Redesign high-performance flexible thermoelectrics: From mathematical algorithm to artificial cracks

This work presents a high-performance flexible thermoelectric device (f-TED) by rationally introducing the mathematical algorithm cyclotomic rule into flat-to-flexible inorganic/organic hybrid device design. Artificial cracks and selected substrate-cutting are integrated to realize full flexibility with 0-360 degrees bending angle and low contact resistance. Experimental measurements and numerical simulations as well as contact resistance models indicate and verify the high energy efficiency and power output of the f-TED under various temperature differences and artificial cracks. Noticeably, 19.6 mW/cm(2) power density and similar to 3% power conversion efficiency are achieved at near room temperature (53 K temperature difference) for the bismuth telluride f-TED with a 360 degrees bending angle. These results offer feasibility to use the f-TED for energy generation and thermal management of heat source/sink with different surface curvature, especially in self-powered wearable mechatronics and flexible chip cooling in the Internet of Things.