Recent advances of anode protection in solid-state lithium metal batteries

Solid-state lithium metal batteries (SSLMBs) are considered promising candidates for next-generation energy storage devices due to their superior energy density and excellent safety. However, recent studies have shown that lithium (Li) dendrites in SSLMBs still exhibits a terrible growth ability, which makes the development of SSLMBs have to face the challenges posed by the Li dendrite problem. In this review, based on the analysis of the reasons for the formation of Li dendrites when the Li metal anode is matched with solid-state electrolytes (SSEs), various strategies and latest progresses of inhibiting the growth of Li dendrites are emphatically reviewed. Firstly, the origin and growth mechanism of Li dendrites are described. In particular, different causes of dendrite growth of lithium in inorganic electrolytes and organic electrolytes are distinguished. Secondly, some strategies to suppress dendrite formation and growth of lithium are discussed in detail based on the improved operation of the SSEs themselves, the insertion of interlayers, and the optimized design of Li metal anodes. Finally, the researches and development trend of Li anode protection in SSLMBs is prospected. This review intends to provide timely and important guidance for the development of anode protection in SSLMBs.