And Alkali Metal Or Alkaline Earth Metal Containing Patents (Class 423/594.2)
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Patent number: 7011898Abstract: A method of forming a composite structure includes: (1) providing first and second sintered bodies containing first and second multicomponent metallic oxides having first and second identical crystal structures that are perovskitic or fluoritic; (2) providing a joint material containing at least one metal oxide: (a) containing (i) at least one metal of an identical IUPAC Group as at least one sintered body metal in one of the multicomponent metallic oxides, (ii) a first row D-Block transition metal not contained in the multicomponent metallic oxides, and/or (iii) a lanthanide not contained in the multicomponent metallic oxides; (b) free of metals contained in the multicomponent metallic oxides; (c) free of cations of boron, silicon, germanium, tin, lead, arsenic, antimony, phosphorus and tellurium; and (d) having a melting point below the sintering temperatures of the sintered bodies; and (3) heating to a joining temperature above the melting point and below the sintering temperatures.Type: GrantFiled: March 21, 2003Date of Patent: March 14, 2006Assignee: Air Products and Chemicals, Inc.Inventors: Darryl Paul Butt, Raymond Ashton Cutler, Steven Walton Rynders, Michael Francis Carolan
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Patent number: 6986879Abstract: A complex metal oxide powder composed of fine particles, each in an approximately spherical shape, is provided by a method for producing a complex metal oxide powder, which method comprises heating at least two kinds of metal salts, or a complex metal salt comprising at least two kinds of metals, to a temperature at which transition to a complex metal oxide occurs, and calcining the metal salts or the complex metal salt in an atmosphere containing a halogenated hydrogen gas.Type: GrantFiled: October 15, 2001Date of Patent: January 17, 2006Assignee: Sumitomo Chemical Company, LimitedInventor: Yoshio Uchida
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Patent number: 6926912Abstract: A non-aluminum containing mixed metal compound for pharmaceutical use, which may, for example, be a mixed metal hydroxy carbonate containing magnesium and iron, and may have a hydrotalcite structure, preferably a non-aged hydrotalcite structure. Other metals, including, for example, calcium, lanthanum and cerium, may also be used. Metal sulphate compounds, especially calcium sulphate, lanthanum sulphate and/or cerium sulphate, compounds are also useful. The mixed metal compounds have a phosphate binding capacity of at least 30%, by weight, based on the test methods 1, 2 or 3, described in the specification, over a pH range from 3 to 7, such as from 2 to 8. The compound is especially useful in the treatment of hyperphosphataemia.Type: GrantFiled: September 18, 1998Date of Patent: August 9, 2005Assignee: Ineos Silicas LimitedInventors: Norman B Roberts, Maurice Webb, Benjamin J Rankin
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Patent number: 6913855Abstract: A method for making an active material comprises the steps of forming a slurry, spray drying the slurry to form a powdered precursor composition, and heating the powdered precursor composition at a temperature and for a time sufficient to form a reaction product. The slurry has a liquid phase and a solid phase, and contains at least an alkali metal compound and a transition metal compound. Preferably the liquid phase contains dissolved alkali metal compound, and the solid phase contains an insoluble transition metal compound, an insoluble carbonaceous material compound, or both. Electrodes and batteries are provided that contain the active materials.Type: GrantFiled: July 22, 2002Date of Patent: July 5, 2005Assignee: Valence Technology, Inc.Inventors: Johnnie Stoker, James Hodge
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Patent number: 6890500Abstract: The invention is directed to open-framework and microporous solids well suited for use in catalysis and ion exchange. The microporous solids are constructed by using a salt template which can be readily removed without destroying the framework of the micropore. Various microporous solids can be formed having different geometric structures depending upon the templating salt used and the concentration. Examples of two compounds include Na2Cs[Mn3(P2O7)2]Cl and K2.02Cs2.90[Cu3(P2O7)2]Cl2.92. Both compounds have 3-D (Mn, Cu)—P—O frameworks.Type: GrantFiled: January 12, 2004Date of Patent: May 10, 2005Assignee: Clemson UniversityInventors: Shiou-Jyh Hwu, Qun Huang, Mutlu Ulutagay
