TCs Connectivities Effect Investigation in the LTCC-based Thermoelectric Generator for Automotive Waste Heat Recovery

This paper presents the design optimization of thermoelectric generators (TEGs) based on low temperature co-fired ceramic (LTCC) technology. Three designs, containing 45 Ag/Ni thermocouples each, were studied: two conventional designs (π-type and Y-type TEGs) and one newly proposed design. The optimization was carried out to improve the temperature difference along thermocouple (TC) arms by increasing thermal resistance of the structure and by increasing the temperature difference path with maintaining the same TC dimensions. For thermoelectric modules (TEMs) with 60 generators, the optimized TEG produces maximum electrical power of 1.7 W at $\Delta \mathrm{T}_{\mathrm{T}\mathrm{E}\mathrm{G}}=230\ {^{\circ}\mathrm{C}}$ while the $\pi-$ and Y-type thermoelectric generators produces respectively maximum output power of 0.022 W and 1 W.