The growing energy demand has underscored the importance of sustainable energy storage devices. Biomass-derived carbon dots (B-Cdots) have gained significant attention for their potential to address this challenge. Utilizing greener routes for the large-scale synthesis of B-Cdots is not only eco-friendly and cost-effective but also promotes sustainability. This review highlights various synthesis methods for B-Cdots, including microwave-assisted, hydrothermal, and pyrolysis-based carbonization processes. It also explores their electrochemical applications in supercapacitors, lithium-ion batteries, sodium-ion batteries, and other energy storage devices, along with recent advancements in the field. The fabrication of electrodes using B-Cdots offers several advantages, such as tunable chemical and physical properties, porous structures, efficient heteroatom doping, and excellent electrical conductivity. These attributes make B-Cdots highly attractive for energy storage applications. Overall, this review emphasizes the critical role of sustainable materials in shaping the future of energy storage technologies.