Separator for fuel cell, fuel cell incorporating the same, and method of production of the same

摘要

An inexpensive and corrosion resistant metal-made gas separator(30) includes a base(60) formed by joining formed stainless steel base sheets face to face. The base(60) carries on each of opposite surfaces thereof a first coating layer(62) formed by plating with tin. The base is also coated with a second coating layer(64) of a thermal expansion graphite. When incorporated into a fuel cell, the separator contacts gas diffusion electrodes that are formed from a carbon material similar to the carbon material of the second coating layer(64), so that the contact resistance is reduced. The first coating layer is formed after a passive state coating is removed from the stainless steel surface, so that an increase in the internal resistance of the separator caused by the passive state coating is substantially prevented.