US-20260125113-A1 - SIDE SILL STRUCTURE FOR ELECTRIC VEHICLE

Abstract

A side sill structure for a vehicle can include a sill inner member connected to each side of a floor structure at a vehicle width direction and arranged along a front-rear direction of a vehicle body, an upper reinforcing member connected to an outer surface of the sill inner member and arranged along the front-rear direction of the vehicle body, a lower reinforcing member connected to a lower surface of the upper reinforcing member and the outer surface of the sill inner member, and arranged along the front-rear direction of the vehicle body, and a sill outer member connected to the outer surface of the sill inner member and the upper reinforcing member and positioned along the front-rear direction of the vehicle body.

Inventors

• Seungho Noh
• Seung Min KANG
• Sumin Oh

Assignees

• HYUNDAI MOTOR COMPANY
• KIA CORPORATION

Dates

Publication Date

20260507

Application Date

20250829

Priority Date

20241104

Claims (20)

1. 1 . A side sill structure for a vehicle comprising: a sill inner member configured to be connected to each side of a floor structure at a vehicle width direction and arranged along a front-rear direction of a vehicle body; an upper reinforcing member connected to an outer surface of the sill inner member and arranged along the front-rear direction of the vehicle body; a lower reinforcing member connected to a lower surface of the upper reinforcing member and the outer surface of the sill inner member, and arranged along the front-rear direction of the vehicle body; and a sill outer member connected to the outer surface of the sill inner member and the upper reinforcing member and positioned along the front-rear direction of the vehicle body.
2. 2 . The side sill structure of claim 1 , wherein floor panels and cross members of the floor structure are connected on both sides of the vehicle width direction to an inner surface of the sill inner member; and wherein the cross members and the upper reinforcing member are positioned on a first imaginary line along the vehicle width direction.
3. 3 . The side sill structure of claim 2 , wherein the sill inner member is connected to a side frame on a battery-assembly side of a battery assembly mounted on a lower part of the floor structure; and wherein an upper-reinforcing-member side surface of the upper reinforcing member connected to the outer surface of the sill inner member and a side-frame side surface of the side frame are arranged on a second imaginary line along a vertical direction.
4. 4 . The side sill structure of claim 3 , wherein a section from the upper-reinforcing-member side surface of the upper reinforcing member and the side-frame side surface of the side frame to the sill outer member is a transformation section.
5. 5 . The side sill structure of claim 1 , wherein the upper reinforcing member comprises an aluminum extrusion member; and wherein the aluminum extrusion member comprises a plurality of closed sections separated by at least one barrier rib.
6. 6 . The side sill structure of claim 1 , wherein the lower reinforcing member comprises a plurality of cell assemblies connected sequentially along the front-rear direction of the vehicle body.
7. 7 . The side sill structure of claim 6 , wherein the lower reinforcing member has a honeycomb shape along the front-rear direction of the vehicle body by the cell assemblies.
8. 8 . The side sill structure of claim 6 , wherein each of the cell assemblies comprises: an upper cell body of steel material connected to a lower face of the upper reinforcing member; and a lower cell body of steel material connected to a lower part of the upper cell body and connected to the outer surface of the sill inner member.
9. 9 . The side sill structure of claim 8 , wherein the upper cell body has an M-shaped cross-section.
10. 10 . The side sill structure of claim 9 , wherein the lower cell body has a U-shaped cross-section.
11. 11 . The side sill structure of claim 8 , wherein the upper cell body comprises: an upper forming part that is concave from a top to a bottom of the upper forming part; an upper connecting part that extends forward and backward from the upper forming part and is connected to the lower surface of the upper reinforcing member; and upper rib portions each extending downward from the upper connecting part.
12. 12 . The side sill structure of claim 11 , wherein the lower cell body comprises: a lower connecting part along the front-rear direction of the vehicle body and connected to the outer surface of the sill inner member; and lower rib portions extending upward from each side of the lower connecting part.
13. 13 . The side sill structure of claim 12 , wherein the upper rib portions and the lower rib portions of each of the cell assemblies are connected by welding.
14. 14 . The side sill structure of claim 13 , wherein the upper rib portions and the lower rib portions of the cell assemblies, which are adjacent to each other along the front-rear direction of the vehicle body, are connected by welding.
15. 15 . The side sill structure of claim 8 , wherein weld nuts that penetrate the sill inner member and the lower cell body in a vertical direction are connected to the sill inner member.
16. 16 . A side sill structure for a vehicle comprising: a sill inner member configured to be connected to each side of a floor structure at a vehicle width direction and arranged along a front-rear direction of a vehicle body; an upper reinforcing member connected to an outer surface of the sill inner member and arranged along the front-rear direction of the vehicle body; a lower reinforcing member connected to a lower surface of the upper reinforcing member and the outer surface of the sill inner member, and arranged along the front-rear direction of the vehicle body, wherein the lower reinforcing member comprises a plurality of cell assemblies connected sequentially along the front-rear direction of the vehicle body; and a sill outer member connected to the outer surface of the sill inner member and the upper reinforcing member and positioned along the front-rear direction of the vehicle body.
17. 17 . The side sill structure of claim 16 , wherein each of the cell assemblies comprises: an upper cell body connected to a lower face of the upper reinforcing member, wherein the upper cell body has an M-shaped cross-section; and a lower cell body connected to a lower part of the upper cell body and connected to the outer surface of the sill inner member, wherein the lower cell body has a U-shaped cross-section.
