Interface Issues and Optimization Strategies for Non‐Lithium‐Metal Anodes in All‐Solid‐State Batteries

Unraveling the interface issues of non-lithium metal anodes (NLMAs) in all-solid-state batteries (ASSBs) and devising effective regulation strategies to enhance the rate and cycling performance has become a prominent research focus in both academia and industry. As promising anode candidates for high-energy-density ASSBs, NLMAs, including silicon-based, graphite-based, and tin-based anodes, offer unique advantages in terms of abundant natural resources, low cost, and superior safety. In recent years, significant progress has been made in addressing the interfacial issues of NLMAs in ASSBs. However, comprehensive reviews focusing on the interfacial challenges and corresponding optimization advances remain very rare. In response, this review first elucidates the intrinsic differences between solid-solid interfaces in ASSBs and traditional liquid-solid interfaces, thereby clarifying the typical characteristics of ideal interfaces for high-performance ASSBs. Subsequently, we systematically summarize various interface issues and the underlying failure mechanisms of NLMAs in practical applications, followed by a comprehensive overview of state-of-the-art interface optimization strategies and their working principles. Finally, the critical challenges of NLMA interface optimization are highlighted, and future research directions are prospected. This review provides in-depth insights into the failure mechanisms and optimization strategies of next-generation NLMAs and offers valuable resources for beginners in the field of ASSBs.