WO2023170746A1

WO2023170746A1 - Battery attachment structure

Info

Publication number: WO2023170746A1
Application number: PCT/JP2022/009743
Authority: WO
Inventors: 征弘池田; 秀紀竹内; 稔泰平井
Original assignee: 三菱自動車工業株式会社
Priority date: 2022-03-07
Filing date: 2022-03-07
Publication date: 2023-09-14
Also published as: JPWO2023170746A1; JP7201138B1

Abstract

This battery attachment structure comprises a battery tray (41) that is secured to a floor panel (4) so as to close from below an opening (4A) formed in the floor panel (4) between cross members (5, 6) on the floor panel (4), and is able to accommodate a portion of the a battery case (30) in an internal space of the battery tray (41) that is lower than the opening (4A). The battery tray (41) has: a tray body (42) that protrudes farther downward than the opening (4A); a tray flange section (43) that is formed by bending around the entire outer periphery of the upper edge portion of the tray body (42), and that is secured by welding to an opening edge portion (4B) around the opening (4A); and a bead-shaped curved section (44) that is formed between the tray body (42) and the tray flange section (43), and that is built up above flange sections (53, 63) of the cross members (5, 6) in a state of being secured to the floor panel (4). A seal member (45) is mounted between the opening edge portion (4B) and the tray flange section (43).

Description

Battery mounting structure

This case relates to the mounting structure of a battery mounted on a vehicle.

In electric vehicles (EVs), hybrid electric vehicles (HEVs), and plug-in hybrid electric vehicles (PHEVs) that can be recharged or powered externally, the electric motor as the drive source A running battery (also referred to as an "EV battery" or simply "battery") that supplies power to the vehicle is essential. Since this battery has a large weight and a large volume, when the battery is disposed on the floor of a vehicle, it is necessary to devise a structure to ensure the rigidity of the floor. It is also required that the battery be installed in a manner that ensures waterproofness.

For example, Patent Document 1 discloses a structure in which a battery is placed directly under the rear seat. In this structure, an opening is formed in the rear floor panel directly below the rear seat, and a box (battery tray) that makes up the battery case is fixed to this opening so as to protrude below the rear floor panel. A battery is housed in the battery via a battery support member. Note that the space between the box body and the periphery of the opening is closed with a sealing member, and the space between the box body and a lid member covering the upper opening of the box body is also closed with a sealing member. With such a structure, the battery storage space inside the box is separated from the outside by the box, and it is said that it is possible to suppress the influence of external heat on the battery.

Japanese Patent Application Publication No. 2014-144775

By the way, in the structure described in Patent Document 1, the space between the box body (battery tray) and the opening of the floor panel is closed with a sealing member, and the waterproof property of the battery is taken into consideration. There is room for further improvement. There is also room for improvement from the viewpoint of ensuring rigidity.

The present invention was devised to solve the above-mentioned problems, and one of the purposes is to provide a battery mounting part structure that improves the waterproofness of the battery while increasing the shape rigidity. In addition, this purpose is not limited to this purpose, and it is also possible to achieve effects derived from each configuration shown in "Details for Carrying Out the Invention" that will be described later, which cannot be obtained with conventional techniques. It is a purpose.

The disclosed battery attachment structure can be realized as the embodiments or application examples disclosed below, and solves at least part of the above problems.
The disclosed battery mounting structure includes a floor panel of a vehicle, two cross members arranged spaced apart from each other in the front and back on the floor panel, and a structure formed between the two cross members on the floor panel. and a battery tray fixed to the floor panel so as to close the opening from below, and a battery pack is stored in an internal space located below the opening of the battery tray. This is a battery mounting part structure that can accommodate a part of the battery case.

The battery tray includes a tray body that protrudes below the opening when fixed to the floor panel, and a tray body that is bent over the entire outer periphery of the upper edge of the tray body, and has a tray body that is bent around the entire outer periphery of the upper edge of the tray body, a tray flange portion welded and fixed to the opening edge of the tray; and a bead-like curve formed between the tray body and the tray flange portion and raised above the tray flange portion when fixed to the floor panel. It has a section and.
A sealing material is installed between the opening edge of the floor panel and the tray flange.

