Design Strategies for Electrolytes in Lithium Metal Batteries: Insights into Liquid and Solid-State Systems

Abstract

Lithium metal anodes are considered indispensable for next-generation high-energy batteries, but their practical application is severely hampered by interfacial instabilities that lead to uncontrolled dendrite growth and continuous electrolyte consumption. This review systematically addresses these challenges by evaluating state-of-the-art electrolyte engineering strategies for both liquid and solid-state systems. In liquid electrolytes, key approaches are analyzed, including high-concentration/localized formulations, fluorinated components, and functional additives designed to form robust and stable solid electrolyte interphases. For solid-state electrolytes, advances in polymer, inorganic, and composite systems are surveyed, aimed at enhancing ionic conductivity while mechanically suppressing dendrites. Finally,a forward-looking perspective is proposed, highlighting that the integration of multiscale simulation, machine learning, and data-driven screening will be key to the rational design and rapid discovery of advanced electrolytes. This integrated approach is expected to overcome a critical bottleneck, paving the way for the realization of safe and high-performance lithium metal batteries.