Power storage device module

Abstract

To provide a power storage device module which reduces heat conduction from a power storage device to an intervening member and can suppress propagation of heat to a power storage device adjacent to the module through the intervening member.SOLUTION: A power storage device module 500 includes: a plurality of power storage devices 1 arranged; and an intervening member 520 intervening between the power storage devices 1. Each power storage device 1 includes an electrode body 40 and a metal case 10 for storing the electrode body 40. The outer surface 11 of the case 10 includes contact parts 21 and 22 in contact with the intervening member 520. The contact parts 21, 22 have a large number of protruding parts 11t and have top part contact parts 23, 24 formed by reducing contact areas Sta and Stb in contact with the intervening member 520 in such a manner that the top parts 11tp of the protruding parts 11t are in contact with the intervening member 520.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present invention relates to a power storage device module in which a plurality of power storage devices are arranged in series via an intervening member.

Background Art

[0002] Conventionally, a battery module in which a plurality of batteries are arranged in series via an intervening member made of resin or the like is known. As a related prior art, for example, Patent Document 1 can be cited (see FIG. 1, Claim 1, etc. of Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In such a battery module, when a certain battery generates heat, the heat of the heat-generating battery is transmitted to the adjacent battery via the intervening member, so that the temperature of the adjacent battery also rises.

[0005] The present invention has been made in view of such a situation, and provides a power storage device module capable of reducing the heat conduction from the case of the power storage device to the intervening member and suppressing the transmission of heat to the adjacent power storage devices via the intervening member.

Means for Solving the Problems

[0006] (1) One aspect of the present invention for solving the above problems includes a plurality of energy storage devices arranged in a row and an intervening member interposed between adjacent energy storage devices. Each of the energy storage devices includes an electrode body and a metal case that houses the electrode body. The case has an outer surface of the case that is exposed to the outside, and the outer surface of the case is an energy storage device module including a contact portion that contacts the intervening member. The contact portion of the outer surface of the case includes a top contact portion having a large number of convex portions, and the tops of these convex portions abut against the intervening member to reduce the contact area with the intervening member.

[0007] In the above-described energy storage device module, the contact portion of the outer surface of the case of the energy storage device includes a top contact portion (the contact area when the convex portion is not provided on the top contact portion and is flat, that is, the contact area with the intervening member is reduced compared to the planar area of the top contact portion) in which the contact area with the intervening member is reduced by a large number of convex portions, and the contact portion of the energy storage device and the intervening member are in contact with each other in a small area. For this reason, compared with the case where the contact portion of the energy storage device does not have the above-described top contact portion, the heat conduction from the contact portion of the energy storage device to the intervening member can be lowered. Thereby, when a certain energy storage device generates heat, it is possible to suppress the heat from being transmitted to the adjacent energy storage device through the intervening member and suppress the temperature of the adjacent energy storage device from rising.

[0008] Examples of the "energy storage device" include secondary batteries such as lithium-ion secondary batteries, sodium-ion secondary batteries, and calcium-ion secondary batteries, and capacitors such as lithium-ion capacitors. The "top contact portion" can be formed by, for example, the following methods. That is, the top contact portion having a large number of convex portions can be formed by subjecting the contact portion of the outer surface of the case to a physical surface roughening treatment such as shot blasting, sand blasting, or metal spraying, a chemical surface roughening treatment such as anodizing or chemical etching, or a surface roughening treatment for forming convex portions on the nano order by irradiation with a pulsed laser. Alternatively, a top contact portion having a large number of convex portions can also be formed by pressing. Further, the top contact portion may be formed only on a part of the contact portion of the outer surface of the case, or may be formed on the entire contact portion. Also, on the portion of the outer surface of the case other than the contact portion, a number of convex portions similar to the number of convex portions of the top contact portion may be formed.

