Patents by Inventor Jiro Iriyama

Jiro Iriyama 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: 10374219
    Abstract: The object of an exemplary embodiment of the invention is to provide a lithium ion secondary battery having an excellent charge and discharge cycle property. An exemplary embodiment of the invention is a lithium ion secondary battery, comprising a battery assembly in which a positive electrode and a negative electrode are stacked through a separator and a package in which the battery assembly and an electrolyte are placed; wherein the negative electrode comprises a negative electrode collector which is composed of a metal and a negative electrode active material layer which is formed on the negative electrode collector and which comprises a negative electrode active material and a binder; wherein the negative electrode collector and the negative electrode active material layer have a crack which is formed so as to be communicated with each of them; and wherein the crack reaches an outer peripheral edge from an inside of the negative electrode.
    Type: Grant
    Filed: April 13, 2012
    Date of Patent: August 6, 2019
    Assignee: NEC Corporation
    Inventors: Ryuichi Kasahara, Jiro Iriyama, Shin Serizawa, Hiroo Takahashi, Tatsuji Numata
  • Patent number: 10333174
    Abstract: The present invention relates to a lithium ion secondary battery comprising a positive electrode having a coating amount per unit area of 50 mg/cm2 or more and an electrode density of 3.3 g/cc or more and a negative electrode having a coating amount per unit area of 24 mg/cm2 or more and an electrode density of 1.5 g/cc or more, a separator having a shrinking ratio of 2% or less by heat treatment at 80° C. for 6 hours, and an electrolyte solution comprising at least one sulfonic acid ester compound, and a ratio of a sulfur content in the central portion (As) and a sulfur content in the edge portion (Bs) of the positive electrode and the negative electrode, in each, is 0.7?As/Bs?1.1.
    Type: Grant
    Filed: March 22, 2016
    Date of Patent: June 25, 2019
    Assignee: NEC Corporation
    Inventors: Daisuke Kawasaki, Kenichi Shimura, Noboru Yoshida, Kazuhiko Inoue, Jiro Iriyama
  • Publication number: 20180212235
    Abstract: Provided are a lithium secondary battery wherein gas generation associated with charging and discharging can be suppressed even in case where silicon and silicon oxide are contained as negative electrode active materials, and wherein deformation due to the gas generation can be suppressed even in case where a resin film is used as an outer package; and a method for manufacturing the lithium secondary battery. A lithium secondary battery comprises a negative electrode containing a negative electrode active material, a positive electrode containing a positive electrode active material, and an electrolytic solution used to immerse the negative electrode active material and the positive electrode active material, wherein the negative electrode active material contains silicon and silicon oxide that have been subjected to a reduction treatment.
    Type: Application
    Filed: March 19, 2018
    Publication date: July 26, 2018
    Applicant: NEC Corporation
    Inventors: Tetsuya KAJITA, Jiro IRIYAMA, Shin SERIZAWA
  • Publication number: 20180175449
    Abstract: There is provided a lithium ion secondary battery having a positive electrode comprising a lithium nickel composite oxide as a positive electrode active material and a separator consisting of one or more layers selected from polyimide layer, polyamide layer, the battery having a low self-discharge failure rate even after long term storage. The present invention relates to a lithium ion secondary battery having a positive electrode comprising a lithium nickel composite oxide and a separator consisting of one or more layers selected from polyimide layer, polyamide layer, and polyamide imide layer, wherein the battery comprises an acid and/or an acid anhydride in an electrolyte solution and/or a member in contact with the electrolyte solution.
    Type: Application
    Filed: May 9, 2016
    Publication date: June 21, 2018
    Applicant: NEC CORPORATION
    Inventors: Jiro IRIYAMA, Kenichi SHIMURA, Kazuhiko INOUE
  • Publication number: 20180159105
    Abstract: There is provided a lithium ion secondary battery having a positive electrode comprising a lithium nickel composite oxide as a positive electrode active material, and a separator consisting of one or more layers selected from a polyimide layer, a polyamide layer, and a polyamide imide layer, the lithium secondary battery exhibiting a low self-discharge failure rate even after long term storage. The present invention pertains to a lithium ion secondary battery having a positive electrode comprising a positive electrode active material comprising a lithium nickel composite oxide and a separator consisting of one or more layers selected from a polyimide layer, a polyamide layer, and a polyamide imide layer, wherein a suspension prepared by mixing the positive electrode active material and a deionized water at a mass ratio of 2:98 shows a pH of 9.3 or less.
