Hyundai and Kia EVs to gain more space by moving components inside their wheels

Hyundai and Kia have designed a new way to package electric powertrain components in a car, resulting in future EVs having even more space than they do now.

The big idea is that the main drive system components will be moved to the spare space within the wheel hub – Hyundai calls this the 'Uni (Universal) Wheel' Drive System. This means that the platform of an EV will no longer have various electric powertrain components sitting on top of it; instead the platform will be almost completely flat, opening up new possibilities for space for passengers. Alternatively EVs could have larger batteries without the need for an increase in body size, or cars could be made smaller car without having to reduce the battery size.

The secret to this breakthrough is moving the EV’s reduction gear inside the wheel hub, with individual compact electric motors close to each wheel – meaning that these future EVs will be all-wheel drive, as well as having precise torque vectoring to boost dynamic ability and deliver high levels of driving stability.

Adding extra weight to a car’s wheels can cause problems with suspension systems and handling, but Hyundai says that this won’t be an issue. The Uni Wheel Drive System can be combined with electronic air suspension that can adjust ride height, and a wide range of suspension articulation will still be possible, so the new technology should have no impact on ride quality.

The company also says that there will be no loss to performance with the new technology, in fact the opposite is likely to be the case, because moving the reduction gear to the wheel hub results in significant torque output.

Apart from creating more space for occupants and/or luggage in a conventional car, the Uni Wheel Drive System offers particular benefits for self-driving cars; as they will have an almost completely flat floor, this will provide more creative possibilities when not having to design a car around a driver.