Electrochemical Characteristics Study Of Hydrogel Supercapacitor Electrolyte Containing Redox Addictives

Hydrogel electrolyte is an important component of solid-state supercapacitors.In this paper,a novel double-network hydrogel electrolyte with better electrochemical and mechanical properties is prepared.The main research results are as follows:1.The new type of solid electrolyte preparation methods of PVA-PAA double-network hydrogel is proposed,and tested by FTIR test,SEM test,mechanical test and electrochemical experiments which include CV test,CP test,EIS test and cycle stability test,proved that the PVA-PAA double-network hydrogel has good electrochemical properties and mechanical properties,its characteristic is a combination of PVA hydrogel good mechanical properties and PAA hydrogels high water content and electrical conductivity,when the concentration of PVA and PAA polymer matrix ratio is 1:1,the mechanical and electrochemical properties of PVA-PAA double-network hydrogel is optimized.2.Based on the preparation of PVA-PAA double-network hydrogel,by adding a small amount of aluminum ions,using hydrogen bond and ionic bonding between aluminum ion and COO-group dual functions,the preparation of a new type of PVA-PAA-Al double-network hydrogel is proposed.In the case of electrochemical performance is not affected,the mechanical performance was better than ordinary PVA-PAA hydrogel,and have self-healable ability.When the addition amount of aluminum ions is 0.1mmol,the PVA-PAA-Al double-network hydrogel has the most suitable mechanical tensile properties and the best self-healable properties.3.In order to further improve the energy density and specific capacitance,based on previous studies,adding KI as redox additives,the preparation of PVA-PAA-KI double-network hydrogel,at the same current density,the supercapacitor capacitance value increased by 75.6%,the energy density of 75.6%,and shows good cycle stability,embodies the PVA-PAA double-network hydrogel improvement potential of electrochemical performance.