A recently published patent application from Ferrari hints at wheel motors for future high-performance road cars.
In a filing published by the United States Patent and Trademark Office (USPTO) on November 2, 2023, submitted in the previous April, the Italian high-performance car manufacturer seems to be working on integrating motors with friction brakes as part of a car’s wheel assembly.
Ferrari is developing axial flow motors, but the application discusses the more traditional type: the permanent magnet radial flow synchronous type.
As described in the application, the stator would be part of the wheel hub, while the rotor would be attached to the wheel rim. This would also incorporate the brake disc as part of the assembly, with the disc and rotor separated by a spacer.
Ferrari claims that this design reduces cost and complexity by limiting the number of additional components needed for a wheel motor. The carmaker also asserts that it can address any issues caused by the additional unsprung weight that comes with wheel motors through the design and tuning of the suspension. It describes the use of electromagnetic sensors to provide more precise control over power flow, which could be a significant differentiator.
Ferrari is not the first high-performance car manufacturer considering wheel motors. Earlier this year, McLaren announced that it is developing a “wheel propulsion system” combining McLaren Applied Technologies’ racing expertise with Elaphe’s wheel technology for “hypersensitive electric vehicles.”
Other applications have focused less on performance. Lightyear claimed to have the world’s most efficient EV powertrain with wheel motors, also from Elaphe, but the Lightyear 0 EV did not make it to the production stage.
Lordstown Motors also used Elaphe motors in the wheels, licensing the technology for its Endurance electric truck. The Endurance briefly entered production, but few were built before Lordstown filed for bankruptcy. Elaphe has another customer: Aptera, which in 2019 announced it would use the company’s motors for its three-wheeled vehicle. Aptera has said the vehicle is getting closer to production readiness but hasn’t provided a firm schedule.
Apart from all this, Chinese automaker Dongfeng claimed earlier this year to have the world’s first regular production passenger car with wheel motors, from supplier Protean. The Dongfeng Fengshen E70 only uses wheel motors to drive its rear wheels, however, with a conventional internal motor driving the front axle.
