State-of-the-art materials for high power and high energy supercapacitors: Performance metrics and obstacles for the transition from lab to industrial scale - A critical approach

The growing field of supercapacitors has already gained enough maturity and complexity to be the object of highly specific reviews. This review aims to provide a comprehensive outline of the topic, by presenting the state-of-the-art electrolytes and electrode materials used in supercapacitors as well as the relationship between their intrinsic features and their key performance indicators. This analysis is complemented by numerous examples of recent literature-reported performances of hybrid supercapacitors. To aid comparison, these are listed in tables and shown in plots, organized by type of electrode material and by type of electrolyte. Finally, performance differences between lab scale and commercial scale devices are put in perspective, by exploring, on one hand, the obstacles to the transition from promising lab scale to industrial scale devices and by explaining, on the other hand, the reasons why the same type of electrode material and electrolyte combination often perform more poorly in real-world devices. With this approach, the authors expect to give a useful insight (and a comprehensive snapshot) into the challenges that need to be surpassed to bridge the gap between lab scale and industrial scale devices.