Journal of Scientific Engineering Advances

Abstract

Oil-palm processing generates lignocellulosic residues that are commonly used for low-value combustion, mulching, or other bulk applications but increasingly represent promising precursors for advanced carbon electrodes. This critical qualitative literature review examines the conversion of palm kernel shell, empty fruit bunch, mesocarp fibre, oil-palm frond, and related residues into porous carbon for supercapacitors and hard carbon for sodium-ion batteries. Rather than treating biomass-derived carbon as a single material class, the review develops a feedstock–processing–microstructure–performance framework showing that the optimum carbon architecture depends fundamentally on the intended charge-storage mechanism. Supercapacitors generally benefit from accessible hierarchical porosity, electrolyte wettability, heteroatom functionality, conductivity, and short ion-transport pathways. Sodium-ion battery anodes require a different balance involving suitable turbostratic interlayer spacing, controlled defects, limited reactive external surface, stable solid-electrolyte interphase formation, and appropriately developed closed pores. Aggressive activation therefore creates a central engineering paradox: it can increase capacitance while simultaneously worsening irreversible sodium consumption and initial Coulombic efficiency. Recent palm-derived materials demonstrate that oil-palm residues can support both technological pathways when processing is application-specific. However, translation requires standardized characterisation, realistic mass loading, full-cell testing, carbon-yield reporting, chemical recovery, life-cycle assessment, and integration with palm-oil mills. A technology-selection framework is proposed to match feedstock characteristics and processing intensity with the most appropriate electrochemical application.