Understanding the lithium dendrites growth in garnet-based solid-state lithium metal batteries

Garnet-based solid-state lithium (Li) metal batteries are regarded as one of the most promising high-energy-density and high-safety batteries because of the broad electrochemical stability window and high Li ion conductivity of garnet electrolytes, as well as their excellent chemical stability against Li metal. However, during the practical batteries cycling, it is found that Li dendrites grow in the interior of garnet, especially in the grain boundary, thus leading to the short circuit of the working batteries, which seriously hinders the application of garnet-based Li metal batteries. In this review, we summarize the Li dendrites growth mechanism, characterization techniques, and the interfacial issue of garnet-based solid-state Li metal batteries. Meanwhile, the strategies for regulating Li dendrites growth are also analyzed. In addition, the further perspective and some suggestions are proposed to develop garnet-based solid-state Li metal batteries. This review tends to show fresh views on the understanding of Li dendrites growth mechanism in garnet electrolytes and the rational design of interfacial layer for regulating dendrites and manufacturing the batteries when pairing with Li metal anode.