Patents by Inventor Aisaku Nagai

Aisaku Nagai 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: 8574770
    Abstract: A non-aqueous battery comprising a positive electrode material capable of being doped with and liberating lithium, a negative electrode material capable of being doped with and liberating lithium, and a polymer electrolyte disposed between the positive and negative electrode materials. The polymer electrolyte is formed by mixing a vinylidene fluoride copolymer and a nonaqueous electrolytic solution with a solvent, followed by evaporation of the solvent, so as to retain a high proportion of the nonaqueous electrolytic solution, leading to high electroconductivity and excellent strength in this state. The vinylidene fluoride copolymer comprises 80 to 97 wt. % of vinylidene fluoride monomer units and 3 to 20 wt. % of units of at least one monomer copolymerizable with vinylidene fluoride monomer, and has an inherent viscosity of 1.7 to 7 dl/g, as measured at 30° C. in a solution at a concentration of 4 g of polymer in 1 liter of N,N-dimethylformamide.
    Type: Grant
    Filed: September 21, 2011
    Date of Patent: November 5, 2013
    Assignee: Kureha Corporation
    Inventors: Takumi Katsurao, Katsuo Horie, Yukio Ichikawa, Aisaku Nagai
  • Publication number: 20120009482
    Abstract: A nonaqueous battery, such as a lithium ion battery, is formed from a polymer electrolyte comprising: a vinylidene fluoride copolymer comprises 90 to 97 wt. % of vinylidene fluoride monomer units and 3 to 10 wt. % of units of at least one monomer copolymerizable with the vinylidene fluoride monomer and has an inherent viscosity of 1.5 to 10 dl/g. The polymer electrolyte stably retains the nonaqueous electrolytic solution in a large amount and has excellent strength in this state.
    Type: Application
    Filed: September 21, 2011
    Publication date: January 12, 2012
    Inventors: Takumi Katsurao, Katsuo Horie, Yukio Ichikawa, Aisaku Nagai
  • Patent number: 8043386
    Abstract: A process for producing a polymer electrolyte for a nonaqueous battery by mixing a vinylidene fluoride copolymer and a nonaqueous electrolytic solution with a solvent that can be evaporated, wherein the vinylidene fluoride copolymer comprises 80 to 97 wt. % of vinylidene fluoride monomer units and 3 to 20 wt % of units of at least one monomer copolymerizable with vinylidene fluoride monomer and has an inherent viscosity of 1.5 to 10 dl/g, and evaporating the solvent to form a polymer electrolyte comprising the vinylidene fluoride copolymer impregnated with the nonaqueous electrolytic solution.
    Type: Grant
    Filed: October 14, 2008
    Date of Patent: October 25, 2011
    Assignee: Kureha Corporation
    Inventors: Takumi Katsurao, Katsuo Horie, Yukio Ichikawa, Aisaku Nagai
  • Patent number: 7858239
    Abstract: A negative electrode material for non-aqueous electrolyte secondary batteries, which is best suited for large current I/O non-aqueous electrolyte secondary batteries represented by those for hybrid electric vehicles (HEVs), which are unlikely to be influenced by the deterioration of battery characteristics due to water, and a production process thereof are provided. The negative electrode material having at least one exothermic peak in the range of not lower than 650° C. and lower than 700° C., and at least one exothermic peak in the range of not lower than 700° C. and lower than 760° C., in differential thermal analysis measured under an air flow.
    Type: Grant
    Filed: September 5, 2006
    Date of Patent: December 28, 2010
    Assignee: Kureha Corporation
    Inventors: Kazuhiko Shimizu, Aisaku Nagai
  • Patent number: 7851084
    Abstract: A core/shell polymer (A), comprising: a rubbery core comprising a crosslinked vinylidene fluoride copolymer (a) having a vinylidene fluoride content of 30-90 wt. % and a shell comprising a vinylidene fluoride polymer (b) having a vinylidene fluoride content which is larger than in the crosslinked vinylidene fluoride copolymer (a) and at least 80 wt. %, in a weight ratio (a)/(b) of 30/70-90/10. The vinylidene fluoride-based core/shell polymer (A) is excellent in mechanical properties including flexibility and resistance to nonaqueous electrolytic solutions, is capable of forming a composite electrode layer showing excellent flexibility and adhesion to an electroconductive substrate in combination with a powder active substance and is therefore suitable for use as a binder for nonaqueous electrochemical devices.
