A liquid thermoelectric converter composed of acetone–water mixed solution with reduced solution resistance†

The maximum power (W_max) per unit area of the electrode of a liquid thermoelectric converter (LTE) is determined by the electrochemical Seebeck coefficient α and device resistance R as W_max = , where ΔT and s are the temperature difference between electrodes and electrode area, respectively. In an organic LTE containing Fe²⁺/Fe³⁺, α is much higher than that of the corresponding aqueous LTE even though R is higher. Here, we searched for pure and/or mixed organic solution with lower solution resistance R_s using viscosity η as a clue. We demonstrated that W_max of an LTE (electrode distance d is 10 mm) composed of acetone–H₂O electrolyte is 31% higher than W_max of the corresponding aqueous LTE.