SYSTEM AND METHOD FOR ENERGY PREDICTION IN BATTERY PACKS

• US 20130041538A1
• Filed: 08/09/2012
• Published: 02/14/2013
• Est. Priority Date: 08/12/2011
• Status: Active Grant

• Current Assignee: CPS Technology Holdings, LLC
• Original Assignee: Johnson Controls Technology LLC (Johnson Controls International plc)
• Inventors: Jin, Zhihong H., Elberson, Matthew D., Boone, David R., Kasavajjila, Uday S.
• Granted Patent: US 9,360,527 B2
• Time in Patent Office: Days
• US Class Current: 701/22
• CPC Class Codes: B60L 2240/545 Temperature
• CPC Class Codes: B60L 2240/547 Voltage
• CPC Class Codes: B60L 2240/549 Current
• CPC Class Codes: B60L 2250/16 by display
• CPC Class Codes: B60L 2250/18 by enquiring driving style
• CPC Class Codes: B60L 2260/52 drive range estimation, e.g. of estimation of available travel distance
• CPC Class Codes: B60L 2260/54 Energy consumption estimation
• CPC Class Codes: B60L 50/16 with provision for separate direct mechanical propulsion
• CPC Class Codes: B60L 50/61 by batteries charged by engine-driven generators, e.g. series hybrid electric vehicles
• CPC Class Codes: B60L 50/64 Constructional details of batteries specially adapted for electric vehicles
• CPC Class Codes: B60L 50/66 Arrangements of batteries
• CPC Class Codes: B60L 58/16 responding to battery ageing, e.g. to the number of charging cycles or the state of health [SoH]
• CPC Class Codes: B60L 58/22 Balancing the charge of battery modules
• CPC Class Codes: G01C 21/26 specially adapted for navigation in a road network
• CPC Class Codes: G01R 31/367 Software therefor, e.g. for battery testing using modelling or look-up tables
• CPC Class Codes: G01R 31/382 Arrangements for monitoring battery or accumulator variables, e.g. SoC
• CPC Class Codes: G01R 31/389 Measuring internal impedance, internal conductance or related variables
• CPC Class Codes: G07C 5/008 communicating information to a remotely located station transmission systems for measured values G08C
• CPC Class Codes: Y02T 10/62 Hybrid vehicles
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 10/7072 : Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors

Abstract

In an embodiment, a system includes a battery management unit (BMU) coupled to a battery pack of an xEV. Further, the BMU is configured to determine an energy remaining value for the battery pack based, at least in part, on a minimum cell temperature and a minimum cell state of charge percentage (SOC %) determined by the BMU for the battery pack.

Claims

1. A system, comprising:

a battery management unit (BMU) coupled to a battery pack of an xEV, wherein the BMU is configured to determine an energy remaining value for the battery pack based, at least in part, on a minimum cell temperature and a minimum cell state of charge percentage (SOC %) determined by the BMU for the battery pack.

2. The system of claim 1, wherein the BMU is configured to provide the determined energy remaining value to a vehicle control unit (VCU) of the xEV, and wherein the VCU is configured to determine a range remaining for the xEV in distance, time, or both, based, at least in part, on the energy remaining value provided by the BMU.

3. The system of claim 2, wherein the VCU is configured to instruct an instrument cluster to display the range remaining for the xEV in distance, time, or both.

4. The system of claim 1, wherein the BMU is configured to use one or more look-up tables to determine the energy remaining value.

5. The system of claim 4, wherein the one or more look-up tables comprise at least one table relating the minimum cell SOC % to an average cell voltage of the battery pack.

6. The system of claim 4, wherein the one or more look-up tables comprise at least one table relating both the minimum cell SOC % and the minimum cell temperature to a discharge resistance of the battery pack.

7. The system of claim 4, wherein the one or more look-up tables comprise at least one table relating both the minimum cell SOC % and the minimum cell temperature to a beginning of life (BOL) energy remaining value for the battery pack.

8. The system of claim 7, wherein the BMU is configured to determine the energy remaining value for the battery pack based, at least in part, on the BOL energy remaining value and a weighting factor.

9. The system of claim 8, wherein the weighting factor is based, at least in part, on a cell resistance aging factor that is based on a calendar or cycle life of the battery pack or based on a real-time aging determination algorithm.

10. The system of claim 1, wherein the BMU is configured to determine the energy remaining based, at least in part, on an average cell voltage, a discharge resistance, a discharge voltage, and a remaining SOC % of the battery pack.

11. The system of claim 1, wherein the BMU is configured to determine the energy remaining based, at least in part, on a cell capacity, a number of cells, a discharge current, and a lower limit SOC % of the battery pack.