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Patent number: 6878490Abstract: The present invention is a positive electrode active material that can be used in secondary lithium and lithium-ion batteries to provide the power capability, i.e., the ability to deliver or retake energy in short periods of time, desired for large power applications such as power tools, electric bikes and hybrid electric vehicles. The positive electrode active material of the invention includes at least one electron conducting compound of the formula LiM1x?y{A}yOz and at least one electron insulating and lithium ion conducting lithium metal oxide, wherein M1 is a transition metal, {A} is represented by the formula ?wiBi wherein Bi is an element other than M1 used to replace the transition metal M1 and wi is the fractional amount of element Bi in the total dopant combination such that ?wi=1; Bi is a cation in LiM1x?y{A}yOz; 0.95?x?2.10; 0?y?x/2; and 1.90?z?4.20.Type: GrantFiled: October 29, 2001Date of Patent: April 12, 2005Assignee: FMC CorporationInventors: Yuan Gao, Marina Yakovleva, Michael E. Leonowicz, Prakash Palepu, John F. Engel
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Patent number: 6875416Abstract: The invention relates to a method for producing lithium-transition metal mixtures of general formula Lix(M1yM21-y)nOnz, wherein M1 represents nickel, cobalt or manganese, M2 represents chromium, cobalt, iron, manganese, molybdenum or aluminium, and is different from M1, n is 2 if M1 represents manganese and is 1 otherwise, x is comprised between 0.9 and 1.2, y is comprised between 0.5 and 1.0 and z is comprised between 1.9 and 2.1. According to the inventive method, an intimate mixture composed of transition metal compounds containing oxygen and of a lithium compound containing oxygen is calcinated, said mixture being obtained by processing a solid powder transition metal compound with a solution of said lithium compound, and then drying. At least the M1 compound is used in powder form having a specific surface of at least 20 m2/g (BET) and calcination is carried out in a fluidised bed.Type: GrantFiled: August 13, 1998Date of Patent: April 5, 2005Assignee: H. C. Starck GmbH & CoInventors: Mathias Benz, Wolfgang Kummer, Evelyn Pross, Josef Schmoll, Wolfgang Schweda, Daniel Duff, Ricarda Leiberich, Christoph Schild, Ulrich Krynitz, Juliane Meese-Marktscheffel, Viktor Stoller
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Patent number: 6838072Abstract: The invention relates to a process for preparing lithium intercalation compounds by plasma reaction comprising the steps of: forming a feed solution by mixing lithium nitrate or lithium hydroxide or lithium oxide and the required metal nitrate or metal hydroxide or metal oxide and between 10-50% alcohol by weight; mixing the feed solution with O2 gas wherein the O2 gas atomizes the feed solution into fine reactant droplets, inserting the atomized feed solution into a plasma reactor to form an intercalation powder; and if desired, heating the resulting powder to from a very pure single phase product.Type: GrantFiled: October 2, 2002Date of Patent: January 4, 2005Assignee: The United States of America as represented by the United States Department of EnergyInventors: Peter C. Kong, Robert J. Pink, Lee O. Nelson
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Publication number: 20040265693Abstract: The positive electrode active material of the present invention is characterized in that its main component is a lithium metal oxide, and the lithium concentration at the surface portion of the primary particles that make up the active material is lower than that in the interior thereof. There will be less increase in internal resistance with a secondary cell made using this active material. The above-mentioned active material can be manufactured, for example, by bringing the raw active material into contact with a treatment liquid containing metal ions, and thereby lowering the lithium concentration at the surface portion of the primary particles that make up the raw active material.Type: ApplicationFiled: June 17, 2004Publication date: December 30, 2004Applicant: Toyota Jidosha Kabushiki KaishaInventor: Saeko Kurachi
