736results about "Aqueous electrolyte fuel cells" patented technology

A redox flow cell is presented that utilizes a porous membrane separating a first half cell and a second half cell. The porous membrane is chosen to have a figure of merit (FOM) is at least a minimum FOM. A method of providing a porous membrane for a flow cell can include determining a figure of merit; determining a first parameter from a pore size or a thickness for the porous membrane; determining a second parameter from the pore size or the thickness that is not the first parameter for the porous membrane, based on the figure of merit; and constructing a porous membrane having the pore size and the thickness.

An improved gas-diffusion cathode for use in an electrochemical cell comprising an electrically conductive cathode member having a first side communicable with an aqueous electrolyte and a second side communicable with a gaseous medium; and a water-impermeable membrane adjacent said cathode member second side to reduce passage of liquid water between said cathode member and said gaseous medium and having a membrane first side and a membrane second side wherein said membrane first side faces said cathode member and wherein said water-impermeable membrane comprises one or more portions defining one or more openable and closeable apertures the improvement wherein said apertures are associated with one or more integrally-formed resiliently flexible flaps on said membrane first side to effect said opening and closing. The batteries have reduced unwanted water vapour ingress and egress characteristics in its no-load mode.

A method for producing oxygen and absorbing carbon dioxide in a single operation using a solution that contains an oxygen source and a redox partner that can react to form oxygen and a chemical species that can form an insoluble carbonate to precipitate and chemically store carbon dioxide. Carbon dioxide is introduced into the solution and the carbonate precipitates as the oxygen is generated. In particular, the invention uses an aqueous solution of permanganate and hydrogen peroxide that react in the presence of a catalyst to produce oxygen and manganese (II) ions. Carbon dioxide gas introduced into the solution reacts with the manganese (II) ions to precipitate manganese carbonate. Other cations capable of reacting with carbon dioxide to form an insoluble carbonate, for example calcium, barium and magnesium, may also be added to the solution to precipitate carbonate salts. Calcium permanganate may used as a source of both calcium and permanganate.

The invention relates to electrolyte salts for electrochemical devices of improved physical, chemical and electrochemical stability.

• • The improvement resides in the use of anions of salts of the formula comprising: i) (B₁₂F_xZ_12-x)²⁻ wherein Z comprises at least one of H, Cl, Br or OR; R comprises at least one of H, alkyl or fluoroalkyl, or at least one polymer and x is at least 3 on an average basis but not more than 12;
  • ii) ((R′R″R′″)NB₁₂F_xZ_(11-x))⁻, wherein N is bonded to B and each of R′, R″, R′″ comprise a member independently selected from the group consisting of hydrogen, alkyl, cycloalkyl, aryl and a polymer; Z comprises H, Cl, Br, or OR, where R comprises H, alkyl or perfluoroalkyl or a polymer, and x is an integer from 0 to 11; or
  • iii) (R″″CB₁₁F_xZ_(11-x))⁻, wherein R″″ is bonded to C and comprises a member selected from the group consisting of hydrogen, alkyl, cycloalkyl, aryl, and a polymer, Z comprises H, Cl, Br, or OR, wherein R comprises H, alkyl or perfluoroalkyl or a polymer, and x is an integer from 0 to 11.

A fuel cell comprising: (a) a binary anode, (b) a cathode, and (c) a liquid electrolyte disposed between and interacting with the binary anode and the cathode, wherein the binary anode includes at least one liquid fuel and at least one solid fuel. Preferably, the electrolyte includes an alcohol such as methanol, and the solid fuel includes aluminum, magnesium and/or zinc.

An inexpensive, highly catalytic material preferably formed by a leaching process. The catalyst comprises a finely divided metal particulate and a support. The active material may be a nickel and/or nickel nickel alloy particulate having a particle size less than about 100 Angstroms. The support may be one or more metal oxides.

Systems and methods drawn to an electrochemical cell comprising a low temperature ionic liquid comprising positive ions and negative ions and a performance enhancing additive added to the low temperature ionic liquid. The additive dissolves in the ionic liquid to form cations, which are coordinated with one or more negative ions forming ion complexes. The electrochemical cell also includes an air electrode configured to absorb and reduce oxygen. The ion complexes improve oxygen reduction thermodynamics and/or kinetics relative to the ionic liquid without the additive.

