Vehicle

Abstract

The invention provides a vehicle in which a seat is directly mounted on a battery cover, and the rigidity of the battery cover can be sufficiently ensured to bear a load from the seat. A vehicle (V) is provided with a vehicle body frame (1) and a battery pack (20) attached to the vehicle body frame (1). The vehicle body frame (1) has a pair of side frames (5) extending in the front-rear direction and disposed on both sides in the left-right direction. The battery pack (20) is fixed to the pair of side frames (5). A battery case (23) of a battery pack (20) is provided with: a case main body (30) in which a battery (21) is disposed; and a battery cover (40A), the upper surface of which constitutes the bottom panel of the vehicle (V). The battery cover (40A) is integrally provided with a cross beam part (42) extending in the left-right direction, and the upper part of the cross beam part is provided with seats (7L) and (7R) on which an occupant can sit.

Description

Technical Field

[0001] The present invention relates to a vehicle having a battery pack mounted on a vehicle body frame. Background Art

[0002] In recent years, in order to ensure that more people have access to affordable, reliable, sustainable and advanced energy, research and development related to secondary batteries that contribute to energy efficiency has been carried out.

[0003] For example, Patent Document 1 describes a vehicle equipped with a battery pack in which a plurality of battery modules are accommodated in a case. In Patent Document 1, the battery pack is fixed to the lower portion of a vehicle body frame, and the upper surface of the case constitutes a part of the floor of the vehicle.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: International Publication No. 2022 / 251284 Summary of the invention

[0007] Problems to be solved by the invention

[0008] Although Patent Document 1 describes a structure in which a seat mounting member is provided on the upper surface of a housing, there is still room for improvement in order to ensure sufficient rigidity of the housing to bear the load from the seat.

[0009] The present invention provides a vehicle in which a seat is directly mounted on a battery cover of a battery pack, and the rigidity of the battery cover is sufficiently ensured to bear the load from the seat, thereby contributing to energy efficiency.

[0010] Means for solving problems

[0011] The present invention is a vehicle comprising:

[0012] body frame; and

[0013] a battery pack having a battery and a battery case for accommodating the battery and mounted on the vehicle body frame,

[0014] in,

[0015] The vehicle body frame includes a pair of side frames extending in the front-rear direction and arranged on both sides in the left-right direction.

[0016] The battery pack is fixed to the pair of side frames,

[0017] The battery housing has:

[0018] a housing body for arranging the battery; and

[0019] a battery cover which covers the housing body from above and whose upper surface constitutes a floor panel of the vehicle,

[0020] The battery cover is integrally provided with a beam portion, the beam portion extending in the left-right direction, and a seat on which an occupant can sit is mounted on an upper portion.

[0021] Effects of the Invention

[0022] According to the present invention, the seat is directly mounted on the battery cover, and thus the rigidity of the battery cover can be ensured to be sufficient to bear the load from the seat. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is an exploded perspective view of a vehicle V according to one embodiment of the present invention.

[0024] Figure 2 It is an external perspective view of the battery pack 20 fixed to the pair of side frames 5 and the seats 7L and 7R attached to the battery cover 40A of the battery pack 20 .

[0025] Figure 3 It is an exploded perspective view of the battery case 23 .

[0026] Figure 4 It is a top view of the battery pack 20 .

[0027] Figure 5 It is a perspective view of the appearance of the battery pack 20 fixed to the side member 4 and the side frame 5 .

[0028] Figure 6 It is an enlarged perspective view of the expansion member 45 attached to the beam portion 42 .

[0029] Figure 7 is along Figure 5 A cross-sectional view taken along line VII-VII.

