Quantitative structural analysis of the transition from LT-Li xCoO2 to HT-LixCoO2 using the rietveld method: Correlation between structure and electrochemical performance

Nenhuma Miniatura disponível

Data

2004-01-02

Autores

Santiago, Elisabete I.
Bueno, Paulo R.
Andrade, André Vitor C.
Paiva-Santos, Carlos O. [UNESP]
Bulhões, Luis Otavio S.

Título da Revista

ISSN da Revista

Título de Volume

Editor

Resumo

A quantitative phase analysis was made of LixCoO2 powders obtained by two distinct chemical methodologies at different temperatures (from 400 to 700°C). A phase analysis was made using Rietveld refinements based on X-ray diffraction data, considering the Li xCoO2 powders as a multiphase system that simultaneously contained two main phases with distinct, layered and spinel-type structures. The results showed the coexistence of both structures in LixCoO 2 obtained at low temperature (400 and 500°C), although only the layered structure was detected at higher temperatures (600 and 700°C), regardless of the chemical powder process employed. The electrochemical performance, evaluated mainly by the cycling reversibility of Li xCoO2 in the form of cathode insertion electrodes, revealed that there is a close correlation between structural features and the electrochemical response, with one of the redox processes (3.3 v/3.9 v) associated only with the presence of the spinel-type structure. © 2003 Elsevier B.V. All rights reserved.

Descrição

Palavras-chave

Insertion electrodes, LixCoO2, Lithium battery, Rietveld method, X-ray structural refinement, Electrochemistry, High temperature effects, Lithium batteries, Low temperature effects, Neutron diffraction, Oxidation, Phase transitions, Redox reactions, Structure (composition), X ray diffraction analysis, Rietveld refinements (RR), Structural stability, Lithium compounds

Como citar

Journal of Power Sources, v. 125, n. 1, p. 103-113, 2004.