Battery system for vehicle, on-vehicle battery module, and cell controller

• US 9,333,874 B2
• Filed: 03/18/2015
• Issued: 05/10/2016
• Est. Priority Date: 01/29/2008
• Status: Active Grant

• Current Assignee: Hitachi Automotive Systems Limited (Hitachi, Ltd.), Hitachi, Ltd.
• Original Assignee: Hitachi Automotive Systems Limited (Hitachi, Ltd.), Hitachi, Ltd.
• Inventors: Kubo, Kenji, Kudo, Akihiko, Kikuchi, Mutsumi, Emori, Akihiko
• Primary Examiner(s): Zanelli, Michael J
• Application Number:
  US14/661,412
• Publication Number:
  US 20150191102A1
• Time in Patent Office: 419 Days
• US Class Current: 1/1
• CPC Class Codes: B60L 50/64 Constructional details of batteries specially adapted for electric vehicles
• CPC Class Codes: B60L 58/19 Switching between serial connection and parallel connection of battery modules
• CPC Class Codes: B60L 58/22 Balancing the charge of battery modules
• CPC Class Codes: G01R 19/16542 for batteries charge condition monitoring in G01R31/36
• CPC Class Codes: G01R 31/36 Arrangements for testing, measuring or monitoring the electrical condition of accumulators or electric batteries, e.g. capacity or state of charge [SoC]
• CPC Class Codes: G01R 31/388 involving voltage measurements
• CPC Class Codes: G01R 31/396 Acquisition or processing of data for testing or for monitoring individual cells or groups of cells within a battery
• CPC Class Codes: G01R 31/54 Testing for continuity
• CPC Class Codes: G01R 35/00 Testing or calibrating of apparatus covered by the other groups of this subclass
• CPC Class Codes: H02J 7/0016 using shunting, discharge or bypass circuits
• CPC Class Codes: H02J 7/0019 using switched or multiplexed charge circuits
• CPC Class Codes: H02J 7/00302 Overcharge protection
• CPC Class Codes: H02J 7/00306 Overdischarge protection
• CPC Class Codes: H02J 7/00309 Overheat or overtemperature protection
• CPC Class Codes: H02J 7/0048 Detection of remaining charge capacity or state of charge [SOC]
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 90/16 Information or communication technologies improving the operation of electric vehicles

Abstract

A battery system for vehicle comprises a battery unit that is constituted with a plurality of serially connected cell groups each include a plurality of serially connected battery cells, integrated circuits that are each disposed in correspondence to one of the cell groups of the battery unit and each measure terminal voltages at the battery cells in the corresponding cell group, and a signal transmission path through which one of the integrated circuits is connected to another one of the integrated circuits or to a circuit other than that of the integrated circuits.

Claims

1. A battery system, comprising:

a battery module that includes a plurality of battery cells which are electrically connected in series;

a voltage measurement circuit that measures a terminal voltage of each of the plurality of battery cells; and

a diagnosis circuit that diagnoses an abnormality in a circuit, wherein;

the voltage measurement circuit includes

a selection circuit that selects a terminal voltage of a battery cell to be measured from among terminal voltages of the plurality of battery cells,

a pull-up circuit that pulls up a potential at an output terminal of the selection circuit to a high potential, and

a pull-down circuit that pulls down a potential at the output terminal of the selection circuit to a low potential; and

the diagnosis circuit

diagnoses whether or not a plurality of switches constituting the selection circuit are all in an open state when the plurality of switches constituting the selection circuit were all to be in an open state, based on whether or not a relationship between a threshold value and a voltage of the output terminal of the selection circuit, which has been measured by the voltage measurement circuit in a pulled-up state or pulled-down state, meets a relationship when the plurality of switches constituting the selection circuit are all in an open state, and then

diagnoses whether or not a battery cell to be measured is selected by a specific switch of the plurality of switches constituting the selection circuit when the specific switch was to be in a closed state, based on whether or not a relationship between a threshold value and a voltage of the output terminal of the selection circuit, which has been measured by the voltage measurement circuit in a pulled-up state or pulled-down state, meets a relationship when the specific switch is in a closed state.

2. The battery system according to claim 1, wherein:

the pull-up circuit and the pull-down circuit are operated in a period corresponding to a measurement period in which the voltage measurement circuit measures the terminal voltage of each of the plurality of battery cells.

3. The battery system according to claim 1, wherein:

the pull-up circuit and the pull-down circuit are provided to respectively correspond to two output terminals of the selection circuit.

4. The battery system according to claim 1, wherein:

the pull-up circuit and the pull-down circuit are operated in a period corresponding to a measurement period in which the voltage measurement circuit measures the terminal voltage of each of the plurality of battery cells, and are provided to respectively correspond to two output terminals of the selection circuit.

5. A battery monitoring device, comprising:

a voltage measurement circuit that measures a terminal voltage of each of a plurality of battery cells which are electrically connected in series; and

a diagnosis circuit that diagnoses an abnormality in a circuit, wherein;

the voltage measurement circuit includes

a selection circuit that selects a terminal voltage of a battery cell to be measured from among terminal voltages of the plurality of battery cells,

a pull-up circuit that pulls up a potential at an output terminal of the selection circuit to a high potential, and

a pull-down circuit that pulls down a potential at the output terminal of the selection circuit to a low potential;

the diagnosis circuit

diagnoses whether or not a plurality of switches constituting the selection circuit are all in an open state when the plurality of switches constituting the selection circuit were all to be in an open state, based on whether or not a relationship between a threshold value and a voltage of the output terminal of the selection circuit, which has been measured by the voltage measurement circuit in a pulled-up state or pulled-down state, meets a relationship when the plurality of switches constituting the selection circuit are all in an open state, and then

diagnoses whether or not a battery cell to be measured is selected by a specific switch of the plurality of switches constituting the selection circuit when the specific switch was to be in a closed state, based on whether or not a relationship between a threshold value and a voltage of the output terminal of the selection circuit, which has been measured by the voltage measurement circuit in a pulled-up state or pulled-down state, meets a relationship when the specific switch is in a closed state.

6. The battery monitoring device according to claim 5, wherein:

the pull-up circuit and the pull-down circuit are operated in a period corresponding to a measurement period in which the voltage measurement circuit measures the terminal voltage of each of the plurality of battery cells.

7. The battery monitoring device according to claim 5, wherein:

the pull-up circuit and the pull-down circuit are provided to respectively correspond to two output terminals of the selection circuit.

8. The battery monitoring device according to claim 5, wherein:

the pull-up circuit and the pull-down circuit are operated in a period corresponding to a measurement period in which the voltage measurement circuit measures the terminal voltage of each of the plurality of battery cells, and are provided to respectively correspond to two output terminals of the selection circuit.