1. Technical Field
The present disclosure relates to a fuel cell and a manufacturing method for a fuel cell.
2. Description of Related Art
A fuel cell is known, which includes a membrane electrode gas diffusion layer assembly provided with a step portion so that a cathode-side peripheral area of an electrolyte membrane is exposed, a pair of separators that sandwich the membrane electrode gas diffusion layer assembly, and a sealing member that is sandwiched between the pair of separators and bonded to the peripheral area of the electrolyte membrane. On both sides of a resin base material of the sealing member, adhesive layers are provided, respectively, and the adhesive layers are bonded to the pair of separators. Also, one of the adhesive layers is bonded to the electrolyte membrane (for example, see Japanese Patent Application Publication No. 2014-67689 (JP 2014-67689 A).
For the adhesive layers of the sealing member, for example, thermoplastic resin or thermosetting resin is used, and the adhesive layers are thermocompression bonded to the separators. In a case where the adhesive layers are made of thermoplastic resin, a part of the adhesive layer, which is bonded to neither the separator nor the electrolyte membrane, shrinks at the time of cooling after the thermocompression bonding, and tension could be applied to the electrolyte membrane. In a case where the adhesive layer is thermosetting resin, the part of the adhesive layer shrinks at the time of cooling after thermosetting, and a similar problem could happen. Also, in a case where such a fuel cell stack is placed under a low-temperature environment, the part of the adhesive layer shrinks, and a similar problem could occur.