Micro‐structured lepidocrocite‐type H <sub>1.07</sub> Ti <sub>1.73</sub> O <sub>4</sub> as anode for lithium‐ion batteries with an ultrahigh rate and long‐term cycling performance
Lijuan Hou, Rui-Chao Liu, Huiyu Yuan, Dezhi Kong, Weixia Shen, Jinhao Zang, Juan Guo, Shuge Dai, Minglang Wang, Tingting Xu, Xinjian Li, Ye Wang
Abstract
Abstract The lepidocrocite‐type H 1.07 Ti 1.73 O 4 microsized structures with a tap density of 0.88 g·cm −3 were prepared through the ion exchange method with K 0.8 Li 0.27 Ti 1.73 O 4 powder as the precursor, and they exhibited good rate performance and outstanding cycle stability as an anode material for lithium ion batteries (LIB). The ion exchange method provides favorable conditions for H 1.07 Ti 1.73 O 4 as an anode electrode material for LIBs. X‐ray photoelectron spectroscopy (XPS) result demonstrates the existence of defects in the nonstoichiometric H 1.07 Ti 1.73 O 4 , which have a beneficial effect on the LIB performance. The electrochemical performance test proves that the half‐cell with microsized H 1.07 Ti 1.73 O 4 as the anode electrode can maintain a specific capacity of 129.5 mAh·g −1 after 1100 cycles and 101 mAh·g −1 after 3000 long cycles at high current densities of 2.0 and 5.0 A·g −1 , respectively. In addition, the small volume change rate of 3.6% in H 1.07 Ti 1.73 O 4 during Li ion insertion was confirmed by real‐time in situ transmission electron microscopy (TEM). The LiFePO 4 ||H 1.07 Ti 1.73 O 4 full battery exhibits a long‐term cycling stability with a specific capacity of 73.8 mAh·g −1 at a current density of 500 mA·g −1 after 200 cycles.