Battery pack

Abstract

To provide a battery pack capable of reducing impact on power control devices due to collision load from the front of a vehicle.SOLUTION: A second front side wall 22D extends to the rear of a vehicle and to the right in a vehicle width direction from the right edge of a front wall 22B of a case 18 in the vehicle width direction. An upper joint piece 36A of a reinforcement member 36 is joined to the second front side wall 22D, and a lower joint piece 36C of the reinforcement member 36 is joined to a lower wall 22A. The reinforcement member 36 constitutes a closed cross-sectional structure portion 44 in which the cross section seen from a vehicle front-rear direction together with the second front side wall 22D and the lower wall 22A is a closed cross section.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a battery pack.

Background Art

[0002] The following Patent Document 1 discloses an invention related to a bracket for a power storage unit. In the prior art according to the following Patent Document 1, a battery unit including a plurality of battery cells is fixed to a battery case via a bracket for a power storage unit provided on its outer periphery.

Prior Art Document

Patent Document

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, in the above prior art, a power control device such as a junction box for controlling the power of the battery unit is arranged at the front part of the battery case, and this power control device is located near the front wall of the battery case.

[0005] However, in the above prior art, since the front wall of the battery case is not reinforced, when a collision load from the front side of the vehicle is input to the battery case, it is conceivable that this collision load will affect the power control device. That is, the above prior art has room for improvement from the viewpoint of reducing the influence on the power control device due to the collision load from the front side of the vehicle.

[0006] In consideration of the above facts, an object of the present invention is to obtain a battery pack capable of reducing the influence on a power control device due to a collision load from the front side of the vehicle.

Means for Solving the Problems

[0007] The battery pack according to the first embodiment is designed to be mounted on a vehicle with one side in a first direction facing the front of the vehicle, one side in a second direction perpendicular to the first direction facing the left side of the vehicle, and one side in a third direction perpendicular to the first and second directions facing the top of the vehicle, and comprises a plurality of battery cells arranged in a series and capable of supplying power to on-board equipment mounted on the vehicle, a power control device capable of controlling the power of the battery cells and located on one side in the first direction of the battery cells, and a case housing the battery cells and the power control device, wherein the case has a front wall portion located on one side in the first direction of the power control device, and extends from the peripheral edge of the front wall portion on one side in the second direction to the other side in the first direction and to one side in the second direction The case comprises a first front side wall portion, a second front side wall portion extending from the peripheral edge of the front wall portion on the other side in the second direction to the other side in the first direction and the other side in the second direction, a first joining piece joined to the first front side wall portion, and a second joining piece joined to the lower wall portion constituting the part of the case on the other side in the third direction, and a first reinforcing portion that together with the first front side wall portion and the lower wall portion can form a closed cross section structure in which the cross section viewed from the first direction is a closed cross section, and a second reinforcing portion that comprises a third joining piece joined to the second front side wall portion, and a fourth joining piece joined to the lower wall portion, and a second reinforcing portion that together with the second front side wall portion and the lower wall portion can form a closed cross section structure in which the cross section viewed from the first direction is a closed cross section.

[0008] According to the first embodiment of the battery pack, it can be mounted on a vehicle with one side in the first direction facing the front of the vehicle, one side in the second direction perpendicular to the first direction facing the left side of the vehicle, and one side in the third direction perpendicular to both the first and second directions facing the top of the vehicle.

[0009] Furthermore, the battery pack according to this embodiment includes a plurality of battery cells arranged in series and a power control device capable of controlling the power of these battery cells, and can supply the power stored in the battery cells to on-board equipment mounted in the vehicle. The battery pack according to this embodiment also includes a case in which the battery cells and the power control device are housed.

[0010] In this embodiment, the power control device is positioned on one side of the battery cell in the first direction, and the front wall of the case is located on the same side as the power control device in the first direction. Therefore, if a collision load is applied to the case from the front of the vehicle, the front wall of the case may be pushed to the other side in the first direction, potentially affecting the power control device.

[0011] In this embodiment, a first front side wall extends from the peripheral edge of the front wall on one side in the second direction to the other side in the first direction and to one side in the second direction, and a second front side wall extends from the peripheral edge of the front wall on the other side in the second direction to the other side in the first direction and to the other side in the second direction.

[0012] Furthermore, the first connecting piece of the first reinforcing part is joined to the first front side wall, and the second connecting piece of the first reinforcing part is joined to the lower wall that constitutes the other side of the case in the third direction. In addition, the first reinforcing part, together with the first front side wall and the lower wall, forms a closed cross-section structure on one side of the front wall in the second direction, with a cross-section that is closed when viewed from the first direction.

