Soft and Highly Conductive Structured Materials for Wearable Thermoelectric Devices

The incorporation of thermoelectrics in wearable technology has attracted considerable attention with the potential of energy harvesting for powering electronic devices and providing sustainable thermal comfort for human body. Local thermoelectric generating/cooling can be achieved by conventional bismuth telluride p- and n-type thermoelectric pellets, but there is a need for uniform distribution of electric current and heat over large areas with soft and stretchable conductors in wearables. However, current technologies have limitations in terms of low electrical and thermal conductivity, and softness which result in impractical devices. Here, we develop a novel class of soft structured materials that combines the unparalleled performance of conventional metals with the unique electromechanical properties of emerging stretchable composites. By employing a new structural design, the high performance stretchable conductor circumvents the weakness of conventional kirigami materials and serpentine design, and demonstrates superior conductivity with low sheet resistance, high stretchability, and low effective Young’s modulus. The conductors allow for seamless integration of thermoelectric coolers and heat sinks into clothing to facilitate wearable technology for efficient large-scale applications.