Search this site
English
Contact Us

Flexible thermoelectric generator using bulk legs and liquid metal interconnects for wearable electronics

By Suarez, Francisco; Parekh, Dishit P.; Ladd, Collin; Vashaee, Daryoosh; Dickey, Michael D.;
Published in Applied Energy 2017

Abstract

Abstract Interest in wearable electronics for continuous, long-term health and performance monitoring is rapidly increasing. The reduction in power levels consumed by sensors and electronic circuits accompanied by the advances in energy harvesting methods allows for the realization of self-powered monitoring systems that do not have to rely on batteries. For wearable electronics, thermoelectric generators (TEGs) offer the unique ability to continuously convert body heat into usable energy. For body harvesting, it is preferable to have {TEGs} that are thin, soft and flexible. Unfortunately, the performances of flexible modules reported to date have been far behind those of their rigid counterparts. This is largely due to lower efficiencies of the thermoelectric materials, electrical or thermal parasitic losses and limitations on leg dimensions posed by the synthesis techniques. In this work, we present an entirely new approach and explore the possibility of using standard bulk legs in a flexible package. Bulk thermoelectric legs cut from solid ingots are far superior to thermoelectric materials synthesized using other techniques. A key enabler of the proposed technology is the use of {EGaIn} liquid metal interconnects, which not only provide extremely low interconnect resistance but also stretchability with self-healing, both of which are essential for flexible {TE} modules. The results suggest that this novel approach can finally produce flexible {TEGs} that have the potential to challenge the rigid {TEGs} and provide a pathway for the realization of self-powered wearable electronics.

Read » Back