RECENT ADVANCES AND CHALLENGES OF CURRENT COLLECTORS FOR SUPERCAPACITORS

Global energy and environmental issues are driving the development of modern advances in efficient and environmentally friendly energy storage systems. Such systems must meet a range of requirements, which include high energy and power density, long service life, flexibility, industrial scalability, security and reliability. Progressive achievements in the field of energy storage are associated with the development of various kinds of batteries and supercapacitors. Supercapacitors are state-of-the-art energy storage devices with high power density, long lifespan, and the ability to bridge the power/energy gap between conventional capacitors and batteries/fuel cells. However, supercapacitors have limitations associated with low energy density, which can be solved by using various types of current collectors, since current collectors are one of the main massive components of supercapacitors. This review gives a complete understanding of the effect of current collectors on the actual performance and properties of supercapacitors. We reviewed current collectors based on carbon and metal-containing materials, and supercapacitor configurations to identify possible improvements in electrochemical performance in terms of specific capacitance, energy density, power density, service life and variability in their application

Investigations of Activated Carbon from Different Natural Sources for Preparation of Binder-Free Few-Walled CNTs/Activated Carbon Electrodes

In this study, we present another approach to fabricating high-performance supercapacitor electrodes by combining activated carbon particles with carbon nanotubes (AC/CNT). We synthesized activated carbon from diverse biomass sources using a carbonization process and chemical activation with KOH. By incorporating carbon nanotubes, we significantly augmented the electrode’s surface area, resulting in exceptional ion transport and a substantial increase in specific capacitance. Our investigation reveals that the optimized composition, 85:10:5 of AC, CNT, and conductive additive, achieved outstanding specific capacitance values, notably 125.6 F g−1 at 1 mV s−1 and 118 F g−1 at 1 A g−1, along with a maximum energy density of 4 Wh kg−1. Electrochemical impedance spectroscopy (EIS) further demonstrated the superior charge transfer capabilities of these electrodes, notably at a frequency range from 100 kHz to 10 mHz. Additionally, our research highlights the influence of different biomass precursors, such as apricot kernels, walnut shells, and rice husks, on the electrochemical behavior of these electrodes. Overall, this study provides valuable insights into the development of high-performance supercapacitors, emphasizing the potential of diverse biomass sources in optimizing electrode materials