SNU professor finds key to improving stability of LMR EV batteries
LG Energy Solution's LMR battery on display at InterBattery 2026, held in Seoul, from March 11 to 13 / Courtesy of LG Energy Solution
Seoul National University professor Lim Jong-woo, in collaboration with LG Energy Solution, has identified a key factor behind gas generation and capacity loss in lithium-manganese-rich (LMR) batteries, advancing efforts to apply the next-generation battery technology to large-format cells for electric vehicles (EVs).
Lim Jong-woo, a chemistry professor at Seoul National University / Courtesy of LG Energy Solution
The chemistry professor’s research team and the battery maker found that controlling oxygen reversibility during charging and discharging could improve the stability of large-format LMR battery cells.
LMR is a promising next-generation cathode material that uses abundant, low-cost manganese and can deliver high energy density through oxygen redox alongside transition-metal redox.
However, the oxygen inside the cathode can fail to fully return to its original chemical state as the battery is repeatedly charged and discharged.
This can damage the battery’s internal structure and cause gas to build up, creating a particular challenge for large-format EV cells, which have less room to accommodate the resulting pressure.
The research team analyzed oxygen redox behavior under different charging and discharging conditions and found that oxygen recovery depended on both the upper cutoff voltage during charging and the lower cutoff voltage during discharge.
When the upper charging voltage was lowered to 4.3 volts from 4.6 volts, the reduction of oxidized oxygen increased to 97 percent from 86 percent. The researchers also found that lowering the discharge cutoff voltage to 2 volts from 3 volts allowed the oxygen to recover to nearly its original state.
“This study identified the causes of degradation of LMR batteries from the perspective of oxygen reversibility and showed that cell stability can be improved only through the design of electrochemical protocols,” Lim said.
“We confirmed that long-term stability of LMR batteries can be secured only by comprehensively considering not only charging conditions but also discharging conditions.”
Based on these findings, LG Energy Solution researchers redesigned the operating voltage range and formation process for 40-Ah-class large-format LMR cells. They also introduced a lower temperature formation process to suppress gas generation.
The optimized cells retained 92.2 percent of their initial energy after 883 charge-discharge cycles, demonstrating strong cycle-life stability in large-format cells designed for potential EV applications.
The findings were published in Nature Communications, an international peer-reviewed scientific journal.
An LG Energy Solution official said the research showed that stable battery life could be secured in large-format cells by effectively suppressing gas generation, calling it “an important foundation for accelerating growth in the next-generation LMR battery market.”
“This research demonstrates that gas generation, one of the key challenges facing LMR batteries, can be effectively suppressed to ensure stable battery life even in large-format cells,” an official from LG Energy Solution said. “It provides an important foundation for accelerating growth in the next-generation LMR battery market.”