Polymers for flexible energy storage devices

Flexible energy storage devices have received much attention owing to their promising applications in rising wearable electronics. By virtue of their high designability, light weight, low cost, high stability, and mechanical flexibility, polymer materials have been widely used for realizing high electrochemical performance and excellent flexibility of energy storage devices. In this review, flexible energy storage devices including supercapacitors and batteries are firstly introduced briefly. Then the design requirements and specific applications of polymer materials as electrodes, electrolytes, separators, and packaging layers of flexible energy storage devices are systematically discussed with an emphasis on the material design and device performance. The remaining challenges and future directions are finally summarized to guide future studies on the development of polymer materials for flexible energy storage devices.