Battery pack and battery pack group

Abstract

To improve the reusability of battery packs. [Solution] The rectangular battery pack 1 is provided with a first uneven portion 10 and a second uneven portion 20. The first uneven portion 10 has a first protrusion 11 on which a part of the first outer surface S1 of a pair of first outer surfaces S1 and second outer surfaces S2 facing in opposite directions is convex, and a first recess 12 on which the other part of the first outer surface S1, separate from the first protrusion 11, is recessed. The second uneven portion 20 has a second protrusion 21 on which a part of the second outer surface S2 is convex and is provided in a region that is covered by the first recess 12 when viewed in a predetermined direction through the direction that the first outer surface S1 and the second outer surface S2 face, and a second recess 22 on which the other part of the second outer surface S2, separate from the second protrusion 21, is recessed and is provided in a region that covers the first protrusion 11 when viewed in a predetermined direction.

Description

Technical Field

[0001] This invention relates to an in-vehicle battery pack and a battery pack group provided with a plurality of such battery packs.

Background Art

[0002] Among battery packs for vehicle drive mounted on vehicles, there are some in which a plurality of modules are housed in a case. In each of the modules, a plurality of battery cells are arranged in parallel. As one such battery pack, for example, Patent Document 1 proposes a structure in which a plurality of battery cells are housed in a rectangular parallelepiped box-shaped case.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, the above-described in-vehicle battery pack may be transferred to a reuse facility such as a charging station or an emergency power storage facility and reused after being mounted on a vehicle and used. When reusing an in-vehicle battery pack as a battery pack for a reuse facility in this way, it is effective to use a battery pack group in which a plurality of battery packs are connected in order to ensure the charge-discharge capacity. When reusing a battery pack in a reuse facility, if the battery pack is disassembled into modules and battery cells and then the modules and battery cells are reconnected, although the modules and battery cells of the battery pack are easy to use in the reuse facility, operations such as disassembling and reconnecting the battery pack for reuse are required.

[0005] When reusing battery packs in a reuse facility without disassembling them, depending on the shape of the battery packs, it may be difficult to directly connect multiple battery packs together, or even if they can be directly connected, the connection may be unstable. This may lead to the problem of not being able to reuse battery packs as they are. Therefore, there is room for improvement in enhancing the reusability of battery packs.

[0006] The battery pack and battery pack group described in this invention were devised in light of these challenges, and one of its objectives is to improve the reusability of battery packs. Furthermore, in addition to this objective, another objective of this invention is to achieve effects and benefits that cannot be obtained with conventional technology, derived from the various configurations shown in the "Modes for Carrying Out the Invention" described later. [Means for solving the problem]

[0007] The disclosed battery pack and battery pack group can be realized in the embodiments (application examples) disclosed below, and solve at least some of the above-mentioned problems. Each of embodiments from Embodiment 2 onward is an additional embodiment that can be appropriately selected and each of them is an embodiment that can be omitted. None of embodiments from Embodiment 2 onward disclose any embodiments or configurations that are essential to this case.

[0008] Embodiment 1. The disclosed battery pack is rectangular in shape and for use in vehicles. The battery pack comprises a first uneven portion and a second uneven portion. The first uneven portion has a first protrusion, which is a part of the first outer surface of a pair of first and second outer surfaces facing opposite directions, and a first recess, which is a part of the first outer surface other than the first protrusion. The second uneven portion has a second protrusion, which is a part of the second outer surface and is provided in a region covered by the first recess when viewed through in a predetermined direction in the direction that the first and second outer surfaces face, and a second recess, which is provided in a region that covers the first protrusion when viewed through in the predetermined direction, and is a part of the second outer surface other than the second protrusion.

[0009] Embodiment 2. In Embodiment 1 described above, it is preferable that the first protrusion and the second protrusion have a tapered surface or a rounded surface that narrows towards the tip. Embodiment 3. In Embodiment 1 or 2 described above, it is preferable that the first outer surface is the upper surface facing upward in the orientation of the battery pack when mounted in a vehicle, and the second outer surface is the lower surface facing downward in the orientation of the battery pack when mounted in a vehicle. Furthermore, it is preferable that the first uneven portion is the upper uneven portion provided on the upper surface, and the second uneven portion is the lower uneven portion provided on the lower surface.

[0010] Embodiment 4. In Embodiment 3 described above, it is preferable that the first protrusion in the upper uneven portion has a first portion extending along a horizontal first direction and a second portion extending along a second direction that is horizontal and intersects the first direction when mounted on a vehicle. In this case, it is preferable that the second recess in the lower uneven portion has a third portion that engages with the first portion and a fourth portion that engages with the second portion.

