Dispersant‐Free Colloidal and Interfacial Engineering of Si‐Nanocarbon Hybrid Anode Materials for High‐Performance Li‐Ion Batteries

Abstract

Highly conducting nanomaterials have garnered significant attention owing to their potential application in Li‐ion batteries for stable electrodes. However, concerns persist regarding their dispersion and effective hybridization with active materials. This study reports a novel approach to enhance Si‐based anode materials using less defective graphene oxide (C‐GO) and highly oxidized single‐walled carbon nanotubes (C‐SWCNTs) fabricated using chlorate‐based oxidation. The method involves encapsulating Si alloy (SiA) particles with C‐GO and C‐SWCNTs, eliminating the need for additional additives. Composite structures with lithiophilic N‐doped SWCNTs and highly crystalline reduced C‐GO coatings on SiA surfaces are created through spray drying and subsequent chemical reduction. This unique combination yields high capacities, stable retention behaviors, and remarkable initial capacities (1224 mAh g−1) with excellent retention rates (82.3% at 100 cycles, 0.1 C). A LIB full‐cell with a SiA/nanocarbon anode exhibited a high energy density of 350 Wh kg−1, while maintaining 65% capacity retention after 200 cycles. The findings demonstrate the potential of this hybrid approach, which eliminates the need for other conducting additives while maintaining a minimal binder content (5 wt.%). This study presents a promising approach for enhancing Si‐based anode materials in lithium‐ion batteries, addressing the dispersion and hybridization challenges in nanomaterial‐enabled electrode design.

What Is the Real Origin of Single-Walled Carbon Nanotubes for the Performance Enhancement of Si-Based Anodes?

“…Thus, the full cell is potential to deliver a high energy density of 493 Wh kg (anode + cathode) –1 at 0.83C with high reversibility, outperforming the overall performance of most Si-based full cells reported previously (Figure S27b and Table S2). − Most importantly, this superior performance can be achieved only with the addition of 1 wt % SWNTs in the composite anodes. The electrochemical performance of the SiO x -1 wt % SWNT anode was further checked in a full-cell configuration with a counter electrode of NCM811 (Figure S28), which displayed comparable capacities as those in half-cells (Figure S14).…”

Hierarchical Nanoporous N-Doped Carbon for Enhanced Rate Performance of Lithium-Ion Battery Anodes

“…Carbon-based anode materials possessing identical dimensions and geometries as the constituent particles can show diverse interlayer spacing, distinct polarization characteristics, varied metal ion-plating, stress management, and capacity fade . In this regard, several carbonaceous materials with different characteristics, such as carbon nanotubes (CNTs), expanded carbon, pyrolytic carbons, carbon nanodots, graphitic carbon (GC), functionalized carbon, and so on, have been incorporated as anode materials. Among these, GC has gained significant attention due to randomly oriented graphitic domains along with amorphous structures .…”