Patents by Inventor Kenichi Sejima

Kenichi Sejima 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: 10901039
    Abstract: An open circuit voltage estimation device for estimating an open circuit voltage of an electric storage device includes a voltage measurement portion and a controller. The voltage measurement portion measures terminal voltages of the electric storage device. The controller is configured to: control the voltage measurement portion to measure the terminal voltages; store the terminal voltages in association with elapsed time since charge or discharge completion time; calculate a variation in terminal voltage per unit time at predetermined elapsed time since the charge or the discharge of the electric storage device is complete based on the terminal voltages measured by the voltage measurement portion; and estimate the open circuit voltage based on the predetermined elapsed time, the voltage at the predetermined elapsed time, and the variation.
    Type: Grant
    Filed: May 17, 2013
    Date of Patent: January 26, 2021
    Assignee: GS YUASA INTERNATIONAL LTD.
    Inventor: Kenichi Sejima
  • Patent number: 10830823
    Abstract: Provided is an estimation device for estimating an actual capacity of an energy storage device or a total reduction amount of the actual capacity. The estimation device includes a processor which is configured to calculate the actual capacity of the energy storage device or the total reduction amount of the actual capacity based on approximation data where a capacity change curve indicative of a transition of the actual capacity or a transition of the total reduction amount of the actual capacity with respect to an elapsed time is approximated by a plurality of straight lines.
    Type: Grant
    Filed: March 24, 2017
    Date of Patent: November 10, 2020
    Assignee: GS YUASA INTERNATIONAL LTD.
    Inventors: Tomoshige Inoue, Kenichi Sejima
  • Patent number: 10712393
    Abstract: The present invention is to improve the estimation accuracy of an SOC of a storage element. A storage element management device disclosed in the present description is a battery management device 50 that determines an SOC range indicating a state-of-charge of a secondary battery 30, and has a constitution including a central processing unit 61 that sets an overlapping range between an SOC range (i) R1, determined by a current integration method, and an SOC range (v) R2, determined by a voltage reference method in a stage where the SOC range (i) R1 is determined by the current integration method, as a new SOC range R3.
    Type: Grant
    Filed: January 13, 2017
    Date of Patent: July 14, 2020
    Assignee: GS Yuasa International Ltd.
    Inventor: Kenichi Sejima
  • Patent number: 10557893
    Abstract: A management device manages a secondary battery which includes a positive electrode having an active material with a characteristic where a potential flat portion exists in a relationship between a capacity and a potential. The management device includes a management unit which detects an occurrence of temporary degradation of the secondary battery when an SOC correlation associated value which is associated with an SOC of the secondary battery is acquired and the SOC which corresponds to the acquired SOC correlation associated value is equal to or less than a preset prescribed SOC or when a state value relating to a voltage of the secondary battery is acquired and a magnitude relationship between the acquired state value relating to the voltage of the secondary battery and a preset threshold value satisfies a predetermined condition.
    Type: Grant
    Filed: November 13, 2015
    Date of Patent: February 11, 2020
    Assignee: GS YUASA INTERNATIONAL LTD.
    Inventors: Atsushi Fukushima, Kenichi Sejima, Masashi Nakamura, Takeyuki Shiraishi
  • Patent number: 10330735
    Abstract: A state estimation device includes: a current integration unit configured to integrate a current that flows through the energy storage device; and a first estimation unit configured to estimate a full-charge capacity of the energy storage device. The energy storage device has a correlation characteristic of correlation between a residual capacity C and an open voltage V, the correlation characteristic including a constant region in which a time change in the correlation characteristic is relatively smaller than an other region.
    Type: Grant
    Filed: June 10, 2016
    Date of Patent: June 25, 2019
    Assignee: GS YUASA INTERNATIONAL LTD.
