EV battery crash protection using high strength steels

EV battery enclosures made using 3D roll-formed UHSS steel

One part of the Docol^® EV Design Concept is to use 3D roll-formed beams in Docol^® 1700 martensitic steel that are woven into a “mesh” structure for the bottom of a battery enclosure. The mesh structure maintains distance between the battery enclosure’s bottom plate and its tray, protecting the battery cells from intrusions coming in the Z direction.

The beams in blue are 3D roll-formed in Docol^® 1700M. The profiles in the X-direction are the same as in Y-direction, but turned upside down to reduce the mesh’s height by a factor of two, enabling more leg room in the passenger compartment.

Energy-absorbing AHSS beam for EV sill rocker

EVs must absorb more energy through their sills than ICE models due to the weight of the battery pack, the EV’s stiffer underbody, and the higher protection requirements for the battery. Extruded aluminum sill beams made from EN AW-6082 T6 are an efficient way of absorbing higher energy levels on side impacts – but at a premium price. 

SSAB has run numerous simulations for 2D roll-formed sill beams made in Docol^® CR 1700M steel, adjusting the wall thicknesses so each profile would weigh the same as the 6082-aluminum beam. The best 1700M profile had similar crash performance results as the 6082-aluminum beam.

Plotting force vs. displacement for nine different Docol 1700M profiles for EV sill beams. To see the profiles of the sill beams tested here, including the best performing profile, contact Docol.