Tailored Silver Nanowires for Amplified Lithium-Ion Battery Performance and Inhibition of Lithium Dendrites in Silicon-Graphite-Silver Nanowire Composite Electrodes

In Li ion batteries using Si-based anodes, silver nanowires (AgNWs) are centrifugally mixed to prevent the loss of an electron conduction path due to the expansion of Si. In this study, a robust conductive network is created by modifying AgNWs to a width of 50 nm and length of 25 mu m, considering the constituents of the electrode microstructure and adjusting the concentration of polyvinylpyrolidine used as a binder. The variations in the electrode microstructure and the effect of AgNWs on Li behavior are examined. Distinct phase transformations and thermodynamically stable phases are estimated using density functional theory calculations based on a Li-Si-Ag ternary system. The incorporation of the AgNWs network into Si anodes offers multiple benefits including ultrafast electron transport, reduced charge and capacitance resistance, improved adhesion to the current collector, and suppressed Li dendrite formation. It enhances the specific capacity (15-18%) and adhesion force (86%). In particular, the 50 nm Si@Gr/C/AgNWs electrode exhibits the best performance (similar to 460 mAh g(-1)) and capacity retention characteristics (96%) at a current density of 0.1 A g(-1), with enhanced rate capability and charge efficiency, particularly at 1.6 A g(-1). The proposed AgNWs network will benefit high-performance and stable Si-based electrodes for advanced energy storage systems.