Crystal structure and electrochemical performance of lithium-rich cathode materials xLi₂MnO₃· (1-x)LiNi_0.5Mn_0.5O₂ (x=0.1-0.8)

A series of lithium-rich cathode materials, xLi₂MnO₃·(1-x)LiNi_0.5Mn_0.5O₂ (x=0.1-0.8), were successfully synthesized by a sol-gel method. X-ray diffraction, scanning electron microscopy, and electrochemical tests were used to investigate the crystal structure, morphology, and electrochemical performance of the as-synthesized materials, respectively. The results showed that the materials with higher Li2MnO3 content had higher initial discharge capacity but poorer cycle stability, while the materials with lower Li₂MnO₃ content showed lower discharge capacity but better cycle stability, and the spinel impurity phase was also found. Based on the data, the optimal electrochemical properties were obtained when x=0.5 in xLi₂MnO₃· (1-x)LiNi_0.5Mn_0.5O₂. Moreover, the electrochemical properties were also worthy of attention when x=0.4, 0.6.