Effect of different MnO₂ precursors on the electrochemical properties of spinel LiNi_0.5Mn_1.5O₄ cathode active materials for high-voltage lithium ion batteries

Highlights: • Synthesis of spinel LNMO via a facile template method. • The specific morphology of LNMO is closely related to that of MnO₂ precursor. • LNMO using NH₄HCO₃ as precipitant exhibits superior electrochemical performance. - Abstract: LiNi_0.5Mn_1.5O₄ (LNMO) cathode materials with different morphologies are prepared via a facile template method using various MnO₂ precursors. The structures, morphologies and electrochemical properties of the as-prepared LiNi_0.5Mn_1.5O₄ samples are tested by various physical and electrochemical methods. The results of characterization show that the spinel LNMO cathode materials have good crystal structure and the MnO₂ precursors have no effect on the final products. Moreover, the specific morphology of LNMO is closely related to that of MnO₂ precursor, and further influence the electrochemical performance. In addition, the LNMO sample using NH₄HCO₃ as precipitant exhibits excellent rate capability and cyclic stability in all as-prepared samples. Cycled at 0.5 and 1 C, the discharge capacities of LNMO cathode active particles using NH₄HCO₃ as precipitant are 110.6 and 102.2 after 200 charge–discharge cycles, respectively, which are the largest compared with the LNMO using (NH₄)₂S₂O₈ and KMnO₄ as oxidants.