Graphene Aerogel-encapsulated Silicon Nanoparticles Mechanofused on Graphite without Prelithiation for Cylindrical Ni-rich NMC811 Li-ion Batteries

This is the authors' abstract. We don't add key points for this paper.

Silicon (Si), one of the promising anodes, provides a high theoretical specific capacity of ca. 3500 mAh g −1 at room temperature. It experiences many drastic issues, such as cost-effectiveness, large volume expansion, and unstable thick solid–electrolyte interfaces (SEI), leading to poor cycling stability. A small amount of Si has recently been added to graphite and used as the anode for commercial Li-ion batteries. Nevertheless, the intrinsic issues of Si still occur. Herein, we encapsulated Si nanoparticles with reduced graphene oxide (RGO) aerogel and graphite to obtain Si-RGO@Graphite using a dry surface coating technique so-called mechanofusion. This technique enhances the strong binding between these materials. We also demonstrated the practical use of the as-prepared Si-RGO@Graphite (9.9:0.1:90.0 wt% of Si:RGO:Graphite) anode coupling with Ni-rich NMC811 cathode at a 18650 cylindrical cell level. In this attempt, we avoid using an expensive vacuum-required prelithiation process, which currently inhibits the practical and commercial use of the Si-based anode. We believe this new composite material may be useful for high-energy LIBs in the future.