Volkswagen Group of America is deepening its advanced materials research in the USA. The OEM has sites across the country and works with universities and federal research institutes in various areas of interest. Materials science experts at Volkswagen’s Innovation Hub in Knoxville, Tennessee, are working with faculty and doctoral students from the University of Tennessee (UT) and scientists from Oakridge National Lab (ORNL) on various projects to enrich knowledge and engineer solutions in lightweight composites, recyclable interior materials and EV wireless charging technology. The facility, which opened in 2020, is situated at the University of Tennessee Research Park in a region referred to as ‘materials valley’ due to the concentration of research facilities, including the ORNL.
“We are accelerating innovation within electric vehicles and contributing to more sustainable transportation in America by focusing our efforts on some of the most transformative automotive research being done in the country,” said Pablo Di Si, president and CEO at Volkswagen Group of America.
“Our technology teams in Tennessee are a great example. There we are tapping American ingenuity fostered by the unique blend of world-class academic research and Volkswagen’s leading industry capabilities. Centering more knowledge in the United States is part of Volkswagen’s strategy for growth and is vital for sourcing and developing talent.”
UT chancellor Donde Plowman said, “The Volkswagen Innovation Hub is a powerful example of the kind of scientific advances and industry-ready technology that you can bring to market when you locate scientists and researchers from across disciplines and organizations together in one place. With partners like Volkswagen, Oak Ridge National Lab, and others industry leaders and tech startups located at UT’s Research Park, we have created a thriving innovation ecosystem.”
Projects in a nutshell
AI-optimized material structures
Volkswagen researchers are investigating new material structures to reduce vehicle weight. For its first pilot, the team is focusing on the steel frame that houses the battery pack in the vehicle and shields it from physical impacts.
By running a deep learning algorithm with up to millions of parameters on UT’s high-performance compute cluster, experts have developed a modular repeating structure in shapes of tiny pyramids. This structure can be 3D printed from liquid resins and holds 30,000 times its own 0.15 lb weight (68g). A frame made from the material could be up to 60% lighter. Hardcore durability tests showed that it exceeds the conventional steel frame in energy absorption, and could serve as a lightweight, yet ultra-robust alternative, according to VW.
The team at UT’s Center for Renewable Carbon is developing recyclable alternatives to interior plastic parts and foils, focusing on paper. A method of preforming and hot-pressing cellulose fiber-reinforced thermoplastics into interior parts has been patented. These paper-based composites are not only recyclable, they can also be transformed into various interior shapes and sizes, including backlit and ambient light options. The specialists have also devised ways to add different textures and colors.
They began by recreating the lift gate of a MY2020 Volkswagen Atlas using sheet molding compound, a type of fiberglass reinforced plastic. The new lift gate proved to be 13 lb lighter than the conventional metal-based version; a weight saving of more than 35%. In addition, the alternative composite lift gate does not need changes in assembly sequence compared to conventional versions, meaning those components are fit for high volumes.
VW is assessing opportunities to include these paper-based interior parts in future model lines and how to introduce them on a mass scale. However some of these solutions have already been applied in mass production vehicles; Bentley and Lamborghini have adopted the new materials and the molding process in the Bentley Continental and in the Lamborghini Aventador.
The team in Knoxville is also exploring lightweight options for pickup beds and rugged components.
More recently, Volkswagen and UT researchers have further refined molding processes and ways to optimize durability, quality and design options. One specific learning is to optimize the fiber-matrix-interface in a process called sizing, which is essentially creating the smoothest, most durable coat for the fibers as possible.
Furthermore, as a result of the advanced materials research, VW has patented a unique coil and charging pad design made from silicon-carbide materials that is said to improve charging speed and safety. In early trials with a silicon-carbide inverter, this prototype system was shown to be highly efficient. Combining Volkswagen’s expertise in vehicle power electronics, ORNL’s capabilities in high-power wireless charging and UT’s knowledge of power electronics optimization, the research team has been able to increase the charging power level up to 120kW with this prototype from an earlier 6.6kW prototype. Their future goal is to achieve 300kW.
Volkswagen’s Innovation Hub Knoxville significantly contributes to VW Group’s worldwide R&D web, which also includes tech hubs in Belmont, California; Wolfsburg, Germany; Beijing, China; Singapore; Tel Aviv, Israel; and Tokyo, Japan.