Stretchable ionic conductive gels for wearable human-activity detection

Stretchable ionic conductive gels have attracted much attention due to their unique properties, such as high ionic conductivity, tunable flexibility and stretchability. Sensors made from these stretchable ionic conductive gels, attached to the skin surface as ionic conductors, could be used to monitor human activity. Recently, much investment has been made in the development of stretchable ionic conductive gels to meet the needs of flexible sensors and significant progress has been made. The latest advances in stretchable ionic conductive gels are presented, including gel types, properties and stretchable sensors integrated with ionic conductive gels. This paper first reviews the latest successful examples of stretchable ionic conductive gels and their preparation methods and challenges. In the following section, the comprehensive properties of ionic conductive gels are described in detail. Then, some of the latest research results on wearable strain sensors integrated into ionic conductive gels are discussed. Finally, further research directions and challenges for the development of wearable strain sensors integrated into multifunctional ionic conductive gels for human motion monitoring are proposed.