Naoi, K., Kisu, K., Iwama, E., Nakashima, S., Sakai, Y., Orikasa, Y., Leone, P., Dupre, N., Brousse, T., Rozier, P., Naoi, W. & Simon, P. (2016) Ultrafast charge-discharge characteristics of a nanosized core-shell structured LiFePO4 material for hybrid supercapacitor applications. Energy Environ. Sci. 9 2143–2151.
Added by: Richard Baschera (2016-07-11 09:25:06) Last edited by: Richard Baschera (2016-07-11 09:26:57) |
Type de référence: Article DOI: 10.1039/c6ee00829a Numéro d'identification (ISBN etc.): 1754-5692 Clé BibTeX: Naoi2016 Voir tous les détails bibliographiques |
Catégories: INTERNATIONAL, ST2E Mots-clés: Carbon, Cathode material, Composites, devices, electrochemical energy-storage, Electrodes, graphene, intercalation, Lithium-ion batteries, nanoparticles Créateurs: Brousse, Dupre, Iwama, Kisu, Leone, Nakashima, Naoi, Naoi, Orikasa, Rozier, Sakai, Simon Collection: Energy Environ. Sci. |
Consultations : 1/694
Indice de consultation : 5% Indice de popularité : 1.25% |
Résumé |
Highly dispersed crystalline/amorphous LiFePO4 (LFP) nanoparticles encapsulated within hollow-structured graphitic carbon were synthesized using an in situ ultracentrifugation process. Ultracentrifugation triggered an in situ sol-gel reaction that led to the formation of core-shell LFP simultaneously hybridized with fractured graphitic carbon. The structure has double cores that contain a crystalline LFP (core 1) covered by an amorphous LFP containing Fe3+ defects (core 2), which are encapsulated by graphitic carbon (shell). These core-shell LFP nanocomposites show improved Li+ diffusivity thanks to the presence of an amorphous LFP phase. This material enables ultrafast discharge rates (60 mA h g(-1) at 100C and 36 mA h g(-1) at 300C) as well as ultrafast charge rates (60 mA h g(-1) at 100C and 36 mA h g(-1) at 300C). The synthesized core-shell nanocomposites overcome the inherent one-dimensional diffusion limitation in LFP and yet deliver/store high electrochemical capacity in both ways symmetrically up to 480C. Such a high rate symmetric capacity for both charge and discharge has never been reported so far for LFP cathode materials. This offers new opportunities for designing high-energy and high-power hybrid supercapacitors.
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