[0009] Examples of the "intermediate member" include an intermediate member made of resin or metal. Alternatively, an intermediate member made of an elastic body such as rubber or elastomer may be used, and the portion of the intermediate member that contacts the top contact portion is deformed such that when the top of the convex portion contacts it, it is recessed to cover the top of the convex portion, etc., so that the hardness is such that an increase in the contact area with the convex portion can be suppressed. Also, the intermediate member disposed between adjacent power storage devices may be single or plural. Examples of the form of the intermediate member include a plate-shaped intermediate member, and an intermediate member having an intermediate main body portion such as a plate shape and an intermediate convex portion that protrudes from the intermediate main body portion toward the contact portion of the power storage device and contacts the contact portion. In the latter intermediate member, a cooling path through which a cooling medium such as cooling air flows can also be formed between the intermediate main body portion and the power storage device.

[0010] (2) The power storage device module according to (1), wherein it is preferable that the power storage device module having a number of the convex portions is provided only on the contact portion of the outer surface of the case.

[0011] In the above-described power storage device module, since it is not necessary to provide a number of convex portions on the portion of the outer surface of the case other than the contact portion, an inexpensive power storage device and an inexpensive power storage device module can be obtained while ensuring heat insulation with the intermediate member.

[0012] (3) The power storage device module according to (1), wherein the intervening member has an intervening main body portion disposed between adjacent power storage devices, and an intervening convex portion that protrudes from the intervening main body portion toward the contact portion of the power storage device and contacts the contact portion. The outer surface of the case of the power storage device includes, in addition to the contact portion, a spaced-apart opposing portion that faces the intervening main body portion while being spaced apart therefrom, and forms a cooling passage therebetween. The spaced-apart opposing portion also has a plurality of convex portions, and these convex portions increase the surface area facing the cooling passage. It is preferable that the power storage device module is formed in this way.

[0013] In the above-described power storage device module, a cooling passage for allowing a cooling medium such as cooling air to flow is formed between the intervening main body portion of the intervening member and the spaced-apart opposing portion of the outer surface of the case of the power storage device, and a plurality of convex portions are also provided on the spaced-apart opposing portion. The plurality of convex portions provided on this spaced-apart opposing portion have the same form as the plurality of convex portions of the contact portion, but their functions are different. That is, the plurality of convex portions of the spaced-apart opposing portion increase the surface area facing the cooling passage (increase the surface area of the spaced-apart opposing portion compared to the surface area when the spaced-apart opposing portion is flat without convex portions, that is, the planar area of the spaced-apart opposing portion), and can efficiently dissipate the heat of the power storage device through the spaced-apart opposing portion. Therefore, in the above-described power storage device module, among the outer surface of the case, at the contact portion, the heat of the power storage device can be suppressed from being transmitted to adjacent power storage devices (heat insulation of the power storage device), while at the spaced-apart opposing portion, the heat of the power storage device can be efficiently dissipated. In addition, since the plurality of convex portions of the contact portion and the plurality of convex portions of the spaced-apart opposing portion have the same form, there is also an advantage that they can be formed at once by the same method when forming a plurality of convex portions on the outer surface of the case.

Brief Description of the Drawings

[0014]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Mode for Carrying Out the Invention

[0015] (Embodiment 1) Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows a perspective view of a battery (power storage device) 1 that constitutes a battery module (power storage device module) 500 of the present embodiment, FIG. 2 shows a side view of the battery 1 on the side of the first wide side surface 14, and FIG. 3 shows a side view of the battery 1 on the side of the second wide side surface 15. FIG. 4 shows a partial cross-sectional view of the battery module 500, and FIG. 5 further shows part A of FIG. 4. Hereinafter, the battery height direction AH, the battery width direction BH, and the battery thickness direction CH of the battery 1 are defined as the directions shown in FIGS. 1 to 3, and the vertical direction DH and the column arrangement direction EH of the battery module 500 are defined as the directions shown in FIGS. 4 and 5 for explanation.

[0016] The battery module 500 is mounted on vehicles such as hybrid cars, plug-in hybrid cars, and electric vehicles. The battery module 500 includes a plurality of batteries 1. The battery 1 is a rectangular (cuboid-shaped) sealed lithium-ion secondary battery, and is composed of a case 10, an electrode body 40 and an electrolytic solution 5 housed in the case 10, a positive electrode terminal 50 and a negative electrode terminal 60 supported by the case 10, etc. (see FIGS. 1 to 3).

