Patents by Inventor Ryouhei Nakao

Ryouhei Nakao 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: 9685807
    Abstract: Provided is a battery control device that can accurately detect a state of charge even if characteristics relating to the state of charge change as a result of battery degradation. This battery control device is provided with map data describing the correspondence relationship between an open-circuit voltage and a state of charge of the battery and outputs different state-of-charge values for the same open-circuit voltage according to the amount of elapsed time.
    Type: Grant
    Filed: January 27, 2014
    Date of Patent: June 20, 2017
    Assignee: HITACHI AUTOMOTIVE SYSTEMS, LTD.
    Inventors: Ryouhei Nakao, Shinji Imai, Keiichiro Ohkawa, Naoyuki Igarashi, Takahiro Soma
  • Patent number: 9641011
    Abstract: A battery control device capable of carrying out current limitation in consideration of constraints on other components than a battery main body is provided. A battery control device according to the invention has an average current table describing an average current allowed for each of plural time window widths, and limits a battery current in accordance with the description.
    Type: Grant
    Filed: June 10, 2011
    Date of Patent: May 2, 2017
    Assignee: HITACHI AUTOMOTIVE SYSTEMS, LTD.
    Inventors: Keiichiro Ohkawa, Ryouhei Nakao, Youhei Kawahara
  • Patent number: 9362759
    Abstract: In a battery device including a battery pack in which a plurality of cells are connected in series, there are provided a battery control circuit or a battery device capable of eliminating a fluctuation in the voltage or charged state which can occur between the cells, or preventing the cells from being maintained in an over-charged state for a long period. A plurality of cell groups each including a plurality of cells are connected in series to form a battery pack. Cell controller is provided to the respective cell groups operate with electricity supplied from the cell groups allocated thereto so as to monitor and control the state of the cells of the cell group. Battery pack controller controls the cell controller based on information from the plurality of cell controller.
    Type: Grant
    Filed: February 28, 2011
    Date of Patent: June 7, 2016
    Assignee: Hitachi Vehicle Energy, Ltd.
    Inventors: Ryouhei Nakao, Youhei Kawahara, Akihiko Kudou, Akihiko Emori, Kei Sakabe
  • Patent number: 9356451
    Abstract: A battery control circuit includes a voltage detection circuit for measuring voltages of electric cells, balancing circuits for balancing the voltages or SOCs of the electric cells, a signal input/output circuit for communicating with the outside, a power supply circuit having two modes: a normal mode and a low consumption mode, and a time management circuit. It receives a signal containing a period of time until the shift of the power supply circuit from the normal mode to the low consumption mode, and stores it in the time management circuit. If a command from the outside has not been sent for a predetermined period of time or when an operation stop command has been sent from the outside, the time management circuit causes the power supply circuit to continuously operate in the normal mode.
    Type: Grant
    Filed: December 20, 2013
    Date of Patent: May 31, 2016
    Assignee: Hitachi Automotive Systems, Ltd.
    Inventors: Youhei Kawahara, Ryouhei Nakao, Akihiko Kudo, Akihiko Emori, Kei Sakabe
  • Patent number: 9293937
    Abstract: An electric storage device includes an assembled battery including a plurality of electric cells connected in series; an assembled battery control unit that estimates internal resistances of the plurality of electric cells, or a magnitude relationship of the internal resistances of the plurality of electric cells; an assembled battery control unit that calculates such a discharge quantity that an SOC after the electric cells have been discharged becomes lower as the internal resistance of the electric cells, which is estimated by the assembled battery control unit, is larger, or as the magnitude relationship of the internal resistances of the electric cells is estimated to be larger by the assembled battery control unit, for each of the electric cells; and electric cell control units that discharge each of the plurality of electric cells on the basis of the discharge quantity calculated by the assembled battery control unit.
    Type: Grant
    Filed: April 18, 2011
    Date of Patent: March 22, 2016
    Assignee: HITACHI AUTOMOTIVE SYSTEMS, LTD.
    Inventors: Youhei Kawahara, Ryouhei Nakao, Akihiko Kudo, Akihiko Emori, Keiichiro Okawa, Yoshinori Aoshima
  • Patent number: 9252602
    Abstract: To satisfactorily carry out balancing even when balancing control is suspended. It is selected according to a condition which of battery cell information (old state information) by the last balancing stored in a storage device and battery cell information (new state information) acquired during a start of this time is used, and the balancing control is performed.
