Enhanced cyclability of triple-metal-doped LiMn2O4 spinel as the cathode material for rechargeable lithium batteries


Goktepe H., Sahan H., PATAT Ş. , ÜLGEN A.

IONICS, cilt.15, ss.233-239, 2009 (SCI İndekslerine Giren Dergi) identifier identifier

  • Cilt numarası: 15 Konu: 2
  • Basım Tarihi: 2009
  • Doi Numarası: 10.1007/s11581-008-0265-5
  • Dergi Adı: IONICS
  • Sayfa Sayıları: ss.233-239

Özet

To improve the cycle performance of spinel LiMn2O4 as the cathode of 4-V-class lithium secondary batteries, spinel phases LiM (x) Mn2 -aEuro parts per thousand x O-4 (M=Li, Fe, Co; x = 0, 0.05, 0.1, 0.15) and LiFe0.05M (y) Mn1.95 -aEuro parts per thousand y O-4 (M=Li, Al, Ni, Co; y = 0.05, 0.1) were successfully prepared using the sol-gel method. The spinel materials were characterized by powder X-ray diffraction (XRD), elemental analysis, and scanning electron microscopy. All the samples exhibited a pure cubic spinel structure without any impurities in the XRD patterns. Electrochemical studies were carried out using the Li|LiM (x) Mn2 -aEuro parts per thousand x O-4 (M=Li, Fe, Co; x = 0, 0.05, 0.1, 0.15) and LiFe0.05M (y) Mn1.95 -aEuro parts per thousand y O-4 (M=Li, Al, Ni, Co; y = 0.05, 0.1) cells. These cathodes were more tolerant to repeated lithium extraction and insertion than a standard LiMn2O4 spinel electrode in spite of a small reduction in the initial capacity. The improvement in cycling performance is attributed to the stabilization in the spinel structure by the doped metal cations.