INTERNALLY REFERENCED SCALABLE AUTO DISCHARGE METHOD FOR HYBRID ELECTRIC VEHICLES

• US 20140015491A1
• Filed: 07/10/2012
• Published: 01/16/2014
• Est. Priority Date: 07/10/2012
• Status: Abandoned Application

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations LLC (General Motors Company)
• Inventors: Namou, Andrew J., Mackintosh, Todd F.
• Application Number:
  US13/545,770
• Publication Number:
  US 20140015491A1
• Time in Patent Office: Days
• US Class Current: 320/135
• CPC Class Codes: B60L 2240/547 Voltage
• CPC Class Codes: B60L 2240/549 Current
• CPC Class Codes: B60L 3/0007 Measures or means for preventing or attenuating collisions
• CPC Class Codes: B60L 3/0046 relating to electric energy storage systems, e.g. batteries or capacitors
• CPC Class Codes: B60L 3/0069 relating to the isolation, e.g. ground fault or leak current
• CPC Class Codes: B60L 3/04 Cutting off the power supply under fault conditions protective devices and circuit arrangements in general H01H; H02H
• CPC Class Codes: B60L 58/18 of two or more battery modules
• CPC Class Codes: H01M 10/44 Methods for charging or discharging circuits for charging H02J7/00
• CPC Class Codes: H01M 2220/20 Batteries in motive systems, e.g. vehicle, ship, plane
• CPC Class Codes: H02J 7/0029 with safety or protection devices or circuits
• CPC Class Codes: H02J 7/007182 in response to battery voltage
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries

Abstract

A circuit for discharging a battery including a voltage divider network having a plurality of resistors and being electrically coupled in parallel with the battery, where the voltage divider network divides a voltage potential of the battery and where a voltage potential across one of the resistors in the voltage divider network provides a reference voltage. The circuit also includes a load electrically coupled in parallel with the battery and the voltage divider network and a switch electrically coupled in series with the load and being controlled by the reference voltage. A current flow through the load generated by the battery discharges the battery which causes the reference voltage to decrease until the reference voltage falls to a predetermined voltage that causes the switch to open so that the battery is discharged to the predetermined voltage. The switch can be a soft-switch or a hard-switch.

Claims

1. A discharge circuit for discharging a battery, said circuit comprising:

a voltage divider network including a plurality of resistors and being electrically coupled in parallel with the battery, said voltage divider network dividing a voltage potential of the battery where a voltage potential across one of the resistors in the voltage divider network provides a reference voltage;

a load electrically coupled in parallel with the battery and the voltage divider network; and

a control switch electrically coupled in series with the load and being controlled by the reference voltage, wherein a current flow through the load generated by the battery discharges the battery which causes the reference voltage to decrease until the reference voltage falls to a predetermined voltage that causes the control switch to open so that the battery is discharged to the predetermined voltage.

2. The circuit according to claim 1 wherein the control switch is a semiconductor switch having a gate terminal and wherein the reference voltage is electrically coupled to the gate terminal.

3. The circuit according to claim 1 wherein the control switch is a relay-type switch including a coil where the reference voltage energizes the coil.

4. The circuit according to claim 3 further comprising a starting power source and a push button electrically coupled to the control switch where the control switch is closed in response to closing the push button that provides power from the power source.

5. The circuit according to claim 1 wherein the voltage source is a variable voltage source so that the reference voltage can be changed.

6. The circuit according to claim 1 wherein the voltage source and the load are part of a portable unit that can be selectively coupled to the battery.

7. The circuit according to claim 1 further comprising a start switch, said start switch being closed to start the discharging of the battery.

8. The circuit according to claim 1 wherein the load is one or more resistors.

9. The circuit according to claim 1 wherein the battery is a high voltage battery having a voltage of 400 volts or more.

10. The circuit according to claim 1 where the battery is a vehicle battery.

11. A discharge circuit for discharging a vehicle battery, said circuit comprising:

a voltage divider network including a plurality of resistors and being electrically coupled in parallel with the battery, said voltage divider network dividing a voltage potential of the battery where a voltage potential across one of the resistors in the voltage divider network provides a reference voltage;

a load electrically coupled in parallel with the battery and the voltage divider network; and

a semiconductor switch electrically coupled in series with the load and being controlled by the reference voltage, said semiconductor switch having a gate terminal where the reference voltage is electrically coupled to the gate terminal, wherein a current flow through the load generated by the battery discharges the battery which causes the reference voltage to decrease until the reference voltage falls to a predetermined voltage that causes the switch to open so that the battery is discharged to the predetermined voltage.

12. The circuit according to claim 11 wherein the voltage source is a variable voltage source so that the reference voltage can be changed.

13. The circuit according to claim 11 wherein the voltage source and the load are part of a portable unit that can be selectively coupled to the battery.

14. The circuit according to claim 11 further comprising a start switch, said start switch being closed to start the discharging of the battery.

15. The circuit according to claim 11 wherein the load is one or more resistors.

16. A discharge circuit for discharging a vehicle battery, said circuit comprising:

a voltage divider network including a plurality of resistors and being electrically coupled in parallel with the battery, said voltage divider network dividing a voltage potential of the battery where a voltage potential across one of the resistors in the voltage divider network provides a reference voltage;

a load electrically coupled in parallel with the battery and the voltage divider network; and

a relay switch electrically coupled in series with the load and being controlled by the reference voltage, said relay switch including a coil where the reference voltage energizes the coil, wherein a current flow through the load generated by the battery discharges the battery which causes the reference voltage to decrease until the reference voltage falls to a predetermined voltage that causes the switch to open so that the battery is discharged to the predetermined voltage.

17. The circuit according to claim 16 further comprising a starting power source and a push button electrically coupled to the control switch where the control switch is closed in response to closing the push button that provides power from the power source.

18. The circuit according to claim 16 wherein the voltage source is a variable voltage source so that the reference voltage can be changed.

19. The circuit according to claim 16 wherein the voltage source and the load are part of a portable unit that can be selectively coupled to the battery.