According to the disclosed battery attachment structure, the bead-shaped curved portion becomes a reinforcing structure that compensates for the decrease in rigidity and strength around the opening of the floor panel. In addition, the bead-shaped curved part makes it easy for liquid sealant to accumulate, and if water enters from the seal between the opening edge of the floor panel and the tray flange, it prevents water from entering the tray body. It also functions as a weir to suppress it. Therefore, the waterproofness of the battery can be improved while increasing the shape rigidity.
Therefore, waterproofness is improved.

FIG. 2 is a cross-sectional view of a main part (a cross-sectional view taken along the line AA in FIG. 2) showing the structure of the battery attachment part according to the embodiment, with sheets omitted. FIG. 2 is a plan view of the main parts inside the vehicle interior showing the structure of the battery attachment part of FIG. 1, with seats omitted. FIG. 2 is a perspective view of the main parts inside the vehicle interior, showing the structure of the battery attachment part of FIG. 1. FIG. FIG. 2 is a perspective view of a battery tray according to the battery attachment structure of FIG. 1; FIG. 2 is a perspective view showing the structure of the upper part of the floor panel related to the battery attachment structure of FIG. 1; FIG. 2 is a cross-sectional view of a main part showing a portion where a tray flange portion of a battery tray according to the battery attachment structure of FIG. 1 is welded and fixed to a floor panel. 7 is a partially enlarged view of a welded and fixed portion of the tray flange portion of FIG. 6, with the sealing material omitted; FIG.

A battery attachment structure as an embodiment will be described with reference to the drawings. The embodiments shown below are merely illustrative, and there is no intention to exclude the application of various modifications and techniques not specified in the embodiments below. The configuration of each embodiment can be modified and implemented in various ways without departing from the spirit thereof. Further, they can be selected or combined as necessary.

In the following description, the forward direction of the vehicle is referred to as the front (vehicle front), left and right are defined with the front as a reference, and the left and right direction of the vehicle is also referred to as the vehicle width direction. Further, in the figure, arrow UP indicates upward, arrow FR indicates forward, arrow LH indicates left direction, and arrow RH indicates right direction.
The battery attachment structure described in detail below is a structure related to an attachment part that ensures waterproofness of a driving battery disposed on the floor of a vehicle. First, the configuration of the vehicle will be explained, and then the attachment structure will be explained in detail.

[1. composition]
As shown in FIGS. 1 to 3, a pair of left and right seats 2 (a right-hand seat 2A and a left-hand seat 2B) are installed in a vehicle interior 1. The driving battery 3 is arranged in a battery mounting space (hereinafter also simply referred to as "mounting space") provided below these seats 2. In addition, in this embodiment, the case where the seat 2 is a front seat is illustrated, but the seat 2 may be a second row seat or a third row seat.

As shown in FIG. 1, the running battery 3 is configured by housing a running battery pack (battery module) 31, wiring (not shown), etc. inside a battery case 30. Although details are not shown in the drawings, wiring, equipment for air conditioning the driving battery pack 31, and the like are attached to the outside of the battery case 30. The battery case 30 includes an under case 32 having an opening 32a at the top, and an upper case 33 attached to the under case 32 so as to close the opening 32a of the under case 32. Note that the running battery 3 is also simply referred to as "battery 3" hereinafter.

As shown in FIGS. 2, 3, and 5, two

cross members

5 and 6 are arranged on the floor panel 4, spaced apart from each other in the front and rear. In this embodiment, the rear cross member 6 (hereinafter also referred to as "rear cross member 6") extends linearly in the width direction, whereas the front cross member 5 (hereinafter also referred to as "front cross member 6") extends linearly in the width direction. 5'') has its widthwise intermediate portion shifted forward with respect to the left and right ends so as to be separated from the rear cross member 6, and extends while being bent in the width direction in plan view.