    Type: Application
    Filed: May 9, 2016
    Publication date: June 7, 2018
    Applicant: NEC CORPORATION
    Inventors: Jiro IRIYAMA, Kazuhiko INOUE, Kenichi SHIMURA
  • Patent number: 9985286
    Abstract: A negative electrode active material comprising silicon oxide satisfying the following Equation 1 and Equation 2 when solid state NMR (29Si-DDMAS) of silicon is measured for the silicon oxide after performing charging at least once is excellent in the performance as a negative electrode active material for a lithium secondary battery; 0.42?S1/(S1+S2+S3)?0.55??(Equation 1) 0.21?S3/(S1+S2+S3)?0.26,??(Equation 2) in which S1 is a sum of peak areas of a group of signals assigned to Si having a Si—Si bond and having peaks at 0 to ?15 ppm, ?55 ppm, ?84 ppm and ?88 ppm, S2 is a sum of peak areas of a group of signals assigned to Si having a Si(OH)4-n(OSi)n (n=3, 4) structure and having peaks at ?100 ppm and ?120 ppm, and S3 is a sum of peak areas of a group of signals assigned to Si having a Si(OLi)4-n(OSi)n (n=0, 1, 2, 3) structure and having peaks at ?66 ppm, ?74 ppm, ?85 ppm and ?96 ppm.
    Type: Grant
    Filed: October 28, 2013
    Date of Patent: May 29, 2018
    Assignee: NEC Corporation
    Inventors: Jiro Iriyama, Daisuke Kawasaki, Emiko Fujii, Shin Serizawa, Hiroo Takahashi
  • Publication number: 20180090792
    Abstract: The present invention relates to a lithium ion secondary battery comprising a positive electrode having a coating amount per unit area of 50 mg/cm2 or more and an electrode density of 3.3 g/cc or more and a negative electrode having a coating amount per unit area of 24 mg/cm2 or more and an electrode density of 1.5 g/cc or more, a separator having a shrinking ratio of 2% or less by heat treatment at 80° C. for 6 hours, and an electrolyte solution comprising at least one sulfonic acid ester compound, and a ratio of a sulfur content in the central portion (As) and a sulfur content in the edge portion (Bs) of the positive electrode and the negative electrode, in each, is 0.7?As/Bs?1.1.
    Type: Application
    Filed: March 22, 2016
    Publication date: March 29, 2018
    Applicant: NEC CORPORATION
    Inventors: Daisuke KAWASAKI, Kenichi SHIMURA, Noboru YOSHIDA, Kazuhiko INOUE, Jiro IRIYAMA
  • Publication number: 20180076479
    Abstract: The present invention relates to a lithium ion secondary battery comprising an electrode element comprising a positive electrode, a negative electrode and a separator, and an electrolyte solution, wherein the separator has a shrinking ratio of 2% or less by heat treatment at 90 ° C. for 6 hours, and a contest of physically adsorbed water of the electrode element is 2% by mass or less, or a content of chemically adsorbed water in a positive electrode active material layer of the positive electrode is 1% by mass or less.
    Type: Application
    Filed: March 22, 2016
    Publication date: March 15, 2018
    Applicant: NEC CORPORATION
    Inventors: Daisuke KAWASAKI, Kenichi SHlMURA, Noboru YOSHIDA, Kazuhiko INOUE, Jiro IRIYAMA
  • Publication number: 20180076449
    Abstract: A negative electrode for a lithium ion secondary battery is disclosed, which comprises, as active materials, (a) at least one material selected from metals capable of forming an alloy with lithium and metal oxides capable of absorbing and desorbing lithium ions (hereinafter referred to as metal and/or metal oxide), and (b) a surface-coated carbon material capable of absorbing and desorbing lithium ions; wherein, an average value of circularity of the metal and/or metal oxide particles defined by following formula (1) is 0.78 or more; Circularity=4?S/L2 ??(1) wherein S is an area of a projected image of particle and L is a circumferential length of the projected image of particle. The lithium ion secondary battery having this electrode has improved cycle characteristics.
