Patents Assigned to Derafe, Ltd.
  • Patent number: 5544681
    Abstract: Methods for fabricating cored structures are provided. The cored structures may particularly find usefulness as cored battery plates for use in lead/acid batteries. A pre-formed core element is provided, and on its surfaces there is placed a thin layer of an active surface material. That active surface material is one which may enter into a chemical or electrochemical process when in use and in the presence of an electrolyte or other agent which will promote such chemical or electrochemical process. In the case of lead/acid batteries, the active surface is lead or lead oxide. The core element is generally one which does not bond with the active surface material, but will if the active surface material is ion bombarded or neutral atom embedded into the surface of the core, and where the amount of bombardment or embedment is determined by controlling the accelerator voltage.
    Type: Grant
    Filed: June 1, 1994
    Date of Patent: August 13, 1996
    Assignee: Derafe, Ltd.
    Inventor: Robert S. Feldstein
  • Patent number: 5411821
    Abstract: An integral battery electrode structure for lead/acid battery plates is provided. The principle structure material is elemental lead or lead alloyed with antimony or calcium. At least the surface of the lead or alloy has an ion implanted or atomic embedded graded junction of at least one other atomic species, such as titanium, cadmium, or bismuth. Additionally, highly oxidative atomic species such as fluorine, chlorine, or metallic components such as titanium, tin, vanadium, chromium, or rhodium may be added at the surface of the lead or lead alloy. Optionally, an element such as cadmium, arsenic, uranium, barium or bismuth may be added at the surface and within several atomic layers below the surface in such a manner that the concentration may be from 0.05% to about 10.0% of the total mass in that region but that the total concentration in the electrode structure is from about 50 to about 350 parts per billion.
    Type: Grant
    Filed: June 10, 1993
    Date of Patent: May 2, 1995
    Assignee: Derafe, Ltd.
    Inventor: Robert S. Feldstein
  • Patent number: 5379502
    Abstract: Methods for fabricating battery plates for lead/acid batteries are provided. The battery plates that are fabricated may be positive plates, negative plates, or bipolar plates. The principal active constituent of the battery plates is elemental lead in the case of negative plates, lead oxide in the case of positive plates, or elemental lead on one face and lead oxide on the other face of bipolar plates. In any event, the battery plate comprises a thin layer of lead (which may later be oxidized, at least at its surface), where the thin layer of lead is surface treated so as to form a plurality of closely spaced depressions therein. By the surface treatment, the exposed active surface area of the plate is increased to at least 150% of its projected area. The surface treatment may be by embossing the lead, or micro-machining the lead using a laser. When the plate is a bipolar plate, a core element is provided between a pair of opposed thin layers of lead, one of which will subsequently be oxidized.
    Type: Grant
    Filed: June 10, 1993
    Date of Patent: January 10, 1995
    Assignee: Derafe, Ltd.
    Inventor: Robert S. Feldstein
  • Patent number: 5339873
    Abstract: Methods for fabricating cored structures are provided. The cored structures may particularly find usefulness as cored battery plates for use in lead/acid batteries. A pre-formed core element is provided, and on its surfaces there is placed a thin layer of an active surface material. That active surface material is one which may enter into a chemical or electrochemical process when in use and in the presence of an electrolyte or other agent which will promote such chemical or electrochemical process. In the case of lead/acid batteries, the active surface is lead or lead oxide. The core element is generally one which does not bond with the active surface material, but will if the active surface material is ion bombarded or neutral atom embedded into the surface of the core, and where the amount of bombardment or embedment is determined by controlling the accelerator voltage.
    Type: Grant
    Filed: June 10, 1993
    Date of Patent: August 23, 1994
    Assignee: Derafe, Ltd.
    Inventor: Robert S. Feldstein
  • Patent number: 5248475
    Abstract: Methods are provided for fabricating a sintered and solid element from an otherwise unsinterable material, utilizing the property of that material that it will form an eutectic composition or alloy with a suitable alloying agent at a temperature which is below the plastic deformation temperature of the material. Discrete particles of the material to be sintered--such as grains or wire pieces--are coated with a thin coating of the alloying agent and are packed into the position where they are to be sintered. Then, the coated grains or wire pieces are heated so that at least the coating and the regions of the grains just below the coating are slowly raised in temperature. Diffusion regions of the alloying agent into the grains of the sinterable material will then occur. Further heating continues so that at least the diffusion regions increase in temperature to just slightly above the eutectic melting point.
    Type: Grant
    Filed: October 24, 1991
    Date of Patent: September 28, 1993
    Assignee: Derafe, Ltd.
    Inventor: Robert S. Feldstein