Nanostructured immiscible Sb-Si@C composite Anodes: Advancing cycling stability for Lithium-Ion batteries

Abstract

Antimony (Sb) and silicon (Si) are promising anode materials for lithium-ion batteries, offering high theoretical capacities. However, Si’s poor conductivity, slow lithium-ion diffusion, and large volume expansion limit its performance. This study introduces a nanostructured immiscible Sb/Si@C composite fabricated via a simple mechanical ball-milling method. The Sb and Si particles are uniformly dispersed within a graphite matrix, where Sb enhances conductivity and the carbon matrix buffers volume changes during lithiation and delithiation. The composite material shows a high specific capacity of 949.3 mAh/g at 0.5 A/g and retains 763.2 mAh/g after 100 cycles, with a capacity retention of 80.4 %. This Sb/Si@C composite demonstrates strong potential as an anode material for lithium-ion batteries, combining high energy density and excellent cycling stability.