Abstract
Ionic thermoelectric energy conversion uses ions as carriers to convert heat into electricity. The high temperature-induced voltage of several millivolts per degree Kelvin has attracted more attention to the application of self-powered sensors in IoTs. In this perspective, the thermogalvanic and thermodiffusion effects are illustrated, together with the research advances on ionic thermoelectric gels. However, the status in recent 3 years is high temperature-induced voltage but low output power. The authors propose that the synergy of two effects and electrode design are believed to be effective ways to improve ionic thermoelectric properties.