Patents by Inventor Eri Kojima

Eri Kojima 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: 9673446
    Abstract: A lithium ion secondary battery containing a negative electrode active material containing Si and O as constituent elements and exhibiting excellent charge-discharge cycle characteristics. The lithium ion secondary battery has a positive electrode having a positive electrode material mixture layer, a negative electrode, a separator and a nonaqueous electrolyte containing at least an electrolyte salt and an organic solvent, where the negative electrode has a negative electrode material mixture layer containing a negative electrode active material containing Si and O as constituent elements (the atomic ratio x of O to Si is 0.5?x?1.5). The nonaqueous electrolyte contains the electrolyte salt at a concentration exceeding a concentration at which conductivity in the nonaqueous electrolyte containing the electrolyte salt and the organic solvent is maximized, and the conductivity at 25° C. is 6.5 to 16 mS/cm.
    Type: Grant
    Filed: February 28, 2012
    Date of Patent: June 6, 2017
    Assignee: HITACHI MAXELL, LTD.
    Inventors: Eri Kojima, Takahiro Furutani, Mitsuhiro Kishimi
  • Patent number: 9166250
    Abstract: The separator for a battery according to the present invention is a separator for a battery including an insulator layer containing a fibrous material having a heat resistant temperature of equal to or higher than 150° C., insulating inorganic fine particles and a binder, or a separator for a battery including a porous layer formed of a thermal melting resin and an insulator layer containing insulating inorganic fine particles and a binder, wherein water content per unit volume is equal to or smaller than 1 mg/cm3 when the separator is held for 24 hours in an atmosphere with a relative humidity of 60% at 20° C. The use of the separator for a battery according to the present invention makes it possible to provide a lithium secondary battery that has favorable reliability and safety and is excellent in storage characteristics and charge-discharge cycle characteristics.
    Type: Grant
    Filed: September 7, 2007
    Date of Patent: October 20, 2015
    Assignee: HITACHI MAXELL, LTD.
    Inventors: Hideaki Katayama, Eri Kojima, Shigeo Aoyama, Yoshinori Sato
  • Patent number: 8999586
    Abstract: The present invention relates to an electrode for a non-aqueous electrolyte secondary battery, a non-aqueous electrolyte secondary battery using the electrode, and a method for manufacturing the non-aqueous electrolyte secondary battery. The electrode for a non-aqueous electrolyte secondary battery includes a material mixture layer containing an active material and a porous insulating layer. The insulating layer is formed on the material mixture layer. The insulating layer contains a resin having a cross-linked structure and inorganic particles. A mixed layer that includes components of the insulating layer and components of the material mixture layer is provided at the interface between the insulating layer and the material mixture layer.
    Type: Grant
    Filed: February 27, 2013
    Date of Patent: April 7, 2015
    Assignee: Hitachi, Ltd.
    Inventors: Toshiyuki Watanabe, Kunihiko Koyama, Takahiro Furutani, Eri Kojima
  • Patent number: 8852818
    Abstract: A non-aqueous secondary battery contains a positive electrode, a negative electrode, a separator and a non-aqueous electrolytic solution. The positive electrode contains a layered structure lithium-containing compound oxide, or a spinel lithium-containing compound oxide containing manganese as an active material. The non-aqueous electrolytic solution contains at least one additive selected from a sulfonic acid anhydride, a sulfonate ester derivative, a cyclic sulfate derivative and a cyclic sulfonate ester derivative, and a vinylene carbonate or a derivative of the vinylene carbonate.
    Type: Grant
    Filed: June 6, 2011
    Date of Patent: October 7, 2014
    Assignee: Hitachi Maxell, Ltd.
    Inventors: Jinbao Zhao, Eri Kojima
  • Publication number: 20140186682
    Abstract: A non-aqueous electrolyte secondary battery of the present invention includes a positive electrode, a negative electrode, and a non-aqueous electrolyte. An insulating layer is provided between the positive electrode and the negative electrode. The insulating layer contains at least one type of hydrogen carbonate selected from a sodium hydrogen carbonate and a potassium hydrogen carbonate. The hydrogen carbonate has an average particle size of 2 to 20 ?m. A content of the hydrogen carbonate is 5 to 80 vol % of the total volume of the insulating layer. The insulating layer has a thickness of 4 to 40 ?m.
    Type: Application
    Filed: March 13, 2012
    Publication date: July 3, 2014
    Applicant: HITACHI, LTD.