[0030] Description of Reference Numerals

[0031] 1 Body frame

[0032] 4 Side beam

[0033] 5 Side frame

[0034] 7L, 7R seats

[0035] 71 Seat bracket

[0036] 72 Seat Track

[0037] 20 Battery pack

[0038] 21. Battery

[0039] 23 Battery housing

[0040] 30 Shell body

[0041] 40A battery cover

[0042] 42 Beam

[0043] 42f Front cross member (first cross member)

[0044] 42c Central beam section (second beam section)

[0045] 43f Front side frame part (frame part)

[0046] 45 Extension parts

[0047] V Vehicle. DETAILED DESCRIPTION

[0048] Hereinafter, a vehicle according to an embodiment of the present invention will be described with reference to the accompanying drawings. In addition, the accompanying drawings are views viewed in the directions indicated by the accompanying drawings. In the following description, front and rear, left and right, and up and down are directions viewed from the perspective of the driver. In the accompanying drawings, the front of the vehicle is indicated as Fr, the rear is indicated as Rr, the left is indicated as L, the right is indicated as R, the top is indicated as U, and the bottom is indicated as D. In addition, the left and right directions are sometimes referred to as vehicle width directions.

[0049] like Figure 1 As shown, the vehicle V includes a body frame 1 constituting a skeleton of the vehicle V, a front suspension 11 disposed at the front of the vehicle V, left and right front wheels 12 supported by the front suspension 11, a rear suspension 13 disposed at the rear of the vehicle V, left and right rear wheels 14 supported by the rear suspension 13, a motor 15 disposed at the front of the vehicle V and serving as a power source of the vehicle V, and a battery pack 20 mounted on the body frame 1. The vehicle V is, for example, an electric vehicle that supplies the power stored in the battery pack 20 to the motor 15 and travels using the power of the motor 15. In addition, the vehicle V may also be a hybrid vehicle that further includes an engine and can travel using the power of the engine and / or the motor 15.

[0050] The vehicle body frame 1 includes a front frame 2 provided in front of a battery pack 20, a rear frame 3 provided in rear of the battery pack 20, and a side member 4 connected to the front frame 2 and the rear frame 3. The front frame 2 forms a power room for accommodating a power source such as a motor 15. The rear frame 3 is arranged outside in the left-right direction of a rear bottom panel 6 forming a floor portion of a luggage compartment, and extends in the front-rear direction.

[0051] The vehicle body frame 1 also includes a pair of side frames 5, which are fixed to the lower portion of the side beam 4 and are provided on both sides of the battery pack 20 in the left-right direction. The side frames 5 are fastened to the battery pack 20 by bolts or other fastening members B1 (see FIG. Figure 7 ) is fixed to the side beam 4.

[0052] Furthermore, an opening 1a is provided at the lower portion of the vehicle body frame 1. The opening 1a is provided in front of the rear floor panel 6 and inside the side members 4 and the side frames 5 in the vehicle width direction. The battery pack 20 is mounted in the opening 1a portion.

[0053] The front suspension 11 is provided in front of the battery pack 20 and is fixed to the vehicle body frame 1 . The front wheel 12 is supported by the vehicle body frame 1 via the front suspension 11 .

[0054] The rear suspension 13 is provided behind the battery pack 20 and is fixed to the vehicle body frame 1 . The rear wheel 14 is supported by the vehicle body frame 1 via the rear suspension 13 .

[0055] like Figures 2 to 4 As shown, the battery pack 20 includes a battery 21 (see Figure 7 ), an auxiliary machine 22 electrically connected to the battery 21, and a battery casing 23 for accommodating them.

[0056] The storage battery 21 is, for example, an all-solid-state battery. Although not shown in the figure, each cell of the storage battery 21 composed of an all-solid-state battery includes a positive electrode, a negative electrode, and a solid electrolyte disposed between the positive electrode and the negative electrode, which are sealed and packaged by an outer body such as a laminate film. The storage battery 21 is charged and discharged by the transfer of lithium ions between the positive electrode and the negative electrode via the solid electrolyte.