[0011] Embodiment 5. In an embodiment including Embodiment 1 described above, it is preferable that the first outer surface is a first side surface that faces horizontally in the orientation of the battery pack when mounted in a vehicle, and the second outer surface is a second side surface that faces horizontally in the orientation of the battery pack when mounted in a vehicle. Furthermore, it is preferable that the first uneven portion is a first side uneven portion provided on the first side surface, and the second uneven portion is a second side uneven portion provided on the second side surface.

[0012] Embodiment 6. In a battery pack group in which multiple battery packs of the embodiment including Embodiment 3 above are stacked vertically, it is preferable that the multiple battery packs are stacked such that the centers of gravity of the battery packs overlap when viewed in the vertical direction. Embodiment 7. In a battery pack group in which multiple battery packs of the embodiment including Embodiment 1 above are connected, it is preferable that each of the multiple battery packs has brackets for connecting the battery packs to each other that protrude from the four corners when viewed in the vertical direction. Embodiment 8. In a battery pack group in which a plurality of battery packs of the embodiment including Embodiment 1 above are connected, it is preferable that a friction material is provided at the location where the first uneven portion and the second uneven portion come into contact in the connected battery packs. [Effects of the Invention]

[0013] According to the disclosed battery pack and battery pack group, multiple battery packs can be stably and directly connected to each other, thereby improving the reusability of the battery packs. [Brief explanation of the drawing]

[0014] [Figure 1] This is a perspective view showing a battery pack according to one embodiment. [Figure 2] This is a plan view showing a battery pack according to one embodiment. [Figure 3] This is a plan view showing a battery pack of a first modified example according to one embodiment. [Figure 4] This is a plan view showing a battery pack of a second modified example according to one embodiment. [Figure 5] This is a cross-sectional view showing an enlarged view of the main part of a battery pack according to one embodiment. [Figure 6] This is a perspective view showing a group of battery packs according to one embodiment. [Modes for carrying out the invention]

[0015] Embodiments of the battery pack and battery pack group will be described with reference to the drawings. The embodiments shown below are merely illustrative, and there is no intention to exclude various modifications or applications of technologies not explicitly shown in the embodiments below. Each configuration of the embodiments can be modified in various ways without departing from their spirit. Furthermore, they can be selected or combined as needed.

[0016] The battery pack of this embodiment is for vehicle use and is used, for example, as a battery for vehicle drive. The type of vehicle in which such a battery is mounted is not particularly limited. For example, it can be applied as a vehicle drive battery to an electric vehicle (EV, Electric Vehicle), a hybrid electric vehicle (HEV, Hybrid Electric Vehicle), a plug-in hybrid electric vehicle (PHEV, Plug-in Hybrid Electric Vehicle), etc. A plug-in hybrid electric vehicle means a hybrid electric vehicle capable of external charging of the battery or external power supply from the battery. A plug-in hybrid electric vehicle is provided with a charging port (inlet) for inserting a charging cable through which electric power is supplied from an external charging facility and an outlet for external power supply.

[0017] The battery pack group of this embodiment is formed by connecting a plurality of battery packs, and can also be said to be in a form in which the battery packs removed from the vehicle are reused in a reuse facility. The form of the battery pack group (that is, the form in which a plurality of battery packs are connected) includes a form in which a plurality of battery packs are stacked vertically, a form in which a plurality of battery packs are connected horizontally (so-called "horizontally connected"), and combinations thereof.

[0018] In the description of this embodiment, directions based on the posture of the battery pack during vehicle mounting are used, and each direction is defined as follows. The direction of gravity is taken as downward, and the opposite is taken as upward ("UP" in the figure). Also, the forward direction of the vehicle is taken as forward ("FR" in the figure), the reverse direction as backward, and the left side ("LH" in the figure) and the right side are defined based on the forward direction.

[0019] [I. One Embodiment] FIG. 1 is a perspective view showing a battery pack 1 according to an embodiment. FIG. 2 is a plan view showing the battery pack 1 according to an embodiment. FIGS. 3 and 4 are plan views showing modified battery packs 1′, 1″ according to an embodiment, FIG. 3 shows the battery pack 1′ of the first modification, and FIG. 4 shows the battery pack 1″ of the second modification. FIG. 5 is a cross-sectional view showing an enlarged main part of the battery pack 1 according to an embodiment. FIG. 6 is a perspective view showing a battery pack group 1G according to an embodiment.

