This practical textbook and reference work vividly illustrates the world of electrochemical energy converters and their modern applications for sustainable energy concepts. How can excess wind and solar energy be stored, and how can hydrogen from non-fossil resources be utilized as a chemical storage form? Each topic area addresses the physical, chemical, engineering, and materials science fundamentals, allowing for an interdisciplinary perspective on technical applications. An overview of the legal framework provides reliable information on legal issues. For the second edition, numerous reader comments were taken into account, leading to the revision and expansion of many chapters. The legal foundations have been thoroughly updated according to the state of legislation as of March 2018.