Abstract: The insufficient mileage is one of the major bottleneck factors which affect the promotion and
application of electric cars. To reduce the electric vehicle body mass is an effective way to improve the mileage
of an electric vehicle. Two kinds of contraction beams, straight retractable (SR) and tapered retractable (TR)
beams, were designed to lighten the electric car mass. A frontal crash model was established by using the
Hypermesh and LS-DYNA to study the frontal structural component crashworthiness of an electric car during
collisions at a low-speed of 16 km/h and a high-speed of 50 km/h. The collision energy absorption, the impact
force, and the body acceleration, when using new energy-absorbing beams, were analyzed and compared
with those when using the original energy-absorbing beam. Simulation results demonstrate that the straight
retractable beam can absorb more crash energy by 18.0% at the high-speed collision and reduce the mass by
23.6%, which optimizes both the light mass and the crashworthiness of an electric car.

Key words: electric car, energy-absorbing beam, crashworthiness, light mass