Abstract: An electrochemical cell including a solid electrolyte layer containing ZrO2 containing a first rare earth element; a cathode disposed on one side of the solid electrolyte layer; and an anode disposed on the other side of the solid electrolyte layer. The anode contains CeO2 containing a second rare earth element and Ni or an Ni-containing alloy. The electrochemical cell further includes an intermediate layer disposed between the solid electrolyte layer and the anode. The intermediate layer contains a solid solution containing Zr, Ce, the first rare earth element, and the second rare earth element. Also disclosed is an electrochemical stack including a plurality of the electrochemical cells, where the electrochemical stack is a solid oxide fuel cell stack or a solid oxide electrolysis cell stack.