Abstract:
An electric vehicle wherein at least part of a cell unit is provided along an inclined part of a rear dividing wall. A bottom end of the cell unit is positioned lower than the hip point of a passenger. As seen from the vehicle-width direction, motor mounts are positioned so that the top part of the cell unit and part of the motor mounts overlap in the vertical direction of the electric vehicle.

Description:
TECHNICAL FIELD 
       [0001]    The present invention relates to an electric vehicle having a battery unit and a motor. 
       BACKGROUND ART 
       [0002]    According to an electric vehicle disclosed in Japanese Laid-Open Patent Publication No. 09-309343 (hereinafter referred to as “JP 09-309343 A”), a battery cluster 20 is disposed below a driver seat 6 (FIG. 2). 
         [0003]    A vehicle 1000 disclosed in U.S. Patent Application Publication No. 2006/0096797 (hereinafter referred to as “US 2006/0096797 A1”) has a first battery pack 1900 that is a 12-volt lead storage battery, and a second battery pack 2000 that is a lithium ion battery ([0032], [0033]). The first battery pack 1900 is disposed in an engine compartment ([0033]). The second battery pack 2000 is provided beneath the base of a front passenger seat 1120 of the vehicle 1000 ([0034]). 
         [0004]    According to an electric vehicle disclosed in Japanese Laid-Open Patent Publication No. 08-002405 (hereinafter referred to as “JP 08-002405 A”), a lead battery 25 is disposed above a fuel tank 24, and a sodium-sulfur battery 28 is disposed behind a partition 27 (FIG. 4, FIG. 5, [0011], [0012]). 
         [0005]    According to U.S. Patent Application Publication No. 2007/0089442 (hereinafter referred to as “US 2007/0089442 A1”), a rear air-conditioning unit 2000 and a battery pack 3000 are provided on a floor panel 4000 and below an upper back panel 5000 (FIG. 1, [0052]). The battery pack 3000 is substantially in the shape of a rectangular parallelepiped (FIGS. 1 and 2). 
         [0006]    According to a vehicle 1 disclosed in U.S. Patent Application Publication No. 2011/0132676 (hereinafter referred to as “US 2011/0132676 A1”), the front side of a battery 12 that supplies electric power to a motor 11 is disposed forwardly of a dash panel 18, and the rear side of the battery 12 is disposed in a tunnel 22 that extends in a longitudinal direction of the vehicle (Abstract, FIGS. 1 and 2). 
       SUMMARY OF INVENTION 
       [0007]    The above documents propose various layouts with respect to battery units such as batteries, etc. However, there is still room for improvement in the proposed layouts. For example, according to JP 09-309343 A, since the battery cluster 20 is disposed below (immediately below) the driver seat 6 (FIG. 2), a limitation is imposed on efforts to lower the position of the driver seat 6 itself. Therefore, it is difficult to lower the center of gravity of the overall vehicle while the vehicle is being driven, thus leading to roll-axis moments or the like that impede efforts to enhance driving performance. 
         [0008]    According to the vehicle 1000 disclosed in US 2006/0096797 A1, the second battery pack 2000 is provided beneath the base of the front passenger seat 1120 of the vehicle 1000 (FIG. 2, FIG. 3, [0034]). Consequently, the vehicle 1000 has the same limitations or restrictions as the vehicle disclosed in JP 09-309343 A. 
         [0009]    According to JP 08-002405 A, the lead battery 25 and the sodium-sulfur battery 28 are disposed in the positions shown in FIGS. 4 and 5 of the reference. For example, the lead battery 25 and the sodium-sulfur battery 28 are located in relatively higher positions compared to the seated position of the passenger. Therefore, it is difficult to lower the center of gravity of the overall vehicle while the vehicle is being driven, leading to roll-axis moments or the like that impede efforts to enhance driving performance. 
         [0010]    According to US 2007/0089442 A1, the battery pack 3000, which is in the shape of a rectangular parallelepiped, is disposed on the floor panel 4000 and below the upper back panel 5000 and the rear air-conditioning unit 2000 (FIG. 1). In particular, FIG. 1 of US 2007/0089442 A1 shows that the front part (left side of FIG. 1) of the upper back panel 5000 is inclined along a rear seat back 1010, whereas the battery pack 3000 is disposed in an uninclined position. Therefore, a dead space is created on a front side (left side in FIG. 1) of the battery pack 3000 between the battery pack 3000 and the upper back panel 5000. 
