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). 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