Battery pack

Abstract

The present invention increases impact strength by allowing an outer case to absorb an impact on a core pack containing a plurality of batteries.　This battery pack comprises a core pack (2) containing a plurality of batteries, and an outer case (1) containing the core pack (2). The outer case (1) has a box shape formed by connecting an outer peripheral wall (4) to an outer periphery of a pair of surface plates (3). The outer peripheral wall (4) provided at an external corner (3a) of the surface plates (3) includes an impact absorbing gap (7) formed by separating, at a predetermined interval, an impact absorbing wall (5) on an outer surface and a main body wall (6) disposed inside the impact absorbing wall (5). The impact absorbing gap (7) is open on the side of the surface plates (3).

Description

[Technical Field]

[0001] The present invention relates to a battery pack in which a plurality of batteries are housed in an exterior case, and particularly to a battery pack having excellent impact resistance. [Background technology]

[0002] Battery packs require impact resistance. In particular, battery packs that contain a large number of batteries and are heavy require impact resistance so that they will not break when subjected to a large impact such as being dropped. Battery packs that contain a large number of batteries have a large charge / discharge capacity, are heavy, and are expensive, so if they are damaged by being dropped or otherwise damaged and become unusable, the economic loss is significant. Furthermore, expensive battery packs with a large charge / discharge capacity are heavy and easily damaged by a large impact when dropped, so it is extremely important to have strong impact resistance. To achieve this, battery packs have been developed that have shock-absorbing gaps inside the case (see Patent Documents 1 and 2). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2007-273180 [Patent Document 2] Japanese Patent Application Laid-Open No. 2011-192592 Summary of the Invention

[0004] The battery pack in Patent Document 1 has a shock absorbing gap between the inner case and the outer case, and an elastic spring such as a metal plate is placed in this gap. This battery pack has a unique structure between the inner case and the outer case, and an elastic spring processed into a specific shape is placed in the shock absorbing gap, which results in high parts costs, and furthermore, the elastic spring is placed in a fixed position in the case, which results in labor-intensive assembly and high assembly costs. In addition, the battery pack in Patent Document 2 has an inner wall provided inside the shock-absorbing wall provided in the case, a battery core pack is placed inside this inner wall, and the inner wall is formed into a unique shape to provide a shock-absorbing gap between the inner wall and the battery core pack. With a battery pack of this structure, the battery core pack is subjected to localized shocks, making it difficult to protect the entire heavy core pack from strong shocks. [Problem to be solved by the invention]

[0005] The present invention was developed with the aim of further resolving the above-mentioned drawbacks, and an important object of the present invention is to provide a battery pack that can increase impact resistance by using an outer case to absorb impacts acting on the core pack of the built-in battery. [Means for solving the problem]

[0006] A battery pack according to one embodiment of the present invention comprises a core pack for housing a plurality of batteries and an exterior case for housing the core pack. The exterior case is box-shaped and has an outer wall connected to the outer edges of a pair of surface plates. The outer wall is provided at the corners of the surface plates and has an impact absorbing gap separating an impact absorbing wall on the outer surface from a main body wall disposed inside the impact absorbing wall by a predetermined distance. A pair of both sides It opens on the surface plate side. The intermediate parts of the outer peripheral wall located between the projecting corner parts do not protrude outward beyond the tip parts of the shock absorbing walls of the projecting corner parts, and the tip parts in the height direction of the shock absorbing walls extend to the position of the surface plate, so that the surface plate does not receive the impact before the tip edge of the shock absorbing wall. [Effects of the Invention]

[0007] The battery pack described above achieves high impact resistance by using the exterior case itself to absorb impacts acting on the core pack that houses multiple batteries. In particular, it effectively absorbs impacts received at the corners when dropped, achieving high impact resistance. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a plan view of a battery pack according to a first embodiment of the present invention. [Figure 2] FIG. 10 is a plan view of a battery pack according to a second embodiment of the present invention. [Figure 3] FIG. 10 is a front view of a battery pack according to a third embodiment of the present invention. [Figure 4] 2 is a cross-sectional perspective view showing an exterior case of the battery pack shown in FIG. 1. FIG. [Figure 5] 1. FIG. 4 is a cross-sectional perspective view showing another example of the exterior case of the battery pack shown in FIG. [Figure 6] FIG. 10 is a partially enlarged perspective view of a battery pack according to a fourth embodiment of the present invention. [Figure 7] FIG. 7 is a cross-sectional perspective view of the battery pack shown in FIG. 6 taken along line VII-VII. [Figure 8] FIG. 8 is a cross-sectional perspective view of the battery pack shown in FIG. 6 taken along line VIII-VIII. [Figure 9] FIG. 7 is a cross-sectional perspective view of the battery pack shown in FIG. 6 taken along line IX-IX. [Figure 10] FIG. 7 is a perspective cross-sectional view of the battery pack shown in FIG. 6 taken along line XX. DETAILED DESCRIPTION OF THE INVENTION

