This book provides a comprehensive account of the fundamental aspects of electrochemical energy storage devices, with a focus on electrochemical supercapacitors. Building from an in-depth knowledge of the present state of energy utilisation, contextualised against the requirement for renewable energy, the book sets out the components and performance-governing parameters of conventional and supercapacitors, identifying the challenges, trends and limitations involved in their implementation. Accessible and authoritative, this book is ideal for undergraduates, postgraduate students and research scholars, as well as industry professionals working in energy, nanoscience, material science, and the automobile industry for e-vehicles. Key Features: Each chapter contains a table comprising performance parameters of the device Provides fundamental electrochemical properties of material and performance parameters for energy storage devices Includes requirement, characteristics, classification and recent trends in electrode materials for supercapacitors Summarizes formation of material by various methods Provides a broad insight of energy storage devices for future technological applications