Synthesis and Adhesive Properties of Polyoxamides for Binder Application of Lithium Ion Battery

Abstract

[Notes] We synthesized polyoxamides ( PX ) using various diamines and diphenyl - oxalate ( DPO ) and investigated their molecular weight, copolymer composition, thermal properties, mechanical properties, swelling behavior for electrolytes of lithium ion batteries ( LIB ) and adhesive properties with electrodes of LIB. We established a new method to synthesize PX with high molecular weight by using N - methylpyrrolidone as a synthesis solvent, setting temperature to 200 ° C and devising the order of charging diamine and DPO. All PXs synthesized in this study were crystalline polymers, harder than polyvinylidene - di - fl uoride ( PVdF ) and had smaller elongation than PVdF. Both, the saturated swelling ratios of PX for electrolytes of LIB and the changes in mechanical properties due to swelling were small. We found in this study that the adhesive properties of PX copolymers composed of 1,3 - bisaminomethylcyclohexane and hexamethylenediamine on both cathode and anode were good, but they were inferior to that of PVdF.