Patents by Inventor Keiichiro Ohkawa

Keiichiro Ohkawa 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).

  • Publication number: 20230039183
    Abstract: A battery control apparatus for a battery system includes: a first operation unit that computes a first state of charge of a battery according to a first technique on the basis of an electric current value, a voltage value, and an internal resistance value of the battery; a second operation unit that computes a second state of charge of the battery according to a second technique different from the first technique; and a correction unit that corrects the internal resistance value of the battery. if a difference equal to or more than a specified value is detected between the first state of charge and the second state of charge, the correction unit corrects the internal resistance value of the battery with a resistance correction amount according to the difference and the electric current value.
    Type: Application
    Filed: September 18, 2020
    Publication date: February 9, 2023
    Inventors: Keiichiro OHKAWA, Ryohhei NAKAO
  • Patent number: 11532841
    Abstract: A current of a storage battery is appropriately controlled depending on the situation. In a battery controller, a battery information acquiring unit acquires information on the storage battery. A first allowable current calculating unit calculates a first allowable current of a battery module in accordance with a rated value of a component through which a current flows by charging or discharging of the battery module. A second allowable current calculating unit calculates a second allowable current of the battery module in accordance with an SOC of the battery module on the basis of the information acquired by the battery information acquiring unit. A third allowable current calculating unit calculates a third allowable current of the battery module in accordance with an SOH of the battery module on the basis of the information acquired by the battery information acquiring unit.
    Type: Grant
    Filed: December 28, 2020
    Date of Patent: December 20, 2022
    Assignee: Vehicle Energy Japan Inc.
    Inventors: Shin Yamauchi, Kei Sakabe, Masahiro Yonemoto, Takanori Yamazoe, Keiichiro Ohkawa, Ryohhei Nakao
  • Patent number: 11515579
    Abstract: To sufficiently exert charging and discharging performance of a cell while reliably protecting the cell, a battery controller determines ?Vlimit which is a limit value for a difference between a CCV and an OCV of a cell module, which is a secondary cell, and determines at least one of an upper limit voltage and a lower limit voltage of the cell module. An allowable current of the cell module is calculated based on the ?Vlimit and at least one of the upper limit voltage and the lower limit voltage determined in this manner.
    Type: Grant
    Filed: December 2, 2016
    Date of Patent: November 29, 2022
    Assignee: VEHICLE ENERGY JAPAN, INC.
    Inventors: Kei Sakabe, Keiichiro Ohkawa, Ryohhei Nakao, Masahiro Yonemoto
  • Patent number: 11374425
    Abstract: Provided is a battery system in which a battery cell does not exceed a use limit temperature, and a time taken for returning to the charging/discharging process is shortened even if a frequency for the battery system to stop a charging/discharging process is reduced and the charging/discharging process is stopped. The battery system disclosed in the invention includes a plurality of battery cells and a control circuit which controls a charging/discharging current of the battery cell. The control circuit performs a plurality of temperature rising estimations on the basis of a battery temperature, a charging/discharging current, and a time width of a time window. The control circuit selects the charging/discharging current corresponding to a temperature rising estimation in which the temperature of the battery cell does not exceed a use limit temperature among the temperature rising estimations.
    Type: Grant
    Filed: February 6, 2018
    Date of Patent: June 28, 2022
    Assignee: Vehicle Energy Japan Inc.
    Inventors: Fanny Matthey, Shin Yamauchi, Kei Sakabe, Ryohhei Nakao, Daiki Komatsu, Keiichiro Ohkawa
  • Publication number: 20220163591
    Abstract: A battery management apparatus 102 is an apparatus which manages a chargeable and dischargeable battery, and includes: a battery state calculation unit 501 which calculates a state of charge SOC representing the state of charge of the battery, and a charge capacity fade SOHQ representing a deterioration degree; a mid voltage calculation unit 502 which calculates a mid voltage that is present between the discharge voltage in a current state of charge of the battery, and a voltage value representing the discharge voltage in a minimum state of charge of the battery; a remaining capacity calculation unit 503 which calculates a remaining capacity of the battery, based on the state of charge SOC and the charge capacity fade SOHQ; and an available energy calculation unit 504 which calculates available energy of the battery, based on the mid voltage and the remaining capacity.
    Type: Application
    Filed: March 17, 2020
    Publication date: May 26, 2022
    Applicant: Vehicle Energy Japan Inc.
