Self‐Limiting Partial Lithiation Induced by Interfacial Heavy Doping Boosts Li‐Storage Performance in Holey Silicon Nanosheets

Abstract Partial lithiation has emerged as a promising strategy to mitigate the volume expansion in silicon anodes. However, current implementations predominantly rely on externally imposed constraint approaches and inevitably sacrifice substantial capacity. Herein, an innovative self‐limiting partial lithiation strategy driven by interfacial heavy doping is proposed. Through ice‐templated self‐assembly of sol particles, the localized high‐concentration P‐doping is achieved at interconnected particle interfaces in 2D holey Si nanosheets. This interfacial heavy doping triggers a “region‐selective lithium shielding” effect, enabling in situ passivation and sustained retention of trace crystalline silicon domains during cycling. These retained crystalline domains, with dual characteristics of electrochemical inertness and self‐buffering mechanism, effectively mitigate the volume expansion of silicon anodes while causing only minimal capacity loss. Thanks to the partial lithiation behavior in holey self‐assembled nanosheets, the P‐doped silicon anode demonstrates remarkable cycling stability (2176.2 mAh g −1 after 200 cycles at 0.5 A g −1 ). Although P‐doping locally impedes Li + transport in heavily doped regions, it significantly promotes lithium‐ion kinetics in P‐poor/P‐free domains. Coupled with the improved electron conductivity, this synergy effect leads to superior rate capability (1590 mAh g −1 at 2 A g −1 ).