A miniature thin-film thermoelectric generator (TEG) was developed by Nextreme to convert heat directly into electricity. Suited for waste-heat-conversion applications, the solid-state component delivers power generation densities (>3 W/cm2) in excess of those achieved using bulk materials and is optimized to provide power in a form factor that can be as much as 20 times thinner than bulk material alternatives. Manufactured using semiconductor fabrication techniques, TEG is scalable and cost-effective, and can be utilized in thermal batteries, medical implants, and wireless sensor networks.
“In environments where a lot of heat is available, we have demonstrated power levels of up to 300 mW with devices that are not much bigger than a piece of confetti,” said Seri Lee, PhD, Nextreme’s chief technology officer. “And in low-grade thermal environments, we have demonstrated microwatts of power—enough thermal energy conversion to power remote sensors and other distributed devices.”
The devices generate electricity via the Seebeck effect, where electricity is produced from a temperature differential applied across the device. The temperature difference (∆T) between the hot (Th) and the cold (Tc) sources leads to a difference in the Fermi energy (∆EF) across the thermoelectric material, yielding a potential difference which drives a current. www.nextreme.com