Sn embedded Li4Ti5O12/C composite as a high capacity anode material for li-ion battery

Abstract

Sn embedded Li4Ti5O12/C composite (C-Sn/Li4Ti5O12) was prepared using TiO2 sphere as precursor. The physical characteristics of C-Sn/Li4Ti5O12 were characterized by X-ray diffraction (XRD), thermogravimetric analysis (TG), Raman spectra, elemental analysis, scanning election microscopy (SEM) and transmission electron microscopy (TEM). The electrochemical performances were investigated by cyclic voltamnograms (CVs) and galvanostatic charge-discharge tests. These analyses indicate that C-Sn/Li4Ti5O12 was spherical-like particles about 1μm. Moreover, it was composed of inner spinel Li4Ti5O12, outer-coated carbon layer and Sn embedded between inner Li4Ti5O12 and outer carbon layer. Combining high specific capacity of Sn particles and high electronic conductive of carbon coated layer, as-prepared C-Sn/Li4Ti5O12 shows improved discharge capacity. Compared with carbon-coated Li4Ti5O12 (C-Li4Ti5O12), the C-Sn/Li4Ti5O12 exhibited better capability at 200 mA g-1 with a discharge capacity increased by ~ 16.3%. After 100 cycles, the discharge capacity of C-Sn/Li4Ti5O12 was stable at ~ 242 mAh g-1.