[0020] [1. Structure] [1-1. Battery Pack] As shown in FIG. 1, the battery pack 1 has a rectangular parallelepiped outer shape. The outer surface of this battery pack 1 has six surfaces including an upper surface 2U (first outer surface) facing upward, a lower surface 2D (second outer surface) facing downward, a front surface 2F (first side surface, first outer surface) facing forward, a rear surface 2B (second side surface, second outer surface) facing backward, a left surface 2L facing left, and a right surface 2R facing right in the posture of the battery pack 1 when mounted in a vehicle. When the front surface 2F, the rear surface 2B, the left surface 2L, and the right surface 2R are not distinguished, they are called "side surfaces 2S".

[0021] In the battery pack 1 of the present embodiment, a first concavo-convex portion 10 and a second concavo-convex portion 20 are provided, and these first concavo-convex portion 10 and second concavo-convex portion 20 are provided with a concavo-convex structure corresponding to each other. The first concavo-convex portion 10 and the second concavo-convex portion 20 exemplified in the present embodiment are provided such that when two adjacent battery packs 1 are connected, the first concavo-convex portion 10 in one battery pack 1 and the second concavo-convex portion 20 in the other battery pack 1 are engaged or fitted. Here, the "engagement or fitting" means that even if an external force that displaces the battery pack 1 in a direction orthogonal to the direction in which the concavo-convex portions 10, 20 are recessed or protruded is applied, the displacement is structurally restricted and they are engaged with each other. Here, the "fitting" is not limited to a form in which they fit tightly, and includes, for example, a form in which they fit loosely.

[0022] In this embodiment, the first uneven portion 10 is exemplified by an upper uneven portion 30 provided on the upper surface 2U and a front uneven portion 50 (first side uneven portion) provided on the front surface 2F. The second uneven portion 20 is exemplified by a lower uneven portion 40 provided on the lower surface 2D and a rear uneven portion 60 (second side uneven portion) provided on the rear surface 2B. The first and second forms of the first and second uneven portions 10 and 20 will be described below. In the first form, the upper and lower uneven portions 30 and 40 will be described. In the second form, the front and rear uneven portions 50 and 60 will be described.

[0023] ==First form== The upper uneven portion 30 has an upper convex portion 31 (first convex portion, only one is referenced in Figure 1) whose upper surface 2U is partially convex, and an upper concave portion 32 (first concave portion, only one is referenced in Figure 1) whose upper surface 2U is partially concave. The upper convex portion 31 is a part of the upper surface 2U that is convex. The upper concave portion 32 is a part of the upper surface 2U that is concave, separate from the upper convex portion 31. The vertical distance between the uppermost part of the upper convex portion 31 and the lowermost part of the upper concave portion 32 can be called the upper convex dimension of the upper convex portion 31 when it is convex in the vertical direction, and can also be called the upper concave dimension of the upper concave portion 32 when it is concave in the vertical direction.

[0024] The lower uneven portion 40 has a lower protrusion 41 (second protrusion, only one is referenced in Figure 1) on which the lower surface 2D is partially convex, and a lower recess 42 (second recess, only one is referenced in Figure 1) on which the lower surface 2D is partially recessed. The lower protrusion 41 is a portion of the lower surface 2D that is convex. The lower recess 42 is a portion of the lower surface 2D that is recessed, separate from the lower protrusion 41. The vertical distance between the lowest part of the lower protrusion 41 and the highest part of the lower recess 42 can be called the lower protrusion dimension of the lower protrusion 41, and can also be called the lower recess dimension of the lower recess 42, which is recessed in the vertical direction. The lower protrusion dimension and the lower recess dimension are set to be the same as the upper protrusion dimension and the upper recess dimension.

[0025] The upper convex portion 31 and the lower concave portion 42 are provided in corresponding areas. Specifically, as shown in Figure 2, the lower protrusion 41 is located in the region covered by the upper recess 32 in a plan view (view in a predetermined direction) with vertical projection. In other words, the upper recess 32 is located in the region that covers the lower protrusion 41 in a plan view. Furthermore, the lower recess 42 is located in the region that covers the upper protrusion 31 in a plan view with vertical projection. In other words, the upper protrusion 31 is located in the region that covers the lower recess 42 in a plan view.

[0026] When the two battery packs 1 exemplified in this embodiment are stacked one above the other, the lower protrusion 41 of the upper battery pack 1 is inserted into the upper recess 32 of the lower battery pack 1, and the upper protrusion 31 of the lower battery pack 1 is inserted into the lower recess 42 of the upper battery pack 1. In this case, the lower protrusion 41 and the upper recess 32 engage or fit together, and the lower recess 42 engage or fit together with the upper protrusion 31.

