What EV projects are the researchers of Volkswagen’s Knoxville Innovation Hub working on?

AI-optimized material structures to increase EV range

Researchers are working on new material structures which reduce weight and helps to increase the range of EVs.

As a first pilot, the team has chosen the steel frame that houses the EV battery pack in the vehicle and shields it from physical impacts.

With artificial intelligence with up to millions of parameters on UT’s high performance compute cluster, the team has developed a modular repeating structure in shapes of tiny pyramids.

The structure can be 3D printed from liquid resins and holds 30,000 times its own weight of 68g. The newly created frame would be up to 60% lighter.

Hardcore durability tests showed that it exceeds the conventional steel frame in energy absorption, which could serve as a lightweight, but ultra-robust alternative.

Paper-based materials for vehicle interior

The team is developing paper-based, recyclable materials as alternatives to plastic parts and foils in vehicle interior. The key is a patented method of performing and hot-pressing cellulose fiber reinforced thermoplastics into the durable interior parts.

Not only recyclable, the paper-based composites can also be transformed into various interior shapes and sizes, including backlit and ambient light options. 

The team has also innovated ways to add different textures and colors, in order to allow flexibility and creative freedom for vehicle interior designs.

New fiber composites for lightweight vehicle parts

Volkswagen team started the lightweight material research by recreating the lift gate of a Volkswagen vehicle using sheet molding compound (SMC), a type of fiberglass reinforced plastic.

The new lift gate proved to be 13 pounds lighter than the conventional metal-based version, saving more than 35% weight, which helps to increase the range of EVs and vehicles powered with a combustion engine.

In addition, the alternative composite lift gate does not require changes in assembly sequence compared to conventional versions, meaning those components are fit for high volumes.

This result has already been applied into vehicle production – Bentley and Lamborghini have adopted these new materials and molding process for Bentley Continental and Lamborghini Aventador.

More recently, Volkswagen and UT researchers have further refined molding processes and ways to optimize durability, quality and design options. A specific take is to optimize the fiber-matrix-interface, a process called “sizing”, essentially creating the smoothest, most durable coat for fibers possible.

New pad design for more efficient EV charging

The team has patented a unique coil and charging pad design with silicon-carbide materials to optimize charging speed and safety for easier EV charging. In the first trial with a silicon-carbide inverter, the prototype system has shown high efficiency.

With Volkswagen’s expertise in vehicle power electronics, UT’s knowledge of power electronics optimization and ORNL’s capabilities in high power wireless charging, the research team has been able to increase the charging power level up to 120kW with this prototype from an earlier 6.6kW prototype.

The team’s future goal is 300kW.