Hard carbon (HC) has been a major focus of recent research on sodium-ion battery (SIB) anodes. However, its practical application is limited by suboptimal preparation techniques, limited exploration of sustainable precursor sources, and cost constraints. In this study, we optimized the physicochemical, electrochemical, sustainable, and technoeconomic performance of SIB anodes using HC derived from oil palm trunk (OPT) biomass via hydrothermal carbonization (HTC), ball milling, and pyrolysis. Among the ten tested samples, the HTC sample prepared at 250 °C for 24 h presented the best properties: an ID/IG ratio of 0.9545, a specific surface area of 57.07 m2/g, a total pore volume of 0.5876 cm3/g, an average pore size of 2.05 nm, a stirring effect, an improved morphology, and the highest carbon content (96.51%). The best electrochemical performance was demonstrated for the HTC sample stirred at 250 °C for 24 h, with a specific capacity of 343 mAh/g at 0.1 C, a capacity retention of 301 mAh/g after 300 cycles, and an initial Coulombic efficiency of 83%. These findings indicate that the temperature and duration of HTC synergistically enhance the physicochemical and electrochemical properties of HTC. The life cycle assessment revealed that the multistep method effectively reduced the environmental impact. Finally, a technoeconomic analysis confirmed the cost efficiency and scalability of the coin cell batteries. © King Fahd University of Petroleum & Minerals 2025.