         [0011]    According to US 2011/0132676 A1, the front side of the battery 12 is disposed forwardly of the dash panel 18, and the rear side of the battery 12 is disposed in a tunnel 22 that extends in the longitudinal direction of the vehicle (see Abstract, and FIGS. 1 and 2). Consequently, there is a tendency for the battery 12 to impair occupant comfort in the vehicle, or to present obstacles to efforts to make the vehicle compact. 
         [0012]    The present invention has been made in view of the aforementioned problems. An object of the present invention is to provide an electric vehicle, which enables at least one of driving performance, compactness, and occupant comfort to be improved. 
         [0013]    According to the present invention, there is provided an electric vehicle having two seats, including a battery unit, a motor configured to drive a rear wheel, and motor mounts disposed behind the battery unit and supporting the motor securely in place. The electric vehicle further comprises a rear partition defining a passenger compartment behind a rear surface of an occupant seat, wherein the rear partition includes a slanted portion, which is inclined progressively rearward of the electric vehicle in an upward direction, the battery unit has at least a portion disposed along the slanted portion of the rear partition, the battery unit has a lower end disposed below a hip point of an occupant, and the motor mounts are disposed such that an upper portion of the battery unit and a portion of the motor mounts overlap each other in a vertical direction of the electric vehicle as viewed transversely across the electric vehicle. 
         [0014]    According to the present invention, the lower end of the battery unit is disposed below the hip point, thereby making the center of gravity of the electric vehicle lower, as compared with a situation in which the lower end of the battery box is disposed above the hip point. Consequently, it is possible for the center of gravity of the electric vehicle to be positioned close to the hip point in the vertical direction. Thus, the occupant of the vehicle is given a feeling of oneness with the electric vehicle and a nimble sense of maneuverability when driving the electric vehicle. Further, assuming that the hip point can be lowered, the height of the electric vehicle can also be lowered, resulting in a reduction in air resistance and thereby minimizing fuel consumption or electric power consumption. 
         [0015]    According to the present invention, in addition, the rear partition includes the slanted portion, which is inclined progressively rearward of the electric vehicle in an upward direction, and at least a portion of the battery unit is disposed along the slanted portion of the rear partition. Consequently, it is possible to locate the battery unit close to an occupant seat in the longitudinal direction of the electric vehicle. In addition, the motor mounts are disposed such that an upper portion of the battery unit and a portion of the motor mounts overlap each other in a vertical direction of the electric vehicle as viewed transversely across the electric vehicle (e.g., the upper portion of the battery unit and the portion of the motor mounts overlap each other as viewed in plan). Thus, the motor mounts and the motor fixed to the motor mounts can be located close to the occupant seat in the longitudinal direction of the electric vehicle. Stated otherwise, the amount of dead space behind the rear partition can be reduced. Consequently, the electric vehicle can be made compact, or the space in the passenger compartment can be increased by the reduced dead space, thereby enhancing occupant comfort. 
         [0016]    The battery unit may be disposed outside of the passenger compartment, and the battery unit may have a portion fixed to the rear partition. In this manner, it is possible to increase the rigidity of the rear partition (as well as the vehicle body) by taking advantage of the rigidity of the battery unit itself. 
         [0017]    The battery unit may supply electric power to the motor. In addition, the battery unit, the motor, and an inverter configured to control supply of electric power from the battery unit to the motor may be disposed in one space. Normally, the motor, the battery unit, and the inverter are high-voltage devices, respectively. By disposing such high-voltage devices close to each other, electric power efficiency can be increased. 
         [0018]    The inverter may be disposed behind the battery unit and above the motor. When disposed in this manner, the motor, the battery unit, and the inverter are housed in a compact fashion. 
         [0019]    The battery unit may be constructed integrally with the inverter. In accordance with this feature, it is possible to dispense with electric power cables that interconnect the battery unit and the inverter. 
         [0020]    The battery unit may include a cover, and the cover may be installed in a direction that is the same as a direction in which the inverter is installed. In accordance with this feature, the process of installing the inverter and operations to connect electric wires thereto can be facilitated. 
