BATTERY CHARGING CONTROL METHODS AND APPARATUS

• US 20100270980A1
• Filed: 04/24/2009
• Published: 10/28/2010
• Est. Priority Date: 04/24/2009
• Status: Active Grant

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations Incorporated (Motors Liquidation Co. GUC Trust)
• Inventors: GROSHEK, PAUL G., MARSH, RICHARD A., JOHNSON, CAROL L., NEWHOUSE, VERNON L.
• Granted Patent: US 8,253,387 B2
• Time in Patent Office: Days
• US Class Current: 320/152
• CPC Class Codes: B60L 2200/26 Rail vehicles
• CPC Class Codes: B60L 58/20 having different nominal voltages
• CPC Class Codes: H02J 7/007192 in response to temperature
• CPC Class Codes: H02J 7/007194 of the battery
• CPC Class Codes: H02J 7/04 Regulation of charging current or voltage
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries

Abstract

Embodiments include methods for charging a battery of an electrical system. The electrical system includes the battery, a battery charger, and a controller. The battery charger is adapted to produce an output power in response to a control signal from the controller. The controller is adapted to control a battery charging process by determining a temperature of the battery pack, determining a voltage setpoint for the battery charger based on the temperature, and providing the control signal to the battery charger. According to an embodiment, when the temperature of the battery exceeds a first temperature value, the battery charging process is temporarily suspended prior to satisfying a charging termination criterion. Determining the temperature of the battery is repeated, and when the temperature of the battery is less than a second temperature value, the battery charging process is resumed.

Claims

1. A method for charging a battery of an electrical system that includes the battery, a battery charger, and a controller, the method comprising the steps of:

determining a temperature of the battery;

determining, based on the temperature, a voltage setpoint for the battery charger; and

controlling the battery charger to produce an output power that results in increasing an output voltage of the battery toward the voltage setpoint.

2. The method of claim 1, wherein determining the voltage setpoint comprises:

calculating the voltage setpoint as a function of the temperature.

3. The method of claim 1, wherein determining the voltage setpoint comprises:

determining the voltage setpoint from a table of temperature/setpoint values.

4. The method of claim 1, wherein determining the voltage setpoint comprises:

determining an allowable state of charge of the battery based on the temperature, wherein the allowable state of charge is less than a maximum state of charge of the battery; and

determining the voltage setpoint based on the allowable state of charge.

5. The method of claim 4, wherein determining the voltage setpoint comprises:

calculating the voltage setpoint as a function of the allowable state of charge.

6. The method of claim 4, wherein determining the voltage setpoint comprises:

determining the voltage setpoint from a table of state of charge/setpoint values.

7. The method of claim 1, further comprising:

determining whether a charging termination criteria has been satisfied; and

when the charging termination criteria has been satisfied, terminating the process of charging the battery.

8. The method of claim 1, wherein the charging termination criteria is a criteria selected from a group that includes the battery having reached a maximum state of charge and a battery voltage having reached a maximum battery voltage.

9. A method for charging a battery of an electrical system that includes the battery, a battery charger, and a controller, the method comprising the steps of:

initiating a charging process to charge the battery;

determining a temperature of the battery;

when the temperature of the battery exceeds a first temperature value, temporarily suspending the battery charging process prior to satisfying a charging termination criterion;

repeating determining the temperature of the battery; and

when the temperature of the battery is less than a second temperature value, resuming the battery charging process.

10. The method of claim 9, wherein temporarily suspending the battery charging process comprises:

determining, based on the temperature, a voltage setpoint for the battery charger, wherein the voltage setpoint is less than a maximum battery voltage; and

controlling the battery charger to produce an output power that results in increasing an output voltage of the battery toward the voltage setpoint.

11. The method of claim 10, wherein determining the voltage setpoint comprises:

determining an allowable state of charge of the battery based on the temperature, wherein the allowable state of charge is less than a maximum state of charge of the battery; and

determining the voltage setpoint based on the allowable state of charge.

12. The method of claim 9, wherein resuming the battery charging process comprises:

determining, based on the temperature, a voltage setpoint for the battery charger, wherein the voltage setpoint is less than a maximum battery voltage; and

controlling the battery charger to produce an output power that results in increasing an output voltage of the battery toward the voltage setpoint.

13. The method of claim 12, wherein determining the voltage setpoint comprises:

determining an allowable state of charge of the battery based on the temperature, wherein the allowable state of charge is less than a maximum state of charge of the battery; and

determining the voltage setpoint based on the allowable state of charge.

14. An electrical system comprising:

a high voltage (HV) energy storage system having a battery pack that is adapted to store electrical energy;

a battery charger adapted to produce an output voltage in response to a control signal that indicates a voltage setpoint for the output voltage; and

a controller adapted to control a battery charging process by determining a temperature of the battery pack, determining a voltage setpoint for the battery charger based on the temperature, and providing the control signal to the battery charger.

15. The electrical system of claim 14, further comprising:

an alternating current (AC) power interface adapted to provide a status signal to the controller, which indicates whether or not the AC power interface is electrically coupled with an external AC power source,

wherein the controller is adapted to initiate the battery charging process in response to receiving the status signal.

16. The electrical system of claim 14, wherein the HV energy storage system further comprises:

one or more temperature sensors adapted to provide temperature signals to the controller, wherein the controller uses the temperature signals to determine the temperature of the battery pack; and

a voltage sensor adapted to provide voltage signals to the controller, which indicate a current voltage across terminals of the battery pack.

17. The electrical system of claim 14, wherein the battery pack is adapted to produce a maximum output voltage across its terminals of 300 volts or more.

18. The electrical system of claim 14, wherein the battery pack is adapted to produce a maximum output voltage across its terminals of 60 volts or more.

19. The electrical system of claim 14, wherein the controller is further adapted to temporarily suspend the battery charging process prior to satisfying a charging termination criteria, when the temperature of the battery pack exceeds a first temperature value, and to resume the battery charging process when the temperature of the battery pack is less than a second temperature value.

20. The electrical system of claim 14, wherein the controller is further adapted to temporarily suspend the battery charging process by determining, based on the temperature, the voltage setpoint as a voltage setpoint that is less than a maximum battery voltage.