The German manufacturer SGL Carbon and the Chinese electric car manufacturer Nio have developed a prototype of a battery housing made of carbon fiber reinforced plastic (CFRP) for electric vehicles. It is around 40% lighter than comparable aluminum housings.
Other advantages cited by the partners are the high rigidity of the battery box and the approximately 200 times lower thermal conductivity of CFRP compared to aluminum, which better protects the battery against cold and heat. In addition, the composite material scores points for water and gas tightness and corrosion resistance. The background to the Sino-German cooperation is Nio’s interchangeable battery approach. The newly developed battery box and battery can be changed within three minutes at Nio’s own exchange stations, according to an accompanying press release. Nio presented the prototype together with other technological innovations at the latest Auto Shanghai.
As SGL Carbon specifies, the construction of the base and the lid is decisive for the properties of the battery box: a sandwich core is combined with several layers of carbon fiber. The carbon fiber for this is produced in the SGL plants in Moses Lake and Muir of Ord and processed into scrims in Wackersdorf. According to the manufacturer, the production of the bottom and lid as well as the assembly of the individual components takes place at the Ried site in Austria.
“Lightweight technology is one of the core elements in NIO technology roadmap,” says Bin Wei, Senior Manager Lightweight Engineering at Nio. “Using composite material especially the high-performance carbon fiber in battery enclosure system, our vehicle can achieve better dynamic performance, increase range, and obtain remarkably high energy density of the battery pack (over 180 Wh/kg). ”
Meanwhile, SGL Carbon anticipates that the demand for lightweight solutions for battery boxes will increase sharply with the ramp-up of electromobility, and is already working with various partners on the further development of composite battery boxes that will be scalable for batteries of all sizes and designs in the future.