CFD Modeling of Gas Formation and Venting During the EV’s Battery Cells Manufacturing Process

The battery is a critical component of electric vehicles (EVs), where high power demands pose significant operational challenges. One such challenge is gas generation within the porous anode layer, which can lead to pressure buildup inside the battery. The complex interfacial dynamics at the microscale play a crucial role in determining the effectiveness of gas venting and the resulting pressure evolution. This study examines the effect of gas generation at two different length scales on the pressure rise and bubble dynamics. First, gas generation within a representative anode microstructure sample is investigated using a Volume of Fluid (VOF) framework that resolves tortuous flow passages. The simulations reveal that gas generation in such microstructures can lead to pressure rises of several thousand Pascals, with interfacial behavior primarily governed by surface tension effects. Second, a high-level single-cell simulation is performed using a porous media approach to evaluate system-scale gas venting and localized pressurization. This multiscale modeling framework provides key insights into the relationship between microscale gas dynamics and overall gas accumulations in the cell.