Patent Publication Number: US-11654762-B2

Title: Vehicle lower structure

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     The present application claims priority to Japanese App. No. 2020-063300 filed Mar. 31, 2020, the entire content and disclosure of which is incorporated by reference herein in its entirety. 
     TECHNICAL FIELD 
     Embodiments of the present disclosure relate to a vehicle lower structure. 
     BACKGROUND ART 
     A hybrid vehicle in which an engine and a drive motor as drive sources are arranged in a vehicle front side, in which a propeller shaft is arranged under a floor panel constituting a floor surface of a cabin, and in which power from at least one of the engine and the drive motor is transmitted to drive wheels arranged in a vehicle rear side by the propeller shaft has been known. 
     The hybrid vehicle in which plural battery modules for storing electricity to be supplied to the drive motor are connected and unitized as a battery unit and in which, at a position under the floor panel, the battery unit is arranged on each side in a vehicle width direction of the propeller shaft has also been known (for example, see Patent document 1). 
     PRIOR ART DOCUMENTS 
     Patent Documents 
     
         
         [Patent document 1] Japanese Patent No. 5,483,293 
       
    
     SUMMARY 
     According to one or more embodiments a vehicle lower structure is disclosed or implemented. The vehicle lower structure can include: a drive source having a drive motor; a floor panel forming a floor surface of a cabin; and a propeller shaft extending in a vehicle longitudinal direction at a position under the floor panel to transmit power from the drive source to a drive wheel, wherein the vehicle lower structure can comprise: a first battery unit and a second battery unit that are arranged under the floor panel and separately from each other on both sides in a vehicle width direction of the propeller shaft and store electricity to be supplied to the drive motor; and right and left floor frames that are disposed on a lower surface side of the floor panel, are disposed separately from each other in the vehicle width direction, and extend in the vehicle longitudinal direction, wherein each of the right and left floor frames has a front inclined section and a width increased section, the front inclined section being inclined to an outer side in the vehicle width direction from a vehicle front side toward a vehicle rear side, and the width increased section extending linearly and rearward from the front inclined section, and a width of which is increased to the outer side in the vehicle width direction, the first battery unit and the second battery unit are arranged between the width increased sections of the right and left floor frames, and at least one battery-related electrical component, a width of which in the vehicle width direction is less than a width of each of the first battery unit and the second battery unit, is arranged between the front inclined sections of the right and left floor frames. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is a schematic view of a vehicle body to which a vehicle lower structure according to an embodiment of the present disclosure is applied. 
         FIG.  2    is a top view of the vehicle body to which the vehicle lower structure according to the embodiment of the present disclosure is applied. 
         FIG.  3    is a bottom view of the vehicle body to which the vehicle lower structure according to the embodiment of the present disclosure is applied. 
         FIG.  4    is a cross-sectional view of the vehicle body that is taken along line Y 4 -Y 4  in  FIG.  2   . 
         FIG.  5    is a cross-sectional view of the vehicle body that is taken along line Y 5 -Y 5  in  FIG.  2   . 
         FIG.  6    is a cross-sectional view of the vehicle body that is taken along line Y 6 -Y 6  in  FIG.  2   . 
         FIG.  7    is a cross-sectional view of the vehicle body that is taken along line Y 7 -Y 7  in  FIG.  2   . 
         FIG.  8    is a perspective view of a battery pack. 
         FIG.  9    is a cross-sectional view of the battery pack that is taken along line Y 9 -Y 9  in  FIG.  8   . 
     
    
    
     DETAILED DESCRIPTION 
     A description will hereinafter be made on an embodiment of the present disclosure with reference to the accompanying drawings. 
     In the hybrid vehicle in which first and second battery units are arranged under the floor panel and on both sides in the vehicle width direction of the propeller shaft, when a collision load is applied thereto from an outer side in the vehicle width direction during a lateral collision, the first and second battery units are possibly damaged. 
     Meanwhile, in a vehicle in which right and left floor frames, each of which extends linearly in a vehicle longitudinal direction, are attached to a lower surface of the floor panel between right and left front frames and right and left rear frames, it is considered to arrange the first and second battery units on an inner side in the vehicle width direction of the floor frames. 
     However, in the case where the first and second battery units, which are arranged on both sides in the vehicle width direction of the propeller shaft, are arranged on the inner side in the vehicle width direction of the floor frames, an arrangement space of the first and second battery units is reduced, which possibly reduces battery capacity of the first and second battery units. 
     In addition, in order to reduce a high-voltage harness that is electrically connected to the first and second battery units and the like, battery-related electrical components such as a DC/DC converter and an inverter are desired to be arranged near the first and second battery units in a limited space under the floor panel. 
     In view of the above, one or more embodiments of the present disclosure can have a purpose of providing a vehicle lower structure capable of arranging battery-related electrical components while securing battery capacity under a floor panel and capable of protecting first and second battery units and the battery-related electrical components in a vehicle in which, at positions under the floor panel, the first and second battery units are arranged on both sides in a vehicle width direction of a propeller shaft. 
     In order to solve at least the above problem, the inventors of the present application repeatedly made earnest analyses on configurations of a vehicle body component, a power transmission device, the first and second battery units, and the battery-related electrical components that are arranged in a lower portion of a vehicle body of the vehicle in which the first and second battery units are arranged under the floor panel and on both sides in the vehicle width direction of the propeller shaft. As a result, the inventors of the present application found a configuration capable of arranging the battery-related electrical components while securing battery capacity under the floor panel and capable of protecting the first and second battery units and the battery-related electrical components, and completed one or more embodiments of the present disclosure. 
     Embodiments of the present disclosure can provide a vehicle lower structure including: a drive source having a drive motor; a floor panel forming a floor surface of a cabin; and a propeller shaft extending in a vehicle longitudinal direction at a position under the floor panel to transmit power from the drive source to a drive wheel. The vehicle lower structure includes: a first battery unit and a second battery unit that are arranged under the floor panel and separately from each other on both sides in a vehicle width direction of the propeller shaft and store electricity to be supplied to the drive motor; and right and left floor frames that are disposed on a lower surface side of the floor panel, are disposed separately from each other in the vehicle width direction, and extend in the vehicle longitudinal direction. Each of the right and left floor frames has a front inclined section and a width increased section. The front inclined section is inclined to an outer side in the vehicle width direction from a vehicle front side toward a vehicle rear side. The width increased section extends linearly and rearward in the vehicle from the front inclined section, and a width thereof is increased to the outer side in the vehicle width direction. The first battery unit and the second battery unit are arranged between the width increased sections of the right and left floor frames. A battery-related electrical component, a width of which in the vehicle width direction is less than a width of each of the first battery unit and the second battery unit, is arranged between the front inclined sections of the right and left floor frames. 
