Green Supercapacitors in Portable and Wearable Electronics

Due to the miniaturization of electronic devices, considerable effort has been applied to progress high-performance, wearable, and portable energy storage devices for driving integrated active devices like electrical sensors, flexible displays, and health monitoring systems. Recently, progress in flexible and wearable supercapacitors has increased owing to their ease of fabrication, low cost, flexible integration into textiles, stable cycle life, quick charging–discharging, high efficiency, and capability to provide superb energy and power density. In particular, wearable, and portable electrochemical supercapacitors having their unique advantages involving flexibility, shape-conformability, and low weight, are attracting ever-increasing attention to meet the requirement for wearable and portable electronic devices in modern energy storage markets. Using green supercapacitor technology, we can design green energy storage devices in wearable/portable electronics to tackle the global energy problem to build a sustainable and green society. In this chapter, we will summarize the recent advances of wearable and portable supercapacitor devices by discussing their performance and adopted strategies to improve the electrochemical performance. Lastly, associated challenges, and future outlooks in optimizing and developing green supercapacitor-based multifunctional wearable and portable energy storage devices for their practical applications regarding flexibility and sustainability are addressed.