Application of Liquid Metal Electrodes in Electrochemical Energy Storage

Lithium metal is considered to be the most ideal anode because of its highest energy density, but conventional lithium metal-liquid electrolyte battery systems suffer from low Coulombic efficiency, repetitive solid electrolyte interphase formation, and lithium dendrite growth. To overcome these limitations, dendrite-free liquid metal anodes exploiting composite solutions of alkali metals, aromatics, and ether solvents have been studied. These composite solutions are much easier to control and stabilize than molten alkali metals or alkali metal alloys. Herein, we provide a detailed overview of complex solutions of alkali metals, aromatics, and ether solvents, including their development history, principles, and characteristics. In addition, the obstacles limiting their practical applications and the future research directions are discussed/proposed for the benign development of this field.