An electrolyte-circulating battery according to the present invention includes a cell frame including a bipolar plate in contact with an electrode that forms a battery cell, and a frame that surrounds a peripheral edge of the bipolar plate; and a sealing member that is disposed on the frame and that prevents an electrolyte supplied to the battery cell from leaking out of the frame. The frame has a seal groove in which the sealing member is fitted. The seal groove includes a narrow section that causes the sealing member to elastically deform to prevent the sealing member from becoming detached from the seal groove. The narrow section has a width that is uniform in a depth direction of the seal groove.

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 method is disclosed of manufacturing a semiconductor structure comprising an (001) oriented zincblende structure group III-nitride layer, such as GaN. The layer is formed on a 3C-SiC layer on a silicon substrate. A nucleation layer is formed, recrystallized and then the zincblende structure group III-nitride layer is formed by MOVPE at temperature T3 in the range 750-1000° C., to a thickness of at least 0.5μ. There is also disclosed a corresponding semiconductor structure comprising a zincblende structure group III-nitride layer which, when characterized by XRD, shows that the substantial majority, or all, of the layer is formed of zincblende structure group III-nitride in preference to wurtzite structure group III-nitride.

The present invention provides methods for producing hydrogen using a mediator that is capable of reversibly donating and accepting four or more electrons. A method of the invention comprises the steps of reducing a mediator by four or more electrons to yield a reduced mediator, and oxidising a reduced mediator to yield a mediator, and reducing protons to yield hydrogen.

A solid ionic conducting material for use in an electrochemical device comprises an oxyhydroxide or hydrated oxide derived from of an oxide with a perovskite, Brownmillerite, layered oxide, and/or K.sub.4CdCl.sub.6 structure, the elemental composition of the initial oxide being selected to provide suitable conduction properties for the derived anhydrous or hydrated oxyhydroxide or hydrated oxide. A method of making such a solid ionic conducting material, including treatment with water, and an electrochemical device incorporating such a solid ionic conducting material (optionally as an electrolyte) are also disclosed.

The present invention relates to a zinc/aqueous polysulfide rechargeable flow battery (100) made of a first half-cell (110) comprising a first electrolyte (114) containing a source of Zn.sup.2+ ions and a static (112) or flowable electrode disposed within the first half-cell, said first half-cell being connected in a closed-loop configuration through a first pump (116) to a first external tank (115) containing the first electrolyte; a second half-cell (120) comprising a second electrolyte (124) in which polysulfides are dissolved and a static (122) or flowable electrode disposed within the second half-cell, said second half-cell being connected in a closed-loop configuration through a second pump (126) to a second external tank (125) containing the second electrolyte; and a catalyst in the second half-cell, on the surface of a static electrode or dispersed in form of particles in the second electrolyte; and a separator (130) between the two half-cells.

The rechargeable flow battery of the invention avoids the use of toxic or environmentally harmful chemicals.

A redox-flow battery includes a cell arrangement and a tank device for holding electrolyte. The battery includes a measuring device for determining an open circuit voltage and a circulating module, and the measuring device for determining an open circuit voltage includes at least one measuring cell and at least four connections. One connection is provided for the supply of anolyte, one connection for the removal of anolyte, one connection for the supply of catholyte, and one connection for the removal of catholyte. The circulating module includes at least one pump head and at least two pump impellers, and the at least one measuring cell is integrated into the pump head. A connection of the measuring device is connected to a pressure side of a pump impeller, and the associated connecting line is integrated in the pump head.

The redox flow secondary battery includes an electrolytic cell including a positive electrode cell, a negative electrode cell, and a separation membrane that separates the positive electrode cell and the negative electrode cell. Moreover, the above described redox flow secondary battery is configured as follows. That is, the separation membrane has a microporous membrane and an ion-exchange resin layer contacting the microporous membrane, and the air resistance of the separation membrane per thickness of 200 μm is 10000 sec/100 cc or more. Furthermore, the microporous membrane includes a polyolefin resin or a vinylidene fluoride resin and an inorganic filler. Further, the smoothness of at least a surface of the microporous membrane contacting the ion-exchange resin layer is 16000 seconds or less.

Active materials for flow batteries can include various coordination compounds formed from transition metals. Some compositions containing coordination compounds can include a substituted catecholate ligand having a structure of ##STR00001##
in a neutral form or a salt form, in which Z is a heteroatom functional group bound to the substituted catecholate ligand at an open aromatic ring position and n is an integer ranging between 1 and 4. When more than one Z is present, each Z can be the same or different. Electrolyte solutions can include such coordination compounds, and such electrolyte solutions can be incorporated within a flow battery.

Various current collectors for redox flow batteries are described. The current collectors include at least one metal plate encapsulated in a conductive polymer end plate, the metal plate to the back of a stack end plate with a conductive adhesive, and a flat metal plate having deformable tabs. Battery flow systems incorporating the current collectors are also described. Battery flow systems with easily replaceable current collectors are also described.

The present disclosure relates to a composition that includes a first layer that includes a polymer having a repeat unit with a structure that includes

##STR00001##

where m is between 2 and 100, inclusively, the repeat unit is protonated at at least one of position A) and/or B) and/or sulfonated at at least one of rings 1) and/or 2), R.sub.1 includes at least one of a lone pair of electrons, a covalent bond, hydrogen, and/or a hydrocarbon functional group, R.sub.2 includes at least one of a lone pair of electrons, a covalent bond, hydrogen, and/or a hydrocarbon functional group, and is a covalent bond.