Effect of Temperature Difference on the Power Output of CaMnO₃ and Ca₃Co₄O₉ Thermoelectric Generators

The power output of CaMnO₃ and Ca₃Co₄O₉ thermoelectric generators(TEG) was measured from room temperature to 600℃, their maximum power was directly proportional to the square of temperature difference across the TEGs.The proportionality constant was also proportional to the ratio between the square of weighted mean for Seebeck coefficient(with the temperature gradient as weighting function) and the average electrical resistivity.The ratio combined the performance parameters of thermoelectric materials such as Seebeck coefficient, electrical conductivity and thermal conductivity, can be measured approximately and easily, and can be used to characterize the performances of TEGs.