Hierarchical SnO₂-Graphite Nanocomposite Anode for Lithium-Ion Batteries through High Energy Mechanical Activation

Development of novel electrode materials with unique architectural designs is necessary to attain high power and energy density lithium-ion batteries (LIBs). SnO₂, with high theoretical capacity of 1494 mAh g⁻¹, is a promising candidate anode material, which has been explored with various strategies, such as dimensional reduction, morphological modifications and composite formation. Unfortunately, most of the SnO₂-based electrodes are prepared by using complex chemical synthesis methods, which are not feasible to scale up for practical applications. In addition, concomitant irrecoverable initial capacity loss and consequently poor initial Coulombic efficiency still persistently plagued these SnO₂-based anodes. To overcome hitherto conceived irreversible formation of Li₂O by conversion reaction, to fully harness its theoretical capacity, this work demonstrates that a hierarchical structured SnO₂-C nanocomposite with 68.5% initial Coulombic efficiency and reversible capacity of 725 mAh g⁻¹ can be derived from the mixtures of SnO₂ and graphite, by using low cost industrial compatible high energy ball milling activation.