The Fraunhofer Institute for Applied Solid State Physics (IAF) has unveiled a groundbreaking advancement in electric vehicle (EV) power electronics with the development of a gallium nitride (GaN)-based power electronics module tailored for 800 V bidirectional direct current (DC) charging systems. This innovative module, realized within the GaN4EmoBiL project—an initiative funded by the German Federal Ministry for Economic Affairs and Energy (BMWi)—marks a significant leap towards more efficient, compact, and versatile EV charging solutions. The module’s integration into a bidirectional, single-phase off-board charger prototype, implemented by project partner Ambibox GmbH, signals a strategic shift in the landscape of EV charging technology.
At the heart of this module lies 1200 V GaN devices crafted on insulating substrates, leveraging the superior electrical and thermal properties of GaN semiconductors. The demonstrator is designed to accommodate battery voltages ranging from 150 V to an impressive 920 V, providing a versatile platform to evaluate device performance under realistic operating conditions. Gallium nitride’s wide bandgap enables higher breakdown voltage and faster switching speeds compared to conventional silicon-based devices, delivering unprecedented efficiency and power density in a compact footprint. These characteristics are pivotal for next-generation power electronics essential to the electrification of transport and energy systems.
The bidirectional, single-phase 800 V DC charger prototype delivers up to 3 kW of power, addressing a critical market gap where traditional on-board chargers fall short in balancing cost, flexibility, efficiency, and size. EVs typically rely on on-board chargers converting AC from household or public charging infrastructures into DC at 11 or 22 kW for rapid charging. However, these on-board units are burdened by high costs, substantial weight, and significant spatial requirements due to their complex electronics and cooling systems. By relocating the charger off-board and leveraging GaN technologies, the Fraunhofer IAF and partners have engineered a lightweight (5.7 kg including plugs), compact (8.3 liters in volume), and mobile solution compatible with Combined Charging System (CCS) and Schuko plugs.
Beyond physical advantages, the charger embodies the crucial function of bidirectional charging, a technology set to revolutionize grid interaction with EVs. High-voltage reverse power flow capability enabled by the GaN module allows EV batteries to not only draw energy from the grid but also feed stored energy back during peak demand or grid stress, thus acting as distributed energy storage. This vehicle-to-grid (V2G) functionality represents a paradigm shift toward a more resilient, efficient, and sustainable energy infrastructure, integrating transportation and power networks seamlessly.
Fraunhofer IAF continues to push the boundaries of GaN power electronics, pioneering innovative device architectures and integrated power circuits that enable system-level miniaturization through functional integration. Concurrent efforts focus on scaling these technologies to higher voltage classes, larger current capacities, and increased wafer sizes to achieve cost-effective wide-bandgap semiconductor solutions on par with silicon devices. The ultimate ambition is to harness the intrinsic performance benefits of GaN while adhering to the stringent cost targets demanded by widespread commercial adoption.
The institute plans to showcase these advancements at the upcoming PCIM Expo & Conference 2026 in Nuremberg, emphasizing “Power Electronics for Energy Technology.” Presentations and exhibits will highlight a suite of GaN-based components and modules, with the bidirectional EV charging system demonstrator serving as a flagship example. A robust scientific program includes keynote speeches, technical sessions, and panel discussions led by Fraunhofer researchers, illuminating the state-of-the-art in GaN devices and prospects for future innovation.
One keynote by Dr. Michael Basler will trace the evolution from lateral to vertical and bidirectional GaN transistor configurations, outlining the technological trajectories and breakthroughs fueling enhanced power electronic performance. Complementary talks by Dr. Richard Reiner will delve into comparative device concepts and strategies for scaling the power capabilities of GaN technologies to meet the demands of 1200 V and beyond, highlighting critical design trade-offs and manufacturing challenges. Poster sessions featuring research by Jun.-Prof. Dr. Stefan Mönch and Daniel Fugmann will provide detailed insights into inverter integration and device dynamic characteristics fundamental to system optimization.
The emerging All-Electric Society paradigm hinges on continuous advancements in power electronics that can efficiently convert and store energy at ever-increasing voltages and power densities. GaN semiconductors offer transformative potential, enabling devices that operate faster, dissipate less heat, and occupy less volume than silicon counterparts. This technological edge accelerates the deployment of high-performance converters and inverters essential for EVs, renewable energy integration, and smart grid applications, thereby catalyzing the transition to sustainable energy and mobility ecosystems.
Within the domain of electromobility, GaN makes it feasible to harness power electronics operating reliably at voltages up to 1200 V, with future prospects toward 1700 V classes. This capability unlocks new architectures for EV charging infrastructure and onboard powertrains that enhance battery range, charging speeds, and system efficiency while simultaneously reducing overall costs. Collectively, these improvements promise to diversify and democratize electric mobility, extending its appeal and accessibility to a broader segment of society.
The GaN4EmoBiL project embodies a comprehensive effort to bridge the gap between research and real-world application by delivering a cost-effective, intelligent bidirectional charging platform. Research spans from novel GaN high-voltage transistors fabricated on low-cost alternative substrates to innovative bidirectional switch component concepts and integrated system implementations for both on- and off-board chargers. A critical focus on reliability and long operational lifetimes aims to meet stringent automotive standards and market expectations.
As one of the world’s foremost institutes in III-V semiconductor technologies and synthetic diamond research, Fraunhofer IAF leverages deep expertise to develop cutting-edge components for communication, mobility, quantum computing, and sensing. The institute’s integrated approach—from material science through device fabrication and system demonstration—positions it uniquely to translate GaN innovations into impactful technological breakthroughs.
The introduction of the bidirectional GaN-based charging system stands as a testament to the transformative role of wide-bandgap semiconductors in shaping the future of energy and transportation. This development not only addresses current market demands for efficient and flexible EV charging but also lays groundwork for the integration of electric vehicles as active elements within a decarbonized energy grid, aligning with global sustainability goals.
Subject of Research: Gallium nitride (GaN)-based power electronics for 800 V bidirectional DC EV charging systems
Article Title: Fraunhofer IAF Unveils GaN-Based Bidirectional 800 V DC Charger Revolutionizing EV Charging
News Publication Date: 2026
Web References:
– https://www.iaf.fraunhofer.de/en/customers/electronic-circuits/power-electronics.html
– https://www.iaf.fraunhofer.de/en/researchers/electronic-circuits/power-electronics/gan4emobil.html
– https://www.iaf.fraunhofer.de/en/networkers.html
Image Credits: © Fraunhofer IAF
Keywords
Gallium Nitride, GaN Power Electronics, Electric Vehicle Charging, Bidirectional Charging, Wide-Bandgap Semiconductors, Energy Conversion, Power Modules, Electric Mobility, Vehicle-to-Grid, Off-Board Charger, 800 V DC Charging, Semiconductor Devices
