Abstract

Energy storage systems presently pose a bottleneck to the fast-growing and wearable flexible technologies. Some commercialized wearable devices, such as the Apple iWatch and Google Glass, remind scientists and engineers about the prominence of ongoing research exploring lightweight wearable materials in flexible device applications. This chapter covers a fundamental concept of various types of energy storage devices. It focuses on the recent advancements in energy storage materials that can deliver stable electrochemical performance, even under various deformation/bending conditions. Additionally, important emerging materials suitable for flexible device applications are discussed to inspire investigators to see opportunities for further development in flexible energy storage electronics.