While most Noise, Vibration, and Harshness (NVH) research on electric vehicles (EVs) focuses on conventional Cell-to-Pack (CTP) systems, the impact of Cell-to-Chassis (CTC) structures remains under-explored. A concern is that CTC architectures may compromise NVH due to the absence of a dedicated floor panel. This study investigates this concern using a comprehensive methodology: theoretical static stiffness analysis, finite element (FE) dynamic stiffness modeling, in-vehicle stiffness testing, and road noise measurements (60 km/h, rough asphalt). Simulations show the CTC structure is 20 times stiffer than a conventional CTP floor system across the 20-300 Hz frequency range, consistent with theory. Experimental in-vehicle tests reveal no correlation between local dynamic stiffness and interior noise peaks in the primary road noise frequency range (20-300 Hz). This research validates an effective simulation method for floor stiffness and demonstrates that the CTC structure’s high dynamic stiffness enables cost and weight reductions by eliminating the need for traditional floor ribs and damping layers.
Xu et al. (2026) studied this question.