System and method for adjusting battery pack state of charge limits

• US 9,340,120 B2
• Filed: 10/11/2013
• Issued: 05/17/2016
• Est. Priority Date: 10/11/2013
• Status: Active Grant

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Chang, Xiaoguang, He, Chuan, Wang, Xu
• Primary Examiner(s): CAMBY, RICHARD M
• Application Number:
  US14/052,645
• Publication Number:
  US 20150105947A1
• Time in Patent Office: 949 Days
• Field of Search: 701/22
• US Class Current: 1/1
• CPC Class Codes: B60L 2240/26 Vehicle weight
• CPC Class Codes: B60L 2240/545 Temperature
• CPC Class Codes: B60L 58/13 Maintaining the SoC within a determined range
• CPC Class Codes: B60L 58/15 Preventing overcharging
• CPC Class Codes: B60L 58/21 having the same nominal voltage
• CPC Class Codes: H02J 7/00 Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
• CPC Class Codes: H02J 7/00302 Overcharge protection
• CPC Class Codes: H02J 7/00306 Overdischarge protection
• 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
• CPC Class Codes: Y10S 903/903 having energy storing means, e.g. battery, capacitor

Abstract

Systems and methods for operating a battery pack supplying power to propel a vehicle are disclosed. One example method comprises, adjusting a battery pack state of charge window in response to vehicle mass. Adjusting the battery pack state of charge window in response to vehicle mass may allow the battery pack to provide an increased amount of energy to a motor so that the motor may provide torque to a driveline for a longer period of time and/or absorb more vehicle generator produced power during vehicle operations.

Claims

1. A system for operating a battery pack of a vehicle, comprising:

a battery pack including a plurality of battery cells; and

a controller including non-transitory instructions for adjusting battery pack state of charge operating thresholds in response to vehicle mass, where the battery pack state of charge operating thresholds include an adjustable battery state of charge maximum level threshold and an adjustable battery state of charge minimum level threshold.

2. The system of claim 1, where vehicle mass includes vehicle cargo and passengers, and where the adjustable battery state of charge maximum level threshold is increased in response to an increase in the vehicle mass and the adjustable battery state of charge minimum level threshold is decreased in response to the increase in the vehicle mass.

3. The system of claim 1, where vehicle mass includes mass of a trailer mechanically coupled to the vehicle, and further comprising providing zero battery pack charging power when a battery pack state of charge is at the adjustable battery state of charge maximum level threshold.

4. The system of claim 1, where adjusting battery pack state of charge operating thresholds includes decreasing the adjustable battery state of charge maximum level threshold in response to a decrease in the vehicle mass and increasing the adjustable battery state of charge minimum level threshold in response to the decrease in the vehicle mass.

5. The system of claim 1, further comprising adjusting battery pack charging power in response to the vehicle mass.

6. The system of claim 1, further comprising increasing a battery pack charging power at a particular battery state of charge level in response to an increase in vehicle mass.

7. The system of claim 1, further comprising increasing a battery pack discharging power at a particular battery state of charge level in response to an increase in vehicle mass.

8. A method for operating a battery pack, comprising:

providing an adjustable battery state of charge maximum level threshold for battery pack charging;

adjusting the adjustable battery state of charge maximum level threshold for battery pack charging in response to vehicle mass; and

providing zero battery pack charging power when a battery state of charge is at the adjustable battery state of charge maximum level threshold.

9. The method of claim 8, further comprising adjusting the adjustable battery state of charge maximum level threshold in response to humidity, and where the adjustable battery state of charge maximum level threshold is less than or equal to a value equal to battery ampere hour capacity.

10. The method of claim 8, where the vehicle mass includes mass of a trailer mechanically coupled to a vehicle, and further comprising an adjustable battery state of charge minimum level threshold adjusted in response to vehicle mass, and providing zero battery pack discharging power when the battery state of charge is at the adjustable battery state of charge minimum level threshold.

11. The method of claim 8, further comprising adjusting an adjustable state of battery charge high level threshold where battery charging power is reduced before battery charging power is zero at the adjustable battery state of charge maximum level threshold.

12. The method of claim 8, where adjusting the adjustable battery state of charge maximum level threshold includes decreasing the adjustable battery state of charge maximum level threshold in response to a decrease in vehicle mass.

13. The method of claim 8, further comprising reducing the adjustable battery state of charge maximum level threshold in response to no change in vehicle mass after a predetermined duration.