Molten salt electrochemistry is the branch of electrochemistry concerned with electrode and interfacial processes that occur in ionic media consisting of molten inorganic salts—alkali halides, cryolite, chlorides, fluorides, or oxide-containing melts—at elevated temperatures typically ranging from several hundred to above one thousand degrees Celsius ^[1]. Because the solvent is itself an ionic liquid, the electrolyte possesses exceptionally high electrical conductivity, a wide electrochemical window, and the ability to dissolve stable oxides, sulfides, and refractory compounds that are inaccessible to aqueous electrochemistry. At the working electrode, dissolved metal cations or oxygen anions undergo reduction or oxidation under an applied potential, so that the field embraces electrowinning, electrorefining, electroplating, and the direct electrolytic reduction of solid oxide feedstocks to metal ^[2]. The reactions are governed by the thermodynamics of the melt, the speciation and activity of dissolved ions, mass transport through the viscous salt, and the nature of the electrode–melt interface. The field therefore forms the electrochemical foundation of the Hall–Héroult aluminum process and of high-temperature metal extraction, recycling, and materials synthesis in which the molten salt serves simultaneously as electrolyte, reactant, and reaction medium ^[3].