SYSTEM AND METHOD FOR CONTROLLING A RECHARGEABLE BATTERY

• US 20070082258A1
• Filed: 08/09/2006
• Published: 04/12/2007
• Est. Priority Date: 08/09/2005
• Status: Active Grant

• Current Assignee: SAFT SA (Totalenergies Se)
• Original Assignee: SAFT SA (Totalenergies Se)
• Inventors: Chanson, Claude, Maloizel, Serge, MORIN, Christophe
• Granted Patent: US 7,745,039 B2
• Time in Patent Office: Days
• US Class Current: 429/61
• CPC Class Codes: B60L 58/15 Preventing overcharging
• CPC Class Codes: G01R 31/396 Acquisition or processing of data for testing or for monitoring individual cells or groups of cells within a battery
• CPC Class Codes: H02J 7/0013 acting upon several batteries simultaneously or sequentially H02J7/1423 takes precedence
• CPC Class Codes: H02J 7/0031 using battery or load disconnect circuits H02J9/002 takes precedence
• CPC Class Codes: H02J 7/0047 with monitoring or indicating devices or circuits
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries

Abstract

A control system for a rechargeable battery comprising at least two electrochemical generators electrically connected by a power line comprises a protection unit and at least two control units respectively connected to the terminals of each electrochemical generator. Each control unit is designed to measure at least one operating parameter pertaining to the said generator and to command the protection unit by transmission of carrier currents on the power line. The control system according to the invention dispenses with the master processor for commanding the battery protection units and reduces the connecting wires by dispensing with the measurement leads designed to transmit the measurements of the operating parameters of each generator to the master processor.

Claims

1. Control system for a rechargeable battery comprising at least two electrochemical generators electrically connected by a power line, the system comprising:

a protection unit;

at least two control units, respectively connected to the terminals of each electrochemical generator, each control unit being designed to measure at least one operating parameter pertaining to the said generator and to command the protection unit by transmission of carrier currents on the power line.

2. System according to claim 1, characterised in that the operating parameter measured by each control unit is chosen from the voltage at the terminals of the generator and/or the temperature in the generator and/or the current passing through the generator.

3. System according to claim 1, characterised in that each control unit comprises an electronic element designed to compare the parameter measured with a predetermined threshold and designed to command the transmission of a signal to the protection unit when the said parameter exceeds the predetermined threshold.

4. System according to claim 1, characterised in that each control unit comprises a frequency oscillator and a current generator in such a way as to produce high frequency current pulses transmitted on the power line.

5. System according to claim 1, characterised in that the protection unit (11) commands a switch (12) placed on the power line (3).

6. System according to claim 5, characterised in that the switch is designed to interrupt the charging and/or discharging of the battery.

7. System according to claim 1, characterised in that each control unit comprises a current sensor detecting the passage of current in the power line and a switch commanded by the said sensor, each unit being switched into standby mode when the current in the power line is below a predetermined value.

8. System according to claim 7, characterised in that, in standby mode, the control unit interrupts the measurement of the operating parameter of the generator.

9. System according to claim 1, characterised in that each control unit is designed to detect conditions in which the generator charging is complete, and to command diversion of the current locally.

10. System according to claim 1, characterised in that it does not comprise a master processor for all of the operating parameters measured at the terminals of each electrochemical generator.

11. Rechargeable battery comprising at least two electrochemical generators electrically connected by a power line, characterised in that it comprises a control system comprising:

a protection unit;

at least two control units, respectively connected to the terminals of each electrochemical generator, each control unit being designed to measure at least one operating parameter pertaining to the said generator and to command the protection unit by transmission of carrier currents on the power line.

12. Battery according to claim 11, characterised in that each electrochemical generator is chosen from a group comprising at least lithium ion generators, silver zinc generators, polymer generators, alkaline accumulators (Ni-Cad, Ni-MH) and lead technology batteries.

13. Method for the control of the voltage of a battery comprising at least two electrochemical generators electrically connected by a power line, the method comprising the following steps:

measurement of at least one operating parameter pertaining to each electrochemical generator, by a control unit connected to the terminals of the said generator;

detection of abnormal operating conditions by the said control unit;

transmission of a command signal to stop operation to a battery protection unit, comprising the steps of emission by the said control unit of carrier currents on the power line and reception of the said carrier currents by the protection unit;

interruption of the charging and/or discharging of the battery by the said protection unit.

14. Method according to claim 13, characterised in that the measurement step consists of measuring the voltage at the terminals of the generator and/or the temperature in the generator and/or the current passing through the generator.

15. Method according to claim 13, characterised in that the step of detection of abnormal operating conditions comprises a step of comparison of the operating parameter measured with a predetermined threshold.

16. Method according to claim 15, characterised in that the step of emission of a command to stop operation consists of generating high frequency current pulses and sending these pulses on the power line.

17. Method according to claim 13, characterised in that it also comprises one of the following steps:

measurement of the current passing through the power line by each control unit;

placing the control unit in standby when the current measured is below a predetermined value.