     
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         [0021]      FIG. 1  is a side elevational view, partially omitted from illustration, of an electric vehicle according to an embodiment of the present invention; 
           [0022]      FIG. 2  is a plan view, partially omitted from illustration, of the electric vehicle; 
           [0023]      FIG. 3  is a bottom view, partially omitted from illustration, of the electric vehicle; 
           [0024]      FIG. 4  is an enlarged fragmentary perspective view, partially omitted from illustration, of the electric vehicle; 
           [0025]      FIG. 5  is a rear elevational view, partially omitted from illustration, of the electric vehicle; 
           [0026]      FIG. 6  is a perspective view of a motor and portions around the periphery thereof; 
           [0027]      FIG. 7  is an enlarged fragmentary plan view, partially omitted from illustration (including a battery box), of the electric vehicle; 
           [0028]      FIG. 8  is an enlarged fragmentary side elevational view, partially omitted from illustration, of the electric vehicle; 
           [0029]      FIG. 9  is an enlarged fragmentary plan view illustrating a supporting structure for the battery box; 
           [0030]      FIG. 10  is an enlarged fragmentary side elevational view showing a modified rear partition; 
           [0031]      FIG. 11  is an enlarged fragmentary side elevational view showing a first modification of the battery box according to the embodiment; and 
           [0032]      FIG. 12  is an enlarged fragmentary side elevational view showing a second modification of the battery box according to the embodiment. 
       
    
    
     DESCRIPTION OF EMBODIMENTS 
     A. Embodiment 
     1. Description of Overall Arrangement 
     [1-1. Overall Arrangement] 
       [0033]      FIG. 1  is a side elevational view, partially omitted from illustration, of an electric vehicle  10  (hereinafter also referred to as a “vehicle  10 ”) according to an embodiment of the present invention.  FIG. 2  is a plan view, partially omitted from illustration, of the electric vehicle  10 .  FIG. 3  is a bottom view, partially omitted from illustration, of the electric vehicle  10 .  FIG. 4  is an enlarged fragmentary perspective view, partially omitted from illustration, of the electric vehicle  10 .  FIG. 5  is a rear elevational view, partially omitted from illustration, of the electric vehicle  10 . The vehicle  10 , which is an electric car (battery car) in a narrow sense, includes a motor  12  and an electric power system  14  having a battery box  16  (battery unit). As described later, the vehicle  10  may be another type of electric vehicle apart from an electric car, insofar as the motor  12  is included therein. 
         [0034]    The vehicle  10  is a two-seater vehicle in which a driver seat  20  and a front passenger seat  22 , each functioning as an occupant seat, are disposed adjacent to each other in a transverse direction of the vehicle, i.e., in the direction of arrows Y 1  and Y 2  in  FIG. 2 , etc. As described later, aside from a two-seater vehicle, the vehicle  10  may be another type of vehicle (as to the number of seats thereof). Although the vehicle  10  is a right-hand drive vehicle, the vehicle  10  may be a left-hand drive vehicle. 
       [1-2. Motor  12 ] 
     (1-2-1. Overview of Motor  12 ) 
       [0035]    The motor  12  serves as a drive source for generating a driving force F for the vehicle  10 , and in the present embodiment, the motor  12  drives the rear wheels  24   r . The motor  12 , which comprises a three-phase AC brushless motor, generates a driving force F for the vehicle  10  on the basis of electric power supplied from the battery box  16 . In addition, the motor  12  regenerates electric power (regenerative electric power Preg) [W] in a regenerative mode, and outputs the regenerative electric power Preg to the battery box  16  in order to charge the battery box  16 . The motor  12  may also output the regenerative electric power Preg to a 12-volt system or to various accessories, not shown. The motor  12  is combined integrally with a gearbox and is disposed coaxially with shafts  26  for the rear wheels  24   r.    
       (1-2-2. Layout of Motor  12 ) 
       [0036]      FIG. 6  is a perspective view of the motor  12  and portions around the periphery thereof.  FIG. 7  is an enlarged fragmentary plan view, partially omitted from illustration (including the battery box  16 ), of the electric vehicle  10 . As shown in  FIGS. 1 through 7 , the motor  12  is fixed to a subframe  32  by motor mounts  30   a  through  30   c  (hereinafter referred to collectively as “motor mounts  30 ”). 
         [0037]    The motor mounts  30   a  through  30   c  according to the present embodiment include three motor mounts, i.e., a left front mount  30   a , a right front mount  30   b , and a rear mount  30   c . However, the motor mounts  30   a  through  30   c  are not limited to this description, insofar as the motor mounts  30   a  through  30   c  are capable of supporting the motor  12 . 
         [0038]    As shown in  FIGS. 1 ,  2 , and  6 , etc., the left front mount  30   a  and the right front mount  30   b  as well as a portion of the battery box  16  overlap each other as viewed in plan, i.e., along the direction of arrows Z 1  and Z 2 . 
       [1-3. Electric Power System  14 ] 
     (1-3-1. Overview of Electric Power System  14 ) 
       [0039]    The electric power system  14  supplies electric power to the motor  12  and is charged with regenerative electric power Preg from the motor  12 . In addition to the battery box  16 , the electric power system  14  includes a motor controller  40  and a battery controller  42 . 
