Bollard‐Anchored Binder System for High‐Loading Cathodes Fabricated via Dry Electrode Process for Li‐Ion Batteries

Abstract

Abstract The dry battery electrode (DBE) process offers significant advantages over conventional wet‐coating methods for electrode fabrication. Unlike traditional processes that rely on toxic solvents such as N‐methyl‐2‐pyrrolidone (NMP), the DBE technique uses solvent‐free methods, reducing environmental impact and production costs while enhancing compatibility and performance. However, polytetrafluoroethylene (PTFE), the only binder currently used for large‐scale DBE fabrication (binder fibrillation), faces potential regulatory restrictions under Polyfluoroalkyl Substances (PFAS) guidelines and limits Li‐ion conductivity, elastomeric properties, and particle adhesion. This study explores a novel dual‐binder system, termed the “bollard hitch” model, designed to overcome these limitations as the first PTFE‐less binder for binder fibrillation. Poly(acrylic acid)‐grafted sodium carboxymethyl cellulose (PC) acts as the “bollard,” strongly attaching to the PTFE “anchor.” This binder system reduces PTFE usage by over 70% and enables the fabrication of high‐mass loading cathodes (up to 90 mg cm − 2 , 15.6 mAh cm − 2 ) with superior performance. It enhances ionic conductivity and mechanical strength, making it suitable for high‐voltage applications and offering great potential to revolutionize the manufacturing of high‐performance, durable energy storage systems.