Rethinking the Shuttle Effect: Intrinsic Phenomenon and Regulatory Opportunities in Battery Design

Abstract The rising demand for high‐energy, long‐lasting energy storage drives interest from conventional lithium‐ion batteries to new systems such as lithium–sulfur (Li‐S), lithium–phosphorus (lI‐p), and metal–air, which offer higher capacities, lower costs, and improved safety. Early studies of the shuttle effect focus on polysulfide dissolution and diffusion in Li–S cells and on strategies to curb performance loss. Subsequent investigations reveal analogous dissolution–diffusion behaviors in Li–P, metal–air, and Mn/V‐based batteries, all falling under shuttle phenomena. Traditionally regarded as detrimental, causing self‐discharge, electrolyte contamination, and interfacial degradation, the shuttle effect has been largely approached with a “suppress‐at‐all‐costs” mindset. However, this overlooks that controlled dissolution can accelerate redox kinetics, enhance active‐material distribution, and reactivate protective interphases. This review classifies shuttle‐prone systems into two categories: i) non‐reactive dissolution, where electrode materials directly solubilize into the electrolyte, and ii) reactive dissolution, where soluble intermediates form through secondary reactions. An unified dissolution–diffusion model describing soluble‐species formation and migration is proposed. By synthesizing literature evidence, both drawbacks and benefits of shuttle processes are highlighted. The concept of a “balanced shuttle state” is introduced, emphasizing that optimized, not eliminated dissolution can enable next‐generation energy storage devices with improved kinetics and stability.