[0009] A battery pack according to one embodiment of the present invention comprises a core pack for housing a plurality of batteries and an exterior case for housing the core pack. The exterior case is box-shaped and has an outer wall connected to the outer edges of a pair of surface plates. The outer wall, which is provided at the corners of the surface plates, has an impact absorbing gap that separates, by a predetermined distance, an impact absorbing wall on the outer surface from a main body wall located inside the impact absorbing wall, and the impact absorbing gap is open toward the surface plates.

[0010] The above-described battery packs achieve high impact resistance by absorbing impacts acting on the built-in core pack with the exterior case itself. This is because the battery packs have shock-absorbing gaps separating the main body wall and the shock-absorbing wall at the outer peripheral wall of the projecting corner, which is subject to shock when dropped or otherwise impacted. The cross-sectional perspective view of Figure 4 shows how the outer peripheral wall of the projecting corner deforms upon impact. As shown in this figure, the outer peripheral wall 4 of the projecting corner 3a is provided with a shock-absorbing wall 5 on the outside of the main body wall 6 via a shock-absorbing gap 7, and the shock-absorbing gap 7 opens toward the surface plate 3. As shown by arrow A in the figure, the shock-absorbing wall 5 deforms and absorbs the impact received by the outer peripheral wall 4 of the projecting corner 3a, improving the impact resistance of the projecting corner 3a. Furthermore, because the shock-absorbing wall deforms to absorb the impact, the shock-absorbing effect of the shock-absorbing wall also protects the built-in core pack from impact.

[0011] When a battery pack is dropped, the probability of it coming into surface contact with a horizontal or vertical surface and receiving an impact is extremely low. Since a falling battery pack almost always falls at an angle, when it hits the ground, it will strike one of the side edges of the outer peripheral wall, which is a corner of the outer peripheral wall, and receive the impact. In these battery packs, the shock absorbing gaps are open on the surface plate side, so the tips of the shock absorbing walls are positioned on the side edges of the outer peripheral wall. The tip edges of the shock absorbing walls are easily deformed. Therefore, the shock received at the tip edges of the shock absorbing walls located on the side edges of the outer peripheral wall is efficiently absorbed by the shock absorbing walls, improving the impact resistance of the exterior case and further reducing the impact on the built-in battery pack through the cushioning effect of the shock absorbing walls.

[0012] In a battery pack according to another embodiment of the present invention, the opening width (W1) of the shock absorbing gap is set to 2 mm or more.

[0013] In another embodiment of the battery pack of the present invention, the outer case comprises a box-shaped first case formed by integrally molding a surface plate and an outer peripheral wall around the surface plate, and a second case that closes the opening of the first case, and the first and second cases have connecting flanges that connect the main body wall and the shock absorbing wall, and the first and second cases are connected via the connecting flanges.

[0014] In a battery pack according to another embodiment of the present invention, the outer peripheral wall has connecting ribs that locally connect the shock absorbing wall and the main body wall.

[0015] In a battery pack according to another embodiment of the present invention, the shock absorbing wall has a longitudinal rib that protrudes from the outer surface and is integrally formed along the leading edge.

[0016] The battery pack described above has the advantage that the vertical ribs can diffuse the impact that acts locally on the leading edge of the impact absorbing wall, thereby increasing the impact resistance strength of the impact absorbing wall.

[0017] In another embodiment of the battery pack of the present invention, the corners of the surface plate have curved portions that are curved at a predetermined radius of curvature, and the openings of the shock absorbing gaps are formed by the surface plate. of The slit is curved along the curved portion of the corner.

[0018] In a battery pack according to another embodiment of the present invention, the exterior case has a grip, and the exterior case has shock absorbing walls at the corners on both sides of the outer peripheral wall located opposite the grip.

