Patents by Inventor Esther S. Takeuchi

Esther S. Takeuchi has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 7211349
    Abstract: An improved cathode material for nonaqueous electrolyte lithium electrochemical cell is described. The preferred active material is ?-phase silver vanadium oxide (Ag2V4O11) coated with a protective layer of a metal oxide, preferably ?-phase SVO (Ag1.2V3O1.8). The SVO core provides high capacity and rate capability while the protective coating reduces reactivity of the active particles with electrolyte to improve the long-term stability of the cathode.
    Type: Grant
    Filed: July 31, 2003
    Date of Patent: May 1, 2007
    Assignee: Wilson Greatbatch Technologies, Inc.
    Inventors: Randolph Leising, Esther S. Takeuchi
  • Patent number: 7118829
    Abstract: The current invention relates to the preparation of an improved cathode active material for non-aqueous lithium electrochemical cell. In particular, the cathode active material comprises ?-phase silver vanadium oxide prepared by using a ?-phase silver vanadium oxide starting material. The reaction of ?-phase SVO with a silver salt produces the novel ?-phase SVO possessing a lower surface area than ?-phase SVO produced from vanadium oxide (V2O5) and a similar silver salt as starting materials. Consequently, the low surface area ?-phase SVO material provides an advantage in greater long-term stability in pulse dischargeable cells.
    Type: Grant
    Filed: September 17, 2004
    Date of Patent: October 10, 2006
    Assignee: Wilson Greatbatch Technologies, Inc.
    Inventors: Randolph Leising, Esther S. Takeuchi
  • Patent number: 7108942
    Abstract: Electrochemical cells having the casing as part of the anode current collector are described. In particular, the anode is divided into two sections. In one section, lithium metal is pressed directly into contact with the inner surface of the casing. No anode current collector is needed in this section. In the other section, the anode is fabricated in a conventional manner in which lithium metal is pressed on to both sides of an anode current collector. Cathode materials can be, but are not limited to, SVO, CSVO, MnO2, LixCoO2, LixNiO2, LixMn2O4, V2O5, CFx, and mixtures thereof. Several non-active components are limited in this manner including an insulator bag, two layers of anode current collector and two layers of separator.
    Type: Grant
    Filed: March 23, 2004
    Date of Patent: September 19, 2006
    Assignee: Wilson Greatbatch Technologies, Inc.
    Inventors: Hong Gan, Esther S. Takeuchi
  • Patent number: 7092830
    Abstract: The present invention is directed to a method for analyzing the tail-end behavior of a lithium cell having a solid cathode. The tail of a longer-term accelerated discharge data (ADD) test is estimated from the tail of two shorter-term ADD tests. This is accomplished by first comparing the discharge tails of shorter-term ADD tests and determining angles or rotation that correspond to Rdc growth, and then trending rotation angles versus time to reach a give DoD. For example, the 18-month and 36-month ADD test tails are used to estimate the ADD test tail of a similarly constructed cell subjected to a longer-term ADD test, for example a 48-month ADD test.
    Type: Grant
    Filed: March 23, 2005
    Date of Patent: August 15, 2006
    Assignee: Wilson Greatbatch Technologies, Inc.
    Inventors: Kenneth Syracuse, Noelle Waite, Hong Gan, Esther S. Takeuchi
  • Patent number: 7068036
    Abstract: A model for estimating the discharge profile of a Li/CFx cell is described. The model uses as inputs the load at which the cell is subjected to and the planar surface area to estimate current density. Then, current density is used to estimate cell voltage at each 2% depth-of-discharge.
    Type: Grant
    Filed: October 28, 2004
    Date of Patent: June 27, 2006
    Assignee: WiWilson Greatbatch Technologies, Inc.
    Inventors: Kenneth C. Syracuse, Esther S. Takeuchi
  • Patent number: 7056358
    Abstract: A method for powering an implantable medical device with a lithium electrochemical cell having a sandwich cathode electrode of SVO/CFx/SVO active materials is described. A preferred cathode is of a ?-SVO/CFx/?-SVO or (?+?)-SVO/CFx/(?+?)-SVO sandwich configuration.
    Type: Grant
    Filed: May 9, 2003
    Date of Patent: June 6, 2006
    Assignee: Wilson Greatbatch Technologies, Inc.
    Inventors: Hong Gan, Esther S. Takeuchi
  • Patent number: 7052804
    Abstract: A new sandwich positive electrode design for a secondary cell is provided comprising a “sacrificial” alkali metal along with a cathode active material. In the case of silver vanadium oxide, the sacrificial alkali metal is preferably lithium. Upon activating the cells, the lithium metal automatically intercalates into the silver vanadium oxide. That way, the sacrificial lithium is consumed and essentially lithiates the silver vanadium oxide. This means that cathode active materials, such as silver vanadium oxide, which before now were generally only used in primary cells, are now useful in secondary cells. In some use applications, silver vanadium oxide is more desirable than typically used lithiated cathode active materials.
    Type: Grant
    Filed: December 4, 2002
    Date of Patent: May 30, 2006
    Assignee: Wilson Greatbatch Technologies, Inc.
