Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

“Wetting” a Battery’s Appetite for Renewable Energy Storage

04.08.2014

New liquid alloy electrode improves sodium-beta battery performance

Sun, wind and other renewable energy sources could make up a larger portion of the electricity America consumes if better batteries could be built to store the intermittent energy for cloudy, windless days. Now a new material could allow more utilities to store large amounts of renewable energy and make the nation’s power system more reliable and resilient.

A paper published today in Nature Communications describes an electrode made of a liquid metal alloy that enables sodium-beta batteries to operate at significantly lower temperatures. The new electrode enables sodium-beta batteries to last longer, helps streamline their manufacturing process and reduces the risk of accidental fire.

“Running at lower temperatures can make a big difference for sodium-beta batteries and may enable batteries to store more renewable energy and strengthen the power grid,” said material scientist Xiaochuan Lu of the Department of Energy’s Pacific Northwest National Laboratory.

Need for energy storage, but challenges remain
More than 300 megawatts of large, cargo container-sized sodium-beta batteries are running in the United States, Japan and Europe, according to Dupont Energy Consulting. They often store electricity generated by rows of solar panels and wind turbines.

But their broader use has been limited because of their high operating temperature, which reaches up to 350 degrees Celsius, or more than three times the boiling point of water. Such high operating temperatures requires sodium-beta batteries to use more expensive materials and shortens their operating lifespans. PNNL researchers set out to reduce the battery’s operating temperature, knowing that could make the battery more efficient and last longer.

The traditional design of sodium-beta batteries consists of two electrodes separated by a solid membrane made of the ceramic material beta alumina. There are two main types of sodium-beta batteries, based on the materials used for the positive electrode: those that use sulfur are called sodium-sulfur batteries, while those that use nickel chloride are known as ZEBRA batteries. Electricity is generated when electrons flow between the battery's electrodes.

Lowering the battery’s operating temperature creates several other technical challenges. Key among them is getting the negative sodium electrode to fully coat, or “wet” the ceramic electrolyte. Molten sodium resists covering beta alumina’s surface when it’s below 400 degrees Celsius, causing sodium to curl up like a drop of oil in water, making the battery less efficient. For decades researchers have tried to overcome this by applying different coatings to the membrane.

New electrode offers different take
Lu and his PNNL colleagues took an entirely different approach to the wettability problem: modifying the negative electrode. Instead of using pure sodium, they experimented with sodium alloys, or sodium blended with other metals. The team determined a liquid sodium-cesium alloy spreads out well on the beta alumina membrane.

PNNL’s new electrode material enables the battery to operate at lower temperatures. Instead of the 350 degrees Celsius at which traditional sodium-beta batteries operate, a test battery with the new electrode worked well at 150 degrees – with a power capacity of 420 milliampere-hours per gram, matching the capacity of the traditional design.

Batteries with the new alloy electrode also retain more of their original energy storage capacity. After 100 charge and discharge cycles, a test battery with PNNL’s electrode maintained about 97 percent of its initial storage capacity, while a battery with the traditional, sodium-only electrode maintained 70 percent after 60 cycles.

A battery with a lower operating temperature can also use less expensive materials such as polymers -- which would melt at 350 degrees Celsius -- for its external casing instead of steel. Using less expensive and sensitive materials would also help streamline the battery’s manufacturing process. This offsets some of the increased cost associated with using cesium, which is more expensive than sodium.

The PNNL research team is now building a larger electrode to test with a larger battery to bring the technology closer to the scale needed to store renewable energy.

This research was supported by DOE’s Office of Electricity Delivery and Energy Reliability and internal PNNL funding.

REFERENCE: Xiaochuan Lu, Guosheng Li, Jin Y. Kim, Donghai Mei, John P. Lemmon, Vincent L. Sprenkle, Jun Liu, “Liquid Metal Electrode to Enable Ultra-Low Temperature Sodium0Beta Alumina Batteries for Renewable Energy Storage,” Nature Communications, DOI: 10.1038/ncomms5578, Aug. 1, 2014.


