The present invention is to provide a hydrogen oxidation catalyst that does not contain platinum. Disclosed is a hydrogen oxidation catalyst that is a dinuclear transition metal complex having a chemical structure represented by the following general formula (1) or (2): ##STR00001##
wherein, in the general formulae (1) and (2), M.sup.1 and M.sup.2 are each independently Fe or Ru; Ar.sup.1 and Ar.sup.2 are each independently a cyclopentadienyl group or a pentamethylcyclopentadienyl group; Ar.sup.3 and Ar.sup.4 are each independently a divalent aromatic hydrocarbon group having 6 to 12 carbon atoms; and Ar.sup.5 is a monovalent aromatic hydrocarbon group having 6 to 12 carbon atoms, and in the general formula (2), R.sup.1 and R.sup.2 are each independently a hydrogen atom or a monovalent aliphatic hydrocarbon group having 1 to 3 carbon atoms.

The present invention is to provide a hydrogen oxidation catalyst that does not contain platinum. Disclosed is a hydrogen oxidation catalyst that is a dinuclear transition metal complex having a chemical structure represented by the following general formula (1) or (2): ##STR00001##
wherein, in the general formulae (1) and (2), M.sup.1 and M.sup.2 are each independently Fe or Ru; Ar.sup.1 and Ar.sup.2 are each independently a cyclopentadienyl group or a pentamethylcyclopentadienyl group; Ar.sup.3 and Ar.sup.4 are each independently a divalent aromatic hydrocarbon group having 6 to 12 carbon atoms; and Ar.sup.5 is a monovalent aromatic hydrocarbon group having 6 to 12 carbon atoms, and in the general formula (2), R.sup.1 and R.sup.2 are each independently a hydrogen atom or a monovalent aliphatic hydrocarbon group having 1 to 3 carbon atoms.

Described herein are systems and methods for the management and control of electrolyte within confined electrochemical cells or groups (e.g. stacks) of connected electrochemical cells, for example, in an electrolyzer. Various embodiments of systems and methods provide for the elimination of parasitic conductive paths between cells, and/or precise passive control of fluid pressures within cells. In some embodiments, a fixed volume of electrolyte is substantially retained within each cell while efficiently collecting and removing produced gases or other products from the cell.

Described herein are systems and methods for the management and control of electrolyte within confined electrochemical cells or groups (e.g. stacks) of connected electrochemical cells, for example, in an electrolyzer. Various embodiments of systems and methods provide for the elimination of parasitic conductive paths between cells, and/or precise passive control of fluid pressures within cells. In some embodiments, a fixed volume of electrolyte is substantially retained within each cell while efficiently collecting and removing produced gases or other products from the cell.

Flow cell batteries and methods of producing an electric current are provided. In some implementations, a flow cell battery includes an electrochemical cell including an ion exchange membrane, an anode current collector, and a cathode current collector. The space between the ion exchange membrane and the anode current collector forms a first channel and the space between the ion exchange membrane and the cathode current collector forms a second channel. The ion exchange membrane is configured to allow ions to pass between the first and second channel. The battery includes a first tank configured to flow an anolyte through the first channel, wherein the anolyte is hydrogen gas. The battery includes a second tank configured to flow a catholyte through the second channel, wherein the catholyte is a compound that can be reversibly hydrogenated and dehydrogenated. The flow cell battery can be used to generate electric current.

A carrier-nanoparticle complex, a catalyst including the same, an electrochemical cell including the catalyst, and a method for preparing a carrier-nanoparticle complex.

Control of supplying power to a storage device is performed based on carbon emission strength or a power rate. A battery center 13 that constitutes a storage device 11 performs radio communication with a gateway 4 and is controlled by the gateway 4. The gateway 4 collects a measured value of power consumed by electric appliances in a home and obtains the carbon emission strength in real time. A solar panel 9 is provided and a battery of the storage device 11 is charged with an output of the solar panel. The battery is also charged with direct current power obtained from power from outside. The power is stored in the storage device 11 based on the carbon emission strength by charging control.

Control of supplying power to a storage device is performed based on carbon emission strength or a power rate. A battery center 13 that constitutes a storage device 11 performs radio communication with a gateway 4 and is controlled by the gateway 4. The gateway 4 collects a measured value of power consumed by electric appliances in a home and obtains the carbon emission strength in real time. A solar panel 9 is provided and a battery of the storage device 11 is charged with an output of the solar panel. The battery is also charged with direct current power obtained from power from outside. The power is stored in the storage device 11 based on the carbon emission strength by charging control.

Electrochemical cells, such as those present within flow batteries, can have at least one electrode with a density gradient in which the density increases outwardly from a separator. Such electrodes can decrease contact resistance and lessen the incidence of parasitic reactions in the electrochemical cell. Flow batteries containing the electrochemical cells can include: a first half-cell containing a first electrode, a second half-cell containing a second electrode, and a separator disposed between the first half-cell and the second half-cell. At least one of the first electrode and the second electrode has a density gradient such that a density of at least one of the first electrode and the second electrode increases outwardly from the separator.

Electrochemical cells, such as those present within flow batteries, can have at least one electrode with a density gradient in which the density increases outwardly from a separator. Such electrodes can decrease contact resistance and lessen the incidence of parasitic reactions in the electrochemical cell. Flow batteries containing the electrochemical cells can include: a first half-cell containing a first electrode, a second half-cell containing a second electrode, and a separator disposed between the first half-cell and the second half-cell. At least one of the first electrode and the second electrode has a density gradient such that a density of at least one of the first electrode and the second electrode increases outwardly from the separator.