Posco Holdings and Korea University have developed a new manufacturing method that could improve the performance and lifespan of next-generation lithium-ion batteries by adjusting heat-treatment temperatures without changing the materials' chemical composition.
The research, conducted by a team led by Korea University materials science and engineering professor Park Hyeok-jun and Posco Holdings' N.EX.T Hub research institute, focuses on lithium-manganese-rich cathodes, a promising alternative for electric vehicles and energy storage systems.
LMR cathodes can store more energy than conventional materials by harnessing chemical reactions involving both metals and oxygen. However, their commercial use has been hindered by structural instability and gradual voltage loss during repeated charging and discharging.
The researchers found that the temperature used during the early stages of cathode production plays a critical role in determining the material's long-term performance.
By testing precursor materials at different temperatures while keeping subsequent manufacturing conditions unchanged, the team discovered that lower-temperature treatment helped maintain a more uniform distribution of metals inside the cathode.
Higher temperatures, by contrast, caused the metals to separate into uneven clusters, creating structural weaknesses that accelerated performance degradation.
The improved internal structure helped stabilize the cathode and reduce voltage loss during repeated charging cycles.
After 500 charge-discharge cycles, cathodes produced using lower-temperature treatment showed a voltage decline of 250 millivolts, compared with 358 millivolts for those treated at higher temperatures — a reduction of about 30 percent.
The findings suggest that manufacturers could improve LMR cathode durability by optimizing existing production processes, without introducing new materials or significantly changing their chemical composition.
The researchers said the approach could offer a practical route toward commercial production of high-capacity cathodes for electric vehicles and energy storage systems.
Supported by Posco Holdings and the National Research Foundation of Korea, the study was published in the scientific journal ACS Energy Letters on Oct. 19 and featured on its supplementary cover.
hyejin2@heraldcorp.com
