Patent ID: 6841283

Claim:
A high water permeability proton exchange membrane ( 12 ) for use in an electrochemical cell, the membrane ( 12 ) comprising: a. between about 20 volume percent and about 40 volume percent of a structural insulating phase ( 40 ) selected from the group consisting of a particulate material, a whisker material, or a fibrous material, which materials are electronically non-conductive; b. between about 50 volume percent and about 70 volume percent of a hydrated nanoporous ionomer phase ( 42 ) consisting of a cation exchange resin; and, c. about 10 volume percent of a microporous water-filled phase ( 44 ) consisting of open pores having a diameter of between 0.3 and 1.0 microns defined within the hydrated nanoporous ionomer phase ( 42 ) so that water may flow through the open pores between a first catalytic surface ( 14 ) and an opposed second catalytic surfaces ( 16 ) of the high water permeability proton exchange membrane ( 12 ).