Ternary composite of PANI, CuO and ZnO in its standardized weight composition of PANI54. 55%: CuO36. 36%: ZnO9. 09% (PCZ9) was synthesized by in-situ single-step chemical method to study the supercapacitance of it and its binary composites. An aqueous supercapacitor cell of PCZ9 provided specific energy (E) higher than that of vanadium flow batteries and as close as to that of Pb-acid batteries, which is 27 W h kg−1 with the specific power (P) of 0. 6 kW kg−1 at 1 A g−1, mainly inflicted by H+/NH₄^+ ions co-intercalation/de-intercalation. While, an organic asymmetric supercapacitor cell made up of an binary composite of PCZ9, which is CuO80%: ZnO20% (CZ) provided E higher than that of Pb-acid batteries, Ni–Cd batteries, Ni-MH batteries, Na-metal chloride batteries and Na-S batteries, which is 71 W h kg−1 with the P of 0. 232 kW kg−1 at 0. 1 A g−1. Most importantly, the organic asymmetric supercapacitor continued to provide higher E up to the current density of 2 A g−1, as a trait of its excellent rate capability. In addition, both the aqueous symmetric and organic asymmetric supercapacitors exhibited promising durability by retaining 58. 11 and ~ 75% of their initial energy up to 5000 cycles and 2500 cycles, respectively, when subjected to durability test at 0. 4 V s−1 and 1 A g−1 (at different temperatures), respectively. The high E of the aqueous symmetric supercapacitor cell of PCZ9 was demonstrated by making it to exhibit its power backup ability, when, the PCZ9 symmetrice cell provided 1 min. and 30 sec. of power backup for 1 min. of charging using the 1. 5 V AA battery of Duracell, establishing its high energy character.
Viswanathan et al. (Thu,) studied this question.