New Li-Air Battery Design Promises Unprecedented Energy Density

big picture: Among the many alternative solutions to traditional lithium-ion batteries, researchers are experimenting with lithium-air designs. A new innovation in space could solve many of the problems that have previously surfaced in this technology.

A new paper published in The science describes the chemistry of the new lithium-air battery, an innovative design that has the potential to deliver much greater energy density than traditional lithium-ion battery technology. This could be a real breakthrough in the battery market and a possible revolution for transportation and heavy vehicles such as airplanes, trains and even submarines.

The new battery can withstand over 1,000 recharge cycles with a slight reduction in energy efficiency of five percent and zero impact on Coulomb efficiency. This means that all of the original battery material was still active, with no irreversible side reactions during charge/recharge cycles.

Design conceived Researchers at the Illinois Institute of Technology are using a ceramic-polyethylene oxide composite solid electrolyte that is safer and more efficient than liquid electrolytes. Ceramic and polymeric materials used as solid electrolytes have their drawbacks when used separately, but in combination they can provide both high ionic conductivity of ceramics and high polymer stability.

The composite electrolyte was able to operate at room temperature, a first for a lithium-air battery. According to Mohammad Asadi, an assistant professor of chemical engineering at the Illinois Institute of Technology, the solid-state electrolyte “provides about 75 percent of the total energy density.” There is still room for further improvement, and by minimizing thickness without sacrificing performance, the new design could deliver “very, very high” energy density.

A lithium-air battery can potentially store one kilowatt-hour per kilogram or more, four times that of current lithium-ion technology. The Science article says that a lithium-air battery based on the formation of lithium oxide (Li2O) could theoretically provide an energy density “comparable to the density of gasoline.”

Going forward, Asadi plans to work with private sector partners to try and optimize the design for production. The researcher says the new technological breakthrough has opened a “big window of opportunity” for bringing lithium-air batteries to market.