Sea Urchin-like Si@MnO2@rGO as Anodes for High-Performance Lithium-Ion Batteries

Abstract

Si is a promising material for applications as a high-capacity anode material of lithium-ion batteries. However, volume expansion, poor electrical conductivity, and a short cycle life during the charging/discharging process limit the commercial use. In this paper, new ternary composites of sea urchin-like Si@MnO2@reduced graphene oxide (rGO) prepared by a simple, low-cost chemical method are presented. These can effectively reduce the volume change of Si, extend the cycle life, and increase the lithium-ion battery capacity due to the dual protection of MnO2 and rGO. The sea urchin-like Si@MnO2@rGO anode shows a discharge specific capacity of 1282.72 mAh g−1 under a test current of 1 A g−1 after 1000 cycles and excellent chemical performance at different current densities. Moreover, the volume expansion of sea urchin-like Si@MnO2@rGO anode material is ~50% after 150 cycles, which is much less than the volume expansion of Si (300%). This anode material is economical and environmentally friendly and this work made efforts to develop efficient methods to store clean energy and achieve carbon neutrality.

Engineering electrode microstructures for advanced lithium-ion batteries

“…Reproduced with the permission of Ref. [62] Copyright 2021, Springer Nature. (D) Concise preparation schematics of the Si@MnO 2 @reduced graphene oxide (rGO) composites and long-term cycling performance of the Si@MnO 2 @rGO-50 °C at 1 A g -1 .…”

“…This core may function as an electrolyte reservoir, and the nanorods facilitate rapid diffusion of the electrolyte and effectively accommodate the strain generated during cycling [61] . Zhang et al manufactured urchin-like MnO/C microspheres by a hydrothermal technique and thermal degradation of polyvinyl alcohol (PVA) on the MnO surface [Figure 2C] [62] . The electrochemical performance for lithium storage is enhanced in u-MnO/C due to its distinctive hierarchical nanostructures and carbon coatings.…”

Strategies for Controlling or Releasing the Influence Due to the Volume Expansion of Silicon inside Si−C Composite Anode for High-Performance Lithium-Ion Batteries

“…Su et al prepared multi-layer carbon-coated silicon Si@C@RGO [98]. Liu et al successfully prepared an Si@MnO 2 @rGO anode using a hydrothermal method [99]. As shown in Figure 4b, after 150 cycles, the volume expansion of the Si@MnO 2 @rGO electrode was only 59%, while the bare silicon electrode was as high as 198%.…”

“…Copyright 2018, Carbon. (b) Cross-sectional SEM images of Si and Si@MnO 2 @rGO, before and after 150 cycles[99]. Reprinted with permission from Ref [99]…”

A Review of MnO2 Composites Incorporated with Conductive Materials for Energy Storage

“…Deng et al [161] synthesized MnO 2 @PANI@GO composites based on graphite paper using in-situ electrochemical oxidation and applied them for the first time to the cathode of Mg//seawater batteries, and the assembled Mg//seawater batteries had a higher operating voltage (1.46 V) and higher energy density (544 mWh • g À 1 ) than the traditional cell. In addition, there are many studies on ternary composites in batteries, such as MnO 2 @graphene@CF, [162] MnO 2 @conducting polymer@vertical graphene (VG), [163] MnO 2 @CNT@Co, [164] and MnO 2 @Si@rGO, [165] all of which further expand and improve this part and pave the way for future studies.…”