Electrochemical and Thermal Investigation of Li[sub 4∕3]Ti[sub 5∕3]O[sub 4] Spinel

We have studied the electrochemical and thermal properties of spinel as a promising anode material for lithium ion batteries. The spinel/rock-salt two-phase transition process was interpreted using a core-shell model, which provided a good explanation of the different area-specific impedance behaviors during the charge and discharge processes. The constant dE/dT during the spinel/rock-salt phase transition was calculated from the heat-flow profile by isothermal microcalorimeter results and found to be around . This very low and constant entropy change indicates that is a good anode material in terms of thermal stability. Also, we propose that there is a new phase generation when more than one lithium atom is inserted into . According to the discontinuity of dE/dT results, the order/disorder transition at the low-voltage region (around vs Li) occurs during further lithium insertion.