    Type: Grant
    Filed: May 23, 2011
    Date of Patent: February 2, 2016
    Assignee: HITACHI AUTOMOTIVE SYSTEMS, LTD.
    Inventors: Keiichiro Ohkawa, Youhei Kawahara, Ryouhei Nakao
  • Patent number: 9252624
    Abstract: An object of the invention is to provide a battery control apparatus capable of accurately obtaining permissible charging or discharging power in keeping with variation of the internal resistance of a battery. The battery control apparatus of this invention includes an internal resistance table in which the internal resistance value of single cells corresponding to the temperature and state of charge thereof are described in association with each of charging or discharging duration time of the single cells. The battery control apparatus calculates a permissible charging current or a permissible discharging current by using the internal resistance value described in the internal resistance table and controls the charging or discharging of the single cells in accordance with the current value thus obtained.
    Type: Grant
    Filed: June 10, 2011
    Date of Patent: February 2, 2016
    Assignee: HITACHI AUTOMOTIVE SYSTEMS, LTD.
    Inventors: Keiichiro Ohkawa, Ryouhei Nakao, Youhei Kawahara
  • Publication number: 20150357852
    Abstract: Provided is a battery control device that can accurately detect a state of charge even if characteristics relating to the state of charge change as a result of battery degradation. This battery control device is provided with map data describing the correspondence relationship between an open-circuit voltage and a state of charge of the battery and outputs different state-of-charge values for the same open-circuit voltage according to the amount of elapsed time.
    Type: Application
    Filed: January 27, 2014
    Publication date: December 10, 2015
    Applicant: HITACHI AUTOMOTIVE SYSTEMS, LTD.
    Inventors: Ryouhei NAKAO, Shinji IMAI, Keiichiro OHKAWA, Naoyuki IGARASHI, Takahiro SOMA
  • Publication number: 20140217982
    Abstract: To satisfactorily carry out balancing even when balancing control is suspended. It is selected according to a condition which of battery cell information (old state information) by the last balancing stored in a storage device and battery cell information (new state information) acquired during a start of this time is used, and the balancing control is performed.
    Type: Application
    Filed: May 23, 2011
    Publication date: August 7, 2014
    Applicant: Hitachi Vehicle Energy, Ltd.
    Inventors: Keiichiro Ohkawa, Youhei Kawahara, Ryouhei Nakao
  • Publication number: 20140184166
    Abstract: A battery control device capable of carrying out current limitation in consideration of constraints on other components than a battery main body is provided. A battery control device according to the invention has an average current table describing an average current allowed for each of plural time window widths, and limits a battery current in accordance with the description.
    Type: Application
    Filed: June 10, 2011
    Publication date: July 3, 2014
    Inventors: Keiichiro Ohkawa, Ryouhei Nakao, Youhei Kawahara
  • Publication number: 20140184236
    Abstract: A battery control apparatus which can calculate a state of charge of a battery with high accuracy is provided. The battery control apparatus of the invention determines whether or not an open circuit voltage of a battery cell is within a high sensitivity range in which the open voltage of the battery cell changes by a specified amount or more with respect to a change in the state of charge of the battery cell, and if within the high sensitivity range, calculates the state of charge by using a previously held correspondence relation table between the state of charge of the battery and the open voltage, and if not within the high sensitivity range, uses a previous state of charge calculation result stored in a storage part.
    Type: Application
    Filed: June 10, 2011
    Publication date: July 3, 2014
    Applicant: Hitachi Vehicle Energy, Ltd.
    Inventors: Keiichiro Ohkawa, Youhei Kawahara, Ryouhei Nakao
  • Publication number: 20140159671
    Abstract: A battery control circuit includes a voltage detection circuit for measuring voltages of electric cells, balancing circuits for balancing the voltages or SOCs of the electric cells, a signal input/output circuit for communicating with the outside, a power supply circuit having two modes: a normal mode and a low consumption mode, and a time management circuit. It receives a signal containing a period of time until the shift of the power supply circuit from the normal mode to the low consumption mode, and stores it in the time management circuit. If a command from the outside has not been sent for a predetermined period of time or when an operation stop command has been sent from the outside, the time management circuit causes the power supply circuit to continuously operate in the normal mode.
    Type: Application
    Filed: December 20, 2013
    Publication date: June 12, 2014
    Applicant: Hitachi Vehicle Energy, Ltd.
