Abstract: A novel, improved battery separator and process for making the separator. Essentially, the separator carries a plurality of polymeric ribs bonded to at least one surface and the ribs have alternating elevated segments of uniform maxiumum heights and depressed segments along the length of the ribs.

Abstract: A composition suitable for use as a battery separator comprising a substantially homogeneous mixture of a copolymer of ethylene and acrylic acid having from 10 to 23 mole percent acrylic acid therein and a melt index of from about 0.1 to 5 in combination with a copolymer of ethylene and acrylic acid having at least 25 mole percent acrylic acid therein and having a melt index of at least about 10. The present invention is further directed to a process of forming a sheet product from the subject composition and the use of the formed product as a battery separator.

Abstract: A method for manufacturing tubular shaped thermoplastic members comprising conveying two thin sheets of thermoplastic material in close substantially parallel relationship through an ultrasonic welding station for forming a plurality of continuous spaced apart seams substantially parallel to the direction of conveying for joining the two sheets of thermoplastic material. The seams, thus formed, are cut substantially parallel to the direction of conveying such that the two sheets of thermoplastic material remain joined adjacent each side of the cuts. Preferably, the cutting takes place substantially simultaneously with the ultrasonic formation of the seams and the thin sheets of thermoplastic material are cooled prior to the ultrasonic welding. An apparatus for practicing the method is also disclosed. The method and apparatus are particularly adaptable for the manufacture of ionically permeable thermoplastic separators for use in electrochemical cells and the like.

Abstract: An improved electrode coating and separator coating derived from a copolymer of diacetone acrylamide and a polymerizable monomer.

Abstract: A battery separator having a low electrical resistance after extended use is made by thermal consolidation and thermal embossing of a paper web formed from a furnish containing a synthetic pulp the fibrils of which are filled with an inorganic filler, the web incorporating a wetting agent which is preferably an organic sulphonate, and organic succinate, or a phenol ethoxylate.

Abstract: A fluid transmitting polyolefin foam having a special open-cell cellular structure as compared with the conventional polyolefin foams having all cells closed is disclosed. Such a novel fluid transmitting polyolefin foam is produced by mixing a polyolefin with a polymer other than a polyolefin, said polyolefin and/or said polymer other than a polyolefin having a blowing agent incorporated therein and/or adhered thereto and subjecting the resulting mixture to extrusion moulding. The present fluid transmitting polyolefin foam has a wide variety of uses, for example, as a synthetic leather, synthetic filter cloth, separator of storage battery, synthetic paper, package, etc.

Abstract: A separator for an electrochemical cell comprising a container having opposing sides each formed from a layer of solid microporous material and a liquid polymer solution disposed within the container between said layers.

Abstract: An improved electrode coating and separator coating derived from a copolymer of diacetone acrylamide and a polymerizable monomer.

Abstract: Electrochemical power cells having a cathode current collector, a combination liquid active cathode depolarizer electrolyte solvent and an anode that forms surface compounds when in intimate contact with the liquid cathode are enhanced by the addition of a passivation limiting film contiguous to said anode. The passivating film is a member of the cyanoacrilate family of organic compounds.

Abstract: A method is provided for sealing portions of cation exchange membranes of carboxylic acid type fluorinated polymers. The portions of the membranes to be sealed are in the ester form of the membrane and are ultrasonically sealed at sealing times of from about 0.1 to about 5 seconds while employing power in the range of from about 50 to about 600 watts.The novel method of the present invention can be used to repair membranes of carboxylic acid type fluorinated polymers which have been torn, slit, or cut. Sections of membrane materials may be sealed together to form an enlarged or reinforced membrane. The sealed portions are substantially free of wrinkles and are not mechanically damaged or weakened.

Abstract: A method of producing a dimensionally stable battery separator characterized by grafting acrylic acid and/or methacrylic acid onto a polyethylene film, treating the resulting membrane with an aqueous alkaline solution, and drying the treated membrane under application of tension.

Abstract: A galvanic cell separator composed of polyvinyl alcohol having a crystallinity of 0.4 or more to be used with a galvanic cell containing alkaline electrolyte, and a method of manufacturing the same.

