Battery module and battery pack

Abstract

Provided are a battery module and a battery pack which are highly water resistant and capable of maintaining the storage of a battery in a storage part even when vibrations or impacts are applied. A battery module 10 according to the present disclosure comprises: a cylindrical battery 11; and a battery holder 20 which is in the form of a single elastic body and houses and holds the battery 11. The battery holder 20 has a storage part 21 for storing the battery 11. Both ends of the storage part 21 have an extension part 22 extending toward an axis AX of the battery 11, and an opening 23 surrounded by the extension part 22.

Description

Battery modules and battery packs

[0001] The present disclosure relates to a battery module and a battery pack.

[0002] Patent Document 1 discloses a battery pack that includes a battery and a battery holder having a battery storage section for storing the battery, the battery holder having an insertion hole on its side into which the battery is inserted from the positive side, the diameter of the insertion hole being larger than the diameter of the bottom circle of the battery stored in the battery storage section.

[0003] International Publication No. 2018 / 150672

[0004] The battery pack described in Patent Document 1 has an insertion hole that is larger than the diameter of the bottom circle of the battery, so if the battery pack is submerged in water, there is a possibility that water may seep in through the insertion hole. Also, if the battery pack is subjected to vibration or impact, there is a possibility that the battery may come out of the insertion hole or move significantly in the axial direction within the battery housing, making it impossible to maintain the battery storage.

[0005] The present disclosure has been made in light of this viewpoint, and a primary objective of the present disclosure is to provide a battery module and a battery pack that are highly waterproof and capable of maintaining the batteries housed within the battery housing even when subjected to vibrations or impacts.

[0006] The battery module of the present disclosure comprises a cylindrical battery and a battery holder that is an integral part made of an elastic body and that houses and holds the battery. The battery holder has a storage section that houses the battery, and at both ends of the storage section, there are extension sections that extend toward the axis of the battery and openings that are surrounded by the extension sections.

[0007] The battery pack of the present disclosure includes the above-described battery module.

[0008] According to the present disclosure, the waterproofing is high, and the battery can be maintained inside the battery housing even when vibration or impact is applied.

[0009] FIG. 1 is a schematic exploded perspective view of a battery pack according to the present disclosure. FIG. 2 is a schematic exploded perspective view of a battery module housed in the battery pack according to the present disclosure. FIG. 3 is a schematic cross-sectional view of a battery module according to the present disclosure. FIGS. 4(a) to 4(c) are cross-sectional views illustrating steps in manufacturing the battery module according to the present disclosure. FIG. 5A is a schematic cross-sectional view of an embodiment in which a tab is provided on the battery module according to the present disclosure. FIG. 5B is an enlarged schematic cross-sectional view of the periphery of the convex portion of FIG. 5A. FIG. 5C is an enlarged schematic cross-sectional view showing a modified convex portion. FIG. 5D is an enlarged schematic cross-sectional view showing a further modified convex portion. FIG. 6A is a schematic cross-sectional view of a modified battery module according to the present disclosure. FIG. 6B is an enlarged schematic cross-sectional view of the periphery of the extension portion of FIG. 6A. FIG. 7A is a schematic cross-sectional view of another modified battery module according to the present disclosure. FIG. 7B is an enlarged schematic cross-sectional view of the periphery of the extension portion of FIG. 6A. FIG. 8 is a schematic cross-sectional view of another modified battery module according to the present disclosure. FIG. 9A is an enlarged schematic cross-sectional view of another modified battery module according to the present disclosure. FIG. 9B is a schematic enlarged cross-sectional view of another modified example of the battery module of the present disclosure in which tabs are provided.

[0010] A battery pack according to an embodiment of the present disclosure will be described in more detail below. While the description will be made with reference to drawings as needed, the various elements in the drawings are merely shown schematically and for illustrative purposes to facilitate understanding of the present disclosure, and the appearance and dimensional ratios may differ from those of the actual product.

