Abstract: This invention is directed to novel allyl silane monomers and to solid electrolytes containing a solid polymeric matrix having incorporated therein allyl silane monomers. The solid electrolytes are used in electrolytic cells.
Abstract: The inventions provides a battery which comprises a first electrode, a counter electrode which forms an electrochemical couple with said first electrode, and an electrolyte. The first electrode comprises graphite particles having an interlayer distance spacing of 002 planes (d.sub.002) as determined by x-ray diffraction of 0.330 to 0.340 nanometers (nm), a crystallite size in the direction of c-axis (L.sub.c) being greater than about 90 nanometers (nm) and less than about 1000 nanometers, and at least 90 percent by weight of said graphite particles having a size less than about 24 microns (.mu.m). The electrolyte comprises a solvent mixture and a solute; the solvent mixture comprises (i) ethylene carbonate (EC), and (ii) a solvent selected from the group consisting of propylene carbonate (PC), butylene carbonate (BC), and mixtures thereof with the ethylene carbonate being present in an amount by weight which is at least as great as the amount of any other solvent.
Abstract: This invention is directed to lithium and lithium alloy metal substrates, coated with a polymeric layer containing dispersed lithium or lithium alloy metal particles. The coated metal finds use as anode material in solid electrochemical cells.
Abstract: This invention is directed to a photoelectrochemical cell having increased conductivity. The cell employs an electrolyte formed from a polymeric matrix, an electrolytic solvent, an inorganic ion salt and a redox couple.
Abstract: This invention is directed to solid electrolytes containing a solvent and, in particular, a solvent comprising a mixture of an organic carbonate and triglyme as well as electrolytic cells prepared from such solid electrolytes.
Type:
Grant
Filed:
July 22, 1992
Date of Patent:
April 15, 1997
Assignee:
Valence Technology, Inc.
Inventors:
Milton N. Golovin, Dale R. Shackle, Russel D. Moulton
Abstract: The present invention provides cathode active materials having as their major component or consisting essentially entirely of an oxide of vanadium of one of the nominal general formulas: Li.sub.a Fe.sub.x V.sub.y O.sub.z and Li.sub.m Fe.sub.x V.sub.y O.sub.z. In the case of Li.sub.a Fe.sub.x V.sub.y O.sub.z the material in an initial condition does not contain any lithium so a is equal to 0. In the case of Li.sub.m Fe.sub.x V.sub.y O.sub.z the material in an initial condition contains lithium so m is greater than 0. In both cases, x is about 1, y is about 3, and z is about 8. In both cases, the V(4) state is achieved by reaction between iron and V(5) in vanadium pentoxide. In one case lithium was added by including lithium hydroxide in an aqueous solution containing the iron and the vanadium pentoxide.
Abstract: A method of fabricating electrodes suitable for use in electrochemical cells is provided. Each electrode has a perforated current collector and a tab which form an integral unit. The method can be adapted for batch, semi-continuous, or continuous fabrication of electrodes having electrode material laminated onto one or both surfaces of the current collector.
Type:
Grant
Filed:
April 10, 1996
Date of Patent:
April 1, 1997
Assignee:
Valence Technology, Inc.
Inventors:
David A. Velasquez, Douglas B. Holmes, E. Lawrence Gogolin
Abstract: A method of preparing an electrochemical cell wherein the composite electrode material adheres to the current collector to create good electrical contact is provided. The electrode/current collector comprises a current collector having a layer of electrically conductive metal oxide on at least one surface of the current collector and a composite electrode selected from the group consisting of composite cathode and composite anode wherein the layer of metal oxide is positioned between the current collector and composite electrode. The composite electrode remains substantially and permanently attached to the electrically conductive metal oxide layer that has been formed on the surface(s) of the current collector during the life of the electrochemical cell or battery.
Abstract: In a new process for making an electrode current collector assembly, an electrode composition is mixed with a volatile casting solvent and is coated onto a substrate. Then, the coated substrate is heated to drive off a major portion of the volatile casting solvent. Next, force is applied on an external surface of the coating and directed toward the substrate so as to compact the coating and reduce the volume of pore spaces in the coating. An electrolyte composition may be applied to the compacted electrode composition either before or after curing. The electrode and electrolyte compositions are each cured. In a final step, a counter-electrode layer is applied onto the electrolyte composition to form a cell assembly.
