Researchers at the Fraunhofer Institute for Applied Solid State Physics IAF have developed a gallium nitride (GaN)-based power electronics module designed for 800-volt bidirectional DC charging systems. This technology, part of the GaN4EmoBiL project, aims to improve the efficiency and compactness of electric vehicle charging by utilizing GaN semiconductors on insulating substrates to handle high power demands.
## Advancing Electric Vehicle Charging Infrastructure
The module developed by Fraunhofer IAF represents a shift in how electric vehicles interact with the power grid. By using 1,200-volt GaN devices, the system can manage battery voltages ranging from 150 volts to a maximum of 920 volts. According to the project coordinator, Jun.-Prof. Dr. Stefan Mönch, this single-phase demonstrator addresses a critical gap in the market by balancing cost, flexibility, and efficiency for bidirectional charging applications.
Unlike traditional onboard chargers, which are permanently installed in vehicles and can add significant weight and technical complexity, this off-board charger is mobile and lightweight. The complete demonstrator unit weighs 5.7 kilograms (about 12.6 pounds) and has a total volume of 8.3 liters (about 8.8 quarts). It is equipped with both CCS and Schuko plugs to enhance versatility for various charging scenarios.
## Bidirectional Charging as an Energy Solution
Bidirectional charging enables an electric vehicle to act as a mobile energy storage unit rather than just a consumer of electricity. Achim Lösch, a business developer for high-frequency and power electronics at Fraunhofer IAF, notes that this capability is a key pillar for increasing the flexibility of the energy system. When grid demand is low, the vehicle draws power; during peak periods, it can feed electricity back into the grid, helping to stabilize energy distribution.
## Technical Innovation and Future Scalability
The project focuses on achieving “wide-bandgap performance at silicon prices,” according to Dr. Michael Basler, a researcher at Fraunhofer IAF. By integrating GaN power circuits, the team is working toward greater system-level miniaturization. The researchers are also focused on scaling these technologies to accommodate higher voltage classes, increased current-carrying capacity, and larger wafer sizes.
This research is particularly relevant for the “All-Electric Society,” where efficient energy conversion is a primary requirement. Because the performance of power electronic components often limits the overall efficiency of energy systems, the use of GaN—which allows for faster and more compact designs—is viewed as a way to enhance the cost-effectiveness and range of electric vehicles.
## Industry Showcase at PCIM Expo 2026
Fraunhofer IAF is presenting its current research on GaN power electronics at the PCIM Expo & Conference, held from June 9 to June 11, 2026, in Nuremberg. The institute is showcasing the bidirectional charging demonstrator at Booth 260 in Hall 6.
The conference program includes several contributions from Fraunhofer researchers, highlighted by a keynote presentation from Dr. Michael Basler on June 9 at 9:45 a.m. titled “The GaN Evolution: Lateral, Vertical, and Bidirectional—What’s Next?” This session is scheduled to open the PCIM Conference, providing an overview of the history of GaN transistors and their future role in power electronics.