Effects of Synthesis Conditions of Na[sub.0.44]MnO[sub.2] Precursor on the Electrochemical Performance of Reduced Li[sub.2]MnO[sub.3] Cathode Materials for Lithium-Ion Batteries

Li[sub.2] MnO[sub.3] nanobelts have been synthesized via the molten salt method that used the Na[sub.0.44] MnO[sub.2] nanobelts as both the manganese source and precursor template in LiNO[sub.3] -LiCl eutectic molten salt. The electrochemical properties of Li[sub.2] MnO[sub.3] reduced via a low-temperature reduction process as cathode materials for lithium-ion batteries have been measured and compared. Particularly investigated in this work are the effects of the synthesis conditions, such as reaction temperature, molten salt contents, and reaction time on the morphology and particle size of the synthesized Na[sub.0.44] MnO[sub.2] precursor. Through repeated synthesis characterizations of the Na[sub.0.44] MnO[sub.2] precursor, and comparing the electrochemical properties of the reduced Li[sub.2] MnO[sub.3] nanobelts, the optimum conditions for the best electrochemical performance of the reduced Li[sub.2] MnO[sub.3] are determined to be a molten salt reaction temperature of 850 °C and a molten salt amount of 25 g. When charge–discharged at 0.1 C (1 C = 200 mAh g[sup.−1] ) with a voltage window between 2.0 and 4.8 V, the reduced Li[sub.2] MnO[sub.3] synthesized with reaction temperature of Na[sub.0.44] MnO[sub.2] precursor at 850 °C and molten salt amounts of 25 g exhibits the best rate performance and cycling performance. This work develops a new strategy to prepare manganese-based cathode materials with special morphology.