A designed core-shell structural composite of lithium terephthalate coating on Li4Ti5O12 as anode for lithium ion batteries

A core-shell structural composite was synthesized with lithium terephthalate(Li_2C_8H_4O_4) coated on spinel Li_4Ti_5O_(12)(LTO). The composite displays a capacity of about 200 mA h g~(-1) and a good rate capability with two charge/discharge platforms at ~ 1.55 and ~ 0.8 V. The excellent cycling performance of the composite is attributed to the successful combination of high cycling stability of LTO and high specific capacity of Li_2C_8H_4O_4. In addition, an interesting phenomena is observed for the first time for this composite which is that lithium ions transfer between LTO and Li_2C_8H_4O_4 at a fast speed. This is investigated in details via the asymmetric charge/discharge measurement and cyclic voltammogram(CV).The LTO/Li_2C_8H_4O_4 composite may have potential applications to be used as an anode material for the electric vehicle batteries, which is shallowly charged/discharged at ordinary times using the charge/discharge platform of LTO and fully charged/discharged at emergency to release the extra high capacity from Li_2C_8H_4O_4.