Fuel cell system

A fuel cell system comprising:

• a fuel cell stack including a plurality of power generation cells that are stacked together;
• a stack case containing the fuel cell stack;
• and
• an electrical equipment unit provided in the stack case,
• wherein the stack case comprises:
• a case body configured to cover the fuel cell stack from a direction perpendicular to a direction in which the plurality of power generation cells are stacked together;
• a first end cover tightened to the case body by a plurality of first bolts extending in the stacking direction in a manner to cover a first opening at one end of the case body;
• and
• a second end cover tightened to the case body by a plurality of second bolts extending in the stacking direction in a manner to cover a second opening at another end of the case body, and
• wherein a plurality of first screw holes are formed in one end surface of the case body, and the plurality of first bolts are configured to be screwed into the first screw holes in a state where the plurality of first bolts are inserted into a plurality of first insertion holes formed in the first end cover;
• a plurality of second screw holes are formed in another end surface of the case body, and the plurality of second bolts are screwed into the plurality of second screw holes in a state where the plurality of second bolts are inserted into a plurality of second insertion holes formed in the second end cover;
• a recess is formed in an outer surface of the case body in a manner that the recess is interposed in the stacking direction between at least one of the plurality of first screw holes and at least one of the second screw holes and that the electrical equipment unit is disposed in the recess;
• a first screw hole among the plurality of first screw holes aligned with the recess in the stacking direction penetrates through the case body from one end surface to a side surface of the recess;
• a ventilation portion provided for the second end cover in a manner to cover the plurality of second bolts from outside, and configured to discharge the fuel gas leaked from the fuel cell stack to outside of the stack case;
• a second screw hole among the plurality of second screw holes aligned with the recess in the stacking direction is closed on one side of the recess closer to the other end of the case body;
• and
• an outer seal member configured to seal a position between the case body and the second end cover in an air-tight manner is provided between the plurality of second screw holes and an outer surface of the case body and surrounds all of the plurality of second screw holes, and
• wherein an outer groove in which the outer seal member is provided outside the plurality of second screw holes in the another end surface of the case body or outside the plurality of second screw holes in an inner surface of the second end cover, and
• an internal space of the case body and an internal space of the ventilation portion are in communication with each other through the second insertion holes and a space between the another end surface of the case body and the inner surface of the second end cover, the space being positioned inwardly of the plurality of second screw holes and the plurality of second insertion holes.