Interfacial regulation constructing robust grape vine-like conductive network within silicon-based anode for high-performance lithium-ion batteries

Abstract

Silicon-based anodes hold significant promise for the development of next-generation lithium-ion batteries, attracting global attention due to their high theoretical capacity. However, silicon-based anodes undergo substantial volume expansion and high mechanical stress, which could disrupt conventional Super P (SP)-based conductive networks within the electrode, leading to capacity degradation. Furthermore, SP tends to agglomerate in aqueous solvents, which limits its conductive effectiveness. To address these challenges, we developed a composite material based on carbonized bacterial cellulose (CBC) and sodium carboxymethyl cellulose (CMC). This novel material enables uniform dispersion of SP, thereby constructing a robust grapevine-like structured conductive network. This network mimics the structure of a vine with grape clusters. The “grape clusters” consists of uniformly dispersed SP particles that serve as highly efficient conductive nodes. The “vine” structure, acting as a flexible and robust framework, enhances the mechanical properties of the electrode, thereby maintaining structural integrity of electrode during cycling. Consequently, the SiOx@CBC-CMC electrode exhibits impressive cycling and rate performances. Specifically, the electrode displays almost no capacity decay after 300 cycles at 0.5 C, and its average discharge specific capacity is as high as 535 mAh g-1 at 2 C. This work designed a novel conductive enhancement network, offering a promising pathway to overcome the conductive limitations within silicon-based anodes.