       (1-3-1-1. Battery Box  16 ) 
     (1-3-1-1-1. Overview of Battery Box  16 ) 
       [0040]      FIG. 8  is an enlarged fragmentary side elevational view, partially omitted from illustration, of the electric vehicle  10 . The battery box  16  includes a plurality of battery modules  50 , a battery tray  52 , a first battery cover  54 , and a second battery cover  56 . Although the battery box  16  basically is in the shape of a rectangular parallelepiped, as shown in  FIG. 4 , etc., the battery box  16  has a recess in which the motor controller  40  is disposed. The battery box  16  is disposed in the same space as the motor  12  and the motor controller  40  (including an inverter  90 , to be described later). The battery box  16  is constructed integrally with the motor controller  40  (see  FIG. 4 , etc.). 
       (1-3-1-1-2. Battery Modules  50 ) 
       [0041]    Each of the battery modules  50 , which serve as battery units, is an electric energy storage device (energy storage) including a plurality of battery cells, which may comprise lithium ion secondary cells, nickel hydrogen secondary cells, or capacitors. According to the present embodiment, each of the battery modules  50  comprises lithium ion secondary cells. Further, in the present embodiment, each of the battery modules  50  is substantially in the shape of a rectangular parallelepiped. A non-illustrated DC/DC converter may be connected between the battery modules  50  and the motor controller  40  (inverter  90 ) for stepping up or stepping down the output voltage of the battery modules  50  or the output voltage of the motor  12 . 
       (1-3-1-1-3. Battery Tray  52 ) 
       [0042]    The battery tray  52  is a plate-like support member made of metal or plastic that supports the battery modules  50 . As shown in  FIG. 8 , each of the battery modules  50  is fixed to the battery tray  52  by bolts  58 . 
       (1-3-1-1-4. First Battery Cover  54 , Second Battery Cover  56 ) 
       [0043]    The first battery cover  54  and the second battery cover  56  are members made of plastic or metal that cover the battery modules  50  and the battery tray  52 . The first battery cover  54  is fixed to the battery tray  52  on a front side of the battery tray  52  and is oriented in the X 2  direction, and the second battery cover  56  is fixed to the battery tray  52  on a rear side of the battery tray  52  and is oriented in the X 1  direction. The first battery cover  54  and the second battery cover  56  are fixed to the battery tray  52  by non-illustrated bolts. 
       (1-3-1-1-5. Layout of Battery Box  16 ) 
       [0044]      FIG. 9  is an enlarged fragmentary plan view illustrating a supporting structure for the battery box  16 . As shown in  FIG. 1 , etc., the battery box  16  has a lower end E 1 , which is disposed in a position below a hip point P 1  of a driver  60  as an occupant. The hip point P 1  is represented by a center (design value) of the hip of an occupant (including the driver  60 ). 
         [0045]    According to the present embodiment, the lower end E 1  of the battery box  16  is disposed in a position, which lies below not only the hip point P 1 , but also a lower end E 2  (design value) of the hip of the driver  60 . 
         [0046]    As shown in  FIGS. 1 and 4 , etc., the battery box  16  is inclined along a rear partition  72  of a metallic main frame  70  of the vehicle  10 , such that an upper portion of the battery box  16  is positioned more rearwardly (rightwardly in  FIG. 1 ) than a lower portion of the battery box  16 . 
         [0047]    The rear partition  72  is a partition (a so-called bulkhead) that defines a passenger compartment  74 , and is disposed at a position behind rearward sides of the driver seat  20  and the front passenger seat  22 . As shown in  FIGS. 1 and 4 , etc., the rear partition  72  includes a slanted portion  76 , which is inclined progressively rearward in an upward direction. 
         [0048]    As shown in  FIG. 4 , etc., the battery box  16  is fixed to the rear partition  72  and along the slanted portion  76  by a left side bracket  80   a  and a right side bracket  80   b . Thus, the battery box  16  is disposed on an outer side of the passenger compartment  74 . 
         [0049]    The battery box  16  is fixed to areas of the rear partition  72 , which comprise stiffened members  78   a ,  78   b  that are increased in rigidity due to having a substantially rectangular cross-sectional shape. The lower stiffened member  78   a  is disposed on the slanted portion  76 , whereas the upper stiffened member  78   b  is not disposed on the slanted portion  76 . The upper stiffened member  78   b  may also be disposed on the slanted portion  76 . 
