Silicon (Si) has the highest specific capacity (4200 mAhg^-1) and volumetric capacity (9786 mAh cm^-3) among the material candidates, which makes it the most promising material for the Lithium Ion Battery (LIB). However, the drastic volume fluctuation (~400%) during the lithiation/delithiation process reduces the battery cyclability and affects the battery reversibility. To overcome these limitations, different architectures have been developed for incorporating Si to accommodate the volumetric changes within the conductive matrix.

The combination of electrospinning and electrospray processes has been used to fabricate three different hierarchical network architectures based on nanoscale Si and Polyacrylonitrile (PAN). Among these hierarchical architectures, the core-shell Si/PAN structure and the Si/PAN multilayer structure have significantly improved the cycling performance with high capacity and good capacity retention. Cyclization has also been performed to form the hierarchical conductive framework, which provides a continuous electron transport network and high porosity to address the volume expansion during electrochemical reactions. By integrating electrospray process in the synthesis process, a greatly improved capacity is achieved with a high reversible area capacity over 2mAh/cm². This work will present the results of our systematic investigation on structure-property relationships in the Si/PAN hierarchical architectures.