Lithium metal anodes: Present and future

Commercial lithium-ion (Li-ion) batteries based on graphite anodes are meeting their bottlenecks that are limited energy densities. In order to satisfy the large market demands of smaller and lighter rechargeable batteries, high-capacity metallic Li replacing low-specific-capacity graphite enables the higher energy density in next-generation rechargeable Li metal batteries (LMBs). However, Li metal anode has been suffering from dendritic problems, interfacial side reactions, volume change and low Coulombic efficiency. Therefore, performance enhancements of Li metal anodes are rather important to realize the high energy density characteristic of metallic Li. In this review, the annoying Li dendrite growth, unstable reaction interface and practical application issues of Li metal anodes are summarized and detailedly discussed to understand the current challenges concerning Li metal anodes. For overcoming such remaining challenges, the corresponding strategies and recent advances are covered and categorized. Finally, we discuss future opportunities and perspectives for developing high-performance Li metal anodes.