         [0050]    The phrase “along the slanted portion  76 ” does not necessarily imply that the front surface of the battery box  16  lies parallel to the slanted portion  76 , but rather, implies that the front surface of the battery box  16  is of a shape more likely to protrude forwardly toward a lower part of the slanted portion  76  than if the front surface of the battery box  16  were to extend in a strictly vertical direction. 
         [0051]    As shown in  FIG. 9 , the battery box  16  is fixed in position by a left upper bracket  82   a , a right upper bracket  82   b , and a stiffener bracket  84 . More specifically, as shown in  FIG. 9 , the left upper bracket  82   a  and the right upper bracket  82   b , which are of a bent shape, have respective ends that are fixed to front portions (around central pillars  87 ) of an upper back panel  86 , respective other ends that are fixed to suspension damper housings  88 , and respective centers that are fixed to the battery tray  52 . 
         [0052]    As shown in  FIG. 9 , the stiffener bracket  84  is of a straight shape, one end of which is fixed to the left upper bracket  82   a , and another end of which is fixed to the right upper bracket  82   b . The stiffener bracket  84  increases the stiffness of a linkage that is provided between the suspension damper housings  88 , thereby preventing the battery box  16  from wobbling. 
         [0053]    The battery box  16  can be installed from below the main frame  70 . To permit the battery box  16  to be installed in this manner, the main frame  70  has an opening  89  defined in a bottom surface thereof for allowing the battery box  16  to pass therethrough. A lower cover, not shown, is disposed below the battery box  16  in order to protect the battery box  16 , etc., from mud and water splashing up from the road. 
         [0054]    The left upper bracket  82   a , the right upper bracket  82   b , and the stiffener bracket  84  are illustrated only in  FIG. 9 , and have been omitted from illustration in the other figures. 
       (1-3-1-2. Motor Controller  40 ) 
     (1-3-1-2-1. Overview of Motor Controller  40 ) 
       [0055]    The motor controller  40  serves to control electric power that is exchanged between the motor  12  and the battery box  16 , and includes an inverter  90  (see  FIG. 5 ) and a non-illustrated electronic control unit. An electric power cable (a so-called three-phase cable) is connected between the motor  12  and the motor controller  40 . 
       (1-3-1-2-2. Layout of Motor Controller  40 ) 
       [0056]    As shown in  FIGS. 2 and 4 , etc., the motor controller  40  (inverter  90 ) is fixed to a left side of the second battery cover  56  behind the second battery cover  56 . The motor controller  40  (inverter  90 ) is combined integrally with the battery box  16  (see  FIG. 4 , etc.). The motor controller  40  is fixed to the second battery cover  56  by non-illustrated bolts or the like, for example. As shown in  FIG. 4 , etc., the motor controller  40  (inverter  90 ) is disposed in the same space as the motor  12  and the battery box  16 . 
       (1-3-1-3. Battery Controller  42 ) 
     (1-3-1-3-1. Overview of Battery Controller  42 ) 
       [0057]    The battery controller  42  serves to control electric power that is exchanged between the battery box  16  and a non-illustrated external power supply. The battery controller  42  includes a charger and an electronic control unit, neither of which are shown. 
       (1-3-1-3-2. Layout of Battery Controller  42 ) 
       [0058]    As shown in  FIGS. 2 and 4 , etc., the battery controller  42  is fixed to a right side of the second battery cover  56  behind the second battery cover  56 . The battery controller  42  is constructed integrally with the battery box  16 , and is disposed adjacent to the motor controller  40  (see  FIG. 4 , etc.). The battery controller  42  is fixed to the second battery cover  56  by non-illustrated bolts or the like, for example. As shown in  FIG. 4 , etc., the battery controller  42  is disposed in the same space as the motor  12 , the battery box  16 , and the motor controller  40  (inverter  90 ). 
       2. Advantages of the Present Embodiment 
       [0059]    In the foregoing manner, according to the present embodiment, as described above, the lower end E 1  of the battery box  16  (battery unit or cell cluster) is disposed below the hip point P 1 , thereby making the center of gravity of the vehicle  10  lower compared with the lower end E 1  of the battery box  16 , which is disposed above the hip point P 1 . Consequently, it is possible to position the center of gravity of the vehicle  10  close to the hip point P 1 . Hence, the occupant of the vehicle  10  is given a feeling of oneness with the vehicle  10  and a nimble sense of maneuverability when driving the vehicle  10 . Further, assuming that the hip point P 1  can be lowered, the height of the vehicle  10  can also be lowered, resulting in a reduction in air resistance and thereby minimizing electric power consumption. 