[0027] As illustrated in Figures 1 and 2, the upper convex portion 31 and the lower convex portion 41, as well as the upper recess 32 and the lower recess 42, each extend in the left-right direction. Therefore, the upper convex portion 31 and the lower convex portion 41 can be described as protrusions, and the upper recess 32 and the lower recess 42 can be described as grooves. Furthermore, the upper protrusion 31 and lower protrusion 41, as well as the upper recess 32 and lower recess 42, are all provided in multiple locations, arranged in a front-to-back direction.

[0028] However, the upper convex portion 31 and the lower convex portion 41, as well as the upper recess 32 and the lower recess 42, may extend in any direction along the horizontal direction (i.e., the extending direction of the upper surface 2U and the lower surface 2D), and may not be in an extended form but may be partially (so to speak, point-like) convex or recessed form. Furthermore, the upper convex portion 31 and the lower convex portion 41, as well as the upper recess 32 and the lower recess 42, may not be provided in multiple locations but may be provided in only one location.

[0029] If an external force is applied that displaces the upper battery pack 1 in the front-to-back direction, the displacement of the lower protrusion 41 of the upper battery pack 1 in the front-to-back direction is structurally restricted by the upper recess 32 of the lower battery pack 1. Similarly, the displacement of the lower recess 42 of the upper battery pack 1 in the front-to-back direction is structurally restricted by the upper protrusion 31 of the lower battery pack 1. The protrusions 30 and 40 are provided such that the upper protrusion 31 and upper recess 32 of the upper protrusion 30 and the lower recess 42 and lower protrusion 41 of the lower protrusion 40 engage or fit together in this manner.

[0030] Hereinafter, a first modified example of the upper uneven portion 30 and lower uneven portion 40 described above will be explained with reference to Figure 3, and a second modified example will be explained with reference to Figure 4. The configurations of the first and second modified examples are the same as those of the upper uneven portion 30 and lower uneven portion 40 described above, except for the points explained here. In the first modified example, the upper uneven portion 30' is provided with an upper convex portion 31' extending in two directions. In this example, the upper convex portion 31' is provided on the upper surface 2U' with a first upper convex portion 33' (first portion) extending along the front-to-back direction (first direction) and a second upper convex portion 34' (second portion) extending along the left-to-right direction (second direction).

[0031] On this upper uneven portion 30', an upper recess 32' (only one is indicated by a reference numeral in Figure 3) is provided as a recessed portion on the upper surface 2U', separate from the upper protrusions 33' and 34'. Figure 3 shows an example in which a cross-shaped upper protrusion 31' is arranged by the first upper protrusion 33' and the second upper protrusion 34'. In the first modified example, the lower uneven portion 40' has a lower protrusion 41' in a plan view seen through in the vertical direction, in the area covered by the upper recess 32', and a lower recess 42' (only one is referenced in Figure 3) in the area covering the upper protrusions 33' and 34'.

[0032] In this example, the lower recess 42' has a first lower recess 43' (third portion) extending in the front-to-back direction and a second lower recess 44' (fourth portion) extending in the left-to-right direction, both provided on the lower surface 2D'. When the battery packs 1' exemplified in the first modification are stacked vertically, the first lower recess 43' on the upper battery pack 1' engages with the first upper protrusion 33' on the lower battery pack 1', and the second lower recess 44' on the upper battery pack 1' engages with the second upper protrusion 34' on the lower battery pack 1'. In addition, the upper recess 32' on the lower battery pack 1' engages with the lower protrusion 41' on the upper battery pack 1'.

[0033] In the second modified example, the upper convex portion 30″ is provided with an annularly extending upper convex portion 31″, as shown in Figure 4. This upper convex portion 31″ includes a first portion 35″ extending in the left-right direction and a second portion 36″ extending in the front-back direction. Figure 4 illustrates an elliptical upper convex portion 31″.

[0034] On this upper uneven portion 30″, an upper recess 32″ is provided as a recessed portion separate from the upper convex portion 31″ on the upper surface 2U″. In the second modified example, the lower uneven portion 40″ is provided with a lower convex portion 41″ in a plan view seen through in the vertical direction, in the area covered by the upper concave portion 32″, and the lower concave portion 42″ is provided in the area covering the upper convex portion 31″.

[0035] In this example, the lower recess 42″ has a third portion 45″ extending in the left-right direction and a fourth portion 46″ extending in the front-back direction, both provided on the lower surface 2D″. When the battery packs 1″ exemplified in the second modification are stacked vertically, the lower recess 42″ (third portion 45″ and fourth portion 46″) provided on the upper battery pack 1″ engages with the upper protrusion 31″ (first portion 35″ and second portion 36″) provided on the lower battery pack 1″, and the lower protrusion 41″ provided on the upper battery pack 1″ engages with the upper recess 32″ provided on the lower battery pack 1″.

