Battery system and method of operating the battery system

• US 9,539,963 B2
• Filed: 01/17/2013
• Issued: 01/10/2017
• Est. Priority Date: 03/23/2012
• Status: Active Grant

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Kageyama, Tomomi, Kobayashi, Hiroyuki, Nomura, Fujio
• Primary Examiner(s): Barnie, Rexford
• Assistant Examiner(s): DHILLON, JAGDEEP S
• Application Number:
  US13/743,587
• Publication Number:
  US 20130249278A1
• Time in Patent Office: 1,454 Days
• Field of Search: 307/9.1, 307 101-107, 307/80, 307/86, 307/43, 307/109, 320/109, 320/101.103, 320/116, 320/118
• US Class Current: 1/1
• CPC Class Codes: B60R 16/033 characterised by the use of electrical cells or batteries for propulsion puposes B60K1/04; supplying batteries to, or removing batteries from, vehicles B60S5/06; testing of charge state G01R31/36
• CPC Class Codes: H01M 10/052 Li-accumulators
• CPC Class Codes: H01M 10/4207 for several batteries or cells simultaneously or sequentially
• CPC Class Codes: H01M 10/482 for several batteries or cells simultaneously or sequentially
• CPC Class Codes: H01M 10/488 Cells or batteries combined with indicating means for external visualization of the condition, e.g. by change of colour or of light density
• CPC Class Codes: H01M 2010/4271 Battery management systems including electronic circuits, e.g. control of current or voltage to keep battery in healthy state, cell balancing
• CPC Class Codes: H01M 2010/4278 Systems for data transfer from batteries, e.g. transfer of battery parameters to a controller, data transferred between battery controller and main controller
• CPC Class Codes: H02J 7/0013 acting upon several batteries simultaneously or sequentially H02J7/1423 takes precedence
• CPC Class Codes: H02J 7/0024 Parallel/serial switching of connection of batteries to charge or load circuit
• CPC Class Codes: H02J 7/0047 with monitoring or indicating devices or circuits
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries

Abstract

In a battery system for use in a vehicle as power supply, a plurality of battery groups, each configured to output a rated voltage while being charged, in parallel to an input/output system line by a system connection device, BMU devices monitor the battery groups, respectively, determining whether the battery groups enter an abnormal state, and any battery group entering the abnormal state is designated and disconnected from the input/output system line. If a predetermined of battery groups are found to enter an abnormal state, as determined by the BMU devices, a system controller generates an alarm, informing the user that the battery system may not provide power in the required amount.

Claims

1. A battery system for use in a vehicle as power supply, the system comprising:

a plurality of battery groups connected in parallel to one another and individually connected to an input/output system line, each of the battery groups being configured to output a rated voltage while being charged, and including a defined number of battery modules connected in series;

a plurality of coupling switches at respective ones of the battery groups, each of the plurality of coupling switches being configured to disconnect a corresponding battery group from the input/output system line in accordance with a control signal of disconnection; and

a plurality of monitoring controllers at the respective ones of the battery groups, each of the monitoring controllers being configured to issue the control signal of disconnection to a corresponding one of the coupling switches at a respective one of the battery groups,

each of the battery modules comprising a defined number of serially connected battery cells and a cell monitoring unit configured to monitor an operation state of the serially connected battery cells, and

each of the monitoring controllers being configured to be notified from a corresponding one of the cell monitoring units of the operation state of the serially connected battery cells in a corresponding one of the battery groups, to determine, based on the notified operation state, whether the corresponding one of the battery groups enters an abnormal state, and to disconnect the corresponding one of the battery groups from the input/output system line upon determining that the corresponding one of the battery groups is in the abnormal state.

2. The battery system of claim 1, further comprising a plurality of backflow preventing devices provided between the battery groups and the input/output system line, the backflow preventing devices configured to prevent a backflow of a current from the input/output system line to the battery group when any battery group is disconnected in accordance with the control signal.

3. The battery system of claim 1, further comprising a system controller configured to cause a monitor to display a monitoring result of each of the monitoring controllers.

4. The battery system of claim 1, further comprising a system controller configured to generate an alarm when more battery groups than a prescribed number are found to enter the abnormal state based on a monitoring result of each of the monitoring controllers.

5. The battery system of claim 1, wherein each of the battery cells is a lithium ion cell.

7. The battery system of claim 1, wherein any battery group entering the abnormal state and therefore disconnected is replaced by a new one after the output voltage of the battery group has been adjusted to the output voltage of any battery group in the normal state.

6. A method of operating a battery system installed in a vehicle as power supply and comprising a plurality of battery groups connected in parallel to one another and individually connected to an input/output system line, each of the battery groups configured to output a rated voltage while being charged,

each of the battery groups comprising a defined number of battery modules connected in series, a coupling switch configured to break a connection with the input/output system line in accordance with a control signal of disconnection, and a monitoring controller configured to issue the control signal of disconnection to the coupling switch,

each of the battery modules comprising a defined number of serially connected battery cells and a cell monitoring unit configured to monitor an operation state of the serially connected battery cells,

the method comprising:

controlling the cell monitoring unit in each of the battery modules to monitor the operation state of the battery cells in each of the battery modules; and

controlling every one of the monitoring controllers to determine whether a corresponding one of the battery cell groups enters an abnormal state, and to issue the control signal of disconnection to a corresponding one of the coupling switches upon determining that the battery group concerned is in the abnormal state, thereby disconnecting the battery group concerned from the input/output system line.