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China spins up giant battery built with US-patented tech

World's largest VRFB was built with inadvertent help from the Department of Energy

The world's largest vanadium redox flow battery (VRFB) has been connected to the grid in Dalian, China, where it was built using technology patented in the United States.

With a current capacity of 100MW/400MWh and plans to double it, the Dalian VRFB will reportedly be able to meet the daily energy needs of 200,000 people, the Chinese Academy of Sciences (CAS) said. The battery will be used to manage supplies during peak power demand periods, and could allow electricity companies in the Dalian region to adopt more renewables to feed the system. 

VRFBs are free of lithium-ion and are far safer than traditional batteries, instead relying on mixtures of liquid electrolytes and acids. VRFBs can hold a charge for far longer than traditional batteries as well, and are also designed to be charged and discharged for decades without degrading.

The Dalian VRFB dwarfs other projects – Australia's largest VRFB only boasts 2MW/8MWh of capacity, and a similar test project in the San Diego area recently stood up a similarly sized battery. Other large VRFB projects are still far smaller, like the Sumitomo battery in Hokkaido, Japan, that was brought online earlier this year. It has a capacity of 17MW/51MWh and was described as one of the world's largest VRFBs.

American tax dollars at work

As reported in August, the VRFB built in Dalian appears to be one designed at Pacific Northwest National Laboratory (PNNL) that cost US taxpayers $15 million dollars to develop, and for which the US government owns the patent. 

Other VRFBs lack PNNL's special acid/electrolyte mixture, which the lab said was twice as powerful as other vanadium formulae and could last 30 years without losing capacity, hence their far smaller capacities. 

PNNL's recipe isn't being manufactured anywhere in the US, and through a series of moves ended up in the hands of Dalian Rongke Power Co. Ltd, which stepped in when PNNL's lead VRFB scientist Gary Yang claimed to not be able to find a US company to invest in the technology's production.

Yang granted a sublicense to Rongke to manufacture PNNL VRFBs in China, which has since been transferred to Dutch company Vanadis Power, which manufactures PNNL's batteries, dubbed ReFlex, in China. Vanadis partner Bolong New Materials, also based in Dalian, is described as the exclusive producer of ReFlex acid-electrolyte material – the secret sauce cooked up at PNNL.

Earlier this month, US Senators John Barasso (R-WY and ranking Republican on the Senate Committe on Energy and Natural Resources) and Joni Ernst (R-IA) sent a letter to the Department of Energy asking for an investigation into the loss of PNNL's VRFB technology to China.

Dalian Rongke, the senators said, has become the largest VRFB manufacturer in the world since acquiring the US patent. The pair expressed concern that the DoE was overtly derelict of its duties "and that this case may be emblematic of a department that routinely and flippantly permits government-funded technology to be transferred to China." ®

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