Electric vehicle

Abstract

To optimize a front-rear weight distribution of an electric vehicle and reduce yaw inertia moment to improve steering stability and motion performance.SOLUTION: An electric vehicle is provided with a battery unit BY1 stored in a tunnel part 11 of a floor panel 10, and a motor M, provided at the vehicle front side or rear side of the battery unit BY1, which drives driving wheels. The battery unit BY1 is configured to become heavier as separating from the motor M.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present disclosure relates to an electric vehicle that includes a motor that drives drive wheels and a battery that supplies power to the motor. [Background technology]

[0002] In an electric vehicle equipped with a motor that drives the drive wheels, the cruising range is largely determined by the size of the battery that supplies power to the motor. For example, in the case of the electric vehicle disclosed in Patent Document 1, batteries are installed in a tunnel portion formed in the floor panel, and also installed below the rear seat, thereby increasing the amount of battery capacity. The battery installed in the tunnel portion of the floor panel has an elongated shape in the front-to-rear direction because the tunnel portion is long in the front-to-rear direction, and the vertical dimension of the front end of the battery is longer than the vertical dimension of the middle portion of the battery (the middle portion in the front-to-rear direction). On the other hand, the battery installed below the rear seat has an elongated shape in the left-to-right direction because the rear seat is long in the left-to-right direction, thereby increasing the capacity.

[0003] Furthermore, Patent Document 2 discloses that a raised portion is formed on the passenger seat side of the floor panel, and a battery is disposed within the raised portion. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2011-1950566 [Patent Document 2] Japanese Patent Application Laid-Open No. 2008-155828 Summary of the Invention [Problem to be solved by the invention]

[0005] It is generally known that in order to improve the handling stability and maneuverability of an automobile, it is preferable to distribute the weight of the vehicle evenly between the front and rear and to place heavy objects as close as possible to the center of the vehicle in the longitudinal direction, and in fact, doing so improves the handling stability and maneuverability. Therefore, when designing an automobile, emphasis tends to be placed on distributing the weight of the vehicle evenly between the front and rear and placing heavy objects as close as possible to the center of the vehicle in the longitudinal direction.

[0006] In the case of electric vehicles, the motor is a heavy object that significantly affects the front-to-rear weight distribution of the vehicle. Similarly, the battery is also a heavy object that, like the motor, significantly affects the front-to-rear weight distribution of the vehicle, so careful consideration is required regarding its installation position.

[0007] However, in Patent Document 1, the motor that drives the drive wheels is mounted at the front of the vehicle body, and the battery mounted in the tunnel section of the floor panel has a long vertical dimension at the front end of the battery, making the front end of the battery relatively heavy. These two factors could cause the front-to-rear weight distribution of the vehicle to shift forward.

[0008] In addition, in Patent Document 1, a large-capacity battery that is long in the left-right direction is mounted below the rear seat, but this battery below the rear seat is located farther back from the center of the vehicle in the front-to-rear direction, making it difficult to move heavy objects closer to the center of the vehicle in the front-to-rear direction. Therefore, the electric vehicle in Patent Document 1 has room for improvement in handling stability and driving performance.

[0009] Furthermore, in Patent Document 2, the battery is mounted in a raised area located on the passenger side, but the front-to-rear weight distribution of the vehicle is not taken into consideration, so even the automobile in Patent Document 2 has room for improvement in terms of handling stability and driving performance.

[0010] The present disclosure has been made in consideration of the above points, and has as its object to optimize the front-rear weight distribution of an electric vehicle, reduce the yaw moment of inertia, and improve the handling stability and driving performance. [Means for solving the problem]

[0011] To achieve the above object, a first aspect of the present disclosure can be based on an electric vehicle. The electric vehicle includes a tunnel section provided in the center of the floor panel in the vehicle width direction, bulging upward and extending in the vehicle longitudinal direction, a battery unit housed in the tunnel section and including a plurality of batteries arranged in the vehicle longitudinal direction, and a motor provided in front or behind the battery unit and receiving power from the batteries to drive drive wheels. The battery unit is configured to become heavier with increasing distance from the motor.

[0012] That is, the floor panel is located between the front and rear wheels, i.e., in the longitudinal center of the vehicle, and the tunnel portion of this floor panel is located in the transverse center of the vehicle. Therefore, by accommodating the battery unit within the tunnel portion, it is possible to position the heavy object closer to the center of the vehicle. This reduces the yaw moment of inertia. Furthermore, if a motor, which is another heavy object, is located in front of or behind the battery unit, the battery unit is configured to become heavier with increasing distance from the motor, making it less likely that the front-to-rear weight distribution of the vehicle will be biased toward one side.

[0013] The battery unit according to the second aspect of the present disclosure may be configured such that the width of the battery unit increases with increasing distance from the motor when viewed from above the vehicle.

[0014] This configuration makes it possible to obtain a battery unit with a simple structure that becomes heavier with increasing distance from the motor.

[0015] The motor according to the third aspect of the present disclosure may be arranged so as to overlap at least a portion of the back of the seat in a side view of the vehicle.