[0011] As used herein, the term "plan view" refers to the state when an object (e.g., a battery pack) is placed and viewed from directly above in the thickness (height) direction, and is synonymous with a plan view. For example, the term "plan view" refers to the state when viewed along the positive direction in the "Z direction" shown in FIG. 1 . Unless otherwise specified, the term "side view" refers to the state when an object (e.g., a battery pack) is placed and viewed from the side perpendicular to the thickness (height) direction, and is synonymous with a side view. For example, the term "side view" refers to the state when viewed along the positive (or negative) direction in the "X direction" shown in FIG. 1 . Unless otherwise specified, the term "front view" refers to the state when an object (e.g., a battery pack) is placed and viewed from the front perpendicular to the thickness (height) direction, and is synonymous with a front view. For example, the term "front view" refers to the state when viewed along the positive direction in the "Y direction" shown in FIG. 1 . The "positive direction" mentioned above refers to the directions of the X, Y, and Z arrows shown in the drawings, and the "negative direction" refers to the direction opposite to the X, Y, and Z arrows shown in the drawings. The X, Y, and Z directions are perpendicular to each other. In addition, the terms "about" and "approximately" used in this specification mean that there may be a variation of a few percent, for example, ±10%.

[0012] [Battery Pack] A battery pack 1 of the present disclosure will be described with reference to Fig. 1. Fig. 1 is a schematic exploded perspective view of the battery pack 1.

[0013] The battery pack 1 may include a case CS and a battery module 10 housed in the case CS (see FIGS. 1 and 2). The battery module 10 will be described in detail below.

[0014] The case CS may be configured by a first case CS1 and a second case CS2. The first case CS1 and the second case CS2 may form a storage space that houses the battery module 10. Note that, although the example in FIG. 1 illustrates a mode in which the storage space is formed by two cases (the first case CS1 and the second case CS2), the present invention is not limited to this mode, and the storage space may be formed by three or more cases.

[0015] The case CS may be made of any material, including a resin material (e.g., plastic) or a metal material. Examples of resin materials include polycarbonate (PC), acrylonitrile butadiene styrene (ABS), polybutylene terephthalate (PBT), modified polyphenylene ether (m-PPE), and polyamide (PA). Examples of metal materials include aluminum. To more appropriately accommodate the battery module 10, a highly rigid material may be used for the case CS.

[0016] The case CS may be provided with a connector CN that is electrically connected to the battery module 10. In the example shown in Fig. 1, the connector CN is provided on the second case CS2, but the connector CN may also be provided on the first case CS1. The connector CN may be a terminal for extracting power from the battery module 10.

[0017] [Battery Module] The battery module 10 of the present disclosure will be described with reference to Figures 2 to 5D. Figure 2 is a schematic exploded perspective view of the battery module 10 housed in the battery pack 1 of the present disclosure, Figure 3 is a schematic cross-sectional view of the battery module 10 of the present disclosure, Figures 4(a) to 4(c) are cross-sectional views illustrating the manufacturing process of the battery module 10 of the present disclosure, Figure 5A is a schematic cross-sectional view of an embodiment in which a tab is provided on the battery module of the present disclosure, Figure 5B is an enlarged schematic cross-sectional view of the periphery of the convex portion of Figure 5A, Figure 5C is an enlarged schematic cross-sectional view showing a modified example of the convex portion, and Figure 5D is an enlarged schematic cross-sectional view showing a further modified example of the convex portion.

[0018] The battery module 10 of the present disclosure includes a battery 11 and a battery holder 20 (see FIG. 2). More preferably, the battery module 10 of the present disclosure may include a tab TB and a control board SB. The components constituting the battery module 10 of the present disclosure will be described in detail below with reference to the drawings.

[0019] -Battery- The battery 11 is intended to be a chemical battery that converts mainly chemical energy into direct current power through a chemical reaction. The battery 11 used in the battery module 10 of the present disclosure is intended to be a cylindrical battery with a cylindrical axis AX in the ±Y direction. Note that the shape of the battery may be a shape other than a cylindrical shape (for example, an elliptical cylinder or a polygonal cylinder).

[0020] The battery module 10 of the present disclosure may include two or more batteries 11. The batteries 11 may be arranged adjacent to each other. For example, in the embodiment shown in Fig. 2, four batteries 11 may be arranged adjacent to each other in the ±X directions and stacked in two rows in the +Z direction.

