Polyimide Binder Composition for Low-Temperature Battery Manufacturing

The patent changes the chemical composition parameters of the binder system by introducing a polyol component with specific functional groups (carboxyl, hydroxyl, or amine groups) that can react with polyamic acid. This compositional parameter change enables the conversion reaction to proceed at lower temperatures (below conventional curing temperatures), thereby resolving the contradiction between achieving good cycle characteristics and reducing manufacturing cost/process complexity.

The polyol component acts as a chemical intermediary that facilitates the conversion of polyamic acid to polyimide at lower temperatures. The polyol's functional groups mediate the reaction process, allowing the transformation to occur under milder heating conditions than conventional methods, thus reducing manufacturing cost while maintaining battery reliability.

By changing the chemical parameters of the binder composition (adding polyol with reactive functional groups), the patent enables the formation of strong polyimide bonds at lower temperatures. This parameter change allows the binding process to be completed more quickly and with less energy, thereby improving production efficiency while maintaining adequate mechanical strength.

The patent replaces the conventional thermal-mechanical curing process (which requires prolonged high-temperature exposure) with a chemical reaction process driven by polyol-polyamic acid interaction. This substitution of the curing mechanism enables bond formation at lower temperatures and shorter times, improving productivity without sacrificing mechanical strength.

The patent changes the energy parameter of the curing process by introducing polyol chemistry that enables low-temperature reaction. The functional groups in polyol (carboxyl, hydroxyl, or amine groups) form reactive intermediates with polyamic acid that lower the activation energy required for polyimide formation, thus reducing energy consumption while maintaining binding strength.

The patent converts the typically harmful effect of requiring high energy input into a benefit by using the polyol's functional groups to create a self-reacting system. The chemical reactivity of polyol functional groups naturally drives the conversion at low temperatures, turning what would be an energy-intensive thermal process into a chemically-driven low-energy process that maintains adequate binding strength.