Acta Phys. -Chim. Sin. ›› 2012, Vol. 28 ›› Issue (02): 349-354.doi: 10.3866/PKU.WHXB201112052

• ELECTROCHEMISTRY AND NEW ENERGY • Previous Articles     Next Articles

High Rate Capability and Cycling Stability of Li1.07Mn1.93O4 Nanoflakes Synthesized via Gel-Combustion Method

MAO Jing, DAI Ke-Hua, ZHAI Yu-Chun   

  1. School of Materials and Metallurgy, Northeastern University, Shenyang 110004, P. R. China
  • Received:2011-07-18 Revised:2011-11-24 Published:2012-01-11
  • Contact: DAI Ke-Hua, ZHAI Yu-Chun E-mail:daikh@smm.neu.edu.cn; zhaiyc@smm.neu.edu.cn

Abstract: Li1.07Mn1.93O4 nanoflakes were synthesized by a gel-combustion method using polyvinylpyrrolidone (PVP) as the polymer chelating agent and fuel. Thermogravimetric and differential thermal analyses (TG/DTA) were used to investigate the combustion process of the gel precursor. X-ray diffraction (XRD) analysis indicated that the as-prepared Li1.07Mn1.93O4 was a pure, highly crystalline phase. Scanning electron microscopy (SEM) results showed that most of the secondary particles were nanoflakes, about 100 nm in thickness, and the primary particle of the nanoflakes was about 100 nm in size. Charge and discharge tests suggested that the Li1.07Mn1.93O4 nanoflakes had excellent rate capability and good cycling stability. The initial discharge capacity was 115.4 mAh·g-1 at a rate of 0.5C (1C=120 mAh·g-1) and the capacity was maintained at 105.3 mAh·g-1 at the high discharge rate of 40C. When cycling at 10C, the material retained 81% of its initial capacity after 850 cycles. Electrochemical impedance spectroscopy (EIS) tests indicated that the charge-transfer resistance (Rct) of the Li1.07Mn1.93O4 nanoflakes was much less than that of commercial Li1.07Mn1.93O4.

Key words: Lithium ion battery, Lithium manganese oxide, Combustion synthesis, Rate capability, Cycling stability

MSC2000: 

  • O646