ABSTRACT
An introductory chapter is a good way to start a technical book. It provides a broad overview of the field, announces the general intention of the authors, describes the structure of the book, and outlines its contents. It should not be taken, however, as a mere summary or a highlight instrument-after all this is certainly not an executive summary. Instead, we believe this introduction could go beyond the conventional goals mentioned above and provide also an account of the reasons why it is worth working on energy materials, a vision of how research and development can contribute to the due re-evolution towards a sustainable model of generation, storage, distribution, management and consumption of energy and a hint of what are the major scientific, technical and social challenges ahead.