[0017] The case 10 is in the shape of a rectangular parallelepiped box made of metal (aluminum in this embodiment), has a bottomed rectangular tube shape with a rectangular opening 31c, and is composed of a case body member 31 that houses the electrode body 40 inside and a rectangular plate-shaped case lid member 32 that closes the opening 31c of the case body member 31. The opening 31c of the case body member 31 and the peripheral edge 32f of the case lid member 32 are hermetically welded over the entire circumference. The case lid member 32 is provided with a safety valve 35 that breaks and opens when the internal pressure of the case 10 exceeds the opening pressure. Further, the case lid member 32 is provided with a liquid injection hole 32k, and this liquid injection hole 32k is hermetically sealed with a disc-shaped sealing member 36 made of aluminum.

[0018] Also, in the case lid member 32, near the ends of one side BH1 and the other side BH2 in the battery width direction BH, rectangular insertion holes (not shown) are provided respectively. Inside the insertion hole on one side BH1, a positive electrode terminal 50 made of aluminum is inserted, and the positive electrode terminal 50 is fixed to the case lid member 32 in a state of being insulated from the case lid member 32 via a resin member 55. The positive electrode terminal 50 is welded to a positive electrode current collecting portion 40c (to be described later) of the electrode body 40 at the tip of the lower side AH2 in the battery height direction AH and is conductively connected to the positive electrode current collecting portion 40c. Also, inside the insertion hole on the other side BH2, a negative electrode terminal 60 made of copper is inserted, and the negative electrode terminal 60 is fixed to the case lid member 32 in a state of being insulated from the case lid member 32 via a resin member 65. The negative electrode terminal 60 is welded to a negative electrode current collecting portion 40d (to be described later) of the electrode body 40 at the tip of the lower side AH2 and is conductively connected to the negative electrode current collecting portion 40d.

[0019] The electrode body 40 has a rectangular parallelepiped shape and is of a stacked type, in which a plurality of rectangular positive electrode plates 41 and a plurality of rectangular negative electrode plates 42 are alternately stacked in the battery thickness direction CH via a rectangular separator 43 made of a resin porous film. In one side BH1 of the battery width direction BH of the electrode body 40, the current collecting foils of the respective positive electrode plates 41 overlap in the battery thickness direction CH to form a positive electrode current collecting portion 40c. This positive electrode current collecting portion 40c is conductively connected to the positive electrode terminal 50. Also, in the other side BH2 of the battery width direction BH of the electrode body 40, the current collecting foils of the respective negative electrode plates 42 overlap in the battery thickness direction CH to form a negative electrode current collecting portion 40d. This negative electrode current collecting portion 40d is conductively connected to the negative electrode terminal 60.

[0020] Next, regarding the case outer surface 11 of the case 10 that is exposed to the outside of the case 10, details will be described (see FIGS. 1 to 3). The case 10 has a rectangular parallelepiped box shape, and the case outer surface 11 has an upper surface 12, a lower surface 13, a first wide side surface 14, a second wide side surface 15, a first narrow side surface 16, and a second narrow side surface 17, each of which has a rectangular shape. The upper surface 12 is located on the upper side AH1 in the battery height direction AH, and the lower surface 13 is located on the lower side AH2. The first wide side surface 14 and the second wide side surface 15 have a larger area than the first narrow side surface 16 and the second narrow side surface 17. The first wide side surface 14 is located on one side CH1 in the battery thickness direction CH, and the second wide side surface 15 is located on the other side CH2 in the battery thickness direction CH. Also, the first narrow side surface 16 is located on one side BH1 in the battery width direction BH, and the second narrow side surface 17 is located on the other side BH2 in the battery width direction BH.

