1002 results about "Direct methanol fuel cell" patented technology

Fuel supplies for fuel cells are disclosed. The fuel supplies can be a pressurized or non-pressurized cartridge that can be used with any fuel cells, including but not limited to, direct methanol fuel cell or reformer fuel cell. In one aspect, a fuel supply may contain a reaction chamber to convert fuel to hydrogen. The fuel supplies may also contain a pump. The fuel supply may have a valve connecting the fuel to the fuel cell, and a vent to vent gas from the fuel supply. Methods for forming various fuel supplies are also disclosed.

The invention concerns a membrane electrode unit (MEU) for electrochemical equipment, especially for membrane fuel cells. The membrane electrode unit has a “semi-coextensive” design and contains an ionically conductive membrane, two catalyst layers, and gas distributor substrates of different sizes on the front and back sides. The first gas distributor substrate has smaller surface dimensions than the ionically conductive membrane, while the second gas distributor substrate has the same area as the ionically conductive membrane. The membrane electrode unit has, because of its special design, a stable structure that can be handled well, and which exhibits advantages for sealing the reactive gases off from each other and in its electrical properties. In particular, the hydrogen penetration current is distinctly reduced. The membrane electrode unit is used in PEM fuel cells, direct methanol fuel cells, electrolyzers, and other electrochemical equipment.

The present invention discloses a novel electrode-catalyst for direct methanol fuel cell prepared by introducing a carbon precursor into pores of a wormhole-like molecular sieve template, carbonizing the carbon precursor, removing the molecular sieve template to obtain a wormhole-like mesoporous carbon having a high specific surface of 800-1000 m2 / g and a pore size of 4-5 nm, and depositing catalyst metal such as Pt—Ru on the mesoporous carbon.

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.

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.

A water insoluble interpenetrating polymer network is obtained by independently cross-linking a first polymer derived from a sulfonic acid or phosphonic acid group containing alkenyl monomer and a second polymer polymerized independently of the first polymer and interpenetrating the first polymer, where the second polymer is selectively permeable to water compared to methanol. Through adjustment of the degree of first polymer monomer acidification, polymer ratios and the extent of cross-linking in the at least two interpenetrating polymers, ion conductivity and solvent permeability are controlled. A film produced from such a water insoluble interpenetrating polymer network is well suited as a membrane in a direct methanol fuel cell. The relative degree and mechanism of cross-linking and interpenetrating the first polymer and second polymer are also adjustable parameters that impact on film properties.

A compact, lightweight direct methanol fuel cell unit includes a circular membrane electrode assembly (MEA) having a cathode, a proton exchange membrane (PEM), and an anode, an air flow duct on the cathode side of the MEA, an annular fuel reservoir on the anode side of the MEA which contains a mixture of methanol and water as fuel, a carbon dioxide (CO.sub.2) relief valve communicating with the fuel reservoir, and a control unit. Due to the CO.sub.2 release mechanism, the fuel cell is completely self-sustaining without the need for a mechanical auxiliary system. Additionally, the control unit improves the stability of the fuel cell power output and the catalysis activity of the MEA. Another embodiment of the present invention is a direct methanol fuel cell system which incorporates a number of MEAs and a fuel cell reservoir. All the cathodic electrical terminals of the MEAs are serially connected together while they are electronically communicating with the control unit. The anodic electrical terminals similarly communicate electronically with the control unit. Higher power and voltage are thus attained while maintaining a compact size of the fuel cell system.

A fuel cell diffusion layer providing a preferential path by which liquid reactants or byproducts may be supplied to or removed from a direct oxidation fuel cell is described. The modified diffusion layer will be typically on the cathode side of the fuel cell and its use is to eliminate or minimize flooding of the cathode diffusion layer area, which is a performance limiting condition in direct methanol fuel cells. In accordance with one embodiment of the invention, the diffusion layer includes a substrate that is coated with a microporous layer. A pattern may be embossed into the diffusion layer, to create preferential flow paths by which water will travel and thereby be removed from the cathode catalyst area. This avoids cathode flooding and avoids build up of potentially destructive pressure by possible cathodic water accumulation. This also provides a means for collecting cathode water for redirection In accordance with another aspect of the invention, the preferential path is established by applying a thicker microporous layer to the carbon cloth or carbon paper and drying it in such a fashion so that when it dries, the surface of the microporous layer cracks to provide the pathways.

