| Lithium-ion batteries have become attractive energy storage systems for portable electronic devices as they offer higher energy density compared to other rechargeable systems. The most widely used commercial cathode material for lithium-ion batteries is LiCoO2 due to its ease of synthesis, stable electrochemical cycling, high reversibility and long cycle life. However, the relatively high cost and toxicity of cobalt stimulated researchers to search for cheaper and safer alternative cathode materials which have either comparable or better electrochemical performance than LiCoO2. In this paper, novel cathode materials with excellent electrochemical performance were obtained by anion-cation compound substitution at the base of Li(Ni1/3Co1/3Mn1/3)O2, which was attractive all around the world. Despite the positive effect of Li(Ni1/3Co1/3Mn1/3)O2 for the electrochemical property , the delivered capacities have shown a capacity fading of long-term cycling.In order to overcome the problem, we optimized the best synthesis techniques of Li(Ni1/3Co1/3Mn1/3)O2, and investigated the influence of anion-cation compound substitution on the properties of the as-prepared samples.In this work, layered Li(Ni1/3Co1/3Mn1/3)O2 powders were successfully synthesized from the sol-gel method. The effects of synthetic condition on the structural and electrochemical properties of the samples was characterized by Flourier-Infrared spectra(FT-IR), X-ray diffraction(XRD), atomic absorption spectra(AAS) and electrochemical experiments. The results got from the experiments showed that the samples of Li(Ni1/3Co1/3Mn1/3)O2 which were sintered for 18h at 900℃from Li/M=1.1:1 were best. Li(Ni1/3Co1/3Mn1/3)O2 exhibited a discharge capacity of 162mAh/g in the voltage range of 3.0 4.3V, the capacity retention at the 10th cycle is 92.0%.In order to improve structural stability and cycling performance of Li(Ni1/3Co1/3Mn1/3)O2, we introduced Mg, Al and F into Li(Ni1/3Co1/3Mn1/3)O2 lattice. The results showed that Mg-Al co-substitution could reduce cation-mixing and cycling performance had improved. However, the occupancy of the Mg(2+ and Al3+ ions in the Li-layer decreased the deintercalation amount of Li+ ion from layered structure, therefore, the initial capacity of the Mg-Al co-doped materials decreased(153mAh/g). For Al-F co-substituted samples, a small amount of Al...
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