The automotive supplier Mahle has developed the most enduring e-motor currently available. The traction motor, which is unique on the market, can operate at high power for an unlimited period of time. This technological leap is made possible by a new cooling concept.
The new electric motor is particularly small, light and efficient and can be built to customer specifications without the use of rare earths. The new development is suitable for passenger cars, commercial vehicles as well as construction machinery and tractors. With the SCT-E motor, Mahle becomes a full-range supplier in the field of electric drives and covers all requirements from e-scooters to heavy commercial vehicles, off-road and industrial applications. The innovation will be presented for the first time at the IAA Transportation in Hanover in September 2022.
»Building large electric motors that deliver high performance in the short term is easy. What has been missing on the market so far to make e-vehicles fully suitable for everyday use have been drives that are both enduring and compact,« emphasizes Martin Berger, Head of Group Research and Advance Engineering at Mahle. »Our new SCT-E motor is the solution.«
On the engine side, Mahle is convinced that this paves the way for the replacement of the combustion engine in all vehicle classes. As recently as 2021, the automotive supplier presented a wear-free and scalable traction engine for passenger cars that operates very efficiently over a wide speed range.
The SCT-E engine, on the other hand, is designed to be particularly efficient within a specific speed range. Its continuous output is over 90 percent of its peak output - despite its very compact and lightweight design - as recent measurement results show. This represents a technological leap forward and allows it to be used in e-vehicles of all kinds, even under demanding conditions. Classic examples include driving an e-truck over mountain passes or repeated sprints by a battery-electric passenger car. These scenarios are only inadequately covered by the e-motors available on the market to date.
This load capacity is achieved in the new SCT-E motor through the use of an innovative integrated oil cooling system, which not only makes it robust, but at the same time enables the waste heat generated to be used in the overall vehicle system. The particularly compact design also results in material cost and weight benefits - a lighter engine requires less material in production and at the same time increases the possible payload in commercial vehicles.
When designing the product, Mahle opted for a so-called permanently excited motor, as this type of construction allows for a very compact design and no energy has to be transferred to the rotor as excitation current. This makes the motor efficient and wear-free. Neodymium magnets, currently the strongest permanent magnets that can be produced, are used to generate the magnetic field in the motor.
However, for greater independence from raw material prices and geopolitical developments, the SCT-E motor can also be designed without magnets. In the magnet-free variant, it would also operate wear-free and efficiently thanks to the contactless transformer developed by Mahle, while taking up only slightly more installation space.