Efficiency Increasing of Thermoelectric Micro Generator Using Carbon Nanotube Interface

摘要

Thermoelectric (TE) devices are an interested family of energy harvesters which could convert the thermal energy into electricity. However, the temperature drops at interface between thermoelectric materials and heat source, heat sink and electrodes reduce efficiency of thermoelectric devices. As a solution, thermal interface materials (TIM) which have high thermal conductance and low thermal interface resistance with adjacent materials are added to the device, m this paper, the organic material is considered as the base material for a TE energy harvester device. Also, carbon nanotube (CNT) is applied as TIM, because of its high one dimentional electrical and thermal conductance. A finite element analysis is carried out in order to investigate the role of thermal contact resistance on heat transfer at TE device. To do this, a thermoelectric leg is simulated with two structure consist of (a) TE material and electrodes in direct contact (b) TE material and electrodes with CNT interface and the results are compared. It is shown that CNT layer reduces heat dissipation at the interface and so the temperature difference at the both sides of polymer is increased, which finally results the enhancement of device output voltage.