Executive Summary : | Energy is a crucial component in human life, and research is being conducted to develop more efficient, long-lasting, and safe alternative energy storage systems. Electrochemical energy systems, including batteries, fuel cells, electrolytic capacitors, and supercapacitors, are being developed to meet rising energy needs and environmental concerns. Supercapacitors are increasingly valuable due to their quick charge/discharge characteristics, high power density, extended cycle life, low cost, and environmental friendliness. They are classified into three categories: electric double layer capacitors (EDLCs), pseudocapacitors, and hybrid supercapacitors. EDLCs accumulate charge at the interface of electrolyte and electrode, while pseudocapacitors involve faradic redox reactions in active materials. Carbon-based materials are suitable for EDLC due to their large specific surface area, high conductivity, light weight, high thermal and chemical stabilities, and flexible nature. Hybrid capacitors are expected to enhance electrode performance for supercapacitor applications, with three types: composite hybrid, asymmetric, and battery type. The composite hybrid supercapacitor using MXene-based composite is expected to possess excellent electrochemical characteristics, including energy/power density, rate capability, and cycle stability. |