Abstract: A method of manufacturing a fuel cell bipolar plate comprising first and second thermoformed plates. The thermoformed plates comprise at least one thermoplastic polymer. The method includes providing film cast resin mixture and forming it into a substantially flat sheet having first and second opposing major surfaces. The sheet may be preheated to a predetermined temperature and thermoformed thereby creating separator plates of a desired size and shape. First and second plates are joined to form an integral bipolar plate.

Abstract: New proton conducting membranes are made of perfluorosulfonic acid polymers films that have been treated by exposing them to a chlorosulfonating agent. The membranes are used as a proton exchange membrane in PEM fuel cells operating at temperatures above 95° C., or at low relative humidity. In various embodiments, the treated films have superior physical properties such as tensile strength, when compared to an untreated film. In some embodiments, the ion exchange capacity (IEC) of the treated films is increased.

Abstract: A method of enhancing electrical performance of a membrane for a fuel cell is disclosed. The method includes providing a perfluorosulfonic acid (PFSA) ionomer in an aqueous hydroxylated hydrocarbon aqueous solution. The PFSA dispersion or solution has an acid number the same or higher than an acid number of the membrane. The membrane is immersed in the solution such that the high acid number PFSA dispersion diffuses into the membrane. After immersion, the removed membrane is then dried under tension.

Abstract: A novel method of altering extruded membrane films for PEM (polymer electrolyte membrane) fuel cells in such a manner that the membrane films swell substantially uniformly in both the in-plane x and y directions when immersed in water or ionomer solution is disclosed. The invention includes cutting a membrane film from an extruded membrane sheet in a diagonal orientation with respect to the membrane process direction of the membrane sheet. The membrane film exhibits reduced internal stress as compared to conventionally-prepared membrane films and allows a more even distribution of pressure in a fuel cell stack, thereby reducing the incidence of swollen membrane-induced failure mechanisms in the fuel cell stack.

Abstract: New proton conducting membranes are made of sulfonated poly(arylene sulfide) polymers (SPAS) and a perfluorosulfonic acid polymer. A preferred poly(arylene sulfide) polymer is poly(p-phenylene sulfide). The membranes are used as a proton exchange membrane in PEM fuel cells operating at temperatures above 60° C., or at low relative humidity. According to methods of the invention, sulfonated poly(phenylene sulfide) (SPPS) films may be provided with a wide range of physical properties, which depend in part on the ion exchange capacity of the films. In particular, the degree or level of sulfonation can be tailored by adjusting reaction conditions such as temperature and time. In a preferred embodiment, an ionomer comprising perfluorosulfonic acid polymer is imbibed into the insoluble SPAS films by immersing the films in a solution or dispersion of the ionomers.

Abstract: A novel method of altering extruded membrane films for PEM (polymer electrolyte membrane) fuel cells in such a manner that the membrane films swell substantially uniformly in both the in-plane x and y directions when immersed in water or ionomer solution is disclosed. The invention includes cutting a membrane film from an extruded membrane sheet in a diagonal orientation with respect to the membrane process direction of the membrane sheet. The membrane film exhibits reduced internal stress as compared to conventionally-prepared membrane films and allows a more even distribution of pressure in a fuel cell stack, thereby reducing the incidence of swollen membrane-induced failure mechanisms in the fuel cell stack.

Abstract: Proton conducting membranes are made of sulfonated films comprising poly(arylene sulfide), an olefinic polymer, and an elastomer. They are used in PEM fuel cells operating at temperatures above 95° C., or at low relative humidity. According to methods of the invention, sulfonated poly(phenylene sulfide) (SPPS) films are provided with a wide range of physical properties, which depend in part on the ion exchange capacity of the films. In particular, the degree or level of sulfonation can be tailored by adjusting reaction conditions such as temperature and time.

Abstract: Proton conducting membranes are made of sulfonated films comprising poly(arylene sulfide), an olefinic polymer, and an elastomer. They are used in PEM fuel cells operating at temperatures above 95° C., or at low relative humidity. According to methods of the invention, sulfonated poly(phenylene sulfide) (SPPS) films are provided with a wide range of physical properties, which depend in part on the ion exchange capacity of the films. In particular, the degree or level of sulfonation can be tailored by adjusting reaction conditions such as temperature and time.

Abstract: A method of manufacturing a fuel cell bipolar plate comprising first and second thermoformed plates. The thermoformed plates comprise at least one thermoplastic polymer. The method includes providing film cast resin mixture and forming it into a substantially flat sheet having first and second opposing major surfaces. The sheet may be preheated to a predetermined temperature and thermoformed thereby creating separator plates of a desired size and shape. First and second plates are joined to form an integral bipolar plate.

Abstract: A method including providing an ion conductive membrane and deactivating a selected region of the membrane.