LG Energy Solution has taken a significant step toward commercializing lithium manganese-rich (LMR) batteries for electric vehicles by identifying the mechanisms behind gas generation and capacity degradation in the next-generation battery technology.
The company said on Sept. 7 that its researchers, working with a team led by Professor Jong-Woo Lim of Seoul National University’s Department of Chemistry, have developed operating and manufacturing conditions that improve the stability of large-format LMR cells.
The findings were published in Nature Communications, a globally recognized international scientific journal, underscoring both the technological significance and academic value of the research.
LMR batteries have emerged as a promising next-generation battery technology because they can reduce dependence on expensive cobalt while using relatively inexpensive manganese as a major cathode material. Unlike conventional cathode materials that primarily rely on transition-metal redox reactions, LMR materials can also utilize oxygen within the cathode structure to store energy, potentially enabling high energy density while reducing material costs.
The technology, however, has faced a major obstacle in its path toward commercialization.
During charging, oxygen inside an LMR cathode can become oxidized. If the oxidized oxygen is not sufficiently restored during subsequent discharge, irreversible structural changes can occur within the cathode. This can lead to gas generation, capacity degradation and deterioration in battery performance.
The problem becomes particularly serious in large-format EV cells. Unlike small laboratory cells, automotive batteries have limited internal free volume, meaning that accumulated gas can increase internal pressure and accelerate performance degradation.
The research team focused on the reversibility of oxygen during repeated charge and discharge cycles to determine how the problem could be controlled.
Their analysis showed that oxygen recovery is influenced not only by the upper charging voltage but also by the lower discharge voltage. This finding suggests that both ends of the operating voltage range need to be carefully controlled to improve the long-term stability of LMR batteries.
In experiments, lowering the upper charging voltage from 4.6 volts to 4.3 volts increased the reduction rate of oxidized oxygen from 86% to 97%. The researchers also found that when the battery was discharged to 2.0 volts, rather than the conventional 3.0 volts, oxygen was restored to a state close to its original condition.
The findings allowed LG Energy Solution researchers to redesign the operating voltage range and formation process for 40Ah-class large-format LMR cells.
In particular, the company introduced a lower-temperature process during the formation stage, which is a critical step in battery manufacturing, to suppress gas generation associated with large-format cells.
The optimized cells demonstrated improved durability in testing. After 883 charge-discharge cycles, the 40Ah-class LMR cells retained 92.2% of their initial energy.
The result is significant because it demonstrates the potential of LMR technology beyond small-scale laboratory cells and at the large-cell level required for practical EV applications.
LMR has attracted growing attention across the battery industry as automakers and battery manufacturers seek technologies capable of combining competitive costs with high energy density. Its reduced reliance on cobalt and greater use of manganese could provide an advantage as the EV industry faces increasing pressure to lower battery costs.
The latest research also highlights how competition in LMR technology is expanding beyond cathode material composition. Cell design, voltage-control strategies and manufacturing processes are increasingly becoming critical factors in determining whether the technology can meet the durability and safety requirements of electric vehicles.
Professor Lim said the research identified the underlying cause of LMR degradation from the perspective of oxygen reversibility and demonstrated that cell stability can be improved through the design of electrochemical protocols.
He emphasized that securing long-term LMR stability requires consideration of discharge conditions as well as charging conditions.
LG Energy Solution said the research demonstrates that gas generation, one of the major challenges facing LMR commercialization, can be effectively suppressed while maintaining stable battery life in large-format cells.
The company added that the findings provide an important foundation for accelerating its growth in the next-generation LMR battery market.
With the battery industry increasingly searching for alternatives that can deliver high energy density at lower costs, LG Energy Solution's ability to demonstrate improved performance in a 40Ah-class large cell could strengthen the commercial prospects of LMR technology for future electric vehicles.
