The Polymer Society of Korea

Abstract

Ga-based liquid metals (LMs) are promising interfacial materials for lithium metal batteries due to their conductivity, softness, self-healing, and low toxicity. They promote uniform, lithiophilic Li deposition and extend battery life. However, Ga’s high reactivity with metal current collectors can cause alloying, corrosion, and interfacial degradation. In eutectic alloys like GaIn and GaInSn, metal segregation further destabilizes the interface. Despite these issues, LM-induced corrosion has been largely overlooked. This study investigates the structural, chemical, and electrochemical impacts of Ga-based LMs on anode current collectors. We reveal that such corrosion critically shortens battery lifespan. These findings expose a key challenge in using Ga-based LMs and suggest design strategies for stable, durable interfaces in next-generation lithium metal batteries.