     According to one or more embodiments of the present disclosure, the first and second battery units, which are arranged under the floor panel and are arranged on both sides in the vehicle width direction of the propeller shaft, and the right and left floor frames, which are disposed on the lower surface side of the floor panel, are provided. Each of the right and left floor frames has: the front inclined section; and the width increased section that extends linearly to the vehicle rear side from the front inclined section. The first and second battery units are arranged between the width increased sections of the right and left floor frames. The battery-related electrical component, the width of which in the vehicle width direction is less than the width of each of the first and second battery units, is arranged between the front inclined sections. 
     Since the first and second battery units are arranged at the positions under the floor panel and between the width increased sections of the right and left floor frames, compared to a case where widths of the floor frames are not increased to the outer side in the vehicle width direction, it is possible to enlarge the first and second battery units in the vehicle width direction so as to secure battery capacity of each of the first and second battery units. In addition, the first and second battery units can be protected by the right and left floor frames during a lateral collision. 
     The battery-related electrical component, the width of which in the vehicle width direction is less than the width of each of the first and second battery units, is arranged under the floor panel and between the front inclined sections of the right and left floor frames. Accordingly, it is possible to arrange the battery-related electrical component in a space that is near the first and second battery units, between the front inclined sections inclined to the outer side in the vehicle width direction, and is smaller than a space between the width increased sections of the right and left floor frames. In addition, the battery-related electrical component can be protected by the right and left floor frames during the lateral collision. 
     Therefore, in the vehicle in which the first and second battery units are arranged under the floor panel and both sides in the vehicle width direction of the propeller shaft, it is possible to arrange the battery-related electrical component under the floor panel while securing battery capacity and to protect the first and second battery units and the battery-related electrical component. 
     The battery-related electrical components are preferably a DC/DC converter and an inverter, the DC/DC converter is preferably formed such that a width thereof in the vehicle width direction is less than that of the inverter, and is preferably arranged on a vehicle front side of the inverter. 
     With this configuration, it is possible to sequentially arrange the DC/DC converter and the inverter from the vehicle front side along the front inclined section at positions between the front inclined sections of the floor frames. Therefore, it is possible to effectively use a space between the front inclined sections of the floor frames. 
     The DC/DC converter is preferably formed such that a length thereof in the vehicle longitudinal direction is greater than that of the inverter, and is preferably arranged to be superposed on the inverter in a vertical direction. 
     With this configuration, it is possible to arrange the DC/DC converter and the inverter to be compact in the vehicle longitudinal direction by effectively using the space between the front inclined sections of the floor frames. 
     A transmission, which is coupled to the engine, is preferably coupled to a vehicle front side of the propeller shaft, and the battery-related electrical component is preferably arranged between the transmission and one of the right and left floor frames. 
     With this configuration, in the case where the transmission, the width of which in the vehicle width direction is greater than that of the propeller shaft, is arranged between the front inclined sections of the right and left floor frames, it is possible to arrange the battery-related electrical component to be compact by effectively using the space between the transmission and one of the front inclined sections of the floor frames. 
     At a position between the front inclined sections of the right and left floor frames, an exhaust system component of the engine is arranged between the transmission and the other of the right and left floor frames. 
     With this configuration, it is possible to arrange the exhaust system component of the engine by effectively using the space between the transmission and the other of the front inclined sections of the floor frames. 
     Each of the right and left floor frames possibly has a rear inclined section that is inclined to an inner side in the vehicle width direction from the width increased section toward a vehicle rear side. A fuel tank is possibly arranged between the rear inclined sections of the right and left floor frames. 
     With this configuration, it is possible to arrange the fuel tank by using a space between the rear inclined sections of the floor frames and to protect the fuel tank by the right and left floor frames during the lateral collision. 
     According to the vehicle lower structure of one or more embodiments of the present disclosure, in the vehicle in which the first and second battery units are arranged under the floor panel and both sides in the vehicle width direction of the propeller shaft, it is possible to arrange the battery-related electrical component under the floor panel while securing the battery capacity and to protect the first and second battery units and the battery-related electrical component. 
       FIG.  1    is a schematic view of a vehicle body to which a vehicle lower structure according to the embodiment of the present disclosure is applied. A vehicle according to the embodiment of the present disclosure is a hybrid vehicle in a front-engine, rear-wheel-drive layout that has, as drive sources, an engine and a drive motor arranged in a vehicle front side and that transmits power from at least one of the engine and the drive motor to rear wheels as drive wheels arranged in a vehicle rear side. 
     As illustrated in  FIG.  1   , a vehicle body  1  of the hybrid vehicle has: an engine  3  as a drive source  2 ; an automatic transmission  4  as a transmission that is coupled to the engine  3 ; a motor (a drive motor)  5  as the drive source  2  that is arranged between the engine  3  and the automatic transmission  4 ; a propeller shaft  7  that is coupled to the automatic transmission  4  and transmits power from the drive source  2  to rear wheels  6 ; and a differential  8  that is coupled to the propeller shaft  7  and transmits the power from the drive source  2  to the right and left rear wheels  6 . 
     At a position under a floor panel  10  that constitutes a floor surface of a cabin  25 , the propeller shaft  7  extends in a vehicle longitudinal direction. A tunnel section  11  is provided in a center side in a vehicle width direction of the floor panel  10 . The propeller shaft  7  is arranged inside the tunnel section  11 . A front end portion of the propeller shaft  7  is coupled to the automatic transmission  4  via a universal joint  15 , and a rear end portion of the propeller shaft  7  is coupled to the differential  8  via a universal joint  16 . 
     In the vehicle body  1 , when an impact load is applied from a vehicle body front side to the drive source  2  during a frontal collision, the differential  8  receives the impact load through the propeller shaft  7 . When the differential  8  receives the impact load, the differential  8  is no longer supported by the vehicle body  1 , and a vehicle front side of the differential  8  rotates downward with an axle  9  being a fulcrum. When the vehicle front side of the differential  8  rotates downward, a vehicle rear side of the propeller shaft  7  moves downward and is deformed, and the drive source  2  moves rearward in the vehicle body  1 . In this way, an impact absorption property can be enhanced. 
     The vehicle body  1  includes an exhaust pipe  17  that extends in the vehicle longitudinal direction from the engine  3 . At a position under the tunnel section  11 , the exhaust pipe  17  is disposed under the propeller shaft  7 . A catalytic device  18  that includes a catalyst for purifying exhaust gas of the engine  3  is disposed as an exhaust system component on an upstream side of the exhaust pipe  17 . A silencer  19  that reduces noise generated at the time of releasing the exhaust gas of the engine  3  to the atmosphere is disposed as the exhaust system component on a downstream side of the exhaust pipe  17 . 