[0013] Furthermore, the third connecting piece of the second reinforcing section is joined to the second front side wall, and the fourth connecting piece of the second reinforcing section is joined to the lower wall of the case. In addition, the second reinforcing section, on the other side of the front wall in the second direction, together with the second front side wall and the lower wall, constitutes a closed cross-section structure whose cross-section when viewed from the first direction is a closed cross-section.

[0014] Therefore, in this embodiment, when a collision load from the front of the vehicle is applied to the front wall of the case, causing a bending deformation to occur at the boundary between the front wall and the first front side wall, the front wall is supported by the closed cross-sectional structure on one side in the second direction of the front wall.

[0015] Furthermore, when the collision load causes bending deformation to occur at the boundary between the front wall and the second front side wall, the front wall is supported by the closed cross-sectional structure on the other side in the second direction of the front wall.

[0016] As a result, in this embodiment, it is possible to suppress the propagation of deformation of the case caused by the collision load from the front wall portion to the other side in the first direction.

[0017] The battery pack according to the second embodiment is a battery pack according to the first embodiment in which the length of at least one of the first reinforcing portion and the second reinforcing portion in the second direction increases from one side in the first direction to the other side in the first direction.

[0018] According to the battery pack of the second embodiment, in at least one of the first reinforcing portion and the second reinforcing portion, the length in the second direction increases as it moves from one side of the first direction to the other side of the first direction. Therefore, in this embodiment, the second moment of area can be increased in the above-mentioned portion as it moves from one side of the first direction to the other side of the first direction.

[0019] Incidentally, the collision load from the front of the vehicle that is applied to the front wall is applied to the portion on one side in the first direction. Therefore, the bending moment generated in that portion by this collision load increases as it moves toward the other side in the first direction.

[0020] Furthermore, in this embodiment, as described above, the second moment of area in one of the parts increases as it moves from one side in the first direction to the other side in the first direction. Therefore, deformation due to the bending moment in the one part can be suppressed without excessively increasing the cross-section of the portion on one side in the first direction.

[0021] The battery pack according to the third embodiment is a battery pack according to the first or second embodiment, wherein the case further comprises a support portion that supports the power control device from the other side in the third direction, is joined to the lower wall portion on the other side in the first direction of the front wall portion, and together with the lower wall portion, constitutes a closed cross-section structure whose cross-section when viewed from the first direction is a closed cross-section.

[0022] According to the battery pack according to the third aspect, a support portion is provided on the case, and this support portion supports the power control device from the third other side. Further, the support portion is joined to the lower wall portion of the case on the other side in the first direction of the front wall portion of the case, and together with the lower wall portion, constitutes a closed cross-section structure portion whose cross-section viewed from the first direction is a closed cross-section.

[0023] Therefore, in this aspect, when the front wall portion of the case is displaced to the other side in the first direction due to a collision load from the vehicle front side, the front wall portion can be supported by the closed cross-section structure portion including the support portion.

[0024] The battery pack according to the fourth aspect is the battery pack according to the third aspect, wherein the case extends in the second direction so as to partially overlap with the support portion when viewed from the first direction on the vehicle rear side of the support portion, is joined to the lower wall portion, and further includes a third reinforcing portion capable of constituting a closed cross-section structure portion whose cross-section viewed from the second direction is a closed cross-section together with the lower wall portion.

[0025] According to the battery pack according to the fourth aspect, a third reinforcing portion is provided on the case, and this third reinforcing portion extends in the second direction so as to partially overlap with the support portion when viewed from the first direction on the vehicle rear side of the support portion. Further, the third reinforcing portion is joined to the lower wall portion of the case, and together with the lower wall portion, constitutes a closed cross-section structure portion whose cross-section viewed from the second direction is a closed cross-section.

[0026] Therefore, in this aspect, when the support portion of the case is displaced to the other side in the first direction due to a collision load from the vehicle front side, the support portion can be supported by the closed cross-section structure portion including the third reinforcing portion.

[0027] The battery pack according to the fifth aspect is the battery pack according to any one of the first to fourth aspects, wherein the power control device is arranged such that, when viewed from the third direction, the length in the second direction of the portion of the power control device overlapping with one of the first reinforcing portion and the second reinforcing portion is shorter than the length in the second direction of the portion of the one not overlapping with the power control device.

[0028] According to the fifth embodiment of the battery pack, when viewed from a third direction, a part of the power control equipment overlaps with one of the first and second reinforcement parts. The power control equipment is arranged such that the length in the second direction of the part that overlaps with the power control equipment in one of the parts is shorter than the length in the second direction of the part that does not overlap with the power control equipment in one of the parts.

