Structural and electrochemical properties of LiCoMnO4 doped with Mg, La, and F as a high-voltage cathode material for lithium ion batteries

This study characterizes the relationship between synthesis conditions using the coprecipitation method and the structural/electrochemical properties of LiCoMnO4. A cathode material, LiCoMnO4, prepared at pH 7.7 via coprecipitation and calcinated at 850 °C for 14 h achieved an initial discharge capacity of 114.6 mAh g−1 and a capacity retention rate of 71.3% after 20 cycles. To improve electrochemical performance, LiCoMnO4 was doped with La, Mg, and F elements. The results showed that the strong ionic bonds of fluorination (M‒F; M=Li, Co, and Mn) can suppress the phase decomposition and Li/Co ionic mixing during the redox process and increase structural stability. Thus, LiCoMnO4 doped with F demonstrated excellent electrochemical performance compared with that of the other dopants.