The separators 600 included in the cell stack 122 may correspond to some of all of the separators included in the fuel cell.

For example, all of the separators included in the fuel cell may be grouped into a plurality of unit groups, and each unit group, as illustrated, may include a plurality of separators 600. For example, the unit group shown in FIGS. 2 to 4 may include ten separators 600. In this case, the cell-monitoring connector may be detachably mounted on each of the unit groups of the fuel cell.

The separators 600, in each of which the receiving recess H1 including first, second and third sides H1S1, H1S2 and H1B is formed, may be disposed so as to overlap each other in the first direction. The receiving recesses H1 formed in the separators 600 define a receiving space into which the cell-monitoring connector 300 is fitted. That is, the receiving recesses H1 disposed in the first direction form a receiving space.

The gaskets may be disposed on the opposite surfaces (e.g. 600S1 and 600S2 shown in FIG. 7B, which will be described later) of each of the separators 600 so as to be located around the receiving recess H1, and may have a hook shape. Here, the hook shape is a shape to which latching protrusions 314M and 316M shown in FIG. 6 (which will be described later) may be latched. As shown in FIG. 5, the hook shape may be an “L” shape, but the embodiment is not limited thereto.