Storage of energy is considered as the most germane technologies to address the future sustainability. In this study, aniline was chemically oxidized with a controlled concentration of pyrelenediimide tetracarboxylic acid (PDITCA) by ammonium persulfate to polyaniline salt (PANI‐H2SO4‐PDITCA), with nanorods morphologies, having a sensibly decent conductivity of 0.8 S cm−1, wherein H2SO4 was generated from ammonium persulfate during polymerization. PANI‐H2SO4‐PDITCA salt showed bathochromic fluorescence shift (595 nm) compared to PDITCA (546 nm). The Brunauer–Emmett–Teller surface area of the PANI‐H2SO4‐PDITCA‐25 and PANI‐H2SO4‐PDITCA‐50 were 18.3 and 21.4 m2 g−1, respectively. Furthermore, its energy storage efficiency was evaluated by supercapacitor cell configuration. The composite PANI‐H2SO4‐PDITCA‐50 showed capacitance 460 F g−1 at 0.3 A g−1 and large cycle life 85,000 cycles with less retention of 77% to its original capacitance (200 F g−1) even at a better discharge rate of 3.3 A g−1. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45456.