    Inventors: Robert S. Rubino, Hong Gan, Esther S. Takeuchi
  • Patent number: 7033707
    Abstract: A lithium electrochemical cell of either a primary or a secondary chemistry activated with an electrolyte having a cyclic carbonate of a ring size equal to or larger than a six-member ring is described. The cyclic carbonate helps to make the anode passivation film ionically conductive to thereby eliminate voltage delay during pulse discharge and to reduce Rdc. Such a cell is particularly well suited for powering an implantable medical device, such as a cardiac defibrillator.
    Type: Grant
    Filed: February 19, 2003
    Date of Patent: April 25, 2006
    Assignee: Wilson Greatbatch Technologies, Inc.
    Inventors: Hong Gan, Esther S. Takeuchi
  • Patent number: 7026791
    Abstract: It is known that reforming implantable defibrillator capacitors at least partially restores and preserves their charging efficiency. An industry-recognized standard is to reform implantable capacitors by pulse discharging the connected electrochemical cell about once every three months throughout the useful life of the medical device. A Li/SVO cell typically powers such devices. The present invention relates to methodologies for significantly minimizing, if not entirely eliminating, the occurrence of voltage delay and irreversible Rdc growth in the about 35% to 70% DOD region by subjecting Li/SVO cells to novel discharge regimes. At the same time, the connected capacitors in the cardiac defibrillator are reformed to maintain them at their rated breakdown voltages.
    Type: Grant
    Filed: January 22, 2004
    Date of Patent: April 11, 2006
    Assignee: Wilson Greatbatch Technologies, Inc.
    Inventors: Marcus Palazzo, Esther S. Takeuchi, Randolph Leising
  • Patent number: 7022146
    Abstract: A hermetically sealed coin cell is described. The coin cell has the opposite polarity terminals isolated from one another by a glass-to-metal seal. Glassing a conductive disc inside a ring of greater diameter and height forms this seal. The height of the ring is equivalent to the desired height of the cell. The disc acts as one cell terminal, which can be positive or negative, and the ring serves as the other terminal. In plan view, both terminals are on the same side of the cell. This allows for easy mounting and connection to an electronic circuit board, and the like.
    Type: Grant
    Filed: November 1, 2005
    Date of Patent: April 4, 2006
    Assignee: Wilson Greatbatch Technologies, Inc.
    Inventors: Robert S. Rubino, Hong Gan, Joseph Prinzbach, Esther S. Takeuchi
  • Patent number: 7005214
    Abstract: A lithium/fluorinated carbon electrochemical cell having the CFx material supported on a titanium current collector screen sputter coated with a noble metal is described. The gold, iridium, palladium, platinum, rhodium and ruthenium-coated titanium current collector provides the cell with higher rate capability, even after exposure to high temperatures, in comparison to cells of a similar chemistry having the CFx contacted to a titanium current collector painted with a carbon coating.
    Type: Grant
    Filed: November 1, 2002
    Date of Patent: February 28, 2006
    Assignee: Wilson Greatbatch Technologies, Inc.
    Inventors: Esther S. Takeuchi, Bruce Platt, Sally Ann Smesko, Eric Ziarniak, Mark Roy
  • Patent number: 6984468
    Abstract: A hermetically sealed coin cell is described. The coin cell has the opposite polarity terminals isolated from one another by a glass-to-metal seal. Glassing a conductive disc inside a ring of greater diameter and height forms this seal. The height of the ring is equivalent to the desired height of the cell. The disc acts as one cell terminal, which can be positive or negative, and the ring serves as the other terminal. In plan view, both terminals are on the same side of the cell. This allows for easy mounting and connection to an electric circuit board, and the like.
    Type: Grant
    Filed: January 20, 2004
    Date of Patent: January 10, 2006
    Assignee: Wilson Greatbatch Technologies, Inc.
    Inventors: Robert S. Rubino, Hong Gan, Joseph Prinzbach, Esther S. Takeuchi
  • Patent number: 6982543
    Abstract: It is known that reforming implantable defibrillator capacitors at least partially restores and preserves their charging efficiency. An industry-recognized standard is to reform implantable capacitors by pulse discharging the connected electrochemical cell about once every three months throughout the useful life of the medical device. A Li/SVO cell typically powers such devices. The present invention relates to methodologies for accurately determining the precise boundaries of voltage delay and irreversible Rdc growth region in the about 25% to 70% DOD region so that more frequent pulse discharging for the purpose of cell reform is confined to the limits of the region. At the same time, the connected capacitors in the cardiac defibrillator are reformed to maintain them at their rated breakdown voltages.
    Type: Grant
    Filed: February 10, 2004
    Date of Patent: January 3, 2006
    Assignee: Wilson Greatbatch Technologies, Inc.
