In situ LiFePO4 nano-particles grown on few-layer graphene flakes as high-power cathode nanohybrids for lithium-ion batteries. (September 2018)

• Record Type: Journal Article
• Authors: Longoni, Gianluca; Panda, Jaya Kumar; Gagliani, Luca; Brescia, Rosaria; Manna, Liberato; Bonaccorso, Francesco; Pellegrini, Vittorio
• Is Part Of: Nano energy. Volume 51(2018)
• Page Start: 656
• Page End: 667
• Publication Date: 2018-09
• Subjects: Lithium-ion batteries -- Graphene flakes -- Liquid-phase exfoliation -- Iron Phosphate -- High-rate; Nanoscience -- Periodicals; Nanotechnology -- Periodicals; Nanostructured materials -- Periodicals; Power resources -- Technological innovations -- Periodicals; Nanoscience; Nanostructured materials; Nanotechnology; Power resources -- Technological innovations; Periodicals; 621.042
• DOI: 10.1016/j.nanoen.2018.07.013
• Languages: English
• ISSNs: 2211-2855

Abstract

Abstract: We have realized a Lithium Iron Phosphate (LFP)-graphene nanohybrid obtained by a direct LFP crystal colloidal synthesis on few-layer graphene (FLG) flakes produced by the liquid phase exfoliation (LPE) of pristine graphite. This hybrid material has been tested as a cathode in Li-ion batteries, achieving fast charge/discharge responses to high specific currents. We demonstrate a specific capacity exceeding 110 mAh g −1 at 20 C, with no electrode damaging. Our LFP-FLG electrodes display a low charge transfer resistance, chemical stability and steady electrochemical behavior even under stressful conditions, such as impulsive charges at a high-rate (5 C) and long cycles at 1 C (> 700 cycles). The LFP colloidal synthesis combined with the FLG production by LPE allows for tuning both the LFP-platelets like and FLG flake morphologies in order to promote an optimal connection between the LFP and FLG flakes, ensuring fast charge transfers and consequently high-rate electrochemical performances. The method here proposed yields a scalable production path, which can be easily extended to silicate-, phosphate- and fluorophosphates-based cathode materials for the next generation of high-power lithium batteries. Graphical abstract: fx1 Highlights: Unravelling the role of graphene nanoflakes as a new templating material for the preparation of LiFePO4 -graphene hybrid, exploited as cathode in a lithium ion battery. Solution processing. Hybrid electrodes. 2D nanomaterials. Environmentally-friendly.