A review of recent developments in the design of electrolytes and solid electrolyte interphase for lithium metal batteries

Abstract

Lithium metal batteries offer a promising solution for high density energy storage due to their high theoretical capacity and negative electrochemical potential. However, implementing of these batteries faces challenges related to electrolyte instability and the formation of a solid electrolyte interphase (SEI) on the lithium (Li) metal anode. The decomposition of liquid electrolytes leading to the creation of the SEI emphasizes the significance of the type of Li salt, solvent, and additives designed and used, as well as their interactions during the formation of the SEI. For practical applications, ensuring both the reversibility of the Li metal anode and electrolyte stability at high voltages is crucial. In this review, we explore recent advancements in addressing these challenges through new designs of electrolytes and SEI engineering practices. Specifically, we investigate the effects of electrolyte systems, including carbonate-based and ether-based solutions, along with modifications to these electrolyte systems aimed at achieving a more stable interface with the Li metal anode. Additionally, we discuss various artificial SEI structures based on organic and inorganic components. By critically examining recent research in these areas, this review provides valuable insights into current state-of-the-art strategies for enhancing the performance and safety of Li metal batteries.