Fuel Cell Anode Structures For Voltage Reversal Tolerance

Abstract

A voltage reversal tolerant fuel cell anode structure that includes a gas diffusion layer is prepared by a method that comprises: (a) applying to the gas diffusion layer a first carbon component comprising a sacrificial carbon component having substantially no resistance to corrosion during cell reversal at fuel cell operating temperatures, and (b) applying to the gas diffusion layer a second carbon component. The first carbon material has a BET surface area of at least 350 m 2 g −1 . The second carbon component supports an electrocatalyst material and has substantially more resistance to corrosion during cell reversal at fuel cell operating temperatures than the first carbon component.

1 . A method of preparing a voltage reversal tolerant fuel cell anode structure comprising a gas diffusion layer, the method comprising:
 (a) applying to said gas diffusion layer a first carbon component comprising a sacrificial carbon component having substantially no resistance to corrosion during cell reversal at fuel cell operating temperatures and said first carbon material having a BET surface area of at least 350 m 2 g −1 ,   (b) applying to said gas diffusion layer a second carbon component, said second carbon component supporting an electrocatalyst material, said second carbon component having substantially more resistance to corrosion during cell reversal at fuel cell operating temperatures than said first carbon component.   
     
     
         2 . The method of  claim 1  wherein said first carbon component and said second carbon components are mixed before applying to said gas diffusion layer. 
     
     
         3 . An improved method of imparting voltage reversal tolerance to a fuel cell anode structure comprising a gas diffusion layer, said gas diffusion layer having an electrocatalytic material disposed on a carbon support applied thereto, the improvement comprising:
 applying to said gas diffusion layer a sacrificial carbon component having substantially no resistance to corrosion during cell reversal at fuel cell operating temperatures and having a BET surface area of at least 350 m 2 g −1 .   
     
     
         4 . A method of preparing a voltage reversal tolerant fuel cell anode structure comprising a gas diffusion layer, the method comprising:
 (a) incorporating into said gas diffusion layer a first carbon component comprising a sacrificial carbon component having substantially no resistance to corrosion during cell reversal at fuel cell operating temperatures and said first carbon material having a BET surface area of at least 350 m 2 g −1 ,   (b) incorporating into said gas diffusion layer a second carbon component, said second carbon component supporting an electrocatalyst material, said second carbon component having substantially more resistance to corrosion during cell reversal at fuel cell operating temperatures than said first carbon component.   
     
     
         5 . The method of  claim 4  wherein said first carbon component and said second carbon components are mixed before incorporation into said gas diffusion layer. 
     
     
         6 . An improved method of imparting voltage reversal tolerance to a fuel cell anode structure comprising a gas diffusion layer, said gas diffusion layer comprising an electrocatalytic material disposed on a carbon support, the improvement comprising:
 incorporating into said gas diffusion layer a sacrificial carbon component having substantially no resistance to corrosion during cell reversal at fuel cell operating temperatures and having a BET surface area of at least 350 m 2 g −1 .