Dutch manufacturer makes switch from bromine to iron flow batteries due to ‘geopolitical turbulence’

Dutch long-duration energy storage manufacturer Elestor has announced a change in the chemistry used in its flow batteries due to “recent and ongoing geopolitical turbulence.”

The Arnhem-based company is abandoning hydrogen-bromine flow battery technology in favor of hydrogen-iron (H₂Fe) chemistry.

Announcing the change on its website, Elestor CEO Hylke van Bennekom said the change, which has been under wraps for months, has been made after years of R&D and in discussion with the company’s commercial partners and its council of scientists and engineers.

“The most crucial criteria that is on everyone’s mind these days relates to international relations,” wrote Van Bennekom, on the Elestor website. “Recent and ongoing geopolitical turbulence has pushed energy security; national and regional energy resilience; and robust energy generation and distribution to the top of the agendas in many parts of the world. 

“Energy independence might be a pipe dream for most, or perhaps all countries but it is still possible for many countries and regions to reduce their reliance on energy or technology imports from hostile nations. They can do this by transitioning to a locally sourced and constructed clean energy system based on renewables such as solar and wind power, with backbone support of an affordable, robust, and reliable large-scale, long-duration energy storage solution. Our hydrogen-iron flow battery represents the missing link in this equation.”

While admitting bromine is also an abundant material, the CEO said iron is even more readily available worldwide, including in areas far from the seawater bromine can be extracted from.

Van Bennekom said the processing of iron is easier than bromine – which is produced chiefly in Israel, Jordan, China, and the United States – and said iron is often considered a waste product of other chemical processes. Easy to store and transport, according to the CEO, iron can also sit alongside less problematic materials in a battery system and, for instance, removes the need for Elestor to use “forever plastics” which do not break down upon disposal. That, in turn, makes securing regulatory approval easier, added the executive.

The chief executive conceded hydrogen-iron flow batteries would offer less power and energy density than their hydrogen-bromine predecessors but said they would still comfortably outcompete other flow battery materials.

The CEO’s message did not explain how the change in battery chemistry will affect Elestor’s commercialization timetable, if at all.

The company’s website indicates Elestor has completed pilot testing projects but those which specify the chemistry used all feature hydrogen-bromine technology. Elestor says it is also completing containerized installations.