Piezoelectric Field-Derived Mechano-Electrochemical Regulation for Durable SiO Anode.

Abstract

Silicon monoxide (SiO) has emerged as a promising high-capacity anode material for next-generation lithium-ion batteries. Nevertheless, the practical application of SiO anodes remains hindered by sluggish Li⁺ ion transport kinetics and persistent mechanical stress heterogeneity during deep lithiation. Here, we propose a piezoelectric functional-modification strategy that transforms the intrinsic expansion stress of SiO into a self-adaptive driving force for electrochemical regulation. By decorating SiO with piezoelectric LiTaO₃ (SiO-P), the periodic volume fluctuation during cycling activates localized electric fields that accelerate Li⁺ ion migration, homogenize interfacial charge distribution, and promote the formation of a uniform, robust SEI. The resulting SiO-P composite delivers exceptional cycling stability, maintaining 380.8 mAh g^-1 after 500 cycles at 2 C, with significantly enhanced durability validated in pouch-cell configurations. This work establishes a mechano-electrochemical paradigm that converts detrimental mechanical stress into a beneficial regulatory signal, offering a promising route toward high-energy, durable SiO-based anodes for practical LIBs.