Determination of the Thermoelectric Figure of Merit Through the Maximum Temperature Depression Using the Peltier Cooling Effect

In the last 30 years of thermoelectric research, many scientists determined thermoelectric efficiency of a material using many different methods. However, by using an alternative physical phenomenon (Peltier cooling), the figure of merit can be determined with minimal energy loss and error. The use of Peltier cooling is a novel method, and this research used a developed segmented model to determine the figure of merit using a Bismuth telluride-Constantan thermocouple to oversee a temperature gradient directly proportional to the figure of merit. In this research, an established mathematical calculation was conducted to have an expected value for a maximum temperature difference. From there, the team was able to use a newly developed segmented model containing elements of both the semiconductor and metal; current was run through the model, and a temperature gradient was observed as a result of the Peltier cooling effect. Matlab code was used to generate a system of equations designed to numerically label the maximum temperature difference. In comparison to the expected maximum 12 degrees K, a value of 10.7 degrees K was obtained from the segmented value. Although slightly lower, it was expected not to be exactly 12 due to radiation loss. Future work in this research includes redoing the calculations taking into consideration radiation loss within the model. Research in using an alternative method will help manufacturing in fields such as engineering or refrigeration design. This method, once refined, provides a much more efficient way of determining the figure of merit in thermoelectric materials