DYNAMIC ESTIMATION OF CELL CORE TEMPERATURE BY SIMPLE EXTERNAL MEASUREMENTS

• US 20110299564A1
• Filed: 05/20/2011
• Published: 12/08/2011
• Est. Priority Date: 05/26/2010
• Status: Active Grant

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations LLC (General Motors Company)
• Inventors: Leutheuser, Andrew H., Liu, Wei, Franchett, Mark E., Kenkre, Mahendra M., Dudley, Paul J., Nolte, Jason J., Hua, Charles
• Granted Patent: US 8,529,125 B2
• Time in Patent Office: Days
• US Class Current: 374/134
• CPC Class Codes: G01K 7/427 Temperature calculation based on spatial modeling, e.g. spatial inter- or extrapolation
• CPC Class Codes: H01M 10/443 in response to temperature
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

Methods and systems for dynamically estimating the core temperature of at least one cell in a battery during an operative period. The method includes receiving by at least one controller the surface temperature, the current, the voltage, the state of charge, and the period of time from the initiation of a rest period to the termination of the rest period, determining an initial value of the lumped internal resistance of the at least one cell, determining subsequent values of the lumped internal resistance recursively in real-time based on the initial value, the current, and the voltage, and determining the core temperature of the at least one cell based on the surface temperature, the current, the obtained time, and the lumped internal resistance. The system for dynamically estimating the core temperature of the cells in a battery includes a plurality of sensors configured to transmit signals related to surface temperature, current, and voltage of the battery, a timing device configured to transmit signals related to the period of time from the initiation of a rest period to the termination of the rest period, and a control system, wherein the control system comprises a memory device and a controller.

Claims

1. A method for dynamically estimating the core temperature of at least one cell in a battery during an operative period, the method comprising:

receiving by at least one controller the surface temperature of the at least one cell, the current of the at least one cell, the voltage of the at least on cell, the state of charge of the at least one cell, and the period of time from the initiation of a rest period to the termination of the rest period;

determining an initial value of the lumped internal resistance of the at least one cell;

determining subsequent values of the lumped internal resistance recursively in real-time based on the initial value, the current, and the voltage; and

determining the core temperature of the at least one cell based on the surface temperature, the current, the obtained time, and the lumped internal resistance.

2. The method of claim 1, wherein the core temperature is determined independent of at least one of cooling air temperature, cooling air flow rate, and fan speed of the battery.

3. The method of claim 1, wherein the subsequent values of the lumped internal resistance are determined recursively in real-time via a least squares relationship.

4. The method of claim 1, wherein the initial value is determined at the termination of the rest period based on the surface temperature and the state of charge.

5. The method of claim 1, further comprising limiting the surface temperature to a predetermined value range.

6. The method of claim 1, further comprising filtering at least one of the surface temperature, the voltage, and the current via a low-pass filter method.

7. The method of claim 1, further comprising filtering the surface temperature via a moving average method.

8. The method of claim 1, further comprising updating the determined core temperature at a periodic time interval.

9. The method of claim 8, wherein the periodic time interval comprises about 25 ms.

10. The method of claim 1, further comprising storing temperature information of the at least one cell wherein one or more of the at least one cell faults.

11. The method of claim 1, wherein the determined core temperature of the at least one cell is characterized by the following relationship:

12. A system for dynamically estimating the core temperature of at least one cell in a battery in a vehicle during an operative period, wherein the vehicle receives at least a portion of its power from the battery, the system comprising:

a plurality of sensors configured to transmit signals related to at least one of surface temperature, current, and voltage of the battery;

a timing device configured to transmit signals related to the period of time from the initiation of a rest period to the termination of the rest period;

a control system in signal communication with the plurality of sensors and the timing device, wherein the control system comprises a memory device and a controller in signal communication with the memory device with instructions for dynamically estimating the core temperature of at least one cell in a battery during an operative period and subsequent to a rest period, the instructions being written to;

receive the surface temperature of the at least one cell, the current of the at least one cell, the voltage of the at least one cell, the state of charge of the at least one cell, the period of time from the initiation of the rest period to the termination of the rest period;

determine an initial value of the lumped internal resistance of the at least one cell; and

determine subsequent values of the lumped internal resistance recursively in real-time based on the initial value, the current, and the voltage; and

determine the core temperature of the at least one cell based on the surface temperature, the current, the obtained time, and the lumped internal resistance.

13. The system of claim 12, wherein the core temperature is determined independent of at least one of cooling air temperature, cooling air flow rate, and fan speed of the battery.

14. The system of claim 12, wherein the initial value is determined at the termination of the rest period based on the surface temperature and the state of charge

15. The system of claim 12, wherein the instructions are further written to limit at least one of the surface temperature and the estimated lumped internal resistance.

16. The system of claim 12, wherein the instructions are further written to filter at least one of the surface temperature, the voltage, and the current.

17. The system of claim 12, wherein the instructions are written to update the determined core temperature at a periodic time interval.

18. The system of claim 12, wherein the instructions are further written to store temperature information of the at least one cell wherein one or more of the at least one cell faults.

19. The system of claim 12, wherein the instructions are written to determine the core temperature of the at least one cell in accordance with the following relationship:

20. A vehicle incorporating the system of claim 12.