Anchoring solvent to modify Li^+ solvation in Fe_2O_3 suspension electrolyte for lithium metal batteries

Abstract

To commercialize high-energy density lithium metal batteries (LMBs), addressing issues such as Li dendrite growth and electrolyte decomposition at Li metal (Li0)/ electrolyte interface are crucial. While research predominantly focuses on forming a stable solid-electrolyte interface (SEI) and suppressing the uneven growth of Li by electrolyte engineering, practical solutions for Li corrosion and electrolyte decomposition remain insufficient. Here we propose a system dispersing Fe2O3 nanoparticles (NPs) in a high-concentration electrolyte. This system, facilitated by strong interactions between Fe2O3 NPs and solvent molecules, alters the Li+ solvation structure. Modified Li+ solvation environment creates an environment conducive to stable SEI formation and uniform Li plating at the interface. Consequently, with reduced electron tunneling to the electrolyte at a stable surface of Li0 anode, electrolyte decomposition is mitigated, experimentally demonstrating an approximately twofold increase in the cycle life of anode-free LMBs. This research offers a fresh approach to the development of high energy density LMBs.