Coir Pith Derived Bio-carbon: Demonstration of Potential Anode Behavior in Lithium-ion Batteries

Microporous bio carbon derived from coir pith has been evaluated for the first time for its suitability as anode material in lithium-ion batteries. Coir pith, used generally to fire bricks is well known for its carbon rich composition arising from three different carbon sources, viz., cellulose, lignin and organic carbon. As a result, preparation of bio carbon containing amorphous and disordered carbon along with the co-existing graphitic characteristics from coir pith appears to be a potential approach and deserves to be explored further. Coir pith derived carbon (CPC) generated through an eco benign and economically viable carbonization process was activated with KOH at temperatures such as 800, 850 and 900° C to obtain the desired microporous nature, especially due to the dissolution of lignin in alkaline solution. Pristine CPC, activated at 850 °C in particular, upon investigation as anode in LIB applications exhibits a steady state progressive capacity of 837 mAh g−1 at 100 mA g−1 condition upon extended cycles. The study demonstrates the suitability of pristine CPC anode up to 5.4C rate with an acceptable capacity behavior and appreciable retention capability. The currently discussed waste-to-wealth attempt involves a cheap and scalable process, besides qualifying pristine CPC-850 as an energy efficient anode for LIB applications.