Thermoelectric module and generator for gasoline engine vehicles

An advanced type thermoelectric module based on SiGe has been developed to apply it to gasoline engine vehicles. The size of the module is 20 mm square and 9.2 mm in height. The module consists of 8 couples of p- and n-type Si-Ge elements. The elements are electrically connected in series using Mo electrodes by brazing method. The maximum electric power of the module is approximately 1.2 W, at the temperature difference 563 K between hot and cold sides of the module. A thermoelectric generator has been made using 72 units of the present module. The modules are arranged between an exhaust pipe with a rectangle cross section and a water jacket around the exhaust pipe. The volume of the generator is 440×180×170 mm³. Generated electric power of the present generator was 35.6 W, when the exhaust gas was introduced into the generator under the condition corresponding to the 60 km/hr hill climb mode of 3000 cc gasoline engine vehicle. The heat exchange efficiency of the generator was estimated at 11% of the primary exhaust gas energy flux. The generated power was 0.9% of the heat flux through the generator