Advancing Lithium Metal Batteries

Context & ScaleLithium (Li)-ion batteries have been widely used as power sources for portable electronic devices and are emerging into transportation and grid applications, but the energy density of the state-of-the-art Li-ion batteries will reach its theoretical limit soon, and new battery designs are urgently needed to satisfy the increasing demand for high-energy-density batteries. In this regard, Li metal anode material has attracted worldwide attention because of its many merits. Although practical applications of Li metal anodes are still limited by several challenges, such as dendrite growth and low coulombic efficiency, rapid development of new materials and electrode designs in recent years has overcome many bottlenecks in this field and hastened the practical applications of high-energy-density and high-performance rechargeable Li metal batteries. In this Perspective, recent significant progress on stabilization of Li metal anodes for Li metal batteries is highlighted. We also present a perspective on future directions and possibilities to better address the existing challenges of Li metal anodes and Li metal batteries.SummaryConsidering the limited energy density of traditional graphite-anode-based lithium (Li)-ion batteries, alternative high-capacity anodes are greatly needed for the next-generation high-energy-density battery systems. In this regard, Li metal is well known to be one of the most promising anodes due to its ultrahigh capacity (3,860 mAh g−1) and the very low standard negative electrochemical potential (−3.040 V). However, dendrite growth and high reactivity of Li metal anodes result in low cycling efficiency and severe safety concerns. The recent revival of research and development on Li metal anodes has brought new, in-depth understanding and key experimental progress toward Li metal protection and enhanced performance of Li metal batteries. In this Perspective, we concisely review recent discoveries in this field and suggest possible new research directions for further development of Li metal batteries.Graphical abstract