The future of energy sustainability is linked to the development of efficient energy storage facilities [1]. For an increasingly diverse range of application, spanning from automotive to portable high-end electronics, lithium-ion battery technology plays a pivotal role today, and will continue to do so over the next few years[2,3]. However, to extend their use, these systems require further improvements either in terms of energy density and cycle life performance [4]. In this context, the choice of proper anode and cathode materials plays a pivotal role [5].

In this talk I will show that a novel laminated silicon-graphene heterostructure provides superior performance as anode nanomaterial in half and full Li-ion cells [6,7]. It is composed by dispersing carbon-coated polycrystalline silicon nanoparticles in between a few parallel oriented few-layers graphene flakes produced by liquid phase exfoliation (LPE) 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 [8]. In Li-ion batteries, we achieve 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. 

The method here proposed yields a scalable production path of novel graphene-based materials for the next generation of high-power lithium batteries.

Acknowledgements 

*work done in collaboration with Laura Silvestri, Stefano Palumbo, Francesco Bonaccorso, Gianluca Longoni, Liberato Manna

References 

[1] M. Armand, J.-M. Tarascon, Building better batteries., Nature. 451 (2008) 652. 

[2] K. Mizushima, P.C. Jones, P.J. Wiseman, J.B. Goodenough, LixCoO2 (0<x<1): A new cathode material for batteries of high energy density, Solid State Ionics. 4 (1981) 171.

[3] B. Nykvist, M. Nilsson, Rapidly falling costs of battery packs for electric vehicles, Nat. Clim. Chang. 5 (2015) 329.

[4] C.P. Grey, J.M. Tarascon, Sustainability and in situ monitoring in battery development, Nat. Publ. Gr. 16 (2017). 

[5] F. Bonaccorso, et al., Graphene, 2d crystal and hybrid structures for energy conversion and storage. Science 347 (2015), 1246501.

[6] E. Greco, G. Nava, R. Fathi, F. Fumagalli, A.E. Del Rio-Castillo, A. Ansaldo, S. Monaco, F. Bonaccorso, V. Pellegrini, F. Di Fonzo. Few-layer graphene improves silicon performance in Li-ion battery anodes, J. Material Chemistry A 5 (2017) 19306.

[7] S. Palumbo, L. Silvestri, V. Pellegrini et al. In preparation. 

[8] G. Longoni, J.K. Panda, L. Gagliani, R. Brescia, L. Manna, F. Bonaccorso, V.  Pellegrini, in situ LiFePO4 nano-particles grown on few-layer graphene flakes as high-power cathode nanohybrids for lithium-ion batteries, Nano Energy 51 (2018) 656.

The future of energy sustainability is linked to the development of efficient energy storage facilities [1]. For an increasingly diverse range of application, spanning from automotive to portable high-end electronics, lithium-ion battery technology plays a pivotal role today, and will continue to do so over the next few years[2,3]. However, to extend their use, these systems require further improvements either in terms of energy density and cycle life performance [4]. In this context, the choice of proper anode and cathode materials plays a pivotal role [5].

In this talk I will show that a novel laminated silicon-graphene heterostructure provides superior performance as anode nanomaterial in half and full Li-ion cells [6,7]. It is composed by dispersing carbon-coated polycrystalline silicon nanoparticles in between a few parallel oriented few-layers graphene flakes produced by liquid phase exfoliation (LPE) 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 [8]. In Li-ion batteries, we achieve 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. 

The method here proposed yields a scalable production path of novel graphene-based materials for the next generation of high-power lithium batteries.

Acknowledgements 

*work done in collaboration with Laura Silvestri, Stefano Palumbo, Francesco Bonaccorso, Gianluca Longoni, Liberato Manna

References 

[1] M. Armand, J.-M. Tarascon, Building better batteries., Nature. 451 (2008) 652. 

[2] K. Mizushima, P.C. Jones, P.J. Wiseman, J.B. Goodenough, LixCoO2 (0<x<1): A new cathode material for batteries of high energy density, Solid State Ionics. 4 (1981) 171.

[3] B. Nykvist, M. Nilsson, Rapidly falling costs of battery packs for electric vehicles, Nat. Clim. Chang. 5 (2015) 329.

[4] C.P. Grey, J.M. Tarascon, Sustainability and in situ monitoring in battery development, Nat. Publ. Gr. 16 (2017). 

[5] F. Bonaccorso, et al., Graphene, 2d crystal and hybrid structures for energy conversion and storage. Science 347 (2015), 1246501.

[6] E. Greco, G. Nava, R. Fathi, F. Fumagalli, A.E. Del Rio-Castillo, A. Ansaldo, S. Monaco, F. Bonaccorso, V. Pellegrini, F. Di Fonzo. Few-layer graphene improves silicon performance in Li-ion battery anodes, J. Material Chemistry A 5 (2017) 19306.

[7] S. Palumbo, L. Silvestri, V. Pellegrini et al. In preparation. 

[8] G. Longoni, J.K. Panda, L. Gagliani, R. Brescia, L. Manna, F. Bonaccorso, V.  Pellegrini, in situ LiFePO4 nano-particles grown on few-layer graphene flakes as high-power cathode nanohybrids for lithium-ion batteries, Nano Energy 51 (2018) 656.