Interfacial Engineering with Liquid Metal for Si-Based Hybrid Electrodes in Lithium-Ion Batteries

Abstract

Silicon (Si) anodes suffer from severe structural instability caused by volume expansion during lithium insertion and extraction. The extensive stress generated causes delamination at the anode/current collector interface and early capacity decay. We developed a novel anode structure by introducing a liquid metal layer in between Si and the Cu current collector. Both experiments and the density functional theory (DFT) simulation indicate an increased flexibility in the hybrid structure. No visible cracking or interface delamination was observed, attributed to the self-healing effect from the liquid metal. This work introduces a novel design for hybrid anodes with balanced mechanical strength and electrochemical performance.