Battery protection having controllable switching elements

• US 10,056,767 B2
• Filed: 06/23/2016
• Issued: 08/21/2018
• Est. Priority Date: 06/23/2016
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Inventors: Troberg, Mikael, Maki, Jani, Sermi, Tommi
• Primary Examiner(s): Tso, Edward
• Application Number:
  US15/191,102
• Publication Number:
  US 20170373514A1
• Time in Patent Office: 789 Days
• Field of Search: 320107, 320114, 320116, 320134, 320136
• CPC Class Codes: H02J 7/0014 Circuits for equalisation of charge between batteries
• CPC Class Codes: H02J 7/0031 using battery or load disconnect circuits H02J9/002 takes precedence
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries

Abstract

A device includes a rechargeable battery and a charging line, connected to a terminal of the rechargeable battery, charging the rechargeable battery. The charging line includes two switching elements electrically opening or closing the charging line, and a sense line, connected to a terminal of the rechargeable battery, sensing a battery voltage. The sense line includes two switching elements electrically opening or closing the sense line.

Claims

1. A device, comprising:

a rechargeable battery;

a charging line, connected to a first terminal of the rechargeable battery, charging the rechargeable battery, wherein the charging line comprises two switching elements electrically opening or closing the charging line; and

a sense line, connected to a second terminal of the rechargeable battery, sensing a battery voltage, wherein the sense line comprises two switching elements electrically opening or closing the sense line.

2. The device of claim 1, wherein the device further includes a battery protection control circuit configured to drive the switching elements.

3. The device of claim 2, wherein the battery protection control circuit and the switching elements for battery protection comprise an integrated circuit.

4. The device of claim 2 further comprising at least one additional battery protection control circuit, wherein:

the charging line comprising switching elements, comprises at least one additional switching element electrically opening or closing the charging line and configured to be driven by the at least one additional battery protection control circuit; and

the sense line comprising switching elements, comprises at least one additional switching element electrically opening or closing the sense line and configured to be driven by the at least one additional battery protection control circuit.

5. The device of claim 2, wherein the battery protection control circuit further comprises a sense element.

6. The device of claim 2, wherein the battery protection control circuit is configured to monitor a battery voltage.

7. The device of claim 6, wherein the battery protection control circuit is configured to turn off at least one switching element comprising the sense line and at least one switching element comprising the charging line, if the monitored battery voltage is above an upper threshold value or below a lower threshold value.

8. The device of claim 1, wherein the battery comprises multiple cells connected in parallel, series or a combination of parallel and series.

9. The device of claim 1, wherein the switching elements comprise field effect transistors, FETs.

10. The device of claim 1, further comprising a failsafe component between the sense line and the charging line of same polarity configured to electrically connect the sense line and the charging line if at least one of the switching elements comprising the sense line fails.

11. A battery protection circuit, comprising:

a battery protection control circuit;

two external charge terminals;

two external sense terminals;

two back to back switching elements electrically connected in between the charge terminals; and

two back to back switching elements electrically connected in between the sense terminals;

wherein the switching elements are controlled by the battery protection control circuit.

12. The circuit of claim 11, wherein the battery protection control circuit is configured to turn off at least one switching element between the two charge terminals and at least one switching element between the two sense terminals if battery voltage is above a pre-specified upper threshold value.

13. The circuit of claim 11, wherein the battery protection control circuit is configured turn off at least one switching element between the two charge terminals and at least one switching element between the two sense terminals if battery voltage is below a pre-specified lower threshold value.

14. The circuit of claim 11, wherein the battery protection control circuit and the switching elements are integrated in a single integrated package.

15. The circuit of claim 11, comprising a fail-safe component configured between charge and sense terminals of the same polarity, wherein the fail-safe component electrically connects the sense terminal to the corresponding charge terminal if switching elements are configured between the two sense terminals malfunction.

16. The circuit of claim 11, wherein the battery protection control circuit is configured to sense a voltage across a sense element, a switching element, or both the switching and sense elements.

17. The circuit of claim 11, wherein the switching elements comprise field effect transistors, FETs.

18. The circuit of claim 11, further comprising:

at least one additional battery protection control circuit;

at least two additional external charge terminals;

at least two additional external sense terminals;

two back to back switching elements electrically connected in between the additional charge terminals;

two back to back switching elements electrically connected in between the additional sense terminals;

wherein the switching elements are controlled by the at least one additional battery protection control circuit.

19. A method, performed by a processor, comprising

monitoring a battery voltage;

comparing the battery voltage to an upper threshold value;

comparing the battery voltage to a lower threshold value;

and if the battery voltage is higher than the upper threshold value or lower than the lower threshold value, electrically disconnecting charging lines and sense lines connected to the battery by switching off at least one switching element on at least one charging line and at least one switching element on at least one sense line.

20. The method of claim 19, further comprising:

monitoring the sense lines;

and if a sense line is detected to be in an electrically floating condition, connecting it to a charging line of the same polarity.