Multiphysics simulation of thermoelectric systems for comparison with experimental device performance

The efficiency of thermoelectric devices is determined not only by the quality of the thermoelectric material but also by the geometrical design of the legs and the properties and design of the contacts with the corresponding soldering process. These influences on the performance of a thermoelectric generator are studied by multiphysics finite element modeling. The simulated data are compared with experimental results for modules manufactured from Bi2Te3 compounds with ZT values > 0.8. A decrease of the ZT value for the module by a factor of about four can be traced back to the high contact resistance. The thermal losses at the contact interfaces are negligible for these devices.