Patents Assigned to Varta Batterie Aktiengesellschaft
  • Patent number: 5141827
    Abstract: An ion conductor/electrolyte especially suitable for lithium batteries is comprised of a chemically inert, electronically nonconducting solid powder and an electrolyte salt solution with an aprotic solvent. The ion conductor has a solid to pasty consistency depending upon the ratio of the mixture's components and has a specific conductivity (.kappa.) of a magnitude >10.sup.-3 S/cm at room temperature. Using this ion conductor, solid batteries can be developed with output capacities similar to those previously available only in connection with liquid organic electrolyte systems. Among others, SiO.sub.2, Al.sub.2 O.sub.3 and TiO.sub.2 are favorable solids as carriers, especially with extensive surface areas. The liquid phase, which is immobilized by adsorption on these carriers, is formed of a solution of lithium or sodium salts in propylene carbonate, acetonitrile, gamma-butyrolactone, nitromethane, tetrahydrofuran and dimethoxyethane, or similar solvents.
    Type: Grant
    Filed: August 20, 1990
    Date of Patent: August 25, 1992
    Assignee: Varta Batterie Aktiengesellschaft
    Inventors: Heinz P. Fritz, Klaus Stein
  • Patent number: 5128219
    Abstract: In a metal oxide/hydrogen storage battery, preferably formed as a coiled cell or as a button cell, having a negative electrode, a positive electrode, and an intermediate separator, the oxidation-sensitive negative electrode is protected against diffusing oxygen by a metallic covering of the electrode's metal hydride particles, and the oxygen reduction necessary for gas-tight operation is transferred to an auxiliary electrode which is arranged outside of the ionic path between the positive and negative electrodes. Metals with high solubility for hydrogen, such as Pd, Ni and Cu, are suitable as the covering material. The auxiliary electrode is formed as a film based on a mixture of activated carbon, a PTFE binder and conducting graphite, and is either laminated onto the negative metal hydride electrode or is spatially separated from the main electrodes, depending upon the cell's overall construction.
    Type: Grant
    Filed: August 17, 1990
    Date of Patent: July 7, 1992
    Assignee: Varta Batterie Aktiengesellschaft
    Inventors: Uwe Kohler, Gerhard Simon, Gunter Hofmann
  • Patent number: 5122426
    Abstract: An auxiliary electrode for improving the consumption of oxygen in a gas-tight, sealed alkaline secondary cell is comprised of a synthetic nonwoven fabric and a film rolled onto the fabric. The film is a PTFE-bound activated carbon, and the side of the nonwoven fabric receiving the film is first impregnated with an aqueous cellulose ether mixture to develop a three layer structure including a highly porous, hydrophobic layer made of the nonwoven material, left in its original state and facing the electrolyte or a gas supply, a hydrophilic impregnated layer, and a catalytically active hydrophobic consumption layer electrically connected with the cell's negative electrode and constituting the preferred location for oxygen reduction, at the resulting hydrophobic/hydrophilic transition layer.
    Type: Grant
    Filed: August 17, 1990
    Date of Patent: June 16, 1992
    Assignee: Varta Batterie Aktiengesellschaft
    Inventors: Gerhard Simon, Klaus Kleinsorgen, Uwe Kohler
  • Patent number: 5108668
    Abstract: In connection with a device for casting lead grids for electric battery plates, a highly porous ceramic mold lining, preferably of zirconium oxide, is prepared by flame-spraying. Such a lining can include a thin surface coating on a profiled, basic metallic mold or a separately prepared insert plate which is retained to a metallic mold molder. The ceramic surface coating may be accurately formed in place, or may be formed as an over-spray which is then reduced in thickess. Formation of the surface coating may be accomplished by placing masks on the basic metallic mold during the flame spraying, for those areas of the grid which tend to accumulate material, or by adjusting an initially coarse profile of the ceramic layer to the exact profile of the casting by a material-removing treatment.
    Type: Grant
    Filed: August 12, 1986
    Date of Patent: April 28, 1992
    Assignee: Varta Batterie Aktiengesellschaft
    Inventor: Bernhard E. Kallup
  • Patent number: 5049162
    Abstract: A plastic sealing element for dry cells includes a radially symmetrical, contrally perforated base element, the upper side of which is provided with an elastomeric sealing material which is extruded in the form of a circumferential annular bead, and a process for its manufacture. After the sealing element is pre-assembled with the cell's metal housing cover and the cell is assembled, the annular bead is pressed flat during final crimping so that a sealing zone having a small cross section and defining a long leakage path is developed between the cover and the base element, effectively preventing the leakage of electrolyte or water vapor, which is especially diffuse from the cell's porous carbon rod conductor, into the cell's sealing zone.
