Characteristics of Fe-air battery using Y2O3-stabilized-ZrO2 electrolyte with Ni–Fe electrode and Ba0.6La0.4CoO3-δ electrode operated at intermediate temperature

•The charge-discharge operation of 10 cycles was achieved by NiFe-91 and BLC electrode at 600 °C.•The energy density of 600 mWh/g-Fe was maintained during 8 cycles.•The low stability of NiFe-91 electrode during the operation was found.

The charge-discharge operation of a Fe-air battery using YSZ electrolyte at lower temperature was investigated using the NiFe-91 (Ni:Fe = 90:10 wt%) bimetal electrode as the fuel electrode and the Ba0.6La0.4CoO3-δ (BLC) oxide electrode as the air electrode in this work. It was found that the total resistance of the cell using the NiFe-91 and BLC electrode was about 100 times smaller than that of the cell using the conventional Pt electrode, owing to its significantly small electrode resistance. It was also found that the 10 cycle charge-discharges were achieved at 600 °C by using these electrodes, and the capacity of about 700 mAh/g-Fe and energy density of 600 mWh/g-Fe were also retained during 8 cycles. These results showed a significant potential; the low temperature operation of the battery using YSZ electrolyte is sufficiently possible by choosing an appropriate electrode. However, the low stability of the NiFe-91 electrode, which is due to the agglomeration, was also found in this work.