A flat panel DMFC (direct methanol fuel cell) includes an integrated cathode electrode sheet, a set of membrane electrode assemblies, an intermediate bonding layer, an integrated anode electrode sheet, and a fuel container base. The integrated cathode / anode electrode sheets are manufactured by using PCB compatible processes.

Fuel supplies for fuel cells are disclosed. The fuel supplies can be a pressurized or non-pressurized cartridge that can be used with any fuel cells, including but not limited to, direct methanol fuel cell or reformer fuel cell. In one aspect, a fuel supply may contain a reaction chamber to convert fuel to hydrogen. The fuel supplies may also contain a pump. The fuel supply may have a valve connecting the fuel to the fuel cell, and a vent to vent gas from the fuel supply. Methods for forming various fuel supplies are also disclosed.

A lightweight direct methanol fuel cell unit (20) comprising a fuel cell stack (24) enclosed within a housing (22). In one embodiment the fuel cell stack includes a plurality of polymer electrolyte membrane electrode assemblies (52) stacked alternatingly with a plurality of bipolar plates (48). Each bipolar plate includes a cathode flow field (78) defined by a porous cathode flow field structure (56) and an anode flow field (62) defined by an upper plate (58) and a lower plate (60) separated from one another by a plurality of spacers (64). The anode flow fields are manifolded with one another via manifold embossments (118, 120) that are hermetically sealed with one another with a gasket (126). The fuel cell stack and housing are shaped so as to form four manifold regions (36) in the spaces between the fuel cell stack and housing. The fuel cell stack is compressed within the housing by compression members (94) located between the fuel cell stack and housing so as to place the sidewall (30) of the housing into tension. Supporting systems for the fuel cell unit include a fuel handling system (502), an oxidant handling system (600), and a liquid inventory control system (700).

A composition useful in electrodes provides higher power capability through the use of nanoparticle catalysts present in the composition. Nanoparticles of transition metals are preferred such as manganese, nickel, cobalt, iron, palladium, ruthenium, gold, silver, and lead, as well as alloys thereof, and respective oxides. These nanoparticle catalysts can substantially replace or eliminate platinum as a catalyst for certain electrochemical reactions. Electrodes, used as anodes, cathodes, or both, using such catalysts have applications relating to metal-air batteries, hydrogen fuel cells (PEMFCs), direct methanol fuel cells (DMFCs), direct oxidation fuel cells (DOFCs), and other air or oxygen breathing electrochemical systems as well as some liquid diffusion electrodes.

The invention relates to a preparation method of a nanometer Pd or the Pd platinum gold electrocatalysis catalyzer which is used in a kind of fuel cell, whose characteristic lies in that dissolve the mixture of the ration Pd salt or the Pd salt and the platinum salt (in which the Pd atomic ratio accounts for metal quantity 10-100%) in the water, after joining the right amount complexing agent solution, elevates temperature to 0-80deg.C and keeps the temperature 5 minutes to 8 hours, then cooling to the room temperature, adjusts the pH value to 5 to 12 and adds the carbon carrier, then adds the solution of hydroboration sodium, hydrazine or formic acid and so on reducing agent under the 0 to 80deg.C , and maintains 10 minutes to 10 hours, then filtrating, laundering, dry, finally in inert atmosphere or reducing atmosphere through 100 to 300deg.C heat treatment in 0.5 to 10h, namely carries the carbon Pd or the Pd platinum electrocatalysis. The particle size of catalyst is controllable, adjustable, the composition is controllable, regards the heat treatment temperature to be different, the particle size which obtains is relatively 1.8nm to 20nm above, and the granule distribution is narrow, is suitable to serve as the direct formic acid fuel cell anode catalyst as well as the direct methanol fuel cell anti-methyl alcohol negative pole catalyst.

A flat panel direct methanol fuel cell (DMFC) includes an integrated cathode electrode plate, a set of membrane electrode assemblies, an intermediate bonding layer, an integrated anode electrode plate, and a fuel container base. The integrated cathode / anode electrode plates are conducive to mass production, and are manufactured by using PCB compatible processes.