    Type: Grant
    Filed: May 23, 1990
    Date of Patent: September 17, 1991
    Assignee: Varta Batterie Aktiengesellschaft
    Inventors: Klaus Ruggeberg, Horst-Udo Jose
  • Patent number: 5047302
    Abstract: An aluminum substrate, with its natural oxide film intact, is made suitable for the electrochemical deposition polymerization of the electrode-active organic material, and for further use as an electrolyte holder and a charge eliminator, by providing the aluminum substrate with an electron-conducting coating of Au, Pt, Ni, Cr, Cr-Ni or C. In blank form, following pickling in an alkali, the aluminum substrate can either directly receive the deposit, or can be prepared for this purpose by electrochemical coating with a corrosion-resistant heavy metal.The aluminum can be used in the form of a netting or expanded metal so as to achieve a particularly firm connection between the metal and the polymer, and so that the resulting mesh cavities can be used to incorporate the amount of electrolyte which is necessary for charging of the polymer electrode. This allows the use of a thinner separator as the electrolyte reservoir, improving the power density of the cell.
    Type: Grant
    Filed: August 10, 1987
    Date of Patent: September 10, 1991
    Assignee: Varta Batterie Aktiengesellschaft
    Inventors: Rainer Bittihn, Friedrich Woeffler, Georg Ely
  • Patent number: 5043235
    Abstract: A galvanic battery having band-shaped positive and negative electrodes, and an intermediate band-shaped separator, which are helically wound to develop an electrode structure for mounting within a cylindrical housing having a cell pole sealed and insulated against the housing, includes a connecting element which electrically bridges the gap between the cell pole and the edge of the corresponding electrode band and which is comprised of a contact plate having a branched contact clamp concentrically welded to it, an insulation plate positioned over the contact plate and having a centrally disposed aperture for receiving the branched contact clamp, and a pressure spring placed over the insulation plate so that the contact plate presses on the exposed edge of the corresponding electrode band under the influence of the pressure spring, and so that the cell pole is received within the branched contact clamp.
    Type: Grant
    Filed: June 28, 1990
    Date of Patent: August 27, 1991
    Assignee: Varta Batterie Aktiengesellschaft
    Inventors: Volker Seefeldt, Thomas Apprich
  • Patent number: 5021306
    Abstract: A spiral-wound galvanic cell is based upon a lithium system with a nonaqueous electrolyte, and includes a positive electrode, the carrier of which is clamped within the slit of a simple metal splint which serves as the winding mandrel and current collector. Contact with the metal splint is established by a leaf spring associated with the housing cover, which then serves as the positive terminal post for the cell. A high specific contact pressure is developed at this connection by providing the leaf spring with a punched hole which rests on thicker top portions of the metal splint. A small metal plate pressed through the lithium electrode and its separator establishes electrical contact between the lithium electrode and the interior wall of the housing vessel, which then serves as the negative cell pole.
    Type: Grant
    Filed: November 15, 1989
    Date of Patent: June 4, 1991
    Assignee: Varta Batterie Aktiengesellschaft
    Inventors: Hans Sauer, Peter Kramer
  • Patent number: 4994333
    Abstract: In an acid-type primary cell with a zinc anode containing non-toxic or only little harmful substances, the usual toxic components of the zinc alloy such as mercury and cadmium are replaced by at least one of the elements indium and bismuth, and by at least one of the elements magnesium and lithium. These nonpoisonous substitutes inhibit hydrogen on the zinc and provide a degree of mechanical tensile strength with more conventional zinc anodes. Additionally, a slight amount of lead is alloyed with the zinc anode to maintain ductility during the rolling process and as a supplemental protection against corrosion.
    Type: Grant
    Filed: November 15, 1989
    Date of Patent: February 19, 1991
    Assignee: Varta Batterie Aktiengesellschaft
    Inventors: Horst-Udo Jose, Gerd Jung
  • Patent number: 4987041
    Abstract: Overcharge protection, and especially the chargeability of a sealed Ni/Cd battery with high currents (up to 1 CA) is improved by rolling a carbon-containing powdered material into the surface of the negative electrode, which material catalyzes the reduction of oxygen. Wetting of the electrode with a "Tylose" dispersion prior to application of the powder (by powdering, vibration or in an agitator) improves the adhesion of the powder. The cadmium electrode thus prepared combines in itself the functions of a negative principal electrode and of an auxiliary oxygen electrode.
