Researchers Develop Superior Lithium-air Battery for EVs

Researchers from the Illinois Institute of Technology and the U.S. Department of Energy’s Argonne National Laboratory recently designed a lithium-air battery that surpasses the energy density of the industry-standard lithium-ion batteries used in most electric vehicles today. 

 

Schematic of a lithium-air battery cell. Image used courtesy of Argonne National Laboratory

 

The researchers’ design uses a solid electrolyte rather than a liquid electrolyte, forming a major distinction from lithium-ion (Li-ion) batteries. Critically, the lithium-air battery can store 1 kilowatt-hour per kilogram or higher, up to four times the energy density of Li-ion batteries. The design brings the potential to enable 1,000 miles of range on a single charge, addressing a critical barrier to mass EV adoption. According to the Department of Energy (DOE)’s Office of Energy Efficiency and Renewable Energy, the majority of all-electric vehicles can travel 100 to 400 miles on one charge. 

 

Lithium-air Batteries

Lithium-air batteries, which draw oxygen from the surrounding air, avoid the safety concerns and raw material supply risks seen in their Li-ion counterparts. They could be a game-changer for the EV industry as companies explore alternatives offering higher performance with lower production costs. In addition to consumer-facing EVs, the researchers’ design could also power domestic airplanes, trains, long-haul trucks, and even submarines. 

The research—funded by the DOE’s Office of Basic Energy Sciences and Vehicle Technologies Office—was recently published in Science.

 

An electric vehicle that could drive 1,000 miles on a charge? Scientists @illinoistech & @argonne have developed a lithium-air battery that could make it possible. It could be safer than today's li-ion batteries and have as much as 4X the energy density: https://t.co/gwAHk0Pb5n pic.twitter.com/JbT141jUsi

— DOE Office of Science (@doescience) February 28, 2023

 

Argonne’s press release touts the design as the first lithium-air battery to achieve a four-electron reaction at room temperature. Comprising a ceramic polymer material and producing lithium oxide upon discharge, the design underwent several testing techniques, including transmission electron microscopy at Argonne’s Center for Nanoscale Materials in Illinois. The researchers also operated a test cell for 1,000 cycles to prove its stability over repeated charge and discharge rounds. 

 

Argonne National Laboratory’s Center for Nanoscale Materials in Illinois. Image used courtesy of the Department of Energy

 

With further development, the researchers expect future design iterations to reach a record 1,200 watt-hours per kilogram of energy density—nearly four times that of Li-ion batteries. Mohammad Asadi, one of the paper’s authors and an assistant professor of chemical engineering at Illinois Tech, mentioned in a news release that since a solid-state electrolyte contributes around 75% of the total energy density, there’s an opportunity to minimize thickness without sacrificing performance—thus yielding a higher energy density. 

 

The Race to Develop Better EV Batteries

Battery manufacturers and EV makers are aggressively pushing for batteries with a higher range, fewer safety issues, and lower costs than the Li-ion status quo. 

Still, each year, EV models are achieving higher ranges than ever. From 2011 to 2021, the median range for EVs sold in the U.S. increased from 68 miles to 234 miles, while the maximum EV range quadrupled to 405 miles on a single charge, according to the DOE. Fourteen light-duty EV models introduced in 2022 could reach a range of 300 miles or more. But technical limitations and volatile supply chains impede lithium-ion batteries from growing at the same scale as in the last decade. 

Some alternatives explored today include lithium-sulfur batteries, some of which could provide around 1,000 miles of range. They’re generally cheaper, lighter, and can store more energy than other battery types. 

Another alternative is solid-state lithium-metal batteries, offering superior performance and the ability to store substantially more energy than Li-ion batteries. They could provide 500 to 600 miles or more of range. 

Meanwhile, sodium-ion batteries are a promising but still-nascent breed with little commercial traction for auto applications. They’re made with abundant and cheap materials that avoid the many challenges of sourcing raw materials for Li-ion production.