Ni-Fe-Ce(Mn,Fe)O sub(2) cermet anode for rechargeable Fe-Air battery using LaGaO sub(3) oxide ion conductor as electrolyte

There is a strong demand for the development of a large capacity rechargeable battery in various fields. Recently, we proposed the combination of solid oxide fuel cell technology with Fe-air battery concepts using H sub(2)/H sub(2)O as a redox mediator and a LaGaO sub(3)-based oxide as an electrolyte. Because large internal resistance and large degradation during charge and discharge cycles were observed on the anode, there is a strong demand for improvements in discharge potential and cycle stability. This study investigates the use of a cermet anode consisting of a Ni-Fe alloy combined with an oxide ion conductor. It was observed that by using a cermet anode of Ni-Fe combined with Ce sub(0.6)Mn sub(0.3)Fe sub(0.1)O sub(2) (CMF), the observed capacity of the cell was improved to 1163 mAh g super(-1) Fe super(-1) at 10 mA cm super(-2) and 873 K. This is about 97% of the theoretical capacity by assuming the formation of Fe sub(3)O sub(4) (1200 mAh g super(-1) Fe super(-1)). Cycle stability of the cell was also considerably improved with the use of a Ni-Fe-CMF anode compared to a Ni-Fe anode because of the suppressed aggregation provided by the mixing of Ni with CMF.