Connectivity check between cells and wiring control electronics with only one switch

• US 10,236,695 B2
• Filed: 12/21/2016
• Issued: 03/19/2019
• Est. Priority Date: 12/22/2015
• Status: Active Grant

• Current Assignee: Vito NV
• Original Assignee: Vito NV
• Inventors: Weyen, Dominique
• Primary Examiner(s): Tso, Edward
• Assistant Examiner(s): Omar, Ahmed
• Application Number:
  US16/062,179
• Publication Number:
  US 20180375348A1
• Time in Patent Office: 818 Days
• Field of Search: 320116
• CPC Class Codes: G01R 31/36 Arrangements for testing, measuring or monitoring the electrical condition of accumulators or electric batteries, e.g. capacity or state of charge [SoC]
• CPC Class Codes: G01R 31/52 Testing for short-circuits, leakage current or ground faults
• CPC Class Codes: G01R 31/54 Testing for continuity
• CPC Class Codes: H02J 2310/18 The network being internal to a power source or plant
• CPC Class Codes: H02J 7/0019 using switched or multiplexed charge circuits
• CPC Class Codes: H02J 7/0024 Parallel/serial switching of connection of batteries to charge or load circuit
• CPC Class Codes: H02J 7/0036 using connection detecting circuits H02J7/0034 takes precedence
• CPC Class Codes: H02J 7/0063 with circuits adapted for supplying loads from the battery
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

A connectivity check for a rechargeable energy storage system including a string of rechargeable energy storage cell modules in series. Each cell module has an individual rechargeable energy storage cell or plurality of rechargeable energy storage cells, a switch for use in a connection check, a monitoring and control circuit adapted for measuring a cell module voltage, a single common connection between a terminal of a rechargeable energy storage cell and the monitoring and control circuit within each module. To perform the connectivity check the switch is opened in one module, a cell voltage is measured in the module to give a first measured value, the switch is closed. The cell voltage is measured again to provide a second measured value, and a determination is made if there is a difference between the first and second measured values which would indicate a bad connection.

Claims

1. A rechargeable energy storage system comprising a string of rechargeable energy storage cell modules in series, each cell module comprising:

connections for connecting to an individual rechargeable energy storage cell or plurality of rechargeable energy storage cells,

a controllable switch for use in a connection check,

a monitoring and control circuit adapted for measuring a cell module voltage, and

a filter circuit,

the rechargeable energy storage system further comprising;

a single common connection between a terminal of a rechargeable energy storage cell and the monitoring and control circuit within each module,

wherein the rechargeable energy storage system is adapted such that when all connections of the rechargeable energy storage system are intact, there is no change in voltage measurements through the monitoring and control circuit when the switch is open and when the switch is closed, whereas a deviation in the voltage measurements measured by the monitoring and control circuit when the switch is open and closed is an indication of a bad connection, wherein the switch is closed and the filter circuit is charged in case of a bad connection.

2. The rechargeable energy storage system according to claim 1, whereby all the switches of the cell modules are closed at the same time and that all the monitoring and control circuits of the cell modules measure the cell voltages with the switches open.

3. The rechargeable energy storage system according to claim 1, wherein the controllable switch is selected from:

the controllable switch being for control of when a module is to be balanced and

the controllable switch being for transfer of charge from the power source to the cell associated with the module where the switch is located.

4. The rechargeable energy storage system according to claim 1, wherein the single common connection is connected between a terminal of a rechargeable energy storage cell and two analog inputs of two monitoring and control circuits in different modules.

5. The rechargeable energy storage system according to claim 1, further comprising a filter connected between the switch and an analog input of a module.

6. The rechargeable energy storage system according to claim 1, wherein the bad connections are selected from a bad connection in the single common connection and a bad connection in a terminal of a cell.

7. The rechargeable energy storage system according to claim 1, further comprising a power source selected from:

the power source being connected to an input of each module and the switch, and

the power source being connected to an input of each module and the switch and a galvanic isolation being connected between the power source and the input of each module and its switch.

8. The rechargeable energy storage system according to claim 1, wherein the filter circuit is an inductor connected between the switch and an analog input to the module where the switch is located.

9. The rechargeable energy storage system according to claim 1, configured to assess whether a voltage deviation has a magnitude indicative of a bad connection.

10. The rechargeable energy storage system according to claim 1, wherein the closed time of the controllable switch is set.

11. A method of performing a connectivity check in a rechargeable energy storage system comprising a string of rechargeable energy storage cell modules in series, each cell module comprising:

connections to an individual rechargeable energy storage cell or plurality of rechargeable energy storage cells,

a switch for use in a connection check,

a monitoring and control circuit adapted for measuring a cell module voltage, and

a filter circuit,

the rechargeable energy storage system further comprising;

a single common connection between a terminal of a rechargeable energy storage cell and the monitoring and control circuit within each module, the method comprising for each module;

the switch is opened in one module,

measure a cell voltage in the module to give a first measured value

close the switch, wherein when the switch is closed the filter circuit is charged, if a bad connection is detected;

measure the cell voltage to provide a second measured value, and

determine if there is a voltage difference between the first and second measured values.

12. The method of claim 11, whereby all the switches of the cell modules are closed at the same time and that all the monitoring and control circuits of the cell modules measure the cell voltages with the switches open.

13. The method of claim 11, wherein a difference is indicative of a bad connection and an action is carried out, the action optionally being is a report of the defective cell number or activating an alarm.

14. The method of claim 11, wherein the bad connections are selected from a bad connection in the single common connection and a bad connection in a terminal of a cell.

15. The method of claim 11, further comprising operating the switches for control of when a module is to be balanced.

16. The method of claim 11, further comprising connecting the single common connection between a terminal of a rechargeable energy storage cell and two analog inputs of two monitoring and control circuits in different modules.

17. The method of claim 11, further comprising connecting a power source is selected from:

connecting the power source to an input of each module and its switch and

connecting the power source to an input of each module and its switch with a galvanic isolation between the power source and the input of each module and its switch.

18. The method according to claim 17, wherein the switch is for transfer of charge from the power source to the cell associated with the module where the switch is located.

19. The method of claim 11, further comprising connecting a filter selected from

connecting a filter between the switch and an analog input of a module, and

connecting a filter between the switch and an analog input of a module, the filter being an inductor connected between the switch and an analog input to the module where the switch is located.

20. A computer program product comprising software code segments, which when implemented on a processing engine, executes method of claim 11, wherein the computer program product is optionally stored on a non-volatile signal storage device.