The growing number of electronic systems in modern cars and the integration and protection of batteries in electric vehicles play a crucial role in development and manufacturing. Electric cars must be designed in such a way that, in the case of an accident, batteries remain intact to protect passengers and rescue teams from risks such as high voltage tension or leaking substances.
The sheer number and size of battery pack units in electrical vehicles is a major challenge for automotive designers seeking to meet strict crash performance requirements. In many cases, the battery pack tray extends across the entire underbody area between the wheels and must be protected against impact from all sides.
Fig. 1: ”Typical configuration of EV battery pack units in tray on vehicle underbody"
Fig. 2: ”US NCAP pole crash scenario at 32 km/h and 75° after 45 ms"
Optimizing the rocker panel design
One of the key components for protecting the batteries on the underbody in the event of a crash is the rocker panel or sill that extends along the sides of the tray supporting the battery packs. Premium vehicle OEMs normally specify the intrusion in a side crash scenario, according to the US NCAP pole test at 32 km/h at 75°, to stay below 10 mm.
In a collaborative approach, Henkel and RLE International showed that battery crash protection can be optimized by using hybrid structural parts, based on a combination of fiber-reinforced plastics (FRP) and specially developed high-performance structural foam.
Fig. 3: ”Design principle of hybrid structural parts combining a carrier molded in fabric-reinforced plastic with Teroson EP1450 structural foam sections for added stiffness"