Pre‐activation and Defects Introduced via Citric Acid to Mitigate Capacity and Voltage Fading in Li‐rich Cathode

The application of Li‐rich and Mn‐based layered cathode materials is impeded by the discharge voltage decay and capacity fading upon cycling, despite their high specific capacity. Here, we combine pre‐activation and nanoscale defects modification of lithium rich and manganese based layered materials to mitigate the above two serious problems through improved anionic redox activity and Li + conductivity. The optimum constructed nanoscale defects rich cathode material delivers a reduced voltage fading rate of 1.27 mV per cycle compared to 3.7 mV per cycle for the pristine material after 200 cycles at 1 C rate. Moreover, the nanoscale defects rich material delivers a high specific discharge capacity of 173.1 mAh · g –1 with a high capacity retention of 99.5 % after 200 cycles at 1 C rate superior than the pristine material (89.3 mAh · g –1 and 53.4 %, respectively). This study highlights the reversibility of oxygen redox in electrochemical stability and effectiveness of nanoscale defects in stabilize voltage.