Performance analysis and optimization design of integrated battery box structure for electric cargo vehicles

Abstract

The lightweighting of the power battery compartment for electric cargo vehicles is of great significance for enhancing their driving range and safety. An integrated design scheme for the battery compartment and frame of an electric cargo vehicle was presented in this study. The finite element model (FEM) of the integrated structure was established, and the stiffness and strength of the battery compartment under four typical static working conditions, as well as the vibration mode and frequency under constrained mode conditions were analyzed. The accuracy of the established FEM was verified through the bending and torsional stiffness tests of the frame. Then, the mechanical shock, simulated collision, compression and random vibration performance of the battery compartment were analyzed, and the evaluation indicators were established. Finally, the morphology optimization of the outer skin of the battery compartment and the multi-objective optimization design of the frame structure size was carried out. The weight of the battery compartment had been reduced by 16.9% after optimization, the maximum stress during simulated collisions was reduced by 20%, and the maximum deformation decreased by 50%, this enabled the simulated collision performance to meet the standard requirements. Meanwhile, all other performance indicators of the battery compartment also met the standards. This research provides reference and guidance for the development of a brand-new architecture for electric commercial vehicles.