    Type: Grant
    Filed: December 21, 1989
    Date of Patent: January 22, 1991
    Assignee: Varta Batterie Aktiengesellschaft
    Inventor: Gerhard Simon
  • Patent number: 4965105
    Abstract: An insulation sleeve for the can-shaped soluble anode of a round galvanic primary cell, which immobilizes emerging electrolyte and shields retained moisture from the exterior, and which electrically insulates the electrode conductor, includes a helically wound paper web having a plastic lining on one side and a lengthwise paper edge which is endlessly folded over, and which is wound onto a winding spindle so that the folded-over edge helically overlaps the opposite edge of the paper web to allow the superimposed plastic layers to be welded to one another in the overlapping zone. By successively winding a conventional paper strip with the plastic-lined paper web, an even stronger sleeve tube is obtained, which can then be cut into individual sleeves.
    Type: Grant
    Filed: November 14, 1988
    Date of Patent: October 23, 1990
    Assignee: Varta Batterie Aktiengesellschaft
    Inventors: Klaus Ruggeberg, Horst-Udo Jose
  • Patent number: 4957832
    Abstract: A plastic sealing element for dry cells includes a radially symmetrical, centrally perforated base element, the upper side of which is provided with an elastomeric sealing material which is extruded in the form of a circumferential annular bead, and a process for its manufacture. After the sealing element is pre-assembled with the cell's metal housing cover and the cell is assembled, the annular bead is pressed flat during final crimping so that a sealing zone having a small cross section and defining a long leakage path is developed between the cover and the base element, effectively preventing the leakage of electrolyte or water vapor, which is especially diffuse from the cell's porous carbon rod conductor, into the cell's sealing zone.
    Type: Grant
    Filed: November 14, 1988
    Date of Patent: September 18, 1990
    Assignee: Varta Batterie Aktiengesellschaft
    Inventors: Klaus Ruggeberg, Horst-Udo Jose
  • Patent number: 4952861
    Abstract: A three-stage rapid charging process for maintenance-free lead storage batteries with a fixed electrolyte, which produces consistently recurring full charging of both electrode polarities even under cyclic loading, includes a first charging stage which proceeds at a constant current of the magnitude of a four-hour to eight-hour current until a temperature-dependent charging voltage is reached, a second charging stage which then continues at this temperature-dependent charging voltage for a limited time, and which is continuously adjusted to the battery's temperature, and a third charging stage which is again time-limited and which constitutes a secondary charging which proceeds according to an I/V characteristic curve with an initial charging current limited to between 0.05 and 0.5 times a ten-hour current and a battery voltage which is limited to between 2% and 8% above the temperature-dependent charging voltage.
    Type: Grant
    Filed: September 6, 1988
    Date of Patent: August 28, 1990
    Assignee: Varta Batterie Aktiengesellschaft
    Inventor: Karl G. Horn
  • Patent number: 4913989
    Abstract: A positive collector electrode with an active material which comprises a double hydroxide of the general formula[M.sup.2+ (1-x)Fe.sup.3+ x(OH).sub.2 ].sup.x+ [(x/n)X.sup.n-, yH.sub.2 O].sup.x-in which the transient parameter is 0.05.ltoreq.x.ltoreq.0.4, preferably 0.2, M.sup.2+ is preferably Ni.sup.2+, and X.sup.n- is an anion species, shows a remarkable improvement in electrical behavior as compared to analogous double hydroxides in which X.sup.n- is SO.sub.4.sup.2-, NO.sub.3.sup.- or CO.sub.3.sup.2-. These electrodes, known as siderophile electrodes, exhibit resistance to iron contamination if X.sup.n- is formed at least partly by PO.sub.4.sup.3- or HPO.sub.4.sup.2-. This improvement is manifested in a constancy of the specific discharge capacity at a high level over many cycles during charge/discharge operation as compared to a Cd/Cd(OH).sub.2 electrode. The process for producing the electrode is also disclosed.
    Type: Grant
    Filed: April 7, 1989
    Date of Patent: April 3, 1990
    Assignee: Varta Batterie Aktiengesellschaft
    Inventors: Oskar Glemser, Dieter H. Buss, Jurgen Bauer, Helga Low
  • Patent number: 4903753
    Abstract: In accordance with a new method of casting electrode grids for electric lead storage batteries in a mold, premature solidifying of the melt is prevented before the end of the mold filling period by an additional heating pulse applied to the melt during the mold filling process, as well as by the use of a good heat conducting mold material. The cooling down to the unmolding temperature is also accelerated. Because of the short dwell time of the lead within the mold, there simultaneously results a short machine cycling period. The separate pulse heating of the melt is preferably carried out by an induction heating apparatus, the alternating field of the inductor located within the mold walls producing heat through eddy current production within the molten molded body.
