Australian researchers have commissioned the biggest large-scale iron flow battery - and the first of its kind - outside of the United States.

The QUT-operated National Battery Testing Centre (NBTC) is collaborating with Energy Storage Industries - Asia Pacific (ESI) and the Future Battery Industries Cooperative Research Centre (FBICRC) to enable large-scale energy storage solutions to help meet clean energy targets set by state and federal governments.

A flow battery contains two chemical solutions, separated by a membrane, with electricity stored and released through changes in the oxidation state of metal ions dissolved in solution.

“This particular battery shows great potential in providing large-scale long-duration energy storage solutions to store energy for distribution when the wind is not blowing and the sun is not shining,” says NBTC Project lead Dr Joshua Watts.

“It’s not the type of battery you would buy for the backyard, but more targeted toward large-scale solar and wind farms, or new community developments where they're looking to build in more localised energy generation and distribution networks.”

The ‘Energy Warehouse’ iron flow battery being commissioned and tested at the NBTC is a 12-metre-long containerised system and is designed to be used for large-scale energy generation and distribution support for the electricity grid.

“Energy Warehouse systems have the potential to store solar energy generated by residential solar arrays to assist with the management of excess energy that the current electricity transmission infrastructure can't handle,” Dr Watts said.

He says lithium batteries are more compact, but the cost of scaling lithium batteries for long-duration storage applications can potentially be an issue for large-scale applications.

Iron flow batteries are better suited for large-scale applications, offering ease of scalability for long-duration energy storage applications.

“Iron flow batteries are well suited for long-duration applications due to the nature of the energy storage mechanism, which is achieved through dissolved metal salts in aqueous solution. So, you just increase the electrolyte volume, and you increase the capacity. You only need to make the tank bigger,” Dr Watts said.

Other advantages of iron flow batteries are that they are environmentally benign, fully recyclable and offer a potential lower cost per kWh for long-duration storage applications.

Dr Watts said the potential for local manufacturability of the iron flow systems is high because they use simplified componentry. They mainly comprise PVC pipes, water pumps and fibreglass tanks assembled in a 12-metre container.

“There's potential then to reskill workers moving out of the coal-fired power station industry who have similar skill sets in maintaining plant equipment,” he said. 

Dr Watts also said that iron flow batteries have an advantage when it comes to enlarging, repurposing or recycling.

“Iron flow batteries utilise a weakly acidic iron chloride solution which is non-toxic, simplifying the refurbishment and recycling process for these systems,” said Dr Watts.

The Queensland Government’s Energy and Jobs Plan - released in September 2022 - sets a target of 70 per cent renewables in the energy grid by 2032.

Deputy Premier Steven Miles said the Queensland Energy and Jobs Plan was already creating new jobs in new industries like battery manufacturing.

“Large-scale iron flow batteries are the cutting edge of the energy revolution, and that innovation is happening right here in Queensland thanks to the support of the Palaszczuk Government,” the Deputy Premier said.

“As we invest in more solar and more wind, the demand for large-scale batteries and storage will increase to ensure Queensland’s energy is reliable and affordable, these new batteries are perfect to support our energy grid.”