[0036] ==Second form== The front and rear uneven portions 50 and 60 are provided with a configuration in which "upper" is read as "front" and "lower" is read as "rear" as described in the first embodiment above. Specifically, as shown in Figure 1, the front recessed portion 50 has a front protrusion 51 (first side protrusion, first protrusion) on the front surface 2F which is partially protruding, and a front recess 52 (first side recess, first recess) on the front surface 2F which is partially recessed. The rear recessed portion 60 has a rear protrusion 61 (second side protrusion, second protrusion) on the rear surface 2B which is partially protruding, and a rear recess 62 (second side recess, second recess) on the rear surface 2B which is partially recessed.

[0037] Furthermore, the front convex portion 51 is located in a region covered by the rear concave portion 62 when viewed through in the front-to-back direction (side view, predetermined direction view), and the rear convex portion 61 is located in a region covered by the front concave portion 52 when viewed through in the front-to-back direction. In other words, the rear concave portion 62 is located in a region that covers the front convex portion 51 when viewed through in the front-to-back direction, and the front concave portion 52 is located in a region that covers the rear convex portion 61 when viewed through in the front-to-back direction.

[0038] ==Summary of First and Second Forms== The following provides a more detailed explanation of the uneven portions 30, 30′, 30″, 40, 40′, 40″, 50, and 60 of the first and second forms described above. The top surface 2U and the bottom surface 2D can be described as a pair of outer surfaces S1 and S2 facing opposite directions. Similarly, the front surface 2F and the rear surface 2B can be described as a pair of outer surfaces S1 and S2 facing opposite directions.

[0039] If one of the pair of outer surfaces is designated as the first outer surface S1 and the other as the second outer surface S2, then the first outer surface S1 includes the top surface 2U (either the top surface 2U or the bottom surface 2D) and the front surface 2F (either the front surface 2F or the rear surface 2B). The second outer surface S2 includes the bottom surface 2D (the other of the top surface 2U or the bottom surface 2D) and the rear surface 2B (the other of the front surface 2F or the rear surface 2B).

[0040] The first uneven portion 10, exemplified by the upper uneven portion 30, 30', 30″ and the front uneven portion 50, is provided on the first outer surface S1, and the second uneven portion 20, exemplified by the lower uneven portion 40, 40', 40″ and the rear uneven portion 60, is provided on the second outer surface S2. The first uneven portion 10 has a first convex portion 11, exemplified by the upper convex portions 31, 31', 31'' and the front convex portion 51, and a first recess 12, exemplified by the upper recess 32, 32', 32'' and the front recess 52. The second uneven portion 20 has a second convex portion 21, exemplified by the lower convex portions 41, 41', 41'' and the rear convex portion 61, and a second recess 22, exemplified by the lower recess 42, 42', 42'' and the rear recess 62.

[0041] ==Other== In addition, the first and second protrusions 11 and 21 illustrated in this embodiment have a tapered surface F1 or a rounded surface F2 that narrows towards the tip, as shown in Figure 5. The tapered surface F1 is provided in a planar shape. The rounded surface F2 is provided in a curved shape. In other words, the tapered surface F1 or rounded surface F2 is provided on the concave and concave portions 10 and 20 in such a way that the corners on the tip side of the protrusions 11 and 21 are chamfered. Figure 5 illustrates, for illustrative purposes, a configuration in which both the tapered surface F1 on the left side of the figure and the rounded surface F2 on the right side are provided on the protrusions 11 and 21. However, it is sufficient that at least one of the tapered surface F1 and the rounded surface F2 is provided on the protrusions 11 and 21.

[0042] [1-2. Battery Pack Group] As shown in Figure 6, in the battery pack group 1G, multiple battery packs 1 are connected together. Each battery pack 1 is shaped like a rectangular parallelepiped. In the battery pack group 1G illustrated in Figure 6, the battery packs 1 are connected front to back and stacked vertically. Alternatively, the battery packs 1 in the battery pack group 1G may also be connected left to right.

[0043] In the battery pack group 1G, multiple battery packs 1 (two in Figure 6) are stacked vertically so that their centers of gravity G overlap when viewed vertically. The battery pack 1 shown here has a rectangular shape when viewed vertically, and its center of gravity G is set at the point where the diagonals of this rectangle intersect. In this embodiment, the battery pack group 1G is provided with brackets 90 for connecting the battery packs 1 together.