    Type: Application
    Filed: March 17, 2016
    Publication date: March 15, 2018
    Inventors: Jiro IRIYAMA, Ikiko SHIMANUKI, Takeshi AZAMI
  • Patent number: 9893350
    Abstract: The present invention relates to a lithium secondary battery, wherein a peak at 167 to 171 eV and a peak at 162 to 166 eV are present in XPS analysis of sulfur (S2p) of a positive electrode surface, and P169/P164 is in the range of 0.7 to 2.0 wherein the P 169/P 164 is the ratio between the intensity of the peak at 167 to 171 eV (P169) and the intensity of the peak at 162 to 166 eV (P164). The present invention can provide a lithium secondary battery having excellent cycle characteristics.
    Type: Grant
    Filed: March 4, 2014
    Date of Patent: February 13, 2018
    Assignee: NEC Corporation
    Inventor: Jiro Iriyama
  • Patent number: 9859589
    Abstract: It is an object of the present invention to provide a method for producing a secondary battery in which water in the outer package can be removed even when the secondary battery includes an electrolytic solution containing a halogen-containing compound.
    Type: Grant
    Filed: August 8, 2014
    Date of Patent: January 2, 2018
    Assignee: NEC Corporation
    Inventors: Jiro Iriyama, Makihiro Otohata, Kazuaki Matsumoto, Ikiko Shimanuki
  • Patent number: 9831526
    Abstract: The present invention provides a lithium secondary battery, wherein a peak at 167 to 171 eV and a peak at 160 to 164 eV are present in XPS analysis of sulfur on a negative electrode surface (S2p), and P169/P162 is in the range of 0.7 to 2.0 wherein the P169/P162 is the ratio between the intensity of the peak at 167 to 171 eV (P169) and the intensity of the peak at 160 to 164 eV (P162).
    Type: Grant
    Filed: October 29, 2013
    Date of Patent: November 28, 2017
    Assignee: NEC Corporation
    Inventor: Jiro Iriyama
  • Patent number: 9768476
    Abstract: A control system for a lithium secondary battery measures a voltage V of a negative electrode that uses silicon oxide as a negative electrode active material, with respect to a lithium reference electrode and a discharge capacity Q of the lithium secondary battery during discharge of the lithium secondary battery; generates a V?dQ/dV curve representing a relationship between dQ/dV, which is a proportion of an amount of change dQ in the discharge capacity Q to an amount of change dV in the voltage V, and the voltage V; calculates an intensity ratio of two peaks appearing on the V?dQ/dV curve for two voltage values in the voltage V; and senses a state of the negative electrode utilizing the intensity ratio.
    Type: Grant
    Filed: March 27, 2015
    Date of Patent: September 19, 2017
    Assignees: NEC CORPORATION, NEC ENERGY DEVICES, LTD.
    Inventors: Jiro Iriyama, Tetsuya Kajita, Daisuke Kawasaki, Ryuichi Kasahara, Tatsuji Numata
  • Patent number: 9627687
    Abstract: An exemplary embodiment provides a lithium ion secondary battery using a high energy type anode, which enables long-life operation thereof. A secondary battery according to an exemplary embodiment comprises an electrode element in which a cathode and an anode are oppositely disposed, an electrolytic solution, and an outer packaging body which encloses the electrode element and the electrolytic solution inside; wherein the anode is formed by binding an anode active material, which comprises carbon material (a) that can absorb and desorb a lithium ion, metal (b) that can be alloyed with lithium, and metal oxide (c) that can absorb and desorb a lithium ion, to an anode collector with an anode binder; and wherein the electrolytic solution comprises a liquid medium which is hard to generate carbon dioxide at a concentration of 10 to 80 vol %.
    Type: Grant
    Filed: September 29, 2010
    Date of Patent: April 18, 2017
    Assignees: NEC ENERGY DEVICES, LTD., NEC CORPORATION
    Inventors: Daisuke Kawasaki, Shinako Kaneko, Jiro Iriyama
  • Publication number: 20160308252
    Abstract: It is an object of the present invention to provide a method for producing a secondary battery in which water in the outer package can be removed even when the secondary battery includes an electrolytic solution containing a halogen-containing compound.
