Abstract:
An method for producing a material useful for forming a component for an electrochemical fuel cell is provided. More particularly, the component is formed of a sheet of a compressed mass of expanded graphite particles. The component is treated with a water resistant additive sufficient to provide utility as a component in an electrochemical fuel cell. Preferably, the water resistant additive is a fluoropolymer material. More preferably, the water resistant additive is a polytetrafluoroethylene material. The treatment preferably occurs by coating and/or impregnating the water resistant material in the sheet of graphite particles.
Abstract:
A catalyst support material useful in a membrane electrode assembly is presented. The support catalyst material is elongate electrically anisotropic particles of flexible graphite, and the membrane electrode assembly includes a pair of electrodes, an ion exchange membrane having opposed surfaces positioned between the electrodes and a catalyst material on the inventive support, at least a portion of an opposed surface of the ion exchange membrane being adjacent the catalyst which is supported on the elongate electrically anisotropic particles of flexible graphite sheet.
Abstract:
Formable mixture of flexible graphite sheet particles having embedded ceramic fibers extending into the particles from the particle surfaces to increase the permeability of the sheet to resin.
Abstract:
Graphite flake is annealed at a temperature of at least about 3000null C. prior to intercalation. This annealing process results in enhanced expansion of intercalated graphite flake and provides uniform expansion of intercalated graphite flake derived from variety of sources.
Abstract:
The invention may be practiced to make graphite composites. Preferred composites which may be made in accordance with the invention include conductive polymeric composites (thermally or electrically), paint composites, battery composites, capacitor composites, and pollution abatement catalyst support composites. One method of making the graphite aforementioned composites includes introducing an intercalant into at least one interstice of at least one flake of natural graphite. The method also includes introducing a fluid into the at least one interstices of the flake. Preferably, the fluid comprises at least one of a sub-critical fluid, near critical point fluid, or a supercritical fluid. Furthermore the method includes blending the flake with a polymer, thereby forming a graphite-polymeric composite.
Abstract:
The invention relates to tubular fuel cells and methods of making such fuel cells. The inventive fuel cells include at least one fluid permeable structure having a plurality of perforations or channels. The perforations allow fluids, e.g., hydrogen or oxygen, to flow through the structure. The inventive methods include forming at least one perforated structure and forming the perforated structure into a tubular fuel cell or at least a potential component of a tubular fuel cell.
Abstract:
Graphite sheets having enhanced surface area are prepared from flexible graphite sheets to which an activated carbon precursor has been added, followed by activation of the precursor. The sheets with enhanced surface area are useful in the formation of articles adapted for use in supercapacitors.
Abstract:
The invention presented is a graphite article having predetermined anisotropic characteristics, as well as a process for preparing the article. More particularly, the article is prepared by a process involving determining the desired anisotropic characteristics for a finished flexible graphite article; intercalating and then exfoliating flakes of graphite to form exfoliated graphite particles; forming a substrate graphite article by compressing the exfoliated graphite particles into a coherent article formed of graphene layers; and producing a controlled directional alignment of the graphene layers in the substrate graphite article to provide a finished graphite article having the desired anisotropic ratio.
Abstract:
A process is presented for forming an anisotropic graphite article, comprising forming a laminate comprising a plurality of flexible graphite sheets which comprise graphene layers; and directionally aligning the graphene layers of the laminate.
Abstract:
Adhesive-backed graphite foil rings (62,64) are suited to forming a seal between a metal gasket plate (12) and adjacent pipe flanges (40, 42). To form the rings, a thin layer of adhesive (74) is applied in the form of a coating to a flexible graphite sheet (70). A release liner (80) may be applied over the adhesive layer. The rings (62,64) are cut from the adhesive coated flexible graphite sheet. In one method, the rings are die cut while leaving the release liner intact. After removal of extraneous material, a plurality of the rings remain attached to the release liner and can be peeled away from the liner as needed. In another method, a central cut-out portion (102) from a large adhesive-backed ring is later used to form a smaller adhesive-backed ring.