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Patent number: 6835367Abstract: The present invention relates to a single step process for the synthesis of nanoparticles of phase pure ceramic oxides of a single or a multi-component system comprising one or more metal ions. The process comprises preparing a solution containing all the required metal ions in stoichiometric ratio by dissolving their respective soluble salts in an organic solvent or in water, preparing a precursor, adjusting the nitrate/ammonia content in the system, and heating the system.Type: GrantFiled: February 28, 2002Date of Patent: December 28, 2004Assignee: Council of Scientific and Industrial ResearchInventors: Jose James, Rajan Jose, Asha Mary John, Jacob Koshy
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Publication number: 20040253171Abstract: A method of synthesis of alkali metal ferrates and alkaline earth metal ferrates, in which a trivalent iron compound is mixed with potash and optionally persulphate, and the mixture is heated at a temperature in the range of about 250 to about 500° C. for about 1 to 10 hours. The invention also relates to the use of the ferrates obtained by this method.Type: ApplicationFiled: June 10, 2004Publication date: December 16, 2004Applicant: InertecInventors: Jean-Yves Cojan, David Verschuere, Farouk Tedjar
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Publication number: 20040242413Abstract: A porous catalyst layer containing mixed conducting oxide is contiguous to a second surface (1a) of a selective oxygen-permeable dense continuous layer (1) containing mixed conducting oxide. A porous intermediate catalyst layer (3) containing mixed conducting oxide is contiguous to a first layer (1b) of the dense continuous layer (1). A porous reactive catalyst layer (4) provided with a metal catalyst and a support is contiguous to the porous intermediate catalyst layer (3) in a manner to sandwich between the dense continuous layer (1) and the porous reactive catalyst layer (4).Type: ApplicationFiled: April 14, 2004Publication date: December 2, 2004Inventors: Tadashi Sakon, Wataru Ito, Hitoshi Dohnomae, Toru Nagai, Hideki Kurimura, Shouichi Kaganoi, Youhei Suzuki, Takashi Ito
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Publication number: 20040191161Abstract: This invention discloses compounds of lithium nickel cobalt metal oxide and the methods of their fabrication. The formula for said compounds of lithium nickel metal of oxide is LiaNi1-b-cCobMcO2 where 0.97≦a≦1.05 , 0.01≦b≦0.30 , 0≦c≦0.10, and M is one or more or the following: manganese, aluminum, titanium, chromium, magnesium, calcium, vanadium, iron, and zirconium.Type: ApplicationFiled: April 14, 2004Publication date: September 30, 2004Inventors: Chuanfu Wang, Zhanfeng Jiang, Huiquan Liu, Junqing Dong
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Publication number: 20040191628Abstract: As a positive electrode active material, a lithium transition metal complex oxide having a layered rock-salt structure containing lithium (Li) and containing magnesium atoms (Mg) substituted for part of lithium atoms (Li) is used. The lithium transition metal complex oxide is formed by chemical or electrochemical substitution of Mg atoms for part of Li atoms in LiCoO2, LiMnO2, LiFeO2, LiNiO2, or the like. A cell is prepared in which a negative electrode 2 and a positive electrode 1 including the lithium transition metal complex oxide (positive electrode active material) are disposed in a non-aqueous electrolyte 5 including a lithium salt, and part of Li in the lithium transition metal complex oxide is extracted by discharging the cell. Then, the electrolyte including Li is replaced with an electrolyte including Mg; and the cell is discharged, so that Mg atoms are substituted for the part of Li atoms in the lithium transition metal complex oxide.Type: ApplicationFiled: March 17, 2004Publication date: September 30, 2004Applicant: SANYO ELECTRIC CO., LTD.Inventors: Takao Inoue, Masahisa Fujimoto, Masaharu Itaya
