Surficial amide-enabled integrated organic anode–binder electrode for electrochemical reversibility and fast redox kinetics in lithium–ion batteries

Abstract

Binders have been focused on the improvement of electrode stability. However, they have great potential to enhance the electrochemical properties by introducing additional interaction with functional groups of organic electrodes. In this study, we propose an integrated organic anode–binder system from small molecule to polymer. It comprises a redox-active benzene group for highly stable and fast lithium-ion batteries via chemical cross-linking of the aromatic redox-active molecule with the poly(acrylic acid) binder. The surficial amide linkage not only suppresses electrolyte dissolution but also increases the lithium-ion reaction kinetics of the benzene ring with high reversible capacity. The lowered lowest unoccupied molecular orbital level and lithium-ion induction effect reduce the charge transfer and interface resistance, significantly outperforming the traditional electrode system with a poly(vinylidene fluoride) binder. This strategy is successfully expanded to polymeric system of polyimide microparticles possessing additional redox-active imide moiety along with benzene rings in their backbone. This work suggests a new strategy of providing additional capacity through reaction kinetics enhancement for multiscale redox-active organic materials.