Stress Evolution Prediction for Silicon Anode Particle during Charging/Discharging and a Comparison with In-Situ Test Results

To unleash the potential of high-capacity Si-based anode in lithium-ion battery application, stress evolution and volume expansion mitigation within Si particles is of utmost importance in overcoming early degradation and side reactions caused by pulverization. An extensive and critical overview of the volumetric expansion, elastic, elastic-plastic behaviors of lithiated silicon at different concentrations is carried out by reviewing experimental and simulation studies available thus far. We summarized for the first time a quantitative characterization of these properties that are generally reached by researchers through looking into these research progress as a whole. A coupled diffusion-mechanical model is then proposed to simulate the silicon lithiation process by incorporating concentration-dependent volumetric change and elastic-plastic properties. The stress state within a Si anode particle is studied when a charging and discharging profile is applied. It is found that the stress evolution throughout the lithiation and de-lithiation process is in good agreement with in-situ experimental measurements reported. Furthermore, the current modeling methodology has the potential to be applied to Si-C related anode composites for microstructure evaluation and design optimization.