Wet seal for liquid electrolyte fuel cells

Claim 2

A FUEL CELL ELECTRODE COMPRISING AN ELECTRICALLYCONDUCTIVE MATERIAL HAVING A PERIPHERAL SEALING PORTION AND A CENTRAL ACTIVE PORTION, SAID ACTIVE PORTION INCLUDING A CATALYTIC SURFACE AND BEING POROUS TO THE TRANSMISSION OF GAS ANS SUBSTANTIALLY HYDROPHOBIC, SAID SEALING PORTION BEING HYDROPHILIC AND HAVING THE CAPABILITY OF RETAINING ELECTROLYTE THEREIN THROUGH ITS THICKNESS BY CAPILLARY ACTION, THEREBY PROVIDING A WET SEAL CAPABILITY IN SAID SEALING PORTION.

Claim 3

A fuel cell assembly for fuel cells utilizing gaseous reactants and a liquid electrolyte which comprises: a pair of fuel cell electrodes each comprising an electrically conductive material and having a peripheral portion and a central active portion, said active portion being porous to the transmission of gas and substantially hydrophobic, said peripheral portion of one of said electrodes being hydrophilic, said electrodes each having an inner surface and an outer surface, said active portion of said inner surface including a catalyst; a matrix sandwiched between said inner surfaces of said electrodes and including a peripheral sealing portion sandwiched between said peripheral portions of said electrodes and in contact therewith; a pair of gas separators, one positioned outwardly of each of said electrodes defining a gas space between the respective separators and the active portions of said electrodes, each of said separators having a peripheral portion one of which includes a sealing surface wettable by said electrolyte, said peripheral portions of said electrodes being sandwiched between said peripheral portions of said separators, said wettable sealing surface of said separator being in contact with said outer surface of Said hydrophilic peripheral portion of said electrode; and a liquid electrolyte, said electrolyte saturating said matrix between said inner surfaces of said electrodes and saturating said hydrophilic peripheral portion of said electrode through to said wettable sealing surface of said separator, said electrolyte being retained within said matrix and within said hydrophilic peripheral portion of said electrode by capillary action, said electrolyte forming a wet seal within said hydrophilic peripheral portion of said electrode and within said peripheral sealing portion of said matrix and between said hydrophilic peripheral portion of said electrode and said wettable sealing surface of said separator preventing the escape of gas thereby.

Claim 4

A fuel cell assembly for fuel cells utilizing gaseous reactants and a liquid electrolyte which comprises: a pair of fuel cell electrodes each comprising an electrically conductive material and having a peripheral portion and a central active portion, said active portion being porous to the transmission of gas and substantially hydrophobic, said peripheral portion of one of said electrodes being hydrophilic, said electrodes each having an inner surface and an outer surface, said active portion of said inner surface including a catalyst; a matrix sandwiched between said inner surfaces of said electrodes and including a peripheral sealing portion sandwiched between said peripheral portions of said electrodes and in contact therewith; a pair of gas separators, one positioned outwardly of each of said electrodes defining a gas space between the respective separators and the active portions of said electrodes, each of said separators having a peripheral portion one of which includes a sealing surface wettable by said electrolyte, said peripheral portions of said electrodes being sandwiched between said peripheral portions of said separators, said wettable sealing surface of said separator being in contact with said outer surface of Said hydrophilic peripheral portion of said electrode; and a liquid electrolyte, said electrolyte saturating said matrix between said inner surfaces of said electrodes and saturating said hydrophilic peripheral portion of said electrode through to said wettable sealing surface of said separator, said electrolyte being retained within said matrix and within said hydrophilic peripheral portion of said electrode by capillary action, said electrolyte forming a wet seal within said hydrophilic peripheral portion of said electrode and within said peripheral sealing portion of said matrix and between said hydrophilic peripheral portion of said electrode and said wettable sealing surface of said separator preventing the escape of gas thereby.

Claim 5

The fuel cell assembly according to claim 2 wherein said peripheral portion of both of said electrodes is hydrophilic and said peripheral portion of each of said separator plates includes a sealing surface wettable by said electrolyte.