner surface of the sealing plate 33. The insulating plate 35 and the gasket 34 are in contact with each other at the negative electrode opening 33a. Thereby, the negative electrode tab member 54 and the negative electrode terminal 50 are insulated from the sealing plate 33. The negative electrode tab member 54 is connected to the negative electrode current collector plate group 32 a protruding from one end surface of the electrode body 32. The negative electrode current collector plate group 32 a is a bundle of a plurality of negative electrode current collector plates protruding from one end face of the electrode body 32.

The positive electrode terminal 60 has a base 60a, a first collar 60b, and a second collar 60c. The base 60a has a substantially cylindrical shape, and a plate-like first flange 60b is formed at one end of one end disposed on the outside of the housing, and a slope is formed at the other end of the one end. The second flange portions 60c are connected to each other. A bolt portion 62 is integrally formed on the slope of the second flange portion 60c. The base portion 60 a of the positive electrode terminal 60 is fitted into the positive electrode opening 33 b of the sealing plate 33 with the gasket 34 in contact with the side surface. The gasket 34 is also in contact with the surfaces of the first flange portion 60b and the second flange portion 60c facing the sealing plate 33. The base portion 60 a is connected to the positive electrode tab member 64 on the battery inner side of the sealing plate 33.

A recess 61 is formed at the tip of the base 60a located inside the battery so that a side wall is formed along the positive electrode opening 33b. By caulking the edge portion of the recess 61 so as to expand, the positive electrode terminal 60 is fixed to the positive electrode tab member 64 and the inside of the battery 30 is sealed.

An insulating plate 35 is provided between the positive electrode tab member 64 and the battery inner surface of the sealing plate 33. The insulating plate 35 and the gasket 34 are in contact with each other at the positive electrode opening 33b. Thereby, the positive electrode tab member 64 and the positive electrode terminal 60 are insulated from the sealing plate 33. The positive electrode tab member 64 is connected to the positive electrode current collector plate group 32 b protruding from the other end face of the electrode body 32. The positive electrode current collector plate group 32 b is a bundle of a plurality of positive electrode current collector plates protruding from the other end face of the electrode body 32.

The bus bar (not shown) is a belt-like member made of a conductive material such as metal and has through holes at both ends. By inserting the bolt portion 52 of the negative electrode terminal 50 into one through hole of the bus bar and fixing with a nut (not shown), the bus bar and the negative electrode terminal 50 are physically and electrically connected. Moreover, the bus bar and the positive electrode terminal 60 are physically and electrically connected by inserting the bolt portion 62 of the positive electrode terminal 60 into the other through hole of the bus bar and fixing it with a nut (not shown).

The cooling device 100 has a cooling surface 110 in which a main body 102 is formed in a substantially rectangular parallelepiped shape and is fixed to the battery module 6 with different vertical and horizontal lengths. Therefore, when the cooling surface 110 is viewed in a plan view with the power supply system 1 installed, it has a long side and a short side substantially orthogonal to the long side (FIGS. 1 and 4). The cooling device 100 is fixed to one surface of the battery module 6 so that the longitudinal direction of the cooling surface 110 is substantially the same as the longitudinal direction of the battery module 6. A heat conductive sheet may be provided between the battery module 6 and the cooling device 100. As described above, the fixed state in the present embodiment includes a state in which the battery module 6 and the cooling device 100 are not in physical contact but are thermally connected.

A U-shaped tube 108 is formed inside the main body 102 (FIG. 3C). The cooling water flowing through the inside removes the heat generated in the battery module 6, thereby cooling the battery module 6. Water is supplied from a supply port 104 that is an inlet of the U-shaped tube 108, and is discharged from a discharge port 106 that is an outlet of the U-shaped tube 108. Water circulation is performed by a pump (not shown). Note that the cooling device 100 may be a simple metal plate in which cooling water does not flow. In this case, it is preferable to form the cooling device 100 using a material such as aluminum having high thermal conductivity.

The fixing member 10 is disposed in contact with the surface 112 opposite to the cooling surface 110 of the cooling device 100, and fixes the cooling device 100 to the battery module 6. As shown in FIG. 3, the fixing member 10 includes a plate-like base portion 12 and a pair of side portions 14 formed integrally with the base portion 12. The pair of side portions 14 is erected substantially perpendicular to the base portion 12 so as to be substantially parallel to each other. The base 12 is curved so as to be convex toward the cooling device 100 (FIG. 3B).

