Non-sequential monitoring of battery cells in battery monitoring systems, and related components, systems, and methods

• US 9,612,287 B2
• Filed: 05/02/2012
• Issued: 04/04/2017
• Est. Priority Date: 05/02/2012
• Status: Active Grant

• Current Assignee: Ndsl, Inc.
• Original Assignee: Ndsl, Inc.
• Inventors: Brown, David, Belcher, Christopher James, Brown, Duncan Joseph, Chau, Dat Tan
• Primary Examiner(s): NGUYEN, NHA T
• Application Number:
  US13/461,862
• Publication Number:
  US 20130293995A1
• Time in Patent Office: 1,798 Days
• CPC Class Codes: G01R 31/386 using test-loads
• CPC Class Codes: G01R 31/389 Measuring internal impedance, internal conductance or related variables
• 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 7/0047 with monitoring or indicating devices or circuits
• CPC Class Codes: H02J 7/005 Detection of state of health [SOH]
• CPC Class Codes: H02J 9/04 in which the distribution system is disconnected from the normal source and connected to a standby source

Abstract

Non-sequential monitoring of battery cells in battery monitoring systems, and related components, systems, and methods are disclosed. In one embodiment, a battery monitoring system control unit is provided. The battery monitoring system control unit is configured to control battery monitoring devices. Each battery monitoring device is configured to be coupled to a subset of battery cells electrically connected in series in a sequential order to form a battery. The battery monitoring system control unit is further configured to instruct the battery monitoring devices to test an ohmic value of each battery cell of the battery cells of the battery in a non-sequential order. In this manner, heat generated in the battery monitoring devices from the testing may be more effectively dissipated, which can also allow for the battery monitoring devices to be employed in higher operating temperature environments.

Claims

1. A battery monitoring system control unit configured to control a plurality of battery monitoring devices, each battery monitoring device configured to be coupled to a subset of a plurality of battery cells electrically connected in series in a sequential order to form a battery,

the battery monitoring system control unit further configured to instruct the plurality of battery monitoring devices to test an ohmic value of each battery cell of the plurality of battery cells of the battery in a non-sequential order in which no adjacent battery cell among the plurality of battery cells is instructed to test an ohmic value in a sequential order,

wherein each subset of the plurality of battery cells includes M battery cells, wherein M is an integer greater than or equal to two (2),

wherein the total number of battery cells of the battery includes N battery cells, wherein N is an integer greater than or equal to four (4), and

wherein the order in which each battery cell I among the N battery cells is configured to be tested is (N/M)[(I−

1) mod M]+floor[(I−

1)/M]+1, wherein I is an integer between 1 and N inclusive.

2. The battery monitoring system control unit of claim 1 configured to instruct the plurality of battery monitoring devices to not test adjacent battery cells among the plurality of battery cells in a sequential order.

3. The battery monitoring system control unit of claim 1, wherein the battery comprises a plurality of battery cell substrings each comprising a unique set of battery cells among the plurality of battery cells,

each of the battery monitoring devices configured to test a unique battery cell substring among the plurality of battery cell substrings assigned to the respective battery monitoring device.

4. The battery monitoring system control unit of claim 3 configured to instruct each of the plurality of battery monitoring devices to test the unique set of battery cells in series of each battery cell substring assigned to the respective battery monitoring device.

5. The battery monitoring system control unit of claim 1 configured to repeat the instruction after all the battery cells have been tested.

6. The battery monitoring system control unit of claim 1, configured to:

instruct a battery monitoring device among the plurality of battery monitoring devices to test a first battery cell; and

instruct a battery monitoring device among the plurality of battery monitoring devices to test a next non-sequential battery cell.

7. The battery monitoring system control unit of claim 6, further configured to repeatedly instruct a battery monitoring device among the plurality of battery monitoring devices to test a next non-sequential battery cell until all battery cells of the battery have been tested.

8. The battery monitoring system control unit of claim 1 configured to instruct the plurality of battery monitoring devices to test each battery cell of the battery by:

coupling a current-inducing load to a battery cell substring comprising the battery cell to induce a current through the battery cell substring;

measuring a voltage of the battery cell;

determining the ohmic value of the battery cell based on the measured voltage; and

decoupling the current-inducing load from the battery cell substring to stop inducing the current through the battery cell substring.

