Power Generation Using Oxide Thermoelectric Modules

Different versions of thermoelectric unicouples composed of p-type Ca3Co4O9 (Co-349) and n-type LaNiO3 (Ni-113) or CaMnO3 (Mn-113) bulk materials were prepared. In the unicouples p- and n-type legs were connected with Ag electrodes using Ag paste including various oxide powders with various ratios. For the Co-349/Ni-113 unicouples, maximum output power (Pmax) reaches 177mW at a hot side temperature (TH) of 1073K and a temperature differential (ΔT) between TH and cold side temperature of 500K at 6wt% of Co-349 powder. On the other hand, the lowest internal resistance (RI) is observed in a Co-349/Mn-113 unicouple prepared using Ag paste including 3wt% of Mn-113 powder. Thermoelectric modules consisting of 8 pairs of oxide legs were fabricated using the same method with the unicouples. The open circuit voltage (VO) and Pmax increase with increasing TH and reach 0.392 V and 0.314 W, and 0.911 V and 0.233 W at a TH of 1273 K in air for the Co-349/Ni-113 and Co-349/Mn-113 modules, respectively.