Advances in Wearable Thermoelectric Devices: Strategies for Enhancing Wearability and Performance.

Thermoelectric devices (TEDs) offer a compelling solution by enabling solid-state, electrically driven thermal regulation directly on the human body. At the same time, they can function as power sources for small electronic devices by utilizing the temperature difference between the body and the surrounding environment. However, the inherently rigid components used in TEDs limit their ability to conform seamlessly to the curved and dynamic surfaces of the human body. This mismatch often results in interfacial gaps and mechanical delamination during motion, significantly degrading thermal and electrical performance. To overcome these limitations, extensive research efforts have been directed toward structural and material design strategies that enhance the mechanical wearability of TEDs for reliable on-body operation. Here, we review recent advances in wearable TEDs (w-TEDs), highlighting emerging strategies to reconcile mechanical wearability with high device performance. Structural and material innovations that enable mechanical compliance and conformal skin integration are first reviewed, followed by approaches that improve device performance through electrical contact and optimized thermal transport design. We further examine emerging applications in personal thermal management, energy harvesting, and sensing and discuss the remaining challenges and future opportunities for next-generation w-TEDs that simultaneously achieve wearability and high performance.