Effect of Solid Polymer Electrolyte Based on Corn Starch and Lanthanum Nitrate on The Electrochemical Performance of Supercapacitor

Energy storage devices are crucial for reducing the consequences of intermittency. The supercapacitor is a promising energy storage device with outstanding properties such as high power density and long cycle life. A supercapacitor needs an electrolyte. We use solid polymer electrolyte (SPE) due to its safety, such as no leakage and no flammability. However, SPE has low ionic conductivity. The ionic conductivity of SPE can be improved by incorporating corn starch together with lanthanum nitrate (La(NO3)3) as additional materials in solid polymer electrolytes using the solution casting method. The SPE is then fabricated into a supercapacitor. The results of XRD characterization show that the 8wt.% concentration is increasingly amorphous characterized by a low degree of crystallinity value of 22.20%The electrochemical performance of the supercapacitor has been thoroughly investigated. The experimental results showed that the addition of 8 wt.% exhibits a suitable SPE for a supercapacitor. By electrochemical impedance spectroscopy (EIS) at room temperature, the maximum ionic conductivity of supercapacitor is 9.68 x 10^-11 S/cm. The maximum specific capacitance from cyclic voltammetry is 2.71 x 10^-7 F/g at a scan rate of 50 mV/s. The highest energy density and power density from galvanostatic charge-discharge are 0.032 Wh/kg and 3,402.13 W/kg. This research provides valuable insights for the further development of energy storage technology.