Iron flow batteries are coming to Australia

The scramble to develop  better and cheaper batteries to bolster the sustainable energy revolution continues with liquid-based flow batteries said to provide a cheaper, longer-lasting and less resource-intensive way to store power on energy grids.

Researchers at Queensland University of Technology are hoping to diversify the grid further, with the commissioning of an iron flow battery at its National Battery Testing Centre in Banyo in Brisbane.

“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 project lead Dr Joshua Watts.

Watts says that the battery will be 12 metres long, and a nominal 75 kW/400 kWh.

“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.”

For more on flow batteries, read our explainer.

The power and energy storage (kW/kWh) is small compared to other, vanadium-based flow batteries scheduled to hit the Australian grid, which can be up to 4000 kW/16,000 kWh. The world’s largest flow battery, in China, is 25 times larger than that again – roughly the same size as big Australian lithium-ion batteries.

But iron-flow batteries will be fully recyclable, as well as cheap and easy to scale because they rely on non-toxic iron chloride.

“You just increase the electrolyte volume, and you increase the capacity. You only need to make the tank bigger,” says Watts.

Watts adds that the other components of iron flow batteries – mostly PVC pipes, water pumps and fibreglass tanks – makes them straightforward to manufacture locally.

Australia’s first, large-scale iron flow battery manufacturing facility is also being constructed at Maryborough, getting developed by Energy Storage Industries – Asia Pacific (ESI).

ESI, along with the Future Battery Industries Cooperative Research Centre, is collaborating with QUT to test the iron flow battery.

“We’ll be going through – over the next three months or so – a rigorous testing regime in collaboration with potential off takers to test the battery under different use conditions to get these batteries out into the wild supporting the energy grid as soon as possible,” says Watts.