Harvesting heat from the human body is a promising approach to realizing self-powered wearables that run continuously without the need to charge or replace the batteries. Thermoelectric generators placed on the body can convert the small temperature difference between the body and the ambient to electricity.
To power sophisticated wearables that can wirelessly transfer information from many sensors, the heat harvesting area on the body may have to be several inches square or larger, which is difficult to accomplish with rigid thermoelectric modules.
ASSIST has developed a flexible thermoelectric generator technology by encasing the semiconductor elements in a silicone elastomer. In these devices, low-resistivity, stretchable, self-healing liquid metal interconnects are used to connect the elements electrically in series. The flexible package incorporates novel elastomers that are developed to have lower (or higher) thermal conductivities to optimize the thermal management of the flexible package. ASSIST flexible thermoelectric generators provide the highest power levels reported to date.