[0029] Therefore, in this embodiment, a margin for deformation against collision loads from the vehicle width direction can be secured on the outer side of the power control equipment in the case in the vehicle width direction. [Effects of the Invention]

[0030] As described above, the battery pack according to the first embodiment has the excellent effect of reducing the impact on power control equipment due to collision loads from the front of the vehicle.

[0031] The battery pack according to the second embodiment has the excellent effect of ensuring rigidity against collision loads from the front of the vehicle while suppressing an increase in the weight of the case.

[0032] The battery pack according to the third embodiment has the excellent effect of further reducing the impact on power control equipment due to collision loads from the front of the vehicle.

[0033] The battery pack according to the fourth embodiment has the excellent effect of being able to suppress deformation of the case due to collision load from the front of the vehicle.

[0034] The battery pack according to the fifth embodiment has the excellent effect of reducing the impact on power control equipment due to collision loads from the front of the vehicle and collision loads from the outside in the width direction of the vehicle. [Brief explanation of the drawing]

[0035] [Figure 1]This is an enlarged plan view schematically showing the configuration of the main part (the part enclosed by the dashed line in Figure 5) of the battery pack case according to this embodiment. [Figure 2] This is a schematic cross-sectional view of the battery pack case according to this embodiment, as seen from the front of the vehicle (a cross-sectional view showing the state as if cut along line 2-2 in Figure 1). [Figure 3] This is a schematic cross-sectional view of the battery pack case according to this embodiment, as seen from the front of the vehicle (a cross-sectional view showing the state as if cut along line 3-3 in Figure 1). [Figure 4] This is a schematic cross-sectional view of the battery pack case according to this embodiment, as seen from the vehicle width side (a cross-sectional view showing the state when cut along line 4-4 in Figure 1). [Figure 5] This is a schematic plan view showing the configuration of the battery pack case according to this embodiment. [Figure 6] This is a schematic bottom view showing the battery pack according to this embodiment mounted on a vehicle. [Modes for carrying out the invention]

[0036] An example of a battery pack embodiment will be described below using Figures 1 to 6. As shown in Figure 6, the "battery pack 10" according to this embodiment is positioned such that one side in the longitudinal direction (first direction) is the front side of the "vehicle 12" on which the battery pack 10 is mounted, one side in the short direction (second direction) is the left side of the vehicle 12, and one side in the thickness direction (third direction) is the top side of the vehicle. Arrows FR shown as appropriate in each figure indicate the front side of the vehicle, arrows UP indicate the top side of the vehicle, and arrows LH indicate the left side in the vehicle width direction. Furthermore, the following explanation will proceed on the premise that the battery pack 10 is mounted on the vehicle 12.

[0037] First, the configuration of the vehicle body 14 of the vehicle 12 will be described. The vehicle body 14 includes a pair of steel side members 16 located on the lower side of the vehicle in the outer portion in the vehicle width direction of a steel floor panel (not shown). Each side member 16 is composed of a front portion 16A that constitutes the front portion of the vehicle and extends in the vehicle longitudinal direction, an extension portion 16B that extends from the front portion 16A to the rear of the vehicle and outward in the vehicle width direction, and a floor side portion 16C that extends linearly from the extension portion 16B to the rear of the vehicle.

[0038] Furthermore, the cross-sectional shape of the side member 16 is a hat shape with the upper side of the vehicle open when viewed from its extending direction. The side member 16 is joined to the floor panel by a joint (not shown) such as spot welding, thereby forming a closed cross-sectional structure together with the floor panel. In this embodiment, the main part of the battery pack 10 is arranged between the pair of side members 16.

[0039] As shown in Figure 5, the battery pack 10 consists of a "case 18" that forms its outer shell and a plurality of battery modules 20 arranged inside the case 18.

[0040] The case 18 is mainly made of metal and includes a cover (not shown) that covers the battery module 20 from the upper side of the vehicle and a case body 22 that supports the battery module 20 from the lower side of the vehicle.

[0041] The case body 22 is composed of a "lower wall portion 22A" which constitutes the lower part of the vehicle, a "front wall portion 22B" which constitutes the front part of the vehicle, a "first front side wall portion 22C" which constitutes the front left part of the vehicle, a "second front side wall portion 22D" which constitutes the front right part of the vehicle, a pair of outer side wall portions 22E which constitute the outer part in the width direction of the vehicle, and a rear wall portion (not shown) which constitutes the rear part of the vehicle.

