Back Cover: In article number BTE2.20220032, Wenbo Liu and co-workers develop a simple and effective strategy to achieve PANI-modified freestanding 3D dendritic hierarchical porous Cu-Sn nanocomposites, which shows ultrahigh areal capacity and good cycling stability as additive-free thick anodes for LIBs. The Sn content and areal capacity can be tuned easily by changing the dealloying time of initial alloy for 3D tin-based thick anodes with adjustable capacities toward high-performance LIBs.