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Patent number: 6793842Abstract: A ferrite fine powder having a mean particle size of 0.1 to 30 &mgr;m and made of spherical single-crystal particles. The ferrite fine powder has superior physical properties and excellent magnetic properties desirable for use as a raw material for a dust core of coils, transformers, etc. The powder is prepared by forming a solution or suspension containing a compound or compounds of at least one of the metals forming the ferrite into fine droplets, and thermally decomposing the droplets at elevated temperatures.Type: GrantFiled: July 6, 2001Date of Patent: September 21, 2004Assignees: Shoei Chemical Inc., TDK CorporationInventors: Yuji Akimoto, Kazuro Nagashima, Masahiro Ikemoto, Minoru Takaya, Yoshiaki Akachi, Hisashi Kobuke
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Patent number: 6790429Abstract: Novel methods and devices for synthesizing ferrate and uses thereof are described. One aspect of the invention relates to synthesizing ferrate at a site proximal to the site of use, another aspect of the invention relates to devices and methods for synthesizing ferrate.Type: GrantFiled: January 14, 2002Date of Patent: September 14, 2004Assignee: Ab Initio LCInventor: Lee Edward Ciampi
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Publication number: 20040175618Abstract: There is provided a lithium secondary battery having a high capacity and excellent high-rate discharge characteristic and charge/discharge cycle characteristic. The lithium secondary battery comprises a negative electrode, a positive electrode and an ionic conductor, wherein the positive electrode comprises lithium metal composite oxide particles; the lithium metal composite oxide particles comprise a plurality of secondary particles in an elongated shape each comprised of a plurality of primary particles with an average particle size of 0.1 to 1 &mgr;m so aggregated as to form a void therebetween; and the secondary particle is columnar or planar and has an average size in a long length direction of 5 to 15 &mgr;m.Type: ApplicationFiled: March 1, 2004Publication date: September 9, 2004Applicant: Canon Kabushiki KaishaInventors: Katsuhiko Inoue, Soichiro Kawakami
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Patent number: 6780394Abstract: A perovskite feedstock (powder or preform) is placed in a high-pressure cell of a high pressure/high temperature (HP/HT) apparatus and subjected to pressures in excess of about 2 kbar and temperatures above about 800° C. for a time adequate to increase the density of the preform.Type: GrantFiled: August 16, 2001Date of Patent: August 24, 2004Assignee: Diamond Innovations, Inc.Inventors: Suresh S. Vagarali, John W. Lucek
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Publication number: 20040151661Abstract: A method for making ferrite magnets of formula M1-xRxFe12-yTyO19 including: a1) forming a powder mixture MP of related raw materials, a2) transforming into granules in green state A, b) calcining the granules in green state to form clinker B, c) wet ding clinker B to obtain a homogeneous dispersion of fine particles C, d) concentrating and compressing the particles under an orienting magnetic field to form an anisotropic green compact D, and e) sintering the green compact to obtain a sintered element E. In step a1), MP is formed from a dry mixture MS of M and Fe powder elements and a dispersion DF of raw materials related to elements R and T, and in step b) the granules in green state are calcined to obtain a clinker B which is homogeneous in chemical composition and size and with apparent low density, between 2.5 and 3.5.Type: ApplicationFiled: January 26, 2004Publication date: August 5, 2004Applicant: UGIMAG, S.A.Inventors: Philippe Tenaud, Eric Brando
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Patent number: 6770256Abstract: Metal oxides having a perovskite or perovskite-like crystal structure are prepared by a process comprising subjecting a mixture of starring powders to a high energy milling sufficient to induce chemical reaction of the components and thereby directly mechanosynthesize said metal oxide in the form of a perovskite or a perovskite-like material having a nanocrystalline structure as determined by X-ray diffractometry. The process according to the present invention is simple, efficient, not expensive and does not require any heating step for producing a perovskite that may easily show a very high specific surface area. Another advantage is that the perovskite obtained according to the present invention also has a high density of lattice defects thereby showing a higher catalytic activity, a characteristic which is highly desirable in their eventual application as catalysts and electronic conductors.Type: GrantFiled: April 9, 2001Date of Patent: August 3, 2004Assignee: Universite LavalInventors: Serge Kaliaguine, André Van Neste
