Microstructural and electrical properties of Mg substituted Li4Ti5O12 synthesized by ceramic method.

In this paper the effect of magnesium (Mg) substitution in lithium (Li) site of spinel lithium titanate (Li4Ti5O12, LTO) based materials for anodes of Li-ion batteries (LIBs) is extensively studied. The anode materials based on the formula Li4-xMgxTi5O12(x=0 and 0.2) are synthesized using conventional ceramic route at 850° C for 16h. Their phase formation processes, crystal structures, morphology, elemental analysis, cation distribution and electrical properties were studied using XRD, SEM, EDX, FT-IR and CIS characterization techniques. The XRD studies revealed the exact structure of the material which belonged to cubic spinel structure as part of the space group Fd-3m. The morphological characteristics related to phase and grain size allocation were found using SEM and the grain size was found to be in the range 0.9-1.1 µm. The FT-IR results revealed the oxide lattice structure built of MO6 (M= Li, Mg and Ti) as tetrahedra and octahedra. The electrical impedance studies showed the material (Li3.8Mg0.2Ti5O12) to exhibit excellent conductivity which was found to be 3.8×10−5 S/cm at ambient temperature for frequency ranging from 20 Hz to 1MHz. [ABSTRACT FROM AUTHOR]