         [0060]    According to the present embodiment, in addition, the rear partition  72  includes the slanted portion  76 , which is inclined progressively rearward in an upward direction, and the battery box  16  is disposed along the slanted portion  76 . Therefore, it is possible to locate the battery box  16  close to the driver seat  20  and the front passenger seat  22  (occupant seats) in the longitudinal direction of the vehicle  10 . In addition, the motor mounts  30   a ,  30   b  are disposed such that an upper portion of the battery box  16  and the motor mounts  30   a ,  30   b  overlap each other in the vertical direction of the vehicle  10  as viewed transversely across the vehicle  10  (more specifically, the upper portion of the battery box  16  and a portion of the motor mounts  30   a ,  30   b  overlap each other as viewed in plan). Therefore, it is possible to position the motor mounts  30   a ,  30   b  as well as the motor  12  that is supported thereon close to the driver seat  20  and the front passenger seat  22  (occupant seat) along the longitudinal direction of the vehicle  10 . Stated otherwise, the amount of dead space behind the rear partition  72  can be reduced. Consequently, the vehicle  10  can be made compact, or the space in the passenger compartment  74  can be increased by the reduced dead space, thereby enhancing occupant comfort. 
         [0061]    According to the present embodiment, the battery box  16  is disposed outside of the passenger compartment  74 , and includes a portion that is fixed to the rear partition  72  (see  FIGS. 4 ,  9 , etc.). In this manner, it is possible to increase the rigidity of the rear partition  72  (as well as the vehicle body) by taking advantage of the rigidity of the battery box  16  itself. 
         [0062]    According to the present embodiment, the battery box  16  supplies electric power to the motor  12 , and the motor  12 , the battery box  16 , and the inverter  90  are disposed in the same space (see  FIG. 4 , etc.). Normally, the motor  12 , the battery box  16 , and the inverter  90  are high-voltage devices, respectively. By disposing such high-voltage devices close to each other, electric power efficiency can be increased. 
         [0063]    According to the present embodiment, the inverter  90  is disposed behind the battery box  16  and above the motor  12  (see  FIGS. 2 ,  4 , etc.). When disposed in this manner, the motor  12 , the battery box  16 , and the inverter  90  are housed in a compact fashion. 
         [0064]    According to the present embodiment, the battery box  16  is constructed integrally with the motor controller  40  (inverter  90 ) (see  FIG. 4 , etc.). In accordance with this feature, it is possible to dispense with electric power cables that interconnect the battery box  16  and the inverter  90 . 
         [0065]    According to the present embodiment, the second battery cover  56  is installed in a direction that is the same as the direction in which the motor controller  40  (inverter  90 ) is installed (see  FIG. 4 , etc.). In accordance with this feature, the process of installing the inverter  90  and operations to connect electric wires (not shown) thereto can be facilitated. 
       B. Modifications 
       [0066]    The present invention is not limited to the above embodiment, but may employ various arrangements on the basis of the disclosure of the present description. For example, the following arrangements may be employed in the present invention. 
         [0000]    1. Electric Vehicle  10  (Object to which the Present Invention is Applied) 
         [0067]    In the above embodiment, the vehicle  10  is a two-seater type of vehicle. However, the vehicle  10  may be of any type (as to the number of seats), insofar as attention is focused on the positional relationship between the motor  12  (motor mounts  30   a  through  30   c ) and the battery box  16 , or the positional relationship between the rear partition  72  and the battery box  16 . For example, the vehicle  10  may be a one-seater, a three-seater, or a four-seater type of vehicle or the like. Stated otherwise, the number of seats on the vehicle  10  may be one or three or more. 
         [0068]    In the above embodiment, the battery box  16  (battery unit) is mounted on the electric vehicle  10 , which is a battery car in a narrow sense. However, from the standpoint of the layout of the motor  12  and the battery box  16 , the present invention is applicable to other uses. For example, the present invention may be applied to other types of electric vehicles  10  (e.g., a hybrid vehicle having a non-illustrated engine as a drive source in addition to the motor  12 , or a fuel cell vehicle). 
       2. Motor  12   
       [0069]    In the above embodiment, the motor  12  comprises a three-phase AC brushless motor. However, the motor  12  is not limited to such a motor. Although the motor  12  is a brushless motor in the above-described embodiment, the motor  12  may be a brush motor. 
