Multi-battery system for increasing the electric range

• US 10,179,519 B2
• Filed: 10/18/2014
• Issued: 01/15/2019
• Est. Priority Date: 04/24/2014
• Status: Active Grant

• Current Assignee: Audi AG (Volkswagen AG)
• Original Assignee: Audi AG (Volkswagen AG)
• Inventors: Schmidt, Jorg
• Primary Examiner(s): Grant, Robert
• Assistant Examiner(s): TRISCHLER, JOHN T
• Application Number:
  US15/305,022
• Publication Number:
  US 20170182910A1
• Time in Patent Office: 1,550 Days
• Field of Search: 320104
• CPC Class Codes: B60L 3/0046 relating to electric energy storage systems, e.g. batteries or capacitors
• 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 58/12 responding to state of charge [SoC]
• CPC Class Codes: B60L 58/18 of two or more battery modules
• CPC Class Codes: B60L 58/20 having different nominal voltages
• CPC Class Codes: B60L 58/21 having the same nominal voltage
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries

Abstract

A motor vehicle includes an high-voltage power system, a multi-battery system including energy stores for supplying power to an electric drive motor, and switching units connecting the energy stores to the power system. A control device detects a state of charge of each energy store and to selectively connect and/or disconnect the energy stores as a function of their state of charge during travel to and from the power system. The switching units include each contactors to disconnect the energy stores on a plus side and on a minus side from the power system, with only either the positive side or negative side of each energy store including a contactor configured to switch when a load is greater than a minimum load, whereas the other one of the positive and negative sides includes a contactor that is adequate only for a load demand which is less than the minimum load.

Claims

1. A motor vehicle, comprising:

an electric drive motor;

an on-board high-voltage power system having a plus side and a minus side;

a multi-battery system comprising a plurality of mutually galvanically insulated energy stores for supplying a driving current to the electric drive motor, wherein each of the energy stores has a positive and negative polarity;

a plurality of contactors associated with each of the energy stores, with a first contactor connecting the positive polarity of that energy store to the plus side of the on-board high-voltage power system and a second contactor connecting the negative polarity of that the enemy store to the minus side of the on-board high-voltage power system; and

a control device configured to operate the first and second contactors as a function of a detected state of charge of each energy store by selectively connecting and/or disconnecting the energy stores from the on-board high-voltage power system while supplying the driving current to the electric drive motor,

wherein for each of the energy stores one of the first and second contactors is constructed to switch a driving current that is greater than a minimum current, whereas the other one of the first and second contactors is constructed to switch a driving current that is smaller than or at most equal to the minimum current.

2. The motor vehicle of claim 1, wherein the drive motor includes an inverter to form the control device.

3. The motor vehicle of claim 1, wherein the control device is configured to detect during travel an operating state, in which a load demand is smaller than a predefined threshold value.

4. The motor vehicle of claim 1, further comprising a common housing configured to accommodate the plurality of the energy stores.

5. The motor vehicle of claim 1, wherein the plurality of the energy stores are dispersed in the motor vehicle.

6. The motor vehicle of claim 1, wherein the plurality of the energy stores have different power data.

7. The motor vehicle of claim 1, wherein only one of the plurality of energy stores is connected to the on-board high-voltage power system at one time.

8. A method of operating a motor vehicle, comprising:

supplying a driving current to an electric motor of the motor vehicle from an on-board high-voltage power system having a plus side and a minus side;

detecting with a control device a state of charge of a plurality of mutually galvanically insulated energy stores of a multi-battery system;

while under load when the driving current flows,

selectively connecting, depending on the state of charge, a positive polarity of an energy store to the plus side of the on-board high-voltage power system by closing a first contactor and a negative polarity of the enemy store to the minus side of the on-board high-voltage power system by closing a second contactor, and

disconnecting respective positive and negative polarities of another energy store from the respective plus and minus sides of the on-board high-voltage power system by opening the respective first and second contactors connecting the other energy store to the on-board high-voltage power system, wherein one of the first and second contactors is constructed to switch a driving current that is greater than a minimum current, whereas the other one of the first and second contactors is constructed to switch a driving current that is smaller than or at most equal to the minimum current.

9. The method of claim 8, wherein only one of the plurality of energy stores is connected to the on-board high-voltage power system at one time.