Determination of the Characteristics of Thermoelectrics with High and Ultra-high Values of the Seebeck Coefficient

Abstract

The most important problems facing society today is energy supply of humanity. One of the clear examples of direct energy conversion isthermoelectric effect, which consists in obtaining electric potential using a temperature difference.The obtaining and study of materials with high values of the Seebeck coefficient is one of the main factors for the efficient operation of thermoelectric devices. This article analyzes works in which high and ultra-high values of the Seebeck coefficient were obtained. The new formula is used to calculate resistivity, carrier concentration or Seebeck coefficient in cases where one of these parameters is not measured or calculated. Important thermoelectric parameters of materials are electronic quality- and scaled power factors. The scaled power factor (SPF) of a number of thermoelectric materials is analyzed. The graph of its dependence on the Seebeck coefficient agrees well and complements the graph known from the literature for a large number (more than 3500) of samples towards higher values of the Seebeck coefficient. Based on the values of SPF and resistivity (or conductivity), the electronic quality factor of some materials is calculated. Its temperature dependence provides information about the mechanism of charge carrier scattering. The universal electrical conductivity is calculated. Its temperature dependence and the dependence of the Seebeck coefficient on it confirm that the electronic quality factor scales the thermoelectric parameters of materials.