Chemical Journal of Chinese Universities

• Article •    

Synthesis of Li2FeP2O7 Cathode Material at Different Temperatures and Its Electrochemical Performance for Lithium Ion Batteries

WANG Renheng1(), XIAO Zhe1, LI Yan1, SUN Yiling1, FANG Shuting1, ZHENG Junchao2, QIAN Zhengfang1(), HE Zhenjiang2()   

  1. 1.College of Physics and Optoelectronic Engineering,Shenzhen University,Shenzhen 518060,China
    2.School of Metallurgy and Environment,Central South University,Changsha 410083,China
  • Received:2020-08-31 Online:2021-01-05 Published:2021-01-05
  • Contact: WANG Renheng,QIAN Zhengfang,HE Zhenjiang E-mail:wangrh@szu.edu.cn;zq001@szu.edu.cn;hzjcsu@csu.edu.cn
  • Supported by:
    the Science and Technology Innovation Commission of Shenzhen City, China(20180123);the Guangdong Basic and Applied Basic Research Foundation of Guangdong Province, China(2019A1515012111);the National Natural Science Foundation of China(51804199);the Shenzhen Science and Technology Program, China(KQTD20180412181422399);the National Key R&D Program of China(2019YFB2204500)

Abstract:

The cathode material Li2FeP2O7 was synthesized via freeze-drying and followed by solid state sintering method. X-ray diffraction(XRD), scanning electron microscopy(SEM), transmission electron microscopy(TEM) and Fourier transform infrared spectroscopy(FTIR) were used to characterize the structure, composition and morphology of the material. In addition, the electrochemical performance of the Li2FeP2O7 material was investigated by cyclic voltammetry(CV) and electrochemical impedance spectroscopy(EIS). It was found that the greatest particle quality could be acquired when the synthesis temperature of Li2FeP2O7 was 590 ℃. The discharge specific capacity reached 55.0 mA·h·g?1 at 1.6C, which was much higher than that of the samples synthesized at other temperatures. The Li2FeP2O7 synthesized at 590 ℃ had a low impedance and a large exchange current density, which facilitated the diffusion of lithium ions and improved the electrochemical performance.

Key words: Lithium ion battery, Cathode, Li2FeP2O7, Solid state sintering method

CLC Number: