US Patent 10476061 Electric vehicle cabin floor structure

Provided herein are apparatus, systems, and methods for reducing noise in an electric vehicle. The apparatus can include a cabin floor, a battery pack, and a stiffener positioned between the cabin floor and the battery pack. The cabin floor can include a recess that that defines a volume in the cabin floor. The battery pack is coupled to the cabin floor, and includes a plurality of battery cells generating a voltage and a current. The stiffener includes a first stiffener surface that faces the cabin floor, a second stiffener surface that faces the battery pack, and a first stiffener element that extends out of the first stiffener surface and conforms to a shape of the recess. The first stiffener element is positioned on the first stiffener surface to align with a position of the recess in the cabin floor.