[0016] According to this configuration, the motor and the back of the seat are laid out close to each other, which further reduces the yaw moment of inertia.

[0017] According to a fourth aspect of the present disclosure, the vehicle may further include a drive shaft that transmits rotational force of the motor to the drive wheels. In this case, the motor may be disposed closer to the center of the vehicle in the longitudinal direction than the drive shaft.

[0018] According to this configuration, the motor can be disposed between the front and rear wheels, resulting in a layout that is advantageous for front-to-rear weight distribution.

[0019] In a fifth aspect of the present disclosure, a left seat and a right seat may be provided on the left and right sides of the tunnel portion of the floor panel, respectively. In this case, a width of a portion of the battery unit between the left seat and the right seat is set narrower than a width of a portion of the battery unit forward of the left seat and the right seat.

[0020] According to this configuration, by relatively narrowing the width of the portion of the battery unit between the left and right seats, it is possible to ensure sufficient width for the left and right seats without increasing the width of the vehicle, thereby improving the livability of occupants seated in the left and right seats.

[0021] According to a sixth aspect of the present disclosure, the vehicle may further include a dash panel extending upward and in a vehicle width direction from a front end of the floor panel. In this case, the front end of the battery unit may be positioned rearward of the dash panel.

[0022] With this configuration, the front end of the battery unit is located inside the tunnel portion, thereby further reducing the yaw moment of inertia.

[0023] The motor according to a seventh aspect of the present disclosure may be provided behind the battery unit in the vehicle. Also, the height of the tunnel portion protruding from the floor panel may increase toward the front of the vehicle, and in this case, the height of the battery unit may increase toward the front of the vehicle so as to correspond to the height of the tunnel portion protruding from the floor panel.

[0024] With this configuration, since the motor is laid out at the rear of the vehicle, the battery unit is configured to become heavier toward the front of the vehicle. In this case, by increasing the bulge height of the tunnel section toward the front of the vehicle and by making the height of the battery unit correspond to the bulge height of the tunnel section, it is possible to simplify the layout of the battery unit, which becomes heavier with increasing distance from the motor.

[0025] In an eighth aspect of the present disclosure, a seat may be provided on the side of the tunnel portion of the floor panel, in which case an upper end of the tunnel portion may be positioned higher than an upper surface of a cushion portion of the seat.

[0026] According to this configuration, the height of the tunnel portion is sufficiently ensured, so that the amount of battery that can be accommodated in the tunnel portion can be increased. [Effects of the Invention]

[0027] As described above, the battery is housed in a tunnel section provided in the floor panel and is positioned so that it becomes heavier the further it is from the motor. This makes it possible to optimize the front-to-rear weight distribution of the electric vehicle and reduce the yaw moment of inertia, thereby improving handling stability and driving performance. [Brief explanation of the drawings]

[0028] [Figure 1]FIG. 1 is a left side view of an electric vehicle according to an embodiment of the present invention. [Figure 2] FIG. 2 is a plan view of the electric vehicle according to the embodiment of the present invention. [Figure 3] FIG. 3 is a plan view showing the interior of the electric vehicle with the roof, doors, interior materials, etc. omitted. [Figure 4] FIG. 4 is a cross-sectional view taken along line IV-IV in FIG. [Figure 5] FIG. 5 is a cross-sectional view taken along line VV in FIG. [Figure 6] FIG. 6 is a perspective view showing only the battery unit mounted on the vehicle body. DETAILED DESCRIPTION OF THE INVENTION

[0029] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Note that the following description of the preferred embodiments is merely exemplary in nature and is not intended to limit the present invention, its applications, or its uses.

[0030] 1 and 2 show the exterior of an electric vehicle 1 equipped with a vehicle body structure A according to an embodiment of the present invention. In the description of this embodiment, the front side of the vehicle will be simply referred to as the "front", the rear side of the vehicle will be simply referred to as the "rear", the right side of the vehicle will be simply referred to as the "right", and the left side of the vehicle will be simply referred to as the "left". The left-right direction of the vehicle is the vehicle width direction. When the electric vehicle 1 is viewed from the left or right side, it is referred to as a side view. When the electric vehicle 1 is viewed from above, it is referred to as a top view or a plan view.

[0031] The electric vehicle 1 is a passenger vehicle and may be, for example, a coupe, hatchback, or sedan. A bonnet hood 2 is provided at the front of the electric vehicle 1. A front luggage storage space R1 (shown only in FIG. 1 by a dashed line) capable of storing luggage is provided below the bonnet hood 2. Opening the bonnet hood 2 opens the front luggage storage space R1, allowing luggage to be loaded and unloaded.

[0032] A rear hood 3 is provided at the rear of the electric vehicle 1. A rear luggage storage space R2 (shown only in broken lines in FIG. 1) capable of storing luggage is provided below the rear hood 3. By opening the rear hood 3, the rear luggage storage space R2 is opened, allowing luggage to be loaded and unloaded. Note that one or both of the front luggage storage space R1 and the rear luggage storage space R2 may be used as spaces in which auxiliary machinery is disposed.