    Inventors: Kenneth Syracuse, Noelle Waite, Hong Gan, Esther S. Takeuchi
  • Patent number: 6951576
    Abstract: An anode-cathode sub-assembly for an electrochemical cell wherein a combination of an elongated alkali metal anode and elongated solid cathode within separator therebetween is wound using a mandrel to form the sub-assembly having a jellyroll type configuration and wherein the winding is performed in a manner so that upon removal of the mandrel from the completed sub-assembly, in the event any portion of the separator contacted by the mandrel is impaired, this will not cause an electrical short circuit in an electrochemical cell containing the sub-assembly.
    Type: Grant
    Filed: October 21, 1998
    Date of Patent: October 4, 2005
    Assignee: Wilson Greatbatch Ltd.
    Inventor: Esther S. Takeuchi
  • Patent number: 6936379
    Abstract: A method for providing a physician with an elective replacement indicator (ERI) for an implantable medical device is described. The medical device is powered by an electrochemical having a lithium anode coupled to a sandwich cathode comprising the configuration: SVO/current collector/CFx, with the SVO facing the anode. The indicator is predicated on when the cell's discharge capacity is nearing end-of-life (EOL) based on the theoretical capacity and the discharge efficiency of the SVO and CFx active materials. This serves as an indicator when it is time to replace the medical device.
    Type: Grant
    Filed: November 8, 2002
    Date of Patent: August 30, 2005
    Assignee: Wilson Greatbatch Technologies, Inc.
    Inventors: Hong Gan, Esther S. Takeuchi
  • Patent number: 6930468
    Abstract: It is known that reforming implantable defibrillator capacitors at least partially restores and preserves their charging efficiency. An industry-recognized standard is to reform implantable capacitors by pulse discharging the connected electrochemical cell about once every three months throughout the useful life of the medical device. A Li/SVO cell typically powers such devices. The present invention relates to methodologies for significantly minimizing, if not entirely eliminating, the occurrence of voltage delay and irreversible Rdc growth in the about 25% to 70% DOD region by subjecting Li/SVO cells to novel discharge regimes. At the same time, the connected capacitors in the cardiac defibrillator are reformed to maintain them at their rated breakdown voltages.
    Type: Grant
    Filed: September 9, 2003
    Date of Patent: August 16, 2005
    Assignee: Wilson Greatbatch Technologies, Inc.
    Inventors: Kenneth Syracuse, Noelle Waite, Hong Gan, Esther S. Takeuchi
  • Patent number: 6926991
    Abstract: A new cathode design has a first cathode active material of a relatively low energy density but of a relatively high rate capability contacted to a first cathode current collector and a second cathode active material having a relatively high energy density but of a relatively low rate capability in contact with a second cathode current collector, is described. The first and second cathode current collectors are connected to a common terminal lead. The present cathode design is useful for powering an implantable medical device requiring a high rate discharge application.
    Type: Grant
    Filed: December 23, 2002
    Date of Patent: August 9, 2005
    Assignee: Wilson Greatbatch Technologies, Inc.
    Inventors: Hong Gan, Esther S. Takeuchi
  • Patent number: 6919141
    Abstract: A lithium ion electrochemical cell having high charge/discharge capacity, long cycle life and exhibiting a reduced first cycle irreversible capacity, is described. The stated benefits are realized by the addition of at least one phosphate additive having the formula: (R1O)P(?O) (OR2) (OR3) and wherein R1, R2 and R3 are the same or different, wherein at least one, but not all three, of the R groups is hydrogen, or at least one of the R groups has at least 3 carbon atoms and contains an sp or sp2 hybridized carbon atom bonded to an sp3 hybridized carbon atom bonded to the oxygen atom bonded to the phosphorous atom.
    Type: Grant
    Filed: September 20, 2002
    Date of Patent: July 19, 2005
    Assignee: Wilson Greatbatch Technologies, Inc.
    Inventors: Hong Gan, Esther S. Takeuchi, Robert Rubino
  • Patent number: 6872490
    Abstract: The current invention provides a method of preparing a cathode material in a sequential two-part reaction process. In the first step, silver nitrate and vanadium oxide are decomposed by heat under an inert atmosphere. In the second part of the process, the resulting intermediate material is heat treated under an oxidizing atmosphere. The sequential combination of steps produces a highly crystalline silver vanadium oxide cathode material which has properties not heretofore exhibited by SVO prepared by prior art methods.
    Type: Grant
    Filed: August 8, 2002
    Date of Patent: March 29, 2005
    Assignee: Wilson Greatbatch Technologies, Inc.
    Inventors: Randolph Leising, Esther S. Takeuchi
  • Patent number: 6844115
    Abstract: The present invention is directed to at least partially replacing PC and/or DME with a linear carbonate, preferably dimethyl carbonate, and a linear mono-ether, the most preferred being diisopropyl ether, in electrolytes useful for activating alkali metal-containing cells. This electrolyte has improved conductivity and provides electrochemical cells with enhanced discharge performance. A most preferred electrolyte comprises 1,2-dimethoxyethane, propylene carbonate, dimethyl carbonate and diisopropyl ether.
    Type: Grant
    Filed: November 4, 2002
    Date of Patent: January 18, 2005
    Assignee: Wilson Greatbatch Technologies, Inc.
    Inventors: Hong Gan, Esther S. Takeuchi