[0019] The above battery packs have the advantage that even if they are accidentally dropped while being carried by the grip, the shock-absorbing wall at the bottom opposite the grip will absorb the impact and prevent damage.

[0020] In a battery pack according to another embodiment of the present invention, the surface of the tip edge of the shock absorbing wall is a protruding portion that protrudes further than the center of the outer peripheral wall.

[0021] The above battery pack has a high impact resistance because the shock absorbing walls effectively absorb the impact no matter what position the battery pack is dropped in. This is because the protruding portions at the leading edges of the shock absorbing walls absorb the impact when hitting the ground or the like no matter what position the battery pack is dropped in.

[0022] In a battery pack according to another embodiment of the present invention, the outer surface of the shock absorbing wall is an inclined surface that protrudes from the center toward the leading edge.

[0023] In a battery pack according to another embodiment of the present invention, the overall shape of the surface plate is polygonal, and the outer wall connected to the linear region of the polygonal surface plate has protrusions at both ends of the linear region.

[0024] The above battery pack has strong impact resistance because the shock absorbing walls effectively absorb the impact no matter what position the battery pack is dropped in. This is because, no matter what position the battery pack is dropped in, the protrusions on both ends of the straight region locally impact the ground or the like, and the outer peripheral walls of the corners on both ends of the straight region absorb the impact.

[0025] The present invention will be described in detail below with reference to the drawings. In the following description, terms indicating specific directions or positions (e.g., "upper," "lower," and other terms including these terms) will be used as necessary. However, the use of these terms is intended to facilitate understanding of the invention with reference to the drawings, and the meaning of these terms does not limit the technical scope of the present invention. Furthermore, parts that appear with the same reference numerals in multiple drawings indicate the same or equivalent parts or components. Furthermore, the embodiments shown below are specific examples of the technical concept of the present invention and are not intended to limit the present invention thereto. Furthermore, unless otherwise specified, the dimensions, materials, shapes, relative positions, etc. of the components described below are intended as examples and are not intended to limit the scope of the present invention thereto. Furthermore, the content described in one embodiment or example can also be applied to other embodiments or examples. Furthermore, the sizes and positional relationships of components shown in the drawings may be exaggerated for clarity of explanation.

[0026] (Battery packs 100, 200, 300) Battery packs 100, 200, and 300 shown in the plan views of Figures 1 to 3 and the cross-sectional views of Figures 4 and 5 each have a core pack 2 containing multiple batteries disposed inside an exterior case 1. Note that Figure 4 shows a perspective cross-sectional view of the battery pack 100 in Figure 1 taken along line IV-IV, and Figure 5 shows a perspective cross-sectional view of another example corresponding to the cross-section of the battery pack 100 in Figure 1 taken along line IV-IV. The exterior case 1 is box-shaped, with an outer peripheral wall 4 connected to the periphery of a surface plate 3. The outer peripheral wall 4, which is provided at a corner 3a of the surface plate 3, separates an impact absorbing wall 5 on the outer surface from a main body wall 6 located inside the impact absorbing wall 5 by a predetermined distance, with the impact absorbing gap 7 opening toward the surface plate 3. The impact absorbing wall 5 deforms when subjected to an impact to absorb the impact.

[0027] 1 has shock absorbing walls 5 on the outer peripheral wall 4 around the entire periphery of the surface plate 3, while battery pack 200 in FIG. 2 has shock absorbing walls 5 on the outer peripheral wall 4 at the four corners 3a of the surface plate 3. Battery pack 300 in FIG. 3 has shock absorbing walls 5 on the corners 3a at both ends of the outer peripheral wall 4 on the side opposite the grip 15. As shown in these figures, battery packs 100, 200, and 300 have shock absorbing walls 5 on the outer peripheral wall 4 at the corners 3a of the surface plate 3, but shock absorbing walls 5 are not necessarily provided on all corners 3a. Instead, shock absorbing walls 5 are provided at least on the corners 3a that are subject to shock from being dropped, etc., to improve shock resistance.

[0028] (Core Pack 2) The battery pack 100 shown in Figures 4 and 5 has a core pack 2 containing multiple batteries arranged inside an exterior case 1. Although not shown, the core pack 2 has multiple batteries arranged in fixed positions using a battery holder, with the batteries connected in series or parallel. Furthermore, the core pack 2 has a circuit board mounted on the battery holder that mounts a control circuit and protection circuit that control the charging and discharging of the batteries. The core pack 2 is arranged in a fixed position inside the exterior case 1 without moving.

