Piezoelectricity-driven structural stabilization and electrochemical enhancement in silicon anodes: a novel force-electric coupling framework

This study presents a novel approach to enhance silicon anode performance through barium titanate (BTO) incorporation, with the establishment of a force-electric coupling model. By introducing piezoelectric BTO into silicon matrices, we successfully improved both the mechanical stability and electrochemical kinetics of the anode. The developed force-electric coupling model explains how BTO mitigates stress accumulation during lithiation while optimizing the kinetics of Li⁺ and electron transfer. Experimental verification and multiphysical simulation indicate that Si@BTO effectively eliminates structural degradation during the cycling process and significantly reduces the charge transfer resistance. The force-electric coupling mechanism further facilitates stable solid electrolyte interphase (SEI) formation. When paired with LiFePO₄ cathodes, Si@BTO maintains 76% capacity retention after 500 cycles at a 10 C rate. This work establishes a basic force-electric coupling model framework and offers insights into the development of advanced silicon anode batteries with exceptional performance.