Abstract: A film-forming polyvinyl alcohol polymer is mixed with a polyaldehyde-polysaccharide cross-linking agent having at least two monosaccharide units and a plurality of aldehyde groups per molecule, preferably an average of at least one aldehyde group per monosaccharide units. The cross-linking agent, such as a polydialdehyde starch, is used in an amount of about 2.5 to 20% of the theoretical amount required to cross-link all of the available hydroxyl groups of the polyvinyl alcohol polymer. Reaction between the polymer and cross-linking agent is effected in aqueous acidic solution to produce the cross-linked polymer. The polymer product has low electrical resistivity and other properties rendering it suitable for making separators for alkaline batteries. In that event, the mixture of polymer and cross-linking agent is formed into a sheet or film or the like and the film is cut to size and otherwise fabricated into a configuration suitable for a particular end use.

Abstract: A method of producing a cross-linked polyvinyl alcohol structure, such as a battery separator membrane or electrode envelope. An aqueous solution of a film-forming polyvinyl alcohol is admixed with an aldehyde cross-linking agent at basic pH to inhibit cross-linking. The cross-linking agent, preferably a dialdehyde such as glutaraldehyde, is used in an amount of from about 1/2 to about 20% of the theoretical amount required to cross-link all of the hydroxyl groups of the polymer. The aqueous admixture is formed into a desired physical shape, such as by casting a sheet of the solution. The sheet is then dried to form a self-supporting film. Cross-linking is then effected by immersing the film in aqueous acid solution. The resultant product has excellent properties for use as a battery separator, including a low electrical resistivity, the value of which is principally determined by the amount of cross-linking which is easily and closely controlled by the amount of cross-linking agent added to the polymer.

Abstract: Provided is dried porous membrane composed of acrylonitrile polymer walls separating predominantly interconnecting small-size pores. The membrane has surface layers integrated with a support layer to form a single continuous acrylonitrile polymer phase. At least one of the surface layers has pores of from 0.001 to 0.05 micron in average size, and the support layer has pores which are on the average larger than the pores in the surface layer or layers. The membrane has a porosity of from 20% to 70% by volume and a fragility of below 30. The membrane exhibits improved mechanical properties.

Abstract: An improved method for manufacturing membrane battery separators by grafting a vinyl monomer onto a polyolefin film. The method includes irradiation of the film by ultraviolet rays and subsequent grafting of the said film in a five-layer sandwich. The sandwich comprises the irradiated polyolefin film which is covered on each side with a layer of a cellulosic tissue soaked with the monomer or a solution of the monomer, and each cellulosic layer on its turn is covered by an inert polymeric film. The layers of the sandwich are not limited in length and the sandwich is transported at a constant speed over the surface of a heater, maintaining the sandwich at a constant temperature in the range 85.degree. to 95.degree. C. with an accuracy of .+-.1.degree. C. The grafting of the polyolefin film in the sandwich proceeds continuously and isothermally, while it is in contact with the heater surface under a pressure of 10 to 30 g/cm.sup.2 during 10 to 45 minutes.

Abstract: Fragmentation with electrical discontinuity in a consumable electrode of an electrochemical cell is minimized by preventing a portion of said electrode from reacting by means of a reaction barrier.

Abstract: An alkaline primary cell comprising a positive electrode having an upper layer, facing the negative electrode, of electrolytic .gamma.-manganese dioxide to which 6-16% of graphite powder having a broad grain-size range has been added as a conducting additive. Disposed beneath this upper layer is at least one further layer containing .gamma.-manganese dioxide, mercuric oxide, or monovalent silver oxide having a higher apparent specific gravity than the upper layer. A separator comprising at least one membrane layer is situated above the positive electrode.

Abstract: The invention relates to a semi-permeable membrane for lead-acid batteries. The membrane has a microporous structure comprising a first polymer and a second polymer closely mixed together, the first polymer being poly (2-hydroxyethylmethacrylate), known as reticulated poly HEMA, characterized by the fact that the second polymer comprises one polymer or a mixture of several different polymers chosen from among polyoxyethylene glycol, polyvinylpyrrolidone, polyacrylic acid, polymethacrylic acid, copolymers of acrylic and methacrylic acid, polyacrylates and polymethacrylates of alkyl, and the copolymers of the acrylates and methacrylates of alkyls.

Abstract: A battery containing an alkaline electrolyte, having within a container, said electrolyte and two electrodes separated by a separator; said separator being made of a partially reticulated polyvinyl acetal produced by the action of at least one aldehyde on polyvinyl alcohol; preferably an aromatic aldehyde, which may also have at least one hydroxyl radical, being used together with formaldehyde.