[0029] (Outer case 1) The exterior case 1 is box-shaped, with an outer wall 4 connected to the outer edges of polygonal surface plates 3 on both sides, and houses a core pack 2 inside. In the battery packs 100, 200, and 300 shown in Figures 1 to 3, the surface plate 3 of the exterior case 1 is rectangular, and the outer wall 4 is provided around the surface plate 3, forming a rectangular box shape with the surface plate 3 and outer wall 4. The exterior case 1 shown in Figures 4 and 5 has a first case 1X and a second case 1Y, which are separately molded from plastic, connected at their open ends, and the core pack 2 is placed in a fixed position inside. The exterior case 1 connects the first case 1X and the second case 1Y via connecting flanges 8 provided at the open ends of the outer wall 4, and the core pack 2 is placed inside. In the outer case 1 of Fig. 4, the first case 1X and the second case 1Y are connected by screwing set screws 19 at predetermined intervals into the connecting flanges 8 of the first case 1X and the second case 1Y. In the outer case 1 of Fig. 5, the first case 1X and the second case 1Y are connected by welding or gluing the connecting flanges 8. In the outer case 1 described above, the connecting flanges 8 of the first case 1X and the second case 1Y are connected by set screws 19, or by welding or gluing, but the present invention does not specify the structure for connecting the first case and the second case, and the first case and the second case can also be connected by various other connecting structures, such as a fitting structure or a locking structure.

[0030] The outer case 1 in Figures 1 and 2 has a rectangular surface plate 3, but the surface plate 3 does not necessarily have to be rectangular. For example, as shown in the front view of Figure 3, the upper surface of the outer case 1 can be arched, with grips 15 provided on the upper surface, and the outer walls 4 on both sides and the bottom surface connected at right angles to both sides of the bottom surface.

[0031] The exterior case 1 is provided with shock absorbing walls 5 on the outer peripheral wall 4 at the corners 3a of the surface plate 3 to absorb the shock received in a collision. The outer peripheral wall 4 shown in the cross-sectional views of Figures 4 and 5 has a shock absorbing gap 7 between the shock absorbing wall 5 located on the outer surface and the main body wall 6 located inside the shock absorbing wall 5, separating the shock absorbing wall 5 and the main body wall 6 by a predetermined distance. The shock absorbing gap 7 is open on the surface plate 3 side, giving the shock absorbing wall 5 a shape that is easily deformed by a shock.

[0032] The battery packs 100 and 200 can have increased impact resistance by increasing the strength of the protruding corners 3a of the surface plate 3. The exterior case 1 in Figures 1 and 2 has shock absorbing walls 5 on the outer peripheral wall 4 of the protruding corners 3a of the surface plate 3 to efficiently absorb impacts such as those caused by a fall. The exterior case 1 in Figures 1 and 2 has the protruding corners 3a of the surface plate 3 as curved parts that curve with a predetermined radius of curvature, and has curved shock absorbing walls 5 that follow the curved protruding corners 3a.

[0033] The exterior case 1 in Fig. 2 has reinforcing ribs 13 provided at predetermined intervals on the surface of the outer peripheral wall 4 of the straight region 3b of the surface plate 3. The reinforcing ribs 13 are plate-shaped and extend in the width direction of the outer peripheral wall 4, and are formed integrally with the outer peripheral wall 4. In this exterior case 1, impacts at the projected corners 3a are absorbed by the shock absorbing walls 5, and impacts at the straight region 3b are reinforced by the reinforcing ribs 13 on the surface.

[0034] The shock absorbing wall 5 shown in the cross-sectional views of Figures 4 and 5 connects the base of the shock absorbing wall 5 and the main body wall 6 to a connecting flange 8 that connects the first case 1X and the second case 1Y. The opening 7a of the shock absorbing gap 7 has an opening width (W1) of, for example, 2 mm or more, preferably 3 mm or more, and more preferably 5 mm or more, so that the shock absorbing wall 5 can deform in the direction shown by arrow A in Figures 4 and 5 when it receives an impact.