[0021] The case outer surface 11 has a first contact portion (hereinafter, also simply referred to as "contact portion") 21 and a second contact portion (hereinafter, also simply referred to as "contact portion") 22 that come into contact with an intervening member 520 (see FIGS. 4 and 5) described later. The first contact portion 21 is a rectangular central portion excluding the peripheral portion of the first wide side surface 14 of the outer surface 11 of the case (see FIG. 2). This first contact portion 21 includes a first top contact portion (hereinafter, also simply referred to as the "top contact portion") 23 formed with a number of convex portions 11t (indicated by dots in FIG. 2). Specifically, in the first embodiment, the entire first contact portion 21 serves as the first top contact portion 23. As will be described later, since only the tops 11tp of the number of convex portions 11t of the first top contact portion 23 contact the intervening member 520 (see FIG. 5), the contact area Sta between the first top contact portion 23 and the intervening member 520 is reduced as compared with the case where the number of convex portions 11t is not provided.

[0022] In the first embodiment, the first top contact portion 23 having a number of convex portions 11t and the second top contact portion 24 having a number of convex portions 11t to be described later are formed by metal spraying. However, they can also be formed by other physical or chemical surface roughening treatments or surface roughening treatments for forming convex portions on the nano order by irradiation with pulsed laser light.

[0023] The second contact portion 22 is a rectangular central portion excluding the peripheral portion of the second wide side surface 15 of the outer surface 11 of the case (see FIG. 3). Similar to the first top contact portion 23 of the first contact portion 21, this second contact portion 22 also includes a second top contact portion (hereinafter, also simply referred to as the top contact portion) 24 formed with a number of convex portions 11t (indicated by dots in FIG. 3). Since only the tops 11tp of the number of convex portions 11t of the second top contact portion 24 contact the intervening member 520 as will be described later (see FIG. 5), the contact area Stb between the second top contact portion 24 and the intervening member 520 is reduced as compared with the case where the number of convex portions 11t is not provided. In the first embodiment, the number of convex portions 11t is provided only on the first contact portion 21 and the second contact portion 22 of the outer surface 11 of the case. That is, there are no number of convex portions 11t on the upper surface 12, the lower surface 13, the peripheral portion of the first wide side surface 14, the peripheral portion of the second wide side surface 15, the first narrow side surface 16, and the second narrow side surface 17.

[0024] Next, a battery module 500 including a plurality of the above-described batteries 1 will be described (see FIGS. 4 and 5). The battery module 500 includes a plurality of batteries 1 stacked in a row in the juxtaposition direction EH with the battery height direction AH coinciding with the vertical direction DH of the battery module 500 and the battery thickness direction CH coinciding with the juxtaposition direction EH, a plurality of intervening members 520 respectively disposed between adjacent batteries 1 in the juxtaposition direction EH, and a module case 510 that houses these batteries 1 and intervening members 520.

[0025] The module case 510 is made of resin and has a rectangular opening and is an angular cylindrical shape. This module case 510 restrains a plurality of batteries 1 arranged in a row in the juxtaposition direction EH and a plurality of intervening members 520 in the juxtaposition direction EH. For each battery 1 housed in the module case 510, one side CH1 in the battery thickness direction CH coincides with one side CH1 in the juxtaposition direction EH (the right side in FIGS. 4 and 5), that is, the first wide side surface 14 is located on one side CH1 in the juxtaposition direction EH, and the other side CH2 in the battery thickness direction CH coincides with the other side CH2 in the juxtaposition direction EH (the left side in FIGS. 4 and 5), that is, the second wide side surface 15 is located on the other side CH2 in the juxtaposition direction EH. The positive terminals 50 and the negative terminals 60 of adjacent batteries 1 are electrically connected via busbars (conductive connection members) 530, respectively, and the batteries 1 constituting the battery module 500 are connected in parallel. The busbar 530 has a rectangular plate shape, and the busbar 530 and the positive terminal 50 or the negative terminal 60 are joined by welding.

[0026] Next, the intervening member 520 will be described. This intervening member 520 is disposed between adjacent batteries 1 and also between the module case 510 and the battery 1. The intervening member 520 is a rectangular plate made of an insulating elastic body (ethylene propylene diene rubber (EPDM) in the first embodiment) and has a sticky first main surface 520a and a second main surface 520b with an area smaller than the first wide side surface 14 and the second wide side surface 15 of the battery 1. Each intervening member 520 is disposed such that the first main surface 520a is located on the other side CH2 in the juxtaposition direction EH and the second main surface 520b is located on one side CH1 in the juxtaposition direction EH.