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Patent number: 6758894Abstract: A black pigment substantially free of objectionable transition metal materials is disclosed. This pigment is particularly useful for coloring glass since the absence of the transition metal gives it excellent recycling properties. The pigment is an alkaline earth (preferably strontium) iron maganese oxide material as specifically defined the in the present invention.Type: GrantFiled: April 17, 2003Date of Patent: July 6, 2004Assignee: The Shepherd Color CompanyInventor: Joel D. Houmes
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Publication number: 20040126300Abstract: The invention provides a novel method for making lithium mixed metal materials in electrochemical cells. The lithium mixed metal materials comprise lithium and at least one other metal besides lithium. The invention involves the reaction of a metal compound, a phosphate compound, with a reducing agent to reduce the metal and form a metal phosphate. The invention also includes methods of making lithium metal oxides involving reaction of a lithium compound, a metal oxide with a reducing agent.Type: ApplicationFiled: October 9, 2003Publication date: July 1, 2004Inventors: Jeremy Barker, M. Yazid Saidi, Jeffrey Swoyer
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Patent number: 6730281Abstract: A method for carrying out solid state reactions under reducing conditions is provided. Solid state reactants include at least one inorganic metal compound and a source of reducing carbon. The reaction may be carried out in a reducing atmosphere in the presence of reducing carbon. Reducing carbon may be supplied by elemental carbon, by an organic material, or by mixtures. The organic material is one that can form decomposition products containing carbon in a form capable of acting as a reductant. The reaction proceeds without significant covalent incorporation of organic material into the reaction product. In a preferred embodiment, the solid state reactants also include an alkali metal compound. The products of the method find use in lithium ion batteries as cathode active materials. Preferred active materials include lithium-transition metal phosphates and lithium-transition metal oxides.Type: GrantFiled: May 17, 2002Date of Patent: May 4, 2004Assignee: Valence Technology, Inc.Inventors: Jeremy Barker, M. Yazid Saidi, Jeffrey L. Swoyer, Ming Dong
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Patent number: 6719955Abstract: The invention is directed to open-framework and microporous solids well suited for use in catalysis and ion exchange. The microporous solids are constructed by using a salt template which can be readily removed without destroying the framework of the micropore. Various microporous solids can be formed having different geometric structures depending upon the templating salt used and the concentration. Examples of two compounds include Na2Cs[Mn3(P2O7)2]Cl and K2.02Cs2.90[Cu3(P2O7)2]Cl2.92. Both compounds have 3-D (Mn,Cu)—P—O frameworks.Type: GrantFiled: November 12, 1999Date of Patent: April 13, 2004Assignee: Clemson UniversityInventors: Shiou-Jyh Hwu, Qun Huang, Mutlu Ulutagay
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Patent number: 6713037Abstract: A process method for producing a lithium based mixed oxide of the formula LiM′x . . . Oy through the steps of combining a lithium oxide with a second oxide having the base metal element (M′) at room temperature; and applying to the combination, a high energy milling process, wherein the high energy milling process obtains, without the addition of substantial external heat being added to the synthesis, a chemical synthesis of a composite oxide of the above formula, having crystallites of nanometer dimension.Type: GrantFiled: September 30, 2002Date of Patent: March 30, 2004Assignee: Nanox, Inc.Inventor: Andre Van Neste
