Battery structure of vehicle

Abstract

To protect a battery module against a collision load in a vehicle collision.SOLUTION: The present invention comprises the battery modules 11 which are arranged below the floor panel 90 of the vehicle, the battery frame 21 which covers around the battery modules 11 and supports the battery modules 11 in the vehicle plan view, and the connecting member 40 which connects the battery frame 21 and the battery modules 11, wherein the connecting member 40 comprises the deformation promoting portion 50 which promotes the deformation against the collision load inputted to the battery modules 11 from the battery frame 21 which is positioned on the side of the battery frame 21 relative to the fixation portion 48 fixed to the battery modules 11.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a battery structure for a vehicle that includes a battery module arranged under a floor of the vehicle and a battery frame that covers the periphery of the battery module in a plan view of the vehicle. [Background technology]

[0002] A conventional vehicle battery structure having a battery frame that surrounds the battery module when the vehicle is viewed from above and a connecting member that connects the battery frame to the battery module is disclosed as having a battery side bracket, as exemplified in Patent Document 1 below.

[0003] The battery-side bracket of Patent Document 1 is an outer wall body that is placed on the outer periphery of the battery pack, which corresponds to the battery module, and is said to have the function of protecting the battery pack from impact loads (see, for example, paragraphs

[0021] to

[0030] of Patent Document 1 below).

[0004] Specifically, the battery-side bracket has a web portion that corresponds to the battery frame made of an extruded material with an internal cavity, and a flange portion that corresponds to the connecting member. The flange portion protrudes from the web portion toward the battery pack to function as a deformation allowance in the event of a vehicle collision.

[0005] Patent Document 1 does not mention the specific mounting shape of the flange portion relative to the battery pack, but if the flange portion is shaped to protrude horizontally from the web portion toward the battery pack, as shown in Figure 2 of Patent Document 1, there is a risk that the flange portion will not be sufficiently compressed and deformed during a vehicle collision, as it will be pushed against the side of the battery pack. In this case, the collision load is directly input from the web portion, which corresponds to the battery frame, to the battery pack via the flange portion, so there is room for improvement in order to enhance the protection performance of the battery pack.

[0006] It should be noted that the battery-side bracket in Patent Document 1 is said to function as a crushable zone in the web portion during a collision (see paragraph

[0030] of the same document), but since the basic shape of the web portion is a closed cross-sectional shape and has high rigidity, there is still room for improvement in order to efficiently absorb collision energy and improve the protective performance of the battery pack. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Patent Publication No. 2023-6072 Summary of the Invention [Problem to be solved by the invention]

[0008] This invention was made in consideration of such problems, and aims to provide a vehicle battery structure that can efficiently absorb the collision energy input from the battery frame to the connecting member during a vehicle collision, and protect the battery module from collision loads. [Means for solving the problem]

[0009] This invention comprises a battery module arranged under the floor of a vehicle, a battery frame that surrounds the battery module when the vehicle is viewed from above, and a connecting member that connects the battery frame to the battery module, and is characterized in that the connecting member has a deformation promoting portion on the battery frame side of the fixing portion with the battery module that promotes deformation in response to a collision load input from the battery frame to the battery module.

[0010] According to this configuration, when a collision load is input from the battery frame to the connecting member during a vehicle collision, the deformation promoting portion itself or its surrounding area deforms, thereby efficiently absorbing the collision energy, thereby suppressing the input of the collision load from the battery frame to the battery module and protecting the battery module from the collision load.

[0011] As an aspect of the present invention, the connecting member may include a plate-shaped bracket fixed to the battery frame, and a fixing member that fixes the bracket and the battery module at the fixing portion.

[0012] According to the above configuration, even if the connecting member is deformed by a collision load or a collision load is input to the fixing portion, the bracket and the battery module can be kept firmly fixed by the fixing member. Therefore, even in the event of a vehicle collision, the battery frame can maintain its support function for the battery module via the connecting member.

[0013] In another aspect of the present invention, the deformation promoting portion includes a vertical surface portion extending in a direction along the side surface portion of at least one of the battery module and the battery frame, a module side connecting surface portion extending from the vertical surface portion toward the battery module side, and a frame side connecting surface portion extending from the vertical surface portion toward the battery frame side, and the module side connecting surface portion and the frame side connecting surface portion may be arranged at different positions from each other in the direction along the side surface portion.

[0014] According to the above configuration, even when a vehicle collision occurs and a collision load is transmitted from the battery frame to the bracket in a direction along the module side connecting surface portion and the frame side connecting surface portion (collectively referred to as the "connecting surface portion"), the vertical surface portion is promoted to undergo bending deformation (flexing deformation) such that it falls in a direction along the connecting surface portion, with the boundary portion with the module side connecting surface portion as a fulcrum, and the collision energy can be efficiently absorbed.

[0015] In another aspect of the present invention, the deformation promoting portion may be an opening formed through the periphery including at least one of the boundary portions between the vertical surface portion and the module side connecting surface portion and the boundary portion between the vertical surface portion and the frame side connecting surface portion.

[0016] According to the above configuration, the bracket has a ridge line formed along the boundary portion, which makes the boundary portion stronger than other parts, but since such a boundary portion can be divided by the opening, the boundary portion where the ridge line is formed can be weakened.

