Audi patents new electric vehicle range-extender technology

Audi has filed a patent for a new type of extended-range electric vehicle (EREV) powertrain that aims to optimize the use of electric motors. Unlike traditional EREVs where an internal combustion engine acts solely as a generator via a separate motor, Audi’s design integrates the combustion engine directly with a secondary electric motor using specialized couplings and a differential.

In this system, a primary electric motor drives one axle. When four-wheel drive is required, a secondary electric motor engages the other axle. However, when four-wheel drive is not needed, the secondary motor can be decoupled from the wheels and connected to the combustion engine to function as a generator, charging the battery.

This approach seeks to reduce manufacturing costs by eliminating the need for a dedicated third generator motor, though it introduces increased mechanical complexity through additional moving parts. The system’s ability to provide continuous all-wheel drive may be limited when the secondary motor is occupied with generating power. It remains uncertain if this technology will move into mass production.