First-principles calculation for point defects in Li₂Ti₂O₄

Based on the first-principles method, we theoretically investigate the effect of point defects on the electrical properties of Li 2 Ti 2 O 4 . The single Li vacancy ( V Li ), Ti vacancy ( V Ti ), O vacancy ( V O ), Li antisite (Li Ti ) and Ti antisite (Ti Li ) are inserted into Li 2 Ti 2 O 4 , respectively. Calculated electronic structures indicate that defects have an obvious influence on the Ti–O hybridization near the Fermi level. This hybridization plays a major role in the charging and discharging operation, so various defects can alter batteries’ average voltages and energy densities. These results provide practical guidance to develop Li 2 Ti 2 O 4 used as batteries.