Enhanced thermoelectric cooling performance with graded thermoelectric materials

Abstract

Abstract An analytic model is presented to estimate the performance of the thermoelectric refrigeration constructed by the functional graded thermoelectric materials with the spatial- and temperature-dependent transport coefficients, such as the Seebeck coefficient, the thermal conductivity and the electrical conductivity along the transport direction. In the case of varied carrier concentration, the temperature-dependent transport coefficients used in our analytic model are calculated by utilizing the Boltzmann transport equations. We find that higher maximum cooling power and larger maximum temperature difference could be achieved in by using graded thermoelectric materials compared to that with homogeneous materials. The optimal distribution of carrier concentration is also discovered to effectively enhance the maximum coefficient of performance.