Pencil lead based low cost and binder-free anode for lithium-ion batteries: effect of different pencil grades on electrochemical performance

Abstract

We depict a facile and one step approach to fabricate a high capacity anode by drawing pencil lead onto the current collector. For efficient loading and adhesion, stainless steel substrate used as a collector is roughened using sand paper before drawing the pencil lead onto it. As pencil lead comprises graphite-clay (primarily silica) composites, graphite provided cyclic stability due to lithium ion intercalation while SiO2 resulted in higher reversible capacity by facilitating alloying and de-alloying of lithium with silicon. To evaluate their role further onto the anodic performance, three different pencil grades (4H, 4B and 10B) are used which varied in graphite and silica composition. A detailed comparative analysis of their electrochemical performances is done and is further correlated to their structural parameters. Importantly, the fabrication of anode is not only facile but also is solvent and binder free and is also scalable for real application.Graphic Abstract