Insights from Ab\nInitio Molecular Dynamics on the\nInterface Reaction between Electrolyte and Li<sub>2</sub>MnO<sub>3</sub> Cathode during the Charging Process

The complex interface reactions are crucial to the performance\nof the Li<sub>2</sub>MnO<sub>3</sub> cathode material. Here, the interface\nreactions between the liquid electrolyte and the typical surfaces\nof Li<sub>2</sub>MnO<sub>3</sub> during the charging process are systematically\ninvestigated by ab initio molecular dynamics (AIMD) simulation and\nfirst-principles calculation. The results indicate that these interface\nreactions lead to the formation of hydroxide radicals, oxygen, carbon\ndioxide, carbonate radicals, and other products, which are consistent\nwith the experimental findings. These processes primarily result from\nthe conversion of the stable closed-shell O<sup>2–</sup> into\nreactive oxygen ions by electron loss. All surfaces exhibit some degree\nof layered- and spinel-like phase transitions during the AIMD simulations,\nconsistent with the experiment. This is mainly attributed to the decrease\nin the Mn–O bond strength and the increase in the Li/O ion\nvacancy concentration. This study offers valuable theoretical insights\ninto the interface reaction between lithium-rich cathode materials\nand liquid electrolytes.