The Effect of KOH Activator Concentration upon the Characteristics of Biomass-Derived Water Hyacinth Process on Lithium-Ion Capacitor

Lithium-ion capacitors (LIC) is believed to be an ideal option in certain application as energy storage device due to its properties either possessing high energy density (four times higher than electrical double-layer capacitor) or having as much power density as a supercapacitor. In this study, a biomass-based activated carbon (WHAC) was prepared by using the water hyacinth plant through the activation process utilizing a chemical activating agent, KOH. The water hyacinth was carbonized at 500 °C for a 1 h holding time with a ramping temperature of 10 °C/min. Then, the LICs electrode is constructed by two different types of electrode, WHAC as the main active material of cathode and lithium titanate oxide (LTO) for the anode. The biomass-derived activated carbon exhibits a high specific surface area of 791.8 m2/g and a high pore volume of 1.13 m3/g. The assembled LiCs shows a reasonable electrochemical performance with a maximum specific capacitance of 1.12 F/g with the highest specific energy of 4.48 Wh/kg and specific power of 34.14 W/kg. This LIC cell is one of the promising candidates for future applications due to its low-cost materials and owns more advantages than typical Lithium-ion Batteries (LIBs).