[0042] The lower wall portion 22A has a main part with a constant length in the vehicle width direction and a thickness in the vehicle vertical direction, extending in the vehicle longitudinal direction. The battery module 20 is arranged in this portion. For convenience, the portion of the lower wall portion 22A in which the battery module 20 is arranged will be referred to as the battery support wall portion 22A1 below.

[0043] More specifically, the battery support wall 22A1 is provided with multiple sets of bead portions 22A2, each consisting of two bead portions. These bead portions 22A2 are recessed toward the lower side of the vehicle and extend in the vehicle width direction. In sets of adjacent bead portions 22A2 in the vehicle front-rear direction, a reinforcing member 24 is provided at the boundary between the bead portion 22A2 on the rear side of one set and the bead portion 22A2 on the front side of the other set.

[0044] The reinforcing member 24 extends in the vehicle width direction and spans between a pair of outer side wall portions 22E, and its cross-section, as viewed from the vehicle width direction, is hat-shaped with the lower side of the vehicle open. The reinforcing member 24 is joined to the battery support wall portion 22A1 and the outer side wall portion 22E by joints (not shown) such as spot welding, and together with the battery support wall portion 22A1, it forms a closed-section structure, with a closed cross-section as viewed from the vehicle width direction. Battery modules 20 are positioned on the front and rear sides of the reinforcing member 24.

[0045] The battery module 20 is composed of multiple "battery cells 26" arranged in a row in the vehicle width direction, with the thickness direction being the vehicle width direction, and these cells are connected by connecting members (not shown). The power stored in the battery module 20 is controlled via a "junction box 28" which is a power control device housed in the case body 22, and supplied to on-board equipment (not shown) mounted on the vehicle 12.

[0046] Furthermore, an outer side wall portion 22E is provided on the outer peripheral edge of the battery support wall portion 22A1 in the vehicle width direction. This outer side wall portion 22E includes a web portion 22E1 extending upward from the peripheral edge and a flange portion 22E2 extending outward in the vehicle width direction from the upper peripheral edge of the web portion 22E1. In addition, the portion of the outer side wall portion 22E other than the mounting location of the reinforcing member 24 is reinforced by a reinforcing member 30 extending in the vehicle longitudinal direction.

[0047] On the other hand, the portion of the lower wall 22A facing the front of the vehicle is an isosceles trapezoid shape, where the length in the vehicle width direction decreases as you move from the battery support wall 22A1 side toward the front of the vehicle when viewed from the vertical direction of the vehicle. The junction box 28 is located in this portion. For convenience, the portion of the lower wall 22A where the junction box 28 is located will be referred to as the control equipment support wall 22A3 below.

[0048] Furthermore, a front wall portion 22B is provided on the peripheral edge of the control equipment support wall portion 22A3 on the vehicle front side, a first front side wall portion 22C is provided on the peripheral edge of the control equipment support wall portion 22A3 on the left side in the vehicle width direction, and a second front side wall portion 22D is provided on the peripheral edge of the control equipment support wall portion 22A3 on the right side in the vehicle width direction.

[0049] The front wall portion 22B is composed of a web portion 22B1 extending upward and forward from the peripheral edge of the control equipment support wall portion 22A3 on the vehicle front side, and a flange portion 22B2 extending forward from the peripheral edge of the web portion 22B1 on the vehicle upper side.

[0050] The first front side wall portion 22C is composed of a web portion 22C1 extending upward from the left peripheral edge in the vehicle width direction of the control equipment support wall portion 22A3, and a flange portion 22C2 extending forward from the upper peripheral edge of the web portion 22C1.

[0051] The second front side wall portion 22D is composed of a web portion 22D1 extending upward from the right peripheral edge in the vehicle width direction of the control equipment support wall portion 22A3, and a flange portion 22D2 extending forward from the upper peripheral edge of the web portion 22D1 toward the front of the vehicle.

[0052] As shown in Figure 6, the flange portion 22B2 of the front wall portion 22B, the flange portion 22C2 of the first front side wall portion 22C, the flange portion 22D2 of the second front side wall portion 22D, and the flange portion 22E2 of the outer side wall portion 22E are attached to the side member 16 by mounting members 32 such as bolts.

[0053] In this embodiment, as shown in Figure 5, the vehicle-front portion of the case body 22, including the control equipment support wall portion 22A3, is characterized by being reinforced by a "reinforcement member 34" as a first reinforcement portion, a "reinforcement member 36" as a second reinforcement portion, a plurality of "reinforcement members 38" as a third reinforcement portion, and a plurality of "support members 40" as a support portion. The configuration of the vehicle-front portion of the case body 22 will be described in detail below.