[0035] The shock absorbing gap 7 is formed in a tapered shape with an inner width that increases from the connecting flange 8 toward the opening 7a, which increases the amount of deformation of the tip of the shock absorbing wall 5 due to an impact. Furthermore, the shock absorbing wall 5 has an inner width (W2) of the shock absorbing gap 7 that increases toward the opening 7a, and is gradually thinner from the connecting flange 8 toward the opening 7a. This shock absorbing wall 5 has the advantage that the thin tip edge is easily deformed and can efficiently absorb shock.

[0036] Furthermore, as shown in Figures 4 and 5, the shock absorbing wall 5 can also be structured so that it is connected to the main wall 6 by connecting ribs 9 provided in the shock absorbing gap 7. This shock absorbing wall 5 can have increased impact resistance by being reinforced by the connecting ribs 9. The connecting ribs 9 connecting both ends of the shock absorbing wall 5 to the main wall 6 reinforce the impact resistance by providing strength that allows the shock absorbing wall 5 to deform and absorb the impact without breaking when it is subjected to an impact. The exterior case 1 in Figures 4 and 5 has connecting ribs 9 provided at predetermined intervals in the shock absorbing gap 7 to locally reinforce the shock absorbing wall 5 and the main wall 6, but the number and positions at which the connecting ribs 9 connect the shock absorbing wall 5 and the main wall 6, as well as the strength and thickness at which the connecting ribs 9 deform upon impact, can be adjusted to deform the shock absorbing wall 5 and absorb the impact while also providing reinforcement.

[0037] The shock absorbing wall 5 shown in the cross-sectional views of FIGS. 4 and 5 has a protruding portion 5a at the surface of the open end that protrudes beyond the central portion 5c of the outer peripheral wall 4. In these figures, the outer peripheral wall 4 has a V-shaped cross section, and the outer surface of the shock absorbing wall 5 has an inclined surface 5b that protrudes from the region where the central portion 5c connects to the connecting flange 8 toward the leading edge, with the leading edge being the protruding portion 5a. This shock absorbing wall 5 has the advantage of being able to efficiently absorb shock, such as from a fall, by receiving it with the easily deformable protruding portion 5a. No matter what position the battery pack 100 is in when it falls onto a flat surface, the protruding leading edge of the shock absorbing wall 5 always hits the ground, etc., and efficiently absorbs the shock. Therefore, regardless of the position of the battery pack 100 when it falls, the shock absorbing wall 5 always effectively absorbs the shock, thereby improving the impact resistance of the outer case 1.

[0038] Furthermore, as shown by the dotted line in FIG. 4 , the shock absorbing wall 5 may be provided with a vertical rib 10 integrally formed along the leading edge thereof, so that the leading edge of the shock absorbing wall 5 protrudes more than the center. The shock absorbing wall 5 with the vertical rib 10 at its leading edge has the advantage of being able to enhance its impact resistance in all drop positions, without necessarily requiring the outer surface of the outer peripheral wall 4 to have a V-shaped cross section, as shown in FIG. 4 . Furthermore, as shown in FIG. 4 , a structure in which the outer surface of the outer peripheral wall 4 has a V-shaped cross section and the vertical rib 10 at the leading edge of the shock absorbing wall 5 increases the amount of protrusion of the leading edge of the shock absorbing wall 5, enhancing its impact resistance in all drop positions. Furthermore, the shock absorbing wall 5 with the vertical rib 10 at its leading edge also achieves the advantage of being able to enhance its impact resistance in all drop positions, even when the shock absorbing wall 5 is dropped from the battery pack 100 and receives a strong localized impact at the leading edge of the shock absorbing wall 5, by dispersing the impact to both sides with the vertical rib 10. Therefore, in the case 1 having the shock absorbing walls 5 in the shape shown by the dashed lines in Fig. 4, the shock absorbing walls 5 effectively absorb the shock no matter what position the battery pack 100 is dropped in, achieving high shock resistance. This is because the protruding portions 5a on the side edges on both sides of the outer peripheral wall 4 impact the ground or the like and absorb the shock no matter what position the battery pack 100 is dropped in.

[0039] (Battery pack 400) The battery pack 400 shown in the partially enlarged perspective view of Figure 6 illustrates an embodiment in which the exterior case 1 is made up of a first case 1X and a second case 1Y that are molded into different shapes. Figures 7 to 10 each show an enlarged cross-sectional perspective view of the battery pack shown in Figure 6. In the exterior case 1 in these figures, the first case 1X and the second case 1Y are molded from plastic into different shapes, and shock absorbing gaps 7 and shock absorbing walls 5 are provided at the protruding corners 3a of the outer peripheral wall 4.

