Patent ID: 7666538

Claim:
A fuel cell device employing a fuel cell using liquid fuel, diluting said liquid fuel with dilution liquid and supplying said diluted liquid fuel to said fuel cell, wherein said fuel cell device comprises: said fuel cell; a first pump unit stacked on a fuel electrode side of said fuel cell, said first pump unit comprising: a first flat member comprising a liquid fuel supply passage and a dilution liquid supply passage that are in fluid communication with a mixing passage; a second flat member that has a first side in fluid communication with said fuel electrode side of said fuel cell and a second side opposite to said first side that is in fluid communication with said mixing passage, wherein said first pump unit supplies said diluted liquid fuel to a fuel electrode of said fuel cell while diluting said liquid fuel by mixing said liquid fuel and said dilution liquid together; a first pump formed by said first flat member and said second flat member, wherein said first pump supplies said liquid fuel to said mixing passage; a second pump formed by said first flat member and said second flat member, wherein said second pump supplies said dilution liquid to said mixing passage, wherein said first pump unit supplies said diluted liquid fuel to a fuel electrode of said fuel cell while diluting said liquid fuel by mixing said liquid fuel and said dilution liquid together; a second pump unit stacked on an air electrode side of said fuel cell, wherein said second pump unit comprises a third pump for collecting liquid produced by an electrochemical reaction in said fuel cell and liquid moving from said fuel electrode side of said fuel cell through an electrolyte layer of said fuel cell toward said air electrode side of said fuel cell.