         [0070]    In the above embodiment, the motor  12  is used to drive the rear wheels  24   r . However, the motor  12  may be used to drive front wheels  24   f , insofar as the battery box  16  (battery unit) can be inclined and the motor mounts  30   a  through  30   c  can be placed in a space below the inclined battery box  16 . From the same standpoint, the motor  12  need not necessarily be a motor that is used to drive wheels, but may be a motor for use in any of other devices (e.g., an air compressor or an air conditioner that is mounted in the vehicle  10 ). Alternatively, the motor  12  may be a motor that is used in various apparatus such as industrial machines (e.g., manufacturing apparatus, machine tools, or elevators), home electric appliances (e.g., washing machines, cleaners, air conditioners, or refrigerators), or the like. 
       3. Motor Mounts  30   
       [0071]    In the above embodiment, the motor  12  is supported on three motor mounts  30   a  through  30   c . However, insofar as the motor  12  can be supported, the number of motor mounts  30  is not limited to three. 
         [0072]    In the above embodiment, the front motor mounts  30   a ,  30   b  and an upper portion of the battery box  16  overlap each other as viewed in plan (see  FIGS. 1 ,  2 ,  7 , etc.). However, from the standpoint of effectively utilizing the space below the slanted portion  76  of the rear partition  72  and around the lower portion of the battery box  16 , the front motor mounts  30   a ,  30   b  and the upper portion of the battery box  16  need not necessarily be superposed, insofar as the motor mounts  30   a ,  30   b  can be disposed such that the upper portion of the battery box  16  (battery unit) and the motor mounts  30   a ,  30   b  overlap each other in the vertical direction (the direction of arrows Z 1  and Z 2 ) of the vehicle  10 , as viewed transversely (in the direction of arrows Y 1  and Y 2 ) across the vehicle  10 . Stated otherwise, the front motor mounts  30   a ,  30   b  may be positioned laterally of the battery box  16  (along a transverse direction across the vehicle  10 ) as viewed in plan. 
       4. Electric Power System  14   
     [4-1. Battery Box  16  (Battery Unit, Cell Cluster)] 
       [0073]    In the above embodiment, the battery box  16  is used as a battery unit or a cell cluster. However, other battery units may be used insofar as the battery units function as an electric power supply source. For example, a fuel cell stack may be used as a battery unit. If a fuel cell stack is used, the fuel cell stack may be inclined in the same manner as with the battery box  16 . 
         [0074]    In the above embodiment, the lower end E 1  of the battery box  16  is disposed below the hip point P 1  and the lower end E 2  of the hip of the driver  60 . However, insofar as the lower end E 1  of the battery box  16  is disposed below the hip point P 1 , the lower end E 1  of the battery box  16  may be disposed above the lower end E 2  of the hip. 
         [0075]    In the above embodiment, the battery box  16  is disposed outwardly of the rear partition  72  (see  FIGS. 1 ,  4 , etc.). However, insofar as the battery box  16  (battery unit or cell cluster) is disposed along the slanted portion  76  of the rear partition  72 , the battery box  16  may be disposed inwardly of a rear partition  72   a , as shown in  FIG. 10 . 
         [0076]    In the above embodiment, the battery box  16  includes the battery modules  50 , which are disposed on both sides (front and rear sides, in terms of the orientation of the vehicle  10 ) of a principal plane of the battery tray  52  (see  FIG. 8 , etc.). However, the battery modules  50  are not limited to such a layout, insofar as the battery box  16  or the battery modules  50  can be disposed along the slanted portion  76  of the rear partition  72 . 
         [0077]      FIG. 11  is an enlarged fragmentary side elevational view showing a battery box  16   a  according to a first modification of the battery box  16  (battery unit or cell cluster) of the above-described embodiment. The battery box  16   a  comprises a plurality of battery modules  50 , which are inclined and stacked in a plurality of layers. The battery box  16   a  is disposed along the rear partition  72 , thereby making it possible to reduce the amount of dead space behind the rear partition  72 . 
         [0078]    In the above embodiment and the modification shown in  FIG. 11 , the battery box  16 , which is basically in the shape of a rectangular parallelepiped, is inclined (see  FIG. 1 , etc.). However, the battery box  16  is not limited to such an inclined layout, insofar as the battery unit can be disposed along the slanted portion  76  of the rear partition  72 . For example, the battery modules  50  may be stacked in a plurality of layers, with the front ends of the battery modules shifted more rearwardly in higher layers. 
         [0079]      FIG. 12  is an enlarged fragmentary side elevational view showing a battery cluster  130  according to a second modification of the battery box  16  (battery unit or cell cluster) of the above-described embodiment. The battery cluster  130  comprises a plurality of battery modules  50  disposed in a stepped pattern. The battery cluster  130  is disposed along the rear partition  72 , thereby making it possible to reduce the amount of dead space behind the rear partition  72 . 
