Patent ID: 7803490

Claim:
A direct methanol fuel cell comprising a unit cell having an electrolyte membrane, an anode on one surface of said electrolyte membrane, and a cathode on an other surface of said electrolyte membrane, said anode comprising an anode catalyst layer and an anode diffusion layer, said anode catalyst layer being in contact with a surface of said electrolyte membrane, said anode diffusion layer being in contact with a surface of said anode catalyst layer opposite to said surface of said anode catalyst layer in contact with said electrolyte membrane, wherein a methanol flux value J GDL of said anode diffusion layer and a methanol flux value J PEM of said electrolyte membrane satisfy the following relations: J GDL =1×10 −5 to 5×10 −4 mol/(cm 2 ·min.), (i) J PEM ≧2×10 −5 mol/(cm 2 ·min.), (ii) and J PEM ×J GDL ≦1×10 −8 [mol/(cm 2 ·min.)] 2 (iii).