Effect of the synthesis conditions on the electrochemical properties of LiFePO4 obtained from NH4FePO4
| Autor: | Pier Paolo Prosini, Cinzia Cento, Maria Carewska, Paola Gislon, Amedeo Masci |
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| Přispěvatelé: | Masci, A., Carewska, M., Cento, C., Gislon, P., Prosini, P. P. |
| Rok vydání: | 2013 |
| Předmět: |
Materials science
Thermogravimetric analysis (TGA) Ammonium phosphate Precipitation (chemistry) Mechanical Engineering Lithium iron phosphate Sol-gel chemistry Inorganic chemistry Inorganic compounds Inorganic compound Condensed Matter Physics Phosphate Electrochemical measurement Lithium hydroxide Electrochemical measurements Electron microscopy chemistry.chemical_compound chemistry Mechanics of Materials Phase (matter) General Materials Science Crystallite Stoichiometry |
| Zdroj: | Materials Research Bulletin. 48:3438-3448 |
| ISSN: | 0025-5408 |
| DOI: | 10.1016/j.materresbull.2013.05.038 |
| Popis: | In this paper the morphological, structural and electrochemical properties of crystalline lithium iron phosphate (LiFePO4) obtained from ferrous ammonium phosphate (FAP) have been studied. The FAP was obtained following four different processes, namely: (1) homogeneous phase precipitation, (2) heterogeneous phase precipitation from stoichiometric sodium phosphate, (3) heterogeneous phase precipitation from stoichiometric ammonium phosphate, and (4) heterogeneous phase precipitation from over stoichiometric ammonium phosphate. Lithium iron phosphate was prepared by solid state reaction of FAP with lithium hydroxide. In order to evaluate the effect of reaction time and synthesis temperature the LiFePO4 was prepared varying the heating temperatures (550, 600 and 700 C) and the reaction times (1 or 2 h). The morphology of the materials was evaluated by scanning electron microscopy while the chemical composition was determined by electron energy loss spectroscopy. X-ray diffraction was used to evaluate phase composition, crystal structure and crystallite size. The so obtained LiFePO4's were fully electrochemical characterized and a correlation was found between the crystal size and the electrochemical performance. © 2013 Elsevier Ltd. All rights reserved. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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