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Layered FTO-coated Li[Li0.2Co0.13Ni0.13Mn0.54]O2 (FTO-LRMO) nanoparticles were synthesized by a simple polymer-pyrolysis method and then coated with F0.3–SnO2 (FTO) to form a conductive protection layer. The FTO-LRMO electrode demonstrates a high initial columbic efficiency of 88%, a large reversible capacity of ∼296 mA h g−1, and an excellent cyclability with 83% capacity retention after 300 cycles. Particularly, this material can deliver a quite high capacity of 164 mA h g−1 at a high rate of 2400 mA g−1, exhibiting excellent rate capability. This superior electrochemical performance results from the conducting functionalized surface modification, which not only offers an effective protection layer to form a stable SEI film and maintain the stability of the interface structure, but also decreases the interface and reaction impedance by the conductive coating. Therefore, the conducting functionalized coating by FTO is a simple, effective and novel way to enhance the electrochemical performance of lithium-rich Mn-based oxide cathodes for practical battery applications. [ABSTRACT FROM AUTHOR]

Abstract: LiCo1−x Mg x O2(x=0, 0.01, 0.03, and 0.05) was synthesized by a polymer-pyrolysis method. The effect of Mg doping on the structure and electrochemical properties of LiCoO2 was investigated. XRD analysis showed that all the samples obtained had the well-ordered layer structure. SEM image showed that the powders consist of well-crystallized particles with hexagonal form. The charge–discharge tests showed that the increase of Mg content in LiCoO2 pronouncedly improved the cycling performance of samples although it slightly decreased the initial discharge capacity. LiCo0.97Mg0.03O2 demonstrated an initial discharge capacity of 169.2mAhg−1 and the best cyclic performance as it retained 91.1% of the initial capacity after 50 cycles when cycled at 50mAg−1 between 3.0 and 4.5V. Cyclic voltammagram demonstrated that the Mg doping can distinctly stabilize the crystal structure of LiCoO2 by suppressing the phase transition of the cathode during lithium ion deintercalation and intercalation. [Copyright &y& Elsevier]