[0017] Therefore, deformation (bending deformation) of the bracket at the boundary portion where the ridge line is formed is promoted in response to a collision load, and collision energy can be efficiently absorbed.

[0018] In another aspect of the present invention, the battery module may be provided with a flange portion that protrudes toward the vertical surface portion and is fixed to the bracket at the fixing portion, and the opening may be provided at a position corresponding to the flange portion in a direction along one of the boundary portions.

[0019] According to the above configuration, even if the bracket deforms in a direction that brings the vertical surface portion and the flange portion protruding toward the vertical surface portion closer to each other during a vehicle collision, the flange portion is inserted into the opening provided in the vertical surface portion, thereby avoiding interference with each other. Therefore, the bracket can ensure a deformation stroke and can firmly absorb collision energy.

[0020] The present invention does not exclude a configuration in which the opening is provided in a position that does not correspond to the flange portion. Also, in a configuration in which a plurality of openings and flange portions are arranged in a direction along the boundary portion, the present invention may provide at least one opening in a position that corresponds to the flange portion, or may provide all openings in positions that do not correspond to the flange portion.

[0021] In another aspect of the present invention, the bracket may be provided with a connecting surface portion extending along the direction connecting the battery frame and the battery module, and the deformation promoting portion may be provided with a bead that protrudes to the other side in the vertical direction (thickness direction of the connecting surface portion) of the connecting surface portion so that one side is concave.

[0022] According to this configuration, when a vehicle crashes, the bead acts as a breakage trigger for the connecting surface portion, accelerating deformation (bending deformation) of the connecting surface portion, thereby enabling collision energy to be absorbed efficiently.

[0023] The bead may be either an upwardly protruding shape or a downwardly protruding shape, and when multiple beads are arranged on the connecting surface portion, the connecting surface portion may be configured to have both an upwardly protruding bead and a downwardly protruding bead.

[0024] In another aspect of the present invention, the battery module may be provided with a flange portion that protrudes toward the battery frame and is positioned from above relative to the connecting surface portion at the fixing portion, and the bead may protrude downward in the vertical direction relative to the connecting surface portion on the opposite side to the side on which the flange portion is positioned.

[0025] According to this configuration, even if the connecting surface portion is deformed in the connecting direction due to a vehicle collision, the bead and the flange portion can be prevented from interfering with each other in a tensioning manner. Therefore, the bracket can ensure a deformation stroke during a vehicle collision, and as a result, can firmly absorb the collision energy.

[0026] As another aspect of the present invention, the end of the bracket on the side of the battery module may include a module-facing surface portion whose surface faces a side surface portion of the battery module.

[0027] According to the above configuration, even if the end of the bracket on the side of the battery module abuts against the side portion of the battery module during a vehicle collision, the module-facing surface portion provided on the end abuts against the side portion of the battery module, thereby increasing the effect of dispersing the collision load input to the battery module side. The module-facing surface portion may face the side surface portion of the battery module in a state of abutting against the side surface portion, or may face the side surface portion with a gap therebetween.

[0028] In another aspect of the present invention, the end of the bracket on the battery frame side may have a frame opposing surface portion whose surface faces the side surface portion of the battery frame, and the frame opposing surface portion may be fixed to the side surface portion of the battery frame. According to the above configuration, the frame-facing surface portion of the bracket is fixed in surface contact with the side surface portion of the battery frame, thereby increasing the support rigidity of the battery module. [Effects of the Invention]

[0029] According to the present invention, it is possible to provide a vehicle battery structure that can protect the battery module against a collision load in the event of a vehicle collision. [Brief explanation of the drawings]

[0030] [Figure 1] FIG. 1 is an external perspective view showing a battery structure of a vehicle according to an embodiment of the present invention, as viewed from above and in front of the vehicle; [Figure 2] FIG. 1 is a plan view showing the appearance of the battery unit with the lid removed; [Figure 3] Enlarged cross-sectional view of the main part taken along the line AA in Figure 2 [Figure 4] 3 is an enlarged perspective view showing the main part, partly in phantom lines, as seen from above and behind the arrow A'-A' in FIG. 2; [Figure 5] FIG. 4 is an enlarged cross-sectional view of a main part corresponding to FIG. 3 and showing the behavior of the connecting member during a vehicle collision. [Figure 6]4A is an enlarged cross-sectional view of a main part of FIG. 3 showing a first modified example of the connecting member shown in FIG. 3, and FIG. 4B is an enlarged perspective view of the main part of the connecting member shown in FIG. [Figure 7] 3A is an enlarged perspective view of a main part of a second modified example of the connecting member shown in FIG. 3, corresponding to FIG. 4, and FIG. 3B is an enlarged perspective view of a main part of a third modified example of the connecting member shown in FIG. 3; DETAILED DESCRIPTION OF THE INVENTION

[0031] An embodiment of the present invention will be described in detail below with reference to the drawings. In the drawings, arrow Y indicates the fore-and-aft direction of the vehicle body, arrow W indicates the width direction of the vehicle, and arrow Z indicates the up-and-down direction. Furthermore, arrow Yf indicates the front of the vehicle, arrow Yr indicates the rear of the vehicle, arrow Wr indicates the right side of the vehicle, arrow Wl indicates the left side of the vehicle, arrow Zu indicates the top of the vehicle, and arrow Zd indicates the bottom of the vehicle. Furthermore, in the following description, unless otherwise specified, the front, rear, left, right, up, and down directions respectively indicate the front, rear, left, right, up, and down directions of the vehicle body, and each of the above directions of the vehicle body is based on a passenger seated in the driver's seat.

