The Polymer Society of Korea

Abstract

The development of anode-free lithium metal batteries (AFLMBs) holds great potential for next-generation energy storage due to their high theoretical energy density and simplified design. Yet, the absence of a host anode leads to unstable lithium deposition and poor interfacial reversibility. To address these challenges, we introduce polyethylene oxide (PEO) coatings with varying molecular weights as artificial interfacial layers on copper current collectors. This study focuses on how molecular weight influences the structural and electrochemical properties of the PEO layer, including polymer morphology, lithium ion transport, and solid electrolyte interphase (SEI) formation. Through a systematic comparison, we reveal how tuning polymer chain length can optimize interface stability and cycling performance in AFLMB systems, offering key insights into the structure–performance relationship of polymer-modified interfaces.