Core-Shell Fluororesin Binder Particles for Electrode Adhesion

The patent changes the chemical composition parameters of the shell layer from conventional non-fluorinated resin to specific acryl-based polymers (polyacrylic acid, polyacrylamide, polyvinyl alcohol, or carboxymethyl cellulose) with defined molecular weights and degrees of substitution. This parameter change enables the shell to provide both desired surface properties and sufficient adhesive strength to electrode active materials, resolving the contradiction between ease of manufacture and adhesive strength.

The patent creates a composite core-shell structure where a perfluorinated resin core (providing dispersibility and electrochemical stability) is combined with a specifically engineered acryl-based polymer shell (providing complete coverage and uniformity). The shell materials are selected and formulated to ensure complete encapsulation of the core, achieving both improved dispersibility and uniform shell formation, thus resolving the contradiction between stability and manufacturing precision.

The patent applies local quality by concentrating the binding function in the acryl-based polymer shell layer while the perfluorinated resin core provides dispersibility. The shell layer, comprising specific acryl-based polymers with controlled molecular weights and functional groups, is designed to provide strong adhesive properties locally at the particle surface, enabling effective binding of electrode active materials even when the overall content of core-shell particles is reduced. This localized functional differentiation resolves the contradiction between quantity and strength.