    Inventors: Kenichi Sejima, Takeyuki Shiraishi
  • Publication number: 20190025377
    Abstract: The present invention is to improve the estimation accuracy of an SOC of a storage element. A storage element management device disclosed in the present description is a battery management device 50 that determines an SOC range indicating a state-of-charge of a secondary battery 30, and has a constitution including a central processing unit 61 that sets an overlapping range between an SOC range (i) R1, determined by a current integration method, and an SOC range (v) R2, determined by a voltage reference method in a stage where the SOC range (i) R1 is determined by the current integration method, as a new SOC range R3.
    Type: Application
    Filed: January 13, 2017
    Publication date: January 24, 2019
    Inventor: Kenichi SEJIMA
  • Patent number: 10101401
    Abstract: An energy storage device management method for deciding an SOC estimated value includes: preparing first and second SOC estimation methods for estimating an SOC; and employing a predetermined value as the SOC estimated value when a first SOC region and a second SOC region are different. V-SOC correlation between a voltage and the state of charge of the energy storage device is sectioned into a plurality of SOC regions. The first SOC region is the SOC region that the SOC estimated by the first SOC estimation method belongs to, and the second SOC region is the SOC region that the SOC estimated by the second SOC estimation method belongs to. The predetermined value is set to a value close to a boundary value on a side close to the first SOC region of boundary values sectioning the second SOC region, or a value between the boundary value and an intermediate value of the second SOC region.
    Type: Grant
    Filed: February 29, 2016
    Date of Patent: October 16, 2018
    Assignee: GS YUASA INTERNATIONAL LTD.
    Inventors: Kenichi Sejima, Takeyuki Shiraishi, Yoshihiko Mizuta
  • Patent number: 9983270
    Abstract: The state of charge (SOC) estimation device includes a memory and a controller component. The memory stores data on a first correlation between an elapsed time and an estimation error in SOC estimation. The controller component executes a first estimation process and a second estimation process. The first estimation process is for estimating a first SOC and a first estimation error of the electric storage device in a non-charge/discharge state based on a terminal voltage and the elapsed time. The second estimation process is for estimating a second SOC and a second estimation error of the electric storage device in a charge/discharge state based on an accumulated charge/discharge current. The controller component calculates a total error from the first estimation error and the second estimation error. The controller component estimates the first estimation error when the elapsed time becomes equal to or longer than a reference time.
    Type: Grant
    Filed: April 1, 2014
    Date of Patent: May 29, 2018
    Assignee: GS YUASA INTERNATIONAL LTD.
    Inventor: Kenichi Sejima
  • Patent number: 9970992
    Abstract: A state estimation device includes: a voltage detecting unit that detects voltages of energy storage devices; and an estimating unit that estimates a charge amount difference between at least two of the energy storage devices. At a reference time point T0 during constant current charging, the estimating unit performs: specific voltage setting for setting, as a specific voltage V0, a voltage of a low-voltage energy storage device at the reference time point T0; time obtaining for obtaining a time point at which a voltage of a high-voltage energy storage device reaches the specific voltage V0; and charge amount difference estimating for estimating the charge amount difference between the at least two energy storage devices based on the reference time point T0, the time point obtained in the time obtaining process, and a current flowing through the plurality of energy storage devices during the constant current charging.
    Type: Grant
    Filed: January 25, 2017
    Date of Patent: May 15, 2018
    Assignee: GS YUASA INTERNATIONAL LTD.
    Inventor: Kenichi Sejima
  • Publication number: 20170371000
    Abstract: A management device manages a secondary battery which includes a positive electrode having an active material with a characteristic where a potential flat portion exists in a relationship between a capacity and a potential. The management device includes a management unit which detects an occurrence of temporary degradation of the secondary battery when an SOC correlation associated value which is associated with an SOC of the secondary battery is acquired and the SOC which corresponds to the acquired SOC correlation associated value is equal to or less than a preset prescribed SOC or when a state value relating to a voltage of the secondary battery is acquired and a magnitude relationship between the acquired state value relating to the voltage of the secondary battery and a preset threshold value satisfies a predetermined condition.
