Silicon‐Carbon Spatial Distribution in Coral‐Like Architectures for Stress Alleviation and Stable Lithium Storage

ABSTRACT Silicon is a highly promising anode material for next‐generation lithium‐ion batteries due to its ultrahigh theoretical capacity, yet its severe volume variation and poor intrinsic conductivity hinder practical application. Here, a hierarchical macro‐mesoporous silicon‐carbon composite (e‐SiMP@C‐20) is developed via one‐step HCl etching of Al‐Si alloy followed by phenolic resin coating. The etched coral‐like silicon framework provides internal voids for volume expansion buffering, while the conformal carbon shell forms a conductive and elastic network, enhancing both electron and ion transport. As a result, e‐SiMP@C‐20 delivers a reversible capacity of 756.97 mAh g −1 after 500 cycles at 1 A g −1 , together with improved Li + diffusion. Finite element simulations confirm that a rational silicon‐carbon spatial distribution enables effective stress dispersion. This work provides a facile and scalable strategy for constructing micro‐sized porous silicon‐based anodes with high stability and fast reaction kinetics, offering insights for the commercial development of silicon‐carbon anodes in advanced lithium‐ion batteries.