Vertical Graphene Nanosheets on Porous Microsilicon Particles for Anodes of Lithium-Ion Batteries

Abstract

Silicon is receiving significant attention among different anode materials for Li-ion batteries due to its superhigh theoretical energy density. However, the commercial application of Si anode is facing huge obstacles because of the inferior electrical conductivity, the pulverization arising from the volume change, and the high cost of nanosilicon. Herein, we demonstrate a facile method to achieve excellent performance by in situ growing vertical graphene shell on microsilicon. The vertical graphene nanosheets can be conformally grown on porous microsilicon particles embedded with nanosilver particles to form the graphene-encapsulated porous Si@Ag particles (VG-PMSi@Ag). The unique structure integrates high conductivity and flexibility, which accelerate the charge transport and accommodate the volume change of silicon during the cycling process. As a result, the batteries exhibit a high initial discharge capacity of 3121.6 mAh·g–1 at 0.1 A·g–1 and a high rate capability of 943.8 mAh·g–1 at 6 A·g–1. A high reversible capacity of 1403.9 mAh·g–1 at 2.0 A·g–1 after 100 cycles is achieved. This approach offers insights into the fabrication of silicon anodes for high-performance lithium-ion batteries.

Recent advancements in 3D porous graphene-based electrode materials for electrochemical energy storage applications

“…The influence of graphene on enhancing the electrochemical performance of silicon materials for LIBs was studied in this work. 42 Silicon is already a growing field in LIBs due to its high theoretical capacitance (4200 mA h g −1 ), 43 but in practice, it has many drawbacks due to its low electrical and cycling performances. In this work, 42 an attempt was made to overcome the above-mentioned drawback by designing this silicon-based electrode in such a way that it enhances the conductivity and cycling stability.…”

“…42 Silicon is already a growing field in LIBs due to its high theoretical capacitance (4200 mA h g −1 ), 43 but in practice, it has many drawbacks due to its low electrical and cycling performances. In this work, 42 an attempt was made to overcome the above-mentioned drawback by designing this silicon-based electrode in such a way that it enhances the conductivity and cycling stability. The nanosilver encapsulated on the surface of porous micro-silicon (as in Fig.…”

“…(C) Long-term cycling activity of the VG-PMS@Ag electrode at different applied current densities. Reprinted with permission, 42 Copyright [2022] American Chemical Society.…”

“…5A). The influence of graphene on enhancing the electrochemical performance of silicon material for LIB was studied in this work [42]. Silicon is already a growing field in LIB due to its high theoretical capacitance (4200 mA h/g -1 ) [43], but in practice, it has many drawbacks due to its low electrical and cycling performances.…”

Wrapping silicon microparticles by using well-dispersed single-walled carbon nanotubes for the preparation of high-performance lithium-ion battery anode

“…The large surface area of the composite could result in increased electrolyte consumption and more SEI layer formation, resulting in low initial coulombic efficiency. 44–46 The result implies the superior electrochemical performance of the SiMP/CNT wrapping 9 : 1, even with a smaller amount of SWCNTs. The better electrochemical performance of the SiMP/CNT wrapping 9 : 1 electrode is attributed to the optimal structural properties of thin 2D SWCNT wrapping on the SiMPs.…”