     The vehicle body  1  includes: a fuel tank  20  that stores fuel to be supplied to the engine  3 ; and a battery  30  that stores electricity to be supplied to the motor  5 . The motor  5  transmits the power to the rear wheels  6 . In addition, during deceleration of the vehicle, the motor  5  is rotationally driven by the propeller shaft  7  and performs regenerative power generation to supply the generated electricity to the battery  30 . 
     The battery  30  is formed as a battery pack  33  in which a first battery unit  31  and a second battery unit  32  are provided in an integrated manner. The first battery unit  31  and the second battery unit  32  are separately arranged from each other on both sides in the vehicle width direction of the propeller shaft  7 . Each of the first and second battery units  31 ,  32  is formed such that plural battery modules for storing the electricity to be supplied to the motor  5  are connected and unitized. The battery module includes plural battery cells, and each of the battery cells is a lithium-ion battery, for example. 
     The fuel tank  20  and the first and second battery units  31 ,  32  are arranged under the floor panel  10 . The fuel tank  20  is arranged on a vehicle rear side of the first and second battery units  31 ,  32  in a manner to be higher than the first and second battery units  31 ,  32 . 
     At positions near the first and second battery units  31 ,  32 , battery-related electrical components that are related to the battery  30  are arranged. As the battery-related electrical components, high-voltage components such as an inverter  41 , a DC/DC converter  42 , and a junction box  43  that are electrically connected to the first and second battery units  31 ,  32  are arranged. The high-voltage component and a high-voltage harness, which will be described below, respectively mean a component and a harness to which an AC voltage exceeding 30V or a DC voltage exceeding 60V is applied. 
     The inverter  41  converts DC power stored in the battery  30  into AC power and supplies the AC power to the motor  5 . In addition, during the deceleration of the vehicle, the inverter  41  converts the AC power generated by the motor  5  into the DC power and charges the battery  30  with the DC power. The DC/DC converter  42  converts high-voltage DC power, such as 300 volts, stored in the battery  30  into low-voltage DC power, such as 12 volts, and supplies the low-voltage DC power to an auxiliary machine and the like. 
     The junction box  43  includes: a front junction box  43   a  that is arranged on a vehicle front side of the first and second battery units  31 ,  32 ; and a rear junction box  43   b  that is arranged on a vehicle rear side of the first and second battery units  31 ,  32 . 
     Each of the front and rear junction boxes  43   a ,  43   b  is a so-called connection box for protecting terminals used for connecting, branching, and relaying harnesses, and has a high-voltage relay, a fuse, and the like. The front and rear junction boxes  43   a ,  43   b  are electrically connected to the first and second battery units  31 ,  32 . 
     The first and second battery units  31 ,  32  are electrically connected to each other by a battery harness as a high-voltage harness. The first and second battery units  31 ,  32  and the battery-related electrical components  41 ,  42 ,  43  are also electrically connected to each other by the battery harness as the high-voltage harness. The first and second battery units  31 ,  32  share the battery-related electrical components such as the junction box  43 . 
     At a position near the first and second battery units  31 ,  32 , a battery control unit  44  for controlling the first and second battery units  31 ,  32  is arranged. The battery control unit  44  is electrically connected to the first and second battery units  31 ,  32 , the battery-related electrical components  41 ,  42 ,  43 , and the like by harnesses. 
     Next, a specific description will be made on the vehicle lower structure according to the embodiment of the present disclosure with reference to  FIG.  2    to  FIG.  9   . 
       FIG.  2    is a top view of the vehicle body to which the vehicle lower structure according to the embodiment of the present disclosure is applied.  FIG.  3    is a bottom view of the vehicle body to which the vehicle lower structure according to the embodiment of the present disclosure is applied.  FIG.  4    is a cross-sectional view of the vehicle body that is taken along line Y 4 -Y 4  in  FIG.  2   .  FIG.  5    is a cross-sectional view of the vehicle body that is taken along line Y 5 -Y 5  in  FIG.  2   .  FIG.  6    is a cross-sectional view of the vehicle body that is taken along line Y 6 -Y 6  in  FIG.  2   .  FIG.  7    is a cross-sectional view of the vehicle body that is taken along line Y 7 -Y 7  in  FIG.  2   . 
     As illustrated in  FIG.  2   , the vehicle body  1  includes the floor panel  10 , right and left side sills  21 , a first crossmember  22 , and a second crossmember  23  in a lower portion of the vehicle body. The right and left side sills  21  are joined to both end portions in the vehicle width direction of the floor panel  10  and extend linearly in the vehicle longitudinal direction. On an upper surface side of the floor panel  10 , the first crossmember  22  and the second crossmember  23  are each hung between the right and left side sills  21  and extend in the vehicle width direction. 
     In the center side in the vehicle width direction, the floor panel  10  is formed with the tunnel section  11  that extends in the vehicle longitudinal direction and bulges upward. As illustrated in  FIG.  6   , the tunnel section  11  includes an upper surface portion  11   a  and side surface portions  11   b  on both sides, and is opened downward. As illustrated in  FIG.  5   , a front end portion of the floor panel  10  is coupled to a dashboard  24 . The dashboard  24  defines a vehicle front side of the cabin  25  and extends in a vehicle body vertical direction. 
     The floor panel  10  has a kick-up section  12  in a rear portion of the floor panel  10 . The kick-up section  12  is formed to be higher than a front portion of the floor panel  10 . The kick-up section  12  is provided under a rear seat  26 . The kick-up section  12  extends upward from the front portion of the floor panel  10  and then extends rearward in the vehicle in a substantially horizontal direction. 
     A rear floor panel  27  that is formed to be higher than a rear end portion of the kick-up section  12  is joined to a rear end portion of the floor panel  10 , more specifically, the rear end portion of the kick-up section  12 . The rear floor panel  27  extends upward from the rear end portion of the kick-up section  12  and then extends rearward in the vehicle in the substantially horizontal direction. 
     A third crossmember  28  is attached to a lower surface side of the rear floor panel  27 . The third crossmember  28  is hung between front end portions of right and left rear frames  14  and extends in the vehicle width direction. The third crossmember  28  is formed to have a substantially hat-shaped cross section and is joined to the rear floor panel  27 . 
     As illustrated in  FIG.  6   , in each of the right and left side sills  21 , a side sill inner  21   a  constitutes a vehicle body inner side of the side sill  21 , a side sill outer  21   b  constitutes a vehicle body outer portion of the side sill  21 , and the side sill inner  21   a  and the side sill outer  21   b  are joined to each other. In this way, each of the right and left side sills  21  has a closed cross-sectional shape. 
