During heating up, a pre-stacking pressure which is a bit lower than desired stacking pressure was applied on the cell in order to minimize internal delamination due to thermal expansion. The La2Ni0.75Co0.25O4.08/La0.9Ba0.1F2.9/Pb-PbF2 cell was cycled at 170 °C under ~ 450 MPa with a current density of 19.2 µA/cm 2 and 9.6 µA/cm 2 for charging and discharging respectively.