Exploring TEG parameters for optimal body heat harvesting in wearable devices

Abstract

Thermoelectric generators harness human body heat to power wearable electronic devices and are crucial for developing self-sustaining wearable systems for health and environmental monitoring. This research focuses on optimizing the power output of body heat-driven wearable thermoelectric generators, while ensuring user comfort. It emphasizes minimizing heat loss, maintaining a significant temperature differential across the thermoelectric material, and designing compact generators. Investigations explored temperature-regulated hot surfaces at various body sites including the wrist, upper arm, and chest. Power levels were recorded during activities such as running and walking. Findings indicate that power generation was most effective at the upper arm, peaking at 71.2 millivolts with a thermoelectric generator equipped with a heat sink silver spreader and silicon insulator during summer conditions. The study also evaluated the feasibility of using upper arm thermoelectric generators to power wearable electrocardiogram sensors. In comparison, while thermoelectric generators at the wrist benefited from airflow in winter, achieving up to 29.3 millivolts, those at the chest showed superior power output. This research underscores the potential of strategically placed thermoelectric generators in enhancing the functionality of wearable technologies.