     The first and second crossmembers  22 ,  23  are separately arranged from each other in the vehicle longitudinal direction. The first crossmember  22  is arranged in front of the vehicle of the second crossmember  23 . Each of the first and second crossmembers  22 ,  23  is formed to have a substantially hat-shaped cross section and is joined to the floor panel  10 . 
     Each of the first and second crossmembers  22 ,  23  is divided in the vehicle width direction by the tunnel section  11 . In each of the divided first and second crossmembers  22 ,  23 , an outer end portion thereof in the vehicle width direction is joined to the side sill  21 , and an inner end portion thereof in the vehicle width direction is joined to the tunnel section  11 . 
     As illustrated in  FIG.  3   , right and left floor frames  50  are disposed on a lower surface side of the floor panel  10 . The right and left floor frames  50  separate from each other in the vehicle width direction and extend in the vehicle longitudinal direction. Each of the right and left floor frames  50  is arranged on an inner side in the vehicle width direction of the right and left side sills  21 , and is arranged between respective one of the side sills  21  and the tunnel section  11  in the vehicle width direction. 
     As illustrated in  FIG.  7   , the floor frame  50  includes a lower surface portion  50   a , side surface portions  50   b  on both sides, and flange portions  50   c  on both sides, and is formed to have a substantially hat-shaped cross section. The flange portions  50   c  on both sides are joined to the floor panel  10 . In this way, the floor frame  50  cooperates with the floor panel  10  to have a closed cross-sectional shape. 
     Front end portions of the right and left floor frames  50  are coupled to right and left front frames  13 , respectively. The right and left front frames  13  are disposed in the vehicle front side in a manner to separate from each other in the vehicle width direction, and extend substantially linearly in the vehicle longitudinal direction. Each of the right and left front frames  13  is formed to have a closed cross-sectional shape and extends forward in the vehicle from the dashboard  24 . 
     Rear end portions of the right and left floor frames  50  are coupled to the right and left rear frames  14 , respectively. The right and left rear frames  14  are disposed in the vehicle rear side in a manner to separate from each other in the vehicle width direction, and extend substantially linearly in the vehicle longitudinal direction. Each of the right and left rear frames  14  is formed to have a substantially hat-shaped cross section, is attached to the lower surface side of the rear floor panel  27 , and cooperates with the rear floor panel  27  to have a closed cross-sectional shape. 
     Each of the right and left floor frames  50  has a front inclined section  51 , a width increased section  52 , and a rear inclined section  53 . The front inclined section  51  is inclined to the outer side in the vehicle width direction from the vehicle front side toward the vehicle rear side. The width increased section  52  extends linearly and rearward in the vehicle from the front inclined section  51 , and a width thereof is increased to the outer side in the vehicle width direction. The rear inclined section  53  is inclined to the inner side in the vehicle width direction from the width increased section  52  toward the vehicle rear side. Each of the right and left floor frames  50  is formed such that a width in a center side in the vehicle longitudinal direction is increased to the outer side in the vehicle width direction in comparison with a vehicle front side and a vehicle rear side and that a distance between the right and left width increased sections  52  in the vehicle width direction is longer than that between the front inclined sections  51  and that between the rear inclined sections  53 . 
     As illustrated in  FIG.  6   , right and left tunnel reinforcing members  54  are joined to the lower surface side of the floor panel  10 . The right and left tunnel reinforcing members  54  are disposed on both sides in the vehicle width direction of the tunnel section  11  in a manner to separate from each other in the vehicle width direction and extend in the vehicle longitudinal direction. The tunnel reinforcing member  54  is joined to the lower surface side of the floor panel  10  and cooperates with the floor panel  10  to have a closed cross-sectional shape. 
     As illustrated in  FIG.  2   , right and left floor reinforcing members  56  are joined to the upper surface side of the floor panel  10 . The right and left floor reinforcing members  56  each extend in the vehicle longitudinal direction along the front inclined section  51  of the floor frame  50 . The floor reinforcing member  56  cooperates with the floor panel  10  to have a closed cross-sectional shape. A front end portion of the floor reinforcing member  56  is joined to the dashboard  24 , and a rear end portion of the floor reinforcing member  56  is joined to the first crossmember  22 . Vehicle body components such as the floor panel  10 , the floor frame  50 , and the tunnel reinforcing member  54  are each formed by pressing a steel sheet, for example. 
     At the positions under the floor panel  10 , the automatic transmission  4  and the propeller shaft  7  are arranged in the center side in the vehicle width direction. As illustrated in  FIG.  4   , the automatic transmission  4  and the propeller shaft  7  are arranged in the tunnel section  11  and are supported by the vehicle body  1 . As illustrated in  FIG.  3   , the automatic transmission  4  is arranged between the front inclined sections  51  of the right and left floor frames  50 , and the propeller shaft  7  is arranged between the width increased sections  52  and between the rear inclined sections  53  of the right and left floor frames  50 . 
     At a position under the floor panel  10 , the fuel tank  20  is disposed between the rear inclined sections  53  of the right and left floor frames  50 . The fuel tank  20  is arranged under the kick-up section  12  of the floor panel  10  and is arranged to be higher than the front portion of the floor panel  10 . 
     As illustrated in  FIG.  5   , an upper surface portion  20   a  of the fuel tank  20  is arranged to be higher than the front portion of the floor panel  10 , and a lower surface portion  20   b  of the fuel tank  20  is arranged to be lower than the front portion of the floor panel  10 . The fuel tank  20  is formed to extend between both sides in the vehicle width direction and extend in the vehicle longitudinal direction. The fuel tank  20  is formed with a hollow space that stores the fuel therein. 
     As illustrated in  FIG.  4   , the fuel tank  20  has a concave section  20   c  at a center in the vehicle width direction of the lower surface portion  20   b . The concave section  20   c  is dented upward in a substantially semicircular cross-sectional shape so as to avoid interference with the propeller shaft  7 . As illustrated in  FIG.  3   , the fuel tank  20  is supported from below by right and left fixture belts  57  for fixing the fuel tank  20 , and is thereby fixed to the vehicle body  1 . A front end portion of the fixture belt  57  is fixed by a fastening bolt to a tank attachment member  58  that is attached to the width increased section  52  of the floor frame  50 . A rear end portion of the fixture belt  57  is fixed by a fastening bolt to a tank attachment member  59  that is attached to a center side in the vehicle width direction of the third crossmember  28 . 
     The exhaust pipe  17 , which extends from the engine  3 , and the catalytic device  18  are arranged under the floor panel  10 . The exhaust pipe  17  and the catalytic device  18  are supported by the floor panel  10 . The catalytic device  18  is disposed between the front inclined sections  51  of the right and left floor frames  50 , and is arranged between the automatic transmission  4  and the front inclined section  51  of the floor frame  50  on the vehicle right side as one side in the vehicle width direction. 