[0021] The battery 11 may have a positive terminal 12 on one side of the axis AX of the battery 11 and a negative terminal 13 on the opposite side (see FIG. 3 ). When viewed along the Y direction, the positive terminal 12 and the negative terminal 13 have a circular shape corresponding to the cylindrical shape of the battery 11. The positive terminal 12 may have a positive electrode surface 12a that protrudes from the terminal surface of the battery 11. Specifically, when viewed along the Y direction, the positive electrode surface 12a may be located in the center of the positive terminal 12. Note that the positive electrode surface 12a may have a circular shape, and the center of the positive electrode surface 12a may coincide with the center of the positive terminal 12. In the embodiment shown in FIG. 3 , the positive electrode surface 12a may protrude from the terminal surface of the battery 11 in the +Y direction.

[0022] - Battery Holder - The battery holder 20 is a one-piece molded product made of an elastic material and includes a housing portion 21 for housing the above-described battery 11 (see Figure 3). As used herein, the term "one-piece molded product" refers to a molded product constructed of the same continuous material by punching out the molding material using a die or other tool. In other words, it refers to a molded product without any joints formed by welding or mechanical joining. The one-piece molded battery holder 20 houses the above-described multiple batteries 11 side by side. Therefore, even if gas escapes from a battery 11, unlike battery holders with joints, the escaped gas is prevented from directly spraying onto adjacent batteries. In other words, it is effective against induced explosions in the event of an abnormality. In other words, it has excellent resistance to induced explosions. The elastic material constituting the battery holder 20 is, for example, silicone rubber and / or elastomer. Any elastic material can be selected as the elastic material. Specifically, a material may be used that has an elongation [%] of 100 to 1000, a Young's modulus [GPa] of 0.01 to 10, and a Poisson's ratio of 0.3 to 0.5. Examples of such materials include natural rubber, butyl rubber, fluororubber, ethylene propylene rubber, chloroprene rubber, and acrylonitrile rubber. In this specification, 0% elongation refers to the original length of the elastic body.

[0023] The housing section 21 has extensions 22 at both ends that extend toward the axis AX of the battery 11, and openings 23 surrounded by the extensions 22. In the embodiment shown in FIG. 3 , the extensions 22 extend in the ±Z and ±X directions toward the axis AX of the battery 11. Specifically, the extensions 22 extend in the ±Z and ±X directions toward the axis AX of the battery 11 from the point where they contact the housing section 21. When the battery 11 is housed in this housing section 21, the battery 11 can be housed therein with the positive electrode surface 12a and negative terminal 13 exposed through the openings 23. Therefore, the entire periphery of the battery 11, except for the positive electrode surface 12a and negative terminal 13, is covered by the battery holder 20, which is an integrally molded elastic member. The battery holder 20's elasticity allows it to tightly fit the battery 11, improving waterproofing. Furthermore, the battery holder 20's elasticity improves impact resistance and vibration resistance. Furthermore, portions of the positive terminal 12 and negative terminal 13 of the battery 11 are covered by extension portions 22. Specifically, the vicinity of the outer periphery of the circular positive terminal 12 and the vicinity of the outer periphery of the circular negative terminal 13 are covered by extension portions 22 when viewed from the ±Y direction. Therefore, as shown in Fig. 3 , movement of the battery 11 in the ±Y direction within the housing portion 21 can be restricted by extension portions 22. Therefore, even if vibration or impact is applied to the battery module 10, the batteries can remain housed within the battery housing portion.

[0024] The battery holder 20 of the present disclosure may be in contact with the battery 11. When the battery holder 20 is in contact with the battery 11, the gap between the battery holder 20 and the battery 11 is reduced, and movement of the battery 11 within the housing portion 21 can be further reduced. In other words, the battery can be properly held by the battery holder. In a preferred contact mode between the battery holder 20 and the battery 11, the battery holder 20 may be in contact while applying a pressing force toward the battery 11. For example, the pressing force may be applied in the ±X direction or ±Z direction. The extension portion 22 may also apply a pressing force in the ±Y direction. This type of contact mode can more suitably improve waterproofing.