[0040] Figure 7 is a perspective cross-sectional view taken along line VII-VII in Figure 6, showing the cross-sectional shape of the outer peripheral wall 4 of the projected corner portion 3a. The shock absorbing wall 5 in this figure connects the first shock absorbing wall 5X and the second shock absorbing wall 5Y with a vertical rib 10 located on the same plane as the surface plate 3, and an shock absorbing gap 7 is formed between the vertical rib 10 and the surface plate 3. The first shock absorbing wall 5X and the second shock absorbing wall 5Y are hollow on the inside, and a lower end opening 11 is connected to the connecting flange 8 of the second case 1Y. The first shock absorbing wall 5X is located inside the second shock absorbing wall 5Y, and its base is connected to the connecting flange 8 in an integral structure, providing an shock absorbing gap 7 between it and the main body wall 6. The second shock absorbing wall 5Y is not connected to the connecting flange 8, and when an impact is received in the direction indicated by arrow A in Figure 7, the shock absorbing wall 5, which is an integral structure of the first shock absorbing wall 5X and the second shock absorbing wall 5Y, deforms to absorb the impact.

[0041] 8 is a perspective cross-sectional view taken along line VIII-VIII in FIG. 6 and shows the connection portion of the connecting flange 8 at the projected corner 3a of the first case 1X and the second case 1Y. The first case 1X and the second case 1Y are connected to each other by set screws 19 via the connecting flanges 8 provided on each case. The shock absorbing wall 5 provided at the projected corner 3a is made up of the first shock absorbing wall 5X and the second shock absorbing wall 5Y, which are connected to each other as an integral structure via vertical ribs 10. The first shock absorbing wall 5X, which is located on the inside, is entirely connected to the connecting flange 8, and only the area of ​​the second shock absorbing wall 5Y that is connected to the second case 1Y is locally connected to the connecting flange 8 via set screws. Therefore, when the shock absorbing wall 5 is subjected to an impact, both the first shock absorbing wall 5X and the second shock absorbing wall 5Y elastically deform to absorb the impact, thereby achieving strength that can withstand strong impacts.

[0042] FIG. 9 is a perspective cross-sectional view taken along line IX-IX in FIG. 6 , showing the connection portion of the connecting flange 8 in the linear region 3b of the first case 1X and the second case 1Y. FIG. 9 shows the portion where the connecting flange 8 is connected by a set screw 19. The first case 1X and the second case 1Y shown in FIGS. 8 and 9 are locally provided with the connecting flange 8 in the portion connected by the set screw 19. In the region where the connecting flange 8 is provided, the first case 1X has a through hole in the vertical rib 10, and the connecting flange 8 is formed at the bottom of the through hole. The set screw 19, which is screwed from the connecting flange 8 of the first case 1X to the connecting flange 8 of the second case 1Y, connects the first case 1X and the second case 1Y with the connecting flange 8. As shown in FIG. 7, the hollow portion 12 between the first shock absorbing wall 5X and the second shock absorbing wall 5Y has an opening at the lower end in the area that is not connected by the set screw 19, and the lower end opening 11 is connected in a fitting structure to the connecting ridge 8a provided on the connecting flange 8 of the second case 1Y.

[0043] The shock absorbing wall 5 of the first case 1X shown in the cross-sectional perspective views of Figures 7 to 9 has a tapered shock absorbing gap 7 with an inner width (W2) that increases toward the opening 7a (upward in the figures), and the first shock absorbing wall 5X gradually becomes thinner toward the leading edge, making it easily deformable upon impact. This shock absorbing wall 5 has the advantage of being able to increase the amount of deformation in response to impact force and more effectively absorb impact. Furthermore, the shock absorbing wall 5 of Figures 7 and 8 has a protrusion 5a on the leading edge of the outer surface of the second shock absorbing wall 5Y, which forms the outer surface of the shock absorbing wall 5. This shock absorbing wall 5 has the advantage of being able to effectively deform and reliably absorb impact when the protrusion 5a impacts the ground or the like when dropped, thereby reliably absorbing impact.

