Gassing behavior of LiMn2O4/Li4Ti5O12 full cell with different electrolytes that stored at elevated temperature of 70 °C is investigated. Scanning electron microscope (SEM), Transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR) are used to study the solid electrolyte interphase (SEI) layer formed in battery formation and storage processes. The results suggest that the SEI film is formed as a consequence of intrinsic reaction between Li4Ti5O12 electrode and electrolyte solvents. A smooth SEI layer is formed on Li4Ti5O12 electrode with full coverage in propylene carbonate (PC) based electrolyte during lithium intercalation process while gradually dissolved with lithium extraction. Moreover, the gas specificities generated in the different electrolyte solvents are also determined by gas chromatography–mass spectrometer (GC–MS) analysis and the reaction mechanisms of LTO electrode with electrolyte solvents are proposed.