Fuel efficient membrane electrode assembly

Abstract

The present invention provides a fuel efficient membrane electrode assembly that substantially resists methanol from “crossing over” by sealing the anode diffusion layer and catalyst layer, and by preventing fluids from passing across at least a portion of the membrane electrolyte. The efficiency of the fuel cell is maintained because essentially all of the fuel is reacted on the catalyst layers creating electricity, which is transferred to the fuel cell load. The temperature of the fuel cell is also maintained as the uncatalyzed reaction that produces heat is prevented.

1 . A method of rendering a portion of a protonically-conductive membrane substantially liquid-impermeable including the step of rendering a portion of said protonically-conductive membrane, substantially liquid-impermeable by heat treatment. 
     
     
         2 . The method as defined in  claim 1  including the further step of rendering said portion of said protonically-conductive membrane substantially liquid-impermeable by using ultrasonic treatment techniques. 
     
     
         3 . The method as defined in  claim 1  including the further step of rendering said portion of said protonically-conductive membrane substantially liquid-impermeable by using selected chemical techniques. 
     
     
         4 . The method as defined in  claim 1  wherein said selected chemical techniques include amine dipping. 
     
     
         5 . The method as defined in  claim 1  including the further step of rendering peripheral edges of said protonically-conductive membrane substantially liquid-impermeable. 
     
     
         6 . The method as defined in  claim 1  including the further step of rendering peripheral edges of said protonically-conductive membrane substantially impermeable by painting an impermeable material along said peripheral edges. 
     
     
         7 . The method as defined in  claim 1  wherein said coating material includes TEFLON ®. 
     
     
         8 . The method as defined in  claim 1  including providing as said membrane, a membrane that is comprised substantially of NAFION®. 
     
     
         9 . The method as defined in  claim 1  including providing as said membrane, a membrane that includes a portion that has been rendered substantially protonically non-conductive.