     In the exhaust pipe  17  arranged under the floor panel  10 , a portion on an upstream side of the catalytic device  18  extends forward in the vehicle along the front inclined section  51  of the floor frame  50  and is coupled to the engine  3 , and a portion on a downstream side of the catalytic device  18  extends inward in the vehicle width direction, then extends substantially linearly to the rear in the vehicle, and is coupled to the silencer  19 . 
     At the position under the tunnel section  11  of the floor panel  10 , the exhaust pipe  17  extends in the vehicle longitudinal direction under the propeller shaft  7 . As illustrated in  FIG.  6   , at the position under the tunnel section  11  of the floor panel  10 , the exhaust pipe  17  is disposed at such a position that a center axis  7   a  of the propeller shaft  7  matches a center axis  17   a  of the exhaust pipe  17  in the vehicle width direction. 
     At positions under the floor panel  10 , the first and second battery units  31 ,  32  are disposed in a manner to be separately arranged from each other on both sides in the vehicle width direction of the propeller shaft  7 . Each of the first and second battery units  31 ,  32  is formed as a high-voltage battery in which the plural battery modules are connected and unitized. 
     At positions in front of the vehicle of the kick-up section  12  of the floor panel  10 , the first and second battery units  31 ,  32  are arranged between the width increased sections  52  of the right and left floor frames  50 . The first battery unit  31  is arranged between the propeller shaft  7  and the width increased section  52  of the floor frame  50  on the vehicle left side in the vehicle width direction, and the second battery unit  32  is arranged between the propeller shaft  7  and the width increased section  52  of the floor frame  50  on the vehicle right side in the vehicle width direction. The first and second battery units  31 ,  32  are integrally formed as the battery pack  33  and are supported by the vehicle body  1 . 
       FIG.  8    is a perspective view of the battery pack  33 , and  FIG.  9    is a cross-sectional view of the battery pack  33  that is taken along line Y 9 -Y 9  in  FIG.  8   . As illustrated in  FIG.  8    and  FIG.  9   , the battery pack  33  has: the first and second battery units  31 ,  32  that are arranged separately from each other on both sides in the vehicle width direction of the propeller shaft  7 ; and a battery cover  60  that accommodates the first and second battery units  31 ,  32 . 
     Each of the first and second battery units  31 ,  32  is formed to have a substantially rectangular shape in a plan view, and is formed in a substantially rectangular parallelepiped shape. Although the first and second battery units  31 ,  32  are not limited thereto, the first and second battery units  31 ,  32  are formed to be substantially symmetrical on the both sides in the vehicle width direction of the propeller shaft  7 . As described above, the first and second battery units  31 ,  32  are arranged between the width increased sections  52  of the floor frames  50 , and are each formed to have large battery capacity by increasing a width thereof in the vehicle width direction in comparison with a case where the width of the floor frame is not increased to the outer side in the vehicle width direction. 
     The battery cover  60  has: a first battery accommodation section  61  that accommodates the first battery unit  31 ; a second battery accommodation section  66  that accommodates the second battery unit  32 ; and a coupling section  71  that couples the first battery accommodation section  61  and the second battery accommodation section  66  and extends in the vehicle width direction. The battery cover  60  is formed of an aluminum material, for example. 
     The first battery accommodation section  61  is formed in a substantially rectangular parallelepiped shape, and is configured to include: a first upper cover member  62  that constitutes an upper portion of the first battery accommodation section  61 ; and a first lower cover member  63  that constitutes a lower portion of the first battery accommodation section  61 . 
     The first upper cover member  62  includes: an upper surface section  62   a  that is formed in a substantially rectangular shape and extends in a substantially horizontal direction; a side surface section  62   b  that extends downward from a peripheral edge portion of the upper surface section  62   a ; and a flange section  62   c  that extends outward in the substantially horizontal direction from a lower end portion of the side surface section  62   b , and is formed such that the upper surface section  62   a  bulges upward. 
     The first lower cover member  63  includes: a lower surface section  63   a  that is formed in a substantially rectangular shape and extends in the substantially horizontal direction; a side surface section  63   b  that extends upward from a peripheral edge portion of the lower surface section  63   a ; and a flange section  63   c  that extends outward in the substantially horizontal direction from an upper end portion of the side surface section  63   b , and is formed such that the lower surface section  63   a  bulges downward. 
     The first battery accommodation section  61  is formed by joining the flange section  62   c  and the flange section  63   c  so as to join the first upper cover member  62  and the first lower cover member  63 . The first battery unit  31  is attached to the lower surface section  63   a  of the first lower cover member  63  and is accommodated in a space defined by the first upper cover member  62  and the first lower cover member  63 . 
     In a vehicle front side of the first battery accommodation section  61 , the first battery accommodation section  61  is formed with a front extending section  64  that extends forward in the vehicle in a substantially rectangular parallelepiped shape from an outer side in the vehicle width direction. Each of the first upper cover member  62  and the first lower cover member  63  extends forward in the vehicle from the outer side in the vehicle width direction of the vehicle front side, so as to form the front extending section  64 . 
     The front junction box  43   a  is formed in a substantially rectangular parallelepiped shape and is also formed in a flat shape. The front junction box  43   a  is transversely arranged such that a height thereof in the vertical direction is shorter than a length thereof in the vehicle longitudinal direction. On the vehicle front side of the first battery unit  31 , the front junction box  43   a  is attached to the lower surface section  63   a  of the first lower cover member  63  that constitutes the front extending section  64 , and is accommodated in the space defined by the first upper cover member  62  and the first lower cover member  63 . 
     As illustrated in  FIG.  3   , in the first battery accommodation section  61 , the upper surface section  62   a  of the first upper cover member  62  is formed with a first opening  62   d  at a position on the vehicle rear side of the first battery unit  31 . The first opening  62   d  is formed in a substantially rectangular shape, and is also formed in a long hole shape that is longer in the vehicle width direction than in the vehicle longitudinal direction. The rear junction box  43   b , the battery harness, and the like are inserted through the first opening  62   d.    
     The second battery accommodation section  66  is formed in a substantially rectangular parallelepiped shape, and is configured to include: a second upper cover member  67  that constitutes an upper portion of the second battery accommodation section  66 ; and a second lower cover member  68  that constitutes a lower portion of the second battery accommodation section  66 . 
     The second upper cover member  67  includes: an upper surface section  67   a  that is formed in a substantially rectangular shape and extends in the substantially horizontal direction; a side surface section  67   b  that extends downward from a peripheral edge portion of the upper surface section  67   a ; and a flange section  67   c  that extends outward in the substantially horizontal direction from a lower end portion of the side surface section  67   b . The second upper cover member  67  is formed such that the upper surface section  67   a  bulges upward. 
