Voltage activated 2nd level safety circuit for permanent isolation

• US 8,649,140 B2
• Filed: 02/14/2012
• Issued: 02/11/2014
• Est. Priority Date: 03/04/2011
• Status: Active Grant

• Current Assignee: Electrochem Solutions, Inc.
• Original Assignee: Electrochem Solutions, Inc.
• Inventors: Peterson, Brian Robert, Carroll, Jon James, Sweetland, Todd, Decker, Gregory George
• Primary Examiner(s): Barnie, Rexford
• Assistant Examiner(s): MAI, TIEN HUNG
• Application Number:
  US13/396,068
• Publication Number:
  US 20120224289A1
• Time in Patent Office: 728 Days
• Field of Search: 361/78, 361/79
• US Class Current: 361/79
• CPC Class Codes: H02H 7/00 Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions
• CPC Class Codes: H02J 7/00308 Overvoltage protection
• CPC Class Codes: H02J 7/00309 Overheat or overtemperature protection
• CPC Class Codes: H02J 7/0031 using battery or load disconnect circuits H02J9/002 takes precedence

Abstract

A voltage activated 2^nd level safety circuit for permanent isolation having a current activated fuse useful for class III medical devices, military applications, and any other passive loads. The battery system has a fuse current limiter and the current activated fuse maintain the fuse closed when a power cell, having a current sufficient to blow the fuse expeditiously, directs its current to the load. The power cell continues to direct its current to the load until the system detects an unacceptable battery or circuit condition. Once that unacceptable condition exists and is detected, a fuse blowing circuitry allows the power cell'"'"'s current to expeditiously blow the current activated fuse. In response to the blown current activated fuse, the system'"'"'s isolation switch(es) open as well to establish a permanent isolated battery.

Claims

1. A battery pack, comprising:

a power cell;

a higher supply rail and a lower power supply rail electrically interconnecting the power cell and a load;

a first electronic switching device positioned, between the load and the power cell, on the lower power supply rail, wherein current passing through the lower power supply rail passes through the first electronic switching device'"'"'s source and drain when the first electronic switching device is in a conducting condition;

a current activated fuse having a current rated fuse below the power cell'"'"'s current and operatively coupled to (a) the power cell through an extension from one of the power supply rails, and (b) a fuse current limiter'"'"'s proximal end;

the fuse current limiter'"'"'s distal end operatively connects to the first electronic switching device'"'"'s gate, the fuse current limiter limits the amount of the power cell'"'"'s current that enters the current activated fuse and allows sufficient current from the power cell to pass to the first electronic switching device'"'"'s gate in a conducting condition;

an activation monitoring system that (a) monitors the battery pack for any over current condition, over voltage condition, thermally unacceptable condition, unacceptable battery or circuitry condition, or combinations thereof, and (b) transmits a closing current to a gate of an activation switch when the activation monitoring system detects the battery pack has an over current condition, an over voltage condition, a thermally unacceptable condition, an unacceptable battery or circuitry condition, or combinations thereof;

the activation switch operatively connects to (a) the current activated fuse or the fuse circuitry positioned between the current activated fuse and the fuse current limiter, and (b) the power cell'"'"'s most negative node or the lower power supply rail between the first electronic switching device and the power cell;

the activation switch closes upon receipt of the closing current and activates a fuse opening current circuit wherein the power cell transmits current through the current activated fuse so the current activated fuse opens;

in response to the current activated fuse opening, the first electronic switching device opens.

2. The battery pack of claim 1 wherein the current flows from the power cell to the load during a discharge control protocol.

3. The battery pack of claim 2 wherein the load is selected from the group consisting of an implantable medical device, a military device, a personal digital assistant, a cell phone, a laptop computer, and a power tool.

4. The battery pack of claim 1, further comprising an activation pull down resistor that operatively connects to (a) the activation circuitry between the activation switch and the power cell and (b) monitoring circuitry between the activation monitoring system and the activation switch.

5. The battery pack of claim 1, further comprising a second electronic switching device operatively connected to the power cell through the lower power supply rail and positioned between the load and the first electronic switching device.

6. The battery pack of claim 1 wherein the power cell is a rechargeable battery.

7. The battery pack of claim 1 wherein the first electronic switching device is a field effect transistor.

8. The battery pack of claim 5 wherein the second electronic switching device is a field effect transistor.

9. The battery pack of claim 1 wherein the activation switch is a field effect transistor.

10. The battery pack of claim 1 wherein the current activated fuse'"'"'s current rated fuse is less than 1000 mA.

11. The battery pack of claim 1 wherein the activation monitoring system monitors the battery pack for any over current condition, over voltage condition, thermally unacceptable condition, an unacceptable battery or circuitry condition, or combinations thereof on the higher power supply rail, the lower power supply rail, a negligible supply rail, or combinations thereof.

12. The battery pack of claim 1 further comprising an activation resistor positioned between (i) the activation switch and (ii) the power cell or the electrical circuitry between the first electronic switching device and the power cell.

13. The battery pack of claim 1 further comprising an activation signal current limiting resistor positioned between (i) the activation switch and (ii) the activation monitoring system.

