Preparation of high tap-density Li ₄Ti ₅O ₁₂ anode material with two-step calcination process

Li ₄Ti ₅O ₁₂ anode materials were prepared by solid-state reactions with two-step calcination process using Li ₂CO ₃ and nano-TiO ₂ as raw materials. The effects of ball-milling process and milling time on the performance of Li ₄Ti ₅O ₁₂ were investigated. The physical properties and electrochemical performance of Li ₄Ti ₅O ₁₂ were characterized by XRD, SEM, tap density dosimeter, charge-discharge tester and electrochemical workstation, respectively. The results show that ball-milling process can enhance the purity of products and obviously improve the tap-density and electrochemical properties of Li ₄Ti ₅O ₁₂. When the milling time is 2 h, the tap-density of Li ₄Ti ₅O ₁₂ is 1.70 g/cm ³. The initial discharge specific capacity at a current density of 0.1C is 174 mA·h/g, and 124.9 mA·h/g at 5C.