Mechanical properties of thermoelectric generators

To satisfy the requirements of practical applications, thermoelectric generators should be highly efficient and mechanically robust. Recently, progress in designing high-performance thermoelectric generators has been made. However, the mechanical properties of thermoelectric generators are still unsatisfactory. In this review, studies on the mechanical properties of thermoelectric generators are summarized. The mechanical properties of bulk thermoelectric generators will be first discussed. In this section, the mechanical properties of thermoelectric materials and the strategies for improving their mechanical properties are emphasized. Since the device's failure usually occurs at the interface between the thermoelectric materials and electrode, the joint strength of electrodes and thermoelectric materials will be overviewed. After that, the mechanical properties of the inorganic thin-film thermoelectric devices will be discussed. Since the figure of merit for the flexibility of thermoelectric materials depends on the film thickness, elastic modulus, and yield strength, the synthesis methods of thin-film thermoelectric materials will be reviewed. Finally, this review will be concluded with a discussion on flexible organic thermoelectric devices and flexible devices using bulk legs.