Fuel cell stack with polymer electrolyte

摘要

A fuel cell (10) wherein (a) an MEA and a separator (18) are layered in a direction perpendicular to gravity, and (b) a fuel gas inlet (27b), a fuel gas outlet (27c) and a fuel gas passage (27a), and an oxidant gas inlet (28b), an oxidant gas outlet (28c) and an oxidant gas passage (28a) are arranged such that a humidity distribution of fuel gas at an anode (14) and a humidity distribution of oxidant gas at a cathode (17) are counter to each other. The fuel cell (10) has a coolant passage (26), and the humidity distribution and a temperature distribution at the cathode (17) correspond to each other. Each gas passage (27a, 28a) has a concave portion (29) at a lower wall thereof.