Abstract
Developing portable power sources with high energy density is of vital importance in the present electronic age. A powerful hybrid micro thermoelectric generator powered by a newly designed ultrahigh capacity miniature combustor is first developed in this work to provide an electric power of over 50 W with a systematic efficiency of 2.92%, filling a research gap – the lack of a concrete method to augment the electric power of combustion-powered micro thermoelectric generators. Segmented thermoelectric modules (PbTe and Bi2Te3) and convectional thermoelectric modules (Bi2Te3) are first combined to suit the inherent uneven hot-end temperature distribution of a combustion-powered micro thermoelectric generator. This method substantially promotes the performance of thermoelectric generator because the total electric power (51.0 W) and electric power per thermoelectric module (12.75 W) are considerably larger than those in previous studies. Temperature distribution, input power between 1229 and 1749 W, equivalent ratio between 0.82 and 1.0, wiring method, cooling intensity, flue gas emissions (CO, NO, and CO2), and various efficiencies are explored in detail to characterize the proposed micro thermoelectric generator. Results show that the present micro thermoelectric generator runs with high systematic efficiency under different input powers and equivalent ratios and produces lower pollutant emissions (CO and NO) compared with those in previous studies. The combination of an ultrahigh capacity miniature combustor with volumetric heat load of 78.9 WM/m3, an all-in-one designed combustor-collector-spreader, and hybrid thermoelectric modules (segmented and convectional thermoelectric modules) is the essential innovation to reach the abovementioned improved performance. Detailed discussions concerning various efficiencies (systematic, combustion, heat collection, and TE efficiencies), power density, energy density and pressure drop of hybrid thermoelectric generator are conducted in this work. The present work presents a concrete method to develop a high capacity combustion-powered micro thermoelectric generator and provides in-depth insights into the utilization of inherent uneven hot-end temperature distribution of a combustion-powered micro thermoelectric generator.
NSTL
Elsevier