Vehicle underbody structure

1. A vehicle underbody structure, comprising:

a pair of rockers that are provided at both vehicle width direction sides of a vehicle underbody and extend in a vehicle front-rear direction;

a battery that is disposed centrally in a vehicle width direction between the pair of rockers, is disposed above a vehicle floor and at a lower side of a seat, and is in a recess portion in an upper surface of a floor panel;

a fuel tank that is disposed centrally in the vehicle width direction between the pair of rockers, and is disposed under the vehicle floor and further toward a rear side of the vehicle than the battery;

a waste pipe that is coupled to a drive unit provided at a vehicle front side of the battery and extends in the vehicle front-rear direction between the battery and one of the rockers, wherein the drive unit includes an inverter, the inverter is outside of the recess portion, and the inverter is forward of the battery in the vehicle front-rear direction;

a high-voltage cable coupling the inverter and the battery;

a pair of first frame members that are respectively disposed between one or another of the pair of rockers and the battery and extend in the vehicle front-rear direction; and

second frame members that couple the first frame members to each other in the vehicle width direction and are respectively disposed at least between the battery and the drive unit and between the battery and the fuel tank as seen in a vehicle plan view.

2. The vehicle underbody structure according to claim 1 , wherein the battery and the fuel tank are disposed at positions that overlap with the rockers as seen in a vehicle side view.

3. The vehicle underbody structure according to claim 1 , wherein the battery is disposed at a lower side of at least one of a driver's seat or a front passenger seat.

4. The vehicle underbody structure according to claim 1 , wherein:

the second frame members are disposed at the vehicle front side and the vehicle rear side of the fuel tank, and

the fuel tank is surrounded on four sides by the pair of first frame members and the second frame members, as seen in a plan view.

5. The vehicle underbody structure according to claim 1 , wherein:

a pair of front side members that extend in the vehicle front-rear direction are provided at front end portions of the pair of first frame members,

a pair of rear side members that extend in the vehicle front-rear direction are provided at rear end portions of the pair of first frame members, and

each of the pair of first frame members is offset outward in the vehicle width direction from the front side members and the rear side members, as seen in a plan view.

6. The vehicle underbody structure according to claim 1 , wherein the waste pipe is disposed further inward in the vehicle width direction than the first frame members.

7. The vehicle underbody structure according to claim 1 , wherein:

the waste pipe is disposed at a vehicle lower side of the floor panel.

8. The vehicle underbody structure according to claim 1 , wherein:

the fuel tank is a gasoline tank,

the drive unit is configured to include a gasoline engine, and

the waste pipe is an exhaust gas pipe that discharges, to outside of the vehicle, exhaust gas from the gasoline engine.

9. The vehicle underbody structure according to claim 1 , wherein:

the fuel tank is a hydrogen tank,

the drive unit is configured to include a fuel cell stack, and

the waste pipe is a water discharge pipe that discharges, to outside of the vehicle, waste water from the fuel cell stack.