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: 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
  • Publication number: 20200280204
    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: Application
    Filed: May 18, 2020
    Publication date: September 3, 2020
    Applicant: VEHICLE ENERGY JAPAN, INC.
    Inventors: Kei SAKABE, Keiichiro OHKAWA, Takanori YAMAZOE, Ryohhei NAKAO, Masahiro YONEMOTO
  • Patent number: 10725111
    Abstract: A battery state detection device detects a battery state and includes: a first permissible current calculating unit configured to calculate a first permissible current of a battery based on a voltage of the battery detected by a voltage detecting unit; a second permissible current calculating unit configured to calculate a second permissible current of the battery without using the voltage of the battery; and a correction unit configured to compare the first permissible current and the second permissible current and to perform a predetermined correction process on the basis of the comparison result.
    Type: Grant
    Filed: June 12, 2015
    Date of Patent: July 28, 2020
    Assignee: Vehicle Energy Japan Inc.
    Inventors: Youhei Kawahara, Masahiro Yonemoto, Keiichiro Ohkawa
  • Patent number: 10686229
    Abstract: A battery state detection device detects a battery state and includes: a first permissible current calculating unit configured to calculate a first permissible current of a battery based on a voltage of the battery detected by a voltage detecting unit; a second permissible current calculating unit configured to calculate a second permissible current of the battery without using the voltage of the battery; and a permissible current determining unit configured to determine a permissible current of the battery corresponding to the battery state on the basis of at least one of the first permissible current and the second permissible current.
    Type: Grant
    Filed: June 12, 2015
    Date of Patent: June 16, 2020
    Assignee: Vehicle Energy Japan Inc.
    Inventors: Youhei Kawahara, Masahiro Yonemoto, Keiichiro Ohkawa
  • Patent number: 10680453
    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: April 27, 2016
    Date of Patent: June 9, 2020
    Assignee: HITACHI AUTOMOTIVE SYSTEMS, LTD.
    Inventors: Kei Sakabe, Keiichiro Ohkawa, Takanori Yamazoe, Ryohhei Nakao, Masahiro Yonemoto
  • Patent number: 10591550
    Abstract: A secondary-battery monitoring device includes: a use-state memory device that stores a transition of a load parameter indicating a use state of a secondary battery; and a battery capacity prediction device that predicts a temporal change of a battery capacity of the secondary battery on the basis of a prediction function. The prediction function is derived from a relation between growth of a film formed in an electrode surface of the secondary battery and a reduction of a precursor component of the film which is contained in an electrolyte of the secondary battery. The battery capacity prediction device determines a coefficient of the prediction function on the basis of the transition of the load parameter which is stored in the use-state memory device, and predicts the temporal change of the battery capacity of the secondary battery on the basis of the prediction function which uses the coefficient.
    Type: Grant
    Filed: April 28, 2015
    Date of Patent: March 17, 2020
    Assignee: VEHICLE ENERGY JAPAN INC.
    Inventors: Masahiro Yonemoto, Youhei Kawahara, Takeshi Inoue, Keiichiro Ohkawa
  • Patent number: 10589732
    Abstract: A device for controlling current for charging/discharging a battery with a high accuracy includes a time-point setting unit which calculates a voltage difference by subtracting a calculated open-circuit voltage from a measured closed-circuit voltage, and sets first and second time points, at which an absolute value of the voltage difference becomes equal to or less than a predetermined value and an absolute value of a difference in the open-circuit voltage becomes equal to or less than a predetermined value. The control device further includes a current correction amount calculation unit to obtain the current integral amount, calculate the current error in a detection signal and set the current error as the current correction amount on the basis of the current integral amount and the time from the first time point to the second time point. The current correction unit corrects the detection signal using the current correction amount.
    Type: Grant
    Filed: February 26, 2016
    Date of Patent: March 17, 2020
    Assignee: VEHICLE ENERGY JAPAN INC.
    Inventors: Keiichiro Ohkawa, Ryohhei Nakao
  • Publication number: 20190288344
    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: Application
    Filed: April 7, 2017
    Publication date: September 19, 2019
    Applicant: Hitachi Automotive Systems, Ltd.
    Inventors: Ryohhei NAKAO, Keiichiro OHKAWA
  • Publication number: 20190242948
    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: Application
    Filed: July 28, 2017
    Publication date: August 8, 2019
    Applicant: HITACHI AUTOMOTIVE SYSTEMS, LTD.
    Inventors: Daiki KOMATSU, Kei SAKABE, Masahiro YONEMOTO, Shin YAMAUCHI, Keiichiro OHKAWA, Ryohhei NAKAO
  • Publication number: 20190207406
    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: Application
    Filed: February 6, 2018
    Publication date: July 4, 2019
    Inventors: Fanny MATTHEY, Shin YAMAUCHI, Kei SAKABE, Ryohhei NAKAO, Daiki KOMATSU, Keiichiro OHKAWA
  • Patent number: 10266063
    Abstract: A battery controller capable of increasing the number of chances of being able to acquire information on a secondary battery storage capacity and a vehicle system having the battery controller mounted thereon are provided. A battery controller 120 mounted on a vehicle system 200 includes a time point setting unit 153 that sets a first time point at which a first voltage difference dVa (=CCVa?OCVa) which is a difference obtained by subtracting a first open-circuit voltage OCVa from a first closed-circuit voltage CCVa is obtained and a second time point at which a second voltage difference dVb (=CCVb?OCVb) which is a difference obtained by subtracting a second open-circuit voltage OCVb from a second closed-circuit voltage CCVb is obtained and an absolute value of the difference from the first voltage difference dVa is equal to or smaller than a predetermined value.
    Type: Grant
    Filed: February 26, 2016
    Date of Patent: April 23, 2019
    Assignee: HITACHI AUTOMOTIVE SYSTEMS, LTD.
    Inventors: Keiichiro Ohkawa, Ryohhei Nakao
  • Publication number: 20190067954
    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: Application
    Filed: December 22, 2016
    Publication date: February 28, 2019
    Applicant: HITACHI AUTOMOTIVE SYSTEMS, LTD.
    Inventors: Keiichiro OHKAWA, Yoshinori AOSHIMA
  • Patent number: 10209317
    Abstract: A battery monitoring device includes: a current detection unit that detects an electric current flowing through a battery; a voltage detection unit that detects a voltage between both ends of the battery; a temperature detection unit that detects the temperature of the battery; an internal resistance increase rate calculation unit that calculates the internal resistance increase rate of the battery based on the detected electric current, voltage between the both ends, and temperature; and a calculation invalid time setting unit that sets a predetermined calculation invalid time according to the characteristics of the internal resistance increase rate. The calculation results of the internal resistance increase rate is invalidated for an invalid period from the start of charging or discharging of the battery to the lapse of the calculation invalid time.
    Type: Grant
    Filed: May 23, 2013
    Date of Patent: February 19, 2019
    Assignee: Hitachi Automotive Systems, Ltd.
    Inventors: Keiichiro Ohkawa, Naoyuki Igarashi