    Type: Application
    Filed: November 13, 2015
    Publication date: December 28, 2017
    Inventors: Atsushi FUKUSHIMA, Kenichi SEJIMA, Masashi NAKAMURA, Takeyuki SHIRAISHI
  • Publication number: 20170285110
    Abstract: Provided is an estimation device for estimating an actual capacity of an energy storage device or a total reduction amount of the actual capacity. The estimation device includes a processor which is configured to calculate the actual capacity of the energy storage device or the total reduction amount of the actual capacity based on approximation data where a capacity change curve indicative of a transition of the actual capacity or a transition of the total reduction amount of the actual capacity with respect to an elapsed time is approximated by a plurality of straight lines.
    Type: Application
    Filed: March 24, 2017
    Publication date: October 5, 2017
    Inventors: Tomoshige INOUE, Kenichi SEJIMA
  • Publication number: 20170212171
    Abstract: A state estimation device includes: a voltage detecting unit that detects voltages of energy storage devices; and an estimating unit that estimates a charge amount difference between at least two of the energy storage devices. At a reference time point T0 during constant current charging, the estimating unit performs: specific voltage setting for setting, as a specific voltage V0, a voltage of a low-voltage energy storage device at the reference time point T0; time obtaining for obtaining a time point at which a voltage of a high-voltage energy storage device reaches the specific voltage V0; and charge amount difference estimating for estimating the charge amount difference between the at least two energy storage devices based on the reference time point T0, the time point obtained in the time obtaining process, and a current flowing through the plurality of energy storage devices during the constant current charging.
    Type: Application
    Filed: January 25, 2017
    Publication date: July 27, 2017
    Inventor: Kenichi SEJIMA
  • Publication number: 20160370431
    Abstract: A state estimation device includes: a current integration unit configured to integrate a current that flows through the energy storage device; and a first estimation unit configured to estimate a full-charge capacity of the energy storage device. The energy storage device has a correlation characteristic of correlation between a residual capacity C and an open voltage V, the correlation characteristic including a constant region in which a time change in the correlation characteristic is relatively smaller than an other region.
    Type: Application
    Filed: June 10, 2016
    Publication date: December 22, 2016
    Inventors: Kenichi SEJIMA, Takeyuki Shiraishi
  • Patent number: 9506988
    Abstract: A condition estimation device for estimating condition of an electric storage device includes a voltage detector and a controller. The voltage detector is configured to detect a voltage of the electric storage device. The controller is configured to perform a distinctive point detection process to detect a distinctive point based on the voltage detected by the voltage detector, and an estimation process to estimate the condition of the electric storage device based on the distinctive point detected in the distinctive point detection process. The distinctive point is a point at which a variation in voltage per unit remaining capacity or per unit time of the electric storage device during charge or discharge is a local maximum value.
    Type: Grant
    Filed: October 31, 2013
    Date of Patent: November 29, 2016
    Assignee: GS YUASA INTERNATIONAL LTD.
    Inventors: Kenichi Sejima, Masashi Nakamura
  • Publication number: 20160259012
    Abstract: An energy storage device management method for deciding an SOC estimated value includes: preparing first and second SOC estimation methods for estimating an SOC; and employing a predetermined value as the SOC estimated value when a first SOC region and a second SOC region are different. V-SOC correlation between a voltage and the state of charge of the energy storage device is sectioned into a plurality of SOC regions. The first SOC region is the SOC region that the SOC estimated by the first SOC estimation method belongs to, and the second SOC region is the SOC region that the SOC estimated by the second SOC estimation method belongs to. The predetermined value is set to a value close to a boundary value on a side close to the first SOC region of boundary values sectioning the second SOC region, or a value between the boundary value and an intermediate value of the second SOC region.
