German automotive parts manufacturer MAHLE developed a new highly efficient magnet-free induction motor that is more environmentally friendly to produce, is cheaper to manufacture than comparable motors, and is maintenance-free, a press statement from the Stuttgart-based firm explains.
The company says it has combined the strengths of various electric motor concepts in one product, allowing for an efficiency "above 95 percent at almost all operating points" — a level only achieved in Formula E racing cars thus far.
MAHLE explains that its "new kind of magnet-free electric motor does not require rare earth elements." This makes production better for the environment as well as bringing "advantages in terms of costs and resource security," the company says in its release.
Wear-free and highly efficient at high speeds
The new motor uses a fine-tuned design to generate torque via contactless power transmission, making it wear-free and highly efficient at high speeds.
When in use, a wireless transmitter sends an alternating electric current into the rotor. This induces a current in a receiving electrode, which in turn charges wound copper magnet coils to produce an electromagnetic field that spins the coils and generates torque.
These magnetic coils replace the permanent magnets, typically made of neodymium-boron-iron, samarium-cobalt, or ferrite, of traditional EV motors. Where these are typically placed in an EV motor, MAHLE and other designers' induction motors leave an air gap to prevent wear. MAHLE also highlights the fact that their design is easily scalable and can be used in anything from subcompact to commercial vehicles.
"With our new electric motor, we’re living up to our responsibility as a sustainably operating company," says Michael Frick, Chairman of the MAHLE Management Board (ad interim) and CFO. "Dispensing with magnets and therefore the use of rare earth elements offers great potential not only from a geopolitical perspective but also with regard to the responsible use of nature and resources."
In order to come up with their design, MAHLE said it used a state-of-the-art simulation process that allowed it to adjust and combine the parameters of different motor designs incrementally in order to settle on the optimal solution. The company says this new method allows it to "quickly create the necessary technical conditions in order to advance e-mobility in a sustainable manner worldwide."
Though the new motor design was conceived using the very latest simulation processes, the inception of induction motors dates back to the 19th century when they were invented by Nikola Tesla. A new electric vehicle development, EV-charging roads, similarly builds on the inventor's early work on alternating currents.
Reducing the EV industry's reliance on permanent magnets
The recent boom in electric vehicle uptake has seen automakers outside of China working hard to develop electric motors that don't use permanent magnets. This is due to the fact that these magnets require rare earth metals, whose mining is usually bad for the environment.
What's more, the materials are largely mined and processed in China, giving Chinese EV automakers the edge when it comes to traditional EV motors — over 90 percent of the world's rare earth elements currently come from China.
Bentley, for example, also recently unveiled an electric motor design that doesn't rely on rare earth magnets. The company revealed the motor last year in its bid to lead the charge in sustainable luxury mobility. MAHLE's is a more utilitarian approach, which makes it all the more sustainable — so all the more power to them.