Recent advancements in supercapacitor-integrated self-powered sensors

The rapid development of flexible electronics has transformed multiple fields, including wearable and implantable healthcare devices, smart sensors, flexible displays, brain-machine interfaces, aerospace, and robotics. Wearable sensors, such as strain, temperature, humidity, pressure, gas, and biosensors, offer lightweight, flexible, and biocompatible solutions for real-time monitoring. However, their dependence on external power sources limits their practical applicability, long-term operation, and poses challenges for miniaturization and integration. Self-powered sensing systems, particularly those integrating energy storage devices such as supercapacitors, provide a reliable and efficient alternative. Supercapacitors offer high power density, rapid charge/discharge capability, long cycling stability, environmental safety, and biocompatibility, making them ideal for autonomous sensing applications. Recent research emphasizes not only improving electrochemical performance but also integrating supercapacitors with smart sensors for autonomous operation. This review article systematically examines supercapacitor-integrated self-powered sensing systems, including design configurations, materials, and development timelines, and their integration with diverse wearable health monitoring sensors, including strain, temperature, pressure, humidity, gas sensors, and biosensors. Further, key challenges in self-powered sensing systems, including energy management, material and structural compatibility, reliability, flexibility, and scalability, have been discussed in detail. Finally, future perspectives and strategies for overcoming current limitations for next-generation, efficient, and intelligent self-powered sensors are highlighted. • This review explores self-powered sensing systems, including flexible supercapacitor integrated with sensors. • It offers an in-depth analysis of their scientific findings and performance reported in the literature. • It discusses various integration strategies for supercapacitors powering different kinds of flexible and wearable sensors. • It also addresses current challenges in supercapacitor-integrated sensors and mitigation strategies for future work.