12. The system of claim 1, wherein the BMU is configured to determine the energy remaining based, at least in part, on a cell resistance aging factor that is based on a calendar or cycle life of the battery pack or based on a real time aging determination algorithm.

13. The system of claim 1, wherein the BMU determines an energy remaining value based, at least in part, on a driving profile weighting factor that is based on a driving style typical for the xEV to experience.

14. A system, comprising:

a battery pack for an xEV, comprising;

a plurality of electrochemical cells; and

a battery management unit (BMU) configured to determine an energy remaining in the plurality of electrochemical cells based, at least in part, on a minimum measured cell temperature and a minimum measured cell state of charge percentage (SOC %) of the plurality of electrochemical cells.

15. The system of claim 14, wherein the BMU is configured to determine the energy remaining in the plurality of electrochemical cells based, at least in part, on a cell resistance aging factor that is based on a calendar or cycle life of the plurality of electrochemical cells or based on a real time aging determination algorithm.

16. The system of claim 14, wherein the BMU is configured to determine or receive a driving profile weighting factor from a vehicle control unit (VCU), and configured to use the driving profile weighting factor to determine the energy remaining in the plurality of electrochemical cells.

17. The system of claim 16, wherein the BMU is configured to communicate to the VCU a value corresponding to the energy remaining in the electrochemical cells.

18. The system of claim 17, wherein the VCU is configured to receive, from the BMU, the value corresponding to the energy remaining in the electrochemical cells, and configured to use the value to determine a time, a distance, or a combination thereof, that the xEV may travel by consuming the remaining energy in the plurality of electrochemical cells.

19. The system of claim 18, wherein the VCU is configured to instruct an instrument cluster to display the time, the distance, or a combination thereof, that the xEV may travel by consuming the remaining energy in the plurality of electrochemical cells.

20. An xEV, comprising:

a battery configured to supply electrical power to propel the xEV;

a battery management unit (BMU) configured to monitor and control the battery pack; and

a vehicle control unit (VCU) communicatively coupled to the BMU, wherein the BMU, the VCU, or a combination thereof, are configured to determine an energy remaining value for the battery pack based, at least in part, on a measured cell temperature and a measured minimum state of charge percentage (SOC %) of the battery pack.

21. The system of claim 20, wherein the VCU is configured to determine a remaining range of the xEV based, at least in part, on the determined energy remaining value.

22. The system of claim 21, wherein the VCU is configured to instruct an instrument cluster to display the determined remaining range of the xEV.

23. The system of claim 20, comprising an internal combustion engine, a generator, and a fuel tank storing fuel, wherein the internal combustion engine is configured to combust the fuel from the fuel tank to power the generator, and wherein the generator is configured supply electrical power to the battery pack.

24. The system of claim 23, wherein the VCU is configured to determine an amount of energy that the fuel in the fuel tank of the xEV will provide to the battery pack when the fuel is combusted by the internal combustion engine.

25. The system of claim 24, wherein the VCU is configured to determine a remaining range of the xEV based, at least in part, on the determined energy remaining value for the battery pack and the determined amount of energy that the fuel from the fuel tank of the xEV will provide.

26. The system of claim 25, wherein the VCU is configured to instruct an instrument cluster to display the determined remaining range of the xEV.

27. A method, comprising:

monitoring a plurality of parameters of a battery pack of an xEV, wherein the plurality of parameters comprises a minimum cell temperature and a minimum cell state of charge percentage (SOC %) of the battery pack;

determining an energy remaining value for the battery pack of the xEV based, at least in part, on a SOC % remaining, a number of cells, a cell capacity, and a discharge voltage for the battery pack;

determining a range for the xEV based, at least in part, on the determined energy remaining value; and

instructing an instrument cluster of the xEV to display the range of the xEV.

28. The method of claim 27, comprising determining the SOC % remaining for the battery pack based, at least in part, on the minimum cell SOC %, a lower limit SOC % of the battery pack, and a driving profile weighting factor.

29. The method of claim 28, wherein the lower limit SOC % comprises a minimal cell SOC % that the battery pack should maintain.

30. The method of claim 28, wherein the driving profile weighting factor is based, at least in part, on a driving style experienced by the xEV.

31. The method of claim 27, comprising determining the discharge voltage for the battery pack based, at least in part, on an average cell voltage, a cell resistance aging factor, a discharge resistance, and a discharge current of the battery pack.

32. The method of claim 31, comprising determining the average cell voltage for the battery pack based, at least in part, on the minimum cell SOC % of the battery pack.

33. The method of claim 31, comprising determining the discharge resistance for the battery pack based, at least in part, on the minimum cell SOC % and the minimum cell temperature of the battery pack.

34. The method of claim 33, wherein determining the discharge resistance for the battery pack comprises using a look-up table and the minimum cell SOC % and the minimum cell temperature of the battery pack.