    Inventors: Fanny MATTHEY, Ryohhei NAKAO, Keiichiro OHKAWA, Yosuke WADA
  • Publication number: 20220131400
    Abstract: An appropriate upper limit voltage is set to enable maximum charging performance of a secondary battery to be exhibited while effectively suppressing degradation of the secondary battery. An assembled battery control unit determines an upper limit voltage during charge of the secondary battery and calculates chargeable power of the secondary battery based on the upper limit voltage. The assembled battery control unit has an upper limit voltage calculating unit which calculates a voltage history of the secondary battery based on time series data of a voltage of the secondary battery and which calculates the upper limit voltage based on the voltage history.
    Type: Application
    Filed: December 4, 2019
    Publication date: April 28, 2022
    Applicant: VEHICLE ENERGY JAPAN INC.
    Inventors: Ryohhei NAKAO, Keiichiro OHKAWA, Yasuo ARISHIMA, Hironori SASAKI
  • Patent number: 11247581
    Abstract: A battery control device capable of obtaining an allowable charge/discharge current value can further accurately reflect a polarization state of a battery. A battery controller includes a first allowable current value calculation unit, a battery equivalent circuit model, and a correction amount calculation unit. Assuming a non-polarization state, a current limit value of the battery based on an open circuit voltage and upper and lower limit voltages set in the battery, the first allowable current value calculation unit calculates a first allowable current value Imax1. The battery equivalent circuit model estimates a polarization state of the battery when the current limit value is being calculated. The correction unit calculates an allowable current value correction value based on the estimated polarization state for correcting Imax1. A second allowable current value Imax2 which is the corrected first allowable current value is output as an allowable charge/discharge current value of the battery.
    Type: Grant
    Filed: May 18, 2020
    Date of Patent: February 15, 2022
    Assignee: VEHICLE ENERGY JAPAN, INC.
    Inventors: Kei Sakabe, Keiichiro Ohkawa, Takanori Yamazoe, Ryohhei Nakao, Masahiro Yonemoto
  • Patent number: 11226376
    Abstract: To perform charge/discharge control of a storage battery at an appropriate timing. In a battery controller, a battery information acquisition unit acquires information on the storage battery. A degradation progression rate calculation unit calculates a degradation progression rate of the storage battery based on the information acquired by the battery information acquisition unit. A limit value setting unit sets a limit value for controlling charge/discharge of the storage battery based on the degradation progression rate calculated by the degradation progression rate calculation unit. A timing determination unit determines a timing at which the limit value needs to be output based on the information acquired by the battery information acquisition unit. A limit value output unit outputs the limit value to a host controller based on the timing determined by the timing determination unit.
    Type: Grant
    Filed: August 8, 2016
    Date of Patent: January 18, 2022
    Assignee: Vehicle Energy Japan Inc.
    Inventors: Shin Yamauchi, Kei Sakabe, Masahiro Yonemoto, Takanori Yamazoe, Keiichiro Ohkawa, Ryohhei Nakao
  • Publication number: 20210341541
    Abstract: A battery control unit has an SOCv operation unit which calculates a state of charge SOCv based on voltage of a battery, a ?SOCi operation unit which calculates an amount of change ?SOCi of the state of charge based on current value of the battery, a weight operation unit which calculates a weight W, and an SOCc operation unit which calculates a final SOC (SOCc) based on the SOCv, the ?SOCi and the weight W. Terms forming an operational expression of the SOCc are retained, by using a determination threshold, as a sum SOCc_Big of terms of a large value group and a sum SOCc_Small of terms of a small value group, and used in calculating the SOCc of a subsequent operation period. By using the SOCc_Big and the SOCc_Small, it is possible to prevent the accumulation of errors caused by information loss that occurred when repeatedly operating the SOCc.
    Type: Application
    Filed: September 25, 2019
    Publication date: November 4, 2021
    Applicant: Vehicle Energy Japan Inc.
