Patent ID: 8278003

Claim:
A direct methanol fuel cell comprising: an anode to which an aqueous methanol solution is supplied as the fuel, a cathode to which oxidizing gas is supplied, an electrolyte membrane interposed between the anode and the cathode, a first separator disposed on the surface of the anode on the side opposite to the electrolyte membrane side and a second separator disposed on the surface of the cathode on the side opposite to the electrolyte membrane side, wherein the first and second separators are respectively made of a membrane containing a copolymer which is represented by the formula (I) below, and a carbon powder dispersed in the copolymer: wherein (i) R 1 represents an alkyl group having 1 to 20 carbon atoms, (ii) R 2 represents an aromatic group, and (iii) l, m and n denote the degrees of polymerization of the first, second and third monomers (1), (2) and (3), respectively: 1=10-300, m=150-600 and n=50-200.