Increasing awareness of the environment leads to a goal of replacing the internal combustion engine with an electrical motor. Lithium-ion batteries (LIBs) become vital energy-storage devices in electric vehicles (EVs). Li4Ti5O12 (LTO) is a promising material of LIB because of it high-rate capability, cyclability, and safety, as comparing to the graphite-based anode materials in commercial LIBs. These superior characteristics are required for EV applications. However, one of the major concerns in LTO-based LIBs is gassing at elevated temperature. Carbon coating on LTO has been proposed to mitigate the gassing by prevention of interface reactions between LTO and organic electrolyte solutions. In this work, the LTO is coated with carbon using one of our previous reported method: the “modified -Reaction at Autogenic Pressure and Elevated Temperature (m-RAPET) process for three different process durations which allows carbon coatings with different coverage and thickness on LTO surface. The m-RAPET LTO for the process duration of 3 hours (LTO/C-3h) showed better electrochemical performance in comparison with the commercially available carbon coated LTO (cLTO/C) and commercial LTO (cLTO). These materials give us the classification of gassing study based on the type of surface modification. The classified surfaces are as follows: Pristine(cLTO), Partial carbon coating (cLTO/C and LTO/C-1h) and Fully carbon coated (LTO/C-2h and LTO/C-3h). The gassing behaviours among the LTO/C, cLTO/C, and cLTO samples were investigated at elevated temperatures using commercial operando gas analysis testing cell (PAT-Cell-Gas EL-CELL) (facilitates in-situ pressure and temperature measurements) in different states of charge (SoC) and environment conditions to understand the fundamental gassing phenomenon of LTO-based LIBs. operando gas analysis showed that the Partial carbon coatings on LTO facilitates the gassing instead of suppressing it. The gassing can be considerably reduced by completely carbon coating on LTO where the gassing is not completely mitigated. But with the proper surface modification and use of electrolyte with the additives the gassing can be mitigated in LTO based LIBs, allows us to use LTO based LIBs in EVs even at elevated temperatures.

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