Are zinc-based flow batteries a good choice for large scale energy storage?

The ultralow cost neutral Zn/Fe RFB shows great potential for large scale energy storage. Zinc-based flow batteries have attracted tremendous attention owing to their outstanding advantages of high theoretical gravimetric capacity, low electrochemical potential, rich abundance, and low cost of metallic zinc.

Are zinc-iron flow batteries suitable for grid-scale energy storage?

Among which, zinc-iron (Zn/Fe) flow batteries show great promise for grid-scale energy storage. However, they still face challenges associated with the corrosive and environmental pollution of acid and alkaline electrolytes, hydrolysis reactions of iron species, poor reversibility and stability of Zn/Zn 2+ redox couple.

Are neutral zinc–iron flow batteries a good choice?

Neutral zinc–iron flow batteries (ZIFBs) remain attractive due to features of low cost, abundant reserves, and mild operating medium. However, the ZIFBs based on Fe (CN) 63– /Fe (CN) 64– catholyte suffer from Zn 2 Fe (CN) 6 precipitation due to the Zn 2+ crossover from the anolyte.

How effective is a zinc-iron flow battery?

Early experimental results on the zinc-iron flow battery indicate a promising round-trip efficiency of 75% and robust performance (over 200 cycles in laboratory). Even more promising is the all-iron FB, with different pilot systems already in operation.

Are zinc anode materials a problem for flow batteries?

The existing studies revealed that for the zinc-based flow batteries, zinc anode materials are facing challenges, such as poor redox reversibility, low efficiency, dendrite formation during plating/stripping process, and short cycle life. These concerns greatly hampered the improvements of cell performance and lifespan [35, 36].

What is a neutral zinc-iron redox flow battery?

A high performance and long cycle life neutral zinc-iron redox flow battery. The neutral Zn/Fe RFB shows excellent efficiencies and superior cycling stability over 2000 cycles. In the neutral electrolyte, bromide ions stabilize zinc ions via complexation interactions and improve the redox reversibility of Zn/Zn 2+.