Magnetron Sputtered Metallic Thin Films as Li‐Ion Battery Anodes

Metallic thin film anodes demonstrate attractive potentials for Li-ion batteries because of high-energy densities, safety, flexibility, light weight, etc. Sluggish Li-ion reaction kinetics, serious volume expansion, and low initial Coulombic efficiencies (ICE) are three barriers hindering their practical applications. In this review, advances of magnetron sputtering technology developed to solve these barriers are summarized and discussed. First, the basic Li-ion storage characteristics of elemental metals are discussed to demonstrate the merits of magnetron sputtering to fabricate metallic film anodes. Second, lithation/delithation behaviors of five typical metallic anodes (Si, Ge, Sn, Al, and Sb-based anodes) prepared by magnetron sputtering are sequentially summarized. Developed strategies, including nanostructure engineering, hybridizing, and alloying, are discussed in detail. Then, the importance of magnetron sputtering to fabricate all-solid-state thin-film and micro batteries with metallic thin-film anodes is further demonstrated. Finally, future perspectives for remaining challenges and corresponding strategies to develop magnetron sputtered metallic anodes and full batteries are discussed.