[0044] As shown in Figures 1 and 2, the bracket 90 is attached to the side 2S of the battery pack 1. The bracket 90 is provided so as to extend horizontally from each of the four corners of the battery pack 1 when viewed from above. The bracket 90 described above is provided with an arm portion 91 that extends horizontally from the side 2S, and a main body portion 92 attached to the tip of the arm portion 91. The main body portion 92 is provided in a cylindrical shape with a space that passes through it vertically.

[0045] Here, as shown in Figure 6, of the two battery packs 1 connected front to back, the front (one) battery pack 1 is designated as the front battery pack 1F (first side battery pack), and the rear (the other) battery pack 1 is designated as the rear battery pack 1B (second side battery pack). Furthermore, of the four brackets 90, the two brackets provided on the front battery pack 1F at the right rear and left rear are designated as the first brackets 9A, and the two brackets provided on the rear battery pack 1B at the right front and left front are designated as the second brackets 9B.

[0046] If the first bracket 9A and the second bracket 9B are located in the same vertical region as the side surface 2S, there is a risk that the brackets 9A and 9B may interfere with each other when connecting the front battery pack 1F and the rear battery pack 1B. Therefore, in this embodiment, the bracket 90 is provided with a first bracket 9A only in the vertical region corresponding to the upper half of the side surface 2S, and a second bracket 9B only in the vertical region corresponding to the lower half of the side surface 2S.

[0047] The first bracket 9A and the second bracket 9B are positioned such that, with the front battery pack 1F and the rear battery pack 1B connected, the main body 92 of the first bracket 9A overlaps the main body 92 of the second bracket 9B above it. In other words, with the battery packs 1F and 1B connected, the brackets 9A and 9B are provided such that the space through which the main body 92 of the first bracket 9A passes through the space through which the main body 92 of the second bracket 9B passes coincide or overlap when viewed in the vertical direction.

[0048] In addition, in the battery pack group 1G illustrated in this embodiment, friction material 9 (only one location is indicated by a reference numeral in Figure 6) is provided at the location where the first uneven portion 10 and the second uneven portion 20 of the connected battery pack 1 come into contact. The friction material 9 is provided, for example, on the protrusions 11 and 21 of the uneven portions 10 and 20. Methods for providing the friction material 9 include bonding a sheet-like friction material 9 to the outer surface of the protrusions 11 and 21, or roughening the surface of the protrusions 11 and 21. However, the friction material 9 may be provided on either the first protrusion 11 or the second protrusion 21, or on at least one of the first recess 12 or the second recess 22.

[0049] [2. Action and Effects] Since the battery packs 1, 1', 1'' and battery pack group 1G of this embodiment are configured as described above, the following functions and effects can be obtained. (1) According to the battery pack 1,1',1″ of this embodiment, when multiple battery packs 1,1',1″ are connected, the misalignment of the connected battery packs 1,1',1″ can be structurally suppressed by inserting the second protrusion 21 into the first recess 12 and the first protrusion 11 into the second recess 22. Specifically, the recessed and protruding parts 10,20, in which the first recess 12 and the second protrusion 21 engage or fit together and the second recess 22 and the first protrusion 11 engage or fit together, can structurally restrict the relative positional displacement of the connected battery packs 1,1',1″. Therefore, when multiple in-vehicle battery packs 1,1',1″ are connected and reused, the battery packs 1,1',1″ can be stably and directly connected to each other. Furthermore, there is no need to disassemble or reconnect the battery packs 1,1′,1″ for reuse. Therefore, when reusing the in-vehicle battery packs 1,1′,1″, multiple battery packs 1,1′,1″ can be easily and stably directly connected to each other, thereby increasing the reusability of the battery packs 1,1′,1″.

[0050] (2) The first protrusion 11 and the second protrusion 21, which have a tapered surface F1 or a rounded surface F2 that narrows towards the tip, improve the ease of inserting the second protrusion 21 into the first recess 12 and improve the ease of inserting the first protrusion 11 into the second recess 22. This improves the ease of connecting the battery packs 1,1',1″ together. From this point of view, it also contributes to improving the reusability of the battery packs 1,1',1″.

[0051] (3) With a battery pack 1,1',1" provided with upper recessed parts 30,30',30" and lower recessed parts 40,40',40", misalignment of the battery packs 1,1',1" can be suppressed when the battery packs 1,1',1" are stacked one after the other. Specifically, the upper protrusions 31,31',31" of the upper recessed parts 30,30',30" are inserted into the lower recesses 42,42',42" of the lower recessed parts 40,40',40" of the battery pack 1,1',1" stacked on top of it. Along with this, the lower protrusions 41, 41', 41" of the lower protrusions 40, 40', 40" of the battery pack 1, 1', 1" stacked on top are inserted into the upper recesses 32, 32', 32" of the upper protrusions 30, 30', 30" of the upper protrusions 30, 30', 30" and the lower protrusions 40, 40', 40" of the upper and lower battery packs 1, 1', 1" work together to structurally suppress misalignment between the battery packs 1, 1', 1" and each other.

