Abstract :
[en] Lithium-ion batteries have been widely applied as a power source for portable and stationary energy storage systems. Na-ion batteries are considered to be an alternative to Li-ion batteries owing to the natural abundance of sodium. New electrode materials are required to increase the energy density of Li/Na-ion batteries. In this study, we show that the addition of the carbon sources during the synthesis leads to control the particles size and morphology and improve their conductivity properties that enhance the electrochemical performance [1-5].
In order to study the effect of the carbon on the structural, morphological and electrochemical properties of the prepared materials by a spray-drying [1-3] or hydrothermal methods [4, 5]. The crystal and local structure were analyzed by XRD and Mössbauer spectroscopy. The morphological properties were characterized by SEM and TEM. The carbon content was determined by TG/TDA and carbon analyzer. The electrochemical properties were studied by impedance spectroscopy and galvanostatic cycling in lithium cells. Finally, the reaction mechanism during cycling was investigated using operando XRD technique.
1- A. Mahmoud, S. Caes, M. Brisbois, R.P. Hermann, L. Berardo, A. Schrijnemakers, C. Malherbe, G. Eppe, R. Cloots, B. Vertruyen, F. Boschini, Spray-drying as a tool to disperse conductive carbon inside Na2FePO4F particles by addition of carbon black or carbon nanotubes to the precursor solution, J. Solid State Electrochem. (2017) 1–10.
2- N. Eshraghi, S. Caes, A. Mahmoud, R. Cloots, B. Vertruyen, F. Boschini, Sodium vanadium (III) fluorophosphate/carbon nanotubes composite (NVPF/CNT) prepared by spray-drying: good electrochemical performance thanks to well-dispersed CNT network within NVPF particles, Electrochim. Acta, 228 (2017) 319–324.
3- M. Brisbois, S. Caes, M-T. Sougrati, B. Vertruyen, A. Schrijnemakers, R. Cloots, N. Eshraghi, R-P. Hermann, A. Mahmoud, F. Boschini, Na2FePO4 F/multi-walled carbon nanotubes for lithium-ion batteries: Operando Mössbauer study of spray-dried composites, Solar Energy Materials & Solar Cells 148 (2016) 67-72.
4- C. Karegeya, A. Mahmoud, B. Vertruyen, F. Hatert, R.P. Hermann, R. Cloots, F. Boschini, One-step hydrothermal synthesis and electrochemical performance of sodium-manganese-iron phosphate as cathode material for Li-ion batteries, J. Solid State Chem.253 (2017) 389–397.
5- C. Karegeya, A. Mahmoud, R. Cloots, B. Vertruyen, F. Boschini, Hydrothermal synthesis in presence of carbon black: Particle-size reduction of iron hydroxyl phosphate hydrate for Li-ion battery, Electrochimica Acta. Electrochim. Acta 250 (2017) 49–58.
