KETI, integration of electrode material and fiber material
Development of a novel Sn@Ni fiber electrode structure
Improving the structural stability of flexible batteries


As the IoT and wearable device markets grow, the demand for flexible batteries that perform stably even under conditions of mechanical deformation is increasing.

The Electronics and Telecommunications Technology Institute (KETI) announced on the 3rd that it has developed a new electrode structure that integrates electrode materials and fiber materials.

Existing flexible secondary battery electrodes have been studied primarily through technologies that change ‘metal foil’, which is vulnerable to mechanical deformation, to ‘carbon-based substrates’ or ‘polymer fabrics’ coated with conductive materials.

For carbon-based substrates, complex manufacturing processes and high costs are obstacles to commercialization, and for polymer fabrics, there are limitations in that cracks occur when mechanically deformed, electrode components are easily separated, and the capacity is low.

The Sn@Ni fiber electrode, developed by the team of Director Yoo Ji-sang and Dr. Woo Sang-gil of the Next-Generation Battery Research Center at KETI, together with the team of Professor Kim Jae-heon of Kookmin University and the team of Professor Lee Sang-young of UNIST, secured structural stability against mechanical deformation by integrating a layer of nickel (Ni), a conductive metal, with PET polymer fabric.

By applying the galvanic replacement method, some of the nickel can be used to store lithium.The principle is to have a higher energy density than existing ones by replacing it with capable tin (Sn).

The joint research team said that this Sn@Ni fiber electrode “has excellent mechanical durability, maintaining more than 96% of its capacity even after being bent 2,000 times to half the size of the battery,” and “its electrical conductivity has improved 600 times compared to existing electrodes.”

KETI is conducting follow-up research on a flexible secondary battery based on a polymer electrolyte with Sn@Ni fiber electrodes. Dr. Woo Sang-gil predicted, “In the future, a secondary battery system that combines these element technologies will contribute to the early commercialization of flexible secondary batteries and the advent of the next-generation wearable market.”

Meanwhile, this technology was selected as the cover paper for the April issue of 'Advanced Functional Materials,' which ranks in the top 10% of international academic journals in the field of materials science.