Control Volume Free Element Method for Simulating Thermal Runaway of Lithium-Ion Battery

The safety of lithium-ion batteries is a critical concern, and this paper introduces a novel simulation approach for thermal runaway using the control volume free element method (CVFrEM). This method uniquely integrates the geometric adaptability of mesh-free techniques with the local conservation properties inherent to the finite volume method. The governing equations for heat generation and heat transfer within the battery are discretized through the CVFrEM framework, thereby ensuring strict energy conservation at the local control volume level. To accurately capture the nonlinear Arrhenius kinetics governing the internal reactions, a coupled solution algorithm is implemented within the CVFrEM formulation. The proposed method is rigorously validated against both experimental data and reference results, confirming its predictive accuracy and exceptional numerical stability, particularly in scenarios involving steep thermal gradients. Overall, this work offers a promising numerical tool for predicting thermal runaway events and provides valuable insights for advancing battery safety simulations.