    Type: Grant
    Filed: March 27, 1986
    Date of Patent: February 27, 1990
    Assignee: Varta Batterie Aktiengesellschaft
    Inventor: Hans-Joachim Golz
  • Patent number: 4897323
    Abstract: A primary element is provided which is dischargeable at high temperatures comprising an alkaline electrolyte in a metallic annular cylindrical housing which encloses in inwardly directed concentric order: an outer positive silver oxide or manganese dioxide electrode in the form of a pressed powder cylinder and an inner negative electrode comprising a concentrically wound cadmium electrode wherein said negative electrode is separated from said positive electrode by a separator interposed therebetween. In storage and testing it has been shown that cells produced in accordance with the present invention may be kept at temperatures of the order of 200.degree. C. for over six weeks without any loss of operability.
    Type: Grant
    Filed: March 30, 1988
    Date of Patent: January 30, 1990
    Assignee: Varta Batterie Aktiengesellschaft
    Inventors: Rolf Hennrich, Heinz-Werner Nientiedt
  • Patent number: 4892637
    Abstract: A process which comprises thermally decomposing in an electrically heated vibrating helical conveyor, manganese carbonate (MnCO.sub.3 x H.sub.2 O) into a manganese oxide (predominantly of Mn.sub.2 O.sub.3 x Mn.sub.5 O.sub.8) catalyst at about 500.degree. C., and processing this catalyst into a highly active electrode paste by dry intensive mixing with a carbon-containing conductive material (carbon black, graphite or activated carbon) and PTFE as the binder. The resulting electrode paste can be rolled into a supporting net made from Ni or Ag. Also a two-step mixing process in which the catalyst powder is first premixed with small amounts of a conductive agent and a binder, compacted and granulated, and then combined with the larger residual amount of the intended amounts of conductive agent and binder in a second mixing step.
    Type: Grant
    Filed: June 23, 1988
    Date of Patent: January 9, 1990
    Assignee: Varta Batterie Aktiengesellschaft
    Inventors: Hans Sauer, August Winsel
  • Patent number: 4865928
    Abstract: For the effective removal of Joule heat from the interior of a high-performance lead battery, especially those with a fixed electrolyte, at least one of the negative grid plates which participate in the development of the electrodes are provided with a U-shaped tube which surrounds and is attached to the grid, in place of the usual grid frame, and through which a coolant circulates. Especially advantageous due to its capacity to conduct heat is a combination of a lead-coated, copper mesh grid and a copper tube, with a residual strip of unexpanded copper sheeting attached to the grid mesh along the remaining upper section of the frame, and developing the conducting lug.
    Type: Grant
    Filed: October 5, 1988
    Date of Patent: September 12, 1989
    Assignee: Varta Batterie Aktiengesellschaft
    Inventor: Gerolf Richter
  • Patent number: 4865927
    Abstract: Alkaline MnO.sub.2 /Zn cells having nickel-plated steel cups as the cathode collector show deterioration of their discharge characteristics after high-temperature storage, which can be prevented by an additive in the cathode paste which forms a strong complex with nickel. Nickel oxide layers of high ohmic resistance, which are the cause of the contact resistance between the cathode and the nickel coating of the steel cup, are accordingly dissolved or transformed. Imidazole, 2-picolinic acid, dimenthylglyoxime, 4,5-dihydroxbenzene-1,3-disulfonic acid and 1,10-phenanthroline are particularly effective additives for compounding into the cathode. Preferred amounts are between 0.001 wt. % and 1 wt. %.
    Type: Grant
    Filed: June 23, 1988
    Date of Patent: September 12, 1989
    Assignee: Varta Batterie Aktiengesellschaft
    Inventors: Helmut Laig-Horstebrock, Winfried Krey
  • Patent number: 4840857
    Abstract: There are provided primary cells comprising a negative lithium electrode and a positive CrO.sub.x cathode wherein 2.ltoreq..times..ltoreq.2.9. These cells are devoid of the conventional separator between the electrodes. Instead, there is provided at the outer face of the chromium oxide electrode, a barrier layer formed by the reaction of lithium and chromium oxide. The exact constitution of this barrier layer is not known. The barrier layer is ion conductive but not electro-conductive and has a substantially lower ohmic resistance than the conventional polypropylene or paper separators. There is thus provided a cell of high current capacity. Such cells can also be constructed utilizing magnesium dioxide, silver monoxide and disilver oxide or nickel hydroxide provided that said metal oxie cathodes are coated with a covering of chromium oxide.
    Type: Grant
    Filed: April 28, 1988
    Date of Patent: June 20, 1989
    Assignee: Varta Batterie Aktiengesellschaft
    Inventors: Subash-Chander Nijhawan, Horst Daniel, Welf Dennstedt