Enhanced electrochemical performance of Li_4Ti_5O_(12)/carbon nanotubes/glucose composite as anode material for lithium ion batteries

摘要

Li4Ti5O12 (LTO)/carbon nanotubes (CNTs)/glucose (g) composite is synthesized via solid method followed by sonicating. The influences of carbon nanotubes and glucose additives on the microstructure and electrochemical performances of LTO are investigated. As-prepared LTO composited with 2.5wt% CNTs and 2wt% glucose (LTO/2.5CNTs/2g) exhibits excellent electrochemical performances. On the one hand, LTO/2.5CNTs/2g composite shows well dispersed between LTO particles and CNTs with width of 200-400nm. On the other hand, with higher surface areas 45.8839m(2)g(-1) and pore volume of 0.2036mlg(-1), the discharge capacity of LTO/2.5CNTs/2g can reach 251.9 mAhg(-1) at 20mAg(-1), while its discharge capacity still reaches 119.3 mAhg(-1) at 2 Ag-1. Additionally, LTO/2.5CNTs/2g composite achieves initial discharge capacity of 173.2 mAhg(-1) at 1 Ag-1, stabilizing at 118.9mAhg(-1) after 1000 cycles. More importantly, its band gap is the least with Li+ diffusion coefficient 1.14x10(-11)cm(2) s(-1).