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A rod-like Li-rich manganese layered oxide cathode material Li1.2Mn0.54Ni0.13Co0.13O2 is synthesized through β-MnO2 template by a simple solid-state reaction, and the reacting process and electrochemical properties are studied. The results show that the radial nanometer effect and inherent structural stability of β-MnO2 nanorods bring about fast chemical reaction, morphologic heredity and service toleration. The unique architecture of the rod-like Li1.2Mn0.54Ni0.13Co0.13O2 also results in superior layered structure with low cation mixing and excellent electrochemical performances. The initial discharge capacity is about 250 mAh g−1 and the capacity retention rate is about 76.0% after 80 cycles at 0.1 C current rate. When cycled at 2 C rate, the discharge capacity is as high as 175.3 mAh g−1, suggesting a good rate capability. The capacity decline is mainly attributed to the radial direction nanometer effect, structural transformation, cation mixing and surface degradation.

LiNi0.6Mn0.2Co0.2O2 is considered as a promising Ni-rich layered cathode material of lithium-ion batteries due to low cost and high capacity. However, it is generally prepared by complicated precursor methods. In this work, LiNi0.6Mn0.2Co0.2O2 is synthesized by a solid-state method with manganese acetate as manganese source and an effective mixing way. The as-prepared samples are characterized by XRD, FESEM, XPS and electrochemical techniques. The results show that the synthesized LiNi0.6Mn0.2Co0.2O2 cathode materials have an α-NaFeO2 type structure with insignificant cation mixing, octahedral single crystal and quasi sphere morphology, smaller particle size and good dispersion, so that it displays an initial discharge capacity of 163.6 mAh g−1 with a coulombic efficiency of 85.6% at 0.1C, a capacity retention of 99.1% after 100 cycles at 0.5C and an excellent rate performance, and also an initial discharge capacity of 177.3 mAh g−1 with capacity retention of 94.6% after 155 cycles at 55 °C.