Electric induced cooling effect in printable thermogalvanic cells

Solid-state cooling technologies are attracting increasing interest as sustainable alternatives to conventional refrigeration systems. Here, we propose and experimentally demonstrate an electrically induced cooling effect in printable thermogalvanic cells (TGCs). The cooling originates from the entropy change associated with reversible electrochemical reactions at the two electrodes. By applying an ultralow voltage below 1 V, a cooling temperature change of approximately 40 mK was achieved. The cooling performance is determined by Seebeck coefficient, internal resistance, and device geometry. Owing to their simple structure, lightweight organic components, and ultralow operating voltage, printable TGC-based coolers may offer opportunities for thermal management in miniaturized, wearable, and flexible electronic systems. This work demonstrates the feasibility of thermogalvanic cooling and provides a foundation for the development of solid-state cooling technologies.