    Type: Grant
    Filed: January 20, 2006
    Date of Patent: December 14, 2010
    Assignee: Kureha Corporation
    Inventors: Mitsuyasu Sakuma, Tamito Igarashi, Aisaku Nagai, Nobuo Ahiko, Mayumi Sugahara
  • Patent number: 7718307
    Abstract: A negative electrode material for a high input/output currant-type non-aqueous electrolyte secondary battery, comprising a carbon material having an average (002) interlayer spacing d002 of 0.355-0.400 nm determined by X-ray diffractometry and a true density of 1.50-1.60 g/cm3, and exhibiting a capacity (A) of at least 50 mAh/g in a battery voltage range of 0.3-1.0 V and a ratio ((A)/(B)) of at least 0.3 between the capacity (A) and a capacity (B) in a battery voltage range of 0-1.0 V when measured as discharge capacities with a counter electrode of lithium. The negative electrode material is non-graphitizable and has properties suitable for a negative electrode material for high input/output current non-aqueous electrolyte secondary batteries as used in HEV, etc.
    Type: Grant
    Filed: March 29, 2005
    Date of Patent: May 18, 2010
    Assignee: Kureha Corporation
    Inventors: Kazuhiko Shimizu, Mariko Maeda, Syuji Morinishi, Aisaku Nagai, Akiko Hoshi
  • Publication number: 20090297953
    Abstract: A negative electrode material for non-aqueous electrolyte secondary batteries, which is best suited for large current I/O non-aqueous electrolyte secondary batteries represented by those for hybrid electric vehicles (HEVs), which are unlikely to be influenced by the deterioration of battery characteristics due to water, and a production process thereof are provided. The negative electrode material having at least one exothermic peak in the range of not lower than 650° C. and lower than 700° C., and at least one exothermic peak in the range of not lower than 700° C. and lower than 760° C., in differential thermal analysis measured under an air flow.
    Type: Application
    Filed: September 5, 2006
    Publication date: December 3, 2009
    Applicant: Kureha Corporation
    Inventors: Kazuhiko Shimizu, Aisaku Nagai
  • Publication number: 20090053610
    Abstract: A nonaqueous battery, such as a lithium ion battery, is formed from a polymer electrolyte comprising: a vinylidene fluoride copolymer comprises 90 to 97 wt. % of vinylidene fluoride monomer units and 3 to 10 wt. % of units of at least one monomer copolymerizable with the vinylidene fluoride monomer and has an inherent viscosity of 1.5 to 10 dl/g. The polymer electrolyte stably retains the nonaqueous electrolytic solution in a large amount and has excellent strength in this state.
    Type: Application
    Filed: October 14, 2008
    Publication date: February 26, 2009
    Inventors: Takumi Katsurao, Katsuo Horie, Yukio Ichikawa, Aisaku Nagai
  • Patent number: 7452387
    Abstract: A process for producing a polymer electrolyte for a nonaqueous battery by introducing 80 to 97 wt. % of vinylidene fluoride monomer and 3 to 20 wt % of at least one monomer copolymerizable with vinylidene fluoride monomer simultaneously all at once into a polymerization vessel, polymerizing the monomers to provide a vinylidene fluoride copolymer having polymerized units of the monomers and having an inherent viscosity of 1.5 to 10 dl/g, and impregnating the vinylidene fluoride copolymer with a nonaqueous electrolytic solution to provide a polymer electrolyte.
    Type: Grant
    Filed: May 19, 2004
    Date of Patent: November 18, 2008
    Assignee: Kureha Corporation
    Inventors: Takumi Katsurao, Katsuo Horie, Yukio Ichikawa, Aisaku Nagai
  • Publication number: 20080131776
    Abstract: A core/shell polymer (A), comprising: a rubbery core comprising a crosslinked vinylidene fluoride copolymer (a) having a vinylidene fluoride content of 30-90 wt. % and a shell comprising a vinylidene fluoride polymer (b) having a vinylidene fluoride content which is larger than in the crosslinked vinylidene fluoride copolymer (a) and at least 80 wt. %, in a weight ratio (a)/(b) of 30/70-90/10. The vinylidene fluoride-based core/shell polymer (A) is excellent in mechanical properties including flexibility and resistance to nonaqueous electrolytic solutions, is capable of forming a composite electrode layer showing excellent flexibility and adhesion to an electroconductive substrate in combination with a powder active substance and is therefore suitable for use as a binder for nonaqueous electrochemical devices.
