Thermal Management Controls for a Vehicle Having a Rechargeable Energy Storage System

• US 20120082871A1
• Filed: 09/30/2010
• Published: 04/05/2012
• Est. Priority Date: 09/30/2010
• 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: Martinchick, Matthew J., Ziehr, Lawrence P., Buford, Keith D., Lombardo, Paul S., Nolte, Jason J., Simonini, Matthew, Shen, Stephen L., Williams, Jonathan K.
• Granted Patent: US 8,932,743 B2
• Time in Patent Office: Days
• US Class Current: 429/50
• CPC Class Codes: B60L 1/04 fed by the power supply line
• CPC Class Codes: B60L 53/00 Methods of charging batteries, specially adapted for electric vehicles; Charging stations or on-board charging equipment therefor; Exchange of energy storage elements in electric vehicles
• CPC Class Codes: B60L 58/24 for controlling the temperature of batteries
• CPC Class Codes: H01M 10/625 Vehicles
• CPC Class Codes: H01M 10/66 Heat-exchange relationships between the cells and other systems, e.g. central heating systems or fuel cells
• CPC Class Codes: H01M 2220/20 Batteries in motive systems, e.g. vehicle, ship, plane
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• 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: Y02T 90/14 Plug-in electric vehicles

Abstract

A method of operating a RESS thermal system in a vehicle having a coolant loop for directing a coolant through a RESS and a refrigerant loop configured to selectively cool the coolant flowing through a chiller in the coolant loop, including: determining a current target temperature range for the RESS based on a current vehicle operating mode and ambient temperature; determining a temperature of the RESS; determining if the temperature of the RESS needs to increase or decrease to be within the current target temperature range; if the determination is made that the temperature of the RESS needs to increase, determining if an active heating or a passive heating of the coolant will be employed, the active heating using a greater amount of energy over a shorter time period than the passive heating; and activating the determined active heating or passive heating of the coolant.

Claims

1. A method of operating a RESS thermal system in a vehicle having a coolant loop for directing a coolant through a RESS and a refrigerant loop configured to selectively cool the coolant flowing through a chiller in the coolant loop, the method comprising the steps of:

(a) determining a current target temperature range for the RESS based on at least a current vehicle operating mode and ambient temperature, the target temperature range being variable based on the current vehicle operating mode and ambient temperature;

(b) determining a temperature of the RESS;

(c) determining if the temperature of the RESS needs to increase or decrease to be within the current target temperature range;

(d) if the determination is made that the temperature of the RESS needs to increase, determining if an active heating or a passive heating of the coolant will be employed, the active heating using a greater amount of energy over a shorter time period than the passive heating; and

(e) activating the determined active heating or passive heating of the coolant from step (d).

2. The method of claim 1 further comprising:

(f) if the determination is made that the temperature of the RESS needs to decrease, determining if an active cooling or a passive cooling of the coolant will be employed, the active cooling using a greater amount of energy over a shorter time period than the passive heating; and

(g) activating the determined active cooling or passive cooling of the coolant from step (f).

3. The method of claim 2 wherein steps (f) and (g) are further defined by the active cooling including operating a refrigerant compressor and directing cooled refrigerant through the chiller through which the coolant is directed, and the passive cooling includes directing the coolant through a RESS radiator and directing airflow through the RESS radiator to absorb heat from the coolant.

4. The method of claim 2 wherein, if the passive cooling is activated in step (g), monitoring the rate of change of the coolant temperature and switching from the passive cooling to the active cooling if the rate of change of the coolant is below a predetermined threshold.

5. The method of claim 1 wherein step (d) and (e) are further defined by the active heating including operating an electric coolant heater to heat the coolant just prior to flowing through the RESS, and the passive heating includes directing the coolant through a RESS radiator and directing airflow through the RESS radiator to add heat to the coolant.

6. The method of claim 1 wherein step (a) is further defined by adjusting the current temperature range based on the time of day at which the target temperature range is being determined.

