California-based Imergy Power Systems has developed a process for producing flow batteries with recycled vanadium from mining slag, oil field sludge, fly ash and other forms of industrial waste. The company hopes to use this process to reduce the cost of battery-based energy storage systems.
Imergy says its process enables it to produce flow batteries with vanadium at a 98% purity level that can be harvested from environmental waste sites, as opposed to the 99% purity typically used with mined vanadium. By extracting vanadium from slag, Imergy says it will lower the cost of obtaining and processing the material by 40% relative to competitors.
As a result of this technology and other developments, Imergy says it will be able to lower the cost of its flow batteries from the industry's current benchmark of $500/kWh to under $300/kWh.
Imergy's strategy is to work with oil and mining companies to develop a supply of raw materials for its flow batteries. Thousands of tons of vanadium brought to the surface through worldwide petroleum operations every year end up in sludge deposits, the company says. Also, tons of vanadium accumulate in copper mine tailings.
‘We're taking industrial sludge and turning it into a source of clean energy,’ says Bill Watkins, CEO of Imergy Power Systems. ‘At the same time, we're lowering the cost and increasing the performance of energy storage, which is going to expand the market.’