     The second lower cover member  68  includes: a lower surface section  68   a  that is formed in a substantially rectangular shape and extends in the substantially horizontal direction; a side surface section  68   b  that extends upward from a peripheral edge portion of the lower surface section  68   a ; and a flange section  68   c  that extends outward from an upper end portion of the side surface section  68   b  in the substantially horizontal direction. The second lower cover member  68  is formed such that the lower surface section  68   a  bulges downward. 
     The second battery accommodation section  66  is formed by joining the flange section  67   c  and the flange section  68   c  so as to join the second upper cover member  67  and the second lower cover member  68 . The second battery unit  32  is attached to the lower surface section  68   a  of the second lower cover member  68  and is accommodated in a space defined by the second upper cover member  67  and the second lower cover member  68 . 
     As illustrated in  FIG.  3   , in the second battery accommodation section  66 , the upper surface section  67   a  of the second upper cover member  67  is formed with a second opening  67   d  at a position on the vehicle rear side of the second battery unit  32 . The second opening  67   d  is formed in a substantially rectangular shape, and is also formed in a long hole shape that is longer in the vehicle width direction than in the vehicle longitudinal direction. The battery control unit  44 , the battery harness, and the like are inserted through the second opening  67   d.    
     The coupling section  71  is formed in a substantially rectangular parallelepiped shape that extends longer in the vehicle width direction than in the vehicle longitudinal direction and the vertical direction. The coupling section  71  couples vehicle rear sides of the first battery accommodation section  61  and the second battery accommodation section  66 . The coupling section  71  is formed such that a length thereof in the vehicle longitudinal direction is less than that of each of the first and second battery accommodation sections  61 ,  66 . 
     The coupling section  71  is higher than the first and second battery accommodation sections  61 ,  66 , couples the first and second battery accommodation sections  61 ,  66 , extends in the vehicle width direction, and is arranged next to a vehicle front side of the fuel tank  20 . As illustrated in  FIG.  9   , the coupling section  71  is configured to include: a front cover member  72  that constitutes a vehicle front side of the coupling section  71 ; and a rear cover member  73  that constitutes a vehicle rear side of the coupling section  71 . 
     The front cover member  72  includes: a lower surface section  72   a  that is attached to the upper surface sections  62   a ,  67   a  of the first and second battery accommodation sections  61 ,  66 ; and a peripheral wall section  72   b  that extends upward from the lower surface section  72   a . As illustrated in  FIG.  3   , in the lower surface section  72   a  of the front cover member  72 , a first opening  72   c  and a second opening  72   d  are formed on both sides in the vehicle width direction. The first opening  72   c  and the second opening  72   d  respectively correspond to the first opening  62   d  of the first battery accommodation section  61  and the second opening  67   d  of the second battery accommodation section  66 . 
     The first and second openings  72   c ,  72   d  of the front cover member  72  are formed in the substantially same shapes as the first and second openings  62   d ,  67   d  of the first and second battery accommodation sections  61 ,  66 . Each of the first and second openings  72   c ,  72   d  of the front cover member  72  is formed in a substantially rectangular shape, and is also formed in a long hole shape that is longer in the vehicle width direction than in the vehicle longitudinal direction. The rear junction box  43   b , the battery harness, and the like are inserted through the first opening  72   c . The battery control unit  44 , the battery harness, and the like are inserted through the second opening  72   d.    
     The peripheral wall section  72   b  of the front cover member  72  extends upward from the lower surface section  72   a  and constitutes the vehicle front side and both sides in the vehicle width direction of the coupling section  71 . A vehicle rear side of the peripheral wall section  72   b  is formed with a mating surface  72   e  with the rear cover member  73 . The entire mating surface  72   e  in the vehicle width direction of the front cover member  72  is formed to be inclined downward toward the vehicle rear side. 
     The rear cover member  73  includes: an upper surface section  73   a ; and a peripheral wall section  73   b  that extends downward from the upper surface section  73   a . The peripheral wall section  73   b  of the rear cover member  73  extends downward from the upper surface section  73   a  and constitutes the vehicle rear side and both sides in the vehicle width direction of the coupling section  71 . A vehicle front side of the peripheral wall section  73   b  is formed with a mating surface  73   c  with the front cover member  72 . The entire mating surface  73   c  in the vehicle width direction of the rear cover member  73  is formed to be inclined downward toward the vehicle rear side. 
     In the front cover member  72 , the lower surface section  72   a  is superposed on the upper surface sections  62   a ,  67   a  of the first and second battery accommodation sections  61 , and is joined to the first and second battery accommodation sections  61 ,  66  by using plural fastening bolts B, each of which extends in the vertical direction. The rear cover member  73  is joined to the front cover member  72  using plural fastening bolts B, each of which is inclined and extends forward and downward in the vehicle, by causing the mating surface  73   c  of the rear cover member  73  to mate with the mating surface  72   e  of the front cover member  72 . 
     The coupling section  71  is formed with a hollow space therein by joining the front cover member  72  and the rear cover member  73  to each other. The coupling section  71  has a concave section  76   a  in a lower portion of a center section  76  in the vehicle width direction, and the concave section  76   a  is dented upward. The concave section  76   a  of the coupling section  71  is formed between the first battery accommodation section  61  and the second battery accommodation section  66  in a manner to correspond to the tunnel section  11  of the floor panel  10 . 
     In the coupling section  71 , the center section  76  in the vehicle width direction is formed such that a length thereof in the vertical direction is reduced by the concave section  76   a  to be shorter than that of an outer section  77  in the vehicle width direction on each side of the center section  76 . The center section  76  in the vehicle width direction of the coupling section  71  functions as a fragile section  76  that is fragile with respect to the impact load applied from the outer side in the vehicle width direction when the impact load is applied to the battery pack  33  from the outer side in the vehicle width direction. 
     The rear junction box  43   b  is arranged in the outer section  77  in the vehicle width direction on the vehicle left side of the coupling section  71 . The rear junction box  43   b  is formed in a flat shape and is vertically arranged such that a length thereof in the vehicle longitudinal direction is less than a height thereof in the vertical direction. 
     As illustrated in  FIG.  9   , the rear junction box  43   b  is attached onto a base  63   d  that is provided in the first battery accommodation section  61 , and is accommodated in the coupling section  71  and the first battery accommodation section  61  through the first opening  62   d  of the first battery accommodation section  61  and the first opening  72   c  of the coupling section  71 . The rear junction box  43   b  is arranged next to the vehicle front side of the fuel tank  20  such that a height thereof is greater than that of each of the first and second battery units  31 ,  32 . 