7. The method of claim 1 wherein step (a) is further defined by the current vehicle operating mode comprising one of a delayed charging mode, a vehicle charging mode and a charge complete mode, and wherein the current target temperature range is different for each of the modes.

8. The method of claim 1 wherein step (a) is further defined by the current vehicle operating mode comprising one of a charge depletion driving mode and a charge sustaining driving mode, and wherein the current target temperature range is different for each of the modes.

9. The method of claim 1 wherein, if the passive heating is activated in step (e), monitoring the rate of change of the coolant temperature and switching from the passive heating to the active heating if the rate of change of the coolant is below a predetermined threshold.

10. The method of claim 1 further comprising:

(f) powering down the vehicle;

(g) determining the RESS temperature at power down;

(h) determining an ambient temperature at power down;

(i) determining a time period to wait after power down to wakeup the RESS thermal system and provide RESS battery heating or cooling, if needed, based on at least the determined RESS temperature and ambient temperature at power down; and

(j) waking up the RESS thermal system after the predetermined time period.

11. The method of claim 10 further comprising (k) determining a time of day at power down;

and wherein step (i) is further defined by determining the time period to wait after power down based on at least the determined RESS temperature, ambient temperature and time of day at power down.

12. The method of claim 10 further comprising:

(k) determining a RESS temperature and an ambient temperature at an end of the wake up in step (j); and

(l) determining a time period to wait after the end of the wake up to again wake up the RESS thermal system and provide RESS battery heating or cooling, if needed.

13. A method of operating a RESS thermal system in a vehicle having a coolant loop for directing a coolant through a RESS and a refrigerant loop configured to selectively cool the coolant flowing through a chiller in the coolant loop, the method comprising the steps of:

(a) powering down the vehicle;

(b) determining the RESS temperature at power down;

(c) determining an ambient temperature at power down;

(d) determining a time period to wait after power down to wakeup the RESS thermal system and provide RESS battery heating or cooling, if needed, based on at least the determined RESS temperature and ambient temperature at power down;

(e) waking up the RESS thermal system after the predetermined time period; and

(f) providing RESS heating or cooling, as needed, after waking up the RESS thermal system.

14. The method of claim 13 further comprising (g) determining a time of day at power down;

and wherein step (d) is further defined by determining the time period to wait after power down based on at least the determined RESS temperature, ambient temperature and time of day at power down.

15. The method of claim 13 further comprising:

(g) determining a RESS temperature and an ambient temperature at an end of the wake up in step (f); and

(h) determining a time period to wait after the end of the wake up to again wake up the RESS thermal system and provide RESS battery heating or cooling, if needed.

16. The method of claim 13 further comprising:

(g) determining a current target temperature range for the RESS based on at least a current vehicle operating mode and ambient temperature, the target temperature range being variable based on the current vehicle operating mode and ambient temperature;

(h) determining a temperature of the RESS;

(i) determining if the temperature of the RESS needs to increase or decrease to be within the current target temperature range;

(j) if the determination is made that the temperature of the RESS needs to decrease, determining if an active cooling or a passive cooling of the coolant will be employed, the active cooling using a greater amount of energy over a shorter time period than the passive cooling; and

(k) activating the determined active cooling or passive cooling of the coolant from step (j).

17. The method of claim 16 wherein steps (j) and (k) are further defined by the active cooling including operating a refrigerant compressor and directing cooled refrigerant through the chiller through which the coolant is directed, and the passive cooling includes directing the coolant through a RESS radiator and directing airflow through the RESS radiator to absorb heat from the coolant.

18. The method of claim 17 wherein, if the passive cooling is activated in step (k), monitoring the rate of change of the coolant temperature and switching from the passive cooling to the active cooling if the rate of change of the coolant is below a predetermined threshold.

19. The method of claim 16 wherein step (g) is further defined by adjusting the current temperature range based on the time of day at which the target temperature range is being determined.

20. The method of claim 16 wherein step (g) is further defined by the current vehicle operating mode comprising one of a delayed charging mode, a vehicle charging mode and a charge complete mode, and wherein the current target temperature range is different for each of the modes.