[0033] A left door 4 and a right door 5 are provided on the left and right sides of the electric vehicle 1, respectively, so that they can be opened and closed. The roof 6 may be a fixed roof, a removable roof, or a folding roof. In the case of a removable roof or a folding roof, the electric vehicle becomes an open-top car with no roof above the occupants.

[0034] The body structure A of the electric vehicle 1 has front wheels 7 and rear wheels 8 on the left and right, respectively, as well as a drive motor M (shown in FIGS. 4 and 5, hereinafter simply referred to as motor M) for driving the rear wheels 8. Conventionally known inverter circuits, sensors, driving operation equipment, etc., required for controlling the motor M can be used.

[0035] In this embodiment, the rear wheels 8 are the drive wheels, but the front wheels 7 may also be drive wheels, or both the front wheels 7 and the rear wheels 8 may be drive wheels. Which wheels are to be drive wheels can be selected by the arrangement of the motor M; if the motor M is mounted only on the rear side, only the rear wheels 8 are drive wheels; if the motor M is mounted only on the front side, only the front wheels 7 are drive wheels; and if the motor M is mounted both on the front and rear sides, only the front wheels 7 and the rear wheels 8 are drive wheels. The following explanation will be given for the case where the motor M is mounted only on the rear side.

[0036] As shown in Fig. 1, a passenger compartment R3 serving as a space for passengers is provided between the front wheels 7 and the rear wheels 8. As shown in Fig. 4, a vehicle body structure A of an electric vehicle 1 includes a floor panel 10 that forms the floor surface of the passenger compartment R3, and a dash panel 20 that forms the front wall of the passenger compartment R3. The vehicle body structure A also includes an inclined panel 16 that extends upward from the rear end of the floor panel 10 and is inclined so that it is positioned further rearward as it goes upward, and a rear panel 17 that extends rearward from the upper end of the inclined panel 16.

[0037] A tunnel section 11 that bulges upward and extends in the front-to-rear direction is formed in the center of the floor panel 10 in the vehicle width direction. The interior surfaces of the tunnel section 11, floor panel 10, and dash panel 20 are covered with interior materials (not shown). As shown in FIG. 3 , the vehicle body structure A also includes a right side sill 12 that extends in the front-to-rear direction along the right edge of the floor panel 10, and a left side sill 13 that extends in the front-to-rear direction along the left edge of the floor panel 10.

[0038] The front end of the tunnel portion 11 is located at the front end of the floor panel 10, and the rear end of the tunnel portion 11 is located at the rear end of the floor panel 10. Therefore, the tunnel portion 11 has a shape that extends continuously from the front end to the rear end of the floor panel 10.

[0039] The electric vehicle 1 is a right-hand drive vehicle. Therefore, the vehicle body structure A is provided with a passenger seat 30 as a left seat (seat) and a driver's seat 40 as a right seat (seat) on the left and right sides of the tunnel section 11 in the floor panel 10, respectively. Specifically, the passenger seat 30 is provided on the left side of the tunnel section 11 in the floor panel 10, and the passenger seat 30 is disposed between the tunnel section 11 and the left side side sill 13. The driver's seat 40 is provided on the right side of the tunnel section 11 in the floor panel 10, and the driver's seat 40 is disposed between the tunnel section 11 and the right side side sill 12. Therefore, the passenger seat 30 and the driver's seat 40 are disposed side by side in the vehicle width direction, with the tunnel section 11 sandwiched between them. Note that the electric vehicle 1 may be a left-hand drive vehicle, in which case the driver's seat 40 may be disposed on the left side and the passenger seat 30 on the right side. A rear seat may also be provided.

[0040] The driver's seat 40 includes a cushion 41 that primarily supports the occupant's buttocks and thighs, and a back 42 that extends upward from the rear end of the cushion 41 and primarily supports the occupant's waist, back, and shoulders. The cushion 41 forms a seating surface. The passenger seat 30 similarly includes a cushion 31 and a back 32. In FIG. 3, the hip point of the occupant seated in the driver's seat 40 is indicated by the symbol HP1, and the hip point of the occupant seated in the passenger seat 30 is indicated by the symbol HP2. Here, it is assumed that the seated occupant is of standard build and weight, but even if the occupant's build and weight change slightly, the positions of the hip points HP1 and HP2 do not change significantly. In FIG. 4, the hip point of the occupant seated in the passenger seat 30 is indicated by the symbol HP2.

[0041] If the driver's seat 40 is attached to the floor panel 10 so that it can slide in the fore-and-aft direction, the hip point HP1 will move in the fore-and-aft direction depending on the sliding position, but the hip point HP1 when the driver's seat 40 is located in a position that allows a passenger with a standard build to adopt a standard driving posture can be used as the reference. The same applies to the hip point HP2 on the passenger seat 30 side. The passenger seat 30 may also be attached to the floor panel 10 so that it cannot slide in the fore-and-aft direction.

