Sathiya, M and Hemalatha, K and Ramesha, K and Shukla, AK and Prakash, AS (2011) Nitrates-melt synthesized LiNi0.8Co0.2O2 and its performance as cathode in Li-ion cells. In: BULLETIN OF MATERIALS SCIENCE, 34 (7). pp. 1693-1698.
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Abstract
Layered LiNi0.8Co0.2O2 crystallizing in R (3) over barm space group is synthesized by decomposing the constituent metal-nitrate precursors. Oxidizing nature of metal nitrates stabilizes nickel in +3 oxidation state, enabling a high degree of cation ordering in the layered LiNi0.8Co0.2O2. The powder sample characterized by XRD Rietveld refinement reveals <2% Li-Ni site exchange in the layers. Scanning electron microscopic studies on the as-synthesized LiNi0.8Co0.2O2 sample reflect well defined particles of cubic morphology with particle size ranging between 200 and 250 nm. Cyclic voltammograms suggest that LiNi0.8Co0.2O2 undergoes phase transformation on first charge with resultant phase being completely reversible in subsequent cycles. The first-charge-cycle phase transition is further supported by impedance spectroscopy that shows substantial reduction in resistance during initial de-intercalation. Galvanostatic charge-discharge cycles reflect a first-discharge capacity of 184 mAh g(-1) which is stabilized at 170 mAh g(-1) over 50 cycles.
Item Type: | Journal Article |
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Publication: | BULLETIN OF MATERIALS SCIENCE |
Publisher: | INDIAN ACAD SCIENCES |
Additional Information: | Copyright for this article belongs to the Indian Academy of Sciences |
Keywords: | Lithium batteries;intercalation compounds;electrochemical characterization;diffusion |
Department/Centre: | Division of Chemical Sciences > Solid State & Structural Chemistry Unit |
Date Deposited: | 22 Jun 2012 10:53 |
Last Modified: | 22 Jun 2012 10:53 |
URI: | http://eprints.iisc.ac.in/id/eprint/44725 |
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