Electrochemical properties of 0.6Li[Li1/3Mn2/3]O2-0.4LiNixMnyCo1−x−yO2 cathode materials for lithium-ion batteries

► Li-rich solid solutions have been synthesized by a solid-state reaction method. ► Li1.2Ni0.18Mn0.58Co0.04O2 and Li1.2Ni0.2Mn0.52Co0.08O2 are firstly reported. ► The higher Ni content is, the higher cation mixing is, and the lower resistance is. ► Cation mixing influences capacity, while resistance affects rate capability.