[0025] In a preferred embodiment of the battery holder 20, the diameter D1 of the opening 23 when the battery 11 is housed in the housing portion 21 may be smaller than the diameter D2 of the battery 11 and equal to or greater than the diameter D3 of the positive electrode surface 12a of the battery 11 (see, for example, FIG. 3 ). By making the diameter D1 of the opening 23 smaller than the diameter D2 of the battery 11, the extension portion 22 can appropriately restrict movement of the battery 11 in the axial AX direction (movement in the ±Y directions in FIG. 3 ). Furthermore, by making the diameter D1 of the opening 23 equal to or greater than the diameter D3 of the positive electrode surface 12a of the battery 11, it is possible to prevent the opening from interfering with the electrical connection between the positive electrode surface and the tab.

[0026] The battery holder 20 of the present disclosure may be molded by force-removal of a mold. Force-removal molding is described below with reference to FIGS. 4( a) to 4(c). First, a pair of molds M1 and M2 for producing the molded product are clamped together, and the cavity CA of the molds M1 and M2 is filled with molding material (see FIG. 4(a)). After the molding material solidifies, the molds M1 and M2 are opened and released (see FIG. 4(b)). At this time, the undercut corresponding to the extension portion 22 is elastic and therefore elastically deforms as the molds M1 and M2 are forcefully released. In the example shown in FIG. 4(b), the undercut corresponding to the extension portion 22 elastically deforms in the direction of mold opening. After that, when the molds M1 and M2 are completely released, the undercut that elastically deformed as a result of the release elastically returns to its original shape, forming the extension portion 22 (see FIG. 4(c)). The molded product is then removed from the molds M1 and M2, thereby forming the battery holder 20, which is an integrally molded product made of elastic material.

[0027] In this way, the battery holder 20 of the present disclosure is formed by forcibly removing the dies M1 and M2, and at least one of the extensions 22 provided on both ends of the housing portion 21 is undercut, so that it can elastically deform during forcible removal from the die. Therefore, the desired extension 22 can be formed by forcibly releasing the die. Because the extension 22 can be made elastically deformable in this way, when inserting the battery 11 into the battery holder 20 during the manufacture of the battery module of the present disclosure, the elastic deformation of the extension 22 can further improve battery insertion.

[0028] Whether the extension 22 is an undercut can be determined by whether the extension 22 is scraped when the die is forcibly removed. In addition, if the extension 22 has a relatively high hardness, a cloudy white discoloration can be observed at the base of the extension 22 relative to the battery holder 20.

[0029] Considering that the battery holder 20 of the present disclosure is molded by forcing the molds M1 and M2 as described above, the specific material for the accommodating portion 21 and / or the extending portion 22 may be silicone rubber and / or elastomer. Thus, if the accommodating portion 21 and / or the extending portion 22 are made of silicone rubber and / or elastomer, they will elastically deform upon impact, thereby providing resistance to impact. Furthermore, if the extending portion 22 is made of silicone rubber and / or elastomer, the extending portion 22 will be more elastically deformable when inserting the battery 11 into the battery holder 20 during the manufacture of the battery module 10 of the present disclosure, thereby further improving battery insertion. Any elastic material may be selected for the accommodating portion 21 and / or the extending portion 22. Specifically, a material with an elongation [%] of 100 to 1000, a Young's modulus [GPa] of 0.01 to 10, and a Poisson's ratio of 0.3 to 0.5 may be used. Examples of the material include natural rubber, butyl rubber, fluororubber, ethylene propylene rubber, chloroprene rubber, and acrylonitrile rubber.

[0030] Tabs The battery module 10 of the present disclosure may further include tabs TB electrically connected to the batteries 11. In FIG. 2 , a pair of tabs TB may be provided to sandwich the battery 11 in the ±Y direction. The tabs TB may electrically connect the positive terminals 12 and / or negative terminals 13 of adjacent batteries 11. In FIG. 2 , the tabs TB may electrically connect the positive terminals 12 (or negative terminals 13) of adjacent batteries 11 in the ±Z direction, thereby electrically connecting them in parallel. In FIG. 2 , the tabs TB may electrically connect the positive terminals 12 and negative terminals 13 of adjacent batteries 11 in the ±X direction, thereby electrically connecting them in series.