    Type: Application
    Filed: January 20, 2006
    Publication date: June 5, 2008
    Inventors: Mitsuyasu Sakuma, Tamito Igarashi, Aisaku Nagai, Nobuo Ahiko, Mayumi Sugahara
  • Publication number: 20070287068
    Abstract: A negative electrode material for a high input/output currant-type non-aqueous electrolyte secondary battery, comprising a carbon material having an average (002) interlayer spacing d002 of 0.355-0.400 nm determined by X-ray diffractometry and a true density of 1.50-1.60 g/cm3, and exhibiting a capacity (A) of at least 50 mAh/g in a battery voltage range of 0.3-1.0 V and a ratio ((A)/(B)) of at least 0.3 between the capacity (A) and a capacity (B) in a battery voltage range of 0-1.0 V when measured as discharge capacities with a counter electrode of lithium. The negative electrode material is non-graphitizable and has properties suitable for a negative electrode material for high input/output current non-aqueous electrolyte secondary batteries as used in HEV, etc.
    Type: Application
    Filed: March 29, 2005
    Publication date: December 13, 2007
    Applicant: KUREHA CORPORATION
    Inventors: Kazuhiko Shimizu, Mariko Maeda, Syuji Morinishi, Aisaku Nagai, Akiko Hoshi
  • Patent number: 6921609
    Abstract: A composition suitable for use as a cathode material of a lithium battery includes a core material having an empirical formula LixM?zNi1?yM?yO2. “x” is equal to or greater than about 0.1 and equal to or less than about 1.3. “y” is greater than about 0.0 and equal to or less than about 0.5. “z” is greater than about 0.0 and equal to or less than about 0.2. M? is at least one member of the group consisting of sodium, potassium, nickel, calcium, magnesium and strontium. M? is at least one member of the group consisting of cobalt, iron, manganese, chromium, vanadium, titanium, magnesium, silicon, boron, aluminum and gallium. A coating on the core has a greater ratio of cobalt to nickel than the core. The coating and, optionally, the core can be a material having an empirical formula Lix1Ax2Ni1?y1?z1Coy1Bz1Oa. “x1” is greater than about 0.1 a equal to or less than about 1.3. “x2,” “y1” and “z1” each is greater than about 0.0 and equal to or less than about 0.2. “a” is greater than 1.5 and less than about 2.1.
    Type: Grant
    Filed: February 11, 2002
    Date of Patent: July 26, 2005
    Assignee: Kureha Chemical Industry Co., Ltd.
    Inventors: Christina Lampe-Onnerud, Per Onnerud, Jie Shi, Sharon Dalton, Tomoyoshi Koizumi, Aisaku Nagai
  • Patent number: 6855461
    Abstract: A crystal which can be employed as the active material of a lithium-based battery has an empirical formula of Lix1A2Ni1-y-zCoyBzOa, wherein “x1” is greater than about 0.1 and equal to or less than about 1.3, “x2,” “y” and “z” each is greater than about 0.0 and equal to or less than about 0.2, “a” is greater than about 1.5 and less than about 2.1, “A” is at least one element selected from the group consisting of barium, magnesium, calcium and strontium and “B” is at least one element selected from the group consisting of boron, aluminum, gallium, manganese, titanium, vanadium and zirconium.
    Type: Grant
    Filed: February 11, 2002
    Date of Patent: February 15, 2005
    Assignee: Kureha Chemical Industry Co., Ltd.
    Inventors: Christina Lampe-Onnerud, Per Onnerud, Dmitri Novikov, Jie Shi, Richard Chamberlain, Tomoyoshi Koizumi, Aisaku Nagai
  • Patent number: 6824927
    Abstract: A nonaqueous battery, such as a lithium ion battery, is formed from a polymer electrolyte comprising: a vinylidene fluoride copolymer comprises 80 to 97 wt. % of vinylidene fluoride monomer units and 3 to 20 wt. % of units of at least one monomer copolymerizable with the vinylidene fluoride monomer and has an inherent viscosity of 1.5 to 10 dl/g. The polymer electrolyte stably retains the nonaqueous electrolytic solution in a large amount and has excellent strength in this state.
    Type: Grant
    Filed: June 26, 2000
    Date of Patent: November 30, 2004
    Assignee: Kureha Kagaku Kogyo Kabushiki Kaisha
    Inventors: Takumi Katsurao, Katsuo Horie, Yukio Ichikawa, Aisaku Nagai
  • Publication number: 20040209168
    Abstract: A nonaqueous battery, such as a lithium ion battery, is formed from a polymer electrolyte comprising: a vinylidene fluoride copolymer comprises 90 to 97 wt. % of vinylidene fluoride monomer units and 3 to 10 wt. % of units of at least one monomer copolymerizable with the vinylidene fluoride monomer and has an inherent viscosity of 1.5 to 10 dl/g. The polymer electrolyte stably retains the nonaqueous electrolytic solution in a large amount and has excellent strength in this state.