[0054] The reinforcing member 34 is positioned on the left side in the vehicle width direction of the control equipment support wall 22A3. This reinforcing member 34 is composed of an "upper connecting piece 34A" as a first connecting piece that constitutes the left side in the vehicle width direction, an upper wall 34B that constitutes the upper part of the vehicle, a "lower connecting piece 34C" as a second connecting piece that constitutes the lower part of the vehicle, and a side wall 34D that connects the upper wall 34B and the lower connecting piece 34C.

[0055] The upper connecting piece 34A is joined to the first front side wall 22C, and the lower connecting piece 34C is joined to the control equipment support wall 22A3 by spot welding or the like (not shown). As a result, the reinforcing member 34, together with the first front side wall 22C and the control equipment support wall 22A3, constitutes a "closed cross-section structure 42" whose cross-section is closed when viewed from the front-rear direction of the vehicle. The reinforcing member 34 has a symmetrical configuration with respect to the center line CL of the reinforcing member 36, and the configuration of the reinforcing member 34 should be appropriately referred to in the configuration of the reinforcing member 36 described later.

[0056] As shown in Figure 1, the reinforcing member 36 is positioned on the right side in the vehicle width direction of the control equipment support wall 22A3. This reinforcing member 36 is composed of an "upper connecting piece 36A" as a third connecting piece that constitutes the left side in the vehicle width direction, an upper wall 36B that constitutes the upper part of the vehicle, a "lower connecting piece 36C" as a fourth connecting piece that constitutes the lower part of the vehicle, and a side wall 36D that connects the upper wall 36B and the lower connecting piece 36C.

[0057] More specifically, the upper wall portion 36B has a plate thickness direction that is in the direction of the vehicle's vertical axis, and is roughly trapezoidal or triangular in shape, with its length in the vehicle width direction increasing from the front to the rear of the vehicle when viewed from the vehicle's vertical axis. An upper joining piece 36A is provided on the right peripheral edge of the upper wall portion 36B in the vehicle width direction.

[0058] The upper joining piece 36A extends upward from the right peripheral edge of the upper wall portion 36B in the vehicle width direction and is positioned along the second front side wall portion 22D, and is joined to the second front side wall portion 22D by a joint (not shown) such as spot welding.

[0059] On the other hand, the side wall portion 36D extends downward from the left peripheral edge in the vehicle width direction and the rear peripheral edge of the upper wall portion 36B, and the lower connecting piece portion 36C is provided on the lower peripheral edge of the side wall portion 36D.

[0060] When viewed from the vertical direction of the vehicle, the lower connecting piece 36C has a left portion in the vehicle width direction that extends to the left relative to the left peripheral edge of the upper wall portion 36B in the vehicle width direction, and a rear portion that extends to the rear relative to the rear peripheral edge of the upper wall portion 36B. The lower connecting piece 36C is joined to the control equipment support wall portion 22A3 by a joint (not shown) such as spot welding.

[0061] Furthermore, the reinforcing member 36 configured as described above, together with the second front side wall portion 22D and the control equipment support wall portion 22A3, as shown in Figure 3, constitutes a "closed cross-section structure 44" whose cross-section when viewed from the front-rear direction of the vehicle is a closed cross-section.

[0062] The reinforcing member 38 is positioned at two locations: the boundary between the battery support wall 22A1 and the control equipment support wall 22A3, and at a predetermined distance from the boundary toward the front of the vehicle, and extends in the vehicle width direction. As shown in Figure 4, the reinforcing member 38 is composed of an upper wall 38A, a front wall 38B, a rear wall 38C, a connecting piece 38D, and a connecting piece 38E, and its cross-sectional shape, as viewed from the vehicle width direction, is a hat shape with the lower side of the vehicle open.

[0063] More specifically, the upper wall portion 38A constitutes the upper part of the reinforcing member 38 on the vehicle side, and the front wall portion 38B extends downward from the vehicle side peripheral edge of the upper wall portion 38A on the vehicle side. Then, the connecting piece portion 38D extends forward from the vehicle side peripheral edge of the front wall portion 38B on the vehicle side, and the connecting piece portion 38D is joined to the control equipment support wall portion 22A3 by a joint (not shown) such as spot welding.

[0064] On the other hand, the rear wall portion 38C extends downward from the peripheral edge of the upper wall portion 38A on the vehicle side. A connecting piece portion 38E extends downward from the peripheral edge of the rear wall portion 38C on the vehicle side, and the connecting piece portion 38E is joined to the control equipment support wall portion 22A3 by a joint (not shown) such as spot welding.

