Chinese Researchers Develop New Copper Foil

Shenyang (ANTARA) - Chinese researchers have developed a new type of copper foil that overcomes longstanding challenges in balancing strength, electrical conductivity, and thermal stability, offering a promising material for advanced electronics and next-generation energy storage systems. The innovative copper foil was created by a team led by Lu Lei at the Institute of Metal Research, which is affiliated with the Chinese Academy of Sciences (CAS), and was published in the journal Science on Friday (17/4). Copper foil is a key component in integrated circuits (ICs) and lithium-ion batteries. However, pure copper is soft and lacks strength, making it unsuitable for applications requiring high load-bearing capacity or heat resistance. Adding other elements can enhance strength and thermal stability, but this often reduces electrical conductivity. The breakthrough lies in a new microstructure design called gradient nano-domain architecture. Using an industrially scalable electrodeposition process, the team added a small amount of organic additives to produce a 10-micrometre-thick copper foil containing high-density super-nano domains, each approximately three nanometres in size. These small copper domains act like rivets embedded within the copper. They inhibit the movement of copper grains, thereby increasing strength and thermal stability while maintaining high copper purity. As a result, the material does not impede electron flow and retains good conductivity. The new copper foil achieves a tensile strength of around 900 megapascals, far exceeding that of conventional copper foils. Its electrical conductivity reaches 90 per cent of pure copper, about three times higher than other copper alloys with similar strength levels. The material also demonstrates exceptional thermal stability. The research team added that this study provides a new design pathway for developing high-performance metal materials. More importantly, the gradient nano-domain copper foil can already be produced sustainably on an industrial scale, supporting various advanced applications in electronics and new energy fields.