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

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.