High Stability Alkaline Zinc-Ferricyanide Flow Battery With Multi-Coordination Electrolyte Additive for Suppressing...

Grid-scale energy storage technologies are critical for stabilizing power grids increasingly reliant on intermittent renewable energy sources. Among these technologies, aqueous alkaline zinc-ferricyanide flow batteries (AZFFBs) are promising candidates due to their low cost, high safety, and rapid kinetics. However, their practical deployment is hindered by the formation of "dead zinc", which can cause irreversible capacity loss and block flow channels. Herein, we identify the growth of irreversible crystal buds as the primary cause of macroscopic zinc pulverization, which leads to "dead zinc" formation in AZFFBs. To address this issue, we introduce a multi-coordination electrolyte additive, panthenol (PAN), which simultaneously coordinates with Zn(OH)₄ ^2- to homogenize ion transport at the electrode interface and promotes the formation and re-atomization of reversible crystal buds. This strategy results in a 15-fold increase in the cycling life of Zn||K₄[Fe(CN)₆] full batteries, along with 2.1%, 3.1%, and 1.2% improvements in Coulombic efficiency, energy efficiency, and voltage efficiency, respectively. This work clarifies the formation mechanism of "dead zinc" in AZFFBs and proposes an efficient inhibition of zinc pulverization approach, bridging the gap between renewable energy generation and grid-scale storage.