FUEL CELL STACK

A fuel cell stack includes single cells stacked in a first direction. Each single cell includes a power generating unit, a first separator, and a second separator. The first separator and the second separator hold the power generating unit between the first separator and the second separator. The first separator of each single cell includes first protrusions. The second separator of each single cell includes second protrusions. A distal end of each second protrusion includes a depression that is located at a center in a second direction and extends in a third direction. A length of the depression in the second direction is greater than a length of the first protrusion in the second direction. A distal end of each first protrusion is located inside the depression.