New Magnet-Free Electric Motor That Needs No Maintenance

MAHLE, a renowned German automotive parts manufacturer, has made significant strides in the development of a highly efficient magnet-free induction motor. This innovative motor not only demonstrates enhanced environmental sustainability in its production process but also boasts cost advantages and maintenance-free operation. According to a press statement from MAHLE, the company has successfully integrated the strengths of various electric motor concepts into a single product, achieving an impressive efficiency level of “above 95 percent at almost all operating points.” This level of efficiency has thus far only been observed in Formula E racing cars.

One of the standout features of MAHLE’s new magnet-free electric motor is its independence from rare earth elements. Unlike traditional electric motors that rely on permanent magnets composed of neodymium-boron-iron, samarium-cobalt, or ferrite, this innovative design replaces them with magnetic coils. By eliminating the need for rare earth elements, MAHLE not only improves the environmental impact of production but also offers cost and resource security advantages. Additionally, the motor’s fine-tuned design enables contactless power transmission, resulting in a wear-free and highly efficient performance, particularly at high speeds.

The motor operates by utilizing a wireless transmitter that sends an alternating electric current into the rotor. This process induces a current in a receiving electrode, subsequently charging wound copper magnet coils. As a result, an electromagnetic field is generated, which in turn spins the coils and generates torque, propelling the motor’s operation.

MAHLE emphasizes that its induction motor design incorporates an air gap, preventing wear and enabling scalability. This design flexibility allows the motor to be applied to a wide range of vehicles, from subcompact cars to commercial vehicles.

Michael Frick, Chairman of the MAHLE Management Board (ad interim) and CFO, states that the development of this new electric motor reflects the company’s commitment to sustainable practices. Frick highlights the elimination of magnets and rare earth elements, which not only holds geopolitical significance but also demonstrates responsible utilization of nature and resources.

To achieve this breakthrough design, MAHLE utilized state-of-the-art simulation processes. Through an iterative approach, the company adjusted and combined different motor parameters until arriving at the optimal solution. This simulation-driven methodology empowers MAHLE to swiftly create the necessary technical conditions to advance global e-mobility sustainably.

While the design process for the new motor relied on cutting-edge simulation techniques, the concept of induction motors traces its roots back to the 19th century when Nikola Tesla first invented them. Interestingly, another development in electric vehicle technology, EV-charging roads, also draws inspiration from Tesla’s pioneering work on alternating currents.

The quest to reduce the electric vehicle industry’s dependence on permanent magnets has gained significant momentum. Automakers worldwide, particularly those outside of China, have been diligently exploring alternatives that do not require rare earth metals. The environmental impact associated with mining these metals has raised concerns. Moreover, China currently dominates the rare earth element market, with over 90 percent of global production originating from the country.

Bentley, for instance, recently unveiled its own electric motor design that eliminates the need for rare earth magnets. The luxury automaker showcased this motor as part of its commitment to leading sustainable luxury mobility. In contrast, MAHLE’s magnet-free motor offers a more utilitarian approach, further enhancing its overall sustainability. Thus, the company deserves commendation for its contribution to the field of electric motor innovation and sustainable transportation.