Both the front cross member 5 and the rear cross member 6 have hat-shaped cross sections. Each

cross member

5, 6 is arranged with hat-shaped

top wall parts

51, 61 facing upward, and both flanges are bent at the lower edges of

vertical wall parts

52, 62 on both edges of the

top wall parts

51, 61. The

portions

53 and 63 are welded and fixed to the upper surface of the floor panel 4. A tunnel portion 11 and a dash panel 12 are provided in front of the front cross member 5 on the floor panel 4, and a pair of left and

right side frames

13, 13 are provided on the left and right edges of the floor panel 4. be done.

Each seat 2 is installed on a pair of left and

right seat rails

20, 20 so as to be slidable in the front-rear direction. Each of the left and

right seat rails

20, 20 of each seat 2 has a front leg portion 21 fastened and fixed to the front cross member 5, and a rear leg portion 22 (see FIG. 3) fastened and fixed to the rear cross member 6. Here, the front leg portion 21 is fastened and fixed to the front cross member 5 via the auxiliary bracket 21c.
Further, the battery case 30 is fixed to each of the

cross members

5 and 6 via a pair of left and right battery fixing brackets 7 and 7 (hereinafter referred to as "brackets 7"). Note that the opening 32a of the undercase 32 is located above the upper surfaces 51a, 61a of the

top wall portions

51, 61 of the

respective cross members

5, 6.

To further explain the fixing structure of the battery case 30, as shown in FIGS. 1 to 3, a pair of

brackets

7, 7 are coupled to the battery case 30 with an interval left and right. The battery 3 is fixed to each bracket 7 by welding, bolts, etc., and the front and rear ends of each bracket 7 are fastened and fixed to the front cross member 5 and rear cross member 6, respectively, so that the battery 3 can be fixed to the vehicle. Fixed.

The bracket 7 is formed, for example, by press-molding a sheet metal. The bracket 7 of this embodiment is formed into a hat shape when viewed from the side, as shown in FIGS. 1 and 5. The bracket 7 includes a band-shaped case fixing part 71 that extends in the longitudinal direction of the vehicle when the battery 3 is mounted on the vehicle, and

arm parts

72 and 73 that are bent downward from the front and rear edges of the case fixing part 71. ,

fastening portions

74 and 75 that are bent forward or backward and extend horizontally from the lower edges of the

respective arm portions

72 and 73. The center portions of the case fixing portion 71 and the

arm portions

72 and 73 in the width direction are formed to protrude outward (in the direction away from the battery case 30) in a bead shape, thereby increasing strength and rigidity. Note that the bead is not essential and can be omitted.

The case fixing portions 71 of the bracket 7 are fastened and fixed to the left and right sides of the upper part of the battery case 30 (for example, the upper case 33) using bolts or the like, respectively. The front fastening portion 74 of each bracket 7 is fastened and fixed to the top wall portion 51 of the front cross member 5 by bolts or the like. The rear fastening portion 75 of each bracket 7 is fastened and fixed to the auxiliary bracket 8 that is welded and fixed to the rear cross member 6, as shown in FIG.

Incidentally, an opening 4A is formed in the area between the

cross members

5 and 6 in the floor panel 4 (the area below the left and

right sheets

2A and 2B). The opening 4A is formed by cutting out a portion of the floor panel 4 that is separated by a predetermined distance or more from each of the front and

rear cross members

5, 6 and left and right side frames 13, 13, so that the opening 4A is approximately It is formed into a rectangular shape. Since the opening 4A is separated from each of the

cross members

5, 6 and the left and right side frames 13, 13 by a predetermined distance or more, the opening edge 4B adjacent to the opening 4A of the floor panel 4 is secured.

Details will be described later, but as shown in FIGS. 1 and 4, the battery tray 41 is fixed to the floor panel 4 and includes a tray body 42 that protrudes below the opening 4A, and a The tray flange portion 43 is provided with a tray flange portion 43 that is bent over the entire outer periphery (entire circumference) of the upper edge portion. The battery tray 41 is fixed to the floor panel 4 by welding and fixing the tray flange portion 43 to the opening edge 4B around the opening 4A of the floor panel 4.