[0052] (4) The modified upper protrusions 30', 30'' have a first upper protrusion 33', first part 35'' extending in the front-rear direction and a second upper protrusion 34', second part 36'' extending in the left-right direction. The modified lower protrusions 40', 40'' have a first lower recess 43', third part 45'' extending in the front-rear direction and a second lower recess 44', fourth part 46'' extending in the left-right direction. Therefore, even if an external force is applied to one of the two battery packs 1', 1'' stacked vertically, causing the other to be displaced horizontally, the lower protrusions 40', 40'' engage with the upper protrusions 30', 30'' so as to catch on them, structurally restricting the misalignment between the two battery packs 1', 1'' stacked vertically. Thus, misalignment between the battery packs 1', 1'' can be further suppressed.

[0053] (5) With a battery pack 1 provided with a front recessed portion 50 and a rear recessed portion 60, when two battery packs 1 are placed side by side horizontally, misalignment between the battery packs 1 can be suppressed. Specifically, the front protrusion 51 of the front recessed portion 50 is inserted into the rear recess 62 of the rear recessed portion 60 provided on the battery pack 1 connected to its front. At the same time, the rear protrusion 61 of the rear recessed portion 60 of the battery pack 1 connected to its front is inserted into the front recess 52 of the front recessed portion 50. As a result, the front recessed portion 50 and the rear recessed portion 60 of two adjacent battery packs 1 cooperate to structurally suppress misalignment between the battery packs 1.

[0054] (6) In the battery pack group 1G of this embodiment, multiple battery packs 1 are stacked so that their centers of gravity G overlap when viewed in the vertical direction. Therefore, with a battery pack group 1G stacked so that the centers of gravity G overlap when viewed in the plan direction, the battery packs 1 can be stacked vertically stably, which helps to prevent the stacked battery packs 1 from collapsing. From this point of view as well, the reusability of the battery packs 1 is improved.

[0055] (7) The brackets 90 that connect the battery packs 1 together are provided on each battery pack 1, protruding from the four corners in a plan view. Therefore, the brackets 90 can be positioned in a location that does not interfere with the protrusions and recesses 10 and 20. Thus, the battery packs 1 can be connected to each other by the brackets 90 which are positioned without interfering with the protrusions and recesses 10 and 20. From this point of view as well, the reusability of the battery packs 1 can be further enhanced. Furthermore, the bracket 90 can also be used to secure the battery pack 1 to the vehicle when it is mounted in a vehicle. In other words, the bracket 90 can be used not only as a component to connect battery packs 1 to each other in a reuse facility, but also as a component to secure the battery pack 1 to the vehicle when it is mounted in a vehicle.

[0056] Furthermore, the bracket 90 illustrated in this embodiment is provided with a first bracket 9A and a second bracket 9B. By inserting a rod-shaped or string-shaped connecting device 99 (see Figure 6) through the space provided in the main body portion 92 of the brackets 9A and 9B, the relative positional misalignment between the front battery pack 1F and the rear battery pack 1B can be restricted by the connecting device 99, thereby further suppressing the positional misalignment between the battery packs 1F and 1B. (8) The friction material 9 provided at the points where the protrusions and recesses 10 and 20 of the connected battery pack 1 come into contact with each other can further suppress misalignment of the battery packs 1.

[0057] [II. Variant Examples] The embodiments described above are merely examples of many possible specific embodiments. For example, in Figure 1 of the above-described embodiment, the first outer surface S1 and the second outer surface S2 are shown to be approximately parallel, but it is not necessary for these outer surfaces S1 and S2 to be strictly parallel. The battery pack 1 of this embodiment only needs to include at least a first uneven portion 10 and a second uneven portion 20.

[0058] The protrusions and recesses 10,20 are not limited to being provided on the upper surface 2U and lower surface 2D or the front surface 2F and rear surface 2B, but may also be provided on the left surface 2L and right surface 2R. In this case, one embodiment provides a configuration in which "upper" is read as "left" and "down" is read as "right" as described in the first embodiment above.

[0059] The bracket 90 is not limited to being provided at the four corners of the battery pack 1 as described above in one embodiment, but may be provided at any location. For example, if the battery packs 1 in the battery pack group 1G are not connected front to back or left to right, but are simply stacked vertically, the bracket 90 can be attached to any location on the side 2S. This bracket 90 can be used not only to stably connect the battery packs 1 in a reuse facility, but also to fix the battery packs 1 to the reuse facility, and can also be used to securely fix the battery packs 1 to a vehicle.

