The Effect of Diffusion Induced Fatigue Stress on Capacity Loss in Nano Silicon Particle Electrodes during Cycling

Electrode materials are subjected to cyclic diffusion induced stress and fatigue damage during cycling, and this leads to their capacity loss inevitably. In our work, both theoretical study and experimental observation are built up to analyze the cyclic stress and capacity loss considering the influence of the charging rates and state of charging. It can be found by our theoretical model that the cyclic stress amplitude may be affected by these key parameters, which are increasing with the charging rates at given the state of charging. Moreover, the experimental data on the capacity loss during cycling are acquired when the nano silicon particles are considered as the electrode materials in the lithium ion battery. Finally, these results of the analytical method are compared with the experimental data on the capacity loss. The results have shown that the capacity loss per cycle is increasing with the increases of charging rates, and larger charging rate leads to greater stresses. The findings of this work have offered an insight on developing the high capacity electrode for lithium ion battery. (C) 2016 The Electrochemical Society. All rights reserved.