Note that it is also conceivable to make a part of the floor panel 4 protrude downward without providing the opening 4A in the floor panel 4 to secure a space in which the battery 3 can be accommodated. However, it is difficult to partially protrude the floor panel 4 downward by a certain depth or more in terms of forming such as press working. On the other hand, in the case of the battery tray 41 which is a separate member, it is not difficult to process it into a shape that protrudes downward by a certain depth or more by press working or the like. Therefore, in the vehicle of this embodiment, an opening 4A is provided in the floor panel 4, and a battery tray 41 that protrudes below the opening 4A is fixed to the floor panel 4 so as to close the opening 4A.

The battery mounting space is located between the left and right side frames 13, 13 and between the front and

rear cross members

5, 6 in the width direction and the front-rear direction, and is located between the seat 2 and the battery tray 41 in the vertical direction. located between.
As mentioned above, since the widthwise middle part of the front cross member 5 is separated from the rear cross member 6, the distance between the two

cross members

5 and 6 is expanded, and the length is relatively long in the longitudinal direction of the vehicle. A certain number of batteries 3 can be accommodated. Furthermore, the height of the mounting space increases by the amount that the tray body 42 protrudes below the opening 4A. Therefore, a relatively tall battery 3 can be accommodated.

As described above, the battery mounting structure of this embodiment includes the floor panel 4, the two

cross members

5 and 6, the opening 4A, and the battery tray 41. A part of the battery case 30 that accommodates the battery pack 31 can be accommodated in the internal space located below the battery.

Here, details of the structure of the battery attachment part will be explained with reference to FIGS. 6 and 7. Note that FIGS. 6 and 7 show the part of the cross member 6 that is welded and fixed to the floor panel 4, and the explanation will focus on the rear cross member 6 here, but this also applies to the part that is welded and fixed to the front cross member 5. It is constructed in the same way with front and back symmetry.

As shown in FIGS. 4, 6, and 7, the battery tray 41 includes a bead-shaped curved portion 44 formed between the tray body 42 and the tray flange portion 43 over the entire circumference. The bead-shaped curved portion 44 is raised above the tray flange portion 43 when fixed to the floor panel 4, and has a convex cross-section. Further, in the battery tray 41 fixed to the floor panel 4, a sealing material 45 is attached over the entire circumference between the opening edge 4B of the floor panel 4 and the edge of the tray flange 43.

The tray flange portion 43 is welded and fixed to the lower surface 4c of the opening edge 4B of the floor panel 4. Further, the

flange portions

53 and 63 on one side (the side closer to the opening 4A) of each

cross member

5 and 6 are welded and fixed to the upper surface 4d of the opening edge 4B of the floor panel 4. Therefore, at the opening edge 4B of the floor panel 4 to which each

cross member

5, 6 is fixed, the flange portion 43, the opening edge 4B of the floor panel 4, and the

flange portion

53, 63 of each

cross member

5, 6. are stacked in this order from the bottom.

The top portion 44a (the uppermost portion) of the bead-shaped curved portion 44 is formed to protrude so as to be located above the

upper surfaces

53a, 63a of the

flange portions

53, 63 of each

cross member

5, 6. . Further, as shown in FIG. 7, the

edges

53b, 63b of the

flange portions

53, 63 of each

cross member

5, 6 located above the opening edge 4B (the edge facing the opening 4A, the edge 53b) (see FIG. 1), the opening edge 4e (the edge facing the opening 4A) of the opening edge 4B located on the tray flange portion 43, as shown by the dashed line and arrow in the figure. It is arranged to be shifted away from 4A. Hereinafter, the

edges

53b, 63b of the

flange portions

53, 63 will be referred to as "flange edges 53b, 63b."

Above the tray flange portion 43, there is a sealing material storage area surrounded by the bead-shaped curved portion 44 arranged in this manner, the edge 4e of the opening edge 4B of the floor panel 4, and the flange edges 53b, 63b. A space 46 (dot pattern in FIG. 7) is formed. By providing the bead-shaped curved portion 44, the liquid sealant 45 tends to accumulate in the sealant storage space 46, and the sealing performance (waterproofness) of the solidified sealant 45 is improved.