[0027] The first main surface 520a of the intervening member 520 is in contact with the first contact portion 21 (first top contact portion 23) of the first wide side surface 14 among the outer surface 11 of the case of the battery 1 located on the other side EH2 of the arrangement direction EH of the intervening member 520. That is, a large number of convex portions 11t provided on the first top contact portion 23 of the battery 1 abut on the first main surface 520a of the intervening member 520 at their tops 11tp, so that the first contact portion 21 of the battery 1 and the first main surface 520a of the intervening member 520 are in contact. The contact area Sta between the first top contact portion 23 of the battery 1 and the first main surface 520a of the intervening member 520 is smaller than the contact area when the first top contact portion 23 is flat without the convex portions 11t, that is, smaller than the planar area Soa of the first top contact portion 23 (Sta < Soa). Specifically, the contact area Sta between the first top contact portion 23 and the first main surface 520a is approximately one-tenth of the planar area Soa of the first top contact portion 23. Therefore, the heat conduction from the first contact portion 21 of the first wide side surface 14 of the battery 1 to the first main surface 520a of the intervening member 520 is low.

[0028] Also, the second main surface 520b of the intervening member 520 is in contact with the second contact portion 22 (second top contact portion 24) of the second wide side surface 15 among the outer surface 11 of the case of the battery 1 located on one side EH1 of the arrangement direction EH of the intervening member 520. That is, a large number of convex portions 11t provided on the second top contact portion 24 of the battery 1 abut on the second main surface 520b of the intervening member 520 at their tops 11tp, so that the second contact portion 22 of the battery 1 and the second main surface 520b of the intervening member 520 are in contact. The contact area Stb between the second top contact portion 24 of the battery 1 and the second main surface 520b of the intervening member 520 is smaller than the contact area when the second top contact portion 24 is flat without the convex portions 11t, that is, smaller than the planar area Sob of the second top contact portion 24 (Stb < Sob). Specifically, the contact area Stb between the second top contact portion 24 and the second main surface 520b is approximately one-tenth of the planar area Sob of the second top contact portion 24. Therefore, the heat conduction from the second contact portion 22 of the second wide side surface 15 of the battery 1 to the second main surface 520b of the intervening member 520 is low.

[0029] In the battery module 500 of the first embodiment, the contact portions 21 and 22 on the outer surface 11 of the case of the battery 1 each include top contact portions 23 and 24 in which the contact areas Sta and Stb with the intervening member 520 are reduced by a number of convex portions 11t, and the contact portions 21 and 22 of the battery 1 and the intervening member 520 are in contact with each other in a small area. Therefore, compared with the case where the contact portions 21 and 22 of the battery 1 do not have the top contact portions 23 and 24, the heat conduction from the contact portions 21 and 22 of the battery 1 to the intervening member 520 can be reduced. Thereby, when a certain battery 1 generates heat, it is possible to suppress the heat from being transmitted to the adjacent battery 1 through the intervening member 520 and suppress the temperature of the adjacent battery 1 from rising. Furthermore, in the first embodiment, a number of convex portions 11t are provided only on the contact portions 21 and 22 of the outer surface 11 of the case of the battery 1. Therefore, it is not necessary to provide a number of convex portions 11t on the portions of the outer surface 11 of the case other than the contact portions 21 and 22, so that an inexpensive battery 1 and an inexpensive battery module 500 can be obtained while ensuring heat insulation from the intervening member 520.

[0030] (Second Embodiment) Next, a second embodiment will be described (see FIGS. 6 and 7). Note that the description of the same parts as in the first embodiment will be omitted or simplified. In the battery module 500 of the first embodiment, a rectangular plate-shaped intervening member 520 is used. In contrast, in the battery module 600 of the second embodiment, an intervening member 620 having an intervening main body portion 622 and a plurality of intervening convex portions 623 is used, and a cooling path 640 for allowing cooling air to flow is formed between the battery 100 and the intervening member 620. Also, in the battery 100 of the second embodiment, the range (region) in which a number of convex portions 11t are formed on the outer surface 11 of the case is different from that of the battery 1 of the first embodiment.