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Publication number: 20040057897Abstract: The room temperature, low field intergrain magnetoresistance (IMR) of the double perovsktite SrFe0.5MO0.5O3 is found to be highly tunable by doping either Ca or Ba into the Sr site. The dopant exerts a chemical pressure, changing the Curie temperature and the magnetic softness. The IMR at optimal doping (Sr0.2Ba0.8Fe0.5Mo0.5O3) is approximately 3.5% in 100 Oe, and increases further in high fields. The unprecedented strength of the IMR in this highly spin polarized system provides new grounds for employing novel magnetic materials for new magnetic sensing applications and spin electronics.Type: ApplicationFiled: March 7, 2003Publication date: March 25, 2004Inventors: Sang-Wook Cheong, Bog-Gi Kim
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Publication number: 20040016632Abstract: In a method for synthesizing reduced metal compounds using electromagnetic radiation, starting materials comprising at least one particulate metal compound and at least one source of carbon are combined to form a mixture. The mixture is exposed to electromagnetic radiation to form a reaction product. Preferably, the carbon is a reducing carbon, and at least one metal of the starting materials is reduced in oxidation state during radiation exposure. Reducing carbon may be supplied by elemental carbon, by an organic material, or by mixtures. Preferably, the solid state reactants also include an alkali metal compound. The products of the method are preferably useful as cathode active materials in lithium ion batteries. The electromagnetic radiation is selected from among microwave, infrared, and radio frequencies of about 1 MHz to 3000 GHz.Type: ApplicationFiled: July 26, 2002Publication date: January 29, 2004Inventor: Jeremy Barker
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Publication number: 20030235528Abstract: A method for producing a positive electrode material of Li-ion secondary batteries is disclosed.Type: ApplicationFiled: June 11, 2003Publication date: December 25, 2003Applicant: Tatung Co., Ltd.Inventors: She-Huang Wu, Yung-Jen Lin, Mu-Rong Yang, Wen-Jen Liu, Yi-Shiuan Chen
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Publication number: 20030235527Abstract: A method for producing a positive electrode material adapted to the Li-ion secondary batteries is disclosed.Type: ApplicationFiled: June 11, 2003Publication date: December 25, 2003Applicant: Tatung Co., Ltd.Inventors: She-Huang Wu, Yung-Jen Lin, Mu-Rong Yang, Wen-Jen Liu, Yi-Shiuan Chen
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Patent number: 6660242Abstract: A method is disclosed for the manufacture of particles composed of an intimate admixture of barium or strontium ferrite and ferric oxide from a chloride solution containing barium or strontium ions and ferrous ions by a pyrohydrolysis reaction. The presence of carbon dioxide in the heated atmosphere in which pyrohydrolysis of an admixture of alkaline earth metal chloride and iron chloride is carried out has been discovered to substantially decrease the temperature required for reaction to occur.Type: GrantFiled: December 28, 2001Date of Patent: December 9, 2003Inventors: Lloyd Ballard Mauldin, Jerry Allen Cook
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Patent number: 6652780Abstract: A process for oxidizing iron ions contained within iron-doped lithium niobate. The process comprises the steps of protonating the iron-doped lithium niobate crystal and then placing the same into a pressure chamber where between 10-100 atmospheres of dry, ultra-pure pressurized oxygen are applied. While under pressure, the crystal is heated to approximately 950° C. at a rate not to exceed 50° C. per minute, and preferably at a rate not less than 25° C. per minute. The resulting lithium niobate crystal will thereafter contain iron ions wherein the divalent iron ion ratio to the trivalent iron ion ratio is approximately 1:100.Type: GrantFiled: March 6, 2002Date of Patent: November 25, 2003Assignee: Northrop GrummanInventor: Harold M Stoll