[0057] As a solid electrolyte, there is no particular limitation as long as it has lithium ion conductivity and insulation, and materials commonly used in all-solid-state lithium-ion batteries can be used. For example, sulfide solid electrolyte materials, oxide solid electrolyte materials, inorganic solid electrolytes such as lithium salts, and polymer solid electrolytes such as polyethylene oxide can be listed. There is no particular limitation on the form of the solid electrolyte material, and for example, particles can be listed.

[0058] The auxiliary device 22 includes, for example, a junction box to which wiring components are mounted, through which charging current and discharging current of the battery 21 flow. The auxiliary device 22 is electrically connected to the battery 21 via, for example, a bus bar (not shown).

[0059] The battery case 23 includes a case body 30 that is a bottomed container type, and a case cover 40 that covers the case body 30 from above.

[0060] like Figure 3As shown, the housing body 30 has a battery storage chamber 31 for arranging the battery 21, and an auxiliary machine storage chamber 32 for arranging the auxiliary machine 22. The battery storage chamber 31 is divided into two parts by a central wall portion 33 extending in the left-right direction, and the battery 21 is accommodated in each battery storage chamber 31. The auxiliary machine storage chamber 32 is provided at the front part of the housing body 30, and is provided in front of the battery storage chamber 31 via a partition wall portion 34.

[0061] The housing cover 40 includes a battery cover 40A that covers the battery storage chamber 31 from above, and an auxiliary machine cover 40B that covers the auxiliary machine storage chamber 32 from above. Figure 1 and Figure 2 As shown, the upper surface 41 of the housing cover 40 (i.e., the upper surface of the battery cover 40A and the upper surface of the auxiliary machine cover 40B) constitutes the bottom panel of the vehicle V. In other words, the bottom panel and the housing cover 40 are combined and constituted by a single component. As a result, it is not necessary to separately provide the bottom panel and the housing cover 40, so that the vehicle V can be made lighter.

[0062] Furthermore, since the auxiliary machine 22 is housed in the battery case 23 at a position forward of the battery 21, the case cover 40 can be flattened compared to a structure in which the auxiliary machine is arranged above the battery in the battery case. Therefore, the foot space in the vehicle cabin can be expanded.

[0063] Two seats 7L and 7R arranged in the left-right direction for seating passengers are mounted on the battery cover 40A. Each seat 7L and 7R is slidable in the front-rear direction and is attached to the battery cover 40A via a seat bracket 71 and a seat rail 72 described later.

[0064] A console box 8 is mounted above the auxiliary machinery cover 40B. The console box 8 is attached to a center portion in the left-right direction of the auxiliary machinery cover 40B at a position in front of the seats 7L, 7R.

[0065] Next, the details of the battery cover 40A will be described in detail.

[0066] like Figure 3 and Figure 4 As shown, the battery cover 40A includes a plurality of beam portions 42 extending in the left-right direction, and a plurality of frame portions 43 extending in the front-rear direction and intersecting the beam portions 42 .

[0067] The plurality of beam portions 42 are integrally provided on the upper surface 41 of the battery cover 40A, and function as reinforcement portions that increase the rigidity of the battery cover 40A.

[0068] In the present embodiment, three cross beams 42 are provided, including a front cross beam 42f provided at the front of the battery cover 40A, a central cross beam 42c provided at the center of the battery cover 40A, and a rear cross beam 42r provided at the rear of the battery cover 40A. Each cross beam 42 is provided to protrude upward from the upper surface 41 of the battery cover 40A, and has a hat shape along the cross section of the plane perpendicular to the left and right direction. In addition, the number of cross beams 42 is not limited to three, and at least one cross beam 42 is sufficient.

[0069] Each cross beam 42 is configured such that both side portions in the left-right direction protrude outward in the left-right direction from the upper surface 41 of the battery cover 40A. Such a portion protruding outward in the left-right direction (also referred to as a protruding portion) is extended in the left-right direction above the side frame 5 in a state where the battery pack 20 is mounted on the vehicle body frame 1. In addition, the protruding portion of each cross beam 42 may be provided by a member different from the left-right inner portion of the cross beam 42 and joined by welding or the like, or may be provided integrally with the left-right inner portion of the cross beam 42.

