In Situ Synthesis of Multilayer Carbon Matrix Decorated with Copper Particles: Enhancing the Performance of Si as Anode for Li-Ion Batteries

Abstract

A 3D structured composite was designed to improve the conductivity and to ease the volume problems of Si anode during cycling for lithium-ions batteries. An in situ method via a controllable gelation process was explored to fabricate the 3D composite of a multilayer carbon matrix toughened by cross-linked carbon nanotubes (CNTs) and decorated with conductive Cu agents. Structurally, a bifunctional carbon shell was formed on the surface of Si to improve the conductivity but alleviate side reactions. Cu particles as conducting agents decorated in the carbon matrix are also used to further improve the conductivity. The volume issue of Si particles can be effectively released via toughening the carbon matrix through the multilayered structure and cross-linked CNTs. Moreover, the carbon matrix might prevent silicon particles from agglomeration. Consequently, the Si@C@Cu composite is expected to exhibit benign electrochemical performances with a commendable capacity of 1500 mAh g–1 (900 cycles, 1 A g–1) and a high rate performance (1035 mAh g–1, 4 A g–1). The DLi + ranging from 10–11 to 10–9 cm–2 s–1 of the Si@C@Cu anode is obtained via the GITT test, which is higher than most reported data.

Yolk‐Shell‐Structured Nanospheres with Goat Pupil‐Like S‐Doped SnSe Yolk and Hollow Carbon‐Shell Configuration as Anode Material for Sodium‐Ion Storage

“…Information on the parameter values is available in the literature. [ 48,49 ] In summary, SnSeS@C distinctly showed a higher average diffusion coefficient than SnSe‐C. This demonstrates the electrochemical performance of the heterostructured SnS/SnSe nanocomposite encapsulated by a sulfur‐doped carbon shell with high electrical conductivity.…”

Conversion Reaction Mechanism for Yolk‐Shell‐Structured Iron Telluride‐C Nanospheres and Exploration of Their Electrochemical Performance as an Anode Material for Potassium‐Ion Batteries

“…Information pertaining to the parameter values has been presented in previous papers. [42,43] The calculated results comparing FeTe 2 -C, bare FeTe 2 , FeTe@C electrodes are plotted according to various discharge/charge depths. FeTe 2 -C is clearly observed to have a higher average diffusion coefficient than bare FeTe 2 and FeTe@C, demonstrating the superiority of the uniformly distributed FeTe 2 nanocrystals embedded in carbon shell in terms of enhanced electrochemical performance.…”

Tubular Graphene Nano-Scroll Coated Silicon for High Rate Performance Lithium-Ion Battery

“…The Si@rGONSs-2 electrode shows a smaller R ct than commercial Si, which means a lower charge-transfer impedance (Fang et al, 2014). In the Nyquist plot, the first semicircle in the highfrequency region after cycling represents the ohmic resistance of the SEI layer, which could evaluate the stability of the SEI film (Zhang et al, 2019). As shown in Figure 4B, the R f value of commercial silicon is much higher than the Si@rGONSs-2 electrode, which means during cycling, the SEI film of the Si@rGONSs-2 is much stable compared to commercial Si.…”