| US 7,592,092 B2 | ||
| Fuel cell having a hydrogen electrode catalyst layer porosity that is lower than the air electrode catalyst layer porosity | ||
| Sozaburo Ohashi, Nagoya (Japan) | ||
| Assigned to Toyota Jidosha Kabushiki Kaisha, Toyota (Japan) | ||
| Appl. No. 10/562,970 PCT Filed Nov. 24, 2004, PCT No. PCT/JP2004/017825 § 371(c)(1), (2), (4) Date Dec. 29, 2005, PCT Pub. No. WO2005/057698, PCT Pub. Date Jun. 23, 2005. |
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| Claims priority of application No. 2003-413680 (JP), filed on Dec. 11, 2003. | ||
| Prior Publication US 2006/0166073 A1, Jul. 27, 2006 | ||
| Int. Cl. H01M 4/90 (2006.01) | ||
| U.S. Cl. 429—41 [429/40] | 6 Claims |
| 1. A fuel cell having at least a membrane electrode assembly comprising:
an electrolyte membrane;
a hydrogen electrode-side catalyst layer formed on one side thereof; and
an air electrode-side catalyst layer formed on the other side thereof,
wherein a porosity of the hydrogen electrode-side catalyst layer is lower than a porosity of the air electrode-side catalyst
layer, a volume of pore space of the hydrogen electrode-side catalyst layer has a range of 1.0% to 3.0% of a total volume
of the catalyst layer, and a volume of pore space of the air electrode-side catalyst layer has a range of 3% to 30% of the
total volume of the catalyst layer,
wherein the hydrogen electrode-side catalyst layer contains an additive having an average particle diameter less than or equal
to 0.3 μm and the porosity of the hydrogen electrode-side catalyst layer is lower than the porosity of the air electrode-side
catalyst layer, and
wherein the additive is selected from titanium oxide, zinc oxide, and cerium oxide.
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