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