14. The battery pack of claim 1 further comprising an activation pull down resistor between (i) the electrical circuitry connecting the activation switch and the activation monitoring system and (ii) the electrical circuitry connecting the activation switch and the power cell or the electrical circuitry between the first electronic switching device and the power cell.

15. The battery pack of claim 1 wherein the current activated fuse is operatively coupled to the power cell through an extension from the higher power supply rail.

16. A battery pack, comprising:

a rechargeable power cell;

a higher and lower power supply rail;

a first field effect transistor operatively coupled to the power cell on the lower power supply rail, wherein current passing through the power cell also passes through the first field effect transistor'"'"'s source and drain when the first field effect transistor is in a conducting condition;

a current activated fuse having a current rated fuse below the power cell'"'"'s current and operatively coupled to (a) the power cell through an extension from the higher power supply rail, and (b) a fuse current limiter'"'"'s proximal end;

the fuse current limiter'"'"'s distal end operatively connects to the first field effect transistor'"'"'s gate, the fuse current limiter limits the amount of the power cell'"'"'s current that enters the current activated fuse and allows sufficient current from the power cell to pass to the first field effect transistor'"'"'s gate in a conducting condition;

an activation monitoring system that (a) monitors the battery pack for any over current condition, over voltage condition, thermally unacceptable condition, unacceptable battery or circuitry conditions, or combinations thereof, and (b) transmits a closing current to an activation field effect transistor'"'"'s gate when the activation monitoring system detects the battery pack has an over current condition, an over voltage condition, a thermally unacceptable condition, an unacceptable battery or circuitry condition, or combinations thereof;

the activation field effect transistor operatively connects to (a) the current activated fuse or the fuse circuitry positioned between the current activated fuse and the fuse current limiter, and (b) the power cell'"'"'s most negative node or the electrical circuitry between the first field effect transistor and the power cell;

an activation resistor operatively connects to (i) the activation field effect transistor and (ii) the power cell or the lower power supply rail between the first field effect transistor and the power cell;

an activation signal current limiting resistor operatively connects to (i) the activation field effect transistor and (ii) the activation monitoring system;

an activation pull down resistor that operatively connects to (a) the activation circuitry between the activation switch and the power cell and (b) monitoring circuitry between the activation monitoring system and the activation switch;

the activation field effect transistor closes upon receipt of the closing circuit and opens a second electrical circuit wherein the power cell transmits current through the current activated fuse so the current activated fuse opens;

in response to the current activated fuse opening, the first field effect transistor opens.

17. The battery pack of claim 16 wherein the current flows from the power cell to a load during a discharge control protocol.

18. The battery pack of claim 17 wherein the load is selected from the group consisting of an implantable medical device, a military device, a personal digital assistant, a cell phone, a laptop computer, and a power tool.

19. The battery pack of claim 16, further comprising a second field effect transistor operatively connected to the power cell through the lower power supply rail and positioned between a load and the first field effect transistor.

20. The battery pack of claim 16 wherein the activation monitoring system monitors the battery pack for any over current condition, over voltage condition, thermally unacceptable condition, unacceptable battery or circuit condition, or combinations thereof on the higher power supply rail, the lower power supply rail, a negligible supply rail, or combinations thereof.

21. A battery pack, comprising:

a power cell;

a higher supply rail and a lower power supply rail electrically interconnecting the power cell and a load;

a first electronic switching device positioned, between the load and the power cell, on the higher power supply rail, wherein current passing through the higher power supply rail passes through the first electronic switching device'"'"'s source and drain when the first electronic switching device is in a conducting condition;

a current activated fuse having a current rated fuse below the power cell'"'"'s current and operatively coupled to (a) the power cell through an extension from the lower power supply rail, and (b) a fuse current limiter'"'"'s proximal end;

the fuse current limiter'"'"'s distal end operatively connects to the first electronic switching device'"'"'s gate, the fuse current limiter limits the amount of the power cell'"'"'s current that enters the current activated fuse and allows sufficient current from the power cell to pass to the first electronic switching device'"'"'s gate in a conducting condition;

an activation monitoring system that (a) monitors the battery pack for any over current condition, over voltage condition, thermally unacceptable condition, unacceptable battery or circuitry condition, or combinations thereof, and (b) transmits a closing current to a gate of an activation switch when the activation monitoring system detects the battery pack has an over current condition, an over voltage condition, a thermally unacceptable condition, an unacceptable battery or circuitry condition, or combinations thereof;

the activation switch operatively connects to (a) the current activated fuse or the fuse circuitry positioned between the current activated fuse and the fuse current limiter, and (b) the power cell'"'"'s most positive node or the upper power supply rail between the first electronic switching device and the power cell;

the activation switch closes upon receipt of the closing current and activates a fuse opening current circuit wherein the power cell transmits current through the current activated fuse so the current activated fuse opens;

in response to the current activated fuse opening, the first electronic switching device opens.

22. The battery pack of claim 21 wherein the current flows from the power cell to a load during a discharge control protocol.