    Inventors: Kunihiko Koyama, Toshiyuki Watanabe, Takahiro Furutani, Eri Kojima, Masato Harigae
  • Publication number: 20140030606
    Abstract: The method for producing a separator for an electrochemical device of the present invention includes: obtaining a separator forming composition, wherein the separator forming composition contains a resin raw material including a monomer or an oligomer, a solvent (a) capable of dissolving the resin raw material; and a solvent (b) capable of causing the resin raw material to agglomerate by solvent shock, and Vsb/Vsa as a ratio between the volume Vsa of the solvent (a) and the volume Vsb of the solvent (b) is 0.04 to 0.2; applying the composition to a substrate; irradiating with energy rays a coating of the applied composition to form a resin (A) having a crosslinked structure; and drying the coating after the formation of the resin (A) to form pores. The separator for an electrochemical device of the present invention is produced by the production method of the present invention.
    Type: Application
    Filed: March 12, 2012
    Publication date: January 30, 2014
    Applicant: HITACHI, LTD.
    Inventors: Eri Kojima, Takahiro Furutani, Toshiyuki Watanabe, Kunihiko Koyama
  • Publication number: 20130244116
    Abstract: The present invention relates to an electrode for a non-aqueous electrolyte secondary battery, a non-aqueous electrolyte secondary battery using the electrode, and a method for manufacturing the non-aqueous electrolyte secondary battery. The electrode for a non-aqueous electrolyte secondary battery includes a material mixture layer containing an active material and a porous insulating layer. The insulating layer is formed on the material mixture layer. The insulating layer contains a resin having a cross-linked structure and inorganic particles. A mixed layer that includes components of the insulating layer and components of the material mixture layer is provided at the interface between the insulating layer and the material mixture layer.
    Type: Application
    Filed: February 27, 2013
    Publication date: September 19, 2013
    Applicant: HITACHI, LTD.
    Inventors: Toshiyuki WATANABE, Kunihiko KOYAMA, Takahiro FURUTANI, Eri KOJIMA
  • Publication number: 20130224559
    Abstract: A separator for a nonaqueous electrolyte secondary battery that at least includes a resin (A) having a crosslinked structure, which is obtained by irradiating with an energy ray an oligomer polymerizable by irradiation with an energy ray. The separator has an average pore size of 0.005 to 0.5 ?m, an air permeability of 50 sec/100 mL or more and less than 500 sec/100 mL, where the air permeability is expressed as a Gurley value, and a thermal shrinkage of less than 2% at 175° C. The separator for a nonaqueous secondary battery can be produced by the production method of the present invention, which includes the steps of: applying to a substrate a separator forming composition containing the oligomer, two or more kinds of solvents having different polarity from each other, and the like; irradiating the applied composition with an energy ray; and drying the energy ray-irradiated composition.
    Type: Application
    Filed: February 23, 2012
    Publication date: August 29, 2013
    Applicant: HITACHI, LTD.
    Inventors: Takahiro Furutani, Eri Kojima, Toshiyuki Watanabe, Kunihiko Koyama
  • Publication number: 20130224575
    Abstract: A lithium ion secondary battery containing a negative electrode active material containing Si and O as constituent elements and exhibiting excellent charge-discharge cycle characteristics. The lithium ion secondary battery has a positive electrode having a positive electrode material mixture layer, a negative electrode, a separator and a nonaqueous electrolyte containing at least an electrolyte salt and an organic solvent, where the negative electrode has a negative electrode material mixture layer containing a negative electrode active material containing Si and O as constituent elements (the atomic ratio x of O to Si is 0.5?x?1.5). The nonaqueous electrolyte contains the electrolyte salt at a concentration exceeding a concentration at which conductivity in the nonaqueous electrolyte containing the electrolyte salt and the organic solvent is maximized, and the conductivity at 25° C. is 6.5 to 16 mS/cm2.
    Type: Application
    Filed: February 28, 2012
    Publication date: August 29, 2013
    Applicant: HITACHI, LTD.
