EDLC performance of plasticized NBG electrolyte inserted with Ba(NO3)2 salt: Impedance, electrical and electrochemical properties

Abstract

The great challenge in front of energy storage devices is to reduce the microplastics in the ocean and their potential harm to human health through drinking. The microplastics topic mainly results from the increasing usage of electronic devices and their components. Developing green electrolytes based on natural polymers and plasticizers is unique in overcoming microplastic issues. Natural beef gelatin (NBG) based plasticized polymer electrolyte films doped with barium nitrate (Ba(NO3)2) and glycerol (Gly) were fabricated using a solution casting process. The NBG electrolyte containing 12 wt.% Ba(NO3)2 and 50 wt.% Gly-has the maximum ionic conductivity, 4.87 × 10−5 S cm−1, at room temperature. The electrochemical performance of plasticized NBG:Ba(NO3)2 was examined utilizing impedance spectroscopy, with an emphasis on the dielectric characteristics and electric modulus parameters. With electrochemical stability up to 2.65 V, the plasticized specimen with the highest conducting demonstrated eligibility for use in energy storage devices. Transference number measurement (TNM) proved the dominancy of ions as a charge carrier in the plasticized NBG:Ba(NO3)2 system, yielding an electron transference number of 0.045 and an ion transference number of 0.955. The absence of redox peaks in the cyclic voltammograms suggests a capacitive charge accumulation in the plasticized electrolyte near to the electrode surface other than the Faradaic process. The triangle-shaped galvanostatic charge-discharge (GCD) plot shows a comparatively low drop voltage. The constructed electric double layer capacitor (EDLC) using activated carbon displays energy and power densities of 3.41 W/kg and 336.4 Wh/kg, respectively, at the first cycle. The EDLC performances of plasticized NBG:Ba(NO3)2 demonstrated the cell has potential industrial use as an energy storage device.