23. The battery pack of claim 22 wherein the load is selected from the group consisting of an implantable medical device, a military device, a personal digital assistant, a cell phone, a laptop computer, and a power tool.

24. The battery pack of claim 21, further comprising a second electronic switching device operatively connected to the power cell through the higher power supply rail and positioned between the load and the first electronic switching device.

25. The battery pack of claim 21 wherein the activation monitoring system monitors the battery pack for any over current condition, over voltage condition, thermally unacceptable condition, unacceptable battery or circuit condition, or combinations thereof on the higher power supply rail, the lower power supply rail, a negligible supply rail, or combinations thereof.

26. A battery pack, comprising:

a power cell;

a higher supply rail and a lower power supply rail electrically interconnecting the power cell and a load;

a first electronic switching device positioned, between the load and the power cell, on the higher power supply rail, wherein current passing through the higher power supply rail passes through the first electronic switching device'"'"'s source and drain when the first electronic switching device is in a conducting condition;

a current activated fuse having a current rated fuse below the power cell'"'"'s current and operatively coupled to (a) the power cell through an extension from one of the power supply rails, and (b) a fuse current limiter'"'"'s proximal end;

the fuse current limiter'"'"'s distal end operatively connects to the first electronic switching device'"'"'s gate;

an activation monitoring system that (a) monitors the battery pack for any over current condition, over voltage condition, thermally unacceptable condition, unacceptable battery or circuitry condition, or combinations thereof, and (b) transmits a closing current to a gate of an activation switch when the activation monitoring system detects the battery pack has an over current condition, an over voltage condition, a thermally unacceptable condition, an unacceptable battery or circuitry condition, or combinations thereof;

the activation switch operatively connects to (a) the current activated fuse or the fuse circuitry positioned between the current activated fuse and the fuse current limiter, and (b) the power cell'"'"'s most negative node or the lower power supply rail;

the activation switch closes upon receipt of the closing current and activates a fuse opening current circuit wherein the power cell transmits current through the current activated fuse so the current activated fuse opens;

in response to the current activated fuse opening, the first electronic switching device opens.

27. The battery pack of claim 26 wherein the current flows from the power cell to a load during a discharge control protocol.

28. The battery pack of claim 27 wherein the load is selected from the group consisting of an implantable medical device, a military device, a personal digital assistant, a cell phone, a laptop computer, and a power tool.

29. The battery pack of claim 26, further comprising a second electronic switching device operatively connected to the power cell through the higher power supply rail and positioned between the load and the first electronic switching device.

30. The battery pack of claim 26 wherein the activation monitoring system monitors the battery pack for any over current condition, over voltage condition, thermally unacceptable condition, unacceptable battery or circuit condition, or combinations thereof on the higher power supply rail, the lower power supply rail, a negligible supply rail, or combinations thereof.

31. The battery pack of claim 26 wherein the first electronic switching device is a field effect transistor.

32. A battery pack, comprising:

a power cell;

a higher supply rail and a lower power supply rail electrically interconnecting the power cell and a load;

a first electronic switching device positioned, between the load and the power cell, on the higher power supply rail, wherein current passing through the higher power supply rail passes through the first electronic switching device'"'"'s source and drain when the first electronic switching device is in a conducting condition;

a current activated fuse having a current rated fuse below the power cell'"'"'s current and operatively coupled to (a) the power cell through an extension from the higher power supply rail, and (b) a fuse current limiter'"'"'s proximal end;

the fuse current limiter'"'"'s distal end operatively connects to the first electronic switching device'"'"'s gate;

an activation monitoring system that (a) monitors the battery pack for any over current condition, over voltage condition, thermally unacceptable condition, unacceptable battery or circuitry condition, or combinations thereof, and (b) transmits a closing current to a gate of an activation switch when the activation monitoring system detects the battery pack has an over current condition, an over voltage condition, a thermally unacceptable condition, an unacceptable battery or circuitry condition, or combinations thereof;

the activation switch operatively connects to (a) the current activated fuse or the fuse circuitry positioned between the current activated fuse and the fuse current limiter, and (b) the power cell'"'"'s most negative node or the lower power supply rail;

the activation switch closes upon receipt of the closing current and activates a fuse opening current circuit wherein the power cell transmits current through the current activated fuse so the current activated fuse opens;

in response to the current activated fuse opening, the first electronic switching device opens.

33. The battery pack of claim 32 wherein the current flows from the power cell to a load during a discharge control protocol.

34. The battery pack of claim 33 wherein the load is selected from the group consisting of an implantable medical device, a military device, a personal digital assistant, a cell phone, a laptop computer, and a power tool.

35. The battery pack of claim 32, further comprising a second electronic switching device operatively connected to the power cell through the higher power supply rail and positioned between the load and the first electronic switching device.

36. The battery pack of claim 32 wherein the activation monitoring system monitors the battery pack for any over current condition, over voltage condition, thermally unacceptable condition, unacceptable battery or circuit condition, or combinations thereof on the higher power supply rail, the lower power supply rail, a negligible supply rail, or combinations thereof.

37. The battery pack of claim 32 wherein the first electronic switching device is a field effect transistor.