[0042] The upper end of the tunnel section 11 is positioned higher than the upper surfaces of the cushion sections 31 and 41. By making the tunnel section 11 at this height, when the center battery unit BY1 (described later) is accommodated in the tunnel section 11, a wide accommodation space can be secured in the vertical direction.

[0043] As shown in Figures 4 and 5, the protruding height of the tunnel section 11 from the floor panel 10 (the protruding height from the portion where the passenger seat 30 and the driver's seat 40 are attached) increases toward the front. Therefore, the upper end of the tunnel section 11 gently slopes downward toward the rear. The passenger seat 30 and the driver's seat 40 are located on either side of the rear portion of the tunnel section 11, and in a side view, the rear portion of the tunnel section 11 overlaps with the passenger seat 30 and the driver's seat 40. Because the height of the portion of the tunnel section 11 that overlaps with the passenger seat 30 and the driver's seat 40 in a side view is low, for example, a passenger (driver) seated in the driver's seat 40 can cross the tunnel section 11 to get onto the passenger seat 30, and a passenger seated in the passenger seat 30 can cross the tunnel section 11 to get onto the driver's seat 40.

[0044] 3, the width of the tunnel section 11 (the dimension in the vehicle width direction) becomes wider toward the front. Specifically, the distance between the left and right walls of the tunnel section 11 becomes narrower toward the rear, and the width of the rear portion of the tunnel section 11 is narrower than the width of the front portion. Because the width of the portions of the tunnel section 11 that overlap with the passenger seat 30 and the driver's seat 40 in a side view is narrow, it is possible to ensure wide widths for the passenger seat 30 and the driver's seat 40 while suppressing an increase in the vehicle width.

[0045] Furthermore, since the front portion of the tunnel section 11 does not overlap with the passenger seat 30 and the driver's seat 40 in a side view, even if the width of this front portion is wide, it does not cause a problem in terms of ensuring the width of the passenger seat 30 and the driver's seat 40. Moreover, since only the feet of the driver and passenger in the passenger seat 30 are positioned to the sides of the front portion of the tunnel section 11, even if the width of the front portion of the tunnel section 11 is wide, it has almost no effect on the livability of the passenger seat 30 and the driver's seat 40.

[0046] The dash panel 20 extends upward and in the vehicle width direction from the front end of the floor panel 10 and is a member that separates the vehicle interior R3 from the space in front of the vehicle interior R3. A bulging portion 20a that bulges toward the vehicle interior R3 is provided in the center of the dash panel 20 in the vehicle width direction. As shown in FIG. 5, the lower end of the bulging portion 20a is connected to the front end of the tunnel portion 11.

[0047] 3 to 6, the vehicle body structure A includes a center battery unit BY1, a passenger-side battery unit BY2, a rear right battery unit BY3, and a rear left battery unit BY4. In this embodiment, the battery units BY1 to BY4 are arranged in various parts of the vehicle body, thereby making it possible to effectively utilize the multiple spaces formed in various parts of the vehicle body and increase the number of batteries that can be installed.

[0048] The center battery unit BY1 is housed within a tunnel section 11. A center battery mounting section (first battery mounting section) 11A in which the center battery unit BY1 can be mounted is provided in the tunnel section 11 and extends longitudinally, and the center battery unit BY1 mounted in the center battery mounting section 11A is fixed to a floor panel 10 or the like so as to be detachable (replaceable). When fixed to the floor panel 10 or the like, the front end of the center battery unit BY1 is positioned rearward of the dash panel 20. This eliminates the presence of a battery, which is a heavy object, in the front portion of the vehicle.

[0049] The center battery unit BY1 includes multiple batteries (center batteries) B1 arranged in a row in the front-to-rear direction, and these batteries B supply power to the motor M. The motor M receives power from the center battery unit BY1 to drive the rear wheels 8. Although not shown, the center battery unit BY1 may also include a battery case that houses the center battery B1, a sensor that detects the temperature of the center battery B1, a heat exchanger that adjusts the temperature of the center battery B1, and the like.

[0050] The center battery B1 is composed of chargeable and dischargeable secondary batteries (battery cells). The center battery B1 may be, for example, a lithium-ion battery, an all-solid-state battery, or another type of secondary battery. The center battery B1 may also be a so-called battery cell, or a battery pack containing multiple battery cells. In the figure, the center battery B1 is shown as a rectangular parallelepiped to approximate its shape, but the shape of the center battery B1 is not limited to a rectangular parallelepiped. All center batteries B1 are the same.

[0051] Since the motor M drives the rear wheels 8, it is located at the rear of the vehicle body, specifically behind the center battery unit BY1. The center battery unit BY1 is configured so that it becomes heavier as it moves away from the motor M, i.e., toward the front. For example, as shown in FIG. 3, the center battery unit BY1 is configured so that the width (lateral dimension) of the center battery unit BY1 increases as it moves away from the motor M in a top view of the vehicle. Specifically, five center batteries B1 that make up the center battery unit BY1 are lined up in the front-to-rear direction, with the longitudinal direction being the front-to-rear direction. The frontmost center batteries B1 are lined up in three in the vehicle width direction. The second-nearest center batteries B1 are lined up in two in the vehicle width direction. The third, fourth, and rearmost center batteries B1 from the front are lined up in a single row in the front-to-rear direction, and therefore are not lined up in the vehicle width direction.