[0044] In the first case 1X, the outer peripheral wall 4 connected to the linear region 3b of the surface plate 3 absorbs impact with a single impact absorbing wall 5, rather than two impact absorbing walls, as shown in FIG. 10 . The outer peripheral wall 4 of the linear region 3b is provided with an impact absorbing wall 5 that is located on the same plane as the second impact absorbing wall 5Y, and this impact absorbing wall 5 is connected to the outer surface of the main body wall 6 by a connecting rib 9. The impact absorbing wall 5 is connected to the main body wall 6 via multiple connecting ribs 9 arranged at predetermined intervals. Because the impact absorbing wall 5 of the linear region 3b is located on the same plane as the second impact absorbing wall 5Y, the opening width (W1) of the impact absorbing gap 7 between the linear region 3b and the main body wall 6 can be widened. Therefore, the impact absorbing wall 5 of the linear region 3b has enough strength to deform but not break upon impact, achieving a structure that can efficiently absorb impact.

[0045] 6 has shock absorbing gaps 7 and shock absorbing walls 5 provided around the entire periphery of the surface plate 3 of the first case 1X, thereby increasing the shock resistance strength all around. However, the outer case 1 can also be configured so that shock absorbing gaps 7 and shock absorbing walls 5 are provided only at the protruding corners 3a, rather than around the entire periphery, and no shock absorbing walls 5 are provided in the linear regions 3b of the outer case 1.

[0046] As shown in the cross-sectional perspective views of Figures 7 to 10, the second case 1Y has shock absorbing walls 5 formed from a single plate, and shock absorbing gaps 7 are provided between the shock absorbing walls 5 and the main wall 6. The shock absorbing walls 5 have longitudinal ribs 10 integrally formed along their leading edges. Furthermore, connecting ribs 9 extending in the width direction at predetermined intervals are integrally formed on the surface of the shock absorbing walls 5. The connecting ribs 9 are integrally formed with connecting flanges 8 and longitudinal ribs 10 at both ends, and with the side edges of the shock absorbing walls 5. The longitudinal ribs 10 are formed thicker than the connecting ribs 9 to distribute the shock acting on the leading edges of the shock absorbing walls 5 to both sides, preventing damage to the shock absorbing walls 5. The connecting ribs 9 reinforce the shock absorbing walls 5 and suppress deformation due to impact. Therefore, the thickness and height of the connecting ribs 9, the spacing between adjacent connecting ribs 9, and the thickness of the shock absorbing walls 5 can be adjusted to optimal values ​​for shock absorption by the shock absorbing walls 5. [Industrial Applicability]

[0047] The present invention is a battery pack in which a plurality of batteries are housed in an exterior case, and can be suitably used as a battery pack that has excellent impact resistance, particularly against a large impact such as being dropped. [Explanation of symbols]

[0048] 100, 200, 300, 400... battery packs 1...Outer case 1X...first case 1Y…Second case 2...Core Pack 3...Surface plate 3a...Outer corner 3b…straight line area 4…Outer wall 5...Shock absorbing wall 5X...First shock absorbing wall 5Y...Second shock absorbing wall 5a...Protruding part 5b…Slanted surface 5c…Central part 6...Main body wall 7...Shock absorption gap 7a...Opening 8...Connecting flange 8a...Connecting ridges 9...Connecting rib 10...Vertical rib 11...Lower end opening 12...Hollow part 13...Reinforcing rib 15...Grip 19...Set screw

Claims

1. a core pack that stores a plurality of batteries; an outer case that houses the core pack, the outer case is a box-shaped case having an outer peripheral wall connected to the outer peripheral edges of a pair of surface plates, The outer peripheral wall provided at the corner portion of the surface plate is a shock absorbing gap formed by separating a shock absorbing wall on the outer surface and a main body wall disposed inside the shock absorbing wall at a predetermined interval; The shock absorbing gaps are opened on both sides of the pair of surface plates, an intermediate portion of the outer peripheral wall located between the projected corner portions does not protrude outward beyond the tip end portion of the impact absorbing wall of the projected corner portion; a tip end portion of the shock absorbing wall in a height direction extends to the position of the surface plate, The battery pack is such that the surface plate does not receive an impact before the leading edge of the impact absorbing wall.

