Hollow microspherical layered xLi₂MnO₃·(1-x)LiNiO₂ (x=0.3–0.7) as cathode material for lithium–ion batteries

Li-rich layered Li₂MnO₃ is of great attraction for high energy lithium ion batteries. However, its cycling is still needed for improvements. Here we report a hollow microsphere-structured xLi₂MnO₃·(1-x)LiNiO₂ (x = 0.3–0.7) that is synthesized by using in-situ template-sacrificial strategy. Powder X-ray diffraction (XRD) and scanning electron microscope (SEM) characterizations prove that the xLi₂MnO₃·(1-x)LiNiO₂ (x = 0.3–0.7) are based on monoclinic Li₂MnO₃ with α-NaFeO₂ layered structure in which Li⁺ ions are orderly arranged in the transition metal layers, and the hollow-microspheres have diameters of ∼3 μm. Electrochemical results show that the optimal ratio of Li₂MnO₃/LiNiO₂ is 0.6/0.4. As a consequence, the stabilized discharge capacity of 0.6Li₂MnO₃·0.4LiNiO₂ (0.6LLMNO) is ∼210 mAh g⁻¹ after the first few cycles. This shows that appropriate amount Ni substitution for Mn in Li₂MnO₃ helps to improve the specific capacity and cycling stability.