Investigations on Acid Doped Poly Acrylamide Based Gel Electrolytes for Supercapacitor Applications

Abstract

Effects of acid dopants on polymer gel electrolytes for Electric double layer capacitors or super capacitors
are reported in this work. Flouroboric Acid (HBF4), Para-toluene sulphonic acid (PTS) and perchloric acid (HClO4) are
doped in the polymer network of Acrylamide and thin films which are made by solution casting technique. The physical
characterization of the gel is done using FT-IR, SEM and thermal analysis while the electrochemical parameters of the
super capacitor are evaluated by A.C. Impedance spectroscopy, Cyclic voltammetry and Galvanostatic charge discharge
test in the potential range of 0 to 1 V. The conductance of the gel is found to be in the order of 10-3
to 10-4
S/cm. The
EDLC with HClO4 dopant has better electrochemical stability than the EDLC comprising poly (AAm – HBF4) gel and
poly (AAm - PTS). This is due to the enhanced ability of trapping HClO4 in its matrix and this system can be a better
system of EDLC with high specific capacitance, high rate capability, cycling life upto a maximum of 103
cycles with good
coulombic efficiency and minimum IR losses. The EDLC with PAAm – HClO4exhibits highest power density (181 W/Kg)
and energy density (2 Wh/Kg) compared to other HBF4 and PTS doped polymer gel electrolytes.This clearly
demonstrates that HClO4 doped gel electrolyte is a better candidate for supercapacitor applications.