Design Optimization of Multi-material Battery Enclosure for Electric Vehicle

The lightweight design of multi-material power battery enclosure for electric vehicle was presented. The sensitivity analysis method was used to determine the contribution value of each component to the optimal target weight and the first-order natural frequency. Depending on the results of sensitivity analysis, CFRP and aluminum alloy were applied to build the structure of battery enclosure. The CFRP was used for the battery case, and aluminum alloy material for the frame structure. The size of the main bearing structures was optimized. The performance indexes under multiple loading cases, such as the strength, stiffness, first-order natural frequency and weight of the battery enclosure prototype and the multi-material battery enclosure, were compared. The results show that, on the premise of ensuring the bearing characteristics of the battery enclosure, the battery enclosure achieved the weight loss of 48.86%; meanwhile, the first-order natural frequency of it increased to 32.03 Hz.