[0032] 1, the vehicle 1 of this embodiment is an electrically powered vehicle, such as an electric vehicle or a hybrid vehicle, that is equipped with at least a motor as a power source. A battery unit 10 is disposed below a floor panel 90 that forms the floor surface of the vehicle 1, and supplies and receives power to and from the driving motor.

[0033] The battery unit 10 includes a battery module 11 (see FIG. 2) and a battery case 20. The battery module 11 is a rectangular parallelepiped battery assembly in which a plurality of rectangular parallelepiped battery cells (battery elements) having a standard voltage are arranged in a stacked configuration. The battery cells in this embodiment are, for example, lithium ion batteries, which are a type of secondary battery, but other secondary batteries such as whole solid-state batteries may also be used.

[0034] 2, the battery module 11 is housed inside a battery case 20. In this example, the battery case 20 has a generally rectangular parallelepiped shape that is flat in the vertical direction of the vehicle. By providing the battery case 20 in substantially the entire lower area of ​​the floor panel 90, it is possible to mount a large-capacity battery in the vehicle 1.

[0035] 1 and 2, the battery case 20 is made of metal and includes a battery frame 21, a bottom plate 12 (see FIG. 2), a lid 13 (see FIG. 1), and a connecting member 40 (see FIG. 2). Fig. 2 shows a plan view of the battery case 20 with the lid 13 removed.

[0036] 2, the battery frame 21 has a pair of vertical frames 22 and a pair of horizontal frames 31, and is configured as a rectangular frame that is long in the front-to-rear direction relative to the vehicle width direction and that covers the entire periphery of the battery, i.e., the battery module 11, in a plan view of the vehicle so as to be retractable. The battery frame 21 also supports the battery module 11 via connecting members 40 and the like.

[0037] The pair of vertical frames 22 face each other at a distance in the vehicle width direction on both sides of the battery frame 21 in the vehicle width direction, and extend linearly along the front-to-rear direction. The pair of horizontal frames 31 face each other at a distance in the vehicle width direction on both sides of the battery frame 21 in the vehicle width direction, and extend linearly along the vehicle width direction. The pair of vertical frames 22 are formed to have the same length, and the pair of horizontal frames 31 are formed to have the same length, but the vertical frames 22 are formed to be longer than the horizontal frames 31.

[0038] The vertical frame 22 is an extruded member made of metal, for example, an aluminum alloy, and has a plurality of parallel closed cross-sectional portions 22a penetrating the interior in the longitudinal direction (front-rear direction) as shown in Fig. 3. The closed cross-sectional portions 22a are formed when the vertical frame 22 is manufactured by extrusion molding, and by giving the vertical frame 22 such a closed cross-sectional structure, the rigidity against a side impact load (a collision load input to the vehicle from the side) is increased.

[0039] The horizontal frames 31 are made of metal, for example, aluminum alloy castings. Because the horizontal frames 31 are made of aluminum alloy castings, which have a high degree of freedom in shape, they are configured to have higher torsional rigidity than the vertical frames 22 when the vehicle 1 is running, for example, by providing a plurality of reinforcing ribs (not shown) in the vertical and transverse directions.

[0040] The pair of vertical frames 22 are both rectangular in shape with the up-down direction longer than the vehicle width direction so that their orthogonal cross sections perpendicular to the longitudinal direction (front-to-rear direction) are L-shaped or inverted L-shaped. The pair of horizontal frames 31 are both rectangular in shape with the up-down direction longer than the front-to-rear direction in their orthogonal cross sections perpendicular to the longitudinal direction (front-to-rear direction). The pair of vertical frames 22 and the pair of horizontal frames 31 have the same length (height) in the up-to-down direction.

[0041] 2, in the battery frame 21, at the four corners of the vehicle in a plan view, longitudinal ends 22t of the vertical frames 22 are fastened to longitudinal ends 31t of the corresponding horizontal frames 31 in the longitudinal direction of the horizontal frames 31 using bolts (not shown) as fastening means. As a result, the battery frame 21 is integrally formed into a frame shape in a plan view by the pair of vertical frames 22 and the pair of horizontal frames 31.

[0042] 1, the battery frame 21 configured as described above has the front horizontal frame 31 fastened to left and right torque boxes 91 (only the left side of the vehicle is shown) under the floor of the vehicle 1. Furthermore, the left and right vertical frames 22 are fastened to the corresponding left and right side sills 92. Furthermore, the battery frame 21 has the rear horizontal frame 31 connected to a floor cross member (also referred to as the "No. 4 cross member") 93.

[0043] The above-described side sills 92, torque boxes 91, and floor cross members 93 are all body frame members that form the body frame of the vehicle 1. Supplementally, a pair of left and right torque boxes 91 are provided in front of the battery module 11 to connect the front side frames 94 and the side sills 92 in the vehicle width direction, and each torque box 91 has a closed cross-sectional portion that extends in the vehicle width direction.

