Research Trends in the Design Strategies of Anode Architectures for Anode-Free Lithium Metal Batteries

With the increasing demand for high-energy-density batteries, anode-free lithium metal batteries (AFLMBs) have attracted considerable attention as promising next-generation energy storage systems that can replace conventional lithium-ion and lithium metal batteries. Owing to their unique configuration, in which both the graphite anode active material and the lithium metal host are eliminated, AFLMBs can theoretically achieve very high energy density as well as improved thermal stability and operational safety. However, during the initial charging process, heterogeneous interfacial deposition occurring between the copper current collector and lithium induces a high nucleation overpotential, and during repeated lithium plating/stripping it causes dendrite growth, severe volume expansion, and irreversible loss of active lithium. These issues act as critical factors that degrade the cycle life and stability of AFLMBs, thereby limiting their practical application. To overcome these challenges, various anode architecture design strategies, including current collector modification and the introduction of artificial solid electrolyte interphases, have been proposed. In this review, recent research trends in anode architecture design strategies for the practical implementation of AFLMBs are comprehensively discussed.