Nontoxic Battery Slashes Energy Storage Costs

Iron flow battery will slash energy storage costs by 90 percent and eliminate environmental concerns

Funding from Oregon BEST has helped secure a $2.1 million ARPA-E grant from the U.S. Dept. of Energy to Energy Storage Systems, Inc. (ESS), a Portland startup developing a redox flow battery that uses a nontoxic electrolyte solution of iron and table salt and could reduce the cost of energy storage in flow batteries by as much as 90 percent.

The project involves faculty and students at Portland State University who have performed target market analysis for the battery to help ESS determine best strategies for entering the marketplace when the technology is scaled up later this year.

Unlike traditional batteries such as AAs, lead acid, and lithium ion that house all materials inside the battery packaging and have a limited number of charge cycles, redox flow batteries store the electrolyte solution in tanks, and the solution is pumped through the battery depending on the energy capacity required. The electrolyte contains one or more dissolved electroactive elements that flow through an electrochemical cell that converts chemical energy to electricity.

"With redox flow batteries, the charge cycles are virtually limitless, and with our all-iron chemistry, we eliminate the use of toxic chemicals in the electrolyte and dramatically cut the per kilowatt hour cost," said Craig Evans, CEO of ESS, which is located in the Portland State Business Accelerator.

Because the ESS battery uses only iron – one of the most abundant and benign elements on earth – combined with table salt, the electrolyte cost is much less than other flow batteries that rely on vanadium, chromium, bromine, or zinc based electrolytes.

"At a bulk electrolyte cost of less than $17 per kWh of storage capacity, our technology is nearly 90 percent cheaper than its vanadium based electrolyte equivalent," said Evans, who was Director of Design and Product Development at ClearEdge Power before leaving in 2011 to found ESS. "Added benefits are that our electrolyte is nontoxic, 100 percent recyclable and much less corrosive than conventional flow battery electrolytes, with pH similar to wine."

Redox flow batteries can be used to store energy generated by renewables, or to store energy during off-peak hours in areas where Time Of Use pricing tariffs are significantly higher during peak demand periods. ESS is targeting fast food restaurants, warehouses and small grocery stores, where its battery system would charge during the night (or by solar panels during the day), then supply power to the business during the day when energy prices are high.

The company is one of three finalists competing for more than $250,000 in funding from Angel Oregon. Evans said he is looking for funding in order to set up field test sites when the battery technology is scaled up later this year.

The company was awarded a two-phase ARPA-E (Advanced Research Projects Agency-Energy) grant to prove its technology would work and then to scale it up. ARPA-E grants target high-potential, high-impact energy technologies but require a 20 percent match funding from other sources. The $150,000 Oregon BEST funding helped attain that match, securing the ARPA-E grant. ESS also previously received a gap grant from ONAMI in 2011.

"The low-cost battery technology developed by ESS holds significant potential to address a wide range of power grid and energy storage needs, so we're pleased to be helping the company move its clean technology toward the marketplace," said David Kenney, President and Executive Director of Oregon BEST. "If ESS is able to develop this technology into a viable product, there is a very large market and a terrific opportunity to grow the company and the associated jobs."

Bill Jones, a faculty member in the PSU School of Business who directs the Business Strategy Capstone Program, said the ESS project has given students invaluable experience working in a real-world business setting with a real product. "Our student teams on this project found there is a very big market out there for this technology," Jones said. "And although competition in the energy storage sector is growing, ESS's competitive advantage is its innovative technology compared to other energy storage systems with the added advantage of minimal environmental impact."

MEDIA CONTACT: Gregg Kleiner, 541-740-9654
SOURCES: David Kenney, Oregon BEST, 503-725-9849, Craig Evans, CEO, Energy Storage Systems, 503-789-7167; Bill Jones, Portland State University, 503-725-9992

About Energy Storage Systems
Founded in 2011, ESS focuses on laying the groundwork for a future powered by clean and reliable energy. With a team that boasts decades of experience in distributed power generation and energy storage technologies, ESS has developed an extremely cost-effective energy management system that combines a safe, abundant and non-toxic iron electrolyte with our patented flow cell design. This combination of high performance with low cost means that ESS’s technology is ideally suited for applications that range in size from retail energy management to utility-scale renewables integration.