Understanding and Enhancing Silicon Nanoparticle Distribution during Electrode Processing

Abstract

Abstract Silicon-dominant anode is of great interest because of its potential to boost the cell-level energy of state-of-the-art Li-ion batteries. While silicon materials are extensively studied, the electrode level understanding, especially the coating process of Si particles, are not much investigated which plays an equally important role in unlocking the full potential of silicon anodes. Herein, the electrode processing of Si-dominated anode (52.8 wt.%, 3.5-4.5 mAh/cm2) is being investigated to understand the relationship of processing-morphology-properties of Si anode at electrode level. It has been found that almost-undetectable Si agglomerates easily form during electrode processing, which grow into big protrusions after lithiation and trigger potential internal shorting and self-discharge problems. A facile slurry filtration step is proposed to homogenize the particle distribution within Si-dominant electrode which improves the electrochemical performances and storage stability of Si-based Li ion batteries.