9. A battery monitoring system, comprising:

a battery comprised of a plurality of battery cells electrically connected in series;

a plurality of battery monitoring devices each configured to be coupled to a subset of the plurality of battery cells; and

at least one battery monitoring system control unit configured to instruct the plurality of battery monitoring devices to test an ohmic value of each battery cell of the plurality of battery cells of the battery in a non-sequential order in which no adjacent battery cell among the plurality of battery cells is instructed to test an ohmic value in a sequential order,

wherein each subset of the plurality of battery cells includes M battery cells, wherein M is an integer greater than or equal to two (2),

wherein the total number of battery cells of the battery includes N battery cells, wherein N is an integer greater than or equal to four (4), and

wherein the order in which each battery cell I among the N battery cells is configured to be tested is (N/M)[(I−

1) mod M]+floor[(I−

1)/M]+1, wherein I is an integer between 1 and N inclusive.

10. The battery monitoring system of claim 9, wherein the at least one battery monitoring system control unit is configured to instruct the plurality of battery monitoring devices to not test adjacent battery cells among the plurality of battery cells in a sequential order.

11. The battery monitoring system of claim 9, wherein the battery comprises a plurality of battery cell substrings each comprising a unique set of battery cells among the plurality of battery cells,

each of the battery monitoring devices configured to test a unique battery cell substring among the plurality of battery cell substrings assigned to the respective battery monitoring device.

12. The battery monitoring system of claim 11, the at least one battery monitoring system control unit configured to instruct each of the plurality of battery monitoring devices to test the unique set of battery cells in series of each battery cell substring assigned to the respective battery monitoring device.

13. The battery monitoring system of claim 9, the at least one battery monitoring system control unit configured to repeat the instruction after all the battery cells have been tested.

14. The battery monitoring system of claim 9, the at least one battery monitoring system control unit configured to:

instruct a battery monitoring device among the plurality of battery monitoring devices to test a first battery cell; and

instruct a battery monitoring device among the plurality of battery monitoring devices to test a next non-sequential battery cell.

15. The battery monitoring system of claim 14, the at least one battery monitoring system control unit further configured to repeatedly instruct a battery monitoring device among the plurality of battery monitoring devices to test a next non-sequential battery cell until all battery cells of the battery have been tested.

16. The battery monitoring system of claim 9, the at least one battery monitoring system control unit configured to instruct the plurality of battery monitoring devices to test each battery cell by:

coupling a current-inducing load to a battery cell substring comprising the battery cell to induce a current through the battery cell substring;

measuring a voltage of the battery cell;

determining the ohmic value of the battery cell based on the measured voltage; and

decoupling the current-inducing load from the battery cell substring to stop inducing the current through the battery cell substring.

17. A method of a battery monitoring system control unit, comprising instructing a plurality of battery monitoring devices to test a plurality of battery cells electrically connected in series in a sequential order to form a battery by testing an ohmic value of each battery cell of the plurality of battery cells of the battery in a non-sequential order in which no adjacent battery cell among the plurality of battery cells is instructed to test an ohmic value in a sequential order,

wherein the plurality of battery cells comprise a plurality of subsets of battery cells,

wherein each of the plurality of subsets of battery cells includes M battery cells, wherein M is an integer greater than or equal to two (2),

wherein the total number of battery cells of the battery includes N battery cells, wherein N is an integer greater than or equal to four (4), and

wherein the instructing a plurality of battery monitoring devices comprises instructing the plurality of battery monitoring devices to test the plurality of battery cells in a non-sequential order, wherein the non-sequential order in which each battery cell I among the N battery cells is configured to be tested is (N/M)[(I−

1) mod M]+floor[(I−

1)/M]+1, wherein I is an integer between 1 and N inclusive.

18. The method of claim 17, comprising instructing the plurality of battery monitoring devices to not test adjacent battery cells among the plurality of battery cells in a sequential order.

