An improved solid-state reaction to synthesize Zr-doped Li4Ti5O12 anode material and its application in LiMn2O4/Li4Ti5O12 full-cell

Li4Ti5−xZrxO12 (x=0, 0.05, 0.10, 0.15, 0.20) anode materials with uniform particle size distribution have been synthesized by an improved solid-state reaction. The mixture of TiO2, ZrO2, Li2CO3 and phenolic resin is activated by high energy ball milling at room temperature first. The XRD analyses reveal that appropriate amount of Zr4+ can enter into the lattice structure of Li4Ti5O12 which leads to slightly increased lattice parameters. The electrochemical performance is evaluated by galvanostatic charge/discharge tests and the results demonstrate that minute amount of Zr4+ (x=0.05) can enhance the rate capability of Li4Ti5O12 significantly, although the cycling performance remains the same. Specifically, Li4Ti4.95Zr0.05O12 can still delivers 112.8 mAh g−1 at 10 C rates, while it is 95.6 mAh g−1 for the undoped sample. In addition, EIS results prove that the charge transfer resistance of Li4Ti5O12 is reduced by employing Zr4+ as dopant. Furthermore, the LiMn2O4/Li4Ti5O12 full-cell also exhibits excellent electrochemical performance.