Patent US5898239A successfully refreshed from Google Patents.
US5898239A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Automatic electronic bypass power switch
Assignee: Lockheed Martin Corp
•
Filing: 1998-01-26
•
Granted: 1999-04-27
•
Expires: 2018-01-26
Abstract
Abstract In a multi-cell battery, an open-circuit failure of any one cell renders the entire battery unusable. An automatic electronic bypass switch is connected across each battery cell to provide a low-resistance conductive path around such battery cell should it fail. Contrary to conventional usage in which a fuse is employed to "clear" or "open" a short-circuit condition, the electronic switch of the present invention employs a fuse to activate a highly conductive path, which ideally would approach a short circuit, around an open-circuit condition. The electronic switch includes a field-effect transistor connected across the battery cell and a fuse to hold the field-effect transistor in the "off" condition. Diodes connected between the field-effect transistor and the fuse provide a current path for battery charging and/or discharging current to open the fuse if the battery cell fails open circuit, thereby allowing the field-effect transistor to turn to the "on" condition becoming a conductive path in parallel with the failed battery cell. An electronic switch is preferably connected across each cell of a multi-cell battery.
Inventors
- 👤 Elias Anthony Kawam
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 11:54
CPC Classifications
H; H01; H01M; H01M6/00; H01M6/50; G; G01; G01R; G01R31/00; G01R31/50; G01R31/52; H01M2200/00
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
131 words
A switch comprising: first and second conductors for connecting to a current-conducting workpiece; a controlled conduction semiconductor device having first and second electrodes and a controllable current conducting path therebetween, said first and second electrodes being respectively connected to said first and second conductors, said semiconductor device having a control electrode for controlling the conduction of current in said controllable current conducting path; a fusible conductive element coupled between the first and control electrodes of said semiconductor device for maintaining said semiconductor device non-conductive; a first diode connected between the second and control electrodes of said semiconductor device for conducting sufficient current to said fusible conductive element to cause said fusible conductive element to open circuit when the potential between said first and second conductors exceeds a first predetermined threshold level.
Claim 2
Dependent Claim
131 words
A switch comprising: first and second conductors for connecting to a current-conducting workpiece; a controlled conduction semiconductor device having first and second electrodes and a controllable current conducting path therebetween, said first and second electrodes being respectively connected to said first and second conductors, said semiconductor device having a control electrode for controlling the conduction of current in said controllable current conducting path; a fusible conductive element coupled between the first and control electrodes of said semiconductor device for maintaining said semiconductor device non-conductive; a first diode connected between the second and control electrodes of said semiconductor device for conducting sufficient current to said fusible conductive element to cause said fusible conductive element to open circuit when the potential between said first and second conductors exceeds a first predetermined threshold level.
Claim 3
Dependent Claim
42 words
The switch of claim 1 further comprising a conductive element coupling the control electrode of said semiconductor device to a source of potential to render the controllable conduction path of said semiconductor device conductive when said fusible conductive element is open circuit.
Claim 4
Dependent Claim
61 words
The switch of claim 1 further comprising a second diode connected between the second and control electrodes of said semiconductor device, and poled oppositely to said first diode, for conducting sufficient current to said fusible conductive element to cause said fusible conductive element to open circuit when the potential between said first and second terminals exceeds a second predetermined threshold level.
Claim 5
Dependent Claim
132 words
An electronic switch comprising: first and second terminals for connecting to a battery cell; a controlled conduction field-effect transistor having source and drain electrodes and a controllable current conducting path therebetween, said source and drain electrodes being respectively connected to said first and second terminals, said field-effect transistor having a gate electrode for controlling the conduction of current in said controllable current conducting path; a fusible conductive element coupled between the source and gate electrodes of said field-effect transistor for maintaining said field-effect transistor non-conductive; a first diode connected between the drain and gate electrodes of said field-effect transistor for conducting sufficient current to said fusible conductive element to cause said fusible conductive element to open circuit when the potential between said first and second terminals exceeds a first predetermined threshold level.
Claim 6
Dependent Claim
132 words
An electronic switch comprising: first and second terminals for connecting to a battery cell; a controlled conduction field-effect transistor having source and drain electrodes and a controllable current conducting path therebetween, said source and drain electrodes being respectively connected to said first and second terminals, said field-effect transistor having a gate electrode for controlling the conduction of current in said controllable current conducting path; a fusible conductive element coupled between the source and gate electrodes of said field-effect transistor for maintaining said field-effect transistor non-conductive; a first diode connected between the drain and gate electrodes of said field-effect transistor for conducting sufficient current to said fusible conductive element to cause said fusible conductive element to open circuit when the potential between said first and second terminals exceeds a first predetermined threshold level.
Claim 7
Dependent Claim
20 words
The electronic switch of claim 4 wherein said first diode includes a plurality of p-n junction diodes in series connection.
