Enhanced Cycling Stability of Cation Disordered Rock-Salt Li_1.2Ti_0.4Mn_0.4O₂ Material by Surface Modification With...

Cation disordered rock-salt lithium-excess oxides are promising candidate cathode materials for next-generation electric vehicles due to their extra high capacities. However, one major issue for these materials is the distinct decline of discharge capacities during charge/discharge cycles. In this study, Al₂O₃ layers were coated on cation disordered Li_1.2Ti_0.4Mn_0.4O₂ (LTMO) using atomic layer deposition (ALD) method to optimize its electrochemical performance. The discharge capacity after 15 cycles increased from 228.1 to 266.7 mAh g^-1 for LTMO after coated with Al₂O₃ for 24 ALD cycles, and the corresponding capacity retention enhanced from 79.7 to 90.9%. The improved cycling stability of the coated sample was ascribed to the alleviation of oxygen release and the inhibition on the undesirable side reactions. Our work has provided a new possible solution to address some of the capacity fading issues related to the cation disordered rock-salt cathode materials.