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Publication number: 20030180616Abstract: Lithium metal oxide compounds of nominal formula Li2MO2, in which M represents two or more positively charged metal ions, selected predominantly and preferably from the first row of transition metals are disclosed herein. The Li2MO2 compounds have a layered-type structure, which can be used as positive electrodes for lithium electrochemical cells, or as a precursor for the in-situ electrochemical fabrication of LiMO2 electrodes. The Li2MO2 compounds of the invention may have additional functions in lithium cells, for example, as end-of-discharge indicators, or as negative electrodes for lithium cells.Type: ApplicationFiled: February 12, 2003Publication date: September 25, 2003Applicant: The University of ChicagoInventors: Christopher S. Johnson, Michael M. Thackeray, John T. Vaughey, Arthur J. Kahaian, Jeom-Soo Kim
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Publication number: 20030170540Abstract: The present invention provides a high-capacity and low-cost non-aqueous electrolyte secondary battery, comprising: a negative electrode containing, as a negative electrode active material, a ssubstance capable of absorbing/desorbing lithium ions and/or metal lithium; a separator; a positive electrode; and an electrolyte, wherein the positive electrode active material contained in the positive electrode is composed of crystalline particles of an oxide containing two kinds of transition metal elements, the crystalline particles having a layered crystal structure, and oxygen atoms constituting the oxide forming a cubic closest packing structure.Type: ApplicationFiled: January 17, 2003Publication date: September 11, 2003Inventors: Tsutomu Ohzuku, Hiroshi Yoshizawa, Masatoshi Nagayama
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Patent number: 6599493Abstract: The present invention is directed to methods for preparing hydrous iron oxide spherules, hydrous iron oxide gels such as gel slabs, films, capillary and electrophoresis gels, iron monohydrogen phosphate spherules, hydrous iron oxide spherules having suspendable particles homogeneously embedded within to form composite sorbents and catalysts, iron monohydrogen phosphate spherules having suspendable particles of at least one different sorbent homogeneously embedded within to form a composite sorbent, iron oxide spherules having suspendable particles homogeneously embedded within to form a composite of hydrous iron oxide fiber materials, iron oxide fiber materials, hydrous iron oxide fiber materials having suspendable particles homogeneously embedded within to form a composite, iron oxide fiber materials having suspendable particles homogeneously embedded within to form a composite, dielectric spherules of barium, strontium, and lead ferrites and mixtures thereof, and composite catalytic spherules of barium or sType: GrantFiled: July 27, 2001Date of Patent: July 29, 2003Assignee: UT-Battelle, LLCInventors: Jack L. Collins, Robert J. Lauf, Kimberly K. Anderson
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Patent number: 6592841Abstract: A method of treating a hollandite compound to improve its adsorption of nitrogen monoxide, which comprises subjecting a hollandite compound having a hollandite-type crystal structure and represented by a chemical formula AxMyN8-yO16, wherein A is an alkali metal or an alkaline earth metal K, Na, Rb or Ca, M is a bivalent or trivalent metal element Fe, Ga, Zn, In, Cr, Co, Mg, Al or Ni, N is a tetravalent metal element Sn or Ti, 0<x≦2 and 0<y≦2, to a heat treatment in a stream of an oxygen-nitrogen mixture having oxygen gas and nitrogen gas mixed in a volume ratio of 3:97 to 50:50, at a temperature of from 50 to 1,500° C. for from 5 minutes to 1 hour.Type: GrantFiled: March 5, 2001Date of Patent: July 15, 2003Assignee: National Institute for Research in Inorganic MaterialsInventors: Kenjiro Fujimoto, Jun Suzuki, Toshiyuki Mori, Mamoru Watanabe
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Publication number: 20030124052Abstract: A method is disclosed for the manufacture of barium or strontium ferrite from a chloride solution containing barium or strontium ions and ferrous ions by a pyrohydrolysis reaction catalyzed by carbon dioxide. The presence of carbon dioxide in the heated atmosphere in which pyrohydrolysis of an admixture of alkaline earth metal chloride and iron chloride is carried out substantially decreases the temperature required for reaction to occur.Type: ApplicationFiled: December 28, 2001Publication date: July 3, 2003Inventors: Lloyd Ballard Mauldin, Jerry Allen Cook