[0044] A pair of side sills 92 are provided on the left and right ends of the floor panel 90, each having a closed cross-section extending in the fore-and-aft direction of the vehicle. Furthermore, the floor cross member 93 has a closed cross-section extending in the vehicle width direction at the rear end of the floor panel 90 so as to connect the left and right rear side frames 95 in the vehicle width direction. The battery frame 21 is fixed to a vehicle body frame member, and the battery module 11 is supported by the vehicle body via the battery frame 21.

[0045] 2, the bottom plate 12 covers the battery modules 11 housed inside the battery case 20 from below so as to form the bottom surface of the battery case 20. Furthermore, the bottom plate 12 extends substantially horizontally, including the area on the inner side (center side) of the battery frame 21, which has a rectangular shape in plan view, and the area directly below the battery frame 21, and is fixed to the lower surfaces of the pair of vertical frames 22 and the pair of horizontal frames 31 that constitute the battery frame 21.

[0046] 1 , the lid 13 covers the battery module 11 housed inside the battery case 20 from above so as to form the upper surface of the battery case 20. Furthermore, the lid 13 includes an area inside the battery frame 21, which has a rectangular shape in a plan view, and an area directly above the battery frame 21, and is fixed to the upper surfaces of the pair of vertical frames 22 and the pair of horizontal frames 31 that make up the battery frame 21.

[0047] The battery case 20 defines an internal storage space 20s for the battery module 11 by the battery frame 21 having a rectangular shape in plan view, the bottom plate 12, and the lid 13 (see FIG. 2). In this embodiment, the bottom plate 12 and the lid 13 are fixed to the battery frame 21 by bolting, but this is not limiting and other fixing means such as welding may also be used.

[0048] As shown in FIG. 2, the interior (accommodation space 20s) of the battery case 20 is provided with reinforcing members, such as lateral reinforcing members 14 extending in the vehicle width direction and vertical reinforcing members 15 extending in the front-rear direction. In this example, three lateral reinforcing members 14 are provided in the storage space 20s, and are arranged at intervals in the front-rear direction so as to divide the storage space 20s into approximately four equal parts in the front-rear direction. Furthermore, each lateral reinforcing member 14 extends over the entire length of the storage space 20s in the vehicle width direction until both end portions reach the left and right vertical frames 22, and each lateral reinforcing member 14 stands upright like a vertical wall from the bottom plate 12 at a height slightly lower than that of the battery frame 21.

[0049] One vertical reinforcing member 15 is provided in each storage space 20s, and is disposed at a middle position in the vehicle width direction of the storage space 20s so as to divide the storage space 20s into approximately two equal parts in the vehicle width direction. Furthermore, the vertical reinforcing member 15 extends over the entire length of the storage space 20s in the front-rear direction, with both ends reaching the front and rear cross frames 31, and stands upright like a vertical wall from the bottom plate 12 at a height slightly lower than that of the battery frame 21.

[0050] 2, the storage space 20s is divided into eight spaces approximately equally by the horizontal reinforcing members 14 and the vertical reinforcing members 15 in a plan view of the vehicle, and in each area the battery modules 11 are arranged in the vicinity of the battery frame 21, the horizontal reinforcing members 14, and the vertical reinforcing members 15. For example, the inner side surface (inner surface) of the battery frame 21 in a plan view of the vehicle and the side surface portion 36 of the horizontal frame 31 that directly faces the inner surface face each other, face each other with a small gap in between.

[0051] 2, in this example, the connecting members 40 are arranged along the left and right sides of the front and rear horizontal frames 31 in the storage space 20s of the battery frame 21, and a total of four connecting members 40 are provided throughout the battery case 20. The battery modules 11 arranged near the front and rear horizontal frames 31 are supported by the horizontal frames 31 via the connecting members 40 provided between these battery modules 11 and the horizontal frames 31.

[0052] The four connecting members 40 described above are formed to have the same shape. Therefore, the specific shape of the connecting members 40 will be described below based on the connecting member 40 on the front left side in a plan view of the vehicle, which is shown in the cross-sectional view taken along line AA in FIG. However, in the following description, of the mutually opposing side portions 16, 36 of the battery module 11 and the horizontal frame 31 shown in Figure 3, the side portion 16 of the battery module 11 will be referred to as the module side portion 16, and the side portion 36 of the horizontal frame 31 will be referred to as the frame side portion 36.

[0053] 3 and 4, a flange portion 17 serving as an attachment piece for attaching the connecting member 40 to the battery module 11 is provided on the module side surface portion 16 (see FIG. 3) and protrudes toward the frame side surface portion 36 of the horizontal frame 31 (i.e., toward the front). The flange portion 17 is formed in a flat plate shape having a thickness in the vertical direction, and as shown in FIG. 3, a bolt insertion hole 17a is formed in the thickness direction (i.e., the vertical direction) through which a bolt 60B (described later) for fastening to the bracket 41 can be inserted. As shown in FIG. 2, a plurality of flange portions 17 (three in this example) are arranged at intervals from each other in the vehicle width direction of one connecting member 40.

[0054] The connecting member 40 includes a plate-shaped bracket 41 fixed to the horizontal frame 31, and fastening means as a fixing member for fixing the bracket 41 and the battery module 11, which in this example includes a bolt 60B and a nut 60N.