[0070] The plurality of frame portions 43 are integrally provided on the upper surface 41 of the battery cover 40A. Similar to the beam portion 42, the frame portion 43 functions as a reinforcement portion that increases the rigidity of the battery cover 40A.

[0071] In this embodiment, five frame portions 43 are provided, including two front frame portions 43f provided between the front cross beam portion 42f and the central cross beam portion 42c, and three rear frame portions 43r provided between the central cross beam portion 42c and the rear cross beam portion 42r. Each frame portion 43 is also provided to protrude upward from the upper surface 41 of the battery cover 40A.

[0072] The two front frame parts 43f are arranged approximately in the center in the left-right direction, connected to the front cross beam part 42f and the central cross beam part 42c and extended. The front cross beam part 42f, the central cross beam part 42c and the front frame part 43f constitute a reinforcement part that is approximately H-shaped in a plan view, further improving the rigidity of the battery cover 40A.

[0073] The three rear frame portions 43r are respectively provided at the right side, the center, and the left side in the left-right direction, and the right and left rear frame portions 43r are connected to the center cross beam portion 42c and the rear cross beam portion 42r and extended.

[0074] Next, refer to Figures 4 to 7 The fixation of the battery pack 20 and the vehicle body frame 1 will be described.

[0075] like Figure 4As shown, the case body 30 has a plurality of vehicle body fixing portions 35 at the front edge and the rear edge. By fastening these vehicle body fixing portions 35 to the vehicle body frame 1 , the battery pack 20 is fixed to the vehicle body frame 1 at the front edge and the rear edge.

[0076] In addition, if Figure 7 As shown, a battery fixing bracket 36 is provided at the left edge of the housing body 30, and the housing body 30 is fixed to the left side frame 5 via the battery fixing bracket 36. In addition, the upper surface of the side frame 5 extends toward the battery pack 20, and a side frame fixing portion 37 directly fixed to the pair of side frames 5 is provided on the side wall portion of the housing body 30. In addition, the right edge of the housing body 30 and the right side frame 5 are fixed in the same manner.

[0077] In addition, if Figures 5 to 7 As shown in FIG. 1 , an expansion member 45 is provided at both ends (i.e., the extended portion) in the left-right direction of each cross beam portion 42. The expansion member 45 is provided to extend in the left-right direction above the side frame 5. The cross section of the expansion member 45 also has a hat shape, similar to each cross beam portion 42. The expansion member 45 is provided to cover both ends of each cross beam portion 42 from above, and is attached to each cross beam portion 42 via a fastening member B2 such as a bolt.

[0078] The expansion member 45 and the side frame 5 are fixed by a fastening member B3 such as a bolt. In more detail, the expansion member 45 is provided separately from the side frame 5 in the up-down direction, but the fastening member B3 is inserted through the expansion member 45, the cross beam 42 and the side frame 5 to fix them. In this way, both ends of each cross beam 42 are fixed to the side frame 5 by the expansion member 45. Each cross beam 42 is fixed to the side frame 5 by the expansion member 45, so that the rigidity of the battery cover 40A can be ensured.

[0079] The expansion member 45 and the side member 4 are fixed, for example, by spot welding or the like. Specifically, the expansion member 45 is fixed to the side member 4 at the end 45a in the left-right direction. In this way, each cross member 42 is also fixed to the side member 4 via the expansion member 45. Each cross member 42 is extended in the left-right direction to such an extent that it does not interfere with the side member 4 when the battery pack 20 is mounted in the opening 1a portion of the vehicle body frame 1 from below, and is fixed to the side member 4 by the expansion member 45, so that the rigidity of the battery cover 40A can be ensured.

