Fuel cell separator assembly with diffusion layer, manufacturing method therefor, fuel cell unit, and fuel cell stack

A method for fabricating a separator assembly, comprising the steps of:

• providing a diffusion layer including a porous metal body for diffusing and supplying fuel or oxidizer to an electrode of a fuel cell stack, and a separator including a metal plate;
• disposing the separator adjacent to the diffusion layer;
• and
• emitting a laser beam in the direction from the separator to the diffusion layer so as to laser-weld the diffusion layer with the separator.

A method for fabricating a separator assembly, comprising the steps of:

• providing a diffusion layer including a porous metal body for diffusing and supplying fuel or oxidizer to an electrode of a fuel cell stack, and a separator including a metal plate;
• disposing the separator adjacent to the diffusion layer;
• and
• emitting a laser beam in the direction from the diffusion layer to the separator so as to form flow passage partitions for defining a flow passage for the fuel or oxidizer in the diffusion layer.

A fuel cell unit comprising:

• a first electrode which is disposed in a first side of an electrolyte, and to which fuel is supplied;
• a second electrode which is disposed in a second side of the electrolyte, and to which oxidizer is supplied;
• diffusion layers including porous metal bodies which are respectively disposed adjacent to the first electrode and the second electrode, and which are provided for diffusing and supplying the fuel or the oxidizer to the first and second electrodes, respectively;
• and
• separators including metal plates which are respectively disposed adjacent to the diffusion layers,
• wherein the diffusion layer and the separator, which are disposed adjacent to each other, are welded together by laser-welding.