[0031] As shown in FIG. 5A , the tab TB may be electrically connected to a protrusion 24 located around the opening 23 in a cross-sectional view perpendicular to the axis AX of the housing section 21 (e.g., a cross-sectional view taken along the ±X direction in FIG. 5A ). The protrusion 24 is part of the battery holder 20 and is easily elastically deformed. Therefore, when the battery 11 and the tab TB are electrically connected with the terminal surface of the battery 11 exposed through the opening 23, the protrusion 24 around the opening 23 elastically deforms, enhancing the airtightness between the tab TB and the battery holder 20. This enhances the airtightness of the housing section 21 and improves the waterproofness of the battery module. The protrusion 24 may have any shape as long as it is located around the opening 23. For example, it may be circular, elliptical, rectangular, or polygonal when viewed along the Y direction. Furthermore, as shown in FIG. 5C , the contact surface with the tab TB may be chamfered when viewed along the X direction. The height h of the protrusion 24 (see FIG. 5B ) may be approximately 10% to 100% of the thickness of the extension 22 to enhance sealing. Note that, as used herein, the "height of the protrusion 24" refers to the length of the protrusion 24 protruding from the extension 22 along the Y direction, as shown in FIG. 5B . The width w of the protrusion 24 is set to a value that allows the protrusion 24 to easily deform elastically when contacting the tab TB. Note that, as used herein, the "width w of the protrusion 24" refers to the length of the protrusion 24 along the Z direction, as shown in FIG. 5B . The tip shape of the protrusion 24 may be flat, curved, or triangular. Setting the height h, width w, and tip shape of the protrusion 24 in this manner can favorably enhance sealing between the tab and the battery holder. Furthermore, multiple protrusions 24 may be provided adjacent to each other in the Z direction, as shown in FIG. 5D . In the example shown in Fig. 5D, the heights h of the two protrusions 24 are the same, and the widths w1 and w2 of the protrusions 24 are longer on the side closer to the opening 23. Note that the protrusions 24 are not limited to the example shown in Fig. 5D, and for example, the heights h, widths w, and tip shapes of the two protrusions 24 may be the same or different.

[0032] -Control Board- The battery module 10 of the present disclosure may further include a control board SB that controls the supply of power to the batteries 11. In the example shown in Figure 2, the control board SB may be disposed on the outer surface of the battery holder 20. The control board SB may receive power from the batteries 11 via tabs TB, and may control the power output from the batteries 11 via tabs TB.

[0033] As described above, the battery module 10 of the present disclosure and the battery pack 1 including the battery module 10 are highly waterproof, and can maintain the battery storage within the battery storage section even when vibrations or impacts are applied.

[0034] [Modifications of Battery Module] Next, modifications 1 to 4 of the battery module 10 of the present disclosure will be described with reference to FIGS. 6A to 9B. FIGS. 6A to 8 are schematic cross-sectional views of modifications of the battery module 10 of the present disclosure, FIG. 9A is a schematic enlarged cross-sectional view of another modification of the battery module of the present disclosure, and FIG. 9B is a schematic enlarged cross-sectional view of another modification of the battery module of the present disclosure in which tabs are provided. Note that, in describing the battery modules of modifications 1 to 4, explanations of points common to the description in the above [Battery Module] section will be omitted as appropriate. In other words, the following description will focus on points that are different from the description in the above [Battery Module] section.

[0035] 6A , in Modification 1, at least one of the extensions 22 provided at both ends of the housing section 21 may be provided with a taper 22a that tapers toward the axis AX of the battery 11. If the extensions 22 are provided with a taper 22a that tapers toward the edge, the battery 11 can be inserted along the taper 22a when inserting the battery 11 into the battery holder 20, and the taper 22a facilitates elastic deformation of the extensions 22, further improving the ease of insertion of the battery 11. The taper 22a may be a curved surface from the perspective of ease of battery 11 insertion.

[0036] In a more preferred embodiment of the taper 22a, the taper 22a may have a slope on the outer surface side of the extension portion 22. Specifically, in the embodiment shown in Fig. 6A, the taper 22a on the positive electrode terminal 12 side may be provided on the +Y direction side of the extension portion 22, and the taper 22a on the negative electrode terminal 13 side may be provided on the -Y direction side of the extension portion 22. When the extension portion 22 is provided with a tapered taper 22a in this manner, the battery can be easily inserted along the taper, and the taper makes the extension portion more susceptible to elastic deformation, thereby further improving the ease of battery insertion.