[0080] In this way, the battery pack 20 is fixed to the vehicle body frame 1 by the vehicle body fixing portion 35 , the battery fixing bracket 36 and the side frame fixing portion 37 provided on the case body 30 , and the expansion member 45 provided on each cross member 42 .

[0081] Each cross beam 42 is fixed to the side beam 4 and the side frame 5 via the expansion member 45 , so that when the vehicle V collides sideways, the load input from the side beam 4 and the side frame 5 to the inner side in the vehicle width direction can be transferred to the cross beam 42 , thereby protecting the battery 21 housed in the battery case 23 .

[0082] In addition, if Figure 7 As shown, each cross member 42 is disposed opposite to the side members 4 in the left-right direction. Thus, load input from the side members 4 to the inner side in the vehicle width direction during a side collision of the vehicle V can be well transmitted to the cross member 42 without deviation.

[0083] Next, the attachment of the seats 7L, 7R to the housing cover 40 will be described.

[0084] like Figure 2 As shown, the seats 7L and 7R are mounted on the cross beam portion 42 of the battery cover 40A. As described above, the cross beam portion 42 is a high-rigidity portion that functions as a reinforcement portion, so even in a structure in which the seats 7L and 7R are directly mounted on the battery cover 40A, the rigidity of the battery cover 40A can be sufficiently ensured to withstand the load caused by the weight of the seats 7L and 7R and the weight of the occupants sitting on the seats 7L and 7R.

[0085] In addition, the seats 7L and 7R are mounted across the front cross beam 42f and the center cross beam 42c of the battery cover 40A. In this way, a plurality of cross beams 42 for mounting the seats 7L and 7R are provided, so that the rigidity of the battery cover 40A can be further increased to withstand the load from the seats, and the battery cover 40A can stably support the seats 7L and 7R.

[0086] Furthermore, seat rails 72 are provided at the right and left ends of the seats 7L and 7R, and are laid over the front cross beam 42f and the center cross beam 42c. With such a structure, the seat rails 72 themselves can also contribute to improving the rigidity of the battery cover 40A.

[0087] Seat brackets 71 to which the seats 7L and 7R are mounted are provided at both ends of the front cross beam 42f in the left-right direction. The right front end of the right seat 7R and the left front end of the left seat 7L are fixed to the seat brackets 71 via seat rails 72. In addition, the right rear end of the right seat 7R and the left rear end of the left seat 7L are fixed to both ends of the central cross beam 42c in the left-right direction.

[0088] Furthermore, a seat bracket 71 is also provided at the center portion in the left-right direction of the front cross beam portion 42f. The right front end portion of the left seat 7L and the left front end portion of the right seat 7R are fixed to the seat bracket 71 via a seat rail 72. Furthermore, the right rear end portion of the left seat 7L and the left rear end portion of the right seat 7R are fixed to the center portion of the center cross beam portion 42c via a seat rail 72.

[0089] The expansion member 45 fixed to the side frame 5 is a high-rigidity portion, and a portion of the seat 7L, 7R is fixed near such a high-rigidity portion. Therefore, the battery pack 20 can support the seat 7L, 7R at the high-rigidity portion.

[0090] Furthermore, since the seat bracket 71 is disposed above the side frame 5 , the seats 7L and 7R are indirectly supported by the side frame 5 , and the seats 7L and 7R can be supported by the battery cover 40A and the side frame 5 .

[0091] Furthermore, since the seat bracket 71 provided at the center portion of the front cross member 42f in the left-right direction is connected to the front frame portion 43f, the seats 7L, 7R can be supported at a high rigidity portion also at the center portion in the vehicle width direction.

[0092] Above, one embodiment of the present invention has been described with reference to the accompanying drawings, but the present invention is certainly not limited to this embodiment. Obviously, those skilled in the art can think of various variations or modifications within the scope of the scope of the claims, and it should be understood that these variations and modifications also belong to the technical scope of the present invention. In addition, the various constituent elements in the above-mentioned embodiments may also be arbitrarily combined within the scope of the gist of the invention.

