Biopolymer-blended protective layer for use in stabilizing the zinc anode in metal battery applications

Abstract

Metallic Zn anodes have recently attracted attention for use in large-scale energy storage systems; however, controlling the nucleation and growth behaviors of Zn is essential owing to its poor reversibility. In this study, we employed a protective layer (denoted XPpl) fabricated using xanthan gum and poly(ethylene oxide) (PEO). This layer exhibited a structured surface morphology and abundant oxygen-containing functional groups. When only glass fiber membrane (denoted GF) was used, Zn metal anodes polluted with dendritic Zn and broken fibers were observed after cycling. Upon introducing XPpl, dendrite-free Zn deposition was observed, and Zn metal was physically/chemically protected from the GF. An XPpl-protected ZnǁCu cell could undergo long-term operation for >5000 cycles at 2 mA cm−2. This study will provide insights into critical factors that affect Zn nucleation and growth, enabling accurate factor selection.