GoKawiilAnalysis explains why symmetric ferrocyanide flow batteries remain unbuilt
A technical review examines the ferrocyanide/ferricyanide redox couple, prized in flow batteries for its stability, kinetics and solubility, and asks why no one has built a symmetric flow battery using it on both electrodes. The piece explains that ferrocyanide reacts with heavy metal cations like zinc or iron to form insoluble Prussian blue compounds, blocking the metal-plating side of such a design, and notes that even chelation workarounds using pyrophosphates lead to poor long-term cycling stability, as shown by degradation data after 100 cycles.