Interdisciplinary teams at Pacific Northwest National Laboratory address many of America's most pressing issues in energy, the environment and national security through advances in basic and applied science. Founded in 1965, PNNL employs 4,300 staff and has an annual budget of about $950 million. It is managed by Battelle for the U.S. Department of Energy’s Office of Science. As the single largest supporter of basic research in the physical sciences in the United States, the Office of Science is working to address some of the most pressing challenges of our time. For more information on PNNL, visit the PNNL News Center, or follow PNNL on Facebook, Google+, LinkedIn and Twitter.

Franny White | newswise
Further information:
http://www.pnnl.gov

Further reports about: Energy PNNL Pacific Storage battery beta capacity electrode electrodes expensive materials sodium temperatures

More articles from Interdisciplinary Research:

nachricht When the Brain Grows, the IQ Rises
16.02.2016 | Technische Universität Chemnitz

nachricht Standard BMI inadequate for tracking obesity during leukemia therapy
29.01.2016 | Children's Hospital Los Angeles

All articles from Interdisciplinary Research >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Nuclear Pores Captured on Film

Using an ultra fast-scanning atomic force microscope, a team of researchers from the University of Basel has filmed “living” nuclear pore complexes at work for the first time. Nuclear pores are molecular machines that control the traffic entering or exiting the cell nucleus. In their article published in Nature Nanotechnology, the researchers explain how the passage of unwanted molecules is prevented by rapidly moving molecular “tentacles” inside the pore.

Using high-speed AFM, Roderick Lim, Argovia Professor at the Biozentrum and the Swiss Nanoscience Institute of the University of Basel, has not only directly...

Im Focus: 2+1 is Not Always 3 - In the microworld unity is not always strength

If a person pushes a broken-down car alone, there is a certain effect. If another person helps, the result is the sum of their efforts. If two micro-particles are pushing another microparticle, however, the resulting effect may not necessarily be the sum their efforts. A recent study published in Nature Communications, measured this odd effect that scientists call “many body.”

In the microscopic world, where the modern miniaturized machines at the new frontiers of technology operate, as long as we are in the presence of two...

Im Focus: Tiny microbots that can clean up water

Researchers from the Max Planck Institute Stuttgart have developed self-propelled tiny ‘microbots’ that can remove lead or organic pollution from contaminated water.

Working with colleagues in Barcelona and Singapore, Samuel Sánchez’s group used graphene oxide to make their microscale motors, which are able to adsorb lead...

Im Focus: ORNL researchers discover new state of water molecule

Neutron scattering and computational modeling have revealed unique and unexpected behavior of water molecules under extreme confinement that is unmatched by any known gas, liquid or solid states.

In a paper published in Physical Review Letters, researchers at the Department of Energy's Oak Ridge National Laboratory describe a new tunneling state of...

Im Focus: Bionic Lightweight Design researchers of the Alfred Wegener Institute at Hannover Messe 2016

Honeycomb structures as the basic building block for industrial applications presented using holo pyramid

Researchers of the Alfred Wegener Institute (AWI) will introduce their latest developments in the field of bionic lightweight design at Hannover Messe from 25...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

The “AC21 International Forum 2016” is About to Begin

27.04.2016 | Event News

Soft switching combines efficiency and improved electro-magnetic compatibility

15.04.2016 | Event News

Grid-Supportive Buildings Give Boost to Renewable Energy Integration

12.04.2016 | Event News

 
Latest News

Expanding tropics pushing high altitude clouds towards poles, NASA study finds

06.05.2016 | Earth Sciences

IU-led study reveals new insights into light color sensing and transfer of genetic traits

06.05.2016 | Life Sciences

Thievish hoverfly steals prey from carnivorous sundews

06.05.2016 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>