Chemisting

If you have looked into flow batteries for any length of time, you will have found that the ferrocyanide/ferricyanide redox couple ( [Fe(CN)6] 4−, Fe(CN)6] 3−) is one of the most widely used in the field.

On a previous post I discussed my first attempts at reproducing the Na-sulfamate based Zn-Br battery published by a group of Chinese researchers.

A recent Chinese Nature paper showed how Sodium sulfamate can be used in Zn-Br batteries to sequester active Br2 into an N-bromosulfamate that is much less aggressive, much more water soluble and even more easily electrochemically reversible than elemental

Zinc bromide flow batteries have been researched very extensively during the past 30 years.

All-Fe flow batteries are very promising due to iron’s high abundance, low toxicity and low cost.