19. The method of claim 17,

wherein the battery comprises a plurality of battery cell substrings each comprising a unique set of battery cells among the plurality of battery cells,

comprising instructing each battery monitoring device among the plurality of battery monitoring devices to test the unique set of battery cells in series of each battery cell substring assigned to the respective battery monitoring device.

20. The method of claim 17 further comprising repeating the instruction after all the battery cells have been tested.

21. The method of claim 17, comprising:

instructing a battery monitoring device among the plurality of battery monitoring devices to test a first battery cell; and

instructing a battery monitoring device among the plurality of battery monitoring devices to test a next non-sequential battery cell.

22. The method of claim 21, further comprising repeatedly instructing a battery monitoring device among the plurality of battery monitoring devices to test a next non-sequential battery cell until all battery cells of the battery have been tested.

23. The method of claim 17, wherein instructing the plurality of battery monitoring devices to test each battery cell comprises:

coupling a current-inducing load to a battery cell substring comprising the battery cell to induce a current through the battery cell substring;

measuring a voltage of the battery cell;

determining the ohmic value of the battery cell based on the measured voltage; and

decoupling the current-inducing load from the battery cell substring to stop inducing the current through the battery cell substring.

24. A non-transitory computer-readable medium having stored thereon computer-executable instructions to cause a processor to implement a method for controlling a plurality of battery monitoring devices to test an ohmic value of each battery cell of a battery, comprising:

instructing a plurality of battery monitoring devices to test a plurality of battery cells electrically connected in series in a sequential order to form a battery by testing an ohmic value of each battery cell of the plurality of battery cells of the battery in a non-sequential order in which no adjacent battery cell among the plurality of battery cells is instructed to test an ohmic value in a sequential order,

wherein the plurality of battery cells comprise a plurality of subsets of battery cells,

wherein each of the plurality of subsets of battery cells includes M battery cells, wherein M is an integer greater than or equal to two (2),

wherein the total number of battery cells of the battery includes N battery cells, wherein N is an integer greater than or equal to four (4), and

wherein the instructing a plurality of battery monitoring devices comprises instructing the plurality of battery monitoring devices to test the plurality of battery cells in a non-sequential order, wherein the non-sequential order in which each battery cell I among the N battery cells is configured to be tested is (N/M)[(I−

1) mod M]+floor[(I−

1)/M]+1, wherein I is an integer between 1 and N inclusive.

25. A battery monitoring system for testing ohmic values of battery cells of a battery, comprising:

a plurality of battery monitoring devices, each battery monitoring device configured to be coupled to a subset of a plurality of battery cells electrically connected in series in a sequential order to form a battery, wherein each battery monitoring device comprises a plurality of current leads configured to be coupled to the subset of battery cells assigned to the battery monitoring device to induce a current through the subset of battery cells;

wherein each battery monitoring device further comprises a plurality of voltage leads configured to be coupled to the subset of battery cells assigned to the battery monitoring device to measure a voltage of each battery cell of the subset;

a battery monitoring system control unit configured to control the plurality of battery monitoring devices, wherein each of the plurality of battery monitoring devices is configured to be coupled to a fiber optic loop for communications with the battery monitoring system control unit, wherein the battery monitoring system control unit is further configured to receive at least one pilot cell temperature measurement of the plurality of battery cells, wherein the battery monitoring system control unit is further configured to receive at least one battery current measurement of the battery, and

wherein the battery monitoring system control unit is further configured to instruct the plurality of battery monitoring devices to test an ohmic value of each battery cell of the plurality of battery cells of the battery in a non-sequential order in which no adjacent battery cell among the plurality of battery cells is instructed to test an ohmic value in a sequential order,

wherein each subset of a plurality of battery cells includes M battery cells, wherein M is an integer greater than or equal to two (2),

wherein the total number of battery cells of the battery includes N battery cells, wherein N is an integer greater than or equal to four (4), and

wherein the order in which each battery cell I among the N battery cells is configured to be tested is (N/M)[(I−

1) mod M]+floor[(I−

1)/M]+1, wherein I is an integer between 1 and N inclusive.

26. The battery monitoring system of claim 25, wherein the battery monitoring system control unit is further configured to:

instruct a battery monitoring device among the plurality of battery monitoring devices to test a first battery cell; and

instruct a battery monitoring device among the plurality of battery monitoring devices to test a next non-sequential battery cell.

