Electrochemical studies on electrospun Li(Li 1/3Ti 5/3)O 4 grains as an anode for Li-ion batteries

Abstract

Li(Li 1/3Ti 5/3)O 4 or (Li 4Ti 5O 12) (LTO) grains are prepared via electrospinning a solution containing lithium acetate, titanium tetra(IV)-isopropoxide, polyvinyl acetate and acetic acid in N,N-dimethyl-formamide, followed by a subsequent sintering process. The structures and morphology were characterized by X-ray diffraction, scanning and transmission microscopy. Coin-type cells were assembled to test the electrochemical performance was evaluated using galvanostatic cycling at room temperature, in the cycling range, 1.0-2.8 V. The Li-cycling results showed characteristic discharge-charge plateaus at 1.55 and 1.8 V vs. Li/Li +, respectively. Electrospun LTO showed a reversible capacity of 165(±3) mAh g -1 at the end of 10th cycle at a current rate of 0.2 C. The later studies on rate capacities and cycling performance of LTO grains demonstrate good rate performance and long term cycling stability. Galvanostatic Intermittent Titration Technique (GITT) and Electrochemical Impedance Spectroscopy (EIS) studied were carried out at end of 381st and 382nd cycle to understand the electrode kinetics. © 2012 Elsevier Ltd. All rights reserved.