Yasa unveils 550 kW axial-flow electric motor weighing 13.1 kg

The potential of axial-flow electric motors is enormous, and it has just grown further. Britain’s Yasa, a Mercedes-Benz subsidiary that already supplies these motors for Ferrari and Lamborghini hybrids, has unveiled a lightweight “monster” with exceptional power.

Yasa axial-flow electric motor: 550 kW from 13.1 kg

Weighing only 13.1 kg, it can produce 550 kW - equivalent to 748 hp (!). Yasa’s motor therefore sets new benchmarks for power density, delivering 42 kW (57 hp) per kilogram.

That is almost three times the average for today’s electric motors. To put this motor’s extraordinary power density into perspective, compare it with an internal-combustion engine: the G16E-GTS, the three-cylinder unit used in the Toyota GR Corolla, has a dry weight of 110 kg and develops up to 304 hp, or just 2.76 hp/kg.

Yasa’s “secret” lies in axial-flow technology, which differs from the radial-flow layout used by more conventional electric motors. This approach can dramatically reduce the size and weight of the entire unit while retaining - and exceeding - the power levels normally associated with larger, heavier motors.

For now, this 13.1 kg “monster” remains a prototype. Yasa says the most remarkable aspect of the motor is that it does not use exotic materials or technologies such as additive manufacturing (3D printing), which should make the transition to production easier.

As is already the case today, however, the most likely applications for this axial-flow electric motor will be supercars and luxury cars, owing to cost and production-scale considerations.

Axial-flow motors are already changing the electrification landscape

As mentioned, Yasa already equips road-going models including the Koenigsegg Regera, Ferrari SF90 and 296 GTB, along with the latest Lamborghini Revuelto and Temerario. The new 1360 hp AMG GT XX concept also uses this solution, not least because Mercedes-Benz acquired Yasa in 2021.

Yasa highlights the ability to integrate its axial-flow electric motors into transmissions while retaining low weight and performance.

Compact packaging for hybrid and electric cars

In practical terms, the compact dimensions of axial-flow electric motors could reshape the packaging of hybrid and electric cars.