Lithiation-delithiation kinetics of BaLi2Ti6O14 anode in high-performance secondary Li-ion batteries

In order to investigate the lithiation-delithiation kinetics in BaLi2Ti6O14 anode material, BaLi2Ti6O14 is achieved by a solid-state reaction process in this work. The as-prepared BaLi2Ti6O14 is high purity titanate and well crystallized with a particle size distribution in the range of 0.5-1.5 mu m. Electrochemical analysis shows that BaLi2Ti6O14 can deliver a reversible capacity of 126.1 mAh g(-1), at 5C, and the capacity retention is 74.1% after 1000 cycles. In addition, the electrochemical kinetics of BaLi2Ti6O14 is investigated by cyclic voltammetry (CV), in-situ electrochemical impedance spectroscopy (in-situ EIS) and galvanostatic intermittent titration (GITT) techniques. The DLi+ values calculated from CVs are located in the range of 10(-13)-10(-12) cm(2) s(-1). For comparison, the average Du values received from EIS and GITT methods are located in the range of 10(-14)-10(-72) cm(2) s(-1) and 10(-14)-10(-11) cm(2) s(-1), respectively. Although the DLi+ differs by several orders of magnittide from different measurement techniques, it still reveals higher value than that of Li4Ti5O12. Owing to the rapid diffusion kinetics of BaLi2Ti6O14, symmetrical structural evolutions can be observed via in-situ X-ray diffraction (XRD) study, which indicates that BaLi2Ti6O14 is a promising high-power anode candidate. (C) 2017 Elsevier B.V. All rights reserved.