Electrolyte membrane for solid polymer fuel cell, method for manufacturing same, and solid polymer fuel cell
View Patent ↗A solid polymer fuel cell has a plurality of stacked single battery modules having an electrolyte membrane, electrode layers disposed on both surfaces of the electrolyte membrane, and a pair of separators provided with a gas flow paths disposed on the inside surface so as to sandwich the electrode layer. The electrolyte membrane is provided with electrolyte material and a nonwoven fabric which is embedded in the electrolyte material. The nonwoven fabric is provided with a plurality of fused parts that are provided in a linear shape or spotted on a part of the nonwoven fabric that is a part corresponding to of the solid polymer fuel cell. Two or more nonwoven fibers are fused to each other, and the thickness thereof is thinner than the membrane thickness of the unwoven fabric.
1. A polymer electrolyte fuel cell comprising:
a plurality of stacked cell modules, each of the cell modules including:
an electrolyte membrane;
electrode layers each provided on a respective one of an upper surface and a lower surface of the electrolyte membrane; and
a pair of separators sandwiching the electrode layers therebetween, each of the separators having an inner surface with a gas flow path thereon;
wherein the electrolyte membrane includes:
an electrolyte material;
a nonwoven fabric included in the electrolyte material; and
fibers in the nonwoven fabric,
wherein the nonwoven fabric includes a plurality of fused parts provided in straight lines or dots, all of the fused parts being equally spaced apart, each of the fused parts being formed of two or more strands of nonwoven fiber fused to each other, the fused parts having a thickness smaller than a thickness of the nonwoven fabric, a diameter of each of the fibers being in a range of from 400 nm to 1100 nm, and all of the fused parts extending along the gas flow path of the separators so as to impede expansion of the electrolyte membrane into the gas flow path;
wherein a percentage of an area of the fused parts provided in the straight lines or dots is in a range of from at least 0.5% to no greater than 10% of a total area of a part corresponding to a power generating region of the nonwoven fabric; and
wherein fused parts that are unequally spaced apart do not exist in the electrolyte membrane.
2. The polymer electrolyte fuel cell according to claim 1 , wherein a distance between all adjacent fused parts of all of the fused parts in the nonwoven fabric is at least 10 mm and no greater than 20 mm.
3. The polymer electrolyte fuel cell according to claim 1 , wherein all of the fused parts in the nonwoven fabric are formed in a grid pattern.
4. The polymer electrolyte fuel cell according to claim 1 , wherein all fused parts present within the nonwoven fabric are arranged in the straight lines or dots and are equally spaced apart.