Electrochemical performances in temperature for a C-containing LiFePO4 composite synthesized at high temperatureReportar como inadecuado




Electrochemical performances in temperature for a C-containing LiFePO4 composite synthesized at high temperature - Descarga este documento en PDF. Documentación en PDF para descargar gratis. Disponible también para leer online.

1 ICMCB - Institut de Chimie de la Matière Condensée de Bordeaux 2 Laboratoire Composants pour l?Energie

Abstract : C-LiFePO4 composite was synthesized by mechano-chemical activation using iron and lithium phosphates and also cellulose as carbon precursor; this mixture was heated at 800 °C under argon during a short time. Long-range cyclings at different temperatures RT, 40 and 60 °C and at C-20 rate between 2 and 4.5 V vs. Li+-Li were carried out with this C-LiFePO4 material as positive electrode material in lithium cells. Whatever the cycling conditions used, rather good electrochemical performances were obtained, with a capacity close to the theoretical one and a good cycle life, especially at RT – up to 100 cycles – and at 40 °C with not, vert, similar80% of the initial capacity maintained after 100 cycles. The electrodes recovered after long-range cyclings were characterized by X-ray diffraction; whatever the cycling temperature no significant structural changes cell parameters, bond lengths, etc. were shown to occur. Nevertheless, iron was found to be present at the negative electrode – as already observed by Amine et al. – after long-range cycling at 60 °C: other analyses have to be done to identify the origin of this iron from an impurity or from LiFePO4 itself and to quantify this amount vs. that of active C-LiFePO4 material using larger cells.

Keywords : Lithium-ion batteries LiFePO4 Electrochemical properties Cycling in temperature Structural stability X-ray diffraction





Autor: Magalie Maccario - Laurence Croguennec - F. Le Cras - Claude Delmas -

Fuente: https://hal.archives-ouvertes.fr/



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