[0055] The bracket 41 is formed in the shape of a plate that has been plastically deformed into a desired shape (described later) by press forming or the like from a metal plate material. The bracket 41 includes a connecting surface 42, a frame-facing surface 43, and a module-facing surface 44.

[0056] The connecting surface portion 42 is provided with a vertical surface portion 45, a module-side connecting surface portion 46, and a frame-side connecting surface portion 47, which are arranged between the frame-facing surface portion 43 and the module-facing surface portion 44 so as to be able to connect these. The vertical surface portion 45 is formed in the shape of a flat plate and is arranged between the frame-facing surface portion 43 and the module-facing surface portion 44 so as to extend in the up-down direction.

[0057] The frame side connecting surface portion 47 is formed in a flat plate shape extending from the upper end of the vertical surface portion 45 toward the battery frame 21 side, and its front end is formed integrally with the frame opposing surface portion 43 so as to connect to the frame opposing surface portion 43.

[0058] The module side connecting surface portion 46 is formed in a flat plate shape extending from the lower end of the vertical surface portion 45 toward the battery module 11 side, and its rear end is formed integrally with the module opposing surface portion 44 so as to connect to the module opposing surface portion 44.

[0059] As a result, as shown in Figure 3, the module side connecting surface portion 46 and the frame side connecting surface portion 47 are arranged at different heights in the vertical direction (the frame side connecting surface portion 47 is at a higher position than the module side connecting surface portion 46), and are arranged separately from each other on one side (rear side) and the other side (front side) of the vertical surface portion 45, but are connected to each other via the vertical surface portion 45, and are formed as a whole in a crank shape (step shape) when viewed from the side of the vehicle.

[0060] In this example, the module-side connecting surface portion 46 and the frame-side connecting surface portion 47 are arranged horizontally and parallel to each other, with both having a thickness in the up-down direction. The vertical surface portion 45 is arranged perpendicular (at right angles) to the module-side connecting surface portion 46 and the frame-side connecting surface portion 47 in a side view of the vehicle, with a thickness in the front-rear direction.

[0061] The frame-facing surface portion 43 is provided at the end of the bracket 41 on the battery frame 21 side so as to face the frame side surface portion 36. More specifically, the frame-facing surface portion 43 hangs down from the end of the frame-side connecting surface portion 47 on the battery frame 21 side along the frame side surface portion 36, and is arranged from the rear side so that their surfaces abut against the frame side surface portion 36. In this example, the frame-facing surface portion 43 is fixed to the frame side surface portion 36 by welding. The frame opposing surface portion 43 may be fixed to the frame side surface portion 36 by other fixing means such as fastening with a fastening member, instead of by welding.

[0062] 3, the module-facing surface portion 44 is provided at the end of the bracket 41 on the battery module 11 side so as to face the module side surface portion 16. More specifically, the module-facing surface portion 44 hangs down from the end of the module-side connecting surface portion 46 on the battery module 11 side along the module side surface portion 16, and is disposed so that the surfaces of the module-facing surface portion 44 face each other with a gap between them in the front-to-rear direction.

[0063] In this example, the frame-facing surface portion 43 and the module-facing surface portion 44 are arranged parallel to the vertical surface portion 45, which is vertically arranged and has a thickness in the front-rear direction. Furthermore, the connecting surface portion 42, the frame-facing surface portion 43, and the module-facing surface portion 44 are formed to have the same bracket width (length in the vehicle width direction).

[0064] As shown in Figures 3 and 4, the above-mentioned bracket 41, in other words, has a fixing portion 48 for connection with the flange portion 17 of the battery module 11, and has a first deformation promoting portion 50 on the battery frame 21 side of the fixing portion 48, and an opening 51 (see Figure 4) as a second deformation promoting portion.

[0065] The fixing portion 48 is a fixing portion for fixing to the flange portion 17 of the battery module 11, and is provided with a bolt insertion hole 48a that penetrates the module side connecting surface portion 46 in the thickness direction (i.e., the up-down direction) of the module side connecting surface portion 46 along the front-to-rear direction.

[0066] The bracket 41 is fastened to the flange portion 17 of the battery module 11, which is disposed on the upper surface of the fixing portion 48 of the module-side connecting surface portion 46, by a bolt 60B and a nut 60N as fixing members.

[0067] Specifically, as shown in FIG. 3, when the bracket 41 is fastened to the flange portion 17 at the fixing portion 48, the bolt insertion holes 17a, 48a formed in the flange portion 17 and the fixing portion 48 arranged below the flange portion 17 are vertically connected to each other. The bolt 60B is inserted from above into the bolt insertion holes 17a, 48a, which are connected to each other in this order. Furthermore, a nut 60N is screwed from below onto the bolt 60B protruding downward from the module-side connecting surface 46. As a result, the flange portion 17 and the bracket 41 are fastened and fixed by being sandwiched from both sides between the bolt 60B and the nut 60N.

[0068] 3, when the bracket 41 is fastened to the flange 17 at the fixing portion 48, the front end 17f of the flange 17 and the vertical surface 45 located in front of the front end 17f are spaced apart from each other in the front-to-rear direction. On the other hand, the rear end of the nut 60N and the module-facing surface 44 located behind the rear end are also spaced apart from each other in the front-to-rear direction.

