Development and Optimization of Photopolymerizable Binders for Lithium-Ion Battery

Abstract

The demand for faster, energy-efficient, and cost-effective lithium-ion battery (LIB) manufacturing has necessitated innovations in electrode binder technology. Conventional binders such as PVDF (polyvinylidene fluoride) and SBR-CMC (styrene-butadiene rubber and carboxymethyl cellulose) require prolonged thermal curing processes, contributing significantly to production time and energy consumption. This study introduces a novel photopolymerizable binder system based on N-Phenylmaleimide copolymerized with 4-Styrenesulfonic acid sodium salt hydrate (4SN), N-Phenyl-p-phenylenediamine (NPN), and 5-Aminoisophthalic acid (5AN), initiated by a BAOP Phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide -based photoinitiator. The synthesis, UV-curing process, and application on aluminum current collectors are detailed. Binder-coated electrodes were cured under 365 nm UV light and subjected to minimal thermal treatment. The resulting electrodes were evaluated against conventional PVDF-based electrodes using FTIR, SEM, peel adhesion tests, potentiometric analysis, and comprehensive electrochemical characterization including cyclic voltammetry and charge-discharge cycling. The UV-cured binders demonstrated enhanced adhesion, efficient polymerization, reduced processing time, and competitive electrochemical performance, highlighting their potential for scalable LIB production