New insight of thermodynamic cycle in thermoelectric power generation analyses: Literature review and perspectives

Thermoelectric power generation holds promise for the efficiently utilizing low and medium grade energy, and its energy efficiency urgently requires enhancement. However, the primary challenge in improving efficiency lies in the lack of understanding on mechanism. This review is dedicated to elucidating the mechanism through a thermodynamic cycle perspective, including three main aspects: cycle configuration, physical properties, and cycle realization. In cycle configuration section, classical thermodynamic basis for thermoelectric power generation was revisited, and methods on cycle construction was proposed as a perspective. In physical property section, recent advances on three key properties, including Seebeck coefficient, electrical conductivity, and thermal conductivity were reviewed, and how to introduce them into a thermodynamic cycle was discussed. Finally, in cycle realization part, high-entropy optimization under the guidance of thermodynamic cycle was reviewed and discussed. It is found that thermodynamic cycle would provide a powerful tool to understand the energy conversion mechanism for thermoelectric power generation, and guide its further efficiency improvement.