New magnet-free electric motor increases the performance of the electric vehicle and reduces CO2 emissions

Two companies have collaborated to expand the product range of magnet-free electric motors to high-end applications.

Valeo and MAHLE will develop an innovative magnet-free electric axle system aimed at high-end electric vehicles with peak outputs of 295 to 469 hp (220 kW to 350 kW).

According to the company, Valeo's technology is based on the successful joint development of magnet-free electric motor technology (EESM – Externally Excited Synchronous Motor) with a European OEM.

Cutting-edge technology can increase the efficiency of magnet-free electric motors

The companies are introducing an internal brushless electric excitation (iBEE) system, a cutting-edge technology that they say can revolutionize the performance and efficiency of magnet-free electric motors.

“This collaboration with MAHLE is a perfect fit. MAHLE is developing the EESM rotor and its brushless excitation system,” said Xavier Dupont, CEO of Valeo Power Division.

Dupont emphasized that Valeo provides dedicated control of this electric motor and the brushless system integrated into the inverter.

This partnership allows Valeo to complete its high-end EESM portfolio and, according to Dupont, is crucial to supporting the automotive industry's evolution towards more innovative, sustainable solutions.

Innovative cooling concept is to be developed

Both companies have signed a joint development agreement to combine Valeo's expertise in electric motors, high-efficiency inverters and associated motor control laws, as well as MAHLE's expertise in magnet-free rotors with its MAHLE Contactless Transmitter (MCT) technology.

In order to achieve an excellent long-term peak performance ratio, the companies are working on an innovative cooling concept.

Additionally, the carbon footprint is expected to be reduced by more than 40% compared to a permanent magnet electric motor of equal power, the companies said in a press release.

The first prototypes are expected to be completed by the end of 2024

Testing of the first prototypes is scheduled to be completed by the end of 2024.

Valeo's first EESM development is based on a collaboration with a European OEM started in 2022 to create a new generation of magnet-free electric motors (EESM).

The company claimed the project's initial goals were twice as high; First, the company received an all-in-one architecture with new stator and cooling technology to increase power density by 30% compared to the current engines equipped on current OEM vehicles on the road.

Secondly, the carbon footprint is said to be reduced by 30% compared to a magnet-equipped electric motor (PMSM).

The company also claimed that a validation phase lasting more than six months was successfully completed, with results in terms of performance and efficiency exceeding initial expectations, particularly thanks to Valeo's inverter expertise.

“The performances correspond to the level of permanent magnet electric motors for B/C segment vehicles and offer all the advantages of magnet-free technology (no rare earths, lower carbon footprint…),” Valeo said in a press release.

Electric drive systems

MAHLE stated that it had focused on the development of electric drive systems. Its contactless transmission technology for magnet-free electric motors is considered a key factor for the next development of EESM-based e-axles.

The company emphasized that avoiding the use of rare earths not only makes a positive contribution to the sustainability of e-mobility, but also has advantages in terms of costs and resource security.

According to MAHLE, the core is the inductive and therefore non-contact and wear-free power transmission, which enables engine operation at benchmark efficiency levels.

Martin Wellhoeffer, member of the MAHLE Group management, explained that the new e-axis will benefit from MAHLE's expertise in contactless encoder technology.

“Together we will set new standards in terms of packaging and efficiency for EESM-based e-axles and take the next step towards future mobility for our customers,” said Wellhoeffer.