[0065] Furthermore, the reinforcing member 38, configured as described above, together with the control equipment support wall portion 22A3, constitutes a "closed cross-section structure portion 46" whose cross-section, when viewed from the vehicle width direction, is a closed cross-section.

[0066] Returning to Figure 5, the support members 40 are arranged in groups of three, symmetrically with respect to the center line CL, between the front wall portion 22B and the reinforcing member 38 on the front side of the vehicle, and between the reinforcing members 38 themselves. That is, the reinforcing member 38 on the front side of the vehicle is positioned on the rear side of the front row of support members 40, and the reinforcing member 38 on the rear side of the vehicle is positioned on the rear side of the rear row of support members 40.

[0067] As shown in Figure 2, the support member 40 is composed of an upper wall portion 40A, a side wall portion 40B, a side wall portion 40C, a connecting piece portion 40D, and a connecting piece portion 40E, and its cross-sectional shape when viewed from the vehicle width direction is a hat shape with the lower side of the vehicle open.

[0068] More specifically, the upper wall portion 40A constitutes the upper part of the support member 40 on the vehicle side, and is positioned lower than the upper wall portion 38A of the reinforcing member 38 in the vehicle's vertical direction. Furthermore, the weld bolts 48 used for attaching the junction box 28 are joined to the upper wall portion 40A by welding or other means (not shown), with their shaft portions 48A facing the vehicle's upper side.

[0069] Furthermore, a side wall portion 40B extends downward from the left peripheral edge of the upper wall portion 40A in the vehicle width direction, and a connecting piece portion 40D extends to the left in the vehicle width direction from the lower peripheral edge of the side wall portion 40B. The connecting piece portion 40D is joined to the control equipment support wall portion 22A3 by a joint (not shown) such as spot welding.

[0070] On the other hand, a side wall portion 40C extends downward from the right peripheral edge of the upper wall portion 40A in the vehicle width direction. A connecting piece portion 40E extends to the right in the vehicle width direction from the lower peripheral edge of the side wall portion 40C, and the connecting piece portion 40E is joined to the control equipment support wall portion 22A3 by a joint (not shown) such as spot welding.

[0071] Furthermore, the support member 40, configured as described above, together with the control equipment support wall 22A3, constitutes a "closed cross-section structure 50" whose cross-section, when viewed from the front-rear direction of the vehicle, is a closed cross-section. In addition, the support member 40 overlaps with the reinforcing member 38 when viewed from the front-rear direction of the vehicle.

[0072] Furthermore, as shown in Figure 1, the junction boxes 28 are supported by the front row support members 40 and the rear row support members 40, respectively, with the vehicle width direction as the longitudinal direction. Also, when viewed from above the vehicle, the junction boxes 28 supported by the rear row support members 40 are positioned such that the length L1 in the vehicle width direction of the portion of one of the reinforcing members 34 and 36 that overlaps with the junction box 28 is shorter than the length L2 in the vehicle width direction of the portion of that one that does not overlap with the junction box 28.

[0073] (Operation and effects of this embodiment) Next, the operation and effects of this embodiment will be described.

[0074] In this embodiment, as shown in Figure 6, the battery pack 10 can be mounted on the vehicle 12 with one longitudinal side facing the front of the vehicle, one short side perpendicular to the longitudinal direction facing the left side of the vehicle, and one thickness side perpendicular to both the longitudinal and short directions facing the top of the vehicle.

[0075] Furthermore, as shown in Figure 5, the battery pack 10 includes a plurality of battery cells 26 arranged in series and a junction box 28 that can control the power of these battery cells 26, and can supply the power stored in the battery cells 26 to on-board equipment mounted on the vehicle 12. The battery pack 10 also includes a case 18, in which the battery cells 26 and the junction box 28 are housed.

[0076] In this embodiment, the junction box 28 is positioned on the vehicle front side of the battery cell 26, and the front wall portion 22B of the case body 22 of the case 18 is located on the vehicle front side of the junction box 28. Therefore, if a collision load is applied to the case 18 from the vehicle front side, it is conceivable that the front wall portion 22B will be pushed towards the vehicle rear side and affect the junction box 28.

[0077] In this embodiment, a first front side wall portion 22C extends from the left peripheral edge of the front wall portion 22B in the vehicle width direction toward the rear of the vehicle and toward the left in the vehicle width direction, and a second front side wall portion 22D extends from the right peripheral edge of the front wall portion 22B in the vehicle width direction toward the rear of the vehicle and toward the right in the vehicle width direction.