[0060] Furthermore, the bracket 90 is not limited to the configuration in which the connecting device 99 is inserted as described above in one embodiment; any known structure in which the brackets 90 interlock with each other can be adopted. Alternatively, the bracket 90 may be provided with a plug for electrically connecting the battery packs 1 and a plug socket, and the bracket 90 may have an outlet structure in which the plug is inserted into an outlet. In addition, the bracket 90 may be omitted from the battery pack 1, and the tapered surface F1 and the rounded surface F2 may be omitted from the protrusions 11 and 21. [Explanation of Symbols]

[0061] 1,1′,1″ Battery Pack 10 First uneven part 11 First protrusion 12 First recess 1G Battery Pack Group 20 Second uneven part 21 Second protrusion 22 Second recess 30,30′,30″ Upper uneven part (first uneven part) 31,31′,31″ Upper convex part (first convex part) 32,32′,32″ Upper recess (first recess) 33' First upper convex part (first part) 34′ Second upper convex part (second section) 35″ 1st part 36″ 2nd part 40,40′,40″ Lower uneven part (second uneven part) 41, 41′, 41″ Lower convex section (second convex section) 42, 42′, 42″ Lower recess (second recess) 43′ First lower recess (third part) 44′ Second lower recess (fourth part) 45″ Third part 46″ 4th part 50 Front uneven section (first side uneven section, first uneven section) 51 Front convex part (first side convex part, first convex part) 52 Front recess (first side recess, first recess) 60 Rear uneven section (second side uneven section, second uneven section) 61 Rear convex section (second side convex section, second convex section) 62 Rear recess (second side recess, second recess) 9 Friction material 90 bracket F1 Tapered surface F2 curved surface G center of gravity S1 First outer surface S2 Second outer surface

Claims

1. A battery pack for vehicles that is shaped like a rectangular parallelepiped, A first convex portion having a first convex portion, which is a part of the first outer surface of a pair of first and second outer surfaces facing in opposite directions, and a first concave portion having a part of the first outer surface other than the first convex portion that is concave, The second outer surface comprises a second protrusion, which is provided in a region covered by the first recess when viewed in a predetermined direction through the direction in which the first and second outer surfaces face, and a second recess, which is provided in a region where the other part of the second outer surface, separate from the second protrusion, is recessed and covers the first protrusion when viewed in the predetermined direction. A battery pack characterized by the following features.

2. The first and second protrusions have tapered or rounded surfaces that narrow towards the tip. The battery pack according to claim 1, characterized in that...

3. The aforementioned first outer surface is the upper surface that faces upward when the battery pack is mounted in the vehicle. The aforementioned second outer surface is the lower surface that faces downward in the aforementioned orientation when mounted on a vehicle. The first uneven portion is an upper uneven portion provided on the upper surface, The second uneven portion is a lower uneven portion provided on the lower surface. The battery pack according to claim 1, characterized in that...

4. The first protrusion in the upper uneven portion has, in the orientation when mounted on a vehicle, a first portion extending along a horizontal first direction and a second portion extending along a horizontal second direction that intersects the first direction. The second recess in the lower uneven portion has a third portion that engages with the first portion and a fourth portion that engages with the second portion. The battery pack according to claim 3, characterized in that it is the battery pack according to claim 3.

5. The aforementioned first outer surface is the first side surface that faces horizontally in the orientation of the battery pack when mounted in a vehicle. The aforementioned second outer surface is a second side surface that faces horizontally in the aforementioned orientation when mounted on a vehicle. The first uneven portion is a first side uneven portion provided on the first side surface, The second uneven portion is a second side uneven portion provided on the second side surface. The battery pack according to claim 1, characterized in that...

6. A group of battery packs in which multiple battery packs according to claim 3 or 4 are stacked vertically, Multiple battery packs are stacked such that their centers of gravity overlap when viewed in the vertical direction. A group of battery packs characterized by the following features.

7. A group of battery packs comprising a plurality of battery packs according to any one of claims 1 to 5, Each of the multiple battery packs is provided with brackets for connecting the battery packs to each other, which protrude from the four corners when viewed from above. A group of battery packs characterized by the following features.

8. A group of battery packs comprising a plurality of battery packs according to any one of claims 1 to 5, In the connected battery pack, a friction material is provided at the point where the first uneven portion and the second uneven portion come into contact. A group of battery packs characterized by the following features.

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