2. A core pack that stores a plurality of batteries; an outer case that houses the core pack, the outer case is a box-shaped case having an outer peripheral wall connected to the outer peripheral edges of a pair of surface plates, The outer peripheral wall provided at the corner portion of the surface plate is a shock absorbing gap formed by separating a shock absorbing wall on the outer surface and a main body wall disposed inside the shock absorbing wall at a predetermined interval; The shock absorbing gap is opened on the surface plate side, The outer case is the surface plate; a box-shaped first case formed by integrally molding the outer peripheral wall of the surface plate; a second case that closes the opening of the first case, The first case and the second case are a connecting flange that connects the main body wall and the shock absorbing wall; the first case and the second case are connected via the connecting flange, an intermediate portion of the outer peripheral wall located between the projected corner portions does not protrude outward beyond the tip end portion of the impact absorbing wall of the projected corner portion; a tip end portion of the shock absorbing wall in a height direction extends to the position of the surface plate, The battery pack is such that the surface plate does not receive an impact before the leading edge of the impact absorbing wall.

3. A core pack that stores a plurality of batteries; an outer case that houses the core pack, the outer case is a box-shaped case having an outer peripheral wall connected to the outer peripheral edges of a pair of surface plates, The outer peripheral wall provided at the corner portion of the surface plate is a shock absorbing gap formed by separating a shock absorbing wall on the outer surface and a main body wall disposed inside the shock absorbing wall at a predetermined interval; The shock absorbing gap is opened on the surface plate side, The outer peripheral wall is a connecting rib that locally connects the shock absorbing wall and the main body wall; an intermediate portion of the outer peripheral wall located between the projected corner portions does not protrude outward beyond the tip end portion of the impact absorbing wall of the projected corner portion; a tip end portion of the shock absorbing wall in a height direction extends to the position of the surface plate, The battery pack is such that the surface plate does not receive an impact before the leading edge of the impact absorbing wall.

4. A core pack that stores a plurality of batteries; an outer case that houses the core pack, the outer case is a box-shaped case having an outer peripheral wall connected to the outer peripheral edges of a pair of surface plates, The outer peripheral wall provided at the corner portion of the surface plate is a shock absorbing gap formed by separating a shock absorbing wall on the outer surface and a main body wall disposed inside the shock absorbing wall at a predetermined interval; The shock absorbing gap is opened on the surface plate side, The shock absorbing wall is A longitudinal rib protruding from the outer surface is integrally formed along the tip edge, an intermediate portion of the outer peripheral wall located between the projected corner portions does not protrude outward beyond the tip end portion of the impact absorbing wall of the projected corner portion; a tip end portion of the shock absorbing wall in a height direction extends to the position of the surface plate, The battery pack is such that the surface plate does not receive an impact before the leading edge of the impact absorbing wall.

5. A core pack that stores a plurality of batteries; an outer case that houses the core pack, the outer case is a box-shaped case having an outer peripheral wall connected to the outer peripheral edges of a pair of surface plates, The outer peripheral wall provided at the corner portion of the surface plate is a shock absorbing gap formed by separating a shock absorbing wall on the outer surface and a main body wall disposed inside the shock absorbing wall at a predetermined interval; The shock absorbing gap is opened on the surface plate side, The corner portion of the surface plate has a curved portion that curves at a predetermined radius of curvature, The opening of the shock absorbing gap is a slit that curves along the curved portion of the corner portion of the surface plate, an intermediate portion of the outer peripheral wall located between the projected corner portions does not protrude outward beyond the tip end portion of the impact absorbing wall of the projected corner portion; a tip end portion of the shock absorbing wall in a height direction extends to the position of the surface plate, The battery pack is such that the surface plate does not receive an impact before the leading edge of the impact absorbing wall.

6. 6. The battery pack according to claim 1, The opening width (W1) of the shock absorbing gap is 2 mm or more.

7. 7. The battery pack according to claim 1, the exterior case has a grip, The outer case is The battery pack has the shock absorbing walls provided at the corners on both sides of the outer peripheral wall located opposite the grip.

8. The battery pack according to any one of claims 1 to 7, The surface of the tip edge of the shock absorbing wall is The battery pack has a protruding portion that protrudes beyond the center of the outer peripheral wall.

9. 9. The battery pack according to claim 8, The outer surface of the shock absorbing wall is A battery pack having an inclined surface that protrudes from the center toward the leading edge.

10. 10. The battery pack according to claim 8 or 9, The overall shape of the surface plate is polygonal, The battery pack has an outer peripheral wall connected to a linear region of the polygonal surface plate, and both ends of the linear region are formed as the protrusions.

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