    Inventors: Youhei KAWAHARA, Ryouhei NAKAO, Akihiko KUDO, Akihiko EMORI, Kei SAKABE
  • Patent number: 8736229
    Abstract: A battery control circuit includes a voltage detection circuit for measuring voltages of electric cells, balancing circuits for balancing the voltages or SOCs of the electric cells, a signal input/output circuit for communicating with the outside, a power supply circuit having two modes: a normal mode and a low consumption mode, and a time management circuit. It receives a signal containing a period of time until the shift of the power supply circuit from the normal mode to the low consumption mode, and stores it in the time management circuit. If a command from the outside has not been sent for a predetermined period of time or when an operation stop command has been sent from the outside, the time management circuit causes the power supply circuit to continuously operate in the normal mode.
    Type: Grant
    Filed: June 22, 2011
    Date of Patent: May 27, 2014
    Assignee: Hitachi Vehicle Energy, Ltd.
    Inventors: Youhei Kawahara, Ryouhei Nakao, Akihiko Kudo, Akihiko Emori, Kei Sakabe
  • Publication number: 20140111164
    Abstract: An object of the invention is to provide a battery control apparatus capable of accurately obtaining permissible charging or discharging power in keeping with variation of the internal resistance of a battery. The battery control apparatus of this invention includes an internal resistance table in which the internal resistance value of single cells corresponding to the temperature and state of charge thereof are described in association with each of charging or discharging duration time of the single cells. The battery control apparatus calculates a permissible charging current or a permissible discharging current by using the internal resistance value described in the internal resistance table and controls the charging or discharging of the single cells in accordance with the current value thus obtained.
    Type: Application
    Filed: June 10, 2011
    Publication date: April 24, 2014
    Applicant: Hitachi Vehicle Energy, Ltd.
    Inventors: Keiichiro Ohkawa, Ryouhei Nakao, Youhei Kawahara
  • Publication number: 20140042973
    Abstract: An electric storage device includes an assembled battery including a plurality of electric cells connected in series; an assembled battery control unit that estimates internal resistances of the plurality of electric cells, or a magnitude relationship of the internal resistances of the plurality of electric cells; an assembled battery control unit that calculates such a discharge quantity that an SOC after the electric cells have been discharged becomes lower as the internal resistance of the electric cells, which is estimated by the assembled battery control unit, is larger, or as the magnitude relationship of the internal resistances of the electric cells is estimated to be larger by the assembled battery control unit, for each of the electric cells; and electric cell control units that discharge each of the plurality of electric cells on the basis of the discharge quantity calculated by the assembled battery control unit.
    Type: Application
    Filed: April 18, 2011
    Publication date: February 13, 2014
    Applicant: HITACHI VEHICLE ENERGY, LTD.
    Inventors: Youhei Kawahara, Ryouhei Nakao, Akihiko Kudo, Akihiko Emori, Keiichiro Okawa, Yoshinori Aoshima
  • Publication number: 20130106356
    Abstract: In a battery device including a battery pack in which a plurality of cells are connected in series, there are provided a battery control circuit or a battery device capable of eliminating a fluctuation in the voltage or charged state which can occur between the cells, or preventing the cells from being maintained in an over-charged state for a long period. A plurality of cell groups each including a plurality of cells are connected in series to form a battery pack. Cell controller is provided to the respective cell groups operate with electricity supplied from the cell groups allocated thereto so as to monitor and control the state of the cells of the cell group. Battery pack controller controls the cell controller based on information from the plurality of cell controller.
    Type: Application
    Filed: February 28, 2011
    Publication date: May 2, 2013
    Applicant: Hitachi Vehicle Energy, Ltd.
    Inventors: Ryouhei Nakao, Youhei Kawahara, Akihiko Kudou, Akihiko Emori, Kei Sakabe
  • Publication number: 20110316520
    Abstract: A battery control circuit includes a voltage detection circuit for measuring voltages of electric cells, balancing circuits for balancing the voltages or SOCs of the electric cells, a signal input/output circuit for communicating with the outside, a power supply circuit having two modes: a normal mode and a low consumption mode, and a time management circuit. It receives a signal containing a period of time until the shift of the power supply circuit from the normal mode to the low consumption mode, and stores it in the time management circuit. If a command from the outside has not been sent for a predetermined period of time or when an operation stop command has been sent from the outside, the time management circuit causes the power supply circuit to continuously operate in the normal mode.
    Type: Application
    Filed: June 22, 2011
    Publication date: December 29, 2011
    Applicant: Hitachi Vehicle Energy, Ltd.
    Inventors: Youhei Kawahara, Ryouhei Nakao, Akihiko Kudo, Akihiko Emori, Kei Sakabe