YASA Electric Motor Acquired by Mercedes-Benz

YASA Acquisition by Mercedes-Benz: A Deep Dive into Axial-Flux Motor Technology

In July, Mercedes-Benz completed the acquisition of YASA (formerly Yokeless And Segmented Armature), a UK-based startup specializing in innovative electric motors. While the announcement received limited widespread coverage, YASA represents a potentially significant development within the electric vehicle industry.

Origins and Future Development

Established in 2009 as a spin-off from research conducted at Oxford University, YASA will now focus on developing advanced, high-performance electric motors specifically for Mercedes-Benz’s AMG.EA all-electric platform.

The company will continue to operate as a wholly-owned subsidiary within the U.K., maintaining its existing brand identity, team, facilities, and location in Oxford. Furthermore, YASA will continue to serve current clients, including Ferrari, alongside its new partnership with Mercedes-Benz.

The Advantages of Axial-Flux Motors

YASA’s axial-flux electric motors have garnered attention due to their superior efficiency, high power density, compact size, and reduced weight. These characteristics position them as a compelling alternative to conventional motor designs.

The majority of electric vehicles currently utilize “radial” electric motors, a technology that is over 40 years old. Even Tesla employs this established design, suggesting limited potential for further substantial innovation within this framework.

However, YASA’s axial-flux design, characterized by its exceptionally thin segments, allows for the creation of powerful, integrated drive units. These motors are demonstrably lighter – approximately one-third the weight of comparable electric motors – and exhibit three times the power density of those found in Tesla vehicles.

Insights from YASA’s Founder and CTO

Tim Woolmer, the founder and Chief Technology Officer of YASA, pioneered this novel approach to electric motor design. A recent discussion with Woolmer revealed insights into the company’s trajectory and future ambitions.

TC: Could you outline the company’s progress to date?

TW: Over the past twelve years, our primary objective has been to accelerate the adoption of electric vehicles. We believe that within the next decade, all new car sales will be electric, and we are dedicated to making that transition happen more rapidly. This period of revolution offers engineers an unparalleled opportunity for innovation, and our collaboration with Mercedes-Benz is particularly exciting in this regard.

What distinguishes the motor you developed?

Our development began with a fresh perspective during my doctoral research. We aimed to anticipate the future needs of the electric car industry – a motor that was lighter, more efficient, and capable of large-scale production. Axial-flux motors were relatively uncommon in the 2000s, but by integrating this technology with specific material advancements and design refinements, I developed what we now call YASA: Yokeless And Segmented Armature. This design further reduces weight by approximately 50%. The larger rotor diameter also contributes to increased torque, as torque is directly proportional to diameter.

Following the agreement with Mercedes, what are the next steps for YASA?

We are now a fully owned subsidiary and will leverage Mercedes-Benz’s extensive industrialization capabilities. Historically, automotive technologies often originate in the luxury segment, such as vehicles from Ferrari, before becoming more widely adopted. Mercedes-Benz excels in industrialization, making this partnership strategically advantageous.

What further possibilities does this open up for YASA?

We are positioned to deliver engines that are exceptionally powerful, lightweight, and have a low density. This allows us to explore applications in high-performance sports cars while maintaining a focus on efficient industrial production, creating a unique market position.

Looking Ahead

While remaining reserved about specific future plans, Tim Woolmer is undoubtedly a key figure to observe in the evolving landscape of electric vehicles and motor technology. Following the acquisition, YASA released a video showcasing their technology: https://www.youtube.com/watch?v=YkldZQuzR3E