     The battery control unit  44  is arranged in the outer section  77  in the vehicle width direction on the vehicle right side of the coupling section  71 . The battery control unit  44  is formed in a flat shape and is vertically arranged such that a length thereof in the vehicle longitudinal direction is less than a height thereof in the vertical direction. 
     Similar to the rear junction box  43   b , the battery control unit  44  is attached onto a base that is provided in the second battery accommodation section  66 , and is accommodated in the coupling section  71  and the second battery accommodation section  66  through the second opening  67   d  of the second battery accommodation section  66  and the second opening  72   d  of the coupling section  71 . The battery control unit  44  is arranged next to the vehicle front side of the fuel tank  20  such that a height thereof is greater than that of each of the first and second battery units  31 ,  32 . 
     As illustrated in  FIG.  8   , in the coupling section  71 , the battery harnesses such as a battery harness  78  and a battery harness  79  extend in the vehicle width direction through the center section  76  in the vehicle width direction. The battery harness  78  electrically connects the first and second battery units  31 ,  32 . The battery harness  79  electrically connects the rear junction box  43   b  and the battery control unit  44 . 
     As illustrated in  FIG.  6   , in regard to the battery pack  33 , plural attachment sections  61   a ,  66   a  on the outer sides in the vehicle width direction of the first and second battery accommodation sections  61 ,  66  are fixed to the floor frame  50  by using plural fastening bolts B, plural attachment sections  61   b ,  66   b  on the inner sides in the vehicle width direction of the first and second battery accommodation sections  61 ,  66  are fixed to the tunnel reinforcing member  54  by using plural fastening bolts B. In this way, at a position next to the vehicle front side of the fuel tank  20 , the battery pack  33  is attached to a lower portion of the floor panel  10 . 
     When the battery pack  33  is attached to the lower portion of the floor panel  10 , the first and second battery units  31 ,  32  are separately arranged from each other on both sides in the vehicle width direction of the propeller shaft  7 , the coupling section  71  is arranged under the kick-up section  12  of the floor panel  10  and above the propeller shaft  7 , and the battery harness  78 , which electrically connects the first and second battery units  31 ,  32 , is disposed in a manner to run above the propeller shaft  7 . 
     In addition, the coupling section  71  of the battery pack  33  is arranged to be higher than the first and second battery accommodation sections  61 ,  66 , and, at the position under the kick-up section  12  of the floor panel  10  arranged under the rear seat  26 , is arranged in front of the vehicle of the fuel tank  20 . 
     The rear junction box  43   b  and the battery control unit  4  are arranged under the kick-up section  12  of the floor panel  10 , and are separately arranged from each other on both sides in the vehicle width direction of the propeller shaft  7 . The battery control unit  44  is arranged at such a position that the battery control unit  44  overlaps at least a part of the rear junction box  43   b  in the vehicle longitudinal direction in a vehicle side view. 
     As illustrated in  FIG.  5   , the inverter  41  and the DC/DC converter  42  as the battery-related electrical components are arranged in the battery pack  33 , more specifically, at positions near the vehicle front side of the first battery accommodation section  61 . Each of the inverter  41  and the DC/DC converter  42  is formed in a flat shape, and is transversely arranged such that a height thereof in the vertical direction is less than a length thereof in the vehicle longitudinal direction. As illustrated in  FIG.  3   , each of the inverter  41  and the DC/DC converter  42  is formed in a substantially rectangular shape in the plan view. 
     Each of the inverter  41  and the DC/DC converter  42  is formed to have a width in the vehicle width direction that is less than that of each of the first and second battery units  31 ,  32 . The DC/DC converter  42  is formed such that the width thereof in the vehicle width direction is less than that of the inverter  41  and the length thereof in the vehicle longitudinal direction is greater than that of the inverter  41 . 
     The inverter  41  and the DC/DC converter  42  are arranged between the front inclined sections  51  of the right and left floor frames  50 , and are arranged between the transmission  4  and the front inclined section  51  of the floor frame  50  on the vehicle left side. The inverter  41  and the DC/DC converter  42  are arranged such that inner sides thereof in the vehicle width direction substantially match each other in the vehicle width direction. 
     The DC/DC converter  42  is arranged in front of the vehicle of the inverter  41 , and is arranged on an upper side of the inverter  41  in a superposing manner in the vertical direction. As illustrated in  FIG.  5    and  FIG.  7   , in a state of being accommodated in an inverter case  41   a  and a converter case  42   a , the inverter  41  and the DC/DC converter  42  are directly or indirectly attached to the floor panel  10  by using plural fastening bolts B. 
     The inverter  41  and the DC/DC converter  42  are arranged between the transmission  4  and the floor frame  50  on the vehicle body left side, and the catalytic device  18  is arranged between the transmission  4  and the floor frame  50  on the vehicle body right side. The catalytic device  18  and a combination of the inverter  41  and the DC/DC converter  42  are separately arranged from each other on one side and the other side in the vehicle width direction. In the vehicle side view, the inverter  41  and the DC/DC converter  42  are arranged at positions that overlap at least a part of the catalytic device  18  in the vehicle longitudinal direction. 
     The inverter  41  and the DC/DC converter  42  are electrically connected to the first battery unit  31  and the front junction box  43   a  by a battery harness  80  as the high-voltage harness. On the inner side in the vehicle width direction of the front extending section  64  of the first battery accommodation section  61 , the battery harness  80 , which electrically connects the combination of the inverter  41  and the DC/DC converter  42  to a combination of the first battery unit  31  and the front junction box  43   a , extends in the vehicle longitudinal direction along the front extending section  64 . 
     Although not illustrated, the vehicle body  1  also includes a battery-related electrical component such as a heater unit at a position between the transmission  4  and the front inclined section  51  of the floor frame  50  on the vehicle left side. The heater unit warms the cabin  25 . The heater unit is formed in a flat shape, and is configured by a sheet like electric wire heater, a positive temperature coefficient (PTC) heater, for example. 
     In the vehicle body  1  that is configured as described above, in the case where the impact load is applied thereto from the front side of the vehicle body  1  during the frontal collision, and the impact load is applied to the drive source  2  from the front side of the vehicle body  1 , the vehicle front side of the differential  8  rotates downward, the vehicle rear side of the propeller shaft  7  moves downward and is deformed, and the drive source  2  moves rearward in the vehicle body  1 . 