The side portion 14 is provided with a locked portion 18 to be locked with the locking portion 96 and a hole 22 for facilitating attachment / detachment of the fixing member 10 to / from the power supply system 1. In order to be locked with the locking portion 96 formed in the hole shape of the battery module 6, the locked portion 18 is a convex portion that faces the locking portion 96 in the installed state of the power supply system 1 here. Is formed. In addition, the base 12 is formed with a slit 20 for improving the deformability at the time of fixing. Further, the fixing member 10 is formed with a slit 24 extending from the base portion 12 to the side portion 14. Therefore, the fixing member 10 is formed in a net shape by the

slits

20 and 24. Further, the side portion 14 is formed with a side portion extending portion 16 and a hole 26 provided in the side portion extending portion 16. The fixing member 10 is screwed to the battery module 6 through the hole 26 as necessary.

The fixing member 10 is made of high-tensile steel (high-tensile steel) having elasticity, heat resistance, durability, and water resistance. The thickness of the high tension steel can be set to 0.8 mm, for example. However, any material having such properties can be suitably used as the material of the fixing member 10. For example, a general steel plate or a stainless spring material can be used.

Next, with reference to FIG. 1 and FIG. 4, the installation of the power supply system 1, that is, the fixing of the battery module 6 and the cooling device 100 using the fixing member 10 will be described. The battery module 6 has end plate extending portions 92 at both ends of the module. Further, the distance between the end plate extending portions 92 in the short direction of the battery module 6 is substantially the same as the width of the cooling device 100 in the short direction. Thereby, when the battery module 6 is arrange | positioned with respect to the cooling surface 110 of the cooling device 100, the relative position of the transversal direction of the battery module 6 and the cooling device 100 is fixed.

Further, in the installed state of the power supply system 1, the fixing member 10 is disposed in contact with the surface 112 of the cooling device 100 in a direction in which the side portion 14 is substantially parallel to the long side of the power supply system 1. Therefore, the locked portion 18 provided on the side portion 14 is in the vicinity of both ends in the short direction of the battery module 6 when viewed in plan in the installed state of the power supply system 1, and the locking portion 96. It is arranged at a position where it can be locked. As a result, the locked portion 18 is locked with the locking portion 96. Due to the locking of the locked portion 18 and the locking portion 96, a stress perpendicular to the surface 112 is generated from the fixing member 10 toward the cooling device 100 in a state where the fixing member 10 and the battery module 6 are fixed. . Thereby, the fixing member 10 urges the cooling device 100 toward the battery module 6. In addition, the fixing member 10 has a base 12 that is curved so as to protrude toward the cooling device 100. Therefore, the stress that the fixing member 10 applies to the cooling device 100 does not decrease even near the center of the cooling device 100.

1 and 4, the power supply system 1 is vertically installed, that is, the installation state in which the surface of the end plate 80 faces the horizontal direction, but the installation state is not limited to this. For example, the power supply system 1 may be installed sideways, that is, in a state where the end plate 80 faces in the vertical direction. Even in this case, the fixing member 10 urges the cooling device 100 toward the battery module 6.

As shown in FIG. 1, when the battery module 6 is configured by arranging the plurality of submodules 4 along the longitudinal direction of the cooling device 100, the fixing member 10 extends along the longitudinal direction of the battery module 6. Preferably, a plurality of submodules 4 are provided at predetermined intervals corresponding to the locking portions 96 of each submodule 4. Thus, the plurality of submodules 4 are preferably fixed to the cooling device 100 via the plurality of fixing members 10. In this case, it is particularly preferable that one fixing member 10 is provided for one submodule 4. However, a plurality of fixing members 10 may be provided for one submodule 4, or a plurality of submodules may be provided. One fixing member 10 may be provided for four.

According to the power supply system 1 described above, a sufficient urging force can be applied to the battery module 6 from the cooling device 100 by locking the battery module 6 in the short direction using the fixing member 10. it can. Thereby, with a simple structure, the thermal conductivity from the battery module 6 to the cooling device 100 can be enhanced, and the cooling effect by the cooling device 100 can be enhanced. Further, the locked state between the locked portion 18 and the locking portion 96 can be strengthened, and the installation state of the power supply system 1 can be further stabilized.

Further, by providing the fixing member 10 for each of the plurality of submodules 4, the battery module 6 and the cooling device 100 can be reliably fixed. In addition, even when a plurality of submodules 4 are provided, the urging force can be applied to the battery module 6 from the cooling device 100 while suppressing variation depending on the location.

Further, by providing the locking portion 96 on the end plate 80, the locking portion 96 is formed on the strong end plate 80, so that the battery module 6 can be fixed securely.