[0069] As shown in Figure 4, the first deformation promoting portion 50 and the second deformation promoting portion (51) are both located on the battery frame 21 side of the fixing portion 48 with the flange portion 17 of the battery module 11, and are capable of promoting deformation in response to a collision load input from the battery frame 21 to the battery module 11. In this example, the first deformation promoting portion 50 is composed of the vertical surface portion 45 and the frame side connecting surface portion 47, which are located forward of the fixing portion 48 of the module side connecting surface portion 46, which is formed in an overall crank shape when viewed from the side of the vehicle.

[0070] The above-mentioned bracket 41 is provided with a first deformation promoting portion 50, so that a space 50s is formed in front of the vertical surface portion 45, which is defined by the vertical surface portion 45, the frame side connecting surface portion 47 and the frame opposing surface portion 43 and opens downward.

[0071] As shown in Figure 4, the second deformation promoting portion (51) is an opening 51 formed through the peripheral area including the boundary 52 between the vertical surface portion 45 and the module side connecting surface portion 46, more specifically, the area from near the lower end of the vertical surface portion 45 to near the front end of the module side connecting surface portion 46.

[0072] That is, a ridge line 53 extending along the boundary 52 between the vertical surface portion 45 and the module side connecting surface portion 46 is formed, thereby increasing the rigidity of the boundary 52 and its surrounding area, and the opening 51 is arranged to divide the ridge line 53 in the vehicle width direction. In this example, multiple openings 51 are arranged along the boundary portion 52, and each opening 51 is provided in a portion that does not correspond to (does not coincide with) the flange portion 17 in the direction along the boundary portion 52 of the bracket 41 (the vehicle width direction), more specifically, between adjacent flange portions 17 (see Figure 4).

[0073] As shown in Figures 1 and 2, the battery unit 10 as the battery structure of the vehicle 1 of this embodiment comprises a battery module 11 arranged below the floor panel 90 of the vehicle, a battery frame 21 that surrounds the battery module 11 when viewed from above and supports the battery module 11, and a connecting member 40 (see Figure 2) that connects the battery frame 21 and the battery module 11, and as shown in Figures 3 and 4, the connecting member 40 has a first deformation promoting portion 50 on the battery frame 21 side of the fixing portion 48 with the battery module 11, as a deformation promoting portion that promotes deformation in response to a collision load input from the battery frame 21 to the battery module 11.

[0074] According to the above configuration, when a collision load is input from the battery frame 21 to the connecting member 40 during a vehicle collision, the battery frame 21 approaches the battery module 11, causing the first deformation promoting portions 50 of the connecting member 40 to deform so as to be compressed (crushed), as shown in Fig. 5, for example, and the collision energy can be efficiently absorbed. This suppresses the input of the collision load from the battery frame 21 to the battery module 11, and protects the battery module 11 against the collision load.

[0075] In one embodiment of the present invention, as shown in Figures 3 and 4, the connecting member 40 includes a plate-shaped bracket 41 fixed to the battery frame 21, and a bolt 60B and a nut 60N as fixing members that fix the bracket 41 and the battery module 11 at the fixing portion 48.

[0076] According to the above configuration, for example, even if the connecting member 40 is deformed by a collision load or the collision load is input to the fixing portion 48, the bracket 41 and the battery module 11 can be kept firmly fixed together by the bolt 60B and the nut 60N. Therefore, the support function of the battery frame 21 for the battery module 11 via the connecting member 40 can be improved.

[0077] In one embodiment of the present invention, as shown in FIG. 3, the first deformation promoting portion 50 is composed of a vertical surface portion 45 extending in the vertical direction along the module side surface portion 16 and the frame side surface portion 36, a module side connecting surface portion 46 extending horizontally from the vertical surface portion 45 toward the battery module 11 side, and a frame side connecting surface portion 47 extending horizontally from the vertical surface portion 45 toward the battery frame 21 side, and the module side connecting surface portion 46 and the frame side connecting surface portion 47 are positioned at different heights in the vertical direction.

[0078] According to the above configuration, when a collision load is transmitted from the battery frame 21 along the frame side connecting surface 47 of the bracket 41, a moment load acts on the vertical surface 45 with the boundary 52 with the module side connecting surface 46 as a fulcrum, as shown in FIG. 5, which promotes bending deformation (flexural deformation) such that the vertical surface 45 falls sideways along the horizontal direction, and as a result, the collision energy can be efficiently absorbed.

[0079] In one embodiment of the present invention, as shown in Figure 4, the deformation promoting portion further includes an opening 51 as a second deformation promoting portion that penetrates the peripheral portion including the boundary portion 52 between the vertical surface portion 45 and the frame side connecting surface portion 47.

[0080] According to the above configuration, the bracket 41 has a ridge line 53 formed thereon that extends along the boundary portion 52, so that the boundary portion 52 is stronger than other parts, but because the boundary portion 52 can be divided by the opening 51, the boundary portion 52 where the ridge line 53 is formed can be weakened. Therefore, as shown in FIG. 5, deformation (bending deformation) of the bracket 41 at the boundary portion 52 where the ridge line 53 is formed is promoted in response to the collision load, and the bracket 41 can efficiently absorb the collision energy.