[0037] The thickness T1 of the extension portion 22 on the opening 23 side due to the provision of the taper 22a may be approximately 10% to 50% of the maximum thickness T2 of the extension portion 22. In Modification 1, the "maximum thickness T2 of the extension portion 22" refers to the length T2 from the starting point of the imaginary line V to the intersection of the imaginary line V and the edge of the extension portion 22, based on an imaginary line V extending along the housing surface of the housing portion 21 (the surface facing the cylindrical surface of the cylindrical battery 11) when the battery module 10 is viewed in cross section along the X direction as shown in FIG. 6B . Such a taper 22a can further improve battery insertion.

[0038] 7A , in Modification 2 of the battery module 10, at least one of the extension portions 22 provided at both ends of the housing portion 21 may have a thin-walled portion 22b, which is a reduced thickness of the extension portion 22, on a surface of the extension portion 22 facing the battery 11 when viewed in a cross section perpendicular to the axis AX direction of the housing portion 21 (for example, a cross section viewed in the ±X directions in FIG. 7A ), on a position opposite to the direction toward the axis AX of the battery 11. More specifically, in FIG. 7A , the thickness of the extension portion 22 is notched at a position on the −Y direction side of the extension portion 22 and opposite to the direction toward the axis AX of the battery 11 (the −Z direction side in the case of the upper extension portion 22 in FIG. 7A , and the +Z direction side in the case of the lower extension portion 22), thereby reducing the thickness of the extension portion 22 to form the thin-walled portion 22b. The provision of the thin-walled portion 22b in this manner facilitates elastic deformation of the extending portion 22 starting from the thin-walled portion 22b, thereby further improving the ease of insertion of the battery 11. The minimum thickness T3 of the thin-walled portion 22b (see FIG. 7B ) may be approximately 50% of the maximum thickness T4 of the extending portion 22. In Modification 2, the "minimum thickness T3 of the thin-walled portion" refers to the length T3 from the starting point of the imaginary line V extending along the housing surface of the housing portion 21 (the surface facing the cylindrical surface 11a of the cylindrical battery 11) to the intersection of the imaginary line V and the edge of the extending portion 22 when the battery module 10 is viewed in cross section along the X direction as shown in FIG. 7B . Also, in Modification 2, the "maximum thickness of the extending portion 22" refers to the maximum length T3 of the extending portion 22 in the Y direction in the region closer to the opening 23 than the imaginary line V. Furthermore, from the viewpoint of the strength of the thin-walled portion 22b, the thin-walled portion 22b may have a thickness of approximately 90% of the maximum thickness of the extending portion 22. In other words, the thin-walled portion 22b may have a thickness of 50% to 90% of the maximum thickness of the extending portion 22. With this thickness, the strength of the thin-walled portion 22b is maintained, and the extending portion 22 can be elastically deformed appropriately when the battery 11 is inserted into the battery holder 20.

[0039] In a more preferred embodiment of the thin-walled portion 22b, the thin-walled portion 22b may have a slope on the housing portion 21 side. Specifically, in the embodiment shown in Fig. 7B, the thin-walled portion 22b on the positive terminal 12 side may have a slope on the -Y direction side of the extending portion 22, and the thin-walled portion 22b on the negative terminal 13 side may have a slope on the -Y direction side of the extending portion 22. By providing the thin-walled portion 22b with a slope on the housing portion 21 side in this manner, the extending portion 22 can easily deform toward the inside of the housing portion 21 when the battery 11 is inserted into the battery holder 20, further improving battery insertion.