[0031] The outer surface 11 of the case of the battery 100 according to the second embodiment has a first contact portion 121 and a second contact portion 22 that contact the intervening member 620. The first contact portion 121 is a portion of the first wide side surface 14 of the case outer surface 11 where a plurality of intervening convex portions 623 of the intervening member 620 come into contact. This first contact portion 121 includes a first top contact portion 123 formed with a large number of convex portions 11t. Specifically, the entire first contact portion 121 serves as the first top contact portion 123. The large number of convex portions 11t themselves are the same as the large number of convex portions 11t in Embodiment 1. Since only the tops 11tp of the large number of convex portions 11t of the first top contact portion 123 contact the top surface 623m of the intervening convex portions 623 of the intervening member 620, the contact area Sta between the first top contact portion 123 and the intervening member 620 is reduced compared to the planar area Soa of the first top contact portion 123 (Sta < Soa). Also, the second contact portion 22 is the same as the second contact portion 22 in Embodiment 1 and includes a second top contact portion 24 formed with a large number of convex portions 11t. Therefore, the contact area Stb between the second top contact portion 24 and the intervening member 620 is reduced compared to the planar area Sob of the second top contact portion 24 (Stb < Sob).

[0032] On the other hand, in the present Embodiment 2, a large number of convex portions 11t are also provided at sites on the case outer surface 11 other than the first contact portion 121 and the second contact portion 22. That is, the first wide side surface 14 of the case outer surface 11 faces the intervening main body portion 622 of the intervening member 620 while being separated therefrom, and includes a separated opposing portion 125 that forms a cooling path 640 between the intervening main body portion 622. And a large number of convex portions 11t are also formed on this separated opposing portion 125. The surface area Sh of this separated opposing portion 125 is larger than the planar area Soh when the separated opposing portion 125 is flat without the convex portions 11t provided thereon (Sh > Soh). Therefore, the heat dissipation from the separated opposing portion 125 of the first wide side surface 14 of the battery 1 to the cooling path 640 is good. Note that the surface area Sh of the separated opposing portion 125 can be obtained by a gas adsorption method using Kr gas.

[0033] Also, in the present Embodiment 2, a large number of convex portions 11t are also formed on the peripheral portion (the peripheral edge portion of the first wide side surface 14) of the first wide side surface 14 of the case outer surface 11, that is, the first contact portion 121 and the separated opposing portion 125. That is, in the present Embodiment 2, a large number of convex portions 11t are formed over the entire surface of the first wide side surface 14. Also, among the second wide side surfaces 15 of the case outer surface 11, a large number of convex portions 11t are also formed around the second contact portion 22 (the peripheral portion of the second wide side surface 15). That is, in the second embodiment, a large number of convex portions 11t are formed over the entire surface of the second wide side surface 15.

[0034] The intervening member 620 of the second embodiment includes a rectangular plate-like intervening main body portion 622 disposed between adjacent batteries 100, and a plurality of intervening convex portions 623 that project from the intervening main body portion 622 toward the first contact portion 121 of the battery 100 located on the other side EH2 in the arrangement direction EH of the intervening members 620 and contact the first contact portion 121. The intervening main body portion 622 has a first main surface 622a and a second main surface 622b that are smaller in area than the first wide side surface 14 and the second wide side surface 15 of the battery 100. This intervening member 620 is integrally formed of an insulating resin.

[0035] Regarding the relationship between the intervening member 620 and the battery 100 located on the other side EH2 in the arrangement direction EH of the intervening members 620, the plurality of intervening convex portions 623 are respectively in contact with a plurality of first contact portions 121 (first top contact portions 123) among the first wide side surfaces 14 of the case outer surface 11. That is, a large number of convex portions 11t provided on the first top contact portion 123 abut against the top surface 623m of the intervening convex portion 623 at their tops 11tp, so that the first contact portion 121 and the intervening convex portion 623 are in contact with each other with a small area. Also, the first main surface 622a of the intervening main body portion 622 faces the first wide side surface 14 of the case outer surface 11 while being separated from the spaced-apart opposing portion 125, and constitutes the cooling channel 640 described above between the spaced-apart opposing portion 125.