[0052] Furthermore, the center battery unit BY1 is configured so that its vertical dimension increases with increasing distance from the motor M. As shown in FIG. 5, the frontmost center battery B1 and the second-from-the-front center battery B1 are arranged in fours vertically. The third-from-the-front and third-from-the-front center batteries B1 are arranged in threes vertically. The rearmost center battery B1 is arranged in twos vertically. The number of center batteries B1 arranged in the vertical direction can also be referred to as the number of rows or stacks.

[0053] In other words, the center battery B1 is arranged so that the width of the center battery unit BY1 increases with increasing distance from the motor M, and the vertical dimension of the center battery unit BY1 increases with increasing distance from the motor M. As a result, the front end of the center battery unit BY1 is the heaviest, and the rear end of the center battery unit BY1 is the lightest. The weight of the center battery unit BY1's front-to-rear middle portion is intermediate between the front and rear ends.

[0054] The passenger seat 30 and the driver's seat 40 are located to the sides of the center battery B1, which is located third, fourth, and rearmost from the front of the center battery unit BY1. Meanwhile, the frontmost and second-to-front center batteries B1 of the center battery unit BY1 are located forward of the passenger seat 30 and the driver's seat 40. That is, the center batteries B1 are not aligned in the vehicle width direction in the portion of the center battery unit BY1 between the passenger seat 30 and the driver's seat 40, so the width is set narrower than the portion of the center battery unit BY1 forward of the passenger seat 30 and the driver's seat 40. The width of the center battery unit BY1 corresponds to the width of the tunnel section 11, and becomes narrower toward the rear.

[0055] In addition, the center batteries B1 located at the front and second from the front of the center battery unit BY1 have the most tiers, the third and fourth from the front have the next fewest tiers, and the rearmost center battery B1 has the fewest tiers. As a result, the height of the center battery unit BY1 increases toward the front, corresponding to the bulging height of the tunnel section 11.

[0056] The number of center batteries B1 constituting the center battery unit BY1, the number of rows in the front-rear direction, and the number of rows are not limited to those described above and can be set arbitrarily. That is, the row and row number of center batteries B1 may be set so that the center battery unit BY1 becomes heavier as it moves away from the motor M. For example, the row number in the front-rear direction may be any number greater than or equal to two, and the row number may be any number greater than or equal to one.

[0057] The passenger-side battery unit BY2 is disposed on the floor panel 10 forward of the cushion portion 31 of the passenger seat 30. A passenger-side battery arrangement portion (third battery arrangement portion) 11B in which the passenger-side battery unit BY2 can be disposed is provided in front of the passenger seat 30 as a portion for arranging the passenger-side battery unit BY2. Specifically, the passenger-side battery unit BY2 is disposed in the rear portion of the floor panel 10 on the passenger side, and the front portion of the floor panel 10 on the passenger side is configured as a foot rest 10a on which the feet of an occupant seated in the passenger seat 30 can rest. An occupant with an average build rarely assumes a posture in which their feet are placed directly in front of the cushion portion 31 of the passenger seat 30, but rather often stretches their legs out and places their feet slightly forward and away from the cushion portion 31. In this embodiment, the passenger seat side battery unit BY2 is not located forward of the cushion portion 31, and the foot rest portion 10a is provided, so that the comfort of the occupant seated in the passenger seat 30 can be improved while the battery B2 is mounted on the passenger seat 30 side.

[0058] Regarding the positional relationship between the passenger-side battery unit BY2 and the hip point HP1 of the occupant seated in the driver's seat 40, the passenger-side battery unit BY2 is disposed forward of the hip point HP1 of the occupant seated in the driver's seat 40. In FIG. 3, the center of gravity of the passenger-side battery unit BY2 is indicated by point P1, and the center of the vehicle (center in the front-rear and width directions) is indicated by point P2. In a top view, the hip point HP1 of the occupant seated in the driver's seat 40, the vehicle center (point P2), and the center of gravity of the passenger-side battery unit BY2 (point P1) are disposed on the same straight line (imaginary line L). This imaginary line L is inclined in a top view so that it is positioned further rearward as it moves toward the driver's seat 40.

[0059] The passenger-side battery unit BY2 includes a plurality of passenger-side batteries B2 similar to the center battery B1 that constitutes the center battery unit BY1. The passenger-side batteries B2 also serve to supply power to the motor M. The passenger-side battery unit BY2 may include a battery case, a sensor that detects the temperature of the passenger-side batteries B2, a heat exchanger that adjusts the temperature of the passenger-side batteries B2, and the like.

