Research gets closer to producing revolutionary battery to power renewable energy industry

March 14, 2018

LAWRENCE -- Any resident of the Great Plains can attest to the massive scale of wind farms that increasingly dot the countryside. In the Midwest and elsewhere, wind energy accounts for an ever-bigger slice of U.S. energy production: In the past decade, $143 billion was invested into new wind projects, according to the American Wind Energy Association.

However, the boom in wind energy faces a hurdle -- how to effectively and cheaply store energy generated by turbines when the wind is blowing, but energy requirements are low.

"We get a lot of wind at night, more than at daytime, but demand for electricity is lower at night, so, they're dumping it or they lock up turbines -- we're wasting electricity," said Trung Van Nguyen, professor of petroleum & chemical engineering at the University of Kansas. "If we could store this excess at night and sell or deliver it during daytime at peak demand, this would allow wind farm owners to make more money and leverage their investment. At the same time, you deploy more wind energy and reduce demand for fossil fuels."

Since 2010, Nguyen has headed research to develop an advanced hydrogen-bromine flow battery, an advanced industrial-scale battery design -- it would be roughly the size of a semi-truck -- that engineers have strived to develop since the 1960s. It could work just as well to store electricity from solar farms, to be discharged overnight when there's no sun.

Funded first by the National Science Foundation and later by the Advanced Research Projects Agency-Energy, Nguyen has worked with researchers from the University of California at Santa Barbara, Vanderbilt University, the University of Texas at Arlington and Case Western Reserve University. Along the way, Nguyen has overseen breakthrough work on key components of hydrogen-bromine battery design.

For one, there's the electrode Nguyen developed at KU. A battery's electrode is where the electrical current enters or leaves the battery when it's discharged. To be maximally efficient, an electrode needs a lot of surface area. Nguyen's team has developed a higher-surface-area carbon electrode by growing carbon nanotubes directly on the carbon fibers of a porous electrode.

"Before our work, people used paper-carbon electrodes and had to stack electrodes together to generate high-power output," he said. "The electrodes had to be a lot thicker and more expensive because you had to use multiples layers -- they were bulkier and more resistive. We came up with a simple but novel idea to grow tiny carbon nanotubes directly on top of carbon fibers inside of electrodes -- like tiny hairs -- and we boosted the surface area by 50-70 times. We solved the high-surface requirement for hydrogen-bromine battery electrodes."

A key issue remaining before a hydrogen-bromide battery can be marketed successfully is the development of an effective catalyst to accelerate the reactions on the hydrogen side of the battery and provide higher output while surviving the extreme corrosiveness in the system. Now, with funding from an NSF sub-award through a private company called Proton OnSite, Nguyen is verging on solving this last barrier.

"I think we're on the verge of a real breakthrough," he said. "We need a durable catalyst, something that has the same activity as the best catalyst out there, but that can survive this environment. Our previous material didn't have sufficient surface area to give enough power output. But I've been able to continue to work on this rhodium sulfide catalyst. I think we've figured out a way to increase surface area. We now have a better way, and we may publish that in three to six months -- we have some minor issues to resolve, but I think we'll have a suitable material for the hydrogen reaction in this system."

The new results to develop an industrial scale advanced hydrogen-bromine flow battery will be presented at the meeting of the Electrochemical Society in Seattle this May.

Indeed, Nguyen -- who has founded several startup companies over his research career -- noted the new hydrogen-bromine battery soon could be commercialized, and easily could be scaled to MW (power) MWh (energy) scales, coming in modular container form, about 1MWh in a full-size container. But he cautioned it could only be used in remote, industrial sites -- places like wind and solar farms, where the huge batteries likely would be buried underground.

"This energy storage system, because of its corrosiveness, isn't suitable for residential or commercial systems," he said. "Bromine is like chlorine gas. Dig a hole, line it with cement or plastic, drop this battery down and cover it up -- it should be in an enclosed or sealed system to prevent leakage or emission of bromine gas. This will be suitable only for large-scale remote energy storage like solar farms and wind farms."

The KU researcher said the rise of renewable energy would depend on technology breakthroughs that make the economics attractive to energy producers and investors, and he hoped his new battery design could play a part.

"The way we use fossil fuel for energy is very inefficient, wasteful and generates greenhouse gasses," Nguyen said. "For fossil fuels, you make the initial investment, and also you pay for operation every day -- pay for coal or for natural gas for rest of the life of the power plant. Once you make the initial investment in renewable, the electricity you make is free."

University of Kansas

Related Renewable Energy Articles from Brightsurf:

Creating higher energy density lithium-ion batteries for renewable energy applications
Lithium-ion batteries that function as high-performance power sources for renewable applications, such as electric vehicles and consumer electronics, require electrodes that deliver high energy density without compromising cell lifetimes.

Renewable energy targets can undermine sustainable intentions
Renewable energy targets (RETs) may be too blunt a tool for ensuring a sustainable future, according to University of Queensland-led research.

Intelligent software for district renewable energy management
CSEM has developed Maestro, an intelligent software application that can manage and schedule the production and use of renewable energies for an entire neighborhood.

Renewable energy transition makes dollars and sense
New UNSW research has disproved the claim that the transition to renewable electricity systems will harm the global economy.

Renewable energy advance
In order to identify materials that can improve storage technologies for fuel cells and batteries, you need to be able to visualize the actual three-dimensional structure of a particular material up close and in context.

Illuminating the future of renewable energy
A new chemical compound created by researchers at West Virginia University is lighting the way for renewable energy.

Using fiber optics to advance safe and renewable energy
Fiber optic cables, it turns out, can be incredibly useful scientific sensors.

Renewable energy developments threaten biodiverse areas
More than 2000 renewable energy facilities are built in areas of environmental significance and threaten the natural habitats of plant and animal species across the globe.

Could water solve the renewable energy storage challenge?
Seasonally pumped hydropower storage could provide an affordable way to store renewable energy over the long-term, filling a much needed gap to support the transition to renewable energy, according to a new study from IIASA scientists.

Scientists take strides towards entirely renewable energy
Researchers have made a major discovery that will make it immeasurably easier for people (or super-computers) to search for an elusive 'green bullet' catalyst that could ultimately provide entirely renewable energy.

Read More: Renewable Energy News and Renewable Energy Current Events is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to