Boonnun S.Chaison P.Meekati T.Poochai C.Pon-On W.Amornsakchai T.Sodtipinta J.Mahidol University2025-10-042025-10-042025-11-30Journal of Energy Storage Vol.137 (2025)https://repository.li.mahidol.ac.th/handle/123456789/112436This research examines the use of an agricultural waste as an economical carbon precursor to produce high-performance electrodes in energy storage applications. The significance of such materials lies in their technical relevance owing to their abundance, easy accessibility, and economic viability. In this study, the preparation process and characterization of carbonaceous material derived from pineapple stem starch, specifically high-amylose starch, was thoroughly examined. The resulting carbonaceous material, SAC-800, exhibited a specific capacitance of 374 F g⁻¹ at 0.1 A g⁻¹ and 86 F g⁻¹ at 5 A g⁻¹, showcasing a high-rate capability. This superior performance stems from KOH-induced chemical activation, leading to the development of expanded micropores and resulting in a significantly high surface area, 2796 m² g⁻¹. Moreover, the material had surface oxygen species, facilitating excellent ion interaction with the electrolyte solution. Consequently, the specific capacitance remains relatively high. When subjected to cycling tests at 3 A g⁻¹ for 12,000 cycles, it demonstrates promising results, maintaining 91 % of its initial capacitance in a 1 M H<inf>2</inf>SO<inf>4</inf> electrolyte. The sustainable source material and straightforward synthesis make the electrode a cost-effective, high-performance, and durable option for electrochemical energy storage systems. The developed electrode is a cost-effective and sustainable option for electrochemical energy storage systems with a straightforward synthesis and high durability.EnergyEngineeringArticleSCOPUS10.1016/j.est.2025.1185542-s2.0-1050172343022352152X