Fuel cell stack

The fuel cell stack is provided with an exhaust gas flow path that passes through the cell stack in the front-rear direction and discharges the reaction gas introduced into the plurality of power generation cells. The fuel cell stack is provided with a communication pipe that is disposed in the exhaust gas flow path and that has a first opening and a second opening that communicate with the upstream side and the downstream side of the exhaust gas flow path, respectively. The exhaust gas flow path has a reduced diameter portion in which the flow path area gradually decreases toward the outlet of the exhaust gas flow path, and the second opening communicates with the exhaust gas flow path between the small-diameter-side end of the reduced diameter portion and the outlet of the exhaust gas flow path. 在燃料电池堆设置在前后方向上贯通电池层叠体以将导入到多个发电电池的反应气体排出的废气流道。燃料电池堆具备配置于废气流道，并具有分别与废气流道的上游侧和下游侧连通的第一开口和第二开口的连通管。废气流道具有随着趋向废气流道的出口而流道面积逐渐缩小的缩径部，第二开口在缩径部的小径侧的端部与废气流道的出口之间与废气流道连通。