Development of nitrogen-doped carbon aerogel-based 60 Farad, 4.5 kJ supercapacitor module

Among various nano-forms, carbon being explored as electrode materials for supercapacitor, carbon aerogels (CA) manifest several excellent features owing to their 3D interconnected mesoporous structure, high surface area and good electrical conductivity. With an objective for further enhancement of its efficacy, CA doped with nitrogen was synthesized using solvo-thermal gelation of resorcinol, melamine and furfuraldehyde in isopropyl alcohol medium at 130°C and ~20 bar. Based on the earlier detailed investigation, ~10.6 at.% of nitrogen-doped CA (N–CA) that exhibits the highest specific surface area and mesopore surface area was used for the fabrication of supercapacitor. Further, synergetic effect of the improved wettability due to inclusion of heterogeneous species, increased conductivity due to incorporation of graphitic nitrogen and high content of pseudocapacitive pyridinic as well as pyrrolic nitrogen in the carbon network, resulted high specific capacitance of ~218 F g⁻¹. The N–CA-based supercapacitor (SC) module was fabricated with 18S-2P cell configuration with cell capacitance of ~450 F. Using international testing standards IEC/EN 62391, overall capacitance of ~61.8 F at 12.5 V operation containing total energy storage of ~4.5 kJ with low equivalent series resistance (ESR) of ~5.5 mΩ was achieved for the fabricated SC module. These parameters are comparable to the similar module of Maxwell Inc. The module has been demonstrated for cranking a car engine of 998 cc and a current of ~208 A was drawn at the time of ignition.