[0093] For example, in the above-described embodiment, the two seats 7L and 7R are mounted on the battery cover 40A, but the number of seats is not limited to two, and may be one or three or more.

[0094] At least the following matters are described in this specification: In parentheses, corresponding components in the above-mentioned embodiment are shown as an example, but the present invention is not limited to this.

[0095] (1) A vehicle (vehicle V) comprising:

[0096] a body frame (body frame 1); and

[0097] A battery pack (battery pack 20) ​​includes a battery (battery 21) and a battery case (battery case 23) for accommodating the battery, and is mounted on the vehicle body frame.

[0098] in,

[0099] The vehicle body frame includes a pair of side frames (side frames 5) extending in the front-rear direction and arranged on both sides in the left-right direction.

[0100] The battery pack is fixed to the pair of side frames,

[0101] The battery housing has:

[0102] A housing body (housing body 30 ) for arranging the battery; and

[0103] a battery cover (battery cover 40A) which covers the housing body from above and whose upper surface constitutes a floor panel of the vehicle,

[0104] The battery cover is integrally provided with a beam portion (beam portion 42 ) that extends in the left-right direction and has seats (seats 7L, 7R) on which passengers can sit mounted.

[0105] According to (1), the upper surface of the battery cover constitutes the bottom panel, so there is no need to provide a separate bottom panel, which can achieve a lightweight vehicle. In addition, in a structure in which the seat is directly mounted on the battery cover constituting the bottom panel, a cross beam portion is integrally provided on the battery cover, and the seat is mounted on the cross beam portion, so that the rigidity of the battery cover can be sufficiently ensured to withstand the load from the seat.

[0106] (2) The vehicle according to (1), wherein:

[0107] The cross beam portion includes a first cross beam portion (front cross beam portion 42f) and a second cross beam portion (center cross beam portion 42c) arranged in parallel along the front-rear direction.

[0108] The seat is mounted across the first cross beam portion and the second cross beam portion.

[0109] According to (2), the battery cover is provided with a plurality of beam portions on which the seat is mounted, so that the rigidity of the battery cover can be further increased to bear the load from the seat.

[0110] (3) The vehicle according to (2), wherein:

[0111] A seat rail (seat rail 72 ) that enables the seat to slide is provided between the first cross beam portion and the second cross beam portion.

[0112] According to (3), the seat rails spanning the first cross beam portion and the second cross beam portion contribute to improving the rigidity of the battery cover.

[0113] (4) The vehicle according to (2) or (3), wherein:

[0114] The battery cover is provided with a frame portion (front frame portion 43 f ) that is connected to the first cross beam portion and the second cross beam portion at a substantially central portion in the left-right direction and extends in the front-rear direction.

[0115] According to (4), the first beam portion, the second beam portion, and the frame portion constitute the reinforcing portion having an H shape in a plan view, and thus the rigidity of the battery cover can be further increased.

[0116] (5) The vehicle according to any one of (1) to (4), wherein:

[0117] The vehicle further includes an expansion member (expansion member 45) fixed to the pair of side frames.

[0118] Both ends of the beam portion in the left-right direction are fixed to the pair of side frames via the expansion member.

[0119] According to (5), the rigidity of the battery cover can be ensured by fixing the cross member to the side frame by the expansion member.

[0120] (6) The vehicle according to (5), wherein:

[0121] Seat brackets (seat brackets 71 ) to which the seat is mounted are provided at the both end portions of the cross beam portion in the left-right direction.

[0122] According to (6), the extension member fixed to the side frame is a high-rigidity portion of the battery cover, and the seat bracket is provided near the high-rigidity portion. Therefore, the battery pack can support the seat at the high-rigidity portion.

[0123] (7) The vehicle according to (6), wherein:

[0124] The two ends of the cross beam are extended to above the pair of side frames.

[0125] The seat bracket is arranged above the pair of side frames.

[0126] According to (7), the side frame can also support the load from the seat.

