Development of advanced silicon anode material for Li-ion and K-ion batteries

Rechargeable Li-ion technology is considered as the battery of choice for electric vehicles and large-scale smart grids thanks to its unrivaled electrochemical properties (1). However, important amelioration in battery performance are still required, particularly in terms of energy density, power delivery capabilities and cycle life. The search for new highly efficient electrode materials for energy storage is an ongoing challenge for both basic and industrial applications (2-4). Silicon (Si) with high theoretical capacity of 4200 mAh.g-1 is one of the most promising LIB anodes and a potential candidate to replace commercial graphite for applications such as EVs. To ensure implementation of silicon in practical applications, the cyclic performance of Si needs crucial improvements. Indeed, silicon particles demonstrate large volume expansion in subsequent cycles that causes the capacity fading due to electrode pulverization (5). This drawback can be avoided through the formation of Silicon/carbon composites in which the size of the silicon particles and their dispersion is well controlled. In this work, the silicon-carbon composite particles in which silicon particles are intermixed with the conductive carbon network are prepared by spray drying as shaping method followed by a thermal treatment step under controller atmosphere (2, 6). The obtained composite demonstrates hollow spherical structure capable of withstanding and accommodate the expansion/shrinkage of Si upon lithiation/delithiation. The obtained Si/C anode material delivers a specific capacity of 1200 mAh.g-1, with capacity retention of 100% over long cycling performance of 1500 cycles which is more reliable as compared to other reported electrodes in the literature (6). We also show the primary results of the Si/C anode material for K-ion batteries (6). References 1. A. Mahmoud, I. Saadoune, P.-E. Lippens, M. Chamas, R. Hakkou, J.M. Amarilla, Solid State Ionics, 300 (2017), pp. 175-181. https://doi.org/10.1016/j.ssi.2016.12.012. 2. B. Vertruyen, N.Eshraghi, C. Piffet, J. Bodart, A. Mahmoud, F. Boschini. Materials 11 (2018) 1076. https://doi.org/10.3390/ma11071076. 3. C. Karegeya, A. Mahmoud, R. Cloots, B. Vertruyen, F. Boschini, Electrochimica Acta 250 (2017) 49–58. https://doi.org/10.1016/j.electacta.2017.08.006 4. C. Karegeya, A. Mahmoud, F. Hatert, B. Vertruyen, R. Cloots, P-E. Lippens, F. Boschini. J. Power Sources 388 (2018) 57-64. https://doi.org/10.1016/j.jpowsour.2018.03.069 5. N. Eshraghi, L. Berardo, A. Schrijnemakers, V. Delaval, M. Shaibani, M. Majumder, R. Cloots, B. Vertruyen, F. Boschini and A. Mahmoud, ACS Sustain. Chem. Eng., 8, 15 (2020) 5868–5879. https://doi.org/10.1021/acssuschemeng.9b07434 6. N. Eshraghi, A. Mahmoud, F. Boschini, R. Cloots, EP Patent EP3654413 (2020). ACKNOWLEDGMENTS The authors are grateful to the University of Liège and FRS-FNRS for the financial support. Part of this work was supported by the Walloon Region under the “PE PlanMarshall2. vert”program (BATWAL 1318146). A.M. is grateful to the Walloon region for a Beware Fellowship Academia 2015-1,RESIBAT no. 1510399 and University of Liége