    Inventors: Eri Kojima, Takahiro Furutani, Mitsuhiro Kishimi
  • Publication number: 20130084494
    Abstract: The separator for non-aqueous electrolyte secondary batteries according to the present invention includes at least a resin (A) having a crosslinked structure. The resin having the crosslinked structure is obtained by applying energy rays to at least an oligomer that is capable of being polymerized by irradiation with energy rays, and the resin (A) has a glass transition temperature higher than 0° C. and lower than 80° C. The separator for non-aqueous electrolyte secondary batteries according to the present invention can be produced using a method of the present invention including the steps of applying a separator-forming composition containing an oligomer and a solvent to a base substrate, forming a resin (A) by irradiation with energy rays, and forming pores by drying a coating film after the resin (A) has been formed. Furthermore, the non-aqueous electrolyte secondary battery of the present invention includes the separator for non-aqueous electrolyte secondary batteries according to the present invention.
    Type: Application
    Filed: September 29, 2011
    Publication date: April 4, 2013
    Inventors: Takahiro Furutani, Eri Kojima, Toshiyuki Watanabe, Kunihiko Koyama
  • Publication number: 20130078526
    Abstract: A production method for producing a separator for an electrochemical device including the steps of: applying, to a base material, a separator forming composition containing a monomer or an oligomer and a solvent; irradiating the thus formed coating with an energy ray to form a resin (A) having a cross-linked structure; and drying the coating after formation of the resin (A) to form pores, wherein, as a solvent of the separator forming composition, a solvent (a) having a solubility parameter (SP value) of 8.1 or more and less than 8.9 is used, or a solvent (b) having an SP value of 7 or more and 8 or less and a solvent (c) having an SP value of 8.9 or more and 9.9 or less are used in combination. A separator for an electrochemical device produced by the production method, and an electrochemical device of the invention including the separator.
    Type: Application
    Filed: March 12, 2012
    Publication date: March 28, 2013
    Inventors: Eri Kojima, Takahiro Furutani, Toshiyuki Watanabe, Kunihiko Koyama
  • Publication number: 20110236737
    Abstract: A non-aqueous secondary battery contains a positive electrode, a negative electrode, a separator and a non-aqueous electrolytic solution. The positive electrode contains a layered structure lithium-containing compound oxide, or a spinel lithium-containing compound oxide containing manganese as an active material. The non-aqueous electrolytic solution contains at least one additive selected from a sulfonic acid anhydride, a sulfonate ester derivative, a cyclic sulfate derivative and a cyclic sulfonate ester derivative, and a vinylene carbonate or a derivative of the vinylene carbonate.
    Type: Application
    Filed: June 6, 2011
    Publication date: September 29, 2011
    Inventors: Jinbao ZHAO, Eri KOJIMA
  • Publication number: 20110003209
    Abstract: The separator for a battery according to the present invention is a separator for a battery including an insulator layer containing a fibrous material having a heat resistant temperature of equal to or higher than 150° C., insulating inorganic fine particles and a binder, or a separator for a battery including a porous layer formed of a thermal melting resin and an insulator layer containing insulating inorganic fine particles and a binder, wherein water content per unit volume is equal to or smaller than 1 mg/cm3 when the separator is held for 24 hours in an atmosphere with a relative humidity of 60% at 20° C. The use of the separator for a battery according to the present invention makes it possible to provide a lithium secondary battery that has favorable reliability and safety and is excellent in storage characteristics and charge-discharge cycle characteristics.
    Type: Application
    Filed: September 7, 2007
    Publication date: January 6, 2011
    Inventors: Hideaki Katayama, Eri Kojima, Shigeo Aoyama, Yoshinori Sato
  • Patent number: 7829226
    Abstract: A non-aqueous secondary battery contains a positive electrode, a negative electrode, a separator and a non-aqueous electrolytic solution. The positive electrode contains a layered structure lithium-containing compound oxide, or a spinel lithium-containing compound oxide containing manganese as an active material. The non-aqueous electrolytic solution contains at least one additive selected from a sulfonic acid anhydride, a sulfonate ester derivative, a cyclic sulfate derivative and a cyclic sulfonate ester derivative, and a vinylene carbonate or a derivative of the vinylene carbonate.
    Type: Grant
    Filed: June 7, 2006
    Date of Patent: November 9, 2010
    Assignee: Hitachi Maxell, Ltd.
    Inventors: Jinbao Zhao, Eri Kojima
  • Publication number: 20100221615
    Abstract: A non-aqueous secondary battery contains a positive electrode, a negative electrode, a separator and a non-aqueous electrolytic solution. The positive electrode contains a layered structure lithium-containing compound oxide, or a spinel lithium-containing compound oxide containing manganese as an active material. The non-aqueous electrolytic solution contains at least one additive selected from a sulfonic acid anhydride, a sulfonate ester derivative, a cyclic sulfate derivative and a cyclic sulfonate ester derivative, and a vinylene carbonate or a derivative of the vinylene carbonate.
