Abstract: A material for a negative electrode capable of preventing change in the volume of an active material occurring when lithium is doped/dedoped to improve resistance against cycle operations. A material for a negative electrode contains a mixture of a non-carbon material and a carbon material, wherein when an assumption is made that the average particle size of the non-carbon material is RM and the average particle size of the carbon material is RC, the ratio RM/RC is not higher than one, and when an assumption is made that the weight of the non-carbon material is WM and the weight of the carbon is WC, the ratio WM/WC is not higher than one or a mixture of a silicon compound and a carbon material, wherein when an assumption is made that the average particle size of the silicon compound is RSi and the average particle size of the carbon material is RC, the ratio RSi/RC is not higher than one.

Abstract: This invention is an electrode for a non-aqueous electrolytic cell, in which a collector is coated with an electrode active material layer comprising an active material, flake graphite and a binder, which is characterized by that the central particle size of the graphite is larger than that of the active material, and the following equation is satisfied, when the particle size of the active material is taken as r, the particle size distribution of the active material as f(r), the density of the active material as d, the specific surface area according to the BET method of the graphite as Sg, and the weight of the active material in an electrode coating film as Mg, and provides an electrode for a secondary cell which can give high capacity to the cell and enhance the flexibility of the cell: 9 · Ma d ⁢ ∫ 0 ∞ ⁢

Abstract: A secondary battery with non-aqueous electrolyte having a high voltage and energy density and a superior cycle property, characterized in that a cathode comprises composite oxides containing lithium and an anode comprises composite carbon materials containing graphite spherical particles and carbon fibers. The carbon fiber improves the stiffness of the anode depolarizing mix to prevent the body made thereof from swelling and decomposing.

Abstract: By using a porous material formed by calcining an active material as an electrode of a non-aqueous solvent secondary battery, the volume of a dead space in the electrode contained in a container of the constituted battery is reduced, thereby to increase an electric capacity per unit volume. By using the porous material as the electrode material, rather a powder material, the active material is sufficiently brought into contact with an electrolyte solution, electrically. Furthermore, the amount of a metal foil as a current collecting material and a conductive material are reduced or use of them is made unnecessary, and an electric capacity per unit weight is increased in comparison with the prior art. When the porous sintered material has a plate-like shape, the thickness is from 100 &mgr;m to 2 mm. The porous sintered material contains pores of an average diameter of 0.

Abstract: The present invention provides a rechargeable lithium electrochemical cell comprising an electrolyte containing a lithium salt dissolved in a non-aqueous solvent, at least one positive electrode, and at least one negative electrode of the paste type containing an electrochemically active material which is a carbon compound suitable for inserting lithium ions and a binder, the cell being characterized in that said solvent contains at least one saturated cyclic carbonate and at least one linear ester of a saturated aliphatic monocarboxylic acid, and in that said binder is a polymer having no fluorine.

Abstract: An electrode for a battery includes an electrode sheet, a lead, and a metal piece. The electrode sheet has a collector, an active material layer formed on the collector, and a lead connecting portion which is configured as an exposed extension of the collector, on both surfaces of which the active material layer is not formed. The lead connecting portion, the lead, and the metal piece are overlapped to and joined to each other. With this configuration, even if a contact area between the lead connecting portion and the lead is small, an electric resistance at the joined portion between the lead connecting portion and the lead becomes small, with a result that it is possible to enhance the strength of the joined portion and to enhance the discharge load characteristic of the battery.

Abstract: Electrolyte compositions and electrochemical systems containing such compositions are described where the electrolyte includes in a matrix material a combination of a conductive salt and a bis(perfluoroalkanesulfonyl)imide surfactant salt. The compositions improve wettability of electrodes and separators while maintaining and improving conductivity, stability, and compatibility with other cell components.

Abstract: A solid electrolyte cell in which the state of electrical contact between the solid electrolyte and the layers of active materials of the positive and negative electrodes and the inter-particulate distance in the layers of active materials of the positive and negative electrodes can be optimized to assure superior load characteristics, and a method for manufacturing the cell. The method for manufacturing a solid electrolyte cell includes a step of applying a paint containing an active material and a binder to a current collector to form a layer of an active material, and a step of impregnating a solid electrolyte in the layer of the active material formed by the active material layer forming step. The impregnating step includes applying the paint comprised of the solid electrolyte dissolved in a solvent on the layer of the active material to allow the paint to be permeated into the layer of the active material, and subsequently drying the solvent.

Abstract: A gel electrolyte secondary cell in which discharge capacity loss can be suppressed even with the use of a graphitized carbonaceous material of a small particle size as a negative electrode material to assure low impedance, superior cell voltage and load characteristics and high charging/discharging efficiency. To this end, a graphitized carbonaceous material prepared by firing meso-carbon micro-beads is used as a material for a negative electrode 9.

Abstract: This invention pertains to separators for use in electrochemical cells which comprise at least one microporous pseudo-boehmite layer, which separator is in contact with at least one protective coating layer positioned on the anode-facing side of the separator opposite from the cathode active layer in the cell; electrolyte elements comprising such separators; electrical current producing cells comprising such separators; and methods of making such separators, electrolyte elements and cells.

