Abstract: A novel cathode of low hydrogen overvoltage is provided which is useful for electrolysis of water and electrolysis of an aqueous alkali metal chloride such as sodium chloride. A process for producing the cathode is also provided. The low hydrogen overvoltage cathode comprises an electroconductive base material; and a coating layer containing at least one organic compound selected from the group consisting of amino acids, monocarboxylic acids, dicarboxylic acids, monoamines, diamines, triamines, and tetramines, and derivatives thereof at a content of from 0.5% to 18% by weight in terms of carbon, and a metal component selected from the group consisting of nickel, nickel-iron, nickel-cobalt, and nickel-indium at an indium content ranging from 1% to 90% by weight.

Abstract: A process for synthesizing iron(III) hexacyanoferrate(II) as a blue insoluble product on the surface of a working electrode is disclosed which comprises immersing a pair of electrodes in a solution mixture of an iron(III) ion-containing solution and a hexacyanoferrate(III) ion-containing solution and effecting electrolysis with one of the electrodes as an anode and the other as a cathode, whereby iron(III) hexacyanoferrate(II) is deposited on the surface of the cathode.

Abstract: A high capacity long cycle life positive electrode which includes an electronically conductive substrate for conducting electricity through the electrode and an electrochemically active nickel hydroxide material in electrical contact with the electronically conductive substrate, the electrochemically active nickel hydroxide material is composed of at least two different solid solution nickel hydroxide materials each having differing compositions. The positioning of the at least two different solid solution nickel hydroxide materials and their relative compositions alter the local redox potential or porosity to force discharge of the electrode in a stepwise fashion from the nickel hydroxide material remote from said conductive network or substrate, through any intermediate nickel hydroxide materials, to the nickel hydroxide material adjacent the conductive network or substrate.

Abstract: The present invention is an electrodeposited copper foil characterised in that roughening treatment is performed on a matte side of an untreated copper foil wherein the surface roughness R.sub.z of the matte side of the untreated copper foil is the same as or less than the surface roughness R.sub.z of the shiny side of this untreated copper foil. The electrodeposited copper foil is made by electrodepositing copper onto a drum from an electrolyte which contains 0.05 to 5 ppm 3-mercapto 1-propanesulfonate; at least one organic compound selected from 0.1 to 15 ppm of a polysaccharide which is a carbohydrate such as starches, celluloses and vegetable rubbers, and 0.3 to 35 ppm of a low molecular weight glue having a weight average molecular weight of 10,000 or less; and 10 to 60 ppm of a chloride ion. The copper foil may be used in making a printed circuit board or as a component of a secondary battery cell.

Abstract: There is provided manganese dioxide to be suitably used for alkaline manganese batteries and manganese batteries to make them excellent both in the initial performance and the storability. There is also provided a method of manufacturing such manganese dioxide. The electrolytic manganese dioxide has a BET specific surface area of less than 30 m.sup.2 /g (preferably less than 27 m.sup.2 /g) and a suspensiveness of less than 50 mg/liter. A method of manufacturing electrolytic manganese dioxide may be a suspension method, wherein manganese oxide is suspended at a rate of 0.01 to 0.2 g/liter in an electrolytic bath containing sulfuric acid at a concentration of 0.4 to 0.55 mol/liter and electrolyzed to produce electrolytic manganese dioxide with an anodic current density of 0.4 to 3.0 A/dm.sup.2 and an electrolytic temperature of 93.degree. to 103.degree. C., the relationship between the anodic current density and the electrolytic temperature being expressed by 103.gtoreq.y.gtoreq.1.67x+92.

Abstract: An electrolytic cell, such as a rechargeable lithium battery, having cavitands associated with a metal ion source-electrode and an electrolyte. The cavitands, which are anchored to the electrode by a polymer leash, are capable of releasably attracting particular ions, such as lithium ions, which are migrating from the electrolyte, toward the surface of the electrode during electrodeposition. The polymer leash serves to continuously maintain the cavitands at a predetermined distance away from the surface of the electrode, regardless of surface area fluctuations, typically caused during deposition and dissolution of the particular ions. Accordingly, the cavitands facilitate substantially uniform electrodeposition of the particular ions, which, in turn, substantially suppresses and/or controls the formation and growth of a passive film or layer, on the electrode surface, which may otherwise promote the formation of dendrites.

Abstract: A method of making a cathode for a high temperature rechargeable electrochemical cell comprises impregnating a mixture, in granular form, of an alkali metal halide and a substance comprising a transition metal selected from the group consisting of iron, nickel, cobalt, chromium, manganese, and mixtures thereof, with an alkali metal aluminium halide molten salt electrolyte. The impregnated mixture is subjected to at least one charge cycle in a high temperature electrochemical cell in which the impregnated mixture forms the cathode and is located in a cathode compartment of the cell. The cathode compartment is separated from an anode compartment by a solid electrolyte separator. Alkali metal forms in the anode compartment during the charge cycle.

