The objective of Inno-SE is to build a bridge between knowledge institutions and companies in an effort to meet the energy political objectives; while at the same time, growth, innovation and occupation are created within energy efficiency and intelligent energy systems. The network project is divided into several focus areas. This part concerns energy storage, where AAU is focus area leader. First and foremost, focus is on technological challenges and potential of optimization, which lie in the direct or indirect storage of energy, but also the societal challenges related thereto. This energy storage is essential in a fossil free energy system.