[0060] The upper end of the passenger-side battery unit BY2 is positioned below the upper surface of the front end of the cushion portion 31 of the passenger seat 30. The passenger-side battery unit BY2 is configured so that its height decreases as it moves toward the front. That is, three passenger-side batteries B2 are arranged in the front-to-rear direction with their longitudinal direction aligned with the vehicle width direction. The frontmost passenger-side battery B2 has one tier, while the second-to-front and rearmost passenger-side batteries B2 have two tiers. Of the two tiers of passenger-side batteries B2, the height of the upper end of the upper passenger-side battery B2 is lower than the upper surface of the front end of the cushion portion 31 of the passenger seat 30. This prevents the passenger-side battery unit BY2 from coming into contact with the backs of the thighs of the passenger sitting in the passenger seat 30, thereby improving the comfort of the passenger sitting in the passenger seat 30. The passenger-side battery B2 is covered by a battery cover 50 (shown only in FIG. 4 ). The battery cover 50 may be made of a flexible material such as cloth or synthetic leather, or may be made of a hard resin material. The battery cover 50 may be a component that constitutes part of the passenger-side battery unit BY2.

[0061] Of the passenger-side batteries B2, the frontmost passenger-side battery B2 is a front battery, and the rearmost passenger-side battery B2 is a rear battery. The rearmost passenger-side battery B2 is two-tiered, while the frontmost passenger-side battery B2 is one-tiered. Therefore, when comparing the heights of the upper ends, the rearmost passenger-side battery B2 is higher than the frontmost passenger-side battery B2.

[0062] In this embodiment, the hip point HP2 of the occupant sitting in the passenger seat 30 is set lower than the upper surface of the rear side of the passenger-side battery B2. That is, the shape of the legs of the occupant sitting in the passenger seat 30 increases as they move from the hip point HP2 toward the knees. By making the upper surface of the rear side of the passenger-side battery B1 higher than the hip point HP2 to accommodate this shape of the legs, the amount of the passenger-side battery B1 that can be installed can be increased.

[0063] The number of passenger-side batteries B2 constituting the passenger-side battery unit BY2, the number of rows in the front-rear direction, and the number of rows are not limited to those described above and can be set arbitrarily. That is, the row and number of rows of the passenger-side batteries B2 may be set so that the passenger-side battery unit BY2 becomes lower as it moves forward. For example, the number of rows in the front-rear direction may be any number equal to or greater than two, and the number of rows may be any number equal to or greater than one. The passenger-side battery B2 may have its longitudinal direction oriented in the vehicle width direction or in the front-rear direction.

[0064] The passenger-side battery unit BY2 is detachably mounted on the vehicle body, i.e., the floor panel 10. Specifically, as shown in FIG. 4 , an attachment / detachment mechanism 14 for attaching and detaching the passenger-side battery unit BY2 is provided on the passenger-side seat 30 side of the floor panel 10. The attachment / detachment mechanism 14 includes a main body 14a fixed to the passenger-side seat 30 side of the floor panel 10 and a locking portion 14b provided on the main body 14a and locking to the passenger-side battery unit BY2. The locking portion 14b is movable between a locked position where it is locked to the passenger-side battery unit BY2 and an unlocked position where it is disengaged from the passenger-side battery unit BY2. With the passenger-side battery unit BY2 mounted, by switching the locking portion 14b to the locked position, the passenger-side battery unit BY2 is fixed to the floor panel 10 so that it will not move due to vibrations during driving, etc. On the other hand, when the passenger-seat side battery unit BY2 is to be removed, the locking portion 14b is switched from the locking position to the unlocking position.

[0065] The attachment / detachment mechanism 14 for the passenger-side battery unit BY2 may be provided as needed. The structure of the attachment / detachment mechanism 14 is not limited to the structure described above, and may be a structure in which the passenger-side battery unit BY2 is attached to the floor panel 10 or a bracket (not shown) by fastening with screws or bands, or an engagement structure using engagement claws.

[0066] For example, if weight reduction is prioritized over the cruising range of the electric vehicle 1, the electric vehicle 1 can be driven with the passenger-side battery unit BY2 removed. The passenger-side battery unit BY2 can also be removed to increase the living space of the passenger seat 30. The passenger-side battery unit BY2 may also be removed if the front-to-rear and left-to-right weight balance is prioritized over the cruising range of the electric vehicle 1. In this case, the passenger-side battery unit BY2 can be used to adjust the weight balance of the electric vehicle 1, so the passenger-side battery unit BY2 can be used as part of a weight balance adjustment means. Only some of the multiple passenger-side batteries B2 that make up the passenger-side battery unit BY2 may be detachable. The multiple passenger-side batteries B2 that make up the passenger-side battery unit BY2 may be divided into multiple groups, and each group may be detachable separately.

