Under the influence of the rapid development of industrialization, energy demand is also increasing. Cars have become a common means of transportation in our daily life, but most of the energy generated by vehicle fuel combustion is wasted and has not been effectively utilized. Using the semiconductor material with Seebeck effect in the thermoelectric power generation technology, the heat energy is converted into electric energy through the transfer of energy, and the phase-change thermoelectric generator related to the recovery of automobile exhaust heat is designed. By means of computational simulation, the output performance is compared with that of the ordinary flat type generator. This technology is not only simple and flexible, but also clean and efficient, and can achieve efficient combination with the current automobile.