An integrated anode stress model for commercial LixC6-LiyMn2O4 battery during the cycling operation

An integrated stress model is developed to study the cycling effect on the commercial LixC6 electrode, which has bridged the stress/strain analysis with the battery internal multi-transport processes. A LixC6-LiyMn2O4 cell is utilized as a physical base, and the battery charging-discharging induced SEI film growth are included in the model development. The important factors including depth of discharge, charging-discharging rate, cooling conditions, end of battery charge voltage as well as the particle packing pattern are investigated in the cycling operation. Results show that both the thermal stress and the chemical stress increase with the battery cycling, and the maximum local stresses are present in the middle of the LixC6 particles and the interfaces. The potential of fracture can be raised by the elevated battery temperature and lithium concentration gradient. A denser packed LixC6 electrode can reduce the maximum local stress in the electrode particles, and can improve the stability of the electrode structure in the cycling by flattening the local stress/strain distribution.