[0036] Looking at the relationship between one side, the intervening member 620, and the battery 100 located on one side EH1 of the arrangement direction EH of the intervening member 620, the second main surface 622b of the intervening main body portion 622 is in contact with the second contact portion 22 (the second top contact portion 24) of the second wide side surface 15 of the case outer surface 11. That is, a large number of convex portions 11t provided on the second top contact portion 24 contact the second main surface 622b of the intervening main body portion 622 at their tops 11tp, so that the second contact portion 22 and the second main surface 622b of the intervening main body portion 622 are in contact with a small area.

[0037] In the battery module 600 of the second embodiment, the contact portions 121, 22 of the case outer surface 11 of the battery 100 each include top contact portions 123, 24 in which the contact areas Sta, Stb with the intervening member 620 are reduced by a large number of convex portions 11t, and the contact portions 121, 22 of the battery 100 and the intervening member 620 are in contact with each other with a small area. For this reason, the heat conduction from the contact portions 121, 22 of the battery 100 to the intervening member 620 can be lowered, and when a certain battery 100 generates heat, it is possible to suppress this heat from being transmitted to the adjacent battery 100 through the intervening member 620.

[0038] Also, in the second embodiment, a cooling path 640 is formed between the intervening main body portion 622 of the intervening member 620 and the spaced-apart opposing portion 125 of the case outer surface 11 of the battery 100, and a large number of convex portions 11t are also provided on the spaced-apart opposing portion 125. The large number of convex portions 11t provided on the spaced-apart opposing portion 125 have the same form as the large number of convex portions 11t of the contact portions 121, 22, but their functions are different. That is, the large number of convex portions 11t of the spaced-apart opposing portion 125 increase the surface area Sh facing the cooling path 640, and the heat of the battery 100 can be efficiently dissipated through the spaced-apart opposing portion 125. For this reason, in the battery module 600, among the case outer surface 11, at the contact portions 121, 22, it is possible to suppress the heat of the battery 100 from being transmitted to the adjacent battery 100 (insulate the heat of the battery 100), while at the spaced-apart opposing portion 125, the heat of the battery 100 can be efficiently dissipated. In addition, since the numerous convex portions 11t of the contact portions 121 and 22 and the numerous convex portions 11t of the spaced-apart opposing portion 125 have a similar form, when forming the numerous convex portions 11t on the outer surface 11 of the case, there is also an advantage that they can be formed at once by the same method (metal spraying in the second embodiment). In addition, parts similar to those in the first embodiment have the same functions and effects as those in the first embodiment.

[0039] (Embodiment 3) Next, a third embodiment will be described (see FIGS. 8 and 7). Note that descriptions of parts similar to those in the first or second embodiment will be omitted or simplified. The battery module 700 of the third embodiment has a form in which the intervening member 720 is composed of an intervening main body portion 722 and intervening convex portions 723, similar to the intervening member 620 of the second embodiment. However, the intervening member 720 of the third embodiment is different from the intervening member 620 of the second embodiment in that it is formed by overlapping two members, namely, a first intervening member 725 and a second intervening member 726. In FIG. 7, the boundary between the first intervening member 725 and the second intervening member 726 is indicated by a dashed line.

[0040] The battery 100 according to the third embodiment is the same as the battery 100 according to the second embodiment. That is, the outer surface 11 of the case of the battery 100 has a first contact portion 121 and a second contact portion 22. The first contact portion 121 is composed of a first top contact portion 123 having a number of convex portions 11t, and contacts the top surface 723m of the intervening convex portion 723 of the intervening member 720 with a small contact area Sta. The second contact portion 22 is composed of a second top contact portion 24 having a number of convex portions 11t, and contacts the second main surface 722b of the intervening main body portion 722 of the intervening member 720 with a small contact area Stb. The outer surface 11 of the case faces the intervening main body portion 722 of the intervening member 720 while being spaced apart, and includes a spaced-apart opposing portion 125 that forms a cooling path 640 between the intervening main body portion 722, and a number of convex portions 11t are also formed on this spaced-apart opposing portion 125.