[0040] -Modification 3- In Modification 3 of the battery module 10, as shown in FIG. 8 , in at least one of the extension portions 22 provided at both ends of the housing portion 21, the thickness T5 of the extension portion 22 may be thinner than the thickness T6 of the housing portion 21 at a position facing the battery 11. By specifying the thickness of the extension portion 22 in this manner, the extension portion 22 becomes more easily deformable, further improving the ease of battery insertion. As an example of the thickness of the extension portion 22, the thickness T5 of the extension portion 22 may be approximately 50% of the thickness T6 of the housing portion 21 at a position facing the battery 11. Furthermore, from the standpoint of the strength of the extension portion 22, the thickness T5 of the extension portion 22 may be approximately 90% of the thickness T6 of the housing portion 21 at a position facing the battery 11. In other words, the thickness T5 of the extension portion 22 may be 50% to 90% of the thickness T6 of the housing portion 21 at a position facing the battery 11. This thickness allows the extension 22 to be elastically deformed appropriately when the battery 11 is inserted into the battery holder 20 while maintaining the strength of the thin portion 22 b.

[0041] Variation 4: In Variation 4 of the battery module 10, as shown in Figures 9A and 9B, at least one of the extensions 22 provided at both ends of the housing portion 21 may be curved in an arc toward the axis AX while bulging in the +Y direction from the end of the battery holder 20. By curving the extension 22 in an arc in this manner, the length of the arc of the extension 22 can be made approximately the same as the length of the extension 22 of the battery module shown in Figure 3, while achieving an opening diameter D1' wider than the opening diameter D1 shown in Figure 3. Increasing the opening diameter D1' as in Variation 4 makes it easier to forcibly remove the mold during molding of the battery holder 20. It also makes it easier to insert the battery 11 into the battery holder 20.

[0042] Furthermore, thickness T7 of extension portion 22 may be thinner than thickness T6 of storage portion 21 (see FIG. 9A ). This configuration makes it easier to elastically deform extension portion 22, facilitating the removal of the mold or the insertion of the battery.

[0043] Furthermore, when a tab TB is provided on the battery module 10 of Variation 4 as shown in FIG. 9B , the arc-shaped extension 22 is elastically deformed by being pressed by the tab TB, thereby improving the adhesion between the tab TB and the extension 22. This improves the waterproofness and / or explosion resistance of the battery module 10. Note that the "improved explosion resistance" in Variation 4 refers to the fact that the close adhesion between the tab TB and the battery holder 20 prevents abnormal gas from being released from a battery with an abnormality from passing between the tab TB corresponding to the battery 11 adjacent in the Y direction or X direction (see FIG. 2 ) and the extension 22 of the battery holder 20 and entering the battery holder 20.

[0044] As a more specific example of Modification 4, a space S may be provided between the surface TB1 of the tab TB facing the battery 11 and the surface 121 of the positive terminal 12 (or negative terminal 13) (see FIG. 9B ). When the space S is provided in this manner, if an external impact is applied in the axial direction of the battery 11 (the ±Y direction in FIG. 9B ), the space S functions to allow the extension portion 22 to elastically deform. This elastic deformation of the extension portion 22 absorbs the external impact. This improves the impact resistance and / or vibration resistance of the battery module 10.

[0045] The embodiments disclosed herein are illustrative in all respects and are not intended to be limiting. Therefore, the technical scope of the present disclosure should not be interpreted solely by the above-described embodiments, but should be defined by the claims. The technical scope of the present disclosure also includes all modifications within the meaning and scope of the claims. For example, in the embodiment shown in FIG. 5A , the extension 22 on the positive terminal 12 side may be configured differently from the extension 22 on the negative terminal 13 side. As an example, the extension 22 on the positive terminal 12 side may be configured as shown in FIG. 3 , and the extension 22 on the negative terminal 13 side may be configured as shown in FIG. 5A .