[0078] Furthermore, the upper connecting piece 34A of the reinforcing member 34 is joined to the first front side wall portion 22C, and the lower connecting piece 34C of the reinforcing member 34 is joined to the lower wall portion 22A which constitutes the lower part of the case 18 on the vehicle side. In addition, the reinforcing member 34, together with the first front side wall portion 22C and the lower wall portion 22B, forms a closed cross-section structure 42 on the left side in the vehicle width direction of the front wall portion 22B, with a cross-section that is closed when viewed from the front-rear direction of the vehicle.

[0079] Furthermore, as shown in Figure 1, the upper connecting piece 36A of the reinforcing member 36 is joined to the second front side wall portion 22D, and the lower connecting piece 36C of the reinforcing member 36 is joined to the lower wall portion 22A. In addition, as shown in Figure 3, the reinforcing member 36, together with the second front side wall portion 22D and the lower wall portion 22A, forms a closed cross-section structure 44 on the right side in the vehicle width direction of the front wall portion 22B, with a cross-section that is closed when viewed from the front-rear direction of the vehicle.

[0080] Therefore, in this embodiment, when a collision load from the front of the vehicle is applied to the front wall portion 22B of the case 18, and a bending deformation is about to occur at the boundary between the front wall portion 22B and the first front side wall portion 22C, the front wall portion 22B is supported by the closed cross-sectional structure portion 42 on the left side in the vehicle width direction of the front wall portion 22B.

[0081] Furthermore, when the collision load causes bending deformation to occur at the boundary between the front wall portion 22B and the second front side wall portion 22D, the front wall portion 22B is supported by the closed cross-sectional structure portion 44 on the right side in the vehicle width direction of the front wall portion 22B.

[0082] As a result, in this embodiment, the deformation of case 18 caused by the collision load can be prevented from propagating from the front wall portion 22B to the rear of the vehicle. Therefore, in this embodiment, the impact of the collision load from the front of the vehicle on the junction box 28 can be reduced.

[0083] Furthermore, in this embodiment, the length of the reinforcing member 34 and the reinforcing member 36 in the vehicle width direction increases from the front side of the vehicle to the rear side of the vehicle. Therefore, in this embodiment, the second moment of area of ​​the reinforcing member 34 and the reinforcing member 36 can be increased from the front side of the vehicle to the rear side of the vehicle.

[0084] Incidentally, the collision load from the front of the vehicle that is input to the front wall portion 22B is input to the front portion of the reinforcing members 34 and 36. Therefore, the bending moment generated in the reinforcing members 34 and 36 by this collision load increases as it moves towards the rear of the vehicle.

[0085] Furthermore, in this embodiment, as described above, the second moment of area of ​​the reinforcing members 34 and 36 increases from the front of the vehicle towards the rear of the vehicle. Therefore, deformation of the reinforcing members 34 and 36 due to the bending moment can be suppressed without excessively increasing the cross-section of the front portion of the reinforcing members 34 and 36. As a result, in this embodiment, the rigidity of the case 18 against collision loads from the front of the vehicle can be ensured while suppressing an increase in the weight of the case 18.

[0086] Furthermore, in this embodiment, a support member 40 is provided on the case 18, and this support member 40 supports the junction box 28 from the lower side of the vehicle. The support member 40 is joined to the lower wall portion 22A on the rear side of the front wall portion 22B of the vehicle, and together with the lower wall portion 22A, it constitutes a closed-section structure portion 50 whose cross-section when viewed from the front-rear direction of the vehicle is a closed section.

[0087] Therefore, in this embodiment, when the front wall portion 22B is displaced towards the rear of the vehicle due to a collision load from the front of the vehicle, the closed cross-section structure portion 50 including the support member 40 can support the front wall portion 22B. Thus, in this embodiment, the impact of the collision load from the front of the vehicle on the junction box 28 can be further reduced.

[0088] Furthermore, in this embodiment, a reinforcing member 38 is provided on the case 18, and this reinforcing member 38 extends in the vehicle width direction on the rear side of the support member 40 of the vehicle, so as to partially overlap with the support member 40 when viewed from the front-rear direction of the vehicle. In addition, the support member 40 is joined to the lower wall portion 22A of the case 18 and together with the lower wall portion 22A, constitutes a closed-section structure portion 50 whose cross-section when viewed from the vehicle width direction is a closed section.

[0089] Therefore, in this embodiment, when the support member 40 is displaced towards the rear of the vehicle due to a collision load from the front of the vehicle, the support member 40 can be supported by the closed cross-section structure 50 including the reinforcing member 38. Thus, in this embodiment, deformation of the case 18 due to a collision load from the front of the vehicle can be suppressed.

