Electric vehicle battery case to floor attachment structure

1 . A battery case comprising:

a floor panel of a vehicle, which forms a floor of a body of the vehicle and an upper panel of a battery case;

a side sill positioned at opposite sides of the floor panel, extending in a longitudinal direction of the vehicle, and extending downwardly from the floor panel in a height direction of the vehicle; and

front and rear barriers extending downwardly from a front portion and a rear portion of the floor panel connected to the side sill to form a sidewall portion of the battery case together with the side sill by being connected to the side sill,

wherein an upper cross member is formed on a top surface of the floor panel to extend in a width direction of the vehicle and protrude upwardly, and

wherein a rear cross member extending upwardly is formed in the rear portion of the floor panel, and a plurality of rear upper side members extending in the longitudinal direction of the vehicle to connect the rear cross member to the upper cross member are formed on a top surface of the floor panel, wherein the plurality of rear upper side members are spaced apart from each other.

2 . The battery case of claim 1 , wherein the floor panel and the upper cross member are molded integrally through an extrusion method.

3 . The battery case of claim 2 , wherein each of the floor panel and the upper cross member is molded to include a closed cross section.

4 . The battery case of claim 1 , wherein a lower cross member is configured in plural and the lower cross member is formed on a bottom surface of the floor panel to extend in a width direction of the vehicle and protrude downwardly.

5 . The battery case of claim 4 , wherein lower cross members are formed spaced from each other, and a battery module is positioned in a space where the lower cross members are formed spaced from each other.

6 . The battery case of claim 4 , wherein the floor panel and the lower cross member are molded integrally through an extrusion method.

7 . The battery case of claim 1 , wherein a lower center member formed in the longitudinal direction of the vehicle and positioned in a center portion of a bottom surface of the floor panel is formed on the bottom surface of the floor panel, and battery modules are disposed with the lower center member therebetween.

8 . The battery case of claim 1 , wherein a dash cross member extending upwardly is formed in the front portion of the floor panel, and a front upper side member extending in the longitudinal direction of the vehicle to connect the dash cross member to the upper cross member is formed on a top surface of the floor panel.

9 . The battery case of claim 1 , wherein an internal protrusion is formed in a direction inwardly from the vehicle in the side sill, the internal protrusion is positioned under the floor panel, and the side sill and the internal protrusion are formed using an extrusion molding method to form a closed cross section.

10 . The battery case of claim 9 , wherein the internal protrusion of the side sill surface-contacts with a lower cross member formed in a width direction of the vehicle on a bottom surface of the floor panel.

11 . The battery case of claim 9 , further including a battery lower case,

wherein the battery lower case is coupled to the floor panel having a battery module mounted thereon, and in coupling of the battery lower case, an upper end portion of the internal protrusion of the side sill surface-contacts with the bottom surface of the floor panel and a lower end portion of the internal protrusion surface-contacts with the battery lower case.

12 . The battery case of claim 9 , wherein an external protrusion is formed in a direction outwardly from the vehicle in the side sill, and the external protrusion extends in the longitudinal direction of the vehicle, and an upper end portion thereof is positioned at a same height as or higher than the floor panel.

13 . The battery case of claim 1 , wherein front and rear barriers are formed to include a closed cross section in a width direction of the vehicle, and opposite end portions of the front and rear barriers are bent in a direction of a wheel housing of the vehicle.

14 . The battery case of claim 13 , wherein the front and rear barriers are formed by mechanical coupling between a center portion formed in the width direction of the vehicle and a bent portion formed to be bent in the direction of the wheel housing of the vehicle.

15 . The battery case of claim 1 , further including a battery lower case including a plate coupled to the side sill and front and rear barriers including a battery module mounted thereon.

16 . The battery case of claim 15 , wherein a mounting barrier is formed to protrude upwardly and formed along an edge portion of the battery module while surrounding the battery module, on a top surface of the plate.

17 . The battery case of claim 1 , wherein a rear barrier positioned in the rear portion of the floor panel is connected to a rear side member.

18 . The battery case of claim 1 , wherein a front end portion of the side sill is connected to a front side member coupled to the front portion of the floor panel.