    Inventors: Miyuki AKATSU, Keiichiro OHKAWA
  • Publication number: 20210311127
    Abstract: An apparatus coupled to an assembled battery with a plurality of serially-connected cells and for setting any one of the plurality of cells as a target cell and estimating a state of charge of the target cell includes: a cell voltage acquisition unit that acquires a measurement result of a closed circuit voltage of the target cell; a reference cell information acquisition unit that sets a reference cell with respect to the plurality of cells and acquires a closed circuit voltage and an open circuit voltage of the reference cell and a reference SOC value representing a state of charge of the reference cell; a temporary SOC operation unit that finds a temporary SOC value representing a temporary state of charge of the target cell on the basis of the closed circuit voltage of the target cell and the closed circuit voltage and the open circuit voltage of the reference cell; and an SOC operation unit that finds an SOC value representing the state of charge of the target cell by using a result of smoothing processi
    Type: Application
    Filed: March 18, 2019
    Publication date: October 7, 2021
    Inventors: Yosuke WADA, Keiichiro OHKAWA
  • Patent number: 11124072
    Abstract: Provided are a battery control device which can estimates an SOC of a battery with a high accuracy, and an electric motor vehicle system. The battery control device (190) includes a feature amount calculation unit (152) which calculates a feature amount indicating a charging/discharging pattern of the battery, a first charging state amount calculation unit (151-1) which calculates a first charging state amount (SOCi) of the battery on the basis of a first battery state amount, a second charging state amount calculation unit (151-2) which calculates a second charging state amount (SOCv) of the battery on the basis of a second battery state amount, and a third charging state amount calculation unit (151-3) which calculates a third charging state amount (SOC(t)) on the basis of the feature amount, the first charging stage amount, the second charging stage amount.
    Type: Grant
    Filed: March 16, 2016
    Date of Patent: September 21, 2021
    Assignee: VEHICLE ENERGY JAPAN INC.
    Inventors: Ryohhei Nakao, Keiichiro Ohkawa
  • Patent number: 11084385
    Abstract: In an existing permissible current computation algorithm, an excessive current is caused to flow by controlling the battery having a steep change region in the battery characteristic. On the other hand, when the current is reduced and the output is suppressed, the battery performance cannot be sufficiently utilized. Moreover, with countermeasures to increase the number of data points, the amount of data increases and thus can not be installed in the microcomputer.
    Type: Grant
    Filed: July 28, 2017
    Date of Patent: August 10, 2021
    Assignee: VEHICLE ENERGY JAPAN INC.
    Inventors: Daiki Komatsu, Kei Sakabe, Masahiro Yonemoto, Shin Yamauchi, Keiichiro Ohkawa, Ryohhei Nakao
  • Publication number: 20210119272
    Abstract: A current of a storage battery is appropriately controlled depending on the situation. In a battery controller, a battery information acquiring unit acquires information on the storage battery. A first allowable current calculating unit calculates a first allowable current of a battery module in accordance with a rated value of a component through which a current flows by charging or discharging of the battery module. A second allowable current calculating unit calculates a second allowable current of the battery module in accordance with an SOC of the battery module on the basis of the information acquired by the battery information acquiring unit. A third allowable current calculating unit calculates a third allowable current of the battery module in accordance with an SOH of the battery module on the basis of the information acquired by the battery information acquiring unit.
    Type: Application
    Filed: December 28, 2020
    Publication date: April 22, 2021
    Inventors: Shin YAMAUCHI, Kei SAKABE, Masahiro YONEMOTO, Takanori YAMAZOE, Keiichiro OHKAWA, Ryohhei NAKAO
  • Patent number: 10955479
    Abstract: Provided is a battery control device that can achieve an improvement in computation accuracy of an internal resistance and an SOH. The battery control device includes an SOH computation unit which calculates an internal resistance value of a battery, and controls the battery on the basis of the internal resistance value calculated by the SOH computation unit. Then, an internal resistance computing determination unit calculates an index indicating a polarization voltage of the battery, and determines whether the index is equal to or more than a determination threshold. When the internal resistance computing determination unit determines that the index is equal to or more than the determination threshold, the battery is controlled on the basis of the internal resistance value calculated when the index is less than a determination threshold before the determination.
    Type: Grant
    Filed: April 7, 2017
    Date of Patent: March 23, 2021
    Assignee: Vehicle Energy Japan Inc.
    Inventors: Ryohhei Nakao, Keiichiro Ohkawa
  • Patent number: 10879570
    Abstract: A current of a storage battery is appropriately controlled depending on the situation. In a battery controller, a battery information acquiring unit acquires information on the storage battery. A first allowable current calculating unit calculates a first allowable current of a battery module in accordance with a rated value of a component through which a current flows by charging or discharging of the battery module. A second allowable current calculating unit calculates a second allowable current of the battery module in accordance with an SOC of the battery module on the basis of the information acquired by the battery information acquiring unit. A third allowable current calculating unit calculates a third allowable current of the battery module in accordance with an SOH of the battery module on the basis of the information acquired by the battery information acquiring unit.
    Type: Grant
    Filed: August 8, 2016
    Date of Patent: December 29, 2020
    Assignee: Vehicle Energy Japan Inc.