[0127] (8) The vehicle according to any one of (1) to (7), wherein:

[0128] A seat bracket (seat bracket 71) is provided on the cross beam portion. The seat bracket is provided at the center portion in the left-right direction and is provided for mounting the seat.

[0129] The battery cover is provided with a frame portion (front frame portion 43 f ) that extends in the front-rear direction and is connected to the seat bracket.

[0130] According to (8), the seat bracket is provided at the high-rigidity portion of the frame portion, so the battery pack can support the seat at the high-rigidity portion.

[0131] (9) The vehicle according to any one of (1) to (8), wherein:

[0132] The vehicle body frame further includes a side beam (side beam 4) fixed to the pair of side frames.

[0133] The cross beam portion is fixed to the pair of side frames and the side beams via extension members (extension members 45 ) extending from both end portions in the left-right direction.

[0134] According to (9), the cross beam is fixed to the side frame and the side beam via the expansion member, so that the rigidity of the battery cover can be ensured. Therefore, when the vehicle collides, the load input from the side frame and the side beam can be transmitted to the cross beam, and the battery housed in the battery case can be protected.

[0135] (10) The vehicle according to any one of (1) to (9), wherein:

[0136] The vehicle body frame further includes a side beam (side beam 4) fixed to the pair of side frames.

[0137] The cross beam portion is arranged to face the side beam in the left-right direction.

[0138] According to (10), the load input from the side members during a vehicle collision can be well transmitted to the cross member portion of the battery cover without deviation.

Claims

1. A vehicle comprising: body frame; and a battery pack having a battery and a battery case for accommodating the battery and mounted on the vehicle body frame, in, The vehicle body frame includes a pair of side frames extending in the front-rear direction and arranged on both sides in the left-right direction. The battery pack is fixed to the pair of side frames. The battery housing has: a housing body for arranging the battery; and a battery cover which covers the housing body from above and whose upper surface constitutes a floor panel of the vehicle, The battery cover is integrally provided with a beam portion, the beam portion extending in the left-right direction, and a seat on which an occupant can sit is mounted on an upper portion.

2. The vehicle according to claim 1, wherein: The cross beam portion includes a first cross beam portion and a second cross beam portion arranged in parallel along the front-rear direction. The seat is mounted across the first cross beam portion and the second cross beam portion.

3. The vehicle according to claim 2, wherein: A seat rail that enables the seat to slide is mounted on the first beam portion and the second beam portion.

4. The vehicle according to claim 2, wherein: The battery cover is provided with a frame portion that is connected to the first beam portion and the second beam portion at a substantially central portion in the left-right direction and extends in the front-rear direction.

5. The vehicle according to any one of claims 1 to 4, wherein: The vehicle further includes an expansion member fixed to the pair of side frames. Both ends of the beam portion in the left-right direction are fixed to the pair of side frames via the expansion member.

6. The vehicle according to claim 5, wherein: Seat brackets to which the seat is mounted are provided at both end portions of the cross beam portion in the left-right direction.

7. The vehicle according to claim 6, wherein: The two ends of the cross beam are extended to above the pair of side frames. The seat bracket is arranged above the pair of side frames.

8. The vehicle according to any one of claims 1 to 4, wherein: A seat bracket is provided on the cross beam portion, the seat bracket is provided at the center portion in the left-right direction and is provided for the seat to be installed. The battery cover is provided with a frame portion, the frame portion extending in the front-rear direction and connected to the seat bracket.

9. The vehicle according to any one of claims 1 to 4, wherein: The vehicle body frame further includes a side beam fixed to the pair of side frames. The cross beam portion is fixed to the pair of side frames and the side beams via extension members extending from both end portions in the left-right direction.

10. The vehicle according to any one of claims 1 to 4, wherein: The vehicle body frame further includes a side beam fixed to the pair of side frames. The cross beam portion is arranged to face the side beam in the left-right direction.

Images