Reciprocity Relation in Thermoelectric Composites: Optimizing Materials for Energy Efficiency and Thermal Management

Effective kinetic properties of two-phase heterogeneous media with thermoelectric properties have been considered. These properties manifest themselves when an electric current and a heat flow coexist in the medium. It is shown that in some cases, it is possible to generalize the reciprocity relations obtained in the absence of thermoelectric phenomena and find invariants (combinations of effective thermoelectric coefficients) with respect to changes in the phase concentration in the two-dimensional case. For the three-dimensional case, using the moving percolation threshold approach in the mean-field theory, it is shown that similar reciprocity relations (invariants) can be approximately satisfied when the percolation threshold is shifted.