    Type: Application
    Filed: August 8, 2014
    Publication date: October 20, 2016
    Inventors: Jiro IRIYAMA, Makihiro OTOHATA, Kazuaki MATSUMOTO, Ikiko SHIMANUKI
  • Publication number: 20160285091
    Abstract: A negative electrode active material comprising silicon oxide satisfying the following Equation 1 and Equation 2 when solid state NMR (29Si-DDMAS) of silicon is measured for the silicon oxide after performing charging at least once is excellent in the performance as a negative electrode active material for a lithium secondary battery; 0.42?S1/(S1+S2+S3)?0.55??(Equation 1) 0.21?S3/(S1+S2+S3)?0.26,??(Equation 2) in which S1 is a sum of peak areas of a group of signals assigned to Si having a Si—Si bond and having peaks at 0 to ?15 ppm, ?55 ppm, ?84 ppm and ?88 ppm, S2 is a sum of peak areas of a group of signals assigned to Si having a Si(OH)4-n(OSi)n (n=3, 4) structure and having peaks at ?100 ppm and ?120 ppm, and S3 is a sum of peak areas of a group of signals assigned to Si having a Si(OLi)4-n(OSi)n (n=0, 1, 2, 3) structure and having peaks at ?66 ppm, ?74 ppm, ?85 ppm and ?96 ppm.
    Type: Application
    Filed: October 28, 2013
    Publication date: September 29, 2016
    Inventors: Jiro IRIYAMA, Daisuke KAWASAKI, Emiko FUJII, Shin SERIZAWA, Hiroo TAKAHASHI
  • Patent number: 9443661
    Abstract: An object of the present invention is to provide a power storage device with excellent cycle property, employing a cathode containing a nitroxyl polymer. To attain the object in the present invention, in the power storage device employing a cathode comprising a nitroxyl polymer, a lithium or lithium alloy anode is used as an anode active material and the cathode is in direct contact with the anode.
    Type: Grant
    Filed: December 17, 2004
    Date of Patent: September 13, 2016
    Assignee: NEC CORPORATION
    Inventors: Kentaro Nakahara, Jiro Iriyama, Shigeyuki Iwasa, Masahiro Suguro, Masaharu Satoh
  • Patent number: 9325010
    Abstract: Provided is a negative electrode active material for a lithium secondary cell, the material having the function of a binder for the active material, and being capable of stable reversible reactions with lithium. Also, provided are an extended-life lithium secondary cell having improved energy density and stable charge/discharge, and a method for producing the same. The negative electrode active material for a lithium secondary cell is polyimide represented by formula (1) (wherein R1 and R2 independently denote an alkyl, alkoxy, acyl, phenyl, or phenoxy group).
    Type: Grant
    Filed: April 27, 2012
    Date of Patent: April 26, 2016
    Assignee: NEC Corporation
    Inventors: Jiro Iriyama, Tetsuya Kajita, Daisuke Kawasaki, Tatsuji Numata, Kazuhiko Inoue
  • Patent number: 9263741
    Abstract: There is provided a negative electrode for a nonaqueous electrolyte secondary battery in which when a battery is formed, the energy density is high, and moreover, the decrease in charge and discharge capacity is small even if charge and discharge are repeated. By using silicon oxide particles having a particle diameter in a particular range as a starting raw material, and heating these particles in the range of 850° C. to 1050° C., Si microcrystals are deposited on the surfaces of the particles. Then, by performing doping of Li, a structure comprising a plurality of protrusions having height and cross-sectional area in a particular range is formed on the surfaces. The average value of the height of the above protrusions is 2% to 19% of the average particle diameter of the above lithium-containing silicon oxide particles.
    Type: Grant
    Filed: December 17, 2009
    Date of Patent: February 16, 2016
    Assignee: NEC Energy Devices, Ltd.
    Inventors: Jiro Iriyama, Ryuichi Kasahara, Tetsuya Kajita, Tatsuji Numata
  • Publication number: 20160036051
    Abstract: The present invention relates to a lithium secondary battery, wherein a peak at 167 to 171 eV and a peak at 162 to 166 eV are present in XPS analysis of sulfur (S2p) of a positive electrode surface, and P169/P164 is in the range of 0.7 to 2.0 wherein the P 169/P 164 is the ratio between the intensity of the peak at 167 to 171 eV (P169) and the intensity of the peak at 162 to 166 eV (P164). The present invention can provide a lithium secondary battery having excellent cycle characteristics.
    Type: Application
    Filed: March 4, 2014
    Publication date: February 4, 2016
    Applicant: NEC Corporation
    Inventor: Jiro IRIYAMA