Improved electrochemical performance of Ag-modified Li4Ti 5O12 anode material in a broad voltage window

Abstract

Li4Ti5O12/Ag composites were synthesized by a solid-state method. The effect of Ag modification on the physical and electrochemical properties is discussed by the characterizations of X-ray diffraction, scanning electron microscopy, cyclic voltammetry, electrochemical impedance spectroscopy, cycling and rate tests. The lattice parameter of Li 4Ti5O12 with a low Ag content is almost not changed, but the lattice parameter becomes larger due to the high content of Ag. Li4Ti5O12/Ag material has a uniform particle size which is about 1 μm. Modification of appropriate Ag is beneficial to the reversible intercalation and deintercalation of Li+. Modification of Ag not only decreases the charge transfer resistance of Li4Ti 5O12 material, but also improves the diffusion coefficient of lithium ion. Li4Ti5O12/Ag (3 mass%) material has the lowest charge transfer resistance, the highest diffusion coefficient of lithium ion and the best rate cycling performance. © Indian Academy of Sciences.