    Type: Application
    Filed: May 10, 2010
    Publication date: September 2, 2010
    Inventors: Jinbao ZHAO, Eri Kojima
  • Patent number: 7507502
    Abstract: A negative electrode of the present invention has an active material layer composed of an intermetallic compound on a collector. The intermetallic compound is capable of occluding/desorbing lithium and contains at least one kind of element A selected from Sn, In, Ge, Ga, Pb, Al, Sb, and Si, and an element X that does not substantially react with Li. In the negative electrode, a ratio Ib/Ia of highest peak intensities Ia and Ib of X-ray diffraction peaks derived from the intermetallic compound and the element A is 0.1 or less. By configuring a non-aqueous secondary battery using the above-mentioned negative electrode, the charging/discharging efficiency and cycle characteristics of a thin film electrode used for the negative electrode of the non-aqueous secondary battery are enhanced.
    Type: Grant
    Filed: March 26, 2004
    Date of Patent: March 24, 2009
    Assignee: Hitachi Maxell, Ltd.
    Inventors: Eri Kojima, Hiromu Sugiyama, Atsushi Ueda, Shigeo Aoyama
  • Publication number: 20060286459
    Abstract: A non-aqueous secondary battery contains a positive electrode, a negative electrode, a separator and a non-aqueous electrolytic solution. The positive electrode contains a layered structure lithium-containing compound oxide, or a spinel lithium-containing compound oxide containing manganese as an active material. The non-aqueous electrolytic solution contains at least one additive selected from a sulfonic acid anhydride, a sulfonate ester derivative, a cyclic sulfate derivative and a cyclic sulfonate ester derivative, and a vinylene carbonate or a derivative of the vinylene carbonate.
    Type: Application
    Filed: June 7, 2006
    Publication date: December 21, 2006
    Applicant: HITACHI MAXELL, LTD.
    Inventors: Jinbao Zhao, Eri Kojima
  • Publication number: 20040219432
    Abstract: A negative electrode of the present invention has an active material layer composed of an intermetallic compound on a collector. The intermetallic compound is capable of occluding/desorbing lithium and contains at least one kind of element A selected from Sn, In, Ge, Ga, Pb, Al, Sb, and Si, and an element X that does not substantially react with Li. In the negative electrode, a ratio Ib/Ia of highest peak intensities Ia and Ib of X-ray diffraction peaks derived from the intermetallic compound and the element A is 0.1 or less. By configuring a non-aqueous secondary battery using the above-mentioned negative electrode, the charging/discharging efficiency and cycle characteristics of a thin film electrode used for the negative electrode of the non-aqueous secondary battery are enhanced.
    Type: Application
    Filed: March 26, 2004
    Publication date: November 4, 2004
    Inventors: Eri Kojima, Hiromu Sugiyama, Atsushi Ueda, Shigeo Aoyama
  • Patent number: 5324728
    Abstract: A naphthoic acid derivative represented by the following general formula or a salt thereof: ##STR1## wherein R.sub.1, R.sub.2 and R.sub.3 are each independently a hydrogen atom, a halogen atom, a hydroxyl group, a lower alkyl group, a lower alkoxy group, a lower alkanoyloxy group, a hydroxy-lower alkyl group, a lower alkoxy-lower alkyl group, a lower alkanoyloxy-lower alkyl group or an aralkyloxy group;R.sub.4 is a hydrogen atom or a lower alkyl group;R.sub.5 is a substituted or unsubstituted aryl group or a substituted or unsubstituted heteroaromatic group;X is a group ##STR2## a cycloalkylene group, a bivalent nitrogen-containing heterocyclic group, or a group ##STR3## --R.sub.8 --NH-- or --NH--R.sub.8, where R.sub.6 and R.sub.7 are each a hydrogen atom or a lower alkyl group and R.sub.8 is a cycloalkylene group, or R.sub.6 and R.sub.7, together with R.sub.4, may form an alkylene group of 1-3 carbon atoms;Y is --S(O).sub.p --, --(CH.sub.2).sub.
    Type: Grant
    Filed: December 2, 1991
    Date of Patent: June 28, 1994
    Assignee: Fujirebio Inc.
    Inventors: Yasuo Sekine, Tetsuaki Yamaura, Masato Nishimura, Eri Kojima, Yasuko Emoto, Yasushi Higashide