Abstract: Method for the manufacture of a photoelectrochemical cell and a cell made by this method. A disadvantage of such cells (1) is the fact that their efficiency is not sufficient for economic use. It is therefore the aim of the invention to avoid this disadvantage. The method according to the invention makes it possible to produce a photoelectrochemical cell (1) comprising a porous electrode (4), the effective surface of which is by a factor 700 greater than that of electrodes of comparable size.

Abstract: A high temperature rechargeable electrochemical power storage cell has an anode compartment and a cathode compartment separated from each other by a separator. The cathode compartment contains a current collector; an alkali metal aluminium halide molten salt electrolyte having the formula MAlHal.sub.4 ; an alkali metal halide; and a cathode. The cathode comprises an electrolyte-permeable porous matrix, a first active cathode substance in the matrix in a first zone adjacent the current collector and spaced from the separator, and a second active cathode substance in the matrix in a further zone adjacent the first zone. The first active cathode substance is such that it gives rise to a higher cell potential than does the second active cathode substance. The cell is chargeable at a temperature at which the electrolyte and the alkali metal are molten to cause the active cathode substances to be halogenated.

Abstract: An electrochemical cell comprising a body of proton donor electrolyte in effective contact with first and second electrodes one of which consists essentially of a fullerene in contact with a conductive material. By the application of an electric current across the electrodes the cell can be used to hydrogenate the fullerene, thereby storing hydrogen and electric energy.

Abstract: The present invention provides a lithium battery comprising a cathode active material having as its major component amorphous V.sub.2 O.sub.5. The amorphous V.sub.2 O.sub.5 is prepared by electrochemically reacting crystalline vanadium pentoxide (V.sub.2 O.sub.5) with lithium in a cell to a voltage sufficient to transform crystalline vanadium pentoxide to amorphous vanadium pentoxide. Preferably, the electrochemical reaction is conducted in a V.sub.2 O.sub.5 --Li cell of about 1.5 V at a relatively constant current in a range of about 0.05 milliamps per cm.sup.2 to about 0.5 milliamps per cm.sup.2.

Abstract: An electrode for a rechargeable electrochemical cell including an electrically conductive substrate, a layer of an electrochemically active material attached to the substrate, the active material comprising a reducible species of a metal, at least one conductive contact area formed of a metallic form of said metal attached to said substrate, said metallic contact area comprising said reducible species in a converted form. A positive electrode is further provided wherein said active material is nickel hydroxide and said metallic form of said metal is nickel metal. The invention further comprises the method for manufacturing electrodes as described above, featuring use of reducing gas to effect conversion.

Abstract: A method for producing a metallic oxide-hydrogen secondary battery is provided. The method comprises the steps of disposing generating elements consisting of positive electrodes containing metallic oxides, negative electrodes containing hydrogen-absorbing alloys, and separators in a plurality of cell chambers equipped with safety valves, each cell chamber having different capacity; pouring an electrolyte into each cell chamber; and repeating charge and discharge cycles on condition that safety valves work at pressure G in the range of 1<G.ltoreq.6 atm so that the amount of the electrolyte in each cell chamber is kept constant.

Abstract: A method for making a battery electrode includes roughening the surface of a substrate (10) that constitutes a precursor to the electrode, using an electrolytic solution (12) with electrical potential perturbations applied thereto. The substrate (10) of porous sintered nickel powder is first formed. The electrolytic solution (12) prefereably contains the pure metal that forms the electrode. Then all gases in and around the substrate (10) are preferably removed. Next, the substrate (10) is placed in the solution (12) for a predetermined amount of time. Potential perturbations are then applied to the substrate (10) and the solution (12). The potential peturbations vary between the voltages necessary for electrodissolution and electrodepositon of the substrate (10), and thus, cause the surface of the substrate (10) to be roughened as portions of the substrate (10) are dissolved into the solution (12) and then redeposited onto the substrate's (10) surface.

Abstract: A method of manufacturing manganese dioxide containing 0.05 to 2.0 parts by weight of phosphorus which consists of introducing a manganese sulfate solution and sulfuric acid as an electrolyte into an electrolytic cell, adding to said electrolyte at least one member selected from the group consisting of phosphoric acid, phosphorous acid, hypophosphorous acid and compounds thereof and carrying out the electrolysis at a bath temperature of 92.degree. to 100.degree. C. whereby manganese dioxide containing phosphorus is electrodeposited on the cathode.

Abstract: Cells are disclosed using doped electroconductive polymer electrodes and electrolytes of alkali metal cations and soft anions in polar organic solvents. The structure of the negative electrodes comprises layers of electroconductive polymers and ion exchange resin. Conditioning the negative electrodes is effected with AC current, the energy of the negative pulses exceeding that of the positive pulses.