[0090] In addition, in this embodiment, when viewed from the vertical direction of the vehicle, a portion of the junction box 28 overlaps with the reinforcing member 36. The junction box 28 is positioned such that the length L1 in the vehicle width direction of the portion of the reinforcing member 36 that overlaps with the junction box 28 is shorter than the length L2 in the vehicle width direction of the portion of the reinforcing member 36 that does not overlap with the junction box 28.

[0091] Therefore, in this embodiment, a margin for deformation against collision loads from the vehicle width direction can be secured on the outer side of the junction box 28 in the vehicle width direction in case 18. Thus, in this embodiment, the impact on the junction box 28 from collision loads from the front side of the vehicle and from collision loads from the outer side in the vehicle width direction can be reduced.

[0092] <Supplementary explanation of the above embodiment> (1) In the above-described embodiment, the junction box 28 was placed in the front part of the case 18. However, depending on the specifications of the vehicle 12, power control equipment such as a battery ECU (Electronic Control Unit) may be placed in the front part of the case 18.

[0093] (2) In the embodiments described above, the shapes of the reinforcing members 34 and 36 were trapezoidal or triangular when viewed from the vertical direction of the vehicle, but the shapes of the reinforcing members 34 and 36 are not limited to these. For example, depending on the specifications of the battery pack 10, the shapes of the reinforcing members 34 and 36 when viewed from the vertical direction of the vehicle may be rectangular along the first front side wall portion 22C or the second front side wall portion 22D. [Explanation of symbols]

[0094] 10 battery packs 12 vehicles 18 cases 22A Lower wall part 22B Front wall 22C 1st front side wall section 22D Second front side wall section 26 battery cells 28. Junction Box (Power Control Equipment) 34 Reinforcement member (first reinforcement section) 34A Upper joint piece (first joint piece) 34C Lower joint piece (second joint piece) 36 Reinforcement member (second reinforcement section) 36A Upper joint piece (3rd joint piece) 36C Lower joint piece (4th joint piece) 38 Reinforcement member (third reinforcement section) 42 Closed section structure 44 Closed section structure 46 Closed section structure 50 Closed section structure

Claims

1. The device can be mounted on a vehicle with one side of the first direction facing the front of the vehicle, one side of the second direction perpendicular to the first direction facing the left side of the vehicle, and one side of the third direction perpendicular to both the first and second directions facing the top of the vehicle. A battery cell arranged in a series and capable of supplying power to on-board equipment mounted on the vehicle, A power control device is provided which allows control of the power of the battery cell and which is located on one side of the battery cell in the first direction. A case in which the battery cell and the power control device are housed, Equipped with, The aforementioned case is, The front wall portion located on one side of the first direction of the power control device, A first front side wall portion extending from the peripheral edge on one side in the second direction of the front wall portion to the other side in the first direction and to the side in the second direction, A second front side wall portion extending from the peripheral edge of the front wall portion on the other side in the second direction to the other side in the first direction and the other side in the second direction, The first reinforcing portion comprises a first joining piece joined to the first front side wall portion and a second joining piece joined to the lower wall portion constituting the other side of the case in the third direction, and together with the first front side wall portion and the lower wall portion, the first reinforcing portion constitutes a closed cross-section structure whose cross-section when viewed from the first direction is a closed cross-section, A second reinforcing portion comprises a third joining piece joined to the second front side wall portion and a fourth joining piece joined to the lower wall portion, and together with the second front side wall portion and the lower wall portion, constitutes a closed cross-section structure whose cross-section when viewed from the first direction is a closed cross-section, A battery pack that has [a certain feature].

2. The length of at least one of the first reinforcing portion and the second reinforcing portion in the second direction is increasing from one side in the first direction to the other side in the first direction. The battery pack according to claim 1.

3. The case further comprises a support portion that supports the power control device from the other side in the third direction, is joined to the lower wall portion on the other side in the first direction of the front wall portion, and together with the lower wall portion, constitutes a closed cross-section structure whose cross-section when viewed from the first direction is a closed cross-section. The battery pack according to claim 2.

4. The case further comprises a third reinforcing portion which extends in the second direction on the rear side of the vehicle of the support portion so as to partially overlap with the support portion when viewed from the first direction, is joined to the lower wall portion, and together with the lower wall portion, constitutes a closed cross-section structure whose cross-section when viewed from the second direction is a closed cross-section. The battery pack according to claim 3.

5. The power control device is arranged such that, when viewed from the third direction, the length in the second direction of the portion of the first reinforcing portion and the second reinforcing portion that overlaps with the power control device is shorter than the length in the second direction of the portion of the first reinforcing portion that does not overlap with the power control device. A battery pack according to any one of claims 1 to 4.

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