The invention relates to platinum-metal oxide composite particles and their use as electrocatalysts in oxygen-reducing cathodes and fuel cells. The invention particularly relates to methods for preventing the oxidation of the platinum electrocatalyst in the cathodes of fuel cells by use of these platinum-metal oxide composite particles. The invention additionally relates to methods for producing electrical energy by supplying such a fuel cell with an oxidant, such as oxygen, and a fuel source, such as hydrogen.

A flow battery with thermal management is presented. The flow battery is housed in an enclosure where fluid is uniformly circulated about holding tanks of electrolyte to control the temperature inside the enclosure.

An electrode for use in a flow cell is presented. The electrode includes a metal plate for collecting current in the electrode that is bonded between a first and second plate.

A metal-air battery or fuel cell comprising a metal or metal hydride anode, an aqueous liquid electrolyte containing an ion conducting material, and an air electrode which allows ingress and egress of oxygen and which contains one or more catalysts capable of evolution and/or reduction of oxygen, wherein the air electrode has both hydrophobic and hydrophilic pores, the hydrophilic pores are at least partially filled with aqueous liquid electrolyte and the air electrode and/or the electrolyte comprises hygroscopic material and OH⁻ ions, whereby water vapour exchange with the environment is limited. The hygroscopic material is used to control the humidity of the system.

Processes, techniques, and compositions used to fabricate high performance solid acid fuel cell membrane electrode assemblies are disclosed. The techniques include preparing the solid acid electrolyte material, depositing the electrolyte membrane, depositing the electrocatalyst layer, preparing the electrodes, fabricating the gas seals, and constructing the membrane electrode assembly.

A hydrogen generation and storage method for producing and storing hydrogen at a home or business site that enables refueling hydrogen to a personal vehicle at a convenient location. The method comprises (a) operating a solar energy conversion subsystem to capture and convert solar radiation into both electrical energy and thermal energy; (b) operating a fuel cell electrolyzer that uses the converted electrical energy and thermal energy to split water into hydrogen and oxygen wherein the fuel cell electrolyzer operates at a temperature between 80° C. and 300° C.; and (c) operating a hydrogen storage means to store the generated hydrogen. The hydrogen storage means preferably comprises (1) a hydrogen storage container comprising a metal hydride, chemical hydride, or other solid or liquid phase material as a storage medium to capture and store the generated hydrogen; and (2) control means to regulate the uptake of hydrogen in the storage container.

A method and apparatus for generating energy from a composition comprising urea and water are described. The method in one embodiment includes: (a) reacting the urea with water to form ammonia; and (b) oxidizing the ammonia formed in step (a) to form water and nitrogen generating energy. The apparatus in one embodiment contains: (a) a first container for providing the composition; (b) a second container for reacting the urea with water to form ammonia, wherein the second container is connected to the first container by means for delivering the composition from the first container to the second container; (c) a third container for providing ammonia, wherein the third container is connected to the second container by means for delivering ammonia from the third container to the second container; and (d) a fourth container for oxidizing ammonia to form water and nitrogen generating energy, wherein the fourth container is connected to the second container by means for delivering ammonia from the second container to the fourth container. The method and apparatus are used to generate energy for use in stationary and mobile applications.

A method and apparatus for generating power from voltage gradients at sediment-water interfaces or within stratified euxinic water-columns is provided. Natural voltage gradients typically exist at and about sediment-water interfaces or in isolated water bodies. One electrode (anode) is positioned in the sediment or water just below the redox boundary and the other electrode (cathode) is positioned in the water above the redox boundary over the first electrode. The anode is lower in voltage than the cathode. Current will flow when the electrodes are connected through a load, and near-perpetual generating of worthwhile power may be sustained by the net oxidation of organic matter catalyzed by microorganisms.

A bipolar separator plate for a fuel cell stack constructed of at least two coextensive sheet metal elements shaped to promote the distribution of reactant gases to the electrodes of the fuel cell units of the fuel cell stack. The coextensive sheet metal elements are corrugated and fitted together to form at least one coolant flow channel between corresponding peaks, or valleys, of the corrugations of the sheet metal elements.