Author: Shweta Dhillon
Title: Modelling Capacity Fade in Silicon Graphite Composite Electrodes
Affiliation: Uppsala University
Silicon based anodes are highly promising candidates for Li-ion batteries, with energy densities on the cell level beyond 350 Wh/kg . Volume expansion and continuous side reactions at the silicon/electrolyte interface are, however, major obstacles that are hampering their commercialization. Current state-of-the-art anodes can present composites of graphite and Si, but with limited Si contents. We here present an electrochemical simulations based on finite element methodology to better understand the degradation mechanisms in silicon-graphite composite anodes. A 1D battery model including SEI layer growth and parasitic reactions are constructed for porous Si/graphite composite electrodes in half-cells. By simulated electrochemical impedance spectroscopy responses during charge and discharge cycles, insights into morphological changes are obtained. These computational results are supported by experimental investigations.