     At the positions under the floor panel  10 , the first and second battery units  31 ,  32  are arranged on both sides in the vehicle width direction of the propeller shaft  7 . Thus, even in the case where the vehicle rear side of the propeller shaft  7  moves downward and is deformed, it can be possible to suppress the propeller shaft  7  from coming into contact with the first and second battery units  31 ,  32 . The battery harness  78 , which electrically connects the first and second battery units  31 ,  32 , is arranged to run above the propeller shaft  7 . Thus, it also can be possible to suppress the propeller shaft  7  from coming into contact with the battery harness  78 . 
     In addition, the vehicle body  1  includes the fragile section  76  in the coupling section  71  of the battery pack  33 . Accordingly, in the case where the impact load is applied to the vehicle body  1  from the outer side in the vehicle width direction during a lateral collision, and the impact load is applied to the battery pack  33  from the outer side in the vehicle width direction, the fragile section  76  can be crushed and deformed. Thus, it can be possible to suppress the first and second battery accommodation sections  61 ,  66  from being crushed and deformed. 
     As described above, the vehicle lower structure according to this embodiment includes, at the position under the floor panel  10 : the first and second battery units  31 ,  32  that are arranged on both sides in the vehicle width direction of the propeller shaft  7 ; and the right and left floor frames  50  disposed on the lower surface side of the floor panel  10 . Each of the right and left floor frames  50  has: the front inclined section  51 ; and the width increased section  52  that extends linearly to the rear in the vehicle from the front inclined section  51 . The first and second battery units  31 ,  32  are arranged between the width increased sections  52  of the right and left floor frames  50 . The battery-related electrical components  41 ,  42 , the width of each of which in the vehicle width direction is less than the width of each of the first and second battery units  31 ,  32 , are arranged between the front inclined sections  51 . 
     Since the first and second battery units  31 ,  32  are arranged at the positions under the floor panel  10  between the width increased sections  52  of the right and left floor frames  50 , compared to the case where the widths of the floor frames are not increased to the outer side in the vehicle width direction, it is possible to enlarge the first and second battery units  31 ,  32  in the vehicle width direction so as to secure the battery capacity of each of the first and second battery units  31 ,  32 . In addition, the first and second battery units  31 ,  32  can be protected by the right and left floor frames  50  during the lateral collision. 
     At the positions under the floor panel  10 , the battery-related electrical components  41 ,  42 , the width of each of which in the vehicle width direction is less than that of each of the first and second battery units  31 ,  32 , are arranged between the front inclined sections  51  of the right and left floor frames  50 . Thus, it is possible to arrange the battery-related electrical components  41 ,  42  in a space that is near the first and second battery units  31 ,  32 , between the front inclined sections  51  that are inclined outward in the vehicle width direction, and is smaller than a space between the width increased sections  52  of the right and left floor frames  50 . In addition, the battery-related electrical components  41 ,  42  can be protected by the right and left floor frames  50  during the lateral collision. 
     Thus, in the vehicle in which, at the positions under the floor panel  10 , the first and second battery units  31 ,  32  are arranged on both sides in the vehicle width direction of the propeller shaft  7 , it is possible to arrange the battery-related electrical components  41 ,  42  under the floor panel  10  while securing the battery capacity and to protect the first and second battery units  31 ,  32  and the battery-related electrical components  41 ,  42 . 
     The battery-related electrical components  41 ,  42  are the DC/DC converter  42  and the inverter  41 . The DC/DC converter  42  is formed such that the width thereof in the vehicle width direction is less than that of the inverter  41 , and is arranged in front of the vehicle of the inverter  41 . Accordingly, it is possible to sequentially arrange the DC/DC converter  42  and the inverter  41  from the vehicle front side along the front inclined section  51  at the positions between the front inclined sections  51  of the floor frames  50 . Therefore, it is possible to effectively use the space between the front inclined sections  51  of the floor frames  50 . 
     The DC/DC converter  42  is formed such that the length thereof in the vehicle longitudinal direction is greater than that of the inverter  41 , and is arranged to be superposed on the inverter  41  in the vertical direction. Accordingly, it is possible to arrange the DC/DC converter  42  and the inverter  41  to be compact in the vehicle longitudinal direction by effectively using the space between the front inclined sections  51  of the floor frames  50 . 
     The transmission  4 , which is coupled to the engine  3 , is coupled to the vehicle front side of the propeller shaft  7 , and the battery-related electrical components  41 ,  42  are arranged between the transmission  4  and one of the right and left floor frames  50 . In this way, in the case where the transmission  4 , the width of which in the vehicle width direction is greater than that of the propeller shaft  7 , is arranged between the front inclined sections  51  of the right and left floor frames  50 , it is possible to arrange the battery-related electrical components  41 ,  42  to be compact by effectively using the space between the transmission  4  and one of the front inclined sections  51  of the floor frames  50 . 
     At the position between the front inclined sections  51  of the right and left floor frames  50 , the exhaust system component  18  of the engine  3  is arranged between the transmission  4  and the other of the right and left floor frames  50 . In this way, it is possible to arrange the exhaust system component  18  of the engine  3  by effectively using the space between the transmission  4  and the other of the front inclined sections  51  of the floor frames  50 . 
     Each of the right and left floor frames  50  has the rear inclined section  53  that is inclined to the inner side in the vehicle width direction from the width increased section  52  toward the vehicle rear side. The fuel tank  20  is arranged between the rear inclined sections  53  of the right and left floor frames  50 . Accordingly, it is possible to arrange the fuel tank  20  by using the space between the rear inclined sections  53  of the floor frames  50  and to protect the fuel tank  20  by the right and left floor frames  50  during the lateral collision. 
     In this embodiment, the drive motor  5  is arranged between the engine  3  and the transmission  4 . However, the drive motor may be arranged separately from the engine  3  and the transmission  4 , and the power from at least one of the engine  3  and the drive motor  5  may be transmitted to the drive wheels  6 . 
     The vehicle according to this embodiment is the hybrid vehicle of an engine vertically arranged type in which the engine  3  is arranged in the vehicle front side and the power from the engine  3  is transmitted to the drive wheels  6  arranged in the vehicle rear side. However, embodiments of the present disclosure can also be applied to a four-wheel-drive hybrid vehicle of the engine vertically arranged type. 
     Embodiments of the present disclosure are not limited to the exemplary embodiment, and various improvements and design changes can be made thereto within the scope that does not depart from the gist of the present disclosure. 
     INDUSTRIAL APPLICABILITY 
     As it has been described so far, according to one or more embodiments of the present disclosure, in the vehicle in which, at the positions under the floor panel, the first and second battery units are arranged on both sides in the vehicle width direction of the propeller shaft, it is possible to arrange the battery-related electrical component under the floor panel while securing the battery capacity and to protect the first and second battery units and the battery-related electrical component. Therefore, one or more embodiments of the disclosed subject matter can be possibly and favorably used in this type of the vehicle.