Facile synthesis and electrochemical performance of ordered LiNi0.5Mn1.5O4 nanorods as a high power positive electrode for rechargeable Li-ion batteries

One-dimensional ordered LiNi_0.5Mn_1.5O₄ nanorods have been fabricated and investigated for use as a high power cathode in rechargeable Li-ion batteries. These highly crystalline nanorods, with an ordered spinel structure and diameters and lengths around 130 nm and 1.2 μm, respectively, were synthesized in two steps by using a hydrothermal reaction to produce β-MnO₂ nanorods followed by solid-state lithiation. Electrochemical analysis showed the superior performance of nanorods as a cathode in Li-ion half cells. The specific charge and discharge capacities were found to be 120 and 116 mAh g⁻¹ at a 0.5 C rate, and 114 and 111 mAh g⁻¹ at a 1 C rate between 3.5 and 5.0 V vs. Li⁺/Li. Moreover, the nanorods exhibit high power capability, maintaining capacities of 103 and 95 mAh g⁻¹ at specific currents of 732.5 and 1465 mA g⁻¹ (5 and 10 C rates), respectively.