Dynamic response analysis of cylindrical lithium-ion battery under impact loadings: A theoretical study

The prediction of serious deformation for lithium-ion batteries (LIBs) under impact loadings becomes an important challenge for engineering application. In this paper, a theoretical model is developed to investigate the dynamic responses of cylindrical LIBs based on the membrane factor method. The cylindrical LIB is simplified as double-layer structure consisting of the casing and jellyroll. The plastic yield criterion is established by utilizing tensile yield strengths and the corresponding membrane factor fn is defined. The dynamic responses of the cell under radial impact loading are explored. The accuracy of this method is verified by the corresponding finite element (FE) results. In addition, a comprehensive quantitative analysis of the governing factors of fn is conducted under different boundary conditions. Using the theoretical model, the response characteristics of the cell under different initial velocities and masses are investigated. The approximate equation for the variation of the maximum deflection with initial velocity and the saturation impact time are presented. The tendency of the deformation changing with size and tensile properties of the cell is obtained. These researches will provide technical support for the failure prediction and structural safety design of cylindrical cells.