Claim 8
Dependent Claim
62 words
The electronic switch of claim 4 further comprising a second diode connected between the drain and gate electrodes of said field-effect transistor, and poled oppositely to said first diode, for conducting sufficient current to said fusible conductive element to cause said fusible conductive element to open circuit when the potential between said first and second terminals exceeds a second predetermined threshold level.
Claim 9
Dependent Claim
16 words
The electronic switch of claim 4 wherein said field-effect transistor includes a complementary heterojunction field-effect transistor.
Claim 10
Dependent Claim
44 words
The electronic switch of claim 4 further comprising a current conductive element coupling the control electrode of said semiconductor device to a source of potential to render the controllable conduction path of said field-effect transistor conductive when said fusible conductive element is open circuit.
Claim 11
Dependent Claim
29 words
The electronic switch of claim 8 wherein said current conductive element includes a resistive element for coupling the gate electrode of said field-effect transistor to said source of potential.
Claim 12
Dependent Claim
168 words
A battery comprising: a plurality of battery cells in series connection between first and second terminals; a plurality of electronic switches, each said electronic switch being connected across a respective one of said plurality of battery cells; wherein each said electronic switch comprises: a controlled conduction field-effect transistor having source and drain electrodes and a controllable current conducting path therebetween, said source and drain electrodes being respectively connected across said battery cell for providing a controllable current conducting path in parallel therewith, said field-effect transistor having a gate electrode for controlling the conduction of current in said controllable current conducting path; a fusible conductive element coupled between the source and gate electrodes of said field-effect transistor for maintaining said field-effect transistor non-conductive; and a first diode connected between the drain and gate electrodes of said field-effect transistor for conducting sufficient current to said fusible conductive element to cause said fusible conductive element to open circuit when the potential across said battery cell exceeds a first predetermined threshold level.
Claim 13
Dependent Claim
168 words
A battery comprising: a plurality of battery cells in series connection between first and second terminals; a plurality of electronic switches, each said electronic switch being connected across a respective one of said plurality of battery cells; wherein each said electronic switch comprises: a controlled conduction field-effect transistor having source and drain electrodes and a controllable current conducting path therebetween, said source and drain electrodes being respectively connected across said battery cell for providing a controllable current conducting path in parallel therewith, said field-effect transistor having a gate electrode for controlling the conduction of current in said controllable current conducting path; a fusible conductive element coupled between the source and gate electrodes of said field-effect transistor for maintaining said field-effect transistor non-conductive; and a first diode connected between the drain and gate electrodes of said field-effect transistor for conducting sufficient current to said fusible conductive element to cause said fusible conductive element to open circuit when the potential across said battery cell exceeds a first predetermined threshold level.
Claim 14
Dependent Claim
19 words
The battery of claim 10 wherein said first diode includes a plurality of p-n junction diodes in series connection.
Claim 15
Dependent Claim
15 words
The battery of claim 10 wherein said field-effect transistor includes a complementary heterojunction field-effect transistor.
Claim 16
Dependent Claim
41 words
The battery of claim 10 wherein the first predetermined threshold associated with one of said electronic switches exceeds the galvanic potential of the respective one of said plurality of battery cells to which said one of said electronic switches is connected.
Claim 17
Dependent Claim
65 words
The battery of claim 10 wherein said electronic switch further comprises a second diode connected between the drain and gate electrodes of said field-effect transistor, and poled oppositely to said first diode, for conducting sufficient current to said fusible conductive element to cause said fusible conductive element to open circuit when the potential between said first and second terminals exceeds a second predetermined threshold level.
Claim 18
Dependent Claim
23 words
The battery of claim 14 wherein said second predetermined threshold level is of opposite polarity to that of said first predetermined threshold level.
Claim 19
Dependent Claim
47 words
The battery of claim 10 wherein said electronic switch further comprises a current conductive element coupling the control electrode of said semiconductor device to a source of potential to render the controllable conduction path of said field-effect transistor conductive when said fusible conductive element is open circuit.
Claim 20
Dependent Claim
28 words
The battery of claim 16 wherein said current conductive element includes a resistive element for coupling the gate electrode of said field-effect transistor to said source of potential.
Claim 21
Dependent Claim
46 words
The battery of claim 17 wherein the battery cell to which said electronic switch is connected is electrically connected in said series connection of battery cells nearer to said first terminal than to said second terminal, and wherein said source of potential includes said second terminal.
References Cited (Backward Citations)
US3846679A
Cited
US4935315A
Cited
US5180641A
Cited
US5258244A
Cited
US5510598A
Cited
US5689209A
Cited
US5650240A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2002-04-26 | 2002-10-26 | 2003-04-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2006-04-26 | 2006-10-26 | 2007-04-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2010-04-26 | 2010-10-26 | 2011-04-27 | $7700.00 | Window Closed / Lapsed |