Water-soluble complexing agent additive makes bromide aqueous flow batteries scalable, sustainable, safe and affordable

https://engineering.wisc.edu/news/engineered-additive-makes-low-cost-renewable-energy-storage-a-possibility/

"soft-hard zwitterionic trapper organic molecules encapsulates bromide ions while allowing them to remain water-soluble, but since now larger, can’t pass through membrane... ions phase-stable so don’t separate out of electrolyte or create toxic bromine gas... increased efficiency, longevity... functioned without decay for almost two months compared to ones without it, which typically fail within a day (goal: 10 or 20 years)... long-term energy-storage"