Further, by bending the base portion 12 in a mountain shape toward the direction in contact with the cooling device 100, a sufficient force can be applied also to the vicinity of the central portion in the short direction of the power supply system 1 where it is difficult to apply force. Thereby, the pressure distribution with respect to the cooling device 100 of the battery module 6 can be leveled, and the cooling device 100 can be urged | biased with respect to the battery module 6, suppressing the dispersion | variation by a place. As a result, the temperature deviation can be reduced throughout the battery module 6.

Further, by forming the

slits

20 and 24 in the fixing member 10 to enhance the deformability of the fixing member 10 in the installed state, even when the battery module 6 or the cooling device 100 is deformed due to heat generation, the fixing member 10 Thus, the biased state of both can be maintained.

Moreover, by providing a heat conductive sheet between the battery module 6 and the cooling device 100, the heat conduction efficiency from the battery module 6 to the cooling device 100 can be increased, and the battery module 6 can be cooled more efficiently. .

(Modification)
FIG. 5A and FIG. 5B are a front view of a fixing member 10 according to a modification and a front view of the power supply system 1, respectively. In the present modification, as shown in FIG. 5A, when the fixing member 10 is viewed in plan view from the surface in contact with the cooling device 100 in the installed state, the base portion 12 extends in the short direction of the battery module 6. It further has the extension part 28 formed by extending. This point is different from the fixing member 10 shown in FIG.

The base portion 12 and the extension portion 28 are integrally bent in a mountain shape (bow shape) in a direction in contact with the cooling device 100. In this case, the height of the mountain-shaped portion is higher than that in the case where the extending portion 28 is not provided. Therefore, when the cooling device 100 is fixed to the battery module 6 using the fixing member 10 of this modification, as shown in FIG. 5B, the fixing member 10 does not have the extending portion 28. The fixing member 10 is deformed more greatly. As a result, the opposing side portions 14 are more greatly deformed toward each other, so that the side portions 14 press the end plate extension portion 92 with a stronger force. The extending portion 28 is preferably the same member as the base portion 12.

According to this modification, the urging force of the cooling device 100 with respect to the battery module 6 and the fixation between the battery module 6 and the cooling device 100 can be further strengthened with a simple structure. In addition, since the extending portion 28 extends in the short direction of the power supply system 1, the stability at the time of installation of the power supply system 1 can be improved, and the overturn and the movement can be prevented.

1 power system, 4 sub-module, 6 battery module, 10 fixing member, 12 base, 14 side, 18 locked part, 28 extending part, 30 battery, 70 separator, 80 end plate, 96 locking part, 100 Cooling system

Claims

A battery module including a plurality of batteries, a cooling device for cooling the battery module, and at least one fixing member for fixing the battery module to the cooling device,
The battery module is
While being formed in a rectangular parallelepiped shape,
When the surface fixed to the cooling device is viewed in plan, including a locking portion formed at both ends in the short direction of the battery module,
The cooling device is
The battery module is fixed and has a cooling surface with different vertical and horizontal lengths,
The cooling surface is arranged so that the longitudinal direction thereof is substantially the same as the longitudinal direction of the battery module,
The at least one fixing member is
Formed at both ends thereof, including a locked portion to be locked with the locking portion,
In the state which the said latching | locking part latched to the said to-be-latched part, the said cooling device is urged | biased toward a battery module, The power supply system characterized by the above-mentioned.
A plurality of the fixing members;
The battery module includes a plurality of submodules,
The locking portion is formed on each of the plurality of submodules,
The power supply system according to claim 1, wherein the plurality of submodules are fixed to the cooling device via the plurality of fixing members.
The power supply system according to claim 2, wherein the plurality of submodules are arranged along a longitudinal direction of the cooling device.
The plurality of batteries include a plurality of rectangular batteries having a flat rectangular parallelepiped shape,
The plurality of sub-modules include the plurality of prismatic batteries stacked in one direction, and a pair of end plates disposed at both ends in the stacking direction,
4. The power source according to claim 3, wherein the pair of end plates includes the locking portion and is disposed so that a surface of each end plate is substantially perpendicular to a short direction of the cooling device. system.
The fixing member includes a plate-like base portion and a pair of side portions formed integrally with the base portion,
5. The pair of side portions is erected substantially perpendicular to the base portion so as to be substantially parallel to each other, and the locked portion is provided. The power supply system according to any one of the above.
The power supply system according to claim 5, wherein the base is curved so as to be convex toward the cooling device.
The power supply system according to claim 5 or 6, wherein the fixing member further includes an extending portion formed by extending the base portion in a short direction of the battery module.
The power supply system according to any one of claims 5 to 7, wherein the fixing member has a slit extending from the base portion to the side portion.