Dual-battery system

• US 6,275,001 B1
• Filed: 09/16/1999
• Issued: 08/14/2001
• Est. Priority Date: 09/17/1998
• Status: Expired due to Term

• Current Assignee: Volkswagen AG
• Original Assignee: Volkswagen AG
• Inventors: Dierker, Uwe
• Primary Examiner(s): Tso, Edward H.
• Application Number:
  US09/397,209
• Time in Patent Office: 698 Days
• Field of Search: 320/103, 320/104, 320/116, 320/117, 320/135, 320/136, 307/10.1, 307/10.7, 307/46, 307/66, 307/151
• US Class Current: 320/103
• CPC Class Codes: B60R 16/03 for supply of electrical power to vehicle subsystems or for circuit arrangements for charging batteries H02J7/00
• CPC Class Codes: F02N 11/0866 comprising several power sources, e.g. battery and capacitor or two batteries
• CPC Class Codes: F02N 11/087 Details of the switching means in starting circuits, e.g. relays or electronic switches
• CPC Class Codes: F02N 2200/0805 Detection of vehicle emergency state, e.g. from ABS, ESP, external sensors
• CPC Class Codes: H02J 2310/46 for ICE-powered road vehicles
• CPC Class Codes: H02J 7/1423 with multiple batteries
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries

Abstract

The subject invention relates to a dual-battery system, that includes a generator (1), a starter (3), a starter battery (2), a starter battery switch, a vehicle electrical system battery (5), and a control device (7), in which the starter battery (2), along with the starter battery switch that is connected in series, is connected in parallel with the generator (1), starter (3), and vehicle electrical system battery (5), and the starter battery switch can be activated by the control device (7), the starter battery switch being configured as a power MOSFET (6) whose gate is connected to the control device (7).

Claims

1. A dual-battery system, comprising a generator, a starter, a starter battery, a starter battery switch, a vehicle electrical system battery, and a control device, in which the starter battery is connected in series with the starter battery switch, and the starter battery and starter battery switch are connected in parallel with the generator, starter, and vehicle electrical system battery, and the starter battery switch can be activated by the control device, and wherein the starter battery switch is configured as a power MOSFET having a gate connected to the control device.

3. The dual-battery system as defined in claim 1 or 2, wherein the MOSFET includes an internal overcurrent protector.

4. The dual-battery system as defined in claim 1 or 2, further including at least one of a precrash sensor or crash sensor associated with the control device.

5. The dual-battery system as defined in claim 3, further including at least one of a precrash sensor or crash sensor associated with the control device.

6. The dual-battery system as defined in claim 1, 2 or 5, further comprising a second MOSFET connected in series with the vehicle electrical system battery.

7. The dual-battery system as defined in claim 3, further comprising a second MOSFET connected in series with the vehicle electrical system battery.

8. The dual-battery system as defined in claim 4, further comprising a second MOSFET connected in series with the vehicle electrical system battery.

2. A dual-battery system comprising a generator, a starter, a starter battery, a starter battery switch, a vehicle electrical system battery, and a control device, in which the starter battery along with the starter battery switch that is connected in series, is connected in parallel with the generator, starter, and vehicle electrical system battery, and the starter battery switch can be activated by the control device, and wherein the starter battery switch is configured as a power MOSFET having a gate connected to the control device;

wherein the power MOSFET includes an internal current measurement system that is connected to the control device.

9. A method for activating a dual-battery system including a generator, a starter, a starter battery, a starter battery switch, a vehicle electrical system battery, and a control device, in which the starter battery, along with the starter battery switch that is connected in series, is connected in parallel with the generator, starter, and vehicle electrical system battery, and the starter battery switch can be activated by the control device, and the starter battery switch is configured as a power MOSFET having a gate connected to the control device, wherein the control device performs the following steps:

a) sensing the initiation of a starting operation upon actuation of the starter;

b) generating a gate voltage that makes the MOSFET conductive;

c) continuously sensing the drain current of the MOSFET; and

d) shutting off the gate voltage if a drain current profile indicates termination of the starting operation.

10. The method for activating a dual-battery system as defined in claim 9, wherein the system further includes at least one of a precrash or crash sensor, and wherein the control device inhibits the MOSFETs when a collision is sensed by the precrash sensor or the crash sensor.