[0081] The opening as the second deformation promoting portion is not limited to opening 51 (also referred to as "lower opening 51") in this example, but may be upper opening 51A (also referred to as "opening 51A") that is formed by penetrating the periphery including boundary 52A between frame-side connecting surface 47 and vertical surface 45, as shown by the imaginary line in Fig. 4. That is, the second deformation promoting portion may be provided with at least one of upper opening 51A and lower opening 51, for example, by providing both upper opening 51A and lower opening 51.

[0082] In one embodiment of the present invention, as shown in Figures 3 and 4, the end of the module side connecting surface portion 46 of the bracket 41 on the battery module 11 side is provided with a module opposing surface portion 44 whose surfaces face the module side surface portion 16 with a gap therebetween.

[0083] According to the above configuration, even if the fixing portion 48 breaks during a vehicle collision, and the end of the bracket 41 on the battery module 11 side abuts against the module side portion 16, the module-facing surface portion 44 provided at the end abuts against the module side portion 16, as shown by the virtual line in Figure 5, thereby increasing the effect of dispersing the collision load input from the bracket 41 to the battery module 11.

[0084] In this example, the module opposing surface portion 44 faces the module side surface portion 16 at a distance in the longitudinal direction in the shape before the vehicle collision (before the bracket 41 is deformed); however, the module opposing surface portion of the present invention may face the module side surface portion 16 with their surfaces abutting in the shape before the vehicle collision, as long as the effect of dispersing the collision load input to the battery module 11 during a vehicle collision can be increased by having the surface abut against the module side surface portion 16.

[0085] In one embodiment of the present invention, as shown in Figures 3 and 4, the end of the bracket 41 on the battery frame 21 side has a frame opposing surface portion 43 whose surface faces the frame side surface portion 36, and the frame opposing surface portion 43 is fixed to the frame side surface portion 36. According to the above configuration, the bracket 41 is fixed with the frame facing surface portion 43 in surface contact with the frame side surface portion 36, so that the support rigidity of the battery module 11 can be increased.

[0086] In correspondence between the configuration of this invention and the above-mentioned embodiment, The underfloor of the vehicle corresponds to the underside of the floor panel 90 of the vehicle, and so on. The deformation promoting portion corresponds to at least the first deformation promoting portion 50 out of the first deformation promoting portion 50 and the second deformation promoting portion 51; The fixing member corresponds to the bolt 60B and the nut 60N. The openings correspond to the opening 51 and / or the upper opening 51A, but the present invention is not limited to the configurations of the above-described embodiments, and many other embodiments can be obtained.

[0087] For example, as in a bracket 41A of Modification 1 shown in FIGS. 6(a) and 6(b), the deformation promoting portion may include a bead 71 that protrudes downward so that the upper surface of the connecting surface portion 42A has a concave shape. Specifically, bracket 41A of modified example 1 does not have connecting surface portion 42A equipped with vertical surface portion 45 as in the above-described embodiment, but rather has connecting surface portion 42A in which module-side connecting surface portion 46 and frame-side connecting surface portion 47 are formed to be continuous with each other in a substantially horizontal manner. Such connecting surface portion 42A is provided with bead 71 as another deformation promoting portion different from the above-described first deformation promoting portion 50. In this example, bead 71 is formed continuously over the entire length of connecting surface portion 42A in the vehicle width direction (bracket width direction).

[0088] According to the above configuration, the downwardly protruding bead 71 provided on the connecting surface portion 42A is crushed in the front-rear direction as shown by the imaginary lines in Fig. 6(a) during a vehicle collision, which triggers the breaking of the connecting surface portion 42A. As a result, although the connecting surface portion 42A is horizontal along the front-rear direction, deformation (bending deformation) that compresses the connecting surface portion 42A in the front-rear direction without being stretched in the front-rear direction during a vehicle collision is promoted, resulting in efficient absorption of collision energy.

[0089] Furthermore, the bead of the present invention may have a shape that protrudes either upward or downward, but it is preferable that it protrudes downward, opposite to the upper side where the flange portion 17 is located relative to the connecting surface portion 42A, as in the bead 71 of the above-mentioned variant example 1.

[0090] This configuration makes it possible to avoid locating the upwardly protruding bead 71 immediately before the tip 17f (front end) of the flange portion 17, and therefore, when the connecting surface portion 42A is deformed and crushed in the connecting direction due to a vehicle collision, it is possible to avoid interference between the upwardly protruding bead 71 and the flange portion 17. Therefore, the bracket 41 can ensure a deformation stroke during a vehicle collision and can firmly absorb the collision energy.

[0091] Furthermore, the beads of the present invention are not limited to being formed continuously over the entire length in the vehicle width direction, as in the bead 71 of the above-mentioned variant example 1, but may be arranged in multiple positions spaced apart from each other in the vehicle width direction, as in the bead 71A shown in Figure 7(a).

[0092] Furthermore, the opening as the second deformation promoting portion is provided in a position that does not correspond to the flange portion 17 in the direction along the boundary portion 52, like the opening 51 in the bracket 41 of the above-described embodiment, but is not limited to this, and may be provided in a position that corresponds to the flange portion 17, i.e., a matching position, in the direction along the boundary portion 52, like the opening 51B in the bracket 41B of modified example 2 shown in Figure 7(b).

