Method and apparatus for controlling cooling and detecting abnormality in battery pack system

• US 20030087148A1
• Filed: 11/05/2002
• Published: 05/08/2003
• Est. Priority Date: 11/06/2001
• Status: Active Grant

• Current Assignee: Panasonic EV Energy Company, Limited (Toyota Motor Corporation)
• Original Assignee: Panasonic EV Energy Company, Limited (Toyota Motor Corporation)
• Inventors: Minamiura, Keiichi
• Granted Patent: US 6,903,534 B2
• Time in Patent Office: Days
• US Class Current: 429/62
• CPC Class Codes: H01M 10/44 Methods for charging or discharging circuits for charging H02J7/00
• CPC Class Codes: H01M 10/482 for several batteries or cells simultaneously or sequentially
• CPC Class Codes: H01M 10/613 Cooling or keeping cold
• CPC Class Codes: H01M 10/633 characterised by algorithms, flow charts, software details or the like
• CPC Class Codes: H01M 10/6563 with forced flow, e.g. by blowers
• CPC Class Codes: H01M 2200/10 Temperature sensitive devices
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

When an SOC difference between battery pack blocks exceeds a threshold, or a temperature difference between the battery pack blocks exceeds a threshold, a control section changes cooling modes and cooling control maps for cooling fans of respective battery pack blocks to reduce variation in SOC and in temperature difference, thereby improving charging efficiency, and making degradation rates even, so that the life of the total battery pack system is extended.

Claims

1. A method for controlling cooling in a battery pack system, the battery pack system being composed of a plurality of battery pack blocks connected with one another in series, in parallel, or by a combination of serial connection and parallel connection, each of the battery pack blocks being constituted by connecting a plurality of cells in series, the method comprising:

cooling each of the battery pack blocks in a cooling mode selected from a plurality of cooling modes for each battery pack block; and

controlling the system so that an SOC difference between the battery pack blocks is made equal to or smaller than a threshold, when an SOC difference between one battery pack block and another battery pack block exceeds the threshold, by switching a cooling mode of the one battery pack block.

2. The method for controlling cooling in a battery pack system according to claim 1, further comprising switching a cooling mode of a battery pack block with a higher SOC to a cooling mode with a lower cooling capacity under a condition that a battery temperature is not exceeding a predetermined temperature.

5. A method for controlling cooling in a battery pack system, the method comprising:

controlling an SOC difference between battery pack blocks in accordance with the method for controlling cooling in a battery pack system according to claim 1 so as to make the difference equal to or smaller than a threshold; and

controlling a temperature difference between the battery pack blocks in accordance with the method for controlling cooling in a battery pack system according to claim 3 so as to make the temperature difference equal to or smaller than a threshold.

3. A method for controlling cooling in a battery pack system, the battery pack system being composed of a plurality of battery pack blocks connected with one another in series, in parallel, or by a combination of serial connection and parallel connection, each of the battery pack blocks being constituted by connecting a plurality of cells in series, the method comprising:

cooling each of the battery pack blocks in accordance with a control map selected from a plurality of control maps for each battery pack block; and

controlling the system so that a temperature difference between the battery pack blocks is made equal to or smaller than a threshold, when a temperature difference between one battery pack block and another battery pack block exceeds the threshold, by changing the control map for use in cooling the one battery pack block.

4. The method for controlling cooling in a battery pack system according to claim 3, further comprising changing a control map of a cooling unit of a battery pack block with a higher temperature to a control map with a higher cooling capacity.

6. A method for detecting an abnormality in a battery pack system, the battery pack system being composed of a plurality of battery pack blocks connected with one another in series, in parallel, or by a combination of serial connection and parallel connection, each of the battery pack blocks being constituted by connecting a plurality of cells in series, the method comprising:

detecting, as an abnormality, a temperature difference between one battery pack block and another battery pack block exceeding a threshold.

7. The method for detecting an abnormality in a battery pack system according to claim 6, wherein, when the temperature difference between the one battery pack block and the other battery pack block exceeds the threshold, a control map for cooling the one battery pack block is changed, and when the temperature difference exceeds the threshold even with a cooling according to a control map with a highest cooling capability, an abnormality is detected.

8. An apparatus for controlling cooling in a battery pack system, the battery pack system being composed of a plurality of battery pack blocks connected with one another in series, in parallel, or by a combination of serial connection and parallel connection, each of the battery pack blocks being constituted by connecting a plurality of cells in series, the apparatus comprising a control section, wherein each of the battery pack blocks is provided with an SOC detecting unit and a cooling unit, and the control section controls respective cooling units by selecting one of a plurality of cooling modes for each cooling unit, and, if an SOC difference between one battery pack block and another battery pack block exceeds a threshold, the control section controls the cooling unit of the one battery pack block by changing the cooling mode thereof.

9. An apparatus for controlling cooling in a battery pack system, the battery pack system being composed of a plurality of battery pack blocks connected with one another in series, in parallel, or by a combination of serial connection and parallel connection, each of the battery pack blocks being constituted by connecting a plurality of cells in series, the apparatus comprising a control section, wherein each of the battery pack blocks is provided with a temperature detecting unit and a cooling unit, and the control section controls respective cooling units by selecting one of a plurality of control maps for each cooling unit, and, if a temperature difference between one battery pack block and another battery pack block exceeds a threshold, the control section controls the cooling unit of the one battery pack block by changing the control map thereof.

10. The apparatus for controlling cooling in a battery pack system according to claim 9, wherein the control section detects, as an abnormality, a temperature difference exceeding the threshold even with cooling according to a control map with a highest cooling capacity.

11. An apparatus for detecting an abnormality in a battery pack system, the battery pack system being composed of a plurality of battery pack blocks connected with one another in series, in parallel, or by a combination of serial connection and parallel connection, each of the battery pack blocks being constituted by connecting a plurality of cells in series, the apparatus comprising an abnormality detection section, wherein each of the battery pack blocks is provided with a temperature detecting unit and a cooling unit, and the abnormality detection section detects, as an abnormality, a temperature difference between one battery pack block and another battery pack block exceeding a threshold.