Battery pack and control method therefor

• US 8,203,306 B2
• Filed: 06/16/2009
• Issued: 06/19/2012
• Est. Priority Date: 06/24/2008
• Status: Active Grant

• Current Assignee: Murata Manufacturing Co Limited
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Nishiyama, Shoichi, Hiratsuka, Masaru, Suzuki, Hiroyuki, Tanaka, Takehiko
• Primary Examiner(s): Berhanu, Samuel
• Application Number:
  US12/485,120
• Publication Number:
  US 20090315520A1
• Time in Patent Office: 1,099 Days
• Field of Search: 320/112, 320/132, 320/134, 320/136, 324426-434
• US Class Current: 320/112
• CPC Class Codes: G01R 19/16542 for batteries charge condition monitoring in G01R31/36
• 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: H01M 10/48 Accumulators combined with arrangements for measuring, testing or indicating the condition of cells, e.g. the level or density of the electrolyte constructional details of current conducting connections for detecting conditions inside cells or batteries, e.g. details of voltage sensing terminals, H01M50/569
• CPC Class Codes: H01M 10/482 for several batteries or cells simultaneously or sequentially
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

A battery pack includes one or more cell blocks in which one or more secondary battery cells are connected in series and/or in parallel, and a control section for measuring a voltage of the one or more cell blocks to detect an abnormality of a cell block on the basis of a measurement result. The control section calculates a time differential of the voltage for the one or more cell blocks on the basis of the measured voltage, extracts a first time differential which is maximum and a second time differential which is minimum from the time differentials of the voltage for the one or more cell blocks, and determines that a cell block corresponding to the second time differential is abnormal in a case where a difference between the first time differential and the second time differential is less than a prescribed value.

Claims

1. A battery pack comprising:

one or a plurality of cell blocks in which one or a plurality of secondary battery cells are connected at least are of in series and in parallel; and

a control section for measuring a voltage and a charge current of the one or the plurality of cell blocks to detect an abnormality of a cell block on the basis of a measurement result,

wherein the control section

calculates time differentials of the voltage and the charge current and second-order time differentials of the voltage and the charge current for the one or the plurality of cell blocks on the basis of the measured voltage and charge current;

determines that a cell block is abnormal in a case where the time differential of the voltage is less than a prescribed value, the second-order time differential of the voltage is less than the prescribed value, and the second-order time differential of the charge current is not less than the prescribed value; and

determines that a cell block is abnormal in a case where the time differential of the charge current is more than the prescribed value, the second-order time differential of the charge current is more than the prescribed value, and the second-order time differential of the voltage is not more than the prescribed value.

2. The battery pack according to claim 1, further comprising:

a charge/discharge switch for controlling a charge/discharge current for the cell blocks on the basis of control performed by the control section,

wherein the control section turns off the charge/discharge switch in a case where an abnormality of a cell block is detected.

3. The battery pack according to claim 1, further comprising:

a communication terminal for communication with an external electronic device,

wherein the control section transmits information indicating that an abnormality has been detected to the external electronic device via the communication terminal in a case where an abnormality of a cell block is detected.

4. A battery pack comprising:

one or a plurality of cell blocks in which one or a plurality of secondary battery cells are connected at least one of in series and in parallel; and

a control section for measuring a voltage and a charge current of the one or the plurality of cell blocks to detect an abnormality of a cell block on the basis of a measurement result,

wherein the control section

calculates a time differential of the voltage and second-order time differentials of the voltage and the charge current for the one or the plurality of cell blocks on the basis of the measured voltage and charge current;

extracts a first time differential which is maximum and a second time differential which is minimum from the time differentials of the voltage for the one or the plurality of cell blocks; and

determines that a cell block corresponding to the second time differential is abnormal in a case where a difference between the first time differential and the second time differential is less than a prescribed value, the second-order time differential of the voltage is less than the prescribed value, and the second-order time differential of the charge current is not less than the prescribed value.

5. A control method for a battery pack, comprising:

measuring a voltage and a charge current of one or a plurality of cell blocks in which one or a plurality of secondary battery cells are connected in series and/or in parallel;

calculating time differentials of the voltage and the charge current and second-order time differentials of the voltage and the charge current for the one or the plurality of cell blocks on the basis of the measured voltage and charge current;

determining that a cell block is abnormal in a case where the time differential of the voltage is less than a prescribed value, the second-order time differential of the voltage is less than the prescribed value, and the second-order time differential of the charge current is not less than the prescribed value; and

determining that a cell block is abnormal in a case where the time differential of the charge current is more than the prescribed value, the second-order time differential of the charge current is more than the prescribed value, and the second-order time differential of the voltage is not more than the prescribed value.

6. A control method for a battery pack, comprising:

measuring a voltage and a charge current of one or a plurality of cell blocks in which one or a plurality of secondary battery cells are connected in series and/or in parallel;

calculating a time differential of the voltage and second-order time differentials of the voltage and the charge current for the one or the plurality of cell blocks on the basis of the measured voltage and charge current;

extracting a first time differential which is maximum and a second time differential which is minimum from the time differentials of the voltage for the one or the plurality of cell blocks; and

determining that a cell block corresponding to the second time differential is abnormal in a case where a difference between the first time differential and the second time differential is less than a prescribed value, the second-order time differential of the voltage is less than the prescribed value, and the second-order time differential of the charge current is not less than the prescribed value.