Forvia Hella and Tau Motors join forces to develop a transformer-less onboard charger that promises higher efficiency, lighter weight, and smarter energy management for EVs.
Forvia Hella, an international automotive supplier, and Tau Motors, a pioneer in software-defined power conversion, have announced a strategic development partnership to deliver advanced charging solutions for electric vehicles. The collaboration focuses on the development of a virtually isolated Onboard Charger (viOBC), with series production planned within two to three years. The partnership also includes an investment in Tau via Hella Ventures.
At the core of the innovation is a transformer-less design, which eliminates the need for galvanic isolation between the AC grid and the DC vehicle system through a combination of advanced hardware and software. Despite removing the transformer, the viOBC maintains complete electrical and functional safety, while offering notable advantages in efficiency, power density, and compactness.
The viOBC achieves a power density of up to 7kW per litre and delivers energy efficiency exceeding 98 per cent. Its compact build reduces installation space by up to 50 per cent and lowers weight by around 33 per cent. Additional features include bidirectional charging and vehicle-to-grid integration, enhancing energy management within vehicles. These efficiencies are expected to contribute to lower CO2 emissions and reduced electricity costs for users.
A prototype has already passed both technological and commercial testing phases, confirming readiness for industrialisation. Forvia Hella brings expertise in high-voltage and power electronics and mass production capabilities, while Tau Motors contributes its software-defined technology platform, power electronics knowledge, and innovative product design.
Jörg Weisgerber, Managing Director Electronics at Forvia Hella, said: “The collaboration takes onboard charging to the next level and creates a product that sets new standards in power density. viOBCs represent another significant contribution to sustainable mobility and strengthen our position as an innovation leader.”
Wesley Pennington, Founder and CEO of Tau, added: “This partnership aligns groundbreaking technology with industrial excellence to deliver the next generation of high-voltage power electronic and energy management solutions for clean, intelligent mobility.”



















