Nio EV motor wins prestigious engineering

CHINESE electric vehicle manufacturer Nio has received one of its domestic automotive industry’s highest engineering honours for a high-voltage electric drive system capable of delivering exceptional power density while doubling as a voltage booster for DC fast charging.

The company’s 925V electric drive technology received first prize in the Science and Technology Progress category at the recent 2026 China Society of Automotive Engineers (China-SAE) Science and Technology Awards.

Developed in collaboration with Tongji University, Harbin University of Science and Technology and Baoshan Iron & Steel, the system combines a new continuous-wave copper winding design with advanced thermal management and integrated charging functionality.

The technology achieves a claimed motor power density of 19.06kW per kilogram, controller power density of 226.92kW per litre and peak voltage-boosted charging output of 202.78kW.

Importantly, the project is not merely a laboratory exercise, with the technology entering mass production and subsequently finding its way into several Nio and Onvo production vehicles.

The development could also have implications for the Australian market, where Nio has signalled plans to introduce its namesake premium brand alongside the more affordable Onvo and Firefly marques.

Although local launch timing remains unconfirmed, the Firefly electric hatchback has already received Australian Design Rule approval and undergone local testing.

At the centre of the new electric drive system is Nio’s W-Pin continuous-wave winding technology, which replaces the conventional arrangement of multiple individual copper conductors joined by welding.

Instead, the company uses continuous rectangular copper conductors, precisely shaped and positioned within the motor’s stator to improve copper packing density and reduce the number of electrical connections.

The manufacturing process employs 12 copper conductors, each measuring approximately five metres long, which are formed through 24 precision bends.

According to technical reports, the development team overcame significant manufacturing challenges associated with bending the relatively rigid conductors without stretching or damaging their insulation.

A revised planar forming process eventually enabled the company to control insulation thickness to just 0.14mm and maintain motor assembly tolerances within 0.02mm.

The result is a more compact motor design that Nio says can deliver greater power density while improving thermal management and reducing manufacturing complexity associated with conventional welded windings.

The 925V electrical architecture also presents additional engineering challenges, particularly concerning insulation durability and the demands of operating at high voltage.

To address these concerns, the development team created new insulation materials and subjected the system to extensive durability testing.

This included 1300 hours of continuous high-temperature operation without failure, more than 500 hours of simulated high-altitude testing at elevations equivalent to 5500 metres, and vibration testing at forces reaching 5.5g.

The system was also subjected to temperatures ranging from minus 40 to plus 85 degrees Celsius over a period exceeding two months.

However, perhaps the most interesting development is the ability to use existing electric drive components to boost incoming charging voltage.

Rather than relying on a separate high-power voltage conversion unit, Nio’s system uses the electric motor windings and associated inverter electronics to increase voltage supplied by lower-voltage DC charging infrastructure.

When the vehicle is stationary and charging, the motor windings effectively become part of the voltage conversion circuit, enabling the higher-voltage battery to accept energy from charging equipment operating at a lower voltage.

The arrangement has demonstrated peak voltage-boosted charging power of 202.78kW, potentially reducing the need for additional conversion hardware, saving weight and freeing up valuable packaging space.

The figure relates specifically to voltage-boosted charging, however, and should not be confused with the vehicle’s maximum charging capability when connected to a suitably powerful high-voltage charger.

For example, Nio’s flagship ET9 features a 900V-class electrical architecture, with a maximum system voltage of 925V and a claimed peak DC charging capability of 600kW.

Actual charging performance remains dependent on the output of the charging equipment, battery conditions and vehicle operating parameters.

The principle of using motor and inverter components for voltage conversion is not entirely new.

Hyundai’s Electric Global Modular Platform (E-GMP), used in Australian-delivered models including the Ioniq 5, already employs its traction motor and inverter to support charging from both 400V and 800V infrastructure without requiring a separate voltage booster.

Nio’s achievement lies in combining this functionality with its high-power-density motor architecture and developing a manufacturing process suitable for large-scale production.

The technology is already used in models including the Nio ET9, ES8, and ES9, together with the Onvo L80 and L90.

Nio says its electric drive research programme, which commenced in 2015, has resulted in 146 authorised patents and contributions to six Chinese national automotive standards.

While there is no confirmation that the award-winning system will feature in vehicles sold in Australia, its development demonstrates the pace at which Chinese manufacturers are advancing electric propulsion technology.

For Australian EV buyers, the potential benefits are straightforward – smaller and lighter drive systems, more efficient packaging, and improved compatibility with existing charging infrastructure.

And with electric vehicles increasingly adopting higher-voltage electrical architectures, technology that reduces the cost and complexity of accommodating lower-voltage charging equipment is likely to become increasingly important.