C–LiFePO4 composite was synthesized by mechanochemical 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°C and 60°C) and at C/20 rate between 2 and 4.5 V vs. Li + /Li were carried out with this C-LiFePO4 composite 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 ~ 80 % of the initial capacity maintained after 100 cycles. The electrodes recovered after long range cycling were characterized by X-ray diffraction; whatever the cycling temperature no significant structural changes (cell parameters, bond lengths, …) were shown to occur. Nevertheless, iron was found to be present at the negative electrode – as already observed by Amine and co-workers- 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
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