18. 18 . A vehicle comprising: a floor structure; and a side sill structure comprising: a sill inner member connected to each side of the floor structure at a vehicle width direction and arranged along a front-rear direction of a vehicle body, an upper reinforcing member connected to an outer surface of the sill inner member and arranged along the front-rear direction of the vehicle body, a lower reinforcing member connected to a lower surface of the upper reinforcing member and the outer surface of the sill inner member, and arranged along the front-rear direction of the vehicle body, and a sill outer member connected to the outer surface of the sill inner member and the upper reinforcing member and positioned along the front-rear direction of the vehicle body.
19. 19 . The vehicle of claim 18 , wherein the floor structure comprises floor panels and cross members, wherein of the floor panels and the cross members are connected on both sides of the vehicle width direction to an inner surface of the sill inner member; and wherein the cross members and the upper reinforcing member are positioned on a first imaginary line along the vehicle width direction.
20. 20 . The vehicle of claim 19 , further comprising a battery assembly mounted on a lower part of the floor structure, wherein the battery assembly includes a side frame on a battery-assembly side of the battery assembly, and wherein the sill inner member is connected to the side frame; and wherein an upper-reinforcing-member side surface of the upper reinforcing member connected to the outer surface of the sill inner member and a side-frame side surface of the side frame are arranged on a second imaginary line along a vertical direction.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority to and the benefit of Korean Patent Application No. 10-2024-0154059 filed with the Korean Intellectual Property Office on Nov. 4, 2024, the entire contents of which are incorporated herein by reference. TECHNICAL FIELD The present invention relates to a side sill structure for an electric vehicle. BACKGROUND Recently, due to environmental regulations and fuel efficiency regulations, the use of electric vehicles driven by electric power sources is increasing. Electric vehicles are equipped with a battery assembly that supplies electricity to the electric drivetrain. The battery assembly, in one example, is mounted on the lower portion of the floor structure in the vehicle body of an electric vehicle. For electric vehicles, the main factor affecting the range (or travel distance) is the battery volume ratio of the battery assembly. The more battery cells that can be installed in the limited space of the battery assembly, the greater the range of the electric vehicle. Battery volume ratio may be deteriorated due to components with overlapping mechanical strength between the vehicle body and the battery assembly (e.g., side components of the battery assembly that are connected to the vehicle body) and battery mount components of the battery assembly. On the other hand, as the demand for electric vehicles has increased recently, the development of a vehicle body that can satisfy collision performance is required. In particular, there is a need for the development of a vehicle body that can protect the battery assembly in the event of a side collision of an electric vehicle. The information contained in this Background section is intended to promote understanding of the background of the present disclosure and may include matters that are not conventional art already publicly known, available, or in use. SUMMARY The present disclosure relates to a vehicle body structure for an electric vehicle, and more particularly, the present disclosure relates to a side sill structure for an electric vehicle with improved lateral collision performance. An embodiment of the present disclosure can provide a side sill structure for an electric vehicle that can minimize side sill rotation and reduce collision energy transmitted to a battery assembly in a side collision of the electric vehicle. A side sill structure for an electric vehicle according to an embodiment of the present disclosure may include a sill inner member connected to each side of a floor structure along a vehicle width direction and arranged along a front-rear direction of a vehicle body, an upper reinforcing member connected to an outer surface of the sill inner member and arranged along the front-rear direction of the vehicle body, a lower reinforcing member connected to a lower surface of the upper reinforcing member and the outer surface of the sill inner member, and arranged along the front-rear direction of the vehicle body, and a sill outer member connected to the outer surface of the sill inner member and the upper reinforcing member and positioned along the front-rear direction of the vehicle body. Floor panels and cross members provided in the floor structure may be connected on both sides along the vehicle width direction to an inner surface of the sill inner member. The cross members and the upper reinforcing member may be placed on a first imaginary line along the vehicle width direction. The sill inner member may be connected to side frames on both sides of a battery assembly mounted on the lower part of the floor structure. A side surface of the upper reinforcing member connected to the outer surface of the sill inner member and a side surface of the side frame may be arranged on a second imaginary line along the vertical direction. A section from the side surface of the upper reinforcing member and the side surface of the side frame to the sill outer member may be set as a transformation section. The upper reinforcing member may include an aluminum extrusion member. The aluminum extrusion member may include a plurality of closed sections separated by at least one barrier rib. The lower reinforcing member may include a plurality of cell assemblies connected sequentially along the front-rear direction of the vehicle body. The lower reinforcing member may be formed in a honeycomb shape along the front-rear direction of the vehicle body by the cell assemblies. The cell assemblies may include an upper cell body of steel material connected to the lower face of the upper reinforcing member, and a lower cell body of steel material connected to the lower part of the upper cell body and connected to the outer surface of the sill inner member. The upper cell body may be equipped with an “M” shaped cross-section. The lower cell body may be equipped with a “U” shaped cross-section. The upper cell body may include an upper forming part that is formed concavely from the top to the bottom,