摘要:
An electrocatalyst ink composition comprising a liquid vehicle, particles comprising at least one electrocatalyst metal, and at least one copolymer dispersant comprising at least one polyalkylene oxide segment.
摘要:
A process for preparing catalyst coated membranes and membrane electrode assemblies for use in direct methanol fuel cells is provided. Cathode and anode layers are formed by spraying catalyst-containing inks onto a novel framed electrolytic membrane to form a catalyst coated membrane. The spraying process optionally employs one or more masks, which carefully control where the catalyst-containing ink is deposited. Following application of the cathode and anode layers, diffusion layers are prepared and inserted onto the catalyst coated membranes, and pressed to form membrane electrode assemblies.
摘要:
A method for forming an electrically isolated via in a multilayer ceramic package and an electrical connection formed within the via are disclosed. The method includes punching a first via in a first layer, filling the first via with a cross-linkable paste, curing the paste to form an electrical insulator precursor and forming the via in the insulator precursor. The electrical connection formed includes an insulator made from a cross-linked paste supported by a substrate of a multilayer ceramic package and a conductive connection supported by the insulator.
摘要:
A method of producing a glass/metal package where a glass portion of the package is built up around a provided leadframe (10) using applications of solderable and glass pastes (20) which are subsequently fired (30). The glass paste and leadframe are chosen to have similar coefficients of expansion and the leadframe is pretreated to degasify and control oxidation of the metal to promote glass adhesion to the leadframe and prevent microcracking at a glass/metal interface. A seal ring is applied to the glass paste (40) and a lid is attached to the seal ring (50). The package is used to provide an sealed inert internal environment for sensitive electronic components such as a piezoelectric element. The package may be configured for leaded or surface mounting (60).
摘要:
Compositions and methods for the manufacture of electrodes for fuel cells. The compositions and methods are particularly useful for the manufacture of anodes and cathodes for proton exchange membrane fuel cells, particularly direct methanol fuel cells. The methods can utilize direct-write tools to deposit ink compositions and form functional layers of a membrane electrode assembly having controlled properties and enhanced performance.
摘要:
Compositions and methods for the manufacture of electrodes for fuel cells. The compositions and methods are particularly useful for the manufacture of anodes and cathodes for proton exchange membrane fuel cells, particularly direct methanol fuel cells. The methods can utilize direct-write tools to deposit ink compositions and form functional layers of a membrane electrode assembly having controlled properties and enhanced performance.
摘要:
Multiphase ceramic materials for use in multilayered device fabrication may be fabricated by providing novel glassy precursor materials of a preferred composition, with operable amounts of a non-glassy filler materials. The combined materials are fired at appropriate temperatures, so that a non-glassy anorthite type phase is formed. Material so fabricated is formed in a self-limiting process, in that reaction between the glassy precursor material and the non-glass filler material is terminated when one constituent of the glassy precursor material is fully consumed. The materials of the instant invention, fabricated according to the method disclosed herein, demonstrate excellent dielectric constant, and electrical loss characteristics.
摘要:
Compositions and methods for the manufacture of electrodes for fuel cells. The compositions and methods are particularly useful for the manufacture of anodes and cathodes for proton exchange membrane fuel cells, particularly direct methanol fuel cells. The methods can utilize direct-write tools to deposit ink compositions and form functional layers of a membrane electrode assembly having controlled properties and enhanced performance.
摘要:
An electrocatalyst ink composition comprising a liquid vehicle, particles comprising at least one electrocatalyst metal, and at least one copolymer dispersant comprising at least one polyalkylene oxide segment.
摘要:
A membrane electrode assembly comprises (a) a solid electrolyte polymer membrane; (b) an anode electrocatalyst layer disposed at one surface of the membrane and comprising a first electrocatalyst composition comprising carbon substrate particles and nanoparticles comprising an alloy of platinum and ruthenium disposed on the surface of the substrate particles; (c) a cathode electrocatalyst layer disposed at an opposite surface of the membrane, the cathode layer comprising a second electrocatalyst composition different from the first electrocatalyst composition and comprising carbon substrate particles and nanoparticles comprising platinum disposed on the surface of the substrate particles; and (d) gas diffusion layers disposed over each of the anode and cathode electrocatalyst layers. When operating in a direct methanol fuel cell with an active area of 25 cm2 and under conditions including a supply of 1M methanol to the anode electrocatalyst layer at a rate of 3 ml per minute, a supply of air to the cathode electrocatalyst layer at a rate of 400 sccm, the membrane electrode assembly provides an output voltage of 0.4 volt and a temperature of 70° C., provides a power output in excess of 120 mW/cm2 and a normalized performance in excess of 34 mW/mgPt.