US RE42,434 E1
	Corrosion resistant PEM fuel cell
Matthew Howard Fronk, Honeoye Falls, N.Y. (US); Rodney Lynn Borup, East Rochester, N.Y. (US); Jay S. Hulett, Rochester, N.Y. (US); Brian K. Brady, North Chili, N.Y. (US); and Kevin M. Cunningham, Romeo, Mich. (US)
Assigned to GM Global Technology Operations LLC, Detroit, Mich. (US)
Filed on Nov. 21, 2003, as Appl. No. 10/720,005.
Application 10/720005 is a reissue of application No. 09/456478, filed on Dec. 07, 1999, now 6,372,376, filed on Apr. 16, 2002.
Int. Cl. H01M 4/86 (2006.01); H01M 2/14 (2006.01)

U.S. Cl. 429—529  [429/522; 429/530; 429/532; 429/479]

8 Claims

1. In a PEM fuel cell having at least one cell comprising a pair of opposite polarity electrodes, a membrane electrolyte intedacent [ interjacent ] said electrodes for conducting ions therebetween, and an electrically conductive contact element having a working face confronting at least one of said electrodessfor [ electrodes for ] conducting electrical current from said one electrode, the improvement comprising: said contact element comprising a corrosion-susceptible metal substrate and an electrically conductive, corrosion-resistant protective coating on said face to protect said substrate from the corrosive environment of said fuel cell, said protective coating comprising a mixture of electrically conductive particles dispersed throughout an oxidation-resistant and acid-resistant, water-insoluble polymeric matrix and having a resistivity [ no ] greater than about 50 ohm-cm, said mixture comprising graphite particles having a first particle size and other electrically conductive particles selected from the group consisting of gold, platinum, nickel, palladium, rhodium, niobium, titanium carbide, titanium nitride, titanium diboride, chromium-alloyed titanium, nickel-alloyed titanium, rare earth metals and carbon, said other particles having a second particle size less than said first particle size to enhance the packing density of said particles.