Artificial interphase layers for Li metal anode, what’s next?

Lithium (Li) metal batteries (LMBs) are regarded as promising next-generation rechargeable batteries owing to the high theoretical specific capacity and the lowest potential of the Li metal anode (LMA). Nevertheless, the practical applications of LMA have been restricted by uncontrollable Li dendrite growth, enormous volume change and unstable interfaces between LMA and electrolyte. Among all the available strategies, the rational designs of artificial interphase layers (AILs) are the promising methods to solve these problems at the interfaces between LMA and electrolyte. In this review, we generally summarize the recent typical examples of in/ex-situ formed AILs for stabilizing LMA/electrolyte interfaces. Particular considerations have been taken on the components and structure characterizations in the design principle of AILs for suppressing uncontrollable Li dendrites growth, constructing stable interfaces and addressing the huge volume variation. Finally, the remaining challenges and the research direction for high performance AILs for safe and stable LMBs are provided.