MAHLE Introduces New Range Extender Engine and Rare Earth-Free Electric Motor
System replaces about one-third of battery capacity with a compact diesel engine for heavy-duty electric trucks.
Automotive supplier MAHLE has unveiled a range extender system for heavy-duty electric trucks and a new rare earth-free electric motor, both designed to push truck electrification forward.
What Happened
MAHLE's range extender packages a combustion engine and generator into part of the space an electric truck's battery would normally occupy. The system is built to replace about one-third of the battery capacity of a typical electric truck with a compact diesel engine.
The assembly is self-contained: the generator, engine, thermal and fluid management, fuel tank, AdBlue tank, and exhaust treatment sit inside one box that drops into existing battery-electric platforms. The high-voltage generator features a newly developed oil cooling system, delivers 110 kW continuous and up to 130 kW peak power, and boasts a power density of more than 7 kW per kilogram. Its thermal management provides 48 kW of high-temperature and 15 kW of low-temperature cooling.
Swapping part of the battery for the range extender cuts the rear axle load by about 400 kg and total vehicle weight by about 600 kg, according to MAHLE.
Separately, MAHLE developed a new Contactless Transmitter (MCT) electric motor for heavy commercial vehicle drive axles. It uses no permanent magnets and therefore no rare earth elements, which the company says saves up to 3 kg of rare earth magnets per vehicle compared with a benchmark permanent magnet synchronous motor.
The MCT motor is 10% lighter and more efficient than a permanently excited design under real driving conditions, MAHLE said. It delivers peak output of 370 kW and torque over 900 Nm at 3,900 rpm, reaching about 95% efficiency in the EU's VECTO simulation cycle.
"Our range extender is the key to disconnecting the market ramp-up of battery-electric trucks from the inadequate pace of infrastructure development," said Marco Warth, MAHLE's Vice President of Corporate Research and Advanced Engineering.
Why It Matters
The range extender directly addresses one of the biggest hurdles for heavy-duty truck electrification: charging infrastructure that has not kept pace with vehicle deployment. By allowing battery-electric platforms to run on a smaller pack plus a diesel generator, fleets can operate longer routes without relying solely on public charging availability.
The rare earth-free motor reduces dependence on a supply chain concentrated in specific regions and could lower material costs while trimming vehicle weight — factors that matter for commercial operators watching total cost of ownership.
The Bottom Line
MAHLE's new range extender and contactless transmitter motor give truck makers options to balance battery capacity, weight, and infrastructure constraints as heavy-duty electrification scales up.
