Enhanced Interfacial Stability of Mn-Based Cation-Disordered Rocksalt Li1.2Cr0.3Ti0.3Mn0.3O1.9F0.1 Cathodes via an Ion-Conductive LAGP Glass Ceramic Coating

Mn-based disordered rock-salt (DRX) cathode materials offer high theoretical capacities and operating voltages, rendering them promising candidates for high-energy-density lithium-ion batteries. However, severe interfacial reactions between Mn-based DRX cathodes and the electrolyte can induce surface degradation and a pronounced increase in interfacial impedance. In this study, a LAGP glass ceramic coating layer was introduced onto the surface of Li1.2Cr0.3Ti0.3Mn0.3O1.9F0.1 (LCTMOF) particles to minimize direct contact between the active material and the electrolyte, thereby enhancing the capacity retention over 50 cycles. It delivered an initial discharge capacity of 278.7 mAh g−1 and retained 227.3 mAh g−1 after 50 cycles. Relative to the pristine uncoated cathode, the LAGP glass ceramic coating material achieved a capacity retention of 81.5% together with improved rate performance, retaining a high specific capacity of 184.5 mAh g−1 at a current density of 500 mA g−1. Surface XPS analysis, together with the electrochemical results, suggests that the LAGP glass ceramic coating mitigates cathode interfacial degradation under the investigated cycling conditions.