Facile synthesis of nanostructured Li4Ti5O12/PEDOT:PSS composite as anode material for lithium-ion batteries

Abstract

A poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) coated Li₄Ti₅O₁₂ (LTO/PP) composite is synthesized by a facile and convenient approach, which involves dispersing LTO in an aqueous solution of PEDOT:PSS, followed by rotary evaporation accompanied by an ultrasonic procedure. After the coating process, LTO is covered by a homogeneous PEDOT:PSS layer, which effectively improves the electrical conductivity and processing capability of LTO to form a more homogeneous electrode sheet, and thus impart more favorable electrochemical kinetics as compared with the pristine LTO electrode. The LTO/PP electrode exhibits better reversible capacity and rate capability compared with the LTO electrode, delivering a reversible capacity of 177.2 mA h g⁻¹ at 0.1C and reaching a capacity of 169.1 mA h g⁻¹ with a capacity retention of 97.8% after 100 cycles at 0.5C. At the rate of 10C, the LTO/PP electrode delivers a capacity as high as 161.1 mA h g⁻¹ (91.0% of the value achieved at 0.1C), as compared to 144.5 mA h g⁻¹ for the pristine LTO electrode.