NOVELTY - The fuel cell system comprises electrochemical cells (12), an interconnect (16), and a cathode conductive layer (30). Each electrochemical cell includes an anode (40), a cathode spaced apart from the anode, and an electrolyte disposed between the anode and the cathode. The interconnect electrically couples a pair of electrically adjacent electrochemical cells, and couples the anode to the cathode. The cathode conductive layer is electrically coupled to the interconnect. The interconnect is present in contact with the cathode conductive layer and in contact with the electrolyte.    USE - Used as a fuel cell system.    ADVANTAGE - The efficient fuel cell system exhibits improved performance and compact size.    DETAILED DESCRIPTION - The fuel cell system comprises electrochemical cells (12), an interconnect (16), and a cathode conductive layer (30). Each electrochemical cell includes an anode (40), a cathode spaced apart from the anode, and an electrolyte disposed between the anode and the cathode. The interconnect electrically couples a pair of electrically adjacent electrochemical cells, and couples the anode to the cathode. The cathode conductive layer is electrically coupled to the interconnect. The interconnect is present in contact with the cathode conductive layer and in contact with the electrolyte, and is formed from a cermet compound having a non-ionic conducting ceramic phase. The cermet compound metal phase is a precious metal or a precious metal alloy, and includes an ionic conducting phase. The interconnect includes a portion embedded within the electrolyte. An amount of non-ionic conducting phase in the cermet compound is determined to render balance of the ionic conducting phase to below a percolation threshold. The cathode conductive layer is present in contact with the electrolyte. The interconnect is configured to conduct free electrons between the anode and the cathode, and adjoins the cathode conductive layer and the electrolyte. The ceramic phase of the cermet compound further includes a garnet having A-site and/or B-site substitutions.    DESCRIPTION OF DRAWING(S) - The diagram shows a schematic cross-sectional view of a fuel cell system.    Electrochemical cell (12)    Interconnect (16)    Cathode conductive layer (30)    Anode (40)    Anode conductor films. (48)