#ultra-low

Lithium batteries to run at ultra-low temperatures

Engineers at the University of California San Diego have developed a breakthrough in electrolyte chemistry that enables lithium batteries to run at temperatures as low as -60 degrees Celsius with excellent performance. The new electrolytes also enable electrochemical capacitors to run as low as -80 degrees Celsius — their current low-temperature limit is -40 degrees Celsius. While the technology enables extreme low-temperature operation, high performance at room temperature is still maintained. The new electrolyte chemistry could also increase the energy density and improve the safety of lithium batteries and electrochemical capacitors.

The work will be published online by the journal Science.

The technology could allow electric vehicles in cold climates to travel farther on a single charge. It could also be used to power craft in the extreme cold, such as high atmosphere WiFi drones and weather balloons, satellites, interplanetary rovers and other aerospace applications.

The batteries and electrochemical capacitors the researchers developed are especially cold hardy because their electrolytes are made from liquefied gas solvents-gases that are liquefied under moderate pressures-which are far more resistant to freezing than standard liquid electrolytes. The new lithium battery electrolyte was made using liquefied fluoromethane gas. Electrochemical capacitor electrolyte was made using liquefied difluoromethane gas.

“Deep de-carbonization hinges on the breakthroughs in energy storage technologies. Better batteries are needed to make electric cars with improved performance-to-cost ratios. And once the temperature range for batteries, ultra-capacitors and their hybrids is widened, these electrochemical energy storage technologies can be adopted in much more emerging markets. This work shows a promising pathway and I think the success of this unconventional approach can inspire more scientists and researchers to explore the unknown territories in this research area,” said Shirley Meng, a nanoengineering professor at the UC San Diego Jacobs School of Engineering and the study’s senior author. Meng leads the Laboratory for Energy Storage and Conversion and is the director of the Sustainable Power and Energy Center, both at UC San Diego.