BatteryFOAM: A comprehensive electrochemical-electrical-thermal solver with OpenFOAM for computational battery dynamics

This study presents a new development for the multi-physics simulation of lithium-ion batteries (LIBs), leveraging the open-source Computational Fluid Dynamics (CFD) software, OpenFOAM®. A new battery modelling framework, BatteryFOAM solver, is implemented based on the semi-empirical electrochemical sub-model proposed by Newman, Tiedemann, Gu, and Kim (NTGK). For the lumped-solid battery model, BatteryFOAM employs the finite-volume method with polyhedral mesh to predict the working voltage, transfer current, temperature, and heat release rate for LIBs under a constant discharge current rate (DCR). This solver incorporates three sub-models: (1) semi-empirical equations governing the open circuit voltage, electrochemical conductance, and polarization expressions for the transfer current in the electrochemical model; (2) the electrical model, which includes the potential Poisson-type equations, along with the application of Taylor expansion of boundary condition to address the ill-posed positive electrode potential partial equation; and (3) the thermal model including energy conservation equations considering the contributions from ohmic, electrochemical reversible, and polarization heat. To comprehensively verify and validate the solver accuracy and implementation, this study compares the results against the experimental, simulation and theoretical results. The results show that the battery working voltage is in good agreement with the experimental results at 0.3-6C and the relative error of transfer current density is <0.06% under 6C. By coupling the thermal model, both the simulation and experiment temperature of the battery center reach up to 320 K at 90% DOD and 3C. These demonstrate that BatteryFOAM reliably predicts LIB real-time characteristics at different DCRs. Besides, the BatteryFOAM can be further flexibly developed by coupling other models, such as side reactions and internal short circuit, based on this framework.