High-entropy interfacial engineering toward anode-free metal batteries

Anode-free metal batteries (AFMBs) are widely regarded as promising candidates for next-generation high-energy-density storage systems. However, their practical deployment is severely constrained by the poor reversibility of metal plating and stripping on anode-side current collectors, which arises from the absence of excess active metal sources. High-entropy materials, distinguished by their multicomponent composition, unique structural characteristics, and highly tunable physicochemical properties, provide a compelling framework for addressing the interfacial challenges inherent to AFMBs. In this review, we systematically summarize recent progress in high-entropy design strategies for constructing anode-side current collector interphases in AFMBs. Particular emphasis is placed on how high-entropy interphases reduce metal nucleation barriers by enhancing interfacial affinity, promote rapid and uniform ion transport through lattice distortion or amorphous structures, physically suppress dendritic growth via high mechanical robustness, and lower desolvation energy barriers by regulating solvation structures. Through these synergistic effects, high-entropy interphases enable highly reversible and stable metal deposition behavior under metal-deficient conditions. This review provides fundamental insights into the rational design of long-lifespan AFMBs through high-entropy-enabled interfacial chemistry and highlights future directions for advancing anode-free battery technologies.