         [0080]    In  FIG. 12 , each of the battery modules  50  is shifted in a stepped pattern. However, only a portion of the battery modules  50  may be shifted in this manner. For example, two lower battery modules  50  in  FIG. 12  may be kept in the same position along the longitudinal direction (the direction of arrows X 1  and X 2 ). 
         [0081]    In the above embodiment, the battery box  16  is supported at upper and side regions thereof. More specifically, the battery box  16  is supported by the left side bracket  80   a , the right side bracket  80   b , the left upper bracket  82   a , the right upper bracket  82   b , and the stiffener bracket  84  (see  FIGS. 4 ,  9 , etc.). However, insofar as the battery box  16  can be supported in place, the present invention is not limited to such a supporting structure. For example, the battery box  16  may be supported only at an upper region or on side regions thereof. Alternatively, in addition to or in place of the regions referred to above, the battery box  16  may be supported at other regions (e.g., a lower region) thereof. 
         [0082]    In the above embodiment, the battery box  16  supplies electric power to the motor  12 . However, insofar as attention is focused on the positional relationship between the motor  12  (motor mounts  30   a ,  30   b ) and the battery box  16 , in addition to the motor  12 , the battery box  16  may be used to supply electric power to other components apart from the motor  12 . Alternatively, the battery box  16  may be configured so as not to supply electric power to the motor  12 , but only to supply electric power to other components apart from the motor  12 . 
         [0000]    [4-2. Motor Controller  40  and Battery Controller  42 ] In the above embodiment, the motor controller  40  including the inverter  90  and the battery controller  42  are disposed on an outer side of the second battery cover  56 . However, concerning the layout of the battery box  16 , the motor controller  40  and the battery controller  42  are not limited to the above layout. For example, as shown in  FIG. 11 , the battery controller  42  (and the motor controller  40 ) may be disposed above the battery box  16   a.    
         [0083]    In the above embodiment, the inverter  90  is disposed behind the battery box  16  and above the motor  12  (see  FIGS. 2 ,  4 , etc.). However, insofar as attention is focused on the positional relationship between the motor  12  (motor mounts  30   a ,  30   b ) and the battery box  16 , the inverter  90  need not necessarily be disposed in the aforementioned layout. For example, the inverter  90  may be disposed above the battery box  16   a.    
         [0084]    In the above embodiment, the motor controller  40  (inverter  90 ) is constructed integrally with the battery box  16  (battery unit), without any cables being interposed between the motor controller  40  and the battery box  16 . However, insofar as attention is focused on the positional relationship between the motor  12  (motor mounts  30   a ,  30   b ) and the battery box  16 , cables may be provided if desired. Similarly, in the above embodiment, the battery controller  42  is constructed integrally with the battery box  16  (battery unit), without any cables being interposed between the battery controller  42  and the battery box  16 . However, cables may be provided if desired. 
         [0085]    In the above embodiment, the motor  12 , the battery box  16  (battery unit), the motor controller  40  (inverter  90 ), and the battery controller  42  are disposed in the same space (see  FIG. 4 , etc.). However, such a layout is not necessarily required, insofar as attention is focused on the positional relationship between the motor  12  (motor mounts  30   a ,  30   b ) and the battery box  16 . For example, the motor controller  40  (inverter  90 ) and the battery controller  42  may be disposed in a space that differs from the space in which the motor  12  and the battery box  16  (battery unit) are installed. 
         [0086]    In the above embodiment, the second battery cover  56  is installed in a direction that is the same as the direction in which the motor controller  40  (inverter  90 ) and the battery controller  42  are installed. However, such an arrangement is not necessarily required, insofar as attention is focused on the positional relationship between the motor  12  (motor mounts  30   a ,  30   b ) and the battery box  16 . 
       5. Other Features 
       [0087]    In the above embodiment, the battery box  16  is disposed along the slanted portion  76  of the rear partition  72 , and the motor mounts  30   a ,  30   b  are disposed in the space behind the battery box  16 . In addition, the motor  12  for driving the rear wheels  24   r  is supported on the motor mounts  30   a  through  30   c . However, insofar as the battery box  16  (battery unit) is inclined, and any one of the motor mounts  30   a  through  30   c  is disposed in a space beneath the battery box  16 , the same layout may be employed on the front side of the vehicle  10 . 
         [0088]    In the above embodiment, the rear partition  72  serves as part of the main frame  70 . However, the rear partition  72  may be provided separately from the main frame  70 , insofar as the rear partition  72  can function as a partition that defines the passenger compartment  74 .