[0093] According to the above configuration, even when a vehicle collision occurs, for example, when the fixing portion 48 breaks and the vertical surface portion 45 of the bracket 41B and the flange portion 17 protruding toward the vertical surface portion 45 are compressed and deformed in the fore-and-aft direction so as to come into excessively close proximity, the flange portion 17 is displaced so as to be inserted into the opening 51 provided in the vertical surface portion 45, thereby suppressing interference between the flange portion 17 and the vertical surface portion 45.

[0094] As a result, in the event of a vehicle collision, bracket 41B can firmly absorb collision energy without being hindered from smooth deformation due to interference between vertical surface portion 45 and flange portion 17 that stretches in the front-to-rear direction. That is, opening 51B not only functions to weaken boundary portion 52 that forms ridge line 53, but also functions as a relief portion that avoids interference between vertical surface portion 45 and flange portion 17 in the event of a vehicle collision.

[0095] In addition, in a configuration in which multiple flange portions 17 are arranged along the vehicle width direction, the multiple openings may be arranged in a direction along the boundary portion 52, as described above, so that they correspond to each of all of the flange portions 17, or so that they are offset so that they do not correspond, or a mixture of aligned and offset openings may be used.

[0096] Furthermore, in this example and the above-mentioned variant example 2, an example has been described in which the first deformation promoting portion 50 and openings 51, 51A, 51B are provided as the second deformation promoting portion, but the present invention may also be configured to have only the first deformation promoting portion 50 without providing openings 51, 51A, 51B as the second deformation promoting portion.

[0097] Furthermore, in the above-described embodiment, the connecting member 40 is provided between the battery module 11 and the horizontal frame 31 so as to be able to connect them, but the connecting member of the present invention is not limited to this and may also be provided between the vertical frame 22 and the battery module 11 so as to be able to connect them, in which case, when the vehicle is hit in a side collision, the side collision energy can be efficiently absorbed by the deformation of the deformation promoting portion. [Explanation of symbols]

[0098] 10...Battery unit (vehicle battery structure) 11...Battery module 17...Flange 16...Module side portion (side portion of battery module) 21...Battery frame 36...Frame side portion (side portion of battery frame) 40, 40A, 40B...Connecting members 41, 41A, 41B...Bracket 42,42A…Connection surface part 45...Vertical section 46...Module side connection surface 47...Frame side connection surface part 48…Fixed part 50...First deformation promoting portion (deformation promoting portion) 51, 51A, 51B... Openings as second deformation promoting portions (deformation promoting portions) 52...Boundary between vertical surface and module side connecting surface 52A...Boundary between vertical surface and frame side connecting surface 60B...Bolt (fixing member) 60N...Nut (fixing member) 71...Bead (deformation promoting part) 90...Floor panel Y: Front-rear direction (direction connecting the battery frame and battery module) Zu: upward direction (direction along the side surface of at least one of the battery module and the battery frame)

Claims

1. a battery module disposed under the floor of the vehicle; a battery frame that covers the periphery of the battery module in a plan view of the vehicle; a connecting member that connects the battery frame and the battery module, The connecting member is located closer to the battery frame than the fixed portion with the battery module, a deformation promoting portion that promotes deformation of the battery module in response to a collision load input from the battery frame to the battery module; Vehicle battery structure.

2. The connecting member includes a plate-shaped bracket fixed to the battery frame, and a fixing member that fixes the bracket and the battery module at the fixing portion. The vehicle battery structure according to claim 1 .

3. The deformation promoting portion is a vertical surface portion extending in a direction along a side surface portion of at least one of the battery module and the battery frame; The battery module has a module-side connecting surface portion extending from the vertical surface portion toward the battery module side, and a frame-side connecting surface portion extending from the vertical surface portion toward the battery frame side, and the module-side connecting surface portion and the frame-side connecting surface portion are disposed at different positions from each other in the direction along the side surface portion. The vehicle battery structure according to claim 2 .

4. The deformation promoting portion is The opening is formed so as to penetrate a periphery including at least one of the boundary between the vertical surface portion and the module-side connecting surface portion and the boundary between the vertical surface portion and the frame-side connecting surface portion.

4. The vehicle battery structure according to claim 3.

5. the battery module includes a flange portion that protrudes toward the vertical surface portion and is fixed to the bracket at the fixing portion, The opening is provided at a position corresponding to the flange portion in a direction along the one boundary portion.

5. The vehicle battery structure according to claim 4.

6. The bracket is provided with a connecting surface portion extending along a direction in which the battery frame and the battery module are connected, The deformation promoting portion has a bead that protrudes to one side in the up-down direction of the connecting surface portion so as to be concave on the other side. The vehicle battery structure according to claim 2 .

7. the battery module includes a flange portion that protrudes toward the battery frame and is disposed above the connecting surface portion in the fixing portion, The bead protrudes downward from the connecting surface portion on a side opposite to the side on which the flange portion is disposed in the up-down direction.

7. The vehicle battery structure according to claim 6.

8. The end of the bracket on the side of the battery module is provided with a module-facing surface portion whose surface faces a side surface portion of the battery module. The vehicle battery structure according to claim 2 .

9. The end of the bracket on the battery frame side is The battery frame has a frame opposing surface portion that faces the side surface portion of the battery frame, and the frame opposing surface portion is fixed to the side surface portion of the battery frame. The vehicle battery structure according to claim 2 .

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