A compact water management module for a direct methanol fuel cell (DMFC) system is provided. The module is a set of plates, typically two or more plates. Two of the plates are sandwiched together and enclose a membrane. The membrane is permeable to air or to water vapor. In another embodiment, both membranes are utilized. The cathode output stream of the DMFC stack feeds into one of the plates. One output of the module is water that is re-used as anode input stream to the DMFC stack. Another output of the module is the unused air that is vented out. The module is an elegant solution that improves the overall efficiency of a DMFC system. In addition, the module is small in size and can easily be stacked and integrated with a DMFC stack, a mixing device, a carbon dioxide separation device and / or a methanol source.

The invention provides a method for preparing carbon-supported nucleocapsid type Ni-Pt particles for direct methanol fuel cell catalysts, which belongs to a preparation process of direct methanol fuel cell catalysts. The method comprises the steps of adopting sodium citrate as a stabilizer, adopting cationic surfactant CTAB as dispersant, using sodium hypophosphite to reduce nickel acetate, generating a Ni kernel on the surface of Vulcan XC-72 or mesoporous carbon treated with sodium borohydride, washing superfluous sodium hypophosphite and generating a Pt shell on the surface of the Ni kernel through chemical replacement. The catalyst has a structure with the Ni kernel and the Pt shell, and has the advantages of low Pt support amount and high catalytic activity.

An electro-catalyst composition for use as an electrode, gas diffusion layer-supported electrode, catalytic electrode-coated solid electrolyte layer, and / or membrane-electrode assembly in a proton exchange membrane (PEM) type fuel cell. The composition comprises: (a) a proton- and electron-conducting polymer having at least one heteroatom per backbone monomer unit thereof and a plurality of neutral transition metal atoms covalently bonded to at least a portion of the heteroatoms; wherein the polymer has an electronic conductivity no less than 10−4 S / cm and a proton conductivity no less than 10−5 S / cm. Preferably, the electro-catalyst composition further comprises (b) a plurality of catalytically active particles of a transition metal, nucleated around the covalently bonded transition metal atoms. Also preferably, additional catalytically active catalyst particles with an average dimension smaller than 2 nm (most preferably smaller than 1 nm) are physically dispersed in such a polymer and typically not chemically bonded thereto. A hydrogen-oxygen PEM fuel cell or a direct methanol fuel cell (DMFC) featuring such an electro-catalyst composition in a thin-film electrode exhibits a superior current-voltage response.

The invention relates to the following: a method for step-by-step alkylation of primary polymeric amines by step-by-step deprotonation with a metallo-organic base and a subsequent reaction with an alkyl halide; a method for modifying tertiary polymeric amines with other functional groups; polymers with secondary / tertiary amino groups and with quaternary ammonium groups; polymers with secondary / tertiary amino groups and other functional groups, especially cation exchanger groupings; membranes consisting of the above polymers, either non-crosslinked or ionically or covalently cross-linked; acid-base-blends / membranes, and a method for producing same, consisting of basic polymers with polymers containing sulphonic acid, phosphonic acid or carboxyl groups; the use of ion exchanger polymers as membranes in membrane processes, e.g., polymer electrolyte membrane fuel cells, direct methanol fuel cells, redox batteries, or electrodialysis; the use of the inventive hydrophilic polymers as membranes in dialysis and reverse osmosis, nanofiltration, diffusion dialysis, gas permeation, pervaporation and perstraction.

A proton exchange membrane fuel cell and a direct methanol fuel cell pack using a monopolar electrode are provided. The fuel cell pack includes a plurality of cells each having a membrane in its middle and a cathode and an anode at both sides of the membrane, collector plates contacting the cathode and the anode, respectively, in each cell, and an electrical connection member for electrically connecting adjacent cells. The cells are evenly disposed on an arbitrary plane with a hollow interposed between two adjacent cells. The electrical connection member is positioned in the hollow. The fuel cell pack also includes a porous fuel diffusion member contacting the anode of each cell; a porous air contact member contacting the cathode of each cell; an anode end plate and a cathode end plate disposed at the side of the anodes of the cells and at the side of the cathodes of the cells, respectively, for protecting the cells; a fuel supply and discharge unit for supplying fuel toward the anodes in the hollow and discharging the fuel; a fuel flow stopper disposed at a portion at the part of the cathodes in the hollow, for preventing fuel flowing at a portion at the part of the anodes in the hollow from flowing toward the portion at the part of the cathodes in the hollow; and a sealing member for sealing the anodes of the cells and the portion of the hollow corresponding to the anodes. Accordingly, circulation of fuel for the plurality of cells is performed through a single inlet and a single outlet so that a fuel supply line is very simple compared to a structure of a fuel supply line for each cell in a conventional cell pack having a structural limitation. In addition, the cell pack generates current of a high density without a separate cooling device.

