Characteristics of a Pin–Fin Structure Thermoelectric Uni-Leg Device Using a Commercial n-Type Mg2Si Source

Abstract

Mg2Si thermoelectric (TE) elements and modules were fabricated using a commercial polycrystalline Mg2Si source. A monobloc plasma-activated sintering technique was used to fabricate the TE elements and Ni electrodes. The TE modules were composed of n-type Mg2Si, using pin–fin structure elements, in order to achieve simple assembly and to realize stable operation at a temperature of ~800 K. The dimensions of each pin–fin element were 4.2 mm × 4.2 mm × 9.8 mm, and the TE module comprised nine pin–fin elements connected in series. The output characteristics of the pin–fin elements and the TE module were evaluated at temperature differences, ΔT, ranging from 100 K to 500 K. The observed values of open-circuit voltage (V OC) and output power (P) of a single pin–fin element were 98.7 mV and 50.9 mW, respectively, at the maximum ΔT of 500 K. The maximum V OC and P values for the TE module were 588 mV and 174.3 mW, respectively, at ΔT = 500 K.