[0046] The battery module and battery pack of the present disclosure include the following aspects: <1> A battery module comprising: a cylindrical battery; and a battery holder, an integral elastic member, for housing and holding the battery, wherein the battery holder has a housing portion for housing the battery, and both ends of the housing portion have extension portions extending toward the axis of the battery and openings surrounded by the extension portions. <2> The battery module described in <1>, wherein the battery has a positive electrode surface on one side in the axial direction, and the diameter of the opening when the battery is housed in the housing portion is smaller than the diameter of the battery and equal to or greater than the diameter of the positive electrode surface. <3> The battery module described in <1> or <2>, wherein the extension portion has a taper that narrows toward the axis of the battery. <4> The battery module described in <3>, wherein the taper has a slope on the outer surface side of the extension portion. <5> The battery module according to any one of <1> to <4>, wherein at least one of the extensions provided at both ends of the housing portion has a thin-walled portion in which the thickness of the extension is reduced on the side facing the battery when viewed in a cross section perpendicular to the axial direction of the housing portion. <6> The battery module according to <5>, wherein the thin-walled portion has a slope facing the housing portion. <7> The battery module according to any one of <1> to <6>, wherein at least one of the extensions provided at both ends of the housing portion has a thickness thinner than the thickness of the housing portion at a position facing the battery when viewed in a cross section perpendicular to the axial direction of the housing portion. <8> The battery module according to any one of <1> to <7>, further comprising a tab electrically connected to the battery, wherein a protrusion is provided around the opening when viewed in a cross section perpendicular to the axial direction of the housing portion. <9> The battery module according to any one of <1> to <8>, wherein the extension of at least one of the extensions provided at both ends of the housing portion is an undercut. <10> A battery module described in any one of <1> to <9>, wherein at least one of the extension portions provided at both ends of the storage portion has an arc-shaped curved shape from the end of the battery holder.<11> The battery module according to any one of <1> to <10>, wherein the housing portion and / or the extension portion are made of silicone rubber and / or elastomer. <12> The battery module according to any one of <1> to <11>, wherein the battery holder contacts the battery. <13> A battery pack including the battery module according to any one of <1> to <12>.

[0047] The present disclosure can be suitably used as a battery module and a battery pack that are highly waterproof and can maintain the storage of batteries in the storage section even when subjected to vibration or impact.

[0048] REFERENCE SIGNS LIST 1 Battery pack 10 Battery module 11 Battery 12 Positive electrode terminal 12a Positive electrode surface 13 Negative electrode terminal 20 Battery holder 21 Storage section 22 Extension section 22a Tapered section 22b Thin section 23 Opening 24 Convex section D1, D1' Diameter of opening D2 Diameter of battery D3 Diameter of positive electrode surface T1 Thickness of extension section T2 Thickness of outer peripheral surface of storage section TB Tab SB Control board CS Case CS1 First case CS2 Second case CN Connector M1, M2 Mold CA Cavity

Claims

1. A cylindrical battery, A single piece made of an elastic material, comprising a battery holder for housing and holding the battery, The battery holder has a housing portion for housing the battery, A battery module having an extended portion extending toward the axis of the battery and an opening surrounded by the extended portions at both ends of the housing portion.

2. The aforementioned battery has a positive electrode surface on one side in the axial direction, The battery module according to claim 1, wherein the diameter of the opening when the battery is housed in the housing is smaller than the diameter of the battery and greater than or equal to the diameter of the positive electrode surface.

3. The battery module according to claim 1, wherein at least one of the extended portions provided at both ends of the housing portion is provided with a taper that narrows toward the axis of the battery.

4. The battery module according to claim 3, wherein the taper has a slope on the outer surface side of the extended portion.

5. The battery module according to claim 1, wherein at least one of the extended portions provided at both ends of the housing portion has a thin-walled portion in which the thickness of the extended portion on the side facing the battery is reduced when viewed in a cross-sectional view perpendicular to the axial direction of the housing portion.

6. The battery module according to claim 5, wherein the thin-walled portion has a slope on the side of the housing portion.

7. The battery module according to claim 1, wherein in at least one of the extended portions provided at both ends of the housing portion, when viewed in a cross-sectional view perpendicular to the axial direction of the housing portion, the thickness of the extended portion is thinner than the thickness of the housing portion at the position facing the battery.

8. The battery further comprises a tab that is electrically connected to the battery, The battery module according to claim 1, wherein a protrusion is provided around the opening in an axial cross-sectional view of the housing portion.

9. The battery module according to claim 1, wherein at least one of the extended portions provided at both ends of the housing portion is an undercut.

10. The battery module according to claim 1, wherein at least one of the extended portions provided at both ends of the housing portion is curved in an arc shape from the end of the battery holder.

11. The battery module according to claim 1, wherein the housing portion and / or the extending portion are made of silicone rubber and / or elastomer.

12. The battery module according to claim 1, wherein the battery holder is in contact with the battery.

13. A battery pack comprising the battery module described in claim 1.