[0041] The intervening member 720 according to the third embodiment is composed of a first intervening member 725 and a second intervening member 726, respectively. The first intermediate member 725 has a rectangular plate-shaped first main body portion 725e and a plurality of first convex portions 725g that protrude from the first main body portion 725e and form a plurality of intermediate convex portions 723 of the intermediate member 720. This first intermediate member 725 is made of resin, similar to the intermediate member 620 of the second embodiment. The second intermediate member 726 is rectangular plate-shaped and is made of rubber, similar to the intermediate member 520 of the first embodiment. The first main body portion 725e of the second intermediate member 726 and the first intermediate member 725 overlap in the column direction EH to form the intermediate main body portion 722 of the intermediate member 720. The intermediate main body portion 722 is rectangular plate-shaped and has a first main surface 722a and a second main surface 722b.

[0042] In the battery module 700 of the third embodiment, the contact portions 121 and 22 on the outer surface 11 of the case of the battery 100 each include top contact portions 123 and 24 in which the contact areas Sta and Stb with the intermediate member 720 are reduced by a number of convex portions 11t, and the contact portions 121 and 22 of the battery 100 and the intermediate member 720 are in contact with each other in a small area. Therefore, the heat conduction from the contact portions 121 and 22 of the battery 100 to the intermediate member 720 can be reduced, and when a certain battery 100 generates heat, it is possible to suppress the heat from being transmitted to the adjacent battery 100 through the intermediate member 720. In addition, the same parts as in the first or second embodiment have the same operational effects as in the first or second embodiment.

[0043] As described above, the present invention has been described with reference to the first to third embodiments, but the present invention is not limited to the first to third embodiments, and it goes without saying that it can be appropriately modified and applied without departing from the gist thereof. For example, in the first to third embodiments, the battery modules 500, 600, and 700 in which a plurality of batteries 1 and 100 are stacked in a row are illustrated, but a battery module in which a plurality of batteries 1 and 100 are stacked in a plurality of rows may also be used. Also, in the first to third embodiments, a plurality of batteries 1 and 100 forming the battery modules 500, 600, and 700 are connected in parallel, but the electrical connection between the batteries 1 and 100 is not limited to this, and the batteries 1 and 100 may be connected in series.

Explanation of Reference Numerals

[0044] 1,100 batteries (electric storage devices) 10 cases 11 outer surface of the case 11t convex portion 11tp top (of the convex portion) 21,121 first contact portion 22 second contact portion 23,123 first top contact portion 24 second top contact portion 125 spaced-apart opposing portion 40 electrode body 500,600,700 battery modules (electric storage device modules) 510 module case 520,620,720 intervening members 622,722 intervening main body portions 623,723 intervening convex portions 640 cooling path Sta contact area (between the first top contact portion and the intervening member) Stb contact area (between the second top contact portion and the intervening member) Sh surface area (of the spaced-apart opposing portion)

Claims

1. A plurality of energy storage devices arranged in a row, and an intervening member interposed between adjacent ones of the energy storage devices, comprising: each of the energy storage devices includes an electrode body and a metal case that houses the electrode body, the case has an outer case surface that is exposed to the outside, the outer case surface includes a contact portion that contacts the intervening member an energy storage device module, the contact portion of the outer case surface has a large number of convex portions, and a top contact portion is formed in which the tops of these convex portions abut against the intervening member to reduce the contact area with the intervening member an energy storage device module.

2. The energy storage device module according to claim 1, wherein only the contact portion of the outer case surface has a large number of the convex portions an energy storage device module.

3. The energy storage device module according to claim 1, wherein the intervening member has an intervening main body portion disposed between adjacent ones of the energy storage devices, and an intervening convex portion that protrudes from the intervening main body portion toward the contact portion of the energy storage device and contacts the contact portion, the outer case surface of the energy storage device in addition to the contact portion, includes a spaced-apart opposing portion that faces the intervening main body portion while being spaced apart from the intervening main body portion and forms a cooling passage therebetween, the spaced-apart opposing portion also has a large number of the convex portions, and these convex portions increase the surface area facing the cooling passage an energy storage device module.

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