[0067] As shown in Figures 3 and 5, the motor M is attached to a subframe 80 provided on the rear lower part of the vehicle body, and is disposed in a central portion in the vehicle width direction below the inclined panel 16 and the rear panel 17. The motor M is disposed so that its output shaft M1 is oriented in the front-to-rear direction. In this embodiment, the output shaft M1 of the motor M protrudes rearward. The front portion of the motor M is disposed within the tunnel section 11. Since the motor M is mounted as far forward as possible in this manner, the motor M is disposed so as to overlap at least a portion of the back section 32 of the passenger seat 30 in a side view shown in Figure 4. For example, the motor M can be disposed so that the lower portion of the back section 32 and the front portion of the motor M overlap in a side view. This allows the motor M to be positioned closer to the center of the vehicle.

[0068] The vehicle body structure A is provided with a left drive shaft 60 and a right drive shaft 61 that are provided behind a tunnel portion 11 of the floor panel 10 and transmit the rotational force of a motor M to the rear wheels 8, which are drive wheels. The left drive shaft 60 and the right drive shaft 61 extend in the vehicle width direction. The motor M is provided between the left drive shaft 60 and the right drive shaft 61 and the tunnel portion 11. Therefore, the motor M is positioned closer to the center of the vehicle in the longitudinal direction than the drive shafts 60 and 61. Although not shown, if the motor is provided on the front side and drives the front wheels 7, the left drive shaft and the right drive shaft may be provided in front of the tunnel portion 11.

[0069] The vehicle body structure A also includes a transmission 62 and a differential gear box 63. The transmission 62 and the differential gear box 63 are attached to a subframe 80. The transmission 62 and the differential gear box 63 are disposed behind the motor M and on the driver's seat 40 side of the vehicle body. The rotational force of the output shaft M1 of the motor M is input to the transmission 62 via a gear 64. The rotational force of the output shaft M1 extending in the front-rear direction is converted into rotational force about an axis extending in the vehicle width direction via the gear 64 and input to the transmission 62. The transmission 62 is a transmission or a reduction gear. When the transmission 62 is a transmission, it may be a stepped transmission or a continuously variable transmission. The transmission 62 and the differential gear box 63 may be integrated, or a single gear box may house gears constituting the transmission and gears constituting the differential mechanism. Furthermore, the motor M and the transmission 62 may be modularized. Although not shown, if the motor M is provided on the front side of the vehicle body to drive the front wheels 7, the transmission 62 and the differential gear box 63 may be provided in front of the tunnel section 11.

[0070] The rotational force of the motor M output from the transmission 62 is transmitted to the left and right rear wheels 8 via a differential mechanism (not shown) housed in a differential gear box 63 and drive shafts 60 and 61 .

[0071] As shown in FIG. 3, the rear right battery unit BY3 is provided behind the driver's seat 40. An inclined panel 16 is located behind the driver's seat 40, and a rear right battery mounting section (first battery mounting section) 11C in which the rear right battery unit BY3 can be mounted is provided behind the inclined panel 16 (outside the passenger compartment R3). The rear right battery unit BY3 includes a plurality of rear right batteries B3 similar to the center battery B1 that constitutes the center battery unit BY1. The rear right batteries B3 also serve to supply power to the motor M. The rear right battery unit BY3 may include a battery case, a sensor for detecting the temperature of the rear right batteries B3, a heat exchanger for regulating the temperature of the rear right batteries B3, and the like.

[0072] The rear-left battery unit BY4 is provided behind the passenger seat 30. An inclined panel 16 is located behind the passenger seat 30, and a rear-left battery mounting section (first battery mounting section) 11D in which the rear-left battery unit BY4 can be mounted is provided behind the inclined panel 16 (outside the passenger compartment R3). The rear-left battery unit BY4 includes a plurality of rear-left batteries (rear batteries) B4 similar to the center battery B1 that constitutes the center battery unit BY1. The rear-left batteries B4 also serve to supply power to the motor M. The rear-left battery unit BY4 may include a battery case, a sensor that detects the temperature of the rear-left batteries B4, a heat exchanger that adjusts the temperature of the rear-left batteries B4, and the like.

[0073] The rear right battery mounting section 11C and the rear left battery mounting section 11D are provided in front of the transmission 62 when the transmission 62 is used as a reference. The rear right battery mounting section 11C and the rear left battery mounting section 11D are provided on both sides of the motor M in the vehicle width direction. In other words, the motor M is disposed between the rear right battery B3 and the rear left battery B4, and the rear right battery B3 and the rear left battery B4 are disposed so as to at least partially overlap the motor M in a side view. The rear right battery B3 and the rear left battery B4 can also be called side batteries because they are provided on both sides of the motor M in the vehicle width direction.

[0074] The number of rear right batteries B3 constituting the rear right battery unit BY3, the number of rows in the front-rear direction, and the number of tiers can be set arbitrarily. The number of rear left batteries B4 constituting the rear left battery unit BY4, the number of rows in the front-rear direction, and the number of tiers can also be set arbitrarily. The rear right battery B3 and the rear left battery B4 may have their longitudinal directions facing either the width direction of the vehicle or the front-rear direction. The rear right battery unit BY3 and the rear left battery unit BY4 are detachable.

