LG Energy Solution and Seoul National University Resolve Gas Buildup in Cobalt-Free LMR Batteries

LG Energy Solution and researchers at Seoul National University have established a new electrochemical operating protocol that prevents gas buildup in lithium-manganese-rich (LMR) batteries, clearing the primary technical hurdle for commercializing the cobalt-free cells in electric vehicles. The findings, published September 7, 2026, in Nature Communications, demonstrate that adjusting the voltage limits during the charge and discharge cycles stops the internal oxygen reactions from degrading the battery structure. The development moves LMR technology from a laboratory concept to a viable candidate for large-format automotive cells.[1][2]

LMR cathodes have long been viewed as a highly desirable chemistry for the electric vehicle industry because they replace expensive cobalt with abundant manganese while maintaining high energy density. They achieve this by utilizing both transition metals and the oxygen within the cathode material to store energy. However, the technology has historically failed in large-format applications because the oxygen oxidized during charging does not fully return to its original state during discharge.[2][5]

That incomplete oxygen recovery causes structural damage and generates gas inside the cell. In the confined space of a large electric vehicle battery, the accumulated gas creates severe internal pressure, rapidly degrading performance and creating safety risks. Until now, this gas generation has blocked battery manufacturers from scaling LMR chemistry beyond small, experimental formats.[3][5]

The joint research team, led by Professor Jongwoo Lim of Seoul National University's Department of Chemistry, discovered that oxygen reversibility is dictated by both the upper charging threshold and the lower discharge limit. By lowering the upper charging voltage from the conventional 4.6 volts to 4.3 volts, the researchers increased the reduction rate of oxidized oxygen from 86 percent to 97 percent.[1][4]

Furthermore, the team found that extending the discharge cutoff voltage down to 2.0 volts, rather than the standard 3.0 volts, allowed the oxygen to return almost completely to its initial state. "This study identified the causes of degradation in LMR batteries from the perspective of oxygen reversibility and demonstrated that cell stability can be improved through electrochemical protocol design alone," Lim said in a statement on September 7.[2][4]

Applying these parameters, LG Energy Solution engineers redesigned the operating voltage range for a 40-ampere-hour (Ah) large-format LMR cell. The company also introduced a lower-temperature formation phase—the initial activation process during manufacturing—to further suppress the characteristic gas generation of large cells.[1][5]

The optimized 40Ah cells retained 92.2 percent of their initial energy capacity after 883 charge-discharge cycles. That retention rate proves that LMR chemistry can achieve the longevity required for automotive applications without relying on complex material modifications that drive up manufacturing costs.[2][5]

While the laboratory results are definitive, the transition from a 40Ah test cell to mass-produced battery packs capable of powering a two-ton vehicle remains a substantial engineering challenge. An LG Energy Solution spokesperson noted that the research "provides an important foundation for growth in the next-generation LMR battery market," though the company has not yet announced a timeline for integrating the cells into commercial electric vehicle platforms. Automakers will need to validate the modified voltage protocols within their existing battery management systems before the cobalt-free cells reach consumer driveways.[3][4]