Mercedes-Benz revealed a futurist hypercar concept called Vision 111 in Carlsbad, Calif. this week. While it pays homage to the iconic C111 prototypes of the previous century with its sleek look and gullwing doors, the real advancement, just like the C111, is with the powertrain technology.
For the Vision 111, the German automaker is talking about designing the vehicle around smaller, lighter and more powerful electric motors mounted right on the wheels. The car we see doesn’t have these motors in it now.
Because the axial-flow motor is a third of the weight and a third of the volume to create the same power, “we could imagine it to be part of the wheel and the unsprung mass, which is critical,” said Konstantin Neiss, chairman of YASA and head of drive unit development for Mercedes-Benz.
Wheel-mounted motors are arguably the holy grail of EV development, but are not currently viable because they increase unsprung weight, weight is not supported by a vehicle’s suspension, which is an enemy of suspension design. Lighter AF motors could resolve that issue, not only in and of themselves but also by allowing smaller friction brakes, because the motors in regenerative systems do much of the braking.
As well, Neiss said, “you get rid of the driveshaft weight, of the central drive unit weight, by placing the motors onto the wheels. So there may also be an overall weight advantage on the vehicle. And the most obvious advantage is that you gain good space in the center of the vehicle for either placing battery packs or other technical components, or you can simply use it for more space for the customer or the trunk or wherever.”
Developed originally by YASA Ltd., a British electric vehicle motors startup founded by Oxford-grad Tim Woolmer and now owned by Mercedes, the motors use axial-flux (AF) stator technology rather than the radial-flux (RF) system that is the industry standard in EVs (the YASA name derives from Yokeless and Segmented Armature, a reference to part of the motor’s architecture).
Owing to a new, mouldable material called soft magnetic composite and other innovations, YASA says it overcame the cooling issues and the manufacturability challenges that have so far kept axial-flux designs on the sidelines. The firm’s motors powered the prototype that in 2015 became the first EV to win the Pike’s Peak Hillclimb, and are also used by Ferrari in its electrified production models.
For now, the Vision 111 has been conceived to go either with central or wheel-mounted motors. “That’s why the Vision is shown this way,” said Neiss. “It kind of implies we have two options, similar to the C111 where we had the Wankel engine technology and the diesel engine technology.”
In the 1960s and 70s, Mercedes built a series of C111 prototypes, which were ultra-aerodynamic mid-engine cars that set a series of closed-course speed records. They were initially powered by a Wankel rotary engine, then a turbo-diesel and finally by a turbocharged gasoline V8.
Mercedes has no plans for a production version of the Vision 111 and the first production application of the YASA motors – expected to be in a sports car – will be centrally mounted, Neiss said. Meanwhile, it was also revealed, the company continues to improve its radial-flux motors, and a new generation of RF motors will power the small EV cars and crossovers coming next year on Mercedes’ new MMA architecture.
The Vision 111 reveals capped off a symposium where Mercedes showcased the brand’s position and its future in the world of luxury. Included in that showcase were our first in-the-metal encounter with the new 2024 E-Class sedan and its available Superscreen, NFT artworks, augmented reality and personalized user-interface graphics.
The writer was a guest of the automaker. Content was not subject to approval.