Argonne flows into utility-scale battery research

June 28, 2012

ARGONNE, Ill. ― Scientists at the U.S. Department of Energy's (DOE) Argonne National Laboratory have developed an all-organic non-aqueous lithium-ion redox flow battery that would help expand use of large-scale solar and wind energy on the nation's electrical  grid.

The non-aqueous electrolyte of the Argonne-developed flow battery is more electrochemically stable than the older and not widely commercialized aqueous redox flow batteries that have been developed since the 1960s. That added stability allows the flow battery to use electrochemically active materials that operate at higher cell voltages, said principal investigator Andrew Jansen, a chemical engineer.

For now, he said the Argonne flow battery technology, which has gone through up to 50 cycles, has passed the proof-of-concept stage.

"The next step," he said, "is to find a more robust electro-active organic chemical compound that can be concentrated for the negative electrode and positive electrode sides of the battery. The greater the concentration, the higher the energy density and the smaller and more economical the battery will be to manufacture.

"We're also working on a non-flammable solvent system to increase the safety of the system," Jansen said. "We must also be able to ensure that the battery's chemicals will remain stable over a 20-year life span."

The need for large-scale energy storage technologies is expected to grow as the Renewable Portfolio Standard is applied. Large amounts of energy from renewable sources like wind and solar cannot be easily put directly on to the electrical grid because they do not generate a consistent flow of power. Instead, a portion of the power they generate must be stored for later use when demand is high and released in a regulated way that maintains a level load of electricity on the grid.

The Argonne Li-ion flow battery uses 2,5-di-tert-butyl-1,4-bis(2-methoxyethoxy) benzene, or DBBB, redox shuttle, an overcharge protection additive, as its high-potential  active species and a variety of quinoxaline-based species as its low-potential species. It has demonstrated excellent overcharge properties with little negative effect to the cell system.

This research was published in Advanced Energy Materials in an article entitled "An All-Organic Non-aqueous Lithium-Ion Redox Flow Battery."

This research was supported by the Argonne’s Laboratory Directed Research and Development program and the lab's Director's Postdoctoral Fellowship program.

Argonne National Laboratory seeks solutions to pressing national problems in science and technology. The nation's first national laboratory, Argonne conducts leading-edge basic and applied scientific research in virtually every scientific discipline. Argonne researchers work closely with researchers from hundreds of companies, universities, and federal, state and municipal agencies to help them solve their specific problems, advance America's scientific leadership and prepare the nation for a better future. With employees from more than 60 nations, Argonne is managed by UChicago Argonne, LLC for the U.S. Department of Energy's Office of Science.