Molecular dynamics simulation of microstructure and thermophysical properties of LiCl–CaCl2 eutectic molten salt

Abstract Chloride molten salt systems are widely used as electrolytes for molten salt electrolysis because of their relatively low eutectic temperatures and good thermal stability, but there is a serious lack of data on the thermophysical properties of chloride molten salts at elevated temperatures, whereas the nature of the electrolyte is very important for the electrolysis process. In this paper, the variation of the microstructure and thermophysical properties of the binary mixed LiCl–CaCl2 molten salt system with temperature and composition is calculated using molecular dynamics (MD) simulations based on the BMH potential. The microscopic conformations observed in LiCl–CaCl2 molten salts are mainly irregular, distorted tetrahedra and octahedra, which dynamically coexist, as analyzed by the radial distribution function, coordination number and angular distribution function. In addition, the effects of temperature and composition on the density, ionic self-diffusion coefficient, shear viscosity, and ionic conductivity of the molten salts were investigated, and the relationships of the thermophysical properties of LiCl–CaCl2 molten salts with temperature and composition were obtained, which provide fundamental thermophysical data for the molten salt electrolytes.