Magnetic Field Based Finite Element Method for Liquid Metal Batteries Modeling with Discontinuous Electric Potential Distributions
Résumé
In order to approximate magneto-static situations with discontinuous electric potential, we implement two finite element formulations, one based on the magnetic field and the other on the electrical scalar potential. Our interest in Liquid Metal Batteries (LMBs), a potential technology for storing intermittent renewable energy sources in large-scale energy storage devices, is what drives this effort. Three liquid layers make up an LMB: a lighter liquid metal on top (the negative electrode), a molten salt in the middle (the electrolyte), and a heavier liquid metal on the bottom (the positive electrode). These layers are immiscible and steadily stratified. Electrical potential variations, which can be represented as jumps at each electrode-electrolyte contact, are where energy is stored. The main goal of this work is to present novel finite element techniques for calculating potential and current distributions that take into consideration internal voltage jumps in liquid metal batteries. There are two alternative formulations that use the electrical potential and the magnetic field, respectively, as the primary unknowns. We address their uses for simulating the current distribution during the discharge phase in a liquid metal battery and validate them using different test cases.