LiV₃O₈/Polytriphenylamine Composites with Enhanced Electrochemical Performances as Cathode Materials for Rechargeable Lithium Batteries

Wenjuan Li; Limin Zhu; Ziheng Yu; Lingling Xie; Xiaoyu Cao

doi:10.3390/ma10040344

LiV₃O₈/Polytriphenylamine Composites with Enhanced Electrochemical Performances as Cathode Materials for Rechargeable Lithium Batteries

Materials (Basel). 2017 Mar 26;10(4):344. doi: 10.3390/ma10040344.

Authors

Wenjuan Li^{1

2}, Limin Zhu^{3

4}, Ziheng Yu⁵, Lingling Xie^{6

7}, Xiaoyu Cao^{8

9}

Affiliations

¹ School of Chemistry and Chemical Engineering, Henan University of Technology, Zhengzhou 450001, China. liwenjuan_1991@163.com.
² Key Laboratory of High Specific Energy Materials for Electrochemical Power Sources of Zhengzhou City, Henan University of Technology, Zhengzhou 450001, China. liwenjuan_1991@163.com.
³ School of Chemistry and Chemical Engineering, Henan University of Technology, Zhengzhou 450001, China. lmzhu@haut.edu.cn.
⁴ Key Laboratory of High Specific Energy Materials for Electrochemical Power Sources of Zhengzhou City, Henan University of Technology, Zhengzhou 450001, China. lmzhu@haut.edu.cn.
⁵ School of Pharmacy, China Pharmaceutical University, Nanjing 211196, China. zihengyu@126.com.
⁶ School of Chemistry and Chemical Engineering, Henan University of Technology, Zhengzhou 450001, China. linglingxie51@163.com.
⁷ Key Laboratory of High Specific Energy Materials for Electrochemical Power Sources of Zhengzhou City, Henan University of Technology, Zhengzhou 450001, China. linglingxie51@163.com.
⁸ School of Chemistry and Chemical Engineering, Henan University of Technology, Zhengzhou 450001, China. caoxy@haut.edu.cn.
⁹ Key Laboratory of High Specific Energy Materials for Electrochemical Power Sources of Zhengzhou City, Henan University of Technology, Zhengzhou 450001, China. caoxy@haut.edu.cn.

Abstract

LiV₃O₈/polytriphenylamine composites are synthesized by a chemical oxidative polymerization process and applied as cathode materials for rechargeable lithium batteries (RLB). The structure, morphology, and electrochemical performances of the composites are characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, galvanostatic discharge/charge tests, and electrochemical impedance spectroscopy. It was found that the polytriphenylamine particles were composited with LiV₃O₈ nanorods which acted as a protective barrier against the side reaction of LiV₃O₈, as well as a conductive network to reduce the reaction resistance among the LiV₃O₈ particles. Among the LiV₃O₈/polytriphenylamine composites, the 17 wt % LVO/PTPAn composite showed the largest d₁₀₀ spacing. The electrochemical results showed that the 17 wt % LVO/PTPAn composite maintained a discharge capacity of 271 mAh·g^-1 at a current density of 60 mA·g^-1, as well as maintaining 236 mAh·g^-1 at 240 mA·g^-1 after 50 cycles, while the bare LiV₃O₈ sample retained only 169 and 148 mAh·g^-1, respectively. Electrochemical impedance spectra (EIS) results implied that the 17 wt % LVO/PTPAn composite demonstrated a decreased charge transfer resistance and increased Li⁺ ion diffusion ability, therefore manifesting better rate capability and cycling performance compared to the bare LiV₃O₈ sample.

Keywords: LiV3O8/polytriphenylamine composites; cathode materials; electrochemical performances; in situ chemical polymerization method; rechargeable lithium batteries.