    Type: Application
    Filed: May 19, 2004
    Publication date: October 21, 2004
    Inventors: Takumi Katsurao, Katsuo Horie, Yukio Ichikawa, Aisaku Nagai
  • Patent number: 6686427
    Abstract: A vinylidene fluoride polymer having good high-temperature coloring resistance is produced through suspension polymerization at 10-100° C. in a mixture solvent of 100 wt. parts of an aqueous medium and 10-50 wt. parts of a halogenated hydrocarbon solvent showing a good dissolving power to both a vinylidene fluoride monomer and a polymerization initiator and represented by a formula of: CX3CX2CHX2, wherein X is a fluorine or chlorine atom, and 7 X's include 4-6 fluorine atoms and 1-3 chlorine atoms. The vinylidene fluoride polymer is characterized by an elutable total organic carbon content in pure water at 95° C. of at most 1.1 &mgr;g/cm2.
    Type: Grant
    Filed: January 25, 2002
    Date of Patent: February 3, 2004
    Assignee: Kureha Chemical Industry Company, Limited
    Inventors: Takumi Katsurao, Toshio Hosokawa, Katsuo Horie, Yoshikichi Teramoto, Aisaku Nagai
  • Publication number: 20020192556
    Abstract: A crystal which can be employed as the active material of a lithium-based battery has an empirical formula of Lix1A2Ni1−y−zCoyBzOa, wherein “x1” is greater than about 0.1 and equal to or less than about 1.3, “x2,” “y” and “z” each is greater than about 0.0 and equal to or less than about 0.2, “a” is greater than about 1.5 and less than about 2.1, “A” is at least one element selected from the group consisting of barium, magnesium, calcium and strontium and “B” is at least one element selected from the group consisting of boron, aluminum, gallium, manganese, titanium, vanadium and zirconium.
    Type: Application
    Filed: February 11, 2002
    Publication date: December 19, 2002
    Applicant: Kureha Chemical Industry Co., Ltd.
    Inventors: Christina Lampe-Onnerud, Per Onnerud, Dmitri Novikov, Jie Shi, Richard V. Chamberlain, Tomoyoshi Koizumi, Aisaku Nagai
  • Publication number: 20020192552
    Abstract: A composition suitable for use as a cathode material of a lithium battery includes a core material having an empirical formula LixM′zNi1−yM″yO2. “x” is equal to or greater than about 0.1 and equal to or less than about 1.3. “y” is greater than about 0.0 and equal to or less than about 0.5. “z” is greater than about 0.0 and equal to or less than about 0.2. M′ is at least one member of the group consisting of sodium, potassium, nickel, calcium, magnesium and strontium. M″ is at least one member of the group consisting of cobalt, iron, manganese, chromium, vanadium, titanium, magnesium, silicon, boron, aluminum and gallium. A coating on the core has a greater ratio of cobalt to nickel than the core. The coating and, optionally, the core can be a material having an empirical formula Lix1Ax2Ni1−y1−z1Coy1Bz1Oa. “x1” is greater than about 0.1 and equal to or less than about 1.3.
    Type: Application
    Filed: February 11, 2002
    Publication date: December 19, 2002
    Applicant: Kureha Chemical Industry Co., Ltd.
    Inventors: Christina Lampe-Onnerud, Per Onnerud, Jie Shi, Sharon Dalton, Tomoyoshi Koizumi, Aisaku Nagai
  • Publication number: 20020143103
    Abstract: A vinylidene fluoride polymer having good high-temperature coloring resistance is produced through suspension polymerization at 10-100° C. in a mixture solvent of 100 wt. parts of an aqueous medium and 10-50 wt.
    Type: Application
    Filed: January 25, 2002
    Publication date: October 3, 2002
    Inventors: Takumi Katsurao, Toshio Hosokawa, Katsuo Horie, Yoshikichi Teramoto, Aisaku Nagai
  • Patent number: 6372388
    Abstract: A solid polymer electrolyte having improved ionic conductivity and adhesion with an electroconductive substrate and also remarkably enhanced heat resistance is formed with a vinylidene fluoride copolymer which contains 50-97 mol. % of vinylidene fluoride monomer and 0.1-5 mol. % of an unsaturated dibasic acid monoester or an epoxy group-containing vinyl monomer and further has been crosslinked, thereby improving the performances of a non-aqueous battery, such as a lithium ion battery.
    Type: Grant
    Filed: January 24, 2000
    Date of Patent: April 16, 2002
    Assignee: Kureha Kaguka Kogyo Kabushiki Kaisha
    Inventors: Takumi Katsurao, Katsuo Horie, Aisaku Nagai, Yukio Ichikawa