The protection tray has been developed in cooperation between Rheinmetall Automotive and Rheinmetall Chempro GmbH from the Defence sector. In this project, Rheinmetall Chempro GmbH was able to optimally contribute its many years of expertise in the areas of ballistic vehicle protection and fibre composites. This was impressive: in the innovation award Losgröße 1+ of the ife Institut für Einzelfertiger, the battery protection system came in third place.
The protection tray for the underbody of the battery consists of a load-adapted fibre composite structure (CFRP/AFRP), which has been tested in extensive impact tests and numerical analyses. Weighing 14 kilograms, the intrusion protection is about 56 percent lighter than a comparable structure made of aluminium. In practice, this means that the underbody protection provides dielectric strength against blunt and sharp objects that can hit the battery at speeds of up to 150 km/h without damaging the battery floor. In addition, the battery floor is protected from static load when the vehicle is set down.
The battery pack cover, like the battery protection tray, is also made of fibre composite material. In case of a thermal runaway, this structure would keep high temperatures away from the passenger compartment. This guarantees an evacuation time of 15 minutes.
By using a material with low thermal conductivity, a flame-retardant plastic matrix as well as an additionally applied thermal protection layer, the battery pack cover meets the high thermal requirements.