An electrochemical cell assembly (1400) comprising a base plate (308) and a top plate (303) between which a stack of planar cell units (306) and at least one electrical end plate (1402, 1407) are disposed in compression. The electrical end plate (1402, 1407) comprises a two-layer construction in which a first layer (1416, 1419) and a second layer (1417, 1420) formed of different respective materials are permanently connected together to form a single conductive body. The first layer (1416, 1419) of the electrical end plate (1402, 1407) is electrically connected to an external electrical terminal (301, 505) of the cell assembly, and the second layer (1417, 1420) of the electrical end plate (1402, 1407) has an outwardly facing side having a first electrically conductive ceramic layer (1418, 1824) bonded thereto that is in face-to-face abutment with, and in electrical contact with, an adjacent cell unit (306).

A method of monitoring and replacing fuel cells within a fuel cell stack assembly. The method includes measuring one or more operating conditions of a fuel cell within the fuel cell stack assembly. The method includes determining, using a processor, a state of health of the fuel cell based at least in part on the one or more operating conditions. The method includes detaching the fuel cell from an adjacent cell within the fuel cell stack assembly by removing a first electrically-conducing mating matrix associated with a first endplate of the fuel cell from a second electrically-conducing mating matrix associated with a second endplate of the adjacent cell. The method includes attaching a replacement fuel cell by mating a third electrically-conducing mating matrix associated with a third endplate of the replacement fuel cell with a fourth electrically-conducing mating matrix associated with a fourth endplate of the adjacent cell.

A method of monitoring and replacing fuel cells within a fuel cell stack assembly. The method includes measuring one or more operating conditions of a fuel cell within the fuel cell stack assembly. The method includes determining, using a processor, a state of health of the fuel cell based at least in part on the one or more operating conditions. The method includes detaching the fuel cell from an adjacent cell within the fuel cell stack assembly by removing a first electrically-conducing mating matrix associated with a first endplate of the fuel cell from a second electrically-conducing mating matrix associated with a second endplate of the adjacent cell. The method includes attaching a replacement fuel cell by mating a third electrically-conducing mating matrix associated with a third endplate of the replacement fuel cell with a fourth electrically-conducing mating matrix associated with a fourth endplate of the adjacent cell.

Methods for fabricating an interconnect for a fuel cell stack that include providing a protective layer over at least one surface of an interconnect formed by powder pressing pre-alloyed particles containing two or more metal elements and annealing the interconnect and the protective layer at elevated temperature to bond the protective layer to the at least one surface of the interconnect.

Methods for fabricating an interconnect for a fuel cell stack that include providing a protective layer over at least one surface of an interconnect formed by powder pressing pre-alloyed particles containing two or more metal elements and annealing the interconnect and the protective layer at elevated temperature to bond the protective layer to the at least one surface of the interconnect.

A single fuel cell according to the present disclosure includes a power generation section, a power non-generation section which does not include the power generation section, and an oxygen-ion-insulating gas seal film arranged so as to cover the surface of the power non-generation section, and the gas seal film is configured by a structure formed by firing a material containing MTiO.sub.3 (M: alkaline earth metal element) and metal oxide. The structure may include a first structure and a second structure which are different in composition, the first structure may include components derived from MTiO.sub.3 in larger amounts than the second structure, the second structure may include a metal element contained in the metal oxide in a larger amount than the first structure, and the area ratio of the second structure in the structure may be not less than 1% and not more than 50%.

Methods for fabricating an interconnect for a fuel cell stack that include providing a protective layer over at least one surface of an interconnect formed by powder pressing pre-alloyed particles containing two or more metal elements and annealing the interconnect and the protective layer at elevated temperature to bond the protective layer to the at least one surface of the interconnect.

Methods for fabricating an interconnect for a fuel cell stack that include providing a protective layer over at least one surface of an interconnect formed by powder pressing pre-alloyed particles containing two or more metal elements and annealing the interconnect and the protective layer at elevated temperature to bond the protective layer to the at least one surface of the interconnect.

A unit cell for a fuel cell stack including an anode catalyst layer separated by a polymer electrolyte membrane from a cathode catalyst layer, a first cell end plate separated by a first gas diffusion layer from the anode catalyst layer, and a second cell end plate separated by a second gas diffusion layer from the cathode catalyst layer, wherein the first cell end plate, the second cell end plate, or both include a matrix of electrically-conducting protrusions thereof.

A unit cell for a fuel cell stack including an anode catalyst layer separated by a polymer electrolyte membrane from a cathode catalyst layer, a first cell end plate separated by a first gas diffusion layer from the anode catalyst layer, and a second cell end plate separated by a second gas diffusion layer from the cathode catalyst layer, wherein the first cell end plate, the second cell end plate, or both include a matrix of electrically-conducting protrusions thereof.