Structural, electrical and electrochemical behaviours of LiNi0·4M0·1Mn1·5O4 (M = Al, Bi) as cathode material for Li-ion batteries

• Published in: Bulletin of materials science Vol. 37; no. 3; pp. 705 - 711
• Main Authors: Nayaka, G P, Manjanna, J, Anjaneya, K C, Manikandan, P, Periasamy, P, Tripathi, V S
• Format: Journal Article
• Language: English
• Published: India Springer India 01-05-2014; Springer Nature B.V
• Subjects: Cathodes; Chemistry and Materials Science; Differential thermal analysis; Electrode materials; Engineering; Ion migration; Lithium manganese oxides; Lithium-ion batteries; Materials Science; Nyquist plots; Rechargeable batteries; Sol-gel processes; Solid solutions; Structural analysis; Surface layers; Lithium ion batteries; Mn; cyclic voltammetry; Al, Bi; (; a.c.-impedance; LiNi; O; charge/discharge
• ISSN: 0250-4707; 0973-7669
• DOI: 10.1007/s12034-014-0710-1

In order to improve the cycling performance of LiMn
2
O
4
based cathode materials, we have synthesized a new composition, LiNi
0·4
M
0·1
Mn
1·5
O
4
(
M
= Al, Bi), by the sol–gel method. The formation of solid solutions is confirmed by structural characterization using TG/DTA, XRD, FT–IR, EPR, SEM and EPR. A.c.-impedance (Nyquist plot) showed a high frequency semicircle and a sloping line in the low-frequency region. The semicircle is ascribed to the Li-ion migration through the interface from the surface layer of the particles to the electrolyte. Cyclic voltammogram (between 3·5 and 4·9 V) for these materials using CR2032 coin-type cell shows two pairs of redox peaks corresponding to two-step reversible intercalation process, wherein Li-ions occupy two different tetragonal 8a sites in spinel Li
x
Mn
2
O
4
(
x
< 1) lattice. The galvanostatic charge/discharge curves for
M
= Al (77 mAh g
–1
) showed reasonably good capacity retention than that of
M
= Bi (11 mAh g
–1
) at the end of 17th cycle.