Electrolyte solution chemistry and interface dynamics for fast-charging sustainable anion shuttle batteries

The demand for sustainable and fast-charging energy storage systems has grown significantly, yet traditional lithium-ion batteries (LIBs) face challenges related to costly resources and sluggish charge transport kinetics. As a promising alternative, dual-ion batteries (DIBs), also known as anion-shuttle batteries, have gained attention for their high operational voltage and ultrafast charging capabilities. Unlike conventional rocking-chair batteries, DIBs utilize both cations and anions as charge carriers, reducing rate-limiting steps and eliminating long-range ion migration. This review provides a comprehensive analysis of the critical factors influencing DIB performance, with a particular focus on anion solvation structures, diffusion kinetics, electrolyte stability, and interfacial charge transfer mechanisms. We also explore how interface engineering enhances charge transfer efficiency and extends battery lifespan. In particular, we examine the role of cathode electrolyte interphase (CEI) and solvation dynamics in stabilizing the electrode-electrolyte interface. By providing a comprehensive understanding of chemistry and dynamics in DIBs, this review outlines future research directions for advancing sustainable DIBs technology.