An overview of electrochemical supercapacitators (ES), this book summarizes the fundamental sciences involved in ES operation and the technological developments in materials science and engineering for materials fabrication. The book also provides a deep analysis of their integration with primary power systems and their benefits towards current applications. The coverage of the materials, system design, and related issues for the development of supercapacitators will be useful to readers in selecting existing materials and technologies and developing new materials and technologies to improve supercapacitor performances.