    Inventors: Shin Yamauchi, Kei Sakabe, Masahiro Yonemoto, Takanori Yamazoe, Keiichiro Ohkawa, Ryohhei Nakao
  • Patent number: 10845417
    Abstract: A battery management device includes an SOCv calculation unit that calculates a state of charge using voltage across both ends of a battery, an SOCi calculation unit calculates a state of charge by integrating currents flowing in the battery, and an SOCw calculation unit performs weighted addition of the battery's state of charges calculated by the SOCv and the SOCi calculation unit. An SOCi biased time calculation unit calculates an SOCi biased time based on one or a plurality of elapsed time from the end of a previous system operation or the end of charging or discharging during the previous system operation to the start of the current system, temperature, degree of degradation, and polarization voltage of the battery. The SOCw increases a weight of the state of charge of the battery calculated by the SOCi calculation while the elapsed time from the activation is within the SOCi biased time.
    Type: Grant
    Filed: January 10, 2017
    Date of Patent: November 24, 2020
    Assignee: VEHICLE ENERGY JAPAN, INC.
    Inventors: Yohei Nakamura, Keiichiro Ohkawa
  • Patent number: 10840722
    Abstract: An object of the present invention is to provide a control device and a control method for a storage battery, which calculates an appropriate maximum allowable input/output power that suppresses deterioration of the storage battery while suppressing deterioration of power performance of a vehicle when a current is continuously charged or discharged. When it is detected that charging or discharging is continuously performed over a predetermined duration time with respect to the maximum allowable charge power and the maximum allowable discharge power which can be input and output during the calculated predetermined duration time, the value of the maximum allowable charge power or the maximum allowable discharge power communicated to a vehicle controller on the basis of the state of charge or discharge is reduced based on the time during which charging or discharging is actually continued.
    Type: Grant
    Filed: December 22, 2016
    Date of Patent: November 17, 2020
    Assignee: VEHICLE ENERGY JAPAN, INC.
    Inventors: Keiichiro Ohkawa, Yoshinori Aoshima
  • Patent number: 10818983
    Abstract: Provided is a battery management device capable of effectively utilizing battery performance while securing battery life. The battery management device includes: a divergence amount calculation unit that calculates a divergence amount between a life target value or a degradation amount target value of a storage battery, which is a secondary battery, and a life prediction value or a degradation amount prediction value according to use history of the storage battery in an arbitrary period; and a limit value change unit that changes charge/discharge limit values for controlling degradation of the storage battery based on the divergence amount. The limit value change unit includes a first limit value calculation unit that calculates a first limit value set that is a combination of the charge/discharge limit values for each of a plurality of types of control parameters that change in correlation with each other based on the divergence amount.
    Type: Grant
    Filed: August 8, 2016
    Date of Patent: October 27, 2020
    Assignee: VEHICLE ENERGY JAPAN, INC.
    Inventors: Masahiro Yonemoto, Kei Sakabe, Takanori Yamazoe, Shin Yamauchi, Keiichiro Ohkawa, Ryohhei Nakao
  • Patent number: 10807494
    Abstract: The state of internal resistance is appropriately expressed for a battery being energized. A battery management system includes a battery information acquisition section, a voltage calculation section, a current fluctuation amount calculation section 109 and a resistance correction amount calculation section. The battery information acquisition section acquires a voltage value V of a storage battery being energized. The voltage calculation section acquires a predicted battery voltage value Vmodel of the storage battery being energized by a method different from that of the battery information acquisition section. The current fluctuation amount calculation section calculates a current fluctuation amount dI/dt of the storage battery per unit time.
    Type: Grant
    Filed: February 1, 2017
    Date of Patent: October 20, 2020
    Assignee: Vehicle Energy Japan Inc.
    Inventors: Masahiro Yonemoto, Kei Sakabe, Ryohhei Nakao, Keiichiro Ohkawa, Daiki Komatsu
  • Patent number: 10804722
    Abstract: An object of the present invention is to provide a control device and a control method for a storage battery, which calculates an appropriate maximum allowable input/output power that suppresses deterioration of the storage battery while suppressing deterioration of power performance of a vehicle when a current is continuously charged or discharged. When it is detected that charging or discharging is continuously performed over a predetermined duration time with respect to the maximum allowable charge power and the maximum allowable discharge power which can be input and output during the calculated predetermined duration time, the value of the maximum allowable charge power or the maximum allowable discharge power communicated to a vehicle controller on the basis of the state of charge or discharge is reduced based on the time during which charging or discharging is actually continued.
    Type: Grant
    Filed: December 22, 2016
    Date of Patent: October 13, 2020
    Assignee: VEHICLE ENERGY JAPAN, INC.
    Inventors: Keiichiro Ohkawa, Yoshinori Aoshima