Chem. J. Chinese Universities

• Physical Chemistry • Previous Articles     Next Articles

Preparation and Electrochemical Performance of Na+-stabilized Layered LiNi0.6Co0.2Mn0.2O2 Cathode Material for Lithium-ion Batteries

ZHENG Zhuo1, WU Zhenguo2, XIANG Wei3, HUA Weibo2, GUO Xiaodong2,4   

  1. 1. Polymer Research Institute, Sichuan University, Chengdu 610065, China;
    2. School of Chemical Engineering, Sichuan University, Chengdu 610065, China;
    3. College of Materials and Chemistry & Chemical Engineering, Chengdu University of Technology, Chengdu 610059, China;
    4. Institute for Superconducting and Electronic Materials, University of Wollongong, Wollongong New South Wales(NSW)2522, Australia
  • Received:2016-11-09 Revised:2017-07-17 Online:2017-08-10 Published:2017-07-14
  • Supported by:

    Supported by the National Natural Science Foundation of China(No. 21506133).

Abstract:

Na-doped Li0.98Na0.02Ni0.6Co0.2Mn0.2O2 cathode material was synthesized through a simple oxalate co-precipitation. Powder X-ray diffraction(XRD), scanning electron microscopy(SEM), transmission electron microscopy(TEM), energy dispersive X-ray spectroscopy(EDS), inductively coupled plasma-atomic emission spectrometry(ICP-AES), electrochemical impedance spectroscopy(EIS) and galvanostatic charge-discharge tests were employed to analyze the particle morphology, crystal structure and electrochemical properties of the as-prepared materials. Results indicate that the Na-stabilized sample has a more ordered α-NaFeO2 structure(space group R3m), reduced Li+/Ni2+ cation mixing and enlarged Li layer spacing, which facilitates the fast insertion and extraction of Li+ ions in the bulk structure. Electrochemical results confirm that the Na-stabilized sample has excellent cycling stability and high rate performance. After 100 cycles at 1C between 2.7 V and 4.3 V, the cathode delivers a discharge capacity of 146 mA·h/g with capacity retention of 95.4%. At 0.1C, 0.2C, 0.5C, 1C, 3C, 5C, 10C and 20C, the specific capacities of the material are 181, 168, 162, 155, 143, 136, 126 and 113 mA·h/g, respectively. The Na-doping method is facile and feasible, which can provide some valuable reference for synthesizing other high rate and high capacity layered anode/cathode oxides.

Key words: Na-doped cathode material, Li+ diffusion path, Electrochemical performance, Lithium-ion battery

CLC Number: 

TrendMD: