Conveyor mode enabling continuous ionic thermoelectric conversion

The huge thermopower observed in the thermodiffusion mechanism of ionic thermoelectric (i-TE) materials has led researchers to conceive of the upgrading of thermoelectric technology. However, the intermittent power generation in the capacitor mode has been a major hindrance to achieving optimal performance. This work proposes a conveyor mode for continuous i-TE conversion in mixed ion-electron-conducting i-TE material with an ionic circuit. In this conveyor mode, ion-electronic friction serves as the link between ions and electrons, enabling the thermally diffused ions to convey electrons to power the load, and persistent ionic transport, owing to the ionic circuit, ensures continuous power generation. Experiments demonstrate continuous power generation and significant improvements of power density in the conveyor mode. Theoretical analysis shows that the conveyor mode is competitive to not only the capacitor mode but also a general electronic thermoelectric conversion. Our study points out a direction for the development of i-TE technology.