[0075] (Effects of the embodiment) As described above, in the body structure A of the electric vehicle 1 according to this embodiment, the floor panel 10 is located between the front wheels 7 and the rear wheels 8, i.e., in the longitudinal center of the vehicle, and the tunnel section 11 of this floor panel 10 is located in the transverse center of the vehicle. Therefore, by accommodating the center battery unit BY1 within the tunnel section 11, it is possible to position heavy objects closer to the center of the vehicle. This reduces the yaw moment of inertia. Furthermore, because the center battery unit BY1 is configured to become heavier with increasing distance from the motor M, the vehicle's longitudinal weight distribution is less likely to be biased toward the front or rear.

[0076] Furthermore, by arranging the passenger-side battery unit BY2 further forward in the vehicle than the cushion portion 31 of the passenger seat 30, space is secured for the occupant seated in the passenger seat 30. The passenger-side battery unit BY2 is heavy because it supplies power to the motor M, but because the passenger-side battery B2 is arranged further forward in the vehicle than the hip point HP1 of the occupant seated in the driver's seat 40, the center of gravity of the vehicle when there is no occupant seated in the passenger seat 30 moves closer to the center of the vehicle, and as a result, the yaw moment of inertia is reduced.

[0077] Furthermore, when viewed in the vehicle longitudinal direction, the tunnel portion 11 of the floor panel 10, the motor M, and the drive shafts 60 and 61 are aligned in this order. Therefore, the motor M, which is a heavy object, is closer to the vehicle longitudinal center than the drive shafts 60 and 61. Furthermore, the rear right battery unit BY3 and the rear left battery unit BY4 at least partially overlap with the motor M in a side view, so that they are closer to the vehicle longitudinal center than the drive shafts 60 and 61. Therefore, the layout including the motor M, the rear right battery unit BY3, and the rear left battery unit BY4 is advantageous for yaw inertia moment. In addition, by locating the rear right battery unit BY3 and the rear left battery unit BY4 in the space forward of the drive shafts 60 and 61, it is possible to ensure a sufficient battery capacity.

[0078] The above-described embodiment is merely illustrative in all respects and should not be construed as limiting. Furthermore, all modifications and variations within the scope of the claims are within the scope of the present invention. For example, only one of the rear right battery unit BY3 and the rear left battery unit BY4 may be provided. Furthermore, the motor M may be provided either to the left or to the right of the vehicle body. Furthermore, the motor M may be disposed so that its output shaft M1 faces the vehicle width direction. [Industrial Applicability]

[0079] As described above, the present disclosure can be used in an electric vehicle equipped with a drive motor and a battery. [Explanation of symbols]

[0080] 1. Electric vehicles 10 floors 10a Footrest 11 Tunnel section 11A Center battery location (first battery location) 11B Passenger side battery location (third battery location) 11C Rear right battery location (first battery location) 20 Dash Panel 30 Passenger seat (left seat) 31 Cushion part 32 Back section 40 Driver's seat (right seat) 60, 61 Drive shaft A. Body structure BY1 center battery unit B1 Center battery Medium motor

Claims

1. An electric vehicle, a tunnel portion provided in a center portion of the floor panel in a vehicle width direction, the tunnel portion bulging upward and extending in a vehicle front-rear direction; A battery unit including a plurality of batteries housed in the tunnel portion and arranged in a line in the front-rear direction of the vehicle; a motor provided at the front or rear of the battery unit and configured to receive power from the battery and drive drive wheels; An electric vehicle, wherein the battery unit is configured to become heavier as it moves away from the motor.

2. 2. The electric vehicle according to claim 1, The battery unit is configured so that a width of the battery unit increases with increasing distance from the motor when viewed from above the vehicle.

3. 2. The electric vehicle according to claim 1, The motor is disposed so as to overlap at least a portion of a back portion of a seat provided on the floor panel in a side view of the vehicle.

4. 2. The electric vehicle according to claim 1, a drive shaft that transmits the rotational force of the motor to the drive wheels; The electric vehicle, wherein the motor is disposed closer to a center of the vehicle in a front-rear direction than the drive shaft.

5. 3. The electric vehicle according to claim 2, A left seat and a right seat are provided on the left and right sides of the tunnel portion in the floor panel, respectively. An electric vehicle, wherein a width of a portion of the battery unit between the left seat and the right seat is set to be narrower than a width of a portion of the battery unit forward of the left seat and the right seat.

6. 2. The electric vehicle according to claim 1, The vehicle further includes a dash panel extending upward and in a vehicle width direction from a front end portion of the floor panel, a front end portion of the battery unit is positioned rearward of the dash panel.

7. 2. The electric vehicle according to claim 1, The motor is provided behind the battery unit, The protruding height of the tunnel portion from the floor panel increases toward the front of the vehicle, The height of the battery unit increases toward the front of the vehicle so as to correspond to the bulging height of the tunnel portion.

8. 8. The electric vehicle according to claim 7, A sheet is provided on a side of the tunnel portion in the floor panel, An electric vehicle, wherein an upper end of the tunnel portion is positioned higher than an upper surface of a cushion portion of the seat.

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