This book is one of the "High Performance Polymer Materials Series", a key publication project of the "13th Five-Year Plan". As a typical electrochemical energy storage device, batteries have received much attention and focused research. This book combines the fundamentals of materials science and electrochemistry to systematically describe the characteristics of positive and negative materials and their electrochemical responses for ion batteries, supercapacitors, air batteries, fuel cells, solid-state batteries and other types of batteries. Important elements such as electrolyte and diaphragm materials are also described in detail. In addition, the book focuses on the engineering application technology of energy cells, considering the factors that affect the operating performance of energy cells, the design of battery packs and the existing battery standards. The book is divided into four main sections: preparation, characterisation and electrochemical behaviour of battery materials, electrode materials for high performance batteries, electrolyte and diaphragm materials for high performance batteries, and predictive evaluation of battery performance and application technologies. The most distinctive feature is the combination of basic knowledge and fundamental principles of energy batteries with the latest scientific research results, with special emphasis on the academic contributions in the field in the last decade.