[2. action, effect]
(1) In the battery attachment structure described above, the bead-shaped curved portion 44 of the battery tray 41 becomes a reinforcing structure that compensates for the decrease in rigidity and strength around the opening 4A of the floor panel 4. That is, although the rigidity near the opening edge 4B may be reduced by forming the opening 4A in the floor panel 4, the tray flange 43 of the battery tray 41 is fixed to the opening edge 4B. A bead-shaped curved portion 44 that is raised upwards from the tray flange portion 43 is formed inside the tray flange portion 43 (on the tray main body 42 side). By forming the bead-shaped curved portion 44 as a reinforcing structure, the shape rigidity around the opening 4A can be increased.

Furthermore, since the liquid sealant 45 tends to accumulate due to the bead-shaped curved portion 44, the sealant 45 can be installed at an appropriate position. In addition, the bead-shaped curved portion 44 acts as a dam to prevent water from entering the tray body 42 even when water enters from the seal between the opening edge 4B of the floor panel 4 and the tray flange 43. It also functions as These improve the waterproofness within the battery tray 41. Therefore, the waterproofness of the battery 3 can be improved while increasing the shape rigidity.

(2) Furthermore, since the top portion 44a of the bead-shaped curved portion 44 is located above the

upper surfaces

53a, 63a of the

flange portions

53, 63 of the

cross members

5, 6, it functions as a dam for the bead-shaped curved portion 44. can be further increased. As a result, as shown by the thick arrow in FIG. 7, water that is about to enter (for example, condensed water dripping down the cross members 5 and 6) can be dammed up, thereby improving the waterproofness inside the battery tray 41. It can be further improved.

(3) Furthermore, the sealing material 45 is applied from above inside the vehicle compartment to the edge 4e of the opening edge 4B above the tray flange 43 and to the flange portions 53 of the

cross members

5 and 6 above the opening edge 4B. , 63 at the end edges 53b, 63b. At this time, for example, if the flange edges 53b, 63b are closer to the opening 4A side than the edge 4e of the opening edge 4B, the edge 4e of the opening edge 4B is closer to the

flange edge

53b, 63b. The sealing material 45 is also recessed inward, which may lead to improper installation of the sealing material 45.

In contrast, in the above structure, the flange edges 53b, 63b of the

cross members

5, 6 are spaced apart from the opening 4A with respect to the edge 4e of the opening edge 4B of the floor panel 4 on the tray flange portion 43. It is placed off to the side where it is placed. Therefore, workability when attaching the sealing material 45 to the flange edges 53b, 63b can be improved. Moreover, the above-mentioned installation failures can be avoided, and the installation properties of the sealing material 45 can also be improved. Therefore, it becomes easier to ensure waterproof sealing performance.

(4) Further, above the tray flange portion 43, there is a sealing material storage space surrounded by the bead-shaped curved portion 44, the edge 4e of the opening edge 4B, and the flange edges 53b, 63b of the

cross members

5, 6. 46 is formed. Therefore, when installing the sealing material 45, it is only necessary to install the sealing material 45 so as to fill the sealing material accommodation space 46, thereby making it possible to further improve the installation properties of the sealing material 45 and improving the waterproof sealing performance. It becomes easier to secure.

(5) Furthermore, the opening 32a of the undercase 32 of the battery case 30 is located above the upper surfaces 51a, 61a of the

top wall portions

51, 61 of each

cross member

5, 6. Such a positional relationship constitutes a water-stopping structure that closes the gap between the under case 32 and the upper case 33. Thereby, even if water enters onto the floor panel 4 and exceeds the bead-shaped curved portion 44, it is possible to prevent water from entering into the battery case 30.

[3. Modified example]
The configuration of the battery attachment structure described above is one example, and is not limited to the above-mentioned configuration.
For example, the vertical positional relationship between the top portion 44a of the bead-shaped curved portion 44 and the

upper surfaces

53a, 63a of the

flange portions

53, 63 is not limited to the above. By providing at least the bead-shaped curved portion 44, it is possible to compensate for the decrease in rigidity and strength around the opening 4A of the floor panel 4.

