Parthenocissus-inspired self-healing and strongly adhesive binder for high-performance Si anodes in lithium-ion batteries

초록

Polyacrylic acid (PAA) based-binders equipped with various functions are paramount importance in suppressing the expansion of silicon (Si)-based anodes. However, PAA molecules tend to slip from the surface of active materials during the expansion of Si-based anode due to their 1D linear structure. In this study, inspired by the strong adhesion mechanism of multiple antennae of Parthenocissus, a new polymer binder based on boronic acid (BA) and dopamine-modified PAA with fast self-healing, strong adhesion and stable mechanical performances is synthesized. Due to the abundant dynamic hydrogen bonds, the binder exhibit fast self-healing function at room temperature, thus guaranteeing the superior cycle stability of the electrode. These dynamic hydrogen bond sites not only endow the binder with strong adhesion but also contribute to an average peeling force of 1.50 N for Si@PDB, significantly higher than that of Si@PAA (0.79 N) and Si@PAB (1.29 N). Consequently, the Si anodes utilizing the rationally designed binder demonstrate excellent cycling stabilities (2538 mAh g -1 after 200 cycles) and rate performances (1973 mAh g -1 at 8.0 A g-1 ). These results suggest that the biomimetic binder can serve as a promising and effective candidate for Si-based anodes towards high-performance lithium-ion batteries.

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