Abstract: A secondary, solid electrolytic battery includes a number of electrically connected electrolytic cells wherein for each cell the anode and cathode are separated from each other by a mask that is a layer of electrically insulative material that is coated along the perimeter of the anode and/or cathode. The mask reduces the rate of dendrite formation and prevents edge-effects, short circuits, and related problems caused by inadvertent contact of the anode and cathode.
Abstract: In making a laminar assembly for use in the battery, a layer of battery electrode material is deposited onto a substrate surface and the battery electrode material is caused to have an uneven surface. Then an electrolyte layer is deposited onto the uneven surface of the battery electrode material. Where the method calls for first depositing the electrolyte material, then electrolyte material is deposited onto the substrate layer where the electrolyte layer is caused to have an uneven surface. Thereafter, the battery electrode material is deposited onto the uneven surface of the electrolyte material. In both cases, slippage between the battery electrode material and electrolyte material is reduced during cutting, folding and other handling process in making a laminar battery, thereby reducing the probability of shorts in the battery.
Type:
Grant
Filed:
August 2, 1994
Date of Patent:
February 25, 1997
Assignee:
Valence Technology, Inc.
Inventors:
Gert L. Jensen, Benjamin Chaloner-Gill, Mark J. Isaacson
Abstract: This invention is directed to a solid electrolyte containing a polymeric matrix, a salt, a solvent and a viscosifying agent containing a reactive group as well as electrolytic cells prepared from such solid electrolytes.
Abstract: A method of increasing the amount of alkali metal that is available during charge/discharge of an electrochemical cell that employs carbon based intercalation anodes is provided. The method comprises of prealkaliation of the carbon anode. By subjecting the anode carbon to the prealkaliation process prior to packaging the electrochemical cell, substantially all the alkali metal (e.g., lithium) which is originally present in the cathode will be available for migration between the anode and cathode during charge/discharge.
Abstract: A method of preparing an electrochemical cell wherein the electrode material adheres to the current collector to create good electrical contact is provided. A critical aspect in the process of preparing the polymer mixture for both the anode and cathode slurries is that the polymer (or copolymer) not be subject to high shear so as to be degraded. Polymer degradation contributes to the creation of the polymer concentration gradient in the electrode film.
Abstract: An apparatus for forming a laminate having a smooth surface includes a planar member having, on at least one side thereof, desired surface roughness characteristics, is forced against the material layer on the substrate such that the material layer attains substantially the same surface roughness characteristics as the one side of the planar member.
Abstract: Disclosed is a continuous process for the synthesis of electrode-quality metal oxide particles by the thermal decomposition of ammonium metal oxides in a fluidized bed under oxidation/reduction conditions which are controlled by the temperature and ammonium content of the process gas.
Abstract: The state of charge of a cell that has flexible packaging and that expands and contracts with variations in state of charge is determined by measuring changes in thickness of the cell. The invention is particularly applicable to cells having a flat geometry. A battery having a state-of-charge indicator includes at least one battery cell free to expand and contract with variations in state of charge of the battery cell and a device for measuring expansion or contraction of the battery cell, a resulting measurement indicating the state of charge of the battery cell. By measuring expansion or contraction of the battery the state of charge of a battery may be readily detected. The measurement may be directly displayed so as to be visually observable, or a signal containing measurement information may be sent to a remote location to be displayed or used for control purposes.
Abstract: In a new process for making a cathode current collector assembly, a cathode composition is positioned on a substrate between the substrate and a releasable layer. Next, force is applied on the releasable layer and directed toward the substrate so as to provide a smooth cathode surface in contact with the releasable layer. The cathode composition having the releasable layer maintained thereon is cooled to reduce the tackiness of the cathode composition and then the releasable layer is removed while the cathode composition remains in its condition of reduced tackiness. In an alternative process, the cathode composition is applied and then force is applied immediatly before or simultaneously with cooling the composition to a state of reduced tackiness. An electrolyte composition is applied to the smooth surface cathode and the cathode and electrolyte compositions are cured together. In a final step, an anode layer is applied onto the electrolyte composition to form a cell assembly and further curing may occur.
Abstract: Disclosed are methods for extending the cycle life of solid, secondary electrolytic cells employing a solid electrolyte having at least about 100 ppm water which methods involve an initial, substantially constant, high rate discharge of the fabricated, charged electrolytic cell.
Type:
Grant
Filed:
April 19, 1993
Date of Patent:
July 25, 1995
Assignee:
Valence Technology, Inc.
Inventors:
Joseph Lundquist, Benjamin Chaloner-Gill