SEPARATOR FOR LOW TEMPERATURE TYPE FUEL CELL AND MANUFACTURING METHOD OF THE SAME

摘要

PROBLEM TO BE SOLVED: To provide a separator for a low temperature type fuel cell made to have low contact resistance and excellent corrosion resistant property by forming a dense barrier thin film on a stainless steel with roughened surface. SOLUTION: For the separator, many pits are formed on the whole surface of a stainless steel plate by surface roughening treatment, and the stainless steel plate has such a shape of surface that the periphery of the pits are bristled with fine projections, and dense barrier thin film is formed on the roughened surface by a passivation treatment after the roughening treatment. The separator is formed by applying passivation treatment like hydrofluoric acid and nitric acid bath or nitric acid bath after the surface roughening treatment.