Sustainable manufacturing of graphitic carbon from bio-waste using flash heating for anode material of lithium-ion batteries with optimal performance

To address the fundamental challenge of resource sustainability and to effectively deal with issues pertaining to supply chain resilience, cost efficiency, environmental impact, and the ability to meet specific local needs; there is an urgent need for high-grade battery anode materials produced locally from readily available raw materials. In this work, synthesis of high-quality graphitic carbon (GH) derived from human hair is demonstrated using an in-house engineered reactor based on Joule's Flash heating method. The GH is characterized using various techniques to examine its chemical composition, particle morphology, crystallinity, and demonstrate its usability as an anode material for lithium-ion batteries. Fabricated coin cell with active material exhibits a gravimetric capacity of 320 mAh g−1 at a current density of 30 mA g−1 (equivalent to a C rate of ≈0.1C) over the 100 cycles. The in situ and ex situ studies using XRD, Raman, XPS, and UPS techniques conclude that during the initial charge cycle for GH, lithium ions diffused into the electrode during the resting period are effectively removed. This not only improves the lithium inventory to start with but also mitigates subsequent solvent degradation during solid electrolyte interphase (SEI) formation. Thus, these improvements ultimately enhance the capacity of the anode to 500mAh g−1 at a current density of 20 mA g−1. The study offers the potential to initiate a new realm of research by redirecting the focus to a material once considered as mere waste.