From Design to Application: Interface Engineering in Hierarchical Si/C Anodes for High‐Energy‐Density Batteries

Silicon anodes, renowned for their ultrahigh theoretical capacity, are pivotal for advancing next-generation lithium-ion and solid-state batteries. However, their severe volume variation during cycling poses a fundamental challenge, leading to rapid electrochemical failure. This review systematically elucidates intrinsic mechanisms and design strategies for high-performance silicon/carbon (Si/C) anodes via multi-scale interface modulation, focusing on chemical vapor deposition (CVD)-derived composites as a key model system. We explore the control of internal Si/C and electrode/electrolyte interfaces, while discussing complementary strategies such as intrinsic optimization (doping, alloying), architectural engineering (porous, yolk-shell structures), and electrode-level regulation (binders, electrolytes). The discussion extends to pouch cells and solid-state batteries, where interface stability is paramount. By establishing structure-interface-performance correlations, this work provides a holistic framework for transitioning high-capacity silicon anodes from laboratory prototypes to commercial applications.