Charged EVs | PNNL researchers study common lithium salt for cheaper and quicker battery manufacturing

Scientists at the US Department of Energy‘s Pacific Northwest National Laboratory (PNNL) have recently discovered that the sublimation of lithium oxide, when mixed with nickel-rich cathode precursors, creates a single-crystal structure that could be used in longer-lasting batteries.

In a new finding published in Nature Energy, the PNNL-led team showed that vapor from lithium oxide (Li2O) sublimation—the process whereby a solid turns directly into a vapor—accelerates a chemical reaction that forms single crystals when mixed with nickel-rich precursors. The sublimation happens at just one atmosphere of pressure, the everyday pressure felt at sea level. Single-crystal battery materials are thought to help batteries last longer and could help decrease the cost of battery manufacturing.

“The discovery offers a potentially faster, more efficient, and cheaper way to scale up the manufacturing of nickel-rich lithium-ion batteries,” said Jie Xiao, co-author on the paper and a Battelle Fellow who holds a joint appointment with PNNL and the University of Washington. At UW, Xiao is the university’s Boeing Martin Professor in the Mechanical Engineering Department. “The research shows us how materials science can be applied to simplify the manufacturing process,” Xiao continued.

Nickel-rich lithium cathode material tends to form as agglomerations known as “polycrystals.” Boundaries between the crystals become weaker as the battery discharges and charges. Over time, these weaknesses lead to cracking, which degrades the battery and shortens its lifetime.

“You can imagine all those tiny particles are agglomerated together, and they get pushed and pulled as the battery charges and discharges,” Xiao said. “The movement can create cracks, which weakens the battery.”

“Single-crystal cathodes don’t have the vulnerabilities that arise from polycrystal structures,” Xiao said. “So, we hope single crystals will mitigate and eventually eliminate all the big challenges in nickel-rich cathode materials.”

However, the team has more work to do before any batteries can be produced, Xiao said. Because Li2O is not broadly used for materials synthesis, the cost to use it commercially is currently too high. However, Xiao noted that Li₂O is easily produced by processing other lithium salts, such as lithium hydroxide (LiOH).

Xiao and her team are now working with industry partners to scale up the process while maintaining lower manufacturing costs and aim to provide single crystals to their strategic partners in 2026.

Source: Pacific Northwest National Laboratory