The invention discloses a preparation method of a proton exchange membrane used for a direct methanol fuel cell. The method is realized by that polyether ether ketone is added into concentrated sulfuric acid to carry out sulfonation reaction, thereby obtaining sulfonated polyether ether ketone, then the sulfonated polyether ether ketone is dissolved in organic solvent, N, N (1)-Carbonyldiimidazole is added to stir for one to three hours, coupling agent is mixed for stirring the reaction for 1.5 to 4 hours, then inorganic crosslinking agent is mixed to react under the temperature of 50 to 80 DEG C. Proton conductors are mixed to continue getting the mixed solution of the sulfonated polyether ether ketone or the inorganic crosslinking agent or proton conductors under the temperature. Finally the proton exchange membrane for a direct methanol fuel cell is obtained by that the mixed solution of the sulfonated polyether ether ketone or the inorganic crosslinking agent or proton conductors is / are processed through membrane forming, drying and exuviation. The membrane has the advantages of good methanol diffusion resistance, low cost, high proton conductivity and good water-resistant swelling performance under high temperature. The preparation method is simple, the raw materials have low price, and the production cost is low.

A DMFC (direct methanol fuel cell) includes two bipolar plates, a membrane electrode assembly, a bonding layer, and a fuel container base. The bipolar plate is a releasable substrate that includes a releasable copper carrier, a release layer, and a metal foil. The bipolar / MEA assembly is formed by laminating the releasable bipolar, the MEA, and the bonding sheet, peeling off the release carrier, and printing a carbon ink or plating Au.

The invention discloses a preparation method of PtRu / graphene nano electro-catalyst, comprising the following steps of: ultrasonically dispersing oxidized nano graphite sheets into liquid polylol; then adding a chloroplatinic acid solution and a sodium acetate solution, sufficiently mixing, wherein the content of the oxidized nano graphite sheets contained in a mixture is 0.3-1.1 g / L, the concentration of chloroplatinic acid is 0.0004-0.002 mol / L, the concentration of ruthenium chloride is 0.0004-0.0013 mol / L, and the concentration of sodium acetate is 0.005-0.027 mol / L; transferring the mixture to a microwave hydro-thermal reaction kettle for microwave hydro-thermal reaction for 5-10 minutes; and filtering, washing and drying to obtain the PtRu / graphene nano electro-catalyst, wherein the mass fraction of a PtRu alloy contained in the PtRu / graphene nano electro-catalyst is 20-40 percent, the mass fraction of graphene is 80-60 percent, the atomic ratio of the PtRu alloy is Pt:Ru=1:2-1.5:1, and the liquid polylol is propanetriol or glycol. The preparation method has energy saving, fastness, simple process, and the like; and in addition, the prepared PtRu / graphene nano electro-catalyst has good electrocatalysis property for the oxidation of methanol and ethanol and is widely used as anode catalysts of direct methanol fuel cells.

The invention discloses a preparation method of a two-dimensional titanium carbide / carbon nanotube loaded platinum particle composite material. The preparation method comprises the following steps: preparing two-dimensional titanium carbide by chemically peeling off an aluminum atomic layer in Ti3AlC2 by means of HF; and combining the two-dimensional titanium carbide with MWNTs by means of a solvothermal method, and meanwhile, loading the platinum nanoparticles to obtain the Ti3C2 / MWNTs-Pt nano composite material. The preparation method provided by the invention is simple, controllable in process, good in repeatability and low in cost, and industrial production on a large scale is facilitated. The prepared Ti3C2 / MWNTs-Pt nano composite material is large in specific surface area and good in electric conductivity, can be used as an anode catalyst of a direct methanol fuel cell, and shows excellent catalytic activity on methanol oxidation.

