Spanish researchers have developed a new material that could transform electric vehicles (EVs), drones, and aircraft by replacing copper wiring with lighter, stronger carbon nanotube fibers. Published in Science, the research from the Institute of Nanoscience and Materials of Aragon and the IMDEA Materials Institute focuses on a chemical doping process that increased nanotube conductivity by 17-fold without compromising structural integrity.
At ambient temperature, the doped fibers achieve approximately 40% of copper's electrical conductivity. However, on a weight-adjusted basis, their specific conductivity exceeds that of aluminum. The fibers weigh about one-sixth of copper while offering roughly five times the tensile strength. Earlier versions of these fibers were recognized for being tough and lightweight but lacked sufficient current-carrying capacity—a gap that this conductivity gain now addresses.
The key improvement came from treating the fibers with tetrachloroaluminate (AlCl4-), a compound that acts as a dopant. Introducing charge carriers without disrupting the atomic lattice had long been a core difficulty, and the researchers say this method overcomes that challenge. Preserving structural integrity was as important as the conductivity gain, since a conductor that fails in service has no practical value.
Modern EVs carry a significant copper load, especially in thick wiring bundles that manage high-voltage power. That mass adds up and reduces range. Switching to a lighter material reduces vehicle mass and extends range, while lower resistivity at operating temperatures cuts heat buildup. In drones, reducing cable mass translates directly into longer flight time. For aircraft developers, trimming weight at any point yields outsized returns.
The material also holds up reliably in dry conditions and shows acceptable moisture tolerance—properties that matter for transportation certification standards. On specific conductivity, the benchmark manufacturers prioritize most, the treated fibers have entered territory that warrants serious engineering attention. At peak values, they also exceed aluminum's conductivity on an absolute basis.
The remaining challenges involve manufacturing: producing consistent fibers at scale, ensuring hardware compatibility, and establishing a cost profile competitive with conventional metals. If those problems can be solved, the technology could move from laboratories into the electrical systems of next-generation EVs and aircraft. Recycling infrastructure for these materials will also need to be developed.
Many firms in the automotive space, such as Ferrari N.V. (NYSE: RACE), will be watching to see whether this new material becomes commercially available at scale and at price points that justify switching from copper.