Abstract: Carbon fiber having cross sectional shape which satisfies area replenishment rate of 0.8 or more is used as anode material for non-aqueous electrolyte secondary battery. Alternatively, since value of fractal dimension of cross section high order structure of the random radial type carbon fiber can be utilized as material parameter for evaluating the cross sectional structure, carbon fiber in which the value of the fractal dimension is caused to fall within the range from 1.1 to 1.8 and the crystallinity has been controlled such that it falls within reasonable range is used as anode material for non-aqueous electrolyte secondary battery. Further, carbon fiber having cross section high order structure such that the central portion is radial type structure and the surface layer portion is random radial type structure is used as anode material for non-aqueous electrolyte secondary battery. Furthermore, it is also effective to use carbon fiber having notch structure at the cross section.

Abstract: A carbonaceous material for use as an anode material in secondary batteries using non-aqueous solvent comprises calcining a solid obtained by heating tar and/or pitch with furfural in the presence of an acid catalyst, the use of the resulting anode material imparting to the battery a relatively large capacity while having only a small irreversible capacity loss in the first cycle.

Abstract: The present invention provides a method of manufacturing an organic electrolyte electrochemical cell comprising at least one electrochemical couple made up of two electrodes sandwiching a solid film of porous polymer containing said electrolyte, each electrode comprising a porous layer containing an electrochemically active material and a binder, the method comprising the following steps:

Abstract: Lithium electrochemical cells and batteries are described having electron conductive additives in the form of a mixture of carbon fibres and fine carbon particles. The electron conductive additives are provided in a polymeric fluoride coating between the electrode and the current collector. A mixture of carbon fibres and fine carbon can also be admixed with the cathode-active component in the cathode.

Abstract: A lithium secondary battery includes: an internal electrode body including a positive electrode, a negative electrode, and a separator, the positive electrode and the negative electrode being wound via the separator so that the positive electrode and the negative electrode are not brought into direct contact with each other, and an organic electrolyte. An average current collecting area obtained by dividing a positive electrode area (cm2) by the number of current-collecting tabs to be attached to the positive and negative electrodes is 360 or less.

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 carbonate additive to an electrolyte comprising an alkali metal salt dissolved in a solvent mixture that includes ethylene carbonate and an equilibrated mixture of dimethyl carbonate, ethylmethyl carbonate and diethyl carbonate. The preferred additive is either a linear or cyclic carbonate containing covalent O—X and O—Y bonds on opposite sides of a carbonyl group wherein at least one of the O—X and the O—Y bonds has a dissociation energy less than about 80 kcal/mole.

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 phosphonate additive having the formula (R1O)P(═O) (OR2) (R3) provided in the electrolyte. In the phosphonate formula, R3 is a hydrogen atom and wherein at least one, but not both, of R1 and R2 is a hydrogen atom and the other of R1 and R2 is an organic group containing 1 to 13 carbon atoms. Or, at least one of R1 and R2 is an organic group containing at least 3 carbon atoms and having an sp or sp2 hybridized carbon atom bonded to an sp3 hybridized carbon atom bonded to the oxygen atom bonded to the phosphorous atom, or at least one of R1 and R2 is an unsaturated inorganic group.

Abstract: Intercalation compositions having spinel structures with crystallites of metal oxides (M2O3) dispersed throughout the structure are provided having the general formula Li1+xMyMn2−x−yO4. Methods of producing the intercalation compositions and rechargeable lithium batteries containing the compositions are also provided.

Abstract: A negative electrode active material for a lithium-based secondary battery includes a graphite-like carbon material having an intensity ratio I(110)/I(002) of an X-ray diffraction peak intensity I(002) at a (002) plane to an X-ray diffraction peak intensity I(110) at a (110) plane of less than 0.2.

Abstract: Disclosed is carbonaceous material for a negative electrode of a lithium secondary battery and a lithium secondary battery made using the carbonaceous material. The carbonaceous material includes a silica film coated on a surface of carbon particles of the carbonaceous material, thereby minimizing both direct contact of the carbon particles with an organic electrolyte and cointercalation of the organic electrolyte and lithium ions within a structure of the carbon. The lithium secondary battery includes a negative electrode deposited with the carbonaceous material, a counterpart electrode made of lithium metal, electrolyte made of a propylene carbonate/ethylene carbonate solution containing 1 mol/l of LiPF8, and a polypropylene separator.

Abstract: This invention pertains to separators for electrochemical cells which comprise (i) a microporous pseudo-boehmite layer and (ii) a protective coating layer comprising a polymer; electrolyte elements comprising such separators; electrical current producing cells comprising such separators; and methods of making such separators, electrolyte elements and cells.

Abstract: This invention pertains to separators for electrochemical cells which comprise (i) two microporous pseudo-boehmite layers and (ii) a protective coating layer comprising a polymer interposed between the microporous pseudo-boehmite layers; electrolyte elements comprising such separators; electrical current producing cells comprising such separators; and methods of making such separators, electrolyte elements and cells.

Abstract: A small, portable electrochemical power cell, having an output voltage of over 4 V, and preferably over 5 V, includes an anode, a cathode comprising a fluorine compound and an electrolyte to maintain ionic conductivity between the anode and the cathode. A method of fabricating such an electrochemical power cell includes the step of adding a fluorine compound to the cathode and/or to the electrolyte solvent.

Abstract: A method for producing an active anode substance includes: a step for preparing, with mesophase carbon as a starting material, two carbon materials different in calcination temperature; a step for combining the two carbon materials at a specified ratio, turning the mixture into particles, and molding them into a shaped body; and a step for sintering the shaped body in an atmosphere of an inert gas or in a vacuum into a sintered anode body.