The positional relationship between the flange edges 53b, 63b of the

cross members

5, 6 and the edge 4e of the opening edge 4B is not limited to the above. For example, the flange edges 53b, 63b may be spaced apart from the opening 4A by the same extent as the edge 4e of the opening edge 4B, or the flange edges 53b, 63b may be farther away from the opening 4A than the edge 4e of the opening edge 4B. Even if the flange edges 53b, 63b are not too close to the opening 4A than the edge 4e of the opening edge 4B, the workability of installing the sealing material 45 may be reduced. , it is possible to attach the sealing material 45.

Furthermore, the vertical positional relationship between the opening 32a of the undercase 32 of the battery case 30 and the upper surfaces 51a, 61a of the

top walls

51, 61 of each

cross member

5, 6 is not limited to the above. By separately providing a water stop structure (seal structure) that closes the gap between the under case 32 and the upper case 33, the vertical positional relationship can be set as appropriate, and the configuration of the battery case 30 may also be changed as appropriate.
Note that the configuration of the vehicle floor panel 4 and the shapes of the

cross members

5 and 6 are also examples, and are not limited to those described above.

This case includes an opening formed between two cross members in a floor panel, and a battery tray fixed to the floor panel so as to close this opening from below. The present invention can be used in the vehicle manufacturing industry in which a part of a battery case that stores a battery pack can be accommodated in an internal space located in the interior space.

1

Vehicle interior

2, 2A, 2B Seat 3 Running battery (battery)
4 Floor panel 4A Opening 4B Opening edge 4c Lower surface of opening edge 4d Upper surface of opening edge 4e Edge of opening edge 5 Front cross member (cross member)
6 Rear cross member (cross member)
7 Bracket 30 Battery case 31 Battery pack (battery module)
32 Under case 32a Opening of under case 33 Upper case 41 Battery tray 42 Tray body 43 Tray flange portion 44 Bead-shaped curved portion 44a Top of bead-shaped curved portion 45 Seal material 46 Seal

material storage space

53, 63

Flange portion

53a, 63a Flange Upper surface of 53b, 63b Edge of flange, edge of flange

Claims

A floor panel of a vehicle, two cross members arranged spaced apart from each other in the front and rear on the floor panel, an opening formed between the two cross members in the floor panel, and the opening. a battery tray fixed to the floor panel so as to close the opening from below, and a part of the battery case for storing the battery pack is accommodated in an internal space located below the opening of the battery tray. A possible battery mounting part structure,
The battery tray includes a tray body that protrudes below the opening when fixed to the floor panel, and a tray body that is bent over the entire outer periphery of the upper edge of the tray body, and has a tray body that is bent around the entire outer periphery of the upper edge of the tray body, a tray flange portion welded and fixed to the opening edge of the tray, and a tray flange portion formed along the entire circumference between the tray body and the tray flange portion, and raised above the tray flange portion when fixed to the floor panel. a bead-shaped curved portion;
A battery attachment structure, characterized in that a sealing material is installed between the opening edge of the floor panel and the tray flange.
The tray flange portion is welded and fixed to the lower surface of the opening edge of the floor panel,
Each of the cross members has a hat-shaped cross section with a flange at the bottom, and the flange at a location corresponding to the opening edge of the floor panel is welded and fixed to the upper surface of the opening edge. ,
2. The battery attachment structure according to claim 1, wherein the top of the bead-shaped curved portion is located above the upper surface of the flange portion of the cross member.
An edge of the flange portion located above the opening edge is disposed to be shifted away from the opening with respect to an edge of the opening edge located above the tray flange. The battery attachment structure according to claim 2, characterized in that:
A sealing material storage space surrounded by the bead-shaped curved portion, the edge of the opening edge, and the edge of the flange is formed above the tray flange. The battery attachment structure according to claim 3.
The battery case includes an undercase having an opening at the top, and an upper case attached to the undercase so as to close the opening, and is fixed to each of the cross members via a bracket,
The battery attachment structure according to claim 1, wherein the opening of the undercase is located above each of the cross members.