Nanocrevass-Rich Carbon Fibers for Stable Lithium and Sodium Metal Anodes

Abstract

Electrodes based on lithium/sodium metal are promising anodes for high-energy-density batteries because of their high theoretical capacity and low reduction potential. However, both lithium and sodium suffer from dendritic growth and large volume changes during long-term cycling. In this paper, we develop a novel electrode system with enhanced wettability by introducing nanocrevasses into carbon fiber scaffolds. These nanocrevasses facilitate the penetration of molten metal, enhancing physical and chemical interactions between the alkali metal and the carbon scaffold. Thus, the carbon fiber acts as a host scaffold to store Li/Na metal. The resulting Li/C and Na/C composites exhibit stable long-term cycling over hundreds of cycles. This strategy can also be applied to fabricate electrodes for seawater batteries. The proposed approach is suitable for scalable production using recycled metal waste. Thus, the addition of nanocrevasses to carbon fiber as a scaffold for alkali metals can generate environmentally friendly and cost-effective composites for practical electrode applications.