P. Ingale, M. Sakthivel, J.-F. Drillet
In this work, a novel secondary Zn/air battery using protic Diethylmethylammonium trifluoro-methanesulfonate (DEATfO) ionic liquid as electrolyte and Pt/C as gas diffusion electrode was developed. The bi-functional activity of Pt/C GDE and the quasi reversibility of Zn electro-deposition/stripping in DEMATfO were demonstrated by using cyclic voltammetry method under half-cell conditions. The effect of temperature, humidity and cycling on cell performance was investigated under full-cell configuration with 0.01 M ZnTfO in DEMATfO. Interestingly, in dry air and ambient air, Zn/air cell was quite stable for about 700 h. The average cell voltage of Zn || DEMATfO + 0.01 M ZnTfO || Pt/C system was 1.2 and 1.8 V during discharging and charging step for 2 h each at 50 μA cm−2, respectively. First experiments in ambient air were also very promising. However, maximal cell power density was relatively low (45 μW cm-2). This can be explained by low contact angle of the IL on GDE substrate that presumably hindered triple-phase boundary formation.
Dr.-Ing. Jean-François Drillet
Tel.: 069 / 75 64-476