Scientists build the first electric motor without any metal

South Korean researchers successfully created the world’s first fully functional electric motor using only carbon nanotubes instead of traditional copper coils, marking an important step towards an ultra-lightweight transportation system.

The motor was made by the Korean Academy of Science and Technology (KIST) team and not only does not have metal components, but can actually power toy cars over half a meter per second. This achievement can greatly reduce weight by maintaining performance while greatly reducing weight, thus changing everything from electric cars to spacecraft.

The breakthrough focused on solving a decades-old problem: how to make carbon nanotubes clean and conductive replace real-world copper. The researchers used innovative purification processes inspired by liquid crystals to remove metal impurities that have long plagued nanotube technology, while retaining the tube’s characteristics.

Weight issues in electric transportation

Every gram is important in modern transportation. Whether it is expanding the range of electric vehicles, improving drone flight time, or reducing the launch cost of spacecraft, weight loss can be directly translated into energy saving and better performance.

Motor coils are traditionally used with copper because of their excellent conductivity. But the high density of copper (8.9 grams per cubic centimeter) makes it a heavyweight ingredient. The conductivity of carbon nanotubes is similar, with only 1.7 grams per cubic centimeter, which may reduce the weight of exercise by more than 80%.

The challenge has always been manufacturing. Carbon nanotubes are often contaminated by metal catalyst particles during production, which severely reduces their electrical properties and makes them unsuitable for high-performance applications such as electric motors.

Important research achievements:

• The first functional motor using 100% carbon nanotube coil
• Increased conductivity by 133% through new purification process
• Metal contamination decreased from 12.7% to less than 0.8%
• Specific performance almost matches copper-based motors

LCD cleaning revolution

The team’s solutions draw inspiration from an unexpected source: LCD, the technology behind LCD displays. They developed what is called the last (cleavage liquid crystal assisted surface texture) process that uses the unique properties of the “fourth state of matter” to clean carbon nanotubes at the molecular level.

“By developing a new concept of high-quality CNT technology that has never been seen before, we are able to maximize the electrical performance of the CNT coils to drive the motor without metal,” said Dr. Dae-Yoon Kim, who leads the research team Kist.

This process forms a liquid crystal state by dissolving the carbon nanotubes in chlorosulfonic acid, so that the tubes are naturally aligned in an ordered pattern. When the solution comes into contact with water, it produces hydrochloric acid, which etches out the iron catalyst particles when the nanotubes are intact.

What makes this approach unique is its accuracy. Previous cleaning methods often damage the nanotube itself, thus destroying its electrical properties. The last process selectively removes impurities, thus retaining the hexagonal carbon structure, giving the nanotube excellent conductivity.

Beyond News: Performance Details

Although the initial report focused on basic operation of the motor, the study revealed key performance indicators not highlighted in early coverage. The conductivity of purified carbon nanotube cables reached a conductivity of 7.7 megawood per meter, a substantial improvement that made them within a surprising distance for practical applications.

Perhaps more importantly, the researchers found that the specific rotation speed of its carbon nanotube motor (performance per unit weight) was only 1.06 times lower than that of copper-based motors. The proximity of weight-adjusting performance elements suggest that further improvements can make carbon nanotube motors even better than traditional designs.

The team showed extraordinary stability, with its motor maintaining continuous operation for at least 60 minutes at different power levels, maintaining consistent performance. This reliability solves the critical question of whether carbon nanotube-based systems can handle real-world operating conditions.

From the laboratory table to the track

The researchers did not stop the laboratory demonstration. They built a complete scale car powered by a metal-free electric motor and tested it on actual asphalt roads. The vehicle drove 10 meters in 25 seconds to reach the finish line, with a red sculpture with the letter “Kist”.

This real-world test reveals potential and current limitations of the technology. Although the carbon nanotube motor successfully powers the car, copper-based motors still achieve higher absolute performance, reaching speeds of 1.35 meters per second, while the nanotube version has a speed of 0.52 meters.

However, weight advantage tells a different story. The weight of carbon nanotubes is only 78.75 mg, while the weight of equivalent copper wire is 379.08 mg, which may be crucial for weight-sensitive applications.

Practical application approach

The application envisioned by the research team goes far beyond toy cars. “Based on innovations in CNT materials, we will lead the way in localized materials such as conductive materials for batteries, batteries and robotic cables for semiconductors,” said Dr. Dr. King explained.

The technology may be particularly valuable in aerospace applications where every gram saved can be converted into a large amount of fuel saving or increased payload capacity. Electric aircraft, drones and spacecraft can all benefit from lighter motor systems that maintain performance.

Electric vehicles represent another major opportunity. Although current technology has not yet met the absolute performance of copper, saving weight can expand the range of the vehicle and increase efficiency – a key factor in adopting electric vehicles.

What’s next?

The researchers acknowledge that carbon nanotube motors are not ready to replace copper in all applications. But their work provides a clear roadmap for improvement. Purification technology, nanotube structure optimization and further advances in manufacturing processes may narrow the remaining performance gap.

The team plans to explore different types of carbon nanotubes that have not been fully characterized, optimize insulation materials for better thermal management, and refine carbon nanotube components specifically.

Perhaps most interestingly, researchers believe that future electric vehicles and urban air mobility systems could be built entirely from electrical systems based on carbon nanotubes. Although this vision remains for several years, the first metal-free motor represents a crucial proof of concept.

For an industry increasingly focused on sustainability and efficiency, the ability to build functional motors without traditional metals can glimpse a more relaxed, more sustainable future where the materials themselves will promote solutions rather than problems.

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