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.