The Polymer Society of Korea

Abstract

To achieve high energy density in lithium-ion batteries, the development of silicon-carbon composites that surpass the theoretical limits of conventional graphite anodes is essential.  In this study, a buffer structure was designed using porous activated carbon derived from unutilized domestic petroleum residue to effectively control silicon's volume expansion. Specifically, a nano-sized silicon layer was formed on the petroleum-based porous activated carbon via Chemical Vapor Deposition (CVD), followed by a final exterior coating with pitch. In this buffer structure, the nano-silicon mitigates its own expansion stress compared to micro-particles, the abundant internal pores of the activated carbon physically accommodate silicon's volume changes, and the outer pitch-derived carbon layer provides additional cushioning to suppress the structural collapse of the electrode.