Abstract: A galvanic cell comprising at least one rechargeable zinc electrode as anode, at least one other electrode as cathode, an electrolyte, and at least one foraminous electrically conductive auxiliary structure interposed between every anode and cathode. The auxiliary structure is galvanically separated from the electrodes of the cell and macroscopically visible electrolyte zinc deposition from the cell electrolyte thereon is only observed at potentials which are more negative than on a smooth nickel structure.

Abstract: The invention relates to a semi-permeable membrane for lead acid batteries. The membrane has a microporous structure comprising a first polymer and a second polymer closely mixed together, the first polymer being poly (2-hydroxyethylmethacrylate), known as reticulated poly HEMA, characterized by the fact that the second polymer comprises one polymer or a mixture of several different polymers chosen from among polyoxyethylene glycol, polyvinylpyrrolidone, polyacrylic acid, polymethacrylic acid, copolymers of acrylic and methacrylic acid, polyacrylates and polymethacrylates of alkyl, and the copolymers of the acrylates and methacrylates of alkyls.

Abstract: The invention relates to a semi-permeable membrane for a lead-acid battery. The membrane has a microporous structure comprising a first polymer and a second polymer intimately mixed together, and is characterized by the fact that the first polymer is chosen from among the following polymers: polyacrylic acid, polymethacrylic acid, a copolymer with a high proportion of acrylic or methacrylic acid, a mixture of these polymers, the average molecular weight of these polymers lying between 10,000 and a few millions and preferably between 50,000 and one million, the second polymer being soluble in water.

Abstract: A battery containing an alkaline electrolyte, having within a container, said electrolyte and two electrodes separated by a separator; said separator being made of a partially reticulated polyvinyl acetal produced by the action of at least one aldehyde on polyvinyl alcohol; preferably an aromatic aldehyde, which may also have at least one hydroxyl radical, being used together with formaldehyde.

Abstract: Production of inorganic porous sintered battery separator substantially eliminating formation of gas when in contact with a zinc electrode, and permitting long cycle life of a high energy density battery such as a silver-zinc battery, produced according to one embodiment by initially firing a mixture of magnesium-bearing material, e.g., MgO, zinc-bearing material, e.g., ZnO, and silica (SiO.sub.2), at temperature in the range of about 1,100 to about 1,500.degree. C, to produce a magnesium silicate-zinc silicate composition, granulating and compacting said composition into plaques, and sintering said compacted plaques at temperature ranging from about 1,000.degree. to about 1,300.degree. C, to produce porous sintered separator members, in the form of a sintered solid solution of magnesium silicate and zinc silicate, having good transverse strength and low resistivity.

Abstract: A rechargeable aqueous metal-halogen cell is described which includes a casing, a pair of spaced apart porous electrode substrates in the casing, a micro-porous separator between the electrode substrates defining a positive and a negative electrode compartment, an aqueous electrolytic solution containing a zinc salt selected from the class consisting of zinc bromide, zinc iodide, and mixtures thereof in both compartments, and an organic halogen complexing additive of nitrobenzene in the electrolytic solution of at least the positive compartment.

Abstract: A bipolar, lead acid battery incorporating titanium and/or zirconium electrode supports and having a fibre filling to maintain a pressure on the active mass located on the supports.

Abstract: A battery separator comprising a microporous sheet formed substantially of a mixture of polymeric constituents. One of the polymeric constituents is an ultra high molecular weight polyolefin having a standard load melt index of substantially 0 and an intrinsic viscosity greater than about 3.0. The other polymeric constituent is either a copolymer of an olefin and an ethylenically unsaturated monocarboxylic acid selected from the group consisting of acrylic acid and methacrylic acid, or a blend of a low molecular weight polyolefin and a polymer of acrylic or methacrylic acid.

Abstract: An improved electrical conversion device of the type comprising: (1) an anodic reaction zone containing a molten alkali metal reactant-anode in electrical contact with an external circuit; (2) a cathodic reaction zone containing a cathodic reactant comprising a liquid electrolyte which is electrochemically reactive with said anodic reactant and an electrode of porous conductive material which is at least partially immersed in said cathodic reactant; and (3) a cation-permeable barrier to mass liquid transfer interposed between and in contact with said anodic and cathodic reaction zones, said porous conductive material being in electrical contact with both said cation-permeable barrier and an external circuit; the improvement of the invention comprising a modification of the cathodic reaction zone of the device such that there are a plurality of channels and/or spaces within the zone which are free of the porous conductive material and which in combination with said porous conductive material are adapted to all