Blending of Activated Low-Grade Coal Powder with Coconut Shell Waste for Supercapacitor Applications

Abstract

Activated carbons (ACs) are the key components for supercapacitors due to their several advantages including abundant availability, low cost, ease of fabrication, and controllable physicochemical properties. In recent times, the investigation on the relationship between supercapacitor performances and the morphology, texture, and dimensions of different types of activated carbons is becoming essential to optimize the best energy storage devices. The main objective of the current study is to create an improved activated carbon material by blending low-grade coal powder (subbituminous rank available in Northeast India) and waste coconut shell-based activated carbon at different weight ratios to use as indigenous supercapacitor electrode materials. The mixed-blend improved ACs exhibit excellent electrochemical performance (specific capacitance of 251.67 F g −1 at 0.5 A g −1 ) as compared to the commercially available AC sample. The prototype supercapacitor (45.6 cm 2 pouch cell configuration) fabricated by using the blended coal-and coconut shell-based activated carbons shows an estimated capacitance of ∼30 F at 2.7 V in an organic electrolyte (1.5 M TEABF 4 in ACN) with cellulose paper-based separators (TF40-30; NKK). It was also observed that the fabricated prototype supercapacitor is capable of lighting an LED (32 mW) for an entire hour, demonstrating a promising future in high-performance and low-cost energy storage technologies.

Quantum Capacitance of Two-Dimensional-Material-Based Supercapacitor Electrodes

“…Among the SC electrode materials, the mostly studied and even commercially used materials (e.g., activated carbon) are carbon-based materials. − The reason behind this is, as the activated carbon stores the charge via a EDLC (a physical mechanism) and, hence, better power density, cycle life, and chemical stability can be obtained, surface morphology and porosity can be tailored. Carbon-based materials offer certain benefits, such as having different dimensionality [from zero-dimensional (0D) to three-dimensional (3D)], and their optical, electrical, mechanical, biocompatible, and other properties can be effectively controlled. , The main carbon nanostructures discussed in this section are graphene, carbon nanotubes (CNTs), graphyne, etc.…”

Waste plastic to energy storage materials: a state-of-the-art review

“…Commonly used materials for supercapacitors are porous carbon-based materials, such as activated carbon, carbon nanotubes, graphene, etc., made from low-grade sub-bituminous coal, coconut shell powder, 75 and mung bean husks. [76][77][78]79 In order to show the superiority of porous carbon materials derived from waste plastics, Table 4 lists the recent advances in supercapacitors.…”