Abstract

Continuous advancements in information technologies, electronic devices, and biomedical applications have attracted great interest in the development of flexible batteries to provide the necessary energy to these systems. Due to their high energy, high power density, and long cycle life, lithium-ion batteries (LIB) are the best candidate as an energy storage device to meet the requirements of these next-generation technologies. Traditional LIBs are still not sufficient for flexibility since the cell components are not compatible with the necessary mechanical deformations, such as bending, stretching, twisting, folding, and distorting. Flexible LIBs suffer from high impedance, capacity fade, electrolyte leakage, and cycle life loss during their operation. Therefore, the development of novel unit components with high electrochemical performance, high durability, and flexibility are vital for the incorporation of these energy storage devices into wearable and portable consumer electronics. This chapter reviews in detail the state-of-the-art recent investigations on the design, production, and application of electrolyte components and electroactive materials, with a special focus on carbon-based materials such as carbon nanotubes, graphene, carbon nanofibers, carbon cloth and paper, and MXenes, the emerging 2D-materials for FLIBs. In addition, lightweight, binderless, free-standing cell structure and fabrication techniques are further mentioned within the chapter.