Crashworthiness Rangka Baterai Kendaraan Listrik dengan Balok Samping Fractal Multi-Cell pada Tumbukan Lateral

Abstract

Traction batteries are located close to the vehicle underbody, so side-structure deformation can directly threaten the battery-cell space. This work evaluates the lateral-impact performance of an electric-vehicle battery frame by comparing a conventional hollow side beam with a Fractal Multi-Cell Square Tube (FMST). Eighteen LS-DYNA models were evaluated from two geometries, three materials (Aluminium 6061-T6, Aluminium 7075-T6, and annealed Steel 4340), and three outer-wall thicknesses (1.5, 2.0, and 2.5 mm). Performance was assessed using energy absorption, lateral intrusion, mean crush force, and specific energy absorption. A 6 mm element size differed by only 0.043% in absorbed energy from the 3 mm mesh, while all models maintained an energy ratio near unity and hourglass energy below 0.8%. The FMST consistently reduced intrusion, although it did not increase total energy absorption. The 2.5 mm FMST-Steel 4340 configuration produced the lowest maximum intrusion (54.2 mm) and the highest mean crush force (101.2 kN). In contrast, the 1.5 mm Baseline-Aluminium 6061-T6 configuration achieved the highest specific energy absorption (0.663 kJ/kg). The results identify a direct trade-off between intrusion protection and structural mass efficiency, indicating that the preferred battery-frame configuration depends on the governing safety and weight requirements.