Fuel cell

A fuel cell comprising:

• one or more membrane-electrode assemblies each formed by joining a polymer electrolyte membrane and electrodes;
• two or more separators disposed to sandwich the membrane-electrode assembly;
• a pair of first quadrangular end plate and second quadrangular end plate, each of which includes an electrode facing region facing the electrode and an annular outer edge region surrounding the electrode facing region and having openings, and which are disposed to sandwich a stack structure including said one or more membrane-electrode assemblies and said two or more separators;
• a first current collector disposed between one end of the stack structure and an inner surface of said first end plate;
• a second current collector disposed between the other end of the stack structure and an inner surface of said second end plate;
• a first fastening rod, a second fastening rod, a third fastening rod and a fourth fastening rod which extend in a stack direction of the stack structure so as to penetrate through the openings of said first end plate and the openings of said second end plate;
• fastening portions which are disposed at both ends of said first, second, third and fourth fastening rods and are able to adjust fastening forces applied by said first, second, third and fourth fastening rods to the stack structure sandwiched between said first and second end plates;
• a plurality of first elastic members disposed between the inner surface of said first end plate and said first current collector;
• and
• a plurality of second elastic members disposed between the inner surface of said second end plate and said second current collector, wherein:
• when an outer surface of said first end plate is viewed in the stack direction, vertices of said first end plate corresponding to four corners of the outer surface of said first end plate are a first vertex, a second vertex, a third vertex and a fourth vertex in a clockwise direction, a side of said first end plate connecting the first vertex and the second vertex is a first side, a side of said first end plate connecting the second vertex and the third vertex is a second side, a side of said first end plate connecting the third vertex and the fourth vertex is a third side, a side of said first end plate connecting the fourth vertex and the first vertex is a fourth side, a straight line passing through an intermediate point of the first side and an intermediate point of the third side is a first axis, and a straight line passing through an intermediate point of the second side and an intermediate point of the fourth side is a second axis,
• said first fastening rod is disposed on the first axis extending within the outer edge region located between the first side and the electrode facing region;
• said second fastening rod is disposed on the second axis extending within the outer edge region located between the second side and the electrode facing region;
• said third fastening rod is disposed on the first axis extending within the outer edge region located between the third side and the electrode facing region;
• said fourth fastening rod is disposed on the second axis extending within the outer edge region located between the fourth side and the electrode facing region;
• one or more first elastic members out of said plurality of first elastic members are disposed within the electrode facing region of said first end plate and on a first straight line passing through said first and second fastening rods;
• one or more first elastic members out of said plurality of first elastic members are disposed within the electrode facing region of said first end plate and on a second straight line passing through said second and third fastening rods;
• one or more first elastic members out of said plurality of first elastic members are disposed within the electrode facing region of said first end plate and on a third straight line passing through said third and fourth fastening rods;
• and
• one or more first elastic members out of said plurality of first elastic members are disposed within the electrode facing region of said first end plate and on a fourth straight line passing through said fourth and first fastening rods.