Impact of External Magnetic Fields on the Electrochemical Performance of Liquid Metal Batteries: A Finite Element Analysis

The extended cycle life, excellent safety, and affordability of liquid metal batteries (LMBs) make them a viable option for large‐scale stationary energy storage. However, stable stratification in the positive electrode inhibits convective mixing and causes extreme concentration polarization, which limits their discharge performance. In this study, we employ the finite element method to investigate the influence of external magnetic fields on the charge and discharge behavior of three‐layer battery composed of Mg|LiF–LiBr|Te. Simulation results show that when a 120 mT magnetic field is applied, the discharge voltage rises by 24.43% at a current density of 300 mA cm ⁻² . Strong magnetic effects are observed at a higher current density of 700 mA cm ⁻² , where merely 80 mT magnetic field increases the discharge voltage by 62.66%. Additionally, we model and investigate three different LMB topologies with electrolyte thicknesses of 13 mm, 8 mm, and 5 mm. The voltage generated by the 5 mm‐thick electrolyte LMB is 0.24 V higher than that of the 13 mm‐thick electrolyte LMB by indicating that higher operating voltages are produced by thinner electrolytes. The findings enhance LMB performance and demonstrate that proper control of fluid flow is crucial for achieving better efficiency.