Effect of Temperature on Li-rich Layered Cathode Material 0.5Li₂MnO₃·0.5LiNi_0.5Mn_0.5O₂ Prepared by a Low Temperature Solution Combustion Synthesis

摘要

Li-rich layered cathode materials of 0.5Li2MnO3·0.5LiNi0.5Mn0.5O2 were synthesized by a lowtemperature solution combustion synthesis method. The effects of different ignition temperatures onthe phase composition and electrochemical performances of the materials were studied. The resultsreveal that all the materials of 0.5Li2MnO3·0.5LiNi0.5Mn0.5O2 are of ordered layered structure andmaintain a similar morphology with homogeneous and polyhedral particles. Electrochemicalexperiments indicated that the 0.5Li2MnO3·0.5LiNi0.5Mn0.5O2 obtained at a ignition temperature of500 °C showed the higher discharge capacity of 220.2 mAh·g-1 at 0.1 C and the capacity retention ratesof 91.1 % after 50 cycles as well as excellent rate capability than that of other samples. The capacityretention rates of the samples ignited at 400 °C, 500 °C and 600 °C are more than 90%, and the sampleignited at 400 °C shows the best electrochemical cycling stability during cycling. It is concluded thatignition temperature has an important effect on the electrochemical performances of Li-rich layeredcathode materials of 0.5Li2MnO3·0.5LiNi0.5Mn0.5O2.