    Type: Application
    Filed: February 29, 2016
    Publication date: September 8, 2016
    Inventors: Kenichi SEJIMA, Takeyuki SHIRAISHI, Yoshihiko MIZUTA
  • Patent number: 9041405
    Abstract: A condition estimation device includes a voltage measurement circuit, memory, and a controller. The voltage measurement circuit measures an open circuit voltage (OCV) of an electric storage device. The memory is configured to store first information on a correlation between a positive electrode potential and an electric storage capacity and second information on a correlation between a negative electrode potential and an electric storage capacity. The controller is configured to: measure an OCV under charge or discharge; calculate an electric storage capacity of the electric storage device having the OCV equal to a reference voltage; correct at least one of the first information and the second information such that a potential difference at the calculated capacity is equal to the reference voltage; and generate an OCV characteristic based on the first and the second information after the at least one of the first and the second information is corrected.
    Type: Grant
    Filed: September 11, 2013
    Date of Patent: May 26, 2015
    Assignee: GS Yuasa International Ltd.
    Inventors: Kenichi Sejima, Yoshihiko Mizuta, Masashi Nakamura, Hiroshi Sekiguchi, Hidefumi Hasegawa, Shinya Kitano
  • Publication number: 20140303914
    Abstract: The state of charge (SOC) estimation device includes a memory and a controller component. The memory stores data on a first correlation between an elapsed time and an estimation error in SOC estimation. The controller component executes a first estimation process and a second estimation process. The first estimation process is for estimating a first SOC and a first estimation error of the electric storage device in a non-charge/discharge state based on a terminal voltage and the elapsed time. The second estimation process is for estimating a second SOC and a second estimation error of the electric storage device in a charge/discharge state based on an accumulated charge/discharge current. The controller component calculates a total error from the first estimation error and the second estimation error. The controller component estimates the first estimation error when the elapsed time becomes equal to or longer than a reference time.
    Type: Application
    Filed: April 1, 2014
    Publication date: October 9, 2014
    Applicant: GS Yuasa International Ltd.
    Inventor: Kenichi SEJIMA
  • Publication number: 20140125345
    Abstract: A condition estimation device for estimating condition of an electric storage device includes a voltage detector and a controller. The voltage detector is configured to detect a voltage of the electric storage device. The controller is configured to perform a distinctive point detection process to detect a distinctive point based on the voltage detected by the voltage detector, and an estimation process to estimate the condition of the electric storage device based on the distinctive point detected in the distinctive point detection process. The distinctive point is a point at which a variation in voltage per unit remaining capacity or per unit time of the electric storage device during charge or discharge is a local maximum value.
    Type: Application
    Filed: October 31, 2013
    Publication date: May 8, 2014
    Applicant: GS Yuasa International Ltd.
    Inventors: Kenichi Sejima, Masashi Nakamura
  • Publication number: 20140111214
    Abstract: An electric storage condition detecting apparatus includes a voltage detector configured to detect a voltage of an electric storage device, and a controller configured to determine stabilizing time based on data corresponding to a charging capacity of the electric storage device, and the stabilizing time is required for stabilizing an open circuit voltage of the electric storage device.
    Type: Application
    Filed: October 21, 2013
    Publication date: April 24, 2014
    Applicant: GS Yuasa International Ltd.
    Inventor: Kenichi Sejima
  • Publication number: 20140084939
    Abstract: A condition estimation device includes a voltage measurement circuit, memory, and a controller. The voltage measurement circuit measures an open circuit voltage (OCV) of an electric storage device. The memory is configured to store first information on a correlation between a positive electrode potential and an electric storage capacity and second information on a correlation between a negative electrode potential and an electric storage capacity. The controller is configured to: measure an OCV under charge or discharge; calculate an electric storage capacity of the electric storage device having the OCV equal to a reference voltage; correct at least one of the first information and the second information such that a potential difference at the calculated capacity is equal to the reference voltage; and generate an OCV characteristic based on the first and the second information after the at least one of the first and the second information is corrected.
    Type: Application
    Filed: September 11, 2013
    Publication date: March 27, 2014
    Applicant: GS Yuasa International Ltd.
    Inventors: Kenichi SEJIMA, Yoshihiko Mizuta, Masashi Nakamura, Hiroshi Sekiguchi, Hidefumi Hasegawa, Shinya Kitano