A gas diffusion cathode for electrochemical cells provides higher power capability through the use of nano-particle catalysts. The catalysts comprise nanometer-sized particles of transition metals such as nickel, cobalt, manganese, iron, palladium, ruthenium, gold, silver, and lead, as well as alloys thereof, and respective oxides. These catalysts can substantially replace or eliminate platinum as a catalyst for oxygen reduction. Cathodes using such catalysts have applications to metal-air batteries, hydrogen fuel cells (PEMFCs), direct methanol fuel cells (DMFCs), direct oxidation fuel cells (DOFCs), and other air breathing electrochemical systems.

An object of the present invention is to provide a proton conducting polymer membrane that has excellent mechanical properties and high methanol barrier properties, in addition to high proton conductivity, and is useful as an electrolyte in polymer electrolyte fuel cells and direct methanol fuel cells. The present invention provides a proton conducting polymer membrane having a product of a proton conductivity at 23° C. and a methanol barrier coefficient at 25° C. in an aqueous methanol solution of a specified concentration being a specified value or more. The present invention also provides a proton conducting polymer membrane having an ion exchange capacity of 0.3 milli-equivalent / g or more, and having a crystalline phase.

The present invention provides a system and method for passive thermal-fluids management in a liquid feed fuel cell. In particular, the present invention provides a system and method for passive thermal-fluids management in a direct methanol fuel cell having a methanol storage medium and a methanol and water mixing medium. The fuel cell may also include a methanol distribution medium that facilitates uniform distribution of methanol to the mixing medium and the anode, wherein the methanol and water are used for fuel by the direct methanol fuel cell.

The invention discloses a Pt-CeO2 / graphene electro-catalyst which uses graphene as a carrier, platinum as an active component and CeO2 as an auxiliary component, wherein the mass fraction of the platinum contained in the Pt-CeO2 / graphene electro-catalyst is 20 percent; and the mole ratio of the platinum and cerium is 1:1-2.5:1. A preparation method of the Pt-CeO2 / graphene electro-catalyst comprises the following steps of: ultrasonically dispersing oxidized nano graphite sheets into glycol; then adding a chloroplatinic acid solution, an aqueous ammonium ceric nitrate solution and an aqueous sodium acetate solution, and sufficiently mixing; transferring a mixture to a microwave hydro-thermal reaction kettle; and after microwave hydro-thermal reaction, filtering, washing and drying to obtain the Pt-CeO2 / graphene electro-catalyst. The preparation method has energy saving, fastness, simple process, and the like; and in addition, the prepared Pt-CeO2 / graphene electro-catalyst has high electrocatalysis activity for the electrochemical oxidation of methanol and is widely used for direct methanol fuel cells.

The invention provides a preparation method for a double-catalyst layer membrane electrode of a direct methanol fuel cell. The aims of the invention are realized by the following steps: firstly, a non-load inner catalyst layer is directly formed on the surface of a proton exchange membrane, and a CCM membrane electrode is prepared; secondly, an outer catalyst layer, namely a load catalyst outer electrode which contains carbon medium load, is prepared by adoption of GDE method; thirdly, heat pressing of the two electrodes is performed, and the highly efficient double-catalyst layer membrane electrode is obtained. The invention is suitable for the direct methanol fuel cell; the preparation method is simple; the electrode can be mass produced; use amount of catalyst can be effectively reduced; utilization rate of noble metals is improved; the invention is characterized in the double-catalyst layer electrode structure.

The present invention relates to a small fuel cell and a small fuel cell stack each allowing for improved output. Conventionally, in a direct methanol fuel cell, carbon dioxide gas produced at an anode electrode side is exhausted together with a methanol aqueous solution. From the methanol aqueous solution, the carbon dioxide gas is separated, and then the methanol aqueous solution is reused as fuel. In this case, a liquid-gas separation device needs to be provided additionally, which results in a large fuel cell with an increased weight, disadvantageously. The present invention is made to solve such a problem by providing a fuel cell including a first unit cell having a cathode electrode, an electrolyte membrane, an anode electrode, and an anode collector layer in this order; and one or more spacers arranged on the anode collector layer. The anode collector layer has a fuel flow path for supplying fuel to the anode electrode, and a through hole for exhausting a reaction product generated by reaction in the anode electrode. Each of the spacers has an exhaust flow path for exhausting the reaction product to outside the fuel cell. The through hole and the exhaust flow path communicate with each other.