Electrolytes Towards High Voltage Mn-Rich Cathodes

Earth-abundant, sustainable Mn based cathode materials become an attractive option due to the arising concerns of safety, cost, and material availability. Among this class, the Li-rich, Mn-rich (LMR) layered-structure cathode materials show promise due to their high galvanometric energy density. However, the challenge of Mn dissolution/deposition persists, posing a significant hurdle to the long-term performance of LMR cathodes and playing a crucial role in the capacity fade of LMR. In this presentation, the electrolyte design to mitigate Mn dissolution will be discussed. Through the removal of highly solvating solvents like ethylene carbonate (EC) and the introduction of low-solvating solvents, it becomes possible to effectively prevent Mn dissolution, leading to significantly improved cyclability. Ion chromatography and ICP-MS were employed to analyze the amount of dissolved Mn in the electrolyte and its deposition on the anode.