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

• Published in: Ionics Vol. 15; no. 2; pp. 233 - 239
• Main Authors: Göktepe, H., Şahan, H., Patat, Ş., Ülgen, A.
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer-Verlag 01-04-2009
• Subjects: Chemistry; Chemistry and Materials Science; Condensed Matter Physics; Electrochemistry; Energy Storage; Optical and Electronic Materials; Original Paper; Renewable and Green Energy; Lithium-ion battery; Triple-metal doping; Oxide cathodes; Electrochemical properties; Substituted LiMn; O
• ISSN: 0947-7047; 1862-0760
• DOI: 10.1007/s11581-008-0265-5

To improve the cycle performance of spinel LiMn
2
O
4
as the cathode of 4-V-class lithium secondary batteries, spinel phases LiM
x
Mn
2 − 
x
O
4
(M=Li, Fe, Co;
x
 = 0, 0.05, 0.1, 0.15) and LiFe
0.05
M
y
Mn
1.95 − 
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
Mn
2 − 
x
O
4
(M=Li, Fe, Co;
x
 = 0, 0.05, 0.1, 0.15) and LiFe
0.05
M
y
Mn
1.95 − 
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 LiMn
2
O
4
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.