Study of Fiber-Based Wearable Energy Systems

Area of Science:

• Materials Science
• Mechanics
• Device Physics

Background:

• Fiber-based electronic and photonic devices offer human-friendly features for human-environment-machine interfaces.
• Wearable devices require reliable, undisrupted power, ideally from harvested ambient or body energy.
• Advancements in flexible materials and energy conversion devices necessitate fundamental studies of underlying physical phenomena.

Purpose of the Study:

• To review recent progress in fiber-based energy harvesting devices.
• To establish and verify theoretical models for piezoelectric, triboelectric, and hybrid generators.
• To guide the exploration, development, and engineering design of wearable energy harvesting systems.

Main Methods:

• Development of theoretical models based on materials science, mechanics, and device physics.
• Experimental verification of established theoretical models.
• Analysis of electric breakdown phenomena to determine theoretical upper limits for triboelectric nanogenerators.
• Setup of an experimental platform for triboelectric charge measurement of deformable materials.
• Exploration of new flexible thermoelectric materials and fabrication processes.

Main Results:

• New theoretical models for fiber-based piezoelectric, triboelectric, and hybrid generators were established and experimentally verified.
• Fiber-based triboelectric generators showed excellent results without adjustable parameters.
• No synergistic effect was detected in hybrid piezoelectric-triboelectric generators.
• Theoretical upper limits for charge density and output power of contact-mode fiber-based triboelectric nanogenerators were identified.
• Improved performance of energy harvesting devices based on findings and an extended triboelectric series.
• Development of high-performance, flexible thermoelectric materials for fiber-based generators using cost-effective methods.

Conclusions:

• Verified models provide predictive capabilities for device output based on material properties, device structure, and operating conditions.
• Theoretical upper limits offer guidance for engineering design and future exploration of triboelectric nanogenerators.
• New flexible thermoelectric materials and fabrication methods enable potential applications in powering wearable systems and waste heat recovery.