Lee, Yun Goo Kim, Junsoo Kang, Min-Su Baek, Seung-Hyub Kim, Seong Keun Lee, Seung-Min Lee, Jaewoo Hyun, Dow-Bin Ju, Byeong-Kwon Moon, Seung Eon Kim, Jin-Sang Kwon, Beomjin 2024-01-20T01:03:46Z 2024-01-20T01:03:46Z 2021-09-05 2017-07 2365-709X https://pubs.kist.re.kr/handle/201004/122586 A critical challenge in using thermoelectric generators (TEGs) for charging the portable or wearable electronics has been their limited outputs, as available temperature differential on human body (Delta T-ext) is typically less than 10 K. Furthermore, the thermal resistance (R-th) at the TEG-air interface often overwhelms R-th of TEG itself, which makes the temperature differential within the TEG merely a small fraction of Delta T-ext. Here, the designs of TEG systems for wearable applications based both on theory and systematic experiments are studied. First, this study fabricates the TEGs having different fill factors (equivalently, varied internal R-th of the TEGs) and finds an optimum fill factor that is determined by both thermal matching condition and the electrical contact resistance. Next, to investigate the effects of heat sink and external air flow, this study combines plate fin heat sinks with the TEGs and evaluates their performance under three different convection conditions: natural convection, and convection with either parallel or impinging flow. Lastly the effect of R-th at the skin-TEG interface is studied. Although the TEG system produces an output power of 126 mu W cm(-2) (Delta T-ext = 7 K) on a smooth heat source (Cu heater), it generates reduced power of 20 mu W cm(-2) (Delta T-ext = 6 K) on wrist (uneven heat source). English WILEY HUMAN-BODY HEAT THERMAL-CONDUCTIVITY ENERGY HARVESTER OPTIMIZATION PERFORMANCE COMPOSITES NITRIDE SYSTEM Design and Experimental Investigation of Thermoelectric Generators for Wearable Applications Article 10.1002/admt.201600292 1 ADVANCED MATERIALS TECHNOLOGIES, v.2, no.7 ADVANCED MATERIALS TECHNOLOGIES 2 7 scie scopus 000405418200015 2-s2.0-85030624019 Materials Science, Multidisciplinary Materials Science Article HUMAN-BODY HEAT THERMAL-CONDUCTIVITY ENERGY HARVESTER OPTIMIZATION PERFORMANCE COMPOSITES NITRIDE SYSTEM heat sinks thermal resistance thermoelectric generators wearable electronics