This thesis focuses on the synthesis and characterization of various carbon allotropes (e.g., graphene oxide/graphene, graphene foam (GF), GF/carbon nanotube (CNT) hybrids) and their composites for electrochemical energy storage applications. The coverage ranges from materials synthesis to electrochemical analysis, to state-of-the-art electrochemical energy storage devices, and demonstrates how electrochemical characterization techniques can be integrated and applied in the active materials selection and nanostructure design process. Readers will also discover the latest findings on...