GAS PASSAGE FORMATION PLATE FOR FUEL BATTERY AND FUEL BATTERY STACK

PROBLEM TO BE SOLVED: To enable improvement of power generation efficiency even in a power generation state in which a flow rate of gas is low.SOLUTION: A gas passage formation plate 22 is formed of a metal plate and is interposed between a membrane electrode assembly 13 and a flat plate-like flat separator 21, and constitutes a first separator 20 for a unit cell 10 of a fuel battery. The gas passage formation plate comprises: a plurality of gas passages 25 each having a recessed groove shape, which are formed on a surface opposite to the membrane electrode assembly 13 and extend in parallel with each other; and a plurality of water passages 26 each having a recessed groove shape, which are formed on the rear faces of inside projections 23 located between the two gas passages 25 adjacent to each other, respectively. In each inside projection 23, a plurality of communication paths 27 making the gas passages 25 communicate with the water passages 26 are formed. On a bottom face of each gas passage 25, a guide part 28 that further projects toward the downstream side in a flow direction of oxidant gas flowing in the gas passage 25 and guides the oxidant gas toward the membrane electrode assembly 13.SELECTED DRAWING: Figure 1 【課題】ガスの流量が少ない発電状態のときであっても発電効率を向上させることができる。【解決手段】ガス流路形成板２２は、金属板材により形成され、膜電極接合体１３と平板状のフラットセパレータ２１との間に介設されて燃料電池の単セル１０の第１セパレータ２０を構成するものであり、膜電極接合体１３に対向する面に形成され、互いに平行に延びる凹溝状の複数のガス流路２５と、隣り合う２つのガス流路２５の間にそれぞれ位置する内側突条２３の裏面に形成された複数の凹溝状の水流路２６と、を備える。内側突条２３には、ガス流路２５と水流路２６とを連通する複数の連通路２７が形成され、ガス流路２５の底面には、ガス流路２５を流れる酸化剤ガスの流れ方向の下流側ほど突出して酸化剤ガスを膜電極接合体１３に向けて案内する案内部２８が形成されている。【選択図】図１