On the Safety of the Li4Ti5O12 ∕ LiMn2O4 Lithium-Ion Battery System

Abstract

The aim of this work is to investigate the inherent safety characteristics of the cell chemistry in a real battery. For this purpose, the reactivity of the anode material with the electrolyte was first studied upon its electrochemical lithiation in a Li-metal half-cell. Results obtained by differential scanning calorimetry show that the total heat associated with this reaction increased when the lithium amount inserted in increased, with no noticeable change in the onset temperature . It was also found that the total heat of the fully lithiated was much smaller compared to that of the fully lithiated graphite , the latter having a lower onset temperature . The thermal and structural stability of and phases was investigated after the chemical lithiation of with butylithium and the chemical delithiation of with nitronium tetrafluoroborate. Data from thermal gravimetric analysis show that the cathode released less than oxygen below , while the anode gained at the same temperature. The accelerated rate calorimetry test performed on 18650-cells containing chemistry showed no thermal runaway, explosion, or fire. These results clearly demonstrate that the battery could be one of the safest Li-ion battery systems.