Vittorio Pellegrini: Graphene-based electrodes for high-power Li-ion batteries

Director IIT Graphene Labs, Istituto Italiano di Tecnologia, Genova (Italy), Co-founder of Bedimensional S.p.A In this talk I will first show that a novel laminated silicon-graphene heterostructure provides superior performance as anode nanomaterial in half and full Li-ion cells [1]. It is composed by dispersing carbon-coated polycrystalline silicon nanoparticles in between a few parallel oriented few-layers graphene flakes leading to high capacity values of around 1000 mAh/g at current values up to 3.5 A/g. On the cathode side, I will address a Lithium Iron Phosphate (LFP)-graphene nanohybrid obtained by a direct LFP crystal colloidal synthesis on few-layer graphene (FLG) flakes produced by LPE [2] offering a specific capacity exceeding 110 mAh/g at 20 C, with no electrode damaging. On Lithium Sulphur batteries, I will present a facile, non-aggressive and environmentally friendly strategy to perform a sulfur carbon composite material by simply dry a dispersion of elemental sulfur and graphene in ethanol solvent. The sample powder shows a suitable micrometric morphology exhibits a rate capability with a stable trend till current rate of 2C, a Coulombic efficiency approaching 100% for 300 cycles at the current rate of C/4 (420 mA g-1) and long cycle life up to 500 cycles delivering about 600 mAhg-1 at 2C (3350 mA g-1) [3]. [1] S. Palumbo, L. Silvestri, V. Pellegrini et al. ACS Appl. Energy Mater., 2 1793 (2019) [2] G. Longoni, et al., Nano Energy 51 656 (2018). [3] L. Carbone, V. Pellegrini et al. submitted. Vittorio Pellegrini holds a PhD degree in condensed matter physics and he is currently a research scientist at the Istituto Italiano di Tecnologia (IIT) in Genova and director of the IIT Graphene Labs. He is the head of division energy, composites and production of the European flagship project on graphene. He is also leader of the graphene flagship work-package energy storage. His current interests focus on the exploitation of twodimensional crystals for energy devices and for applications in composites. Vittorio Pellegrini has published more than 180 peer-reviewed papers and he is co-inventor of several patents. He gave more than 100 invited/keynote talks. He was Fellow of the Italian Academy at Columbia University (USA) in 2008, Winner of Campisano prize for condensed matter physics of the Italian National Research Council in 2008. He is cofunder of the start-up BeDimensional (www.bedimensional.it). He has published several articles for the general public in newspapers and scientific magazines and routinely gives talks at science festivals and at other public events.