Battery for a vehicle and method of operating such a battery

• US 9,252,418 B2
• Filed: 02/15/2012
• Issued: 02/02/2016
• Est. Priority Date: 03/09/2011
• Status: Active Grant

• Current Assignee: Audi AG (Volkswagen AG)
• Original Assignee: Audi AG (Volkswagen AG)
• Inventors: Achhammer, Siegfried
• Primary Examiner(s): Berhanu, Samuel
• Application Number:
  US14/003,617
• Publication Number:
  US 20130337294A1
• Time in Patent Office: 1,448 Days
• Field of Search: 324/433
• US Class Current: 1/1
• CPC Class Codes: B60L 2240/545 Temperature
• CPC Class Codes: B60L 2240/547 Voltage
• CPC Class Codes: B60L 2240/549 Current
• 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 50/64 Constructional details of batteries specially adapted for electric vehicles
• CPC Class Codes: B60L 58/10 for monitoring or controlling batteries
• CPC Class Codes: B60L 58/21 having the same nominal voltage
• CPC Class Codes: G01R 31/68 Testing of releasable connections, e.g. of terminals mounted on a printed circuit board
• CPC Class Codes: H01M 10/4207 for several batteries or cells simultaneously or sequentially
• CPC Class Codes: H01M 10/44 Methods for charging or discharging circuits for charging H02J7/00
• CPC Class Codes: H01M 10/448 End of discharge regulating measures
• CPC Class Codes: H01M 10/46 Accumulators structurally combined with charging apparatus circuits for charging H02J7/00
• CPC Class Codes: H01M 10/488 Cells or batteries combined with indicating means for external visualization of the condition, e.g. by change of colour or of light density
• CPC Class Codes: H01M 2200/103 Fuse
• CPC Class Codes: H01M 50/574 Devices or arrangements for the interruption of current
• CPC Class Codes: H01M 50/583 in response to current, e.g. fuses
• CPC Class Codes: H02J 7/00309 Overheat or overtemperature protection
• CPC Class Codes: H02J 7/0036 using connection detecting circuits H02J7/0034 takes precedence
• 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 battery for a vehicle has a plurality of battery cells forming a cell stack. During the operation of the battery, electrical energy can be drawn from the cell stack or supplied to the cell stack via at least one cable. At least one monitoring device, in particular an optocoupler, is used to monitor a resistance that is present on at least one detachable junction of the at least one cable to an additional component of the battery, wherein the monitoring device is connected in a parallel branch to the junction. By monitoring the resistance at the junctions, local overheating of the battery can be prevented.

Claims

1. A battery for a vehicle, comprising:

a plurality of battery cells forming a cell stack,

at least one cable connected to the cell stack, wherein electric energy can be drawn from the cell stack or supplied to the cell stack via the at least one cable during operation of the battery,

at least one monitoring device constructed as an optocoupler having an optical transmitter connected in parallel with the at least one junction for monitoring a resistance present on at least one detachable junction, at which the at least one cable is coupled with an additional component of the battery, wherein the monitoring device is connected in a parallel branch in parallel with the at least one junction, and

at least one resistance element connected upstream of the optical transmitter for setting a voltage value, wherein the optical transmitter emits light when the voltage value is exceeded, causing a controller to reduce or interrupt supplying electrical energy from or to the battery.

2. The battery of claim 1, wherein the optocoupler is a bidirectional optocoupler.

3. The battery of claim 1, wherein the at least one monitoring device is configured to monitor at least two serially-connected junctions.

4. The battery of claim 1, wherein the at least one monitoring device is coupled with a controller configured to reduce electrical energy supplied from the cell stack.

5. The battery of claim 4, wherein the electrical energy supplied from the cell stack is reduced to a value of zero.

6. The battery of claim 1, wherein the additional component is at least one contactor of the battery, and wherein the at least one monitoring device is connected in the parallel branch to

a terminal of the contactor on a side of cell stack or

a terminal of the contactor that is coupled to a high voltage terminal of the battery or

a load current path of the contactor encompassing two terminals of the contactor.

7. The battery of claim 1, wherein the additional component comprises a safety plug configured to interrupt an electrical connection within the cell stack.

8. The battery of claim 7, wherein the additional component comprises a fuse coupled with the safety plug.

9. A method for operating a battery for a vehicle, wherein the battery includes a plurality of battery cells forming a cell stack, comprising:

drawing electrical energy from the cell stack or supplying electrical energy to the cell stack via at least one cable,

monitoring a resistance present on at least one detachable junction with an optocoupler having an optical transmitter connected in parallel with the at least one detachable junction, at which the at least one cable is coupled with an additional component of the battery, with a monitoring device connected in a parallel branch that is connected in parallel with the at least one junction,

setting a voltage value with at least one resistance element connected upstream of the optical transmitter, wherein the optical transmitter emits light when the voltage value is exceeded, and

reducing or interrupting supplying electrical energy from or to the cell stack when the optical transmitter emits light.