27. The battery monitoring system of claim 26, wherein the battery monitoring system control unit is further configured to repeatedly instruct a battery monitoring device among the plurality of battery monitoring devices to test a next non-sequential battery cell until all battery cells of the battery have been tested.

28. The battery monitoring system of claim 25, wherein M equals four (4).

29. The battery monitoring system of claim 25 configured to instruct the plurality of battery monitoring devices to test each battery cell by:

coupling a current-inducing load to a battery cell substring comprising the battery cell to induce a current through the battery cell substring;

measuring a voltage of the battery cell;

determining the ohmic value of the battery cell based on the measured voltage; and

decoupling the current-inducing load from the battery cell substring to stop inducing the current through the battery cell substring.

30. The battery monitoring system of claim 25, further comprising a battery circuit breaker (BCB) configured to be coupled to the battery to protect the battery from overcurrents.

31. The battery monitoring system of claim 25, further comprising the battery.

32. A battery monitoring system control unit configured to control a plurality of battery monitoring devices, each battery monitoring device configured to be coupled to a subset of a plurality of battery cells electrically connected in series in a sequential order to form a battery,

the battery monitoring system control unit further configured to instruct the plurality of battery monitoring devices to test an ohmic value of each battery cell of the plurality of battery cells of the battery in a non-sequential order in which no adjacent battery cell among the plurality of battery cells is instructed to test an ohmic value in a sequential order,

wherein the plurality of battery cells comprise a plurality of subsets of battery cells,

wherein each of the plurality of subsets of battery cells includes M battery cells, wherein M is an integer greater than or equal to two (2),

wherein the total number of battery cells of the battery includes N battery cells, wherein N is an integer greater than or equal to four (4), and

wherein the battery monitoring control unit is further configured to test each of the N battery cells in a non-sequential order, and wherein the non-sequential order comprises:

a first battery cell from a first subset of the plurality of subsets of battery cells;

a first battery cell from a second subset of the plurality of subsets of battery cells;

wherein a second battery cell from the first subset of the plurality of subsets of battery cells is not tested before at least a first battery cell is tested from the second subset of the plurality of subsets of battery cells; and

wherein the non-sequential order comprises testing the first single battery cell from a first subset of the plurality of subsets of battery cells before testing the first battery cell from the second subset of the plurality of subsets.

33. A battery monitoring system control unit configured to control a plurality of battery monitoring devices, each battery monitoring device configured to be coupled to a subset of a plurality of battery cells electrically connected in series in a sequential order to form a battery,

the battery monitoring system control unit further configured to instruct the plurality of battery monitoring devices to test an ohmic value of each battery cell of the plurality of battery cells of the battery in a non-sequential order in which no adjacent battery cell among the plurality of battery cells is instructed to test an ohmic value in a sequential order,

wherein the plurality of battery cells comprise a plurality of subsets of battery cells,

wherein each of the plurality of subsets of battery cells includes M battery cells, wherein M is an integer greater than or equal to two (2),

wherein the total number of battery cells of the battery includes N battery cells, wherein N is an integer greater than or equal to four (4), and

wherein the battery monitoring control unit is further configured to test each of the N battery cells in a non-sequential order, and wherein the non-sequential order comprises:

a first battery cell from a first subset of the plurality of subsets of battery cells;

a first battery cell from a second subset of the plurality of subsets of battery cells;

wherein a second battery cell from the first subset of the plurality of subsets of battery cells is not tested before at least a first battery cell is tested from the second subset of the plurality of subsets of battery cells; and

wherein the battery monitoring control unit is further configured to test each of the N battery cells in a non-sequential order, wherein the non-sequential order comprises;

testing only a single battery cell from a first subset of the plurality of subsets of battery cells during a first time period;

testing only a single battery cell from a second subset of the plurality of subsets of battery cells during a second time period after the first time period; and

wherein a second battery cell from the first subset of the plurality of subsets of battery cells is not tested before at least a first battery cell is tested from the second subset of the plurality of subsets of battery cells.