Patents Assigned to Valence Technology
  • Patent number: 6294288
    Abstract: The invention provides a battery cell including an electrode having an area defined by a perimeter including an edge, a counter electrode having an area defined by a perimeter including an edge, and a separator having an area defined by a perimeter including an edge. The separator is sandwiched between the electrode and the counter electrode in a layered relationship with at least portions of the edges being contiguous. The separator and one of the electrode and the counter electrode each include a first notch in the edge exposing a portion of the other of the electrode and counter electrode. The separator and the other of the electrode and the counter electrode each include a second notch in the edge exposing a portion of the one of the electrode and the counter electrode.
    Type: Grant
    Filed: December 1, 1999
    Date of Patent: September 25, 2001
    Assignee: Valence Technology, Inc.
    Inventor: Oliver J. Gross
  • Patent number: 6291097
    Abstract: Disclosed herein is a battery design for bi-cell polymer matrix batteries. Each bi-cell comprises, sequentially, a first counter electrode, a first separator membrane, a centrally located electrode, a second separator membrane, and a second counter electrode. The current collector of each of the counter electrodes is positioned other than medially within the counter electrode. Generally, the current collector of the counter electrode is located within the outer half of the counter electrode. When the current collector is located at the extreme outer edge of the counter electrode, a capping film of polymer matrix material is preferably laminated to the perforated current collector, and, through the perforated current collector, to the counter electrode material itself.
    Type: Grant
    Filed: May 11, 2000
    Date of Patent: September 18, 2001
    Assignees: Valence Technology, Inc., Delphi Technologies, Inc.
    Inventors: Jeremy Barker, Wade Guindy, Howard Kisner, Porter Mitchell, Mohammad Parsian
  • Patent number: 6242128
    Abstract: A fastener system for tab bussing for the multicell batteries and the apparatus to assist this system are described. The holding device is used to hold the tab bussing structure together. The holding device can be a bolt or a rivet. It minimizes the electrical resistance of the multicell battery, allows rework and achieves high energy efficiency and small dimensions for the multicell lithium-polymer batteries.
    Type: Grant
    Filed: December 6, 1993
    Date of Patent: June 5, 2001
    Assignee: Valence Technology, Inc.
    Inventors: Drew Tura, David Brongiel
  • Patent number: 6203946
    Abstract: The invention provides an electrochemical cell which comprises a first electrode and a second electrode which is a counter electrode to said first electrode. The first electrode comprises a phosphorous compound of the nominal general formula Li3E′aE″b(PO4)3, desirably at least one E is a metal; and preferably, Li3M′M″(PO4)3. E′ and E″ are the same or different from one another. Where E′ and E″ are the same, they are preferably metals having more than one oxidation state. Where E′ and E″ are different from one another, they are preferably selected from the group of metals where at least one of E′ and E″ has more than one oxidation state.
    Type: Grant
    Filed: December 3, 1998
    Date of Patent: March 20, 2001
    Assignee: Valence Technology, Inc.
    Inventors: Jeremy Barker, M. Yazid Saidi
  • Patent number: 6183718
    Abstract: A method for forming the composition stabilized against capacity degradation comprises particles of spinel lithium manganese oxide (LMO) enriched with lithium by a decomposition product of lithium carbonate forming a part of each said particle and characterized by a reduced surface area and increased capacity expressed in milliamp hours per gram as compared to non-enriched spinel.
    Type: Grant
    Filed: May 7, 1999
    Date of Patent: February 6, 2001
    Assignee: Valence Technology, Inc.
    Inventors: Jeremy Barker, M. Yazid Saidi, Chariclea A. Scordilis-Kelley
  • Patent number: 6174623
    Abstract: An electro-active compound particulate coated with a conducting polymer composition finds use in electrochemical cell electrodes.
    Type: Grant
    Filed: March 8, 1994
    Date of Patent: January 16, 2001
    Assignee: Valence Technology, Inc.
    Inventor: Dale R. Shackle
  • Patent number: 6168880
    Abstract: The use of a polymer mesh made of material that melts under thermal runaway helps improve the safety of an electrochemical device. The mesh material can increase the impedance of the battery during the thermal runaway and absorb some of the heat produced.
    Type: Grant
    Filed: June 26, 1997
    Date of Patent: January 2, 2001
    Assignees: Valence Technology, Inc., General Motors Corp
    Inventors: Kent Snyder, Wei Liu, Zhen Yang
  • Patent number: 6156458
    Abstract: A solid electrolyte containing a polymeric matrix, a salt, a solvent, and a toughening agent, is provided. The toughening agent may include alumina, silica, zeolite, and metal oxides (e.g., calcium oxide and magnesium oxide), and mixtures thereof. The toughening agent acts as a drying agent to remove excess solvent in the electrolyte. The solid electrolyte have improved mechanical strength and adherence to the anode and cathode.
    Type: Grant
    Filed: October 23, 1996
    Date of Patent: December 5, 2000
    Assignee: Valence Technology, Inc.
    Inventors: Ralph Brodd, Benjamin Chaloner-Gill, Milton Neal Golovin, Mark Isaacson, Joseph Lundquist
  • Patent number: 6153333
    Abstract: The invention provides novel lithium-containing phosphate materials having a high proportion of lithium per formula unit of the material. Upon electrochemical interaction, such material deintercalates lithium ions, and is capable of reversibly cycling lithium ions. The invention provides a rechargeable lithium battery which comprises an electrode formed from the novel lithium-containing phosphates.
    Type: Grant
    Filed: March 23, 1999
    Date of Patent: November 28, 2000
    Assignee: Valence Technology, Inc.
    Inventor: Jeremy Barker
  • Patent number: 6150050
    Abstract: In one aspect, the invention provides a method for recovering particulate material from a component of an electrochemical cell. In another aspect, a method is provided for recovering metal oxide particulate active material. The metal oxide is effectively separated from other cell components and is rendered to a form reusable as an active material for a new electrochemical cell. In still another aspect, a method is provided for recovering lithium metal oxide particulate active material and for regenerating the lithium metal oxide active material back to its initial nominal condition usable as battery grade material in an electrochemical cell. In the latter aspect, the invention provides the capability of treating lithium-deficient metal oxide active material which has become lithium-deficient from repeated cycling in a cell. The lithium-deficient active material is characterized by a lesser lithium content as compared to its nominal initial condition before cycling in a cell.
    Type: Grant
    Filed: March 9, 1998
    Date of Patent: November 21, 2000
    Assignee: Valence Technology, Inc
    Inventors: Santosh Mathew, Krishna Menon, Chariclea Scordilis-Kelley, M. Yazid Saidi
  • Patent number: 6136472
    Abstract: The invention provides a new electrode active material and cells and batteries which utilize such active material. The active material is represented by the nominal general formula Li.sub.a M'.sub.(2-b) M".sub.b Si.sub.c P.sub.(3-c) O.sub.12, 0.ltoreq.b.ltoreq.2, 0<c<3. M' and M" are each elements selected from the group consisting of metal and metalloid elements. The value of the variable a depends upon the selection of M' and M" and on the relative proportions designated as b and c.
    Type: Grant
    Filed: June 26, 1998
    Date of Patent: October 24, 2000
    Assignee: Valence Technology, Inc.
    Inventors: Jeremy Barker, M. Yazid Saidi
  • Patent number: 6103419
    Abstract: Provided by the present invention is a new cathode material comprised of a lithiated zirconium, titanium or hafnium oxide. The oxide is of the formula Li.sub.2 MXO.sub.4, where M is preferably a transition metal such as Ni, Co, Fe, Mn, V, Cu, or Cr, and X is zirconium, titanium or hafnium. The cathode material provides a useful composite cathode when combined with a polymeric binder and carbon.
    Type: Grant
    Filed: September 6, 1996
    Date of Patent: August 15, 2000
    Assignee: Valence Technology, Inc.
    Inventors: M. Yazid Saidi, Jeremy Barker, Rene Koksbang
  • Patent number: 6096101
    Abstract: Anodes, cathodes, and/or solid electrolytes (or separator layers) of an electrochemical cell can be fabricated from aqueous compositions containing monomers and/or polymers. In one formulation, the aqueous composition contains binding materials that are polymerized and crosslinked. In a second formulation, the composition is a latex having as aqueous phase and a solid polymer phase. Upon removal of water, the compositions provide a polymeric structure suitable for use as an electrode or solid electrolyte.
    Type: Grant
    Filed: March 5, 1997
    Date of Patent: August 1, 2000
    Assignee: Valence Technology, Inc.
    Inventors: Peikang Liu, Porter Mitchell, Feng Gao
  • Patent number: 6077624
    Abstract: The methods and compositions of the invention provide two solutions to reduce the reactivity of VDF-based copolymers to lithiated graphite. The two approaches can be used separately or combined. In one embodiment, the relative proportion of the VdF and the other fluorinated monomer (OFM, i.e. HFP) in the copolymer is significantly reduced below conventional formulations in order to reduce the reactivity of the copolymer. In a second approach, the reactivity of the copolymer, over a broad range of monomer VdF:OFM molar ratios, is reduced by deactivating the reactive sites on the copolymer, thereby blocking the ability to undergo undesired reaction during cell operation. These methods and compositions have heretofore not been proposed and are of primary importance in preventing large exothermic reaction which can lead to thermal runaway when conventional polymer formulations are utilized in batteries in the presence of reactive components such as lithiated graphite.
    Type: Grant
    Filed: August 14, 1997
    Date of Patent: June 20, 2000
    Assignee: Valence Technology, Inc.
    Inventors: Porter H. Mitchell, Jeremy Barker, Tracy E. Kelley
  • Patent number: 6063519
    Abstract: Disclosed herein is a battery design for bi-cell polymer matrix batteries. Each bi-cell comprises, sequentially, a first counter electrode, a first separator membrane, a centrally located electrode, a second separator membrane, and a second counter electrode. The current collector of each of the counter electrodes is positioned other than medially within the counter electrode. Generally, the current collector of the counter electrode is located within the outer half of the counter electrode. When the current collector is located at the extreme outer edge of the counter electrode, a capping film of polymer matrix material is preferably laminated to the perforated current collector, and, through the perforated current collector, to the counter electrode material itself.
    Type: Grant
    Filed: May 15, 1998
    Date of Patent: May 16, 2000
    Assignee: Valence Technology, Inc.
    Inventors: Jeremy Barker, Wade Guindy, Howard Kisner, Porter Mitchell, Mohammad Parsian
  • Patent number: 6048645
    Abstract: In one embodiment, the invention provides a novel active material which is a lithium-rich, manganese oxide active material in the form of a single phase tetragonal crystal structured Li.sub.2 Mn.sub.2 O.sub.4 compound having lattice parameters a=b=5.665 .ANG..+-.0.003 .ANG., and c=9.265 .ANG..+-.0.003 .ANG.. A unique characteristic of the compound is that when lithium ions are deintercalated (extracted) from the Li.sub.2 Mn.sub.2 O.sub.4 at first and second voltage plateaus, the crystal structure is transformed to a cubic structure characterized by lattice parameters a=b=c=8.235 .ANG..+-.0.004 .ANG.. On subsequent charge and discharge of the battery, corresponding to subsequent extraction and reinsertion of lithium into the electrode material at the second voltage plateau, the cubic structure is maintained.
    Type: Grant
    Filed: August 21, 1997
    Date of Patent: April 11, 2000
    Assignee: Valence Technology, Inc.
    Inventors: Mohamed-Yazid Saidi, Jeffrey L. Swoyer
  • Patent number: 6042966
    Abstract: The subject invention provides a battery pouch or container which is highly resistant to shorting. This electrical protection is produced by a folding of the packaging laminate such that the cut edge of the laminate is physically removed and electrically protected from the electrode tab which protrudes from the battery pouch. In one embodiment, the cut edge of the film is folded away from the electrode tab. In a preferred embodiment, the laminar packaging material includes a convex flap of material where the electrode traverses the package. The convex flap is folded away from the electrode tab without wrinkling or distorting the pouch shape. In an alternate embodiment, an intervening layer of insulative material is placed between the cut edge and the electrode tab.
    Type: Grant
    Filed: January 20, 1998
    Date of Patent: March 28, 2000
    Assignee: Valence Technology, Inc.
    Inventor: S. Scot Cheu
  • Patent number: 6040085
    Abstract: The subject invention discloses apparatus and methods to provide compression of an electrochemical cell independent of atmospheric pressure. One aspect of this invention is directed towards a lithium ion cell assembly which is surrounded by a layer of material under tension, so that the material applies pressure which compresses the cell to enhance contact between the anode, separator, and cathode layers. Specifically, a heat shrink material (material which reduces in size, or contracts in at least one dimension of a three-dimensional conformation, due to the application of heat) is provided about a laminar battery and shrunk in situ to provide a battery package. Another embodiment of this invention is directed towards a lithium ion cell asembly in which a sealed package contains both the battery and a spring element. The spring element within the package applies pressure to the battery to compress it and improve contact between the anode, separator, and cathode layers.
    Type: Grant
    Filed: March 4, 1997
    Date of Patent: March 21, 2000
    Assignee: Valence Technology, Inc.
    Inventors: S. Scot Cheu, Russell D. Moulton
  • Patent number: 6020087
    Abstract: A method of improving the structural integrity of polymer electrolytes of electrochemical cells by employing lithiated fillers that are represented by the formula Li.sub.16-2x D.sub.x (TO.sub.4).sub.4 where 0<x<4, D is Zn or Mg and T is Si or Ge.
    Type: Grant
    Filed: January 30, 1998
    Date of Patent: February 1, 2000
    Assignee: Valence Technology, Inc.
    Inventor: Feng Gao
  • Patent number: RE37076
    Abstract: Non-aqueous electrochemical cells with improved performance can be fabricated by employing anodes comprising a composition having graphite particles that have a BET method specific surface area of about 6 to about 12 m2/g and a crystallite height Lc of about 100 nm to about 120 nm, and wherein at least 90% (wt) of the graphite particles are less than 16 &mgr;m in size; a cathode; and a non-aqueous electrolyte containing a solvent and salt that is interposed between the anode and cathode. When employed in an electrochemical cell, the anode can attain a specific electrode capacity of at least 300 mAhr/g. The electrochemical cell has a cycle life of greater than 1500 cycles, and has a first cycle capacity loss of only about 10% to about 15%.
    Type: Grant
    Filed: January 8, 1999
    Date of Patent: February 27, 2001
    Assignee: Valence Technology, Inc.
    Inventor: Jeremy Barker