Lavender-powered batteries stabilized with new ‘priming’ technique

An international research team has developed a novel, cost-effective sodium-ion battery (SIB) using hard carbon derived from lavender flower waste as the anode material, addressing sustainability and performance challenges in energy storage. Lavender agricultural residue, previously underutilized, was converted into hard carbon while preserving its natural microstructure, which enhances electrolyte penetration and sodium ion diffusivity, thereby improving battery efficiency. The lavender-based anode was paired with a nickel-doped P2-type cathode (Na0.67Mn0.9Ni0.1O2), where nickel incorporation improved electronic conductivity and structural stability. Electrochemical testing showed promising capacities with the cathode achieving 200 mAh/g (42% retention after 100 cycles) and the anode 360 mAh/g (67.4% retention after 100 cycles), demonstrating the potential of plant-derived hard carbons as sustainable, economical battery materials. A key challenge addressed was the inherent sodium deficiency in bio-based materials, which the team overcame by