Anode materials based on silicon, tin, titanium oxides and lithium titanate, as well as their composites with carbon for lithium-ion batteries are reviewed. A large change in volume upon lithium intercalation-deintercalation results in fast degradation of anode materials based on silicon and tin. Formation of nanocomposites with carbon allows to stabilize these materials and their cycling performance. The processes of carbon coating formation are considered in more detail for lithium titanate, a promising anode material, as an example. In this case, carbon ensures acceleration of diffusion across the grain boundaries. The effect of the temperature treatment and the carbon precursor on the formation and electrochemical properties of a composite material based on Li4Ti5O12 and carbon is considered. It is shown that the size of Li4Ti5O12 particles can be controlled by the amount of the carbon precursor and the calcination temperature. The combination of data of X-ray powder diffraction, thermogravimetry, Raman spectroscopy, and electrochemical testing shows that formation of a conductive carbon coating requires preliminary sample heating in air at temperatures no lower than 400 œC followed by calcination in an inert atmosphere. |
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