Atomic- and molecular-scale interfacial engineering for superior lithium metal anodes

Abstract Lithium metal anodes (LMAs) are among the most promising candidates for next-generation batteries with high energy density. However, their practical application is hindered by persistent challenges such as dendritic lithium growth, unstable solid electrolyte interphases (SEI), and poor Coulombic efficiency. Surface coating has emerged as a viable solution to address these limitations. In particular, atomic and molecular layer deposition (ALD/MLD) techniques offer unparalleled control over the fabrication of ultrathin, conformal coatings, making them especially suitable for stabilizing LMAs interfaces. This review comprehensively summarizes recent progress in applying ALD and MLD methodologies to construct durable artificial interphases on LMAs. We discuss the underlying mechanisms through which these coatings inhibit dendrite formation, improve interfacial integrity, and facilitate uniform lithium-ion transport. The roles of inorganic ALD coatings, organic MLD coatings, and their organic–inorganic hybrids are systematically examined, with a focus on their chemical composition, deposition behavior, and electrochemical characteristics. Moreover, we highlight the enhanced performance achieved through the integration of ALD/MLD-engineered interfaces in full-cell systems. The review concludes with a discussion of current challenges and potential research avenues aimed at advancing the rational development of effective LMAs protection strategies. Overall, this work offers valuable insights into the role of interfacial engineering via ALD and MLD in enabling the practical deployment of lithium metal batteries.