Next generation of battery tech at ARPA-E Technology Showcase

Sustainable Power and Energy Center booth at the ARPA-E Technology Showcase.

A new UC San Diego technology that enables lithium-ion batteries to run at record low temperatures could be useful for the electric vehicles of the future, and this in turn could help address “range anxiety,” especially in cold weather. This project was among the 250+ innovative energy technologies presented at the Advanced Research Projects Agency - Energy (ARPA-E) Technology showcase last week in Washington, D.C.

"We hope this technology extends electric vehicle operation in cold climates, which is currently a known limitation of current electric vehicles," said Cyrus Rustomji, a postdoc in the Sustainable Power and Energy Center (SPEC) at UC San Diego and lead researcher of the project. Rustomji earned his Ph.D. in materials science from UC San Diego in 2015 and now does research with nanoengineering professor Shirley Meng, director of SPEC.

(L-R): Director of ARPA-E Dr. Ellen Williams, Prof. Shirley Meng (director of SPEC at UC San Diego) and Cyrus Rustomji (UC San Diego postdoctoral researcher).

The technology could also enable lithium-ion batteries to operate in extreme environment applications, such as heavy-duty automotive engine cold-start, high-atmosphere drones or balloons, and aerospace missions.

Lithium-ion batteries are commonly found in most rechargeable electronic devices and electric cars. Some advantages of lithium-ion batteries are they charge fairly quickly and don't need to be drained before recharging. But like other batteries, their performance suffers in the cold. That's because because the chemical reactions inside the batteries slow down at low temperatures.

Lithium-ion batteries typically have a low temperature limit of -20 degrees Celsius. The technology developed by Rustomji and coworkers extends lithium-ion battery operation to as low as -60 degrees Celsius. Researchers achieved this exceptionally wide temperature range by replacing the conventional liquid electrolyte in lithium-ion batteries with a liquefied gas electrolyte that's stored under mild pressures.

"Such a chemistry has never been utilized for energy storage devices," said Rustomji. "Most battery technology utilizes a liquid based electrolyte, and a lot of focus is now turning towards solid state electrolytes. But it seems that nobody has yet thought to explore the possibilities of a gaseous type electrolyte. This opens up a new window of electrochemistry in which there are many possible applications and basic science principles to be studied beyond just the energy storage devices we have explored."

The technology garnered much interest during the ARPA-E Technology Showcase. "Visitors were very curious about the technology because it uses a non-conventional electrolyte system, and the low-temperature performance may enable some of their own applications. A scientist from the Jet Propulsion Laboratory was very delighted to see our results and invited us to discuss further and for a possible collaboration," said Rustomji.

Cyrus Rustomji (right) presents a poster of the project titled, "Liquefied Gas Electrolytes for Low Temperature Energy Storage."

Prof. Shirley Meng (left) discusses the project with Werner Kaufmann (right), a technology scout from BASF.

Technology discussion at the SPEC booth including Cyrus Rustomji (left), Prof. Shirley Meng (right) and Dr. Ellen Williams, Director of ARPA-E (second from right).

Cyrus Rustomji (left) demos UC San Diego technology at the SPEC booth at ARPA-E Technology Showcase.

Rustomji's startup, South 8 Technologies, Inc., is working to license and commercialize the liquefied gas electrolyte for applications in the automotive